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Original Research ARTICLE
Winged Pea Aphids Can Modify Phototaxis in Different Development Stages to Assist Their Host Distribution
- 1State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, China
- 2Key Laboratory of Integrated Pest Management on the Loess Plateau of Ministry of Agriculture, Northwest A&F University, Yangling, China
The pea aphid, Acyrthosiphon pisum (Harris) (Hemiptera: Aphididae), shows wing polyphenism (winged and wingless morphs) in its life cycle. The winged morph is adapted for dispersal; its two developmental adult stages (for dispersal and reproduction) are based on its breeding periods. The two morphs show different phototactic behavior and the winged can change its preference to light according to the developmental stages. To determine the mechanism and ecological functions of phototaxis for A. pisum, we first investigated the phototaxis of the two aphid morphs at different stages and analyzed the phototactic response to lights of different wavelengths; the correlation between alate fecundity and their phototactic behaviors were then studied. Finally, we focused on the possible functions of phototaxis in aphid host location and distribution in combination with gravitaxis behaviors. Negative phototaxis was found for breeding winged adults but all the other stages of both winged and wingless morphs showed positive phototaxis. The reactions of the aphids to different wavelengths were also different. Nymph production in winged adults showed negative correlation to phototaxis. The dopamine pathway was possibly involved in these behavior modifications. We speculated that winged adults can use light for dispersal in the early dispersal stage and for position holding in the breeding stage. Based on our results, we assume that light signals are important for aphid dispersal and distribution, and are also essential for the pea aphids to cope with environmental changes.
The pea aphid Acyrthosiphon pisum (Harris), exhibits wing phenotypes at various stages of its life cycle (Braendle et al., 2006). Normally, winged morph is adapted for dispersal and wingless morph for reproduction. The winged and wingless phenotypes in aphids differ in morphology, physiology, and behavior. The winged morph exhibits an elaborate sensory system for flight and host plant location, such as more fully developed compound eyes, ocelli, and longer antennae with more rhinaria as compared with the wingless morph. The wingless morph lacks wings and the wing musculature for dispersal, but it has a faster development time and a larger body size for production than the winged morph (Braendle et al., 2006; van Emden and Harrington, 2007; Brisson, 2010). Density (tactile stimulation) and nutrition (host plant quality) are considered to be the key environmental cues affecting the transformation from winged to wingless morphs. This represents an adaptation of the pea aphid to the environment (Johnson, 1965; Lees, 1967; Sutherland, 1969; Sutherland and Mittler, 1971; Wratten, 1977).
Taxis is the movement of an organism in response to different stimuli including physical, chemical, and biological ones; movements of an organism toward or away from a stimulus, are defined as positive or negative taxis, respectively. Many types of taxis have been identified, such as chemotaxis (by chemicals), electrotaxis (by electric current), gravitaxis (by gravity), hydrotaxis (by moisture), phototaxis (by light), and thermotaxis (by temperature) (Hader, 1987; Mori and Ohshima, 1995; Alon et al., 1999; Pringault and Garcia-Pichel, 2004; Rezai et al., 2010). Phototaxis is a locomotory movement toward or away from a light stimulus for an organism. Many organisms show phototaxis from prokaryotes to eukaryotes including plants and animals (Bulkowski and Meade, 1983; Armitage and Hellingwerf, 2003; Chen et al., 2012). Insects also display such behaviors; for instance, moths, wasps, and whiteflies (Summers, 1997; Castrejon and Rojas, 2010; Chen et al., 2012; Yang et al., 2012). Phototaxis has been widely used in pest control; for instance, in the invention of light traps and yellow card traps, which are based on insect phototaxis to ultraviolet and yellow light (Bowden, 1982). On the other hand, the phototaxis of an organism may change during its life time. It has been recorded that some insect species can change their phototaxis or geotaxis in certain situations, such as developmental stages and starvation (De Ruiter and van der Horn, 1957; Barrett and Chiang, 1967; Ben-Shahar et al., 2003; Gong et al., 2010). Phototactic changes in particular situations may also be occurring in some other animals, such as fish, nudibranch, and stomatopod species (Dingle, 1969; Bulkowski and Meade, 1983; Miller and Hadfield, 1986).
Phototactic behaviors are stimulated by light, and light in different wavelengths may affect phototaxis in insects in different ways. Many insects prefer blue light or ultraviolet, and others can be attracted by green or yellow light. Insects can react to more than one wavelength bands (Coombe, 1981; Yang et al., 2003; Mazza et al., 2010; Yamaguchi et al., 2010). Light with different wavelengths can stimulate visual organs and lead to different reactions in insects (Yokoyama, 2000; Briscoe and Chittka, 2001). Studies show sensors in both ocelli and compound eyes could be functional in phototactic behaviors (Garrey, 1918; Gilbert, 1994; Lazzari et al., 1998). The study of one aphid species Megoura viciae labeled some photoperiodic photoreceptors including red-light sensitive photoreceptor-specific proteins (CERN-956) and long-wavelength sensitively photoreceptor-specific proteins (COS-1) in ventral neuropile of protocerebrum and eyes (Gao et al., 1999).
As a complex behavior in insects, phototaxis is controlled by the insect neural system. Previous studies in insects and other animal species showed neurotransmitters (dopamine, serotonin, and so on) played specific roles in phototactic behavior. Dopamine (3, 4-dihydroxyphenethylamine, DA) is an important neurotransmitter and hormone of the catecholamine and phenethylamine families (Joh and Hwang, 1987). Dopamine has been well studied in human and other mammals. Studies reveal that dopamine plays important roles in motor function, reward, learning, aggression, addiction, memory, and some other behaviors in invertebrates, as well as those in vertebrates (Coleman and Neckameyer, 2004; Rauschenbach et al., 2012; Martin and Krantz, 2014). Dopamine is also a key chemical in cuticle maturation (sclerotization and melanization) (Gallot et al., 2010). Researches in Drosophila showed that dopamine functioned in phototaxis, while dopamine-deficient flies were also defective in positive phototaxis (Neckameyer et al., 2001; Riemensperger et al., 2011). Serotonin played a key role in phototactic behavior in the honeybee, Apis mellifera (Thamm et al., 2010). There is also some evidence in other animals: dopamine could prolong while serotonin could repress positive phototaxis in Bugula neritina (Pires and Woollacott, 1997), and serotonin has been reported as negatively modifying phototaxis in a species of crab Carcinus maenas (McPhee and Wilkens, 1989).
An understanding of phototaxis would be helpful in studies of aphid dispersal and distribution. Previous studies in many aphid species showed that aphids display phototactic behaviors and normally show a positive preference (Kennedy et al., 1961; Kennedy and Booth, 1963; Hajong and Varman, 2002). During our many years of pea aphid rearing, we found that different aphid morphs did have different phototactic behaviors. The understanding of this changeable phototactic behavior and its underlying mechanism in A. pisum reflects the adaptation of A. pisum to its ecological conditions.
Gravitaxis response might affect aphid's movement patterns and response for upward climbing on host plants. Only few gravitaxis related studies could be found in Drosophila melanogaster (Toma et al., 2002; Armstrong et al., 2006) and there is no gravitaxis receptor researches about aphid to our data. Some studies mentioned aphids exhibited negative gravitaxis (Brunissen et al., 2010; Le Roux et al., 2010) or positive and negative gravitaxis (Pettersson et al., 2007) without further detailed studies. The gravitactic behavior of the pea aphid was then determined.
To determine the underling mechanisms of phototactic behaviors, we first recorded the phototactic response of two morphs of the pea aphid in different nymphal instars to white light. Based on the different phototactic results in winged adults, we analyzed the relationship between phototactic response and fecundity; and then we focused on the phototactic behaviors of selected aphids to different wavelengths of light. We also designed experiments to analyze the possible connections between neurotransmitters (dopamine, octopamine, and serotonin) and aphid phototactic behavior changes. Finally, combining with the results for gravitaxis of the pea aphid, we designed an experiment to study the possible functions of phototaxis in pea aphid host-distribution.
Materials and Methods
Aphids and Plants
A red morph of pea aphid was collected from Lanzhou, Gansu Province, China, and reared on broad bean (Vicia faba L., var. "Jinnong") under a long-day condition (16L: 8D; 20 ± 1°C) for more than 30 generations at the Key Laboratory of Applied Entomology, Northwest A&F University, Yangling, Shaanxi, China. All wingless aphids were reared at a low density (< 30 aphids per 4-week-old plant) for more than three generations before they were used. A high density (30 aphids per 2-weeks old plant seedling) was used to stimulate wing formation. Selected winged aphids were reared at a low density (< 30 aphids per 4-weeks old seedling) before they were used in all subsequent experiments.
Phototaxis Behaviors in Different Instars of Winged and Wingless Pea Aphids
Phototactic preference of the aphids were determined by comparing the numbers of aphids that moved to a lighted area or remained in a dark area as shown in Figure 5A. The arena was made of a transparent plastic petri dish (90 mm in diameter). A lighted area was formed by placing a piece of white filter paper (45 mm in diameter) in the bottom for light reflection; a cold light (KL 1500 LCD, Zeiss, German, set color temperature at 6500 K, 2000 lx) was used as a light source. The lens was focused on the filter paper forming a sharp-edged circle (45 mm in diameter, the same size as the filter paper). The remaining area remained in the dark. The lighted area was one fourth and the dark area was three fourth of the arena. We tested the phototactic preference of wingless nymphs (first and second instars), winged nymphs (third and fourth instars), wingless adults (1-day old), and winged adults (newly emerged and 8-days old, Figure 1D). All aphids were starved for 6 h before they were used. The experiments were undertaken in a dark room at 10:00 a.m., and each treatment lasted for 30 min. During the experiment, 50 starved aphids were placed in each arena, and numbers of aphids moved to the lighted area and those remained in the dark area were counted. Each experiment was repeated 15 times.
Figure 1. Phototactic response in different stages and wing forms of Acyrthosiphon pisum. The phototaxis results in different stages of A. pisum (A). The fecundity and phototaxis correlations in winged adults during their development (B), and the phototaxis changing in starvation of winged adults in breeding period (C); winged adult in pre-breeding (left) and breeding (right) period (D). Phototaxis in wingless adults 1-day and 8 d winged adults under light with different wavelengths, in red (>600 nm, E), green (400–600 nm, F) and blue (350–500 nm, G). Data were based on aphids' density (number/unit). The light area has 1 unit while dark area has 3 units. * and ** indicate significant different at P < 0.05 and P < 0.01, respectively (Student's t-test). The different letters next to the bars indicate significant differences at P < 0.05 (Duncan test).
Correlation between Nymphs Production and Phototaxis in the Winged Adults
Newly emerged winged pea aphid adults were reared at a low density (< 30 individuals per seedling). The nymphs produced were individually counted every day for 8 days. Phototaxis was also determined for 8 days as described above. The correlation of nymphs produced and phototaxis was analyzed for each treatment. Each experiment was repeated 15 times.
Phototaxis of Starved Winged Adults
Eight-days old winged adults in their reproduction period were starved for 6, 8, 10, 12, 14, 16, or 18 h before they were used in the phototaxis experiments as described above. We selected wingless adults (3 days old), and winged adults (1-day old and 8-days old) in the experiments. Each treatment was repeated 15 times.
Phototactic Behaviors to Different Light Wavelengths
In this experiment, we determined the effects of three light wavelengths on phototaxis of different morphs of the pea aphid. The three wavelengths (red: >600 nm; green: 400–600 nm; blue: 350–500 nm) were obtained by using band filters on the lenses of a cold light source (KL 1500 LCD) (Figure 5B). Phototaxis of the aphids was determined as described above. Each treatment was repeated 15 times.
Transcription in DDC, TβH, and TPH
Detection of rate-limiting enzyme transcription levels in neurotransmitter production was used for neurotransmitter analysis. Considering the high L-DOPA contents in the host plants V. faba (Ingle, 2003; Zhang et al., 2016), we picked DDC (DOPA Decarboxylase) downstream for dopamine analysis; TβH (Tyramine β-Hydroxylase, converted L-tyramine to octopamine) was selected for octopamine and TPH (Tryptophan Hydroxylase, and converted L-tryptophan to 5-Hydroxy-L-tryptophan) for serotonin (Figure S2).
To analyze expression differences in DDC, TβH, and TPH, wingless and winged adults in the first and eighth day were snap-frozen and dissected between the T1 and T2 segments (Figure 2F). The head and T1 segment (to avoid affecting embryos in the abdomen) were used for transcription tests, and 15 individuals were prepared for one repetition. There experiments were repeated three times. Aphid samples were frozen using liquid nitrogen immediately after collection. RNA was extracted with RNAiso Plus (Takara, Japan), and cDNA was synthesized using a PrimeScript™ RT reagent kit with gDNA Eraser (Takara, Japan). Quantitative real-time PCR (qRT-PCR) was performed with SYBR® Premix Ex Taq™ II (Takara, Japan) in an IQ-5 system (Bio-Rad, Berkeley, California, USA). The primers were designed by Primer-BLAST of NCBI online (http://www.ncbi.nlm.nih.gov/tools/primer-blast/index.cgi?LINK_LOC=BlastHome) (Table S1).
Figure 2. Relative expression analysis of key enzymes of neurotransmitters in selected Acyrthosiphon pisum and phototactic tests after injection experiments in A. pisum. Relative expression levels of DDC (DOPA Decarboxylase, A), TβH (Tyramine β-Hydroxylase, B) and TPH (Tryptophan Hydroxylase, C) in three selected Acyrthosiphon pisum (1-day and 8-day winged adults and wingless adults) and their phototaxis tests (E); relative expression levels of DDC between injected and uninjected A. pisum (D). Dissection (dotted line) and injection (dark spots) position are showing in (F). Each value represents the mean ± SEM from independent determinations. ** in both D and E indicate that the means are significantly different at P < 0.01 (Student's t-test), and different letters on top of the bars indicate significant differences at P < 0.05 (Duncan test).
Dopamine Antagonist Treatments
To further analyze the dopamine functions in phototactic behavior, dopamine receptor antagonist was injected to modify the dopamine level in the pea aphids. Based on the aphid's locomotion and pretests, 1-day old winged adults were used for the experiments. SCH23390 (R(+)-7-chloro-8-hydroxy-3-methyl-1-phenyl-2, 3, 4, 5-tetrahydro-1H-3-benzazepine hydrochloride, CAS 125941-87-9, sigma, D1 receptor antagonist) (Peczely et al., 2014) and Sulpiride ((−)-5-(aminosulfonyl)-N-[(1-ethyl-2-pyrrodinyl)methyl]-2-methoxy-benzamide, CAS 15676-16-1, sigma, D1 and D2 receptor antagonist) (Hauber and Lutz, 1999) were used in the experiments. A high dose (2.5 mM) of antagonist was used for injection as described by Vergoz et al. (2007).
The methods of injection of dopamine antagonist solution were described by Barron et al. (2007) and Scheiner et al. (2002). A glass needle (P-97 Micropipette Puller, Sutter, CA, USA; a pulling program: Pull = 100, VEL = 100, and Time = 100) attached to the Nanoject II™ Auto-Nanoliter Injector (Drummond Scientific Company, USA) was used in the injection. Dopamine antagonist solution was injected into the thorax (T3 segment) of the aphids, and thoracic injections were made through the fissure at the base of their hind legs (Figure 2F); 200 nl solution was injected per aphid; ddH2O in the same dose (200 nl) was used as a control. The aphids were then moved to V. faba after treatment. All samples were used for phototaxis tests after 8 h host rearing followed by 6 h starvation. Phototaxis experimental protocol are described above. Injected and control winged aphids (1-day) for DDC were used for transcription analysis. The transcription analysis protocol was followed as described above.
Gravitaxis Analysis
Bottom Release
Fifty aphids were put on the bottom dish of the device and sealed by aluminum foil. The cylinders were divided into five parts by height (A, B, C, D, and E). The experiments lasted for 3 h, and the aluminum foil was then removed, and number of aphids in each position was counted.
Top Release
Fifty selected aphids were put into the container. The dish with aphids was covered for 1 h; the device was sealed with aluminum foil immediately after aphid release. The experiment lasted for 3 h, and the aluminum foil was then removed, and number of aphids in each position was counted. The gravitaxis of the pea aphids was determined as shown in Figure 5C.
The Effect of Light on Aphid Spatial Distribution on Host Plants
This experiment was conducted to determine possible effects of lighting direction on phototactic behavior and spatial distribution of pea aphids on host plants (Figure 5D). Four-week-old V. faba were used as the host plants. A piece of filter paper made into a cone was used to hold aphids. A cold light source (KL 1500 LCD, Zeiss, German, set color temperature at 6500 K, 8000 lx) was placed on top or bottom of the plant depending on experiment design. A no-light treatment was used as a control. Fifty aphids were used each time. The leaves on the plant were marked from top to bottom as A, B, C, and D (Figure 5D), and number of aphids on each leaf was counted 3 h later. The experiment was conducted in a dark room, and each experiment was repeated 10 times.
Statistical Analysis
All experimental data generated were collected and subjected to statistical analysis using Student's t-test, and one-way ANOVA; means were separated using Duncan test; Kolmogorov–Smirnov test were used for distribution analysis and Pearson correlation test were used for correlation analysis (SPSS version 22; SPSS Inc., Chicago, IL, USA).
Phototactic Behavior Analysis in Different Instars of Winged and Wingless Pea Aphid
The phototaxis responses in the winged adults showed significant difference. Based on the counts of aphids in the dark and light areas, the aphids were strongly attracted to the light except to the 8-days old winged adults which showed negative phototaxis (t = −3.108, df = 28, P = 0.006; Figure 1A). The 1-day-old winged adult showed the strongest taxis to the light while the first and second instars showed weaker light preference than other positive-phototactic aphids (F = 51.682, df = 8, 126, P < 0.0001, Figure 1A).
Correlation Analysis between Nymphs Production and Phototaxis in Winged Adult Pea Aphid
The newly emerged winged adults in the first 2 days after emergence showed significant positive phototaxis (1 d, t = −7.502, df = 17, P < 0.0001; 2 d, t = −6.014, df = 17, P < 0.0001, Figure 1B); and showed slight negative phototaxis in the following 4 days (3 d, t = −0.301, df = 17, P = 0.767; 4 d, t = 2.720, df = 17, P = 0.015, 5 d, t = 1.542, df = 28, P = 0.141; 6 d, t = 1.003, df = 17, P = 0.330, Figure 1B); obvious negative phototaxis were observed at the seventh and eighth days (7 d, t = 2.851, df = 17, P = 0.011; 8 d, t = 4.698, df = 17, P < 0.0001, Figure 1B). There was an increase in nymph production during this process (F = 73.579, df = 7, 232, P < 0.0001, Figure 1B), which was negatively correlated with phototaxis (Pearson r = −0.724, P = 0.042).
Changes in Phototaxis of Winged Adults (Breeding Period) in Starvation
Eight-days old winged adults could develop positive phototaxis when staved. This happened after 12 h of starvation (6 h: t = 4.698, df = 17, P < 0.0001; 8 h: t = 2.337, df = 17, P = 0.032: 10 h: t = −0.025, df = 17, P = 0.981: Figure 1C), which could change into significant positive phototaxis (12 h: t = −3.171, df = 17, P = 0.006; 14 h: t = −3.924, df = 17, P = 0.001; 16 h: t = −6.747, df = 18, P < 0.0001; 18 h: t = −8.098, df = 17, P < 0.0001: Figure 1C).
Phototactic Behavior Analysis in Response to Different Light Wavelengths
The aphids showed different phototactic reactions to different light wavelengths. In the red light treatment (>600 nm), wingless adults showed significant positive phototaxis (t = −2.676, df = 17, P = 0.016), and 1-day old winged adults showed stronger preference for red light (t = −9.816, df = 17, P < 0.0001). Eight-days old winged adults showed no reaction to red light (t = −0.253, df = 17, P = 0.803; Figure 1E). In the green light treatment (400–600 nm), wingless adults also showed significant positive phototaxis (t = −6.718, df = 17, P < 0.0001); 1-day-old winged adults showed no reaction to green light (t = −0.695, df = 17, P = 0.496); while 8-days old winged adults showed significant negative phototaxis (t = 2.505, df = 17, P = 0.023; Figure 1F). In the blue light (350–500 nm) experiment, both wingless adults and 1-day old winged adults showed significant positive phototaxis (wingless adults: t = −20.270, df = 17, P < 0.0001; winged adults: t = −18.947, df = 17, P < 0.0001), and for 8-days old winged adults the difference was not significant (t = 1.559, df = 17, P = 0.137; Figure 1G).
Dopamine, Octopamine, and Serotonin Analysis
By analyzing rate-limiting enzyme transcription levels of dopamine (DDC), we found that 8-day winged adults showed more significant down-regulation than the others (F = 7.635, df = 2, 6, P = 0.022; Figure 2A). In octopamine (TβH) analysis, wingless adults showed the lowest expression level among all aphid stages and 1-day-old winged adults showed the highest (F = 8.385, df = 2, 12, P = 0.005; Figure 2B). The serotonin analysis (TPH) for wingless adults showed more significant down-regulation than for another two aphids (F = 8.385, df = 2, 9, P = 0.010; Figure 2C).
Dopamine Antagonists Treatment
After 1-day-old aphid adults were injected, their phototactic behaviors also changed. All injected aphids showed no response to light (SCH23390, t = −1.539, df = 28, P = 0.135; sulpiride, t = −0.319, df = 28, P = 0.752; H2O, t = −1.296, df = 28, P = 0.206; Figure 2E).
By analyzing DDC transcription level between injected aphids and the control, we found that DDC showed significant down-regulation in injected individuals (t = −5.334, df = 4, P < 0.006; Figure 2D).
Gravitaxis Analysis
Gravitaxis analysis indicated that no obvious gravitaxis in all aphids tested. In the bottom release experiment, all aphids were still at the bottom 3 h after the experiment (1-day-old winged adults, F = 357.987, df = 4, 70, P < 0.0001; 8-days-old winged adults, F = 105.846, df = 4, 70, P < 0.0001; wingless adults, F = 213.327, df = 4, 70, P < 0.0001; Figures 3A,C,E). In the top release experiment, most aphids were still at the top, although some moved downward. One-day-old winged adults showed a wider spread (1-day-old winged adults: F = 19.088, df = 4, 70, P < 0.0001; 8-days-old winged adults: F = 46.870, df = 4, 70, P < 0.0001; wingless adults: F = 19.649, df = 4, 70, P < 0.0001; Figures 3B,D,F), which represented some degree of positive gravitaxis.
Figure 3. Gravitaxis analysis of selected Acyrthosiphon pisum. One-day winged adults in bottom-releasing (A) and top-releasing (B); 8-day winged adults in bottom-releasing (C) and top-releasing (D), wingless adults in bottom-releasing (E) and top-releasing (F). Different letters next to the bars are significantly different (P < 0.05, Duncan test).
Light Attraction Analysis in Pea Aphid Host Spatial Distribution
The spatial distribution of 1-day old winged adults was affected by lighting direction, and more aphids aggregated at the lighting source (A: F = 8.339, df = 2, 27, P = 0.001; B: F = 57.709, df = 2, 27, P < 0.0001; C: F = 3.065, df = 2, 27, P = 0.063; D: F = 42.685, df = 2, 27, P < 0.0001). More than one third of the aphids (bottom lighting: 52.67%; top lighting: 37.67%; no lighting: 56.33%) were not on the host after the experiments, and the bottom-lighting attracted more aphids than the top-lighting and no-lighting treatments (F = 49.242, df = 2, 27, P < 0.0001; Figure 4A).
Figure 4. Distributions of Acyrthosiphon pisum under different lights. Distributions of 1-day old winged adults (A), 8-days old winged adults (B), and wingless adults (C) as indicated by the aphids numbers in each part under different lights. Aphid lost in the three selected aphids were shown in (D). Different letters next to the bars are significantly different (P < 0.05, Duncan test).
For 8-day winged adults, the distribution was also affected by lighting direction (Figure S1A), and only position A (marked on Figure 5D) had a significant increase in aphids numbers in the bottom-lighting treatment (A: F = 37.175, df = 2, 27, P < 0.0001; Figure 4B). No differences were obtained in other positions (B: F = 8.157, df = 2, 27, P = 0.002; C: F = 1.287, df = 2, 27, P = 0.293; D: F = 11.532, df = 2, 27, P < 0.0001; Figure 4B) between the top- and bottom-lighting treatments. However, the aphid distribution was different in the no-light treatment. Less than 3% of aphids were not on plant in the two lighting treatments (bottom lighting: 3%; top lighting: 1%), while 42% failed to find their host without light; the difference was significant (F = 6.592, df = 2, 27, P = 0.005; Figure 4B).
Figure 5. The set-up of the phototaxis experiment of Acyrthosiphon pisum: for phototactic response in different stages and wing forms of Acyrthosiphon pisum (A); for phototactic response with different wavelengths (B); for gravitaxis of A. pisum (C); and for distributions under different lights (D).
The distribution of wingless adults on hosts was also strongly affected by light (Figures S1A,C). Numbers of aphids were different in positions B and D (marked on Figure 5D); more aphids aggregated at the lighting source (A: F = 18.118, df = 2, 27, P < 0.0001; B: F = 12.427, df = 2, 27, P < 0.0001; C: F = 1.586, df = 2, 27, P = 0.223; D: F = 1.917, df = 2, 27, P = 0.167; Figure 4C). Nearly 29% aphids did not find their host without light, and most or all aphids (bottom lighting: 5%; top lighting: 0%) moved to the plant in the top lighting treatment (F = 76.649, df = 2, 27, P < 0.0001; Figure 4C). Numbers of aphids unable to find their hosts in the no lighting treatments for all treatments. More wingless aphids found their host plants than the winged adults without light (F = 12.296, df = 2, 27, P < 0.0001; Figure 4D).
Our experiments showed that winged A. pisum could actually change their phototaxis during their development, and this change can assist aphids in dispersal and host distribution. We found that wingless pea adults showed positive phototaxis while winged adults could change phototaxis from strongly positive to negative depending on their breeding situation. Adults in their reproduction period could regain their phototaxis to positive under starvation. Different morphs showed different reactions to different light wavelengths. We speculated that the dopamine modification pathway was related to phototactic behaviors. These behaviors might assist the aphid to optimize its distribution on host plants
Insects can react to some physical stimuli for environmental adaptation. Phototaxis is one of these behaviors that can be stimulated by light signals (Bowden, 1982; Miller and Hadfield, 1986; Summers, 1997; Briscoe and Chittka, 2001). We found that the pea aphid could also show phototaxis (Figure S1B). The wingless and winged nymphs and wingless adults showed only positive phototaxis (Figure 1A). These results were similar to the studies of Hajong and Varman (2002) on Sitobion rosaeiformis. But we also detected that winged adults could change their phototaxis, and these changes were related to their fecundity; the more nymphs they laid the stronger preference for dark they show (Figure 1B). This special behavior appears unique to the winged A. pisum adults.
Dopamine and serotonin pathways have been reported in phototaxis modification (McPhee and Wilkens, 1989; Pires and Woollacott, 1997; Neckameyer et al., 2001; Riemensperger et al., 2011). In our investigation, we found that dopamine might be altering phototaxis. Only 8-day-old winged adults showed down-regulation in DDC, and they also showed slight negative phototaxis. Expression levels of DDC in 1-day-old winged adults and wingless adults were relatively higher than 8-day-old winged adults, and both of them represented positive phototaxis (Figures 1A, 2A). It exhibited a connection between DDC expression and phototaxis. This provided similar results to those in D. melanogaster and B. neritina which high dopamine can increase positive phototaxis (Pires and Woollacott, 1997; Neckameyer et al., 2001; Riemensperger et al., 2011). We assumed that dopamine pathway would function similarly in A. pisum as well, and the dopamine pathway downstream (dopamine receptors and dopamine re-uptaking) also need to be studied. In the meantime, we assumed that the octopamine (based on TβH expression) might represent the locomotion abilities in the pea aphids (dispersal winged adult > breeding winged adult > wingless adult), which dispersal winged morphs showed higher regulation than the other two morphs we selected. Serotonin (based on TPH expression) exhibited differences between the wingless aphid and the two winged forms (Figures 2B,C), and the mechanism behind needs to be investigated. Previous studies reported that serotonin could also modify phototaxis (McPhee and Wilkens, 1989; Thamm et al., 2010), but in our experiments we observed no connection between serotonin and phototaxis in the pea aphids (Figures 1A, 2C).
We attempted to reveal the dopamine receptors functions in phototaxis by using dopamine antagonist. The treatment was relatively unsuccessful and no differences were observed in our experiment. But to our surprise, all treated aphids showed a weak response to light. We have noticed that injection (physical injury) could affect dopamine production (DDC expression). It could lead to declining dopamine levels in all injected aphids (aphids feed on the fluid in plant phloem. Due to the difficulty to feed the aphids dopamine antagonists, our results showed that artificial diet (poor nutrition) could also affect dopamine pathway) (Figure 2D). Both of our DDC expression detection of injected and control aphids showed down-regulation, which means all the treated aphids had a decline in dopamine level. This result also supported our assumption regarding the function of dopamine in aphid phototaxis, and the weak negative phototaxis that observed might be caused by dopamine biosynthesis declining. But the multiple functions of dopamine revealed that phototactic behavior is not likely to be simple, and we still need a better way to obtain precise results.
Considering that the winged adult was the only morph that responded to population dispersal and its strong response to light, the changes in phototactic behaviors would affect their movement patterns in winged A. pisum. It is reasonable that the negative phototactic behavior of breeding winged aphids has a special ecological function that related to light signal, and aphids' movement patterns (host distribution) in host was considered as a breakthrough. The results in the spatial distribution of the aphids on plants indicated that positive phototaxis of the wingless aphids could reach plant top. If the light source changed downward, their distribution could be affected. Because the direction of sunlight is normally from above, we assumed that sunlight could be a beacon for aphids to identify where the host top is located and to move toward it. For winged aphids, we believe that the multiple functions of phototaxis could assist other behaviors. Combing with our studies, we hypothesized that in the early stage of winged adults (newly emerged, pre-breeding), strong positive phototaxis could help the aphids reach the top of a plant and fly away. After they found a host and started to develop into breeding winged morphs, positive phototaxis would be unwise, and the aphids need to find a way to keep themselves sedentary. Therefore, based on our results, we assumed that an altering phototaxis could help in solving this problem. On the other hand, if the host was not familiar to the aphids in wild condition, negative phototaxis could help them to walk downward and get away from the immature part (buds and new leaves), which probably have a stronger resistance to aphids or being predated by nature enemies. Starvation normally represents a lack of nutrition, and long duration of starvation could reverse phototaxis, which may lead aphids back to the top position in order to fly away in our opinion. Changeable phototaxis is common in other animals, representing a flexible adaptation to the environment (De Ruiter and van der Horn, 1957; Barrett and Chiang, 1967; Dingle, 1969; Bulkowski and Meade, 1983; Miller and Hadfield, 1986; Ben-Shahar et al., 2003; Gong et al., 2010). Our researches revealed that A. pisum had a similar physiological character. The hypothesis of its ecological functions need more evidences.
Previous studies by Hajong and Varman (2002) in S. rosaeiformis also indicated the involvement of phototaxis in aphid distribution, but this aphid species could reach the host bud without light. We found surprisingly that our tested A. pisum aphids displayed a strong decline in host finding abilities without lighting, and compared with the two winged individuals, wingless aphids showed better host finding ability (Figure 4).
All aphid in the experiment slightly displayed positive gravitaxis (Figure 3). These results showed the importance of light (or vision) in host location for pea aphid. It has been discussed in earlier studies, vision of the insects may be even more important than olfaction in host finding (Reeves et al., 2009; Reeves, 2011; Machial et al., 2012), and our work also supports this finding.
In conclusion, different pea aphid morphs could display different phototaxis to light stimuli, and light in different wavelength bands could also give different stimuli to aphids. We noticed that light in short wavelengths produced strong positive or negative effects on aphids, and light in middle or long wavelength bands had weaker or no effects on them. The tested aphid morphs showed different reactions to specific light wavelengths. Based on previous studies of aphid's vision organs, different eye constructions (compound eyes, and ocelli missing) might be responsible for the differences in reaction to light (Braendle et al., 2006; Brisson, 2010). Dopamine, a neurotransmitter, might play a certain rule between light signal detection and behavioral response in pea aphid.
Winged pea aphids can changes their phototactic responses, which help them to disperse during their pre-breeding period and to prevent them to fly away from the host plants during the period of their reproduction. For the wingless morphs, their positive phototaxis could assist them in locating hosts (Figure 6). We found that the aphids were observed almost unable to locate their host without light so that light signals are extremely important for aphid dispersal and distribution, representing a significant adaptation to ecological environments.
Figure 6. The hypothesis of phototaxis functions in different Acyrthosiphon pisum morphs. Winged aphids can change their phototactic responses, which help them to disperse during their pre-breeding period and to prevent them to fly away from the host plants during their reproduction period; for the wingless morphs, their positive phototaxis could assist them in locating best parts of host plants.
Author Contributions
YZ and TL designed the research; YZ and XW performed research; XJ and HT provided assistance; YZ, XW, and HT analyzed data; YZ and XW wrote the manuscript; XJ, HT, and TL edited the manuscript; and XW and YZ revised the manuscript.
Conflict of Interest Statement
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
This work was supported by the National Key Basic Research Program of China (973 Program) (No. 2013CB127600). We are grateful for the assistance of all staff and students in the Key Laboratory of Applied Entomology, Northwest A&F University at Yangling, Shaanxi, China.
Supplementary Material
The Supplementary Material for this article can be found online at: https://www.frontiersin.org/article/10.3389/fphys.2016.00307
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Keywords: phototaxis, distribution, dopamine, insect behavior, Acyrthosiphon pisum
Citation: Zhang Y, Wang X-X, Jing X, Tian H-G and Liu T-X (2016) Winged Pea Aphids Can Modify Phototaxis in Different Development Stages to Assist Their Host Distribution. Front. Physiol. 7:307. doi: 10.3389/fphys.2016.00307
Received: 25 May 2016; Accepted: 06 July 2016;
Published: 02 August 2016.
Edited by:Sibylle Carmen Stöckli, The Research Institute of Organic Agriculture-FiBL, Switzerland
Reviewed by:Marianna I. Zhukovskaya, Russian Academy of Sciences, Russia
Pavel Kindlmann, Charles University, Czech Republic
Copyright © 2016 Zhang, Wang, Jing, Tian and Liu. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
*Correspondence: Tong-Xian Liu, email@example.com
†These authors have contributed equally to this work.


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subset: commoncrawl


text:
[Image courtesy of feelnumb]
I've covered the issue of special elections a lot recently, focusing especially on the financial burden they can place on election offices. Last week, though, Illinois' Marshall County opened up a new front in the battle to cover election costs, sending a letter to resigning U.S. Rep. Aaron Schock asking that he use some of his remaining campaign funds to cover the county's costs to replace him. The Peoria Journal Star has more:
The Marshall County Board wants former U.S. Rep. Aaron Schock to pay the $76,000 in unbudgeted county costs for special elections to fill the 18th Congressional District seat he abandoned.
The board voted unanimously Thursday to send the Peoria Republican a letter [link here] requesting the reimbursement. Schock resigned last month following controversy over his use of taxpayer and campaign funds.
The costs for the special primary and general election have been estimated at $38,000 each, officials said. In a vein somewhat similar to a collection letter, the board offers Schock options of sending either the full amount or an agreement stating that he will pay later.
"If you choose to forward an agreement, we will provide an itemized statement of the costs following the election," states the letter signed by all 10 board members present at the end of the meeting. "If you choose to send the $76,000 requested, we will accept it on behalf of the citizens of Marshall County as payment in full for the costs of the special election."
It's especially striking that the letter was unanimous – suggesting that whatever partisanship might exist in the race to replace Schock, there is bipartisan agreement that he should help pay for the election to do so.
In addition, Marshall County's letter may be setting the stage for other affected counties to send their own requests for payment:
Chairman Gary Kroeschen and State's Attorney Paul Bauer said discussions of sending such a letter started before a recent Journal Star column by Phil Luciano suggested Schock use his $3.3-million campaign fund to cover such costs. Luciano quoted a former federal election official stating Schock could use the money for that purpose.
"Schock has more money (in that fund) than the county has in its reserves," Bauer said.
Copies of the letter will also be sent to various other officials, including the 20 other voting entities in the 18th District.
"There are other counties who are interested, and they're kind of waiting on someone to step forward," Kroeschen said.
"So we're going to be ground-breakers?" asked member Brad Lindstrom.
That's the right way to put it, Tazewell County Board Chairman David Zimmerman said. He has been outspoken about the costs associated with the election, and had spoken with Kroeschen about the issue.
"You know what, they really are (ground-breakers)," Zimmerman said. "I tip my hat to them for that."
Zimmerman, whose county is expected to incur costs of around $200,000 for the elections, said a Tazewell committee will discuss the topic on April 22, followed by possible board action a week later. He said he hoped Marshall County's action leads others to take similar steps.
The County knows its request isn't legally binding, but is proceeding nonetheless:
Kroeschen … noted the county has no power to compel payment.
"I don't know if we'll get any money," he said.
But if Marshall County inspires others, increased attention to the financial hardships caused by the special election might eventually get results, Zimmerman observed.
"I really think it's the right thing to do," Zimmerman said. "Even a partial reimbursement would help."
I'll be curious to see if this approach works; if nothing else, it's highlighting the problem created for localities by special elections – and suggesting a new way for them to get a little help from the very individuals who create the vacancies in the first place.
This one is fascinating – stay tuned …


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Litlefjellet Hiking Trail
Don't miss this quick hike with knockout views
Essential info
- Destination: Romsdalen
- Season: April-October
- Difficulty: Easy
- Distance: 1.3 kilometers (out‑and‑back)
- Elevation Gain: 140 meters
- Duration: 1-2 hours
About Litlefjellet
Litlefjellet is a short, easy hike and one of the most accessible natural viewpoints in the area. It is an excellent vantage point from which to admire Trollveggen (the Troll Wall). With a sheer one kilometer precipice and its collection of jagged peaks, the wall is one of the most famous sights in Norway.
Reaching 780 metres above sea level, Litlefjellet (Little Mountain) sits directly across the valley from the wall. Litlefjellet also gets you up close to Romsdalshornet, a distinctive peak popular with mountain climbers.
Getting there
The trailhead is located in the Vengedalen Valley, a 20 minute drive from Åndalsnes.
From Åndalsnes, drive towards Isfjorden and then follow the signs to Liabygda, and eventually to Venjedalen. There is an automatic toll which is payable by card only. Drive almost all the way to the end of the road, where there is clear signage and parking for Litlefjellet.
The Litlefjellet trail starts just up the road from the trailhead for the famous Romsdalseggen Ridge.
Trail description
From the road, follow the signs up towards the ridge above. A brief 20-30 minute hike along a well-worn, rocky and dirt trail involves some minor scrambling with chains to help you up a couple of short, steep sections.
After reaching the top of Litlefjellet you will find yourself on a ridge between the imposing Romsdalshorn and Blånebba mountains. At your back is Store Venjetinden, a beautiful mountain in its own right with an array of spiked peaks. The ridge offers front-on views of Trollveggen across the valley.
You can explore the ridge, finding different angles from which to admire Romsdalen valley, the colorful Rauma river and its sandy beaches, and down towards Åndalsnes. Some small ponds provide opportunities for interesting photos reflecting the surrounding scenery.
Where to stay
There are several hotels, lodges, and campgrounds in and around Åndalsnes.
- Hotel Aak is a cozy boutique hotel with wonderful food, located about 5 kilometers from Åndalsnes
- Hotel Bellevue is the largest hotel in town and has an in-house restaurant
- Trollveggen Camping has modern cabins and campgrounds, right alongside Trollveggen
Questions or comments? Let us know.
Nearby adventures
Last updated:


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BIR Form 2551Q, or also known as Quarterly Percentage Tax Return are taxes imposed on individuals/businesses who sells/lease goods or services which are exempted from Value Added Tax (VAT) with annual sales not exceeding 3,000,000 PHP.
Be able to generate your 2551Q return in JuanTax by following these instructions:
Before you generate your 2551Q report, you first need to configure your reports as they're intended for Percentage Tax during organization setup.
To generate your percentage tax report, just go to the Percentage Tax Return section in your dashboard, then proceed to 2551Q tab.
then start adding your report by clicking the Generate Report (+) icon.
Choose the year and quarter(month) of your percentage tax report, then click the Generate button to add it in your list of reports.
In Summary tab
For the Total Amount Payable/(Overpayment), there is a section wherein once the amount goes negative, you need to choose whether the overpayment shall be used for either (1) To be refunded or (2) To be issued a Tax Credit Certificate.
In JuanTax, all you need to do is go to Summary and proceed to Section 20A) Creditable Percentage Tax Withheld Per BIR Form No. 2307 and click the Add button.
Enter the amounts in the fields and hit Save.
Once entered, you will encounter this window where you will need to allocate the overpayment. Choose the necessary radio button to continue.
See a preview of the report by going to the Report tab.
Filing the Report
Simply file your report by following the guidelines mentioned in this article through our Help site.
Paying the Return
Follow the steps in this article for you be to able to pay your filed tax return in JuanTax.


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Property Location
With a stay at Hotel Palacio Azteca in Tijuana, you'll be convenient to Plaza Rio Commercial Center and Club Campestre Golf Course. This family-friendly hotel is within close proximity of Hidalgo Market and Paseo Chapultepec.
Make yourself at home in one of the 201 air-conditioned rooms featuring flat-screen televisions. Complimentary wireless Internet access keeps you connected, and cable programming is available for your entertainment. Private bathrooms with shower/tub combinations feature complimentary toiletries and hair dryers. Conveniences include phones, as well as safes and desks.
Don't miss out on recreational opportunities including an outdoor pool and a fitness center. Additional features at this hotel include complimentary wireless Internet access, concierge services, and babysitting/childcare (surcharge).
Enjoy a meal at a restaurant, or stay in and take advantage of the hotel's room service (during limited hours). Quench your thirst with your favorite drink at a bar/lounge. Buffet breakfasts are available for a fee.
Business, Other Amenities
Featured amenities include a business center, complimentary newspapers in the lobby, and dry cleaning/laundry services. Event facilities at this hotel consist of conference space and meeting rooms. Free valet parking is available onsite.


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Stakeholders and national experts directly involved in Cedefop's thematic country reviews (TCRs) on apprenticeships took part in the first policy learning forum on apprenticeships on 7 and 8 September in Thessaloniki.
Stakeholders and national experts directly involved in Cedefop's thematic country reviews (TCRs) on apprenticeships will take part in the first policy learning forum on apprenticeships on 7 and 8 September in Thessaloniki.
Seven members of the Swedish Retail and Wholesale Council's secretariat and Skills and Occupations Committee visited Cedefop on 30 March. Discussions focused on European vocational education and training (VET) policy and Cedefop's work on skills and qualifications.
In November 2016 the OECD presented an in-depth analysis of Sweden's system for skills assessment, anticipation and response. Even though Sweden has become a leader among OECD countries in collecting information on current and future skills needs, several areas of improvement have been identified to tackle skills mismatch.
Skills for confident and conscious use of information technology are becoming increasingly important in a changing society. In IVET, digital competence may be crucial for learners to adapt in a competitive economy. To promote digital competence, the Swedish government is proposing a strategic nationwide programme that takes IVET-specific needs into account.
The year 2016 has been declared the Swedish Year of vocational education and training (VET). Many activities will highlight vocational education and training, and, for the first time, a major international skills competition, EuroSkills, will be held in Sweden.
Sharing common challenges but different experience, encouraging dialogue between policy makers and practitioners, and involving different stakeholders have been the leading principles of the three year project Learning at work. The final dissemination conference in December 2015 gathered representatives from all Nordic countries including the Faroe Islands and Åland. Building on this experience, cooperation and exchange will continue among stakeholders and countries.
In November 2015 a national conference of stakeholders from education, social partners and other organisations marked the launch of the Swedish national qualification framework (SeQF).
In 2011, Swedish upper secondary education was reformed. The current system consists of twelve vocational education and training (VET) programmes and six higher education preparatory programmes. These cover 2500 study points and are divided into several orientations.


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Gorgeous high waisted firm control panty girdle which moulds and shapes in all the right places - a flatter tummy, shapely bottom and a slimmer waist. 1" wide comfort fit waistband, with 3" light boning at the back which offers support and stops it rolling down. Separate overlay panels with a choice of 3 settings of hook and eye fastenings to the front giving it the appearance of a corset, bringing sexy into shapewear.
Available in Black.
XL: UK 10-12 (Waist 30-32" / 79-85cm)
XXL: UK 12-14(Waist 32 -34" / 80cm -87cm)
XXXL: UK 14-16 (Waist 34 -36" / 88cm-94cm)
Material: 90% Nylon, 10% Spandex
Wash: Hand wash in warm water or cool machine wash, low spin. Do not tumble dry
When choosing your size, it is advisable to go for the bigger size if you are at the max measurement - i.e. for a 31" waist, choose Large unless you want an extremely tight fit.
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Friday, July 31, 2009
Windows of the lovely Astor Hotel
They can be seen on the Duane Avenue and 14th Street sides of the Astor Hotel in Astoria, Oregon. The building was constructed after the 1922 fire burned down its predecessor. I wouldn't know what to call the style. I called the building Art Deco based on various features and the look of its Commercial Street side opposite (shown here). If anyone can help me out with the style, I'd be very interested in what you have to say. I love architecture and styles, but this one isn't 100% in my vocabulary. One author called it "Gothic," and I didn't see that at all on the other side of the building, but these windows bear a hint of Gothic, if only a hint. As to the old hotel itself, several comments from the last post are worth printing here. Some were made on Blogger, and some on the Facebook page for this blog. By the way, I left two small heads at the bottom of the photo for scale and reference. I tried cropping, but I kinda like them there.
Branden Wilson: Don't forget that the top few floors are not even original. They were an afterthought built on years later . . .
Julie Winlund Evans: The bus depot was on the ground floor and I can remember watching the wooden 'dock' rot away over the years as the blackberry briars took over.
Kurt Hanson: I remember the ballroom, it was totally awesome and the little cafe on the corner where the toy store is/was? I also remember the bus depot - I can,t remember what year that was late 60's?
Lee Spangler: What is also cool is what is left of the interior of the main floor. We'll sneak in next weekend.
So, perhaps we'll have additional photos coming up. There's also a comic and game store on the corner of Commercial and 14th with a sign worthy of a photo. I'll see what I can do with that one some time!
There's a bit of sky here, and I like taking part in Skywatch Friday, but I have to admit that the photo was taken last Sunday when the sky was blue and the weather was glorious. That was just before the heatwave. Now the heat has been followed by the marine layer's inevitable clouds, and today so far it's completely overcast. It rained last night, it's cool today, and I'm not complaining!
9 comments:
- Wieneke said...
Hello, I was looking at these windows and I had to think about some Arabic influences... but I cannot help you about the name of this style. Anyhow, I think it wonderful. Greetings from the Netherlands.
- July 31, 2009 at 12:18 PM
- cieldequimper said...
It looks more like art déco to me than gothic. It's lovely!
- July 31, 2009 at 12:25 PM
- The Laughing Idiot said...
My first inclination was that it's a hybrid of moroccan and gothic style. What would you call that - gothican, morothic?
Beautiful photo of the hotel.
Please visit me: Picture This . . .
- July 31, 2009 at 1:15 PM
- Vogon Poet said...
I agree with ciel, it's art déco. It reminds me of two buildings of about the same period: the General Electric Building and the American Standard Building in New York City.
Try: Art Deco in NYC
- July 31, 2009 at 5:42 PM
- Jacob said...
I think they're called "An architect's delight." ;-)
I do like 'em, though!
- July 31, 2009 at 6:23 PM
- Don and Krise said...
I'm wondering when you go inside if there will be some historic info. Often they will post the history of old buildings somewhere in the entry.
- July 31, 2009 at 11:30 PM
- Small City Scenes said...
It actually looks very institutional--well from long ago. and then maybe it's just the gray color or is that white? Interesting anyway. MB
- August 1, 2009 at 6:34 PM
- Sueso said...
I'm wracking my brain and if I remember right, the John Jacob Astor Hotel was originally pink..not that long ago (80's?) it was remodeled for senior living! I think that's when they changed the color. My sister actually spent her wedding night there in the early 50's! It was THE place to go and quite fancy. Later in the 60's we used to have lunch there quite often after riding the ferry from across the river to go shopping in Astoria! Sue@Seaside
- January 3, 2011 at 3:41 AM
- AntiquityTravelers said...
Most of the buildings in downtown Astoria (Commercial street) are dated 1922 or later. There were 2 massive fires, the second of which leveled the downtown in 1922 (for the second time). The downtown was originally built on a dock with pilings. After the second fire they did landfill and rebuilt the downtown with cement and brick.
The original building was supposed to be 5 stories, but after the fire (which happened during its construction) they built 8 stories to deal with the housing issue of fire victims.
Likely style during this period would be Art Deco - if these are the original windows.
In 1968, the hotel was condemned as a fire and safety hazard and closed. The "pink elephant" stood vacant for 10 years with ragged curtains flapping out of broken windows.So it is possible that these were not the original windows.
- August 22, 2012 at 7:03 AM


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Affordable Christmas Gifts
Mrunmayi Deo
Dec 20, 2018
Going for some affordable Christmas gifts for the occasion is a nice way to make it all the more economical, yet memorable.
Have you been searching for some good, affordable Christmas gifts for your family members and friends for a long time now? You are really tensed, since Christmas is soon to come and you are absolutely empty-handed without a single gift at your end.
Then what? To worsen, you don't have much of cash to spend this time around as you had the previous year. So, the bottom line is, you are in a big fix. Do not worry, we will help you go about it in an easy manner and help choose the right kind of gift as well. Make your choice from the list of inexpensive ideas given ahead.
Chocolate Gift Baskets
Well, this is the best family idea for this occasion. What you could do is make homemade chocolates, wrap them with different-colored aluminum foils, and place them in cute baskets. You can buy the gift baskets from nearby stores. They aren't expensive.
For making chocolates, you would need dry fruits, and ready-made cocoa powder, that's it! Chocolates would be loved by kids and adults alike, so go ahead with this idea. Alternatively, you could make some delicious Christmas cookies or cupcakes to replace the chocolates.
Christmas Cards
Another idea is to make Christmas cards at home itself. Now, for this, you would need to buy the decorative material and paper from the stores along with color chalks and sketch pens.
If you are artistic and love drawing or painting, then explore your skills and go ahead with this. Along with the greeting, you could write a letter for the person you are making the card for, and this is sure to make their day special.
Memory Albums
What better could it be, than to pile up some best captured moments all together in an album!
For this, buy a journal or a big notebook album, choose some best photographs, say with family or friends or a special someone, and stick them up in the album as per your wish. You could also write some quotes or experiences, which you remember very evidently.
Alternatively, you could also make an album of the fun times during the previous Christmas years in a year wise format. This is, in my opinion, the best creative present you could gift anyone.
Winter Clothing
If you know how to knit or sew, then you could make a muffler, a cape, or a scarf for your siblings, friends, or your parents. However, remember, you would need to start off pretty early so that you complete it on time.
Instead of buying expensive winter coats, hand-stitched thermals would be appreciated more, and would prove to be useful, and certainly the best gifts for men and women alike.
Instead of shelling out too much of cash, it would be better to make use these homemade ideas and surprise one and all. Along with this, plan a nice cozy dinner with your family and friends by making some unique Christmas recipes. Merry Christmas!
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Tyseley Refuelling Hub
The low and zero carbon refuelling station on Tyseley Energy Park will be unmanned with 24/7 refuelling available. Pay at pump option will be integrated into the dispenser display head at each refuelling point which will accept credit, debit and fuel card payments. Refuelling facilities at TEP will include Hydrogen, Compressed Natural Gas, Biodiesel and electrical charging options.
The hydrogen will be produced on site using a 3MW ITM Power Proton Exchange Membrane (PEM) electrolyser, which splits water into hydrogen and oxygen, eliminating the requirement for deliveries, and therefore generating a clean fuel. The fuel is produced using a 3MW ITM Power Proton Exchange Membrane (PEM) electrolyser, which splits water into hydrogen and oxygen. The hydrogen generated is very high purity, meeting all requirements for Fuel Cell Electric Vehicles (FCEVs). The hydrogen is dispensed at 700bar and 350bar ensuring a very quick and efficient refuel that can provide a 300-350 mile range. When hydrogen is used in a fuel cell, it returns back to water vapour, meaning hydrogen as a fuel is a very clean fuel option.
For more information please see: http://www.itm-power.com/ or email [email protected]com
Compressed Natural Gas
CNG can be used by HGVs as an alternative to diesel. A CNG refuelling station operates by extracting gas from a natural gas pipeline, compressing the gas by using on-site compressors and then dispensing it into trucks. By displacing diesel with bio-CNG a 90% reduction in CO2 emissions compared with a diesel truck is achieved. CNG also helps reduce harmful particulate emissions from engines and CNG vehicles also run approx. 50% quieter than a comparable diesel vehicle. The pumps will be fully automated, self-service operated.
For more information please see http://www.cngservices.co.uk/
Shell GTL
The Certas Energy state-of-the-art bunker provides a convenient place for HGV operators to refuel on diesel, gas oil and Adblue via eight high-speed pumps.
The facility will be the second refuelling bunker in the country to dispense Shell GTL Fuel, offering a cleaner burning, drop-in alternative to diesel for on-road and off-road applications. The use of Shell GTL Fuel immediately lowers emissions of harmful pollutants such as nitrogen oxides (NOx) and particulate matter (PM). The fuel also delivers additional performance benefits for vehicles operating in built-up urban areas, such a reducing fuel odours and engine noise levels. Shell GTL Fuel will also power the site's truck wash facility for large vehicles.
For further information on the fuel options available from Certas Energy please contact [email protected]
Electric Charging
Improved vehicle design and battery performance and falling prices is enabling widespread electric vehicle market penetration. This combined with policy support and restrictions on other vehicles to improve air quality, such as Birmingham's Clean Air Zone will increase this momentum even further.
Tyseley Energy Park will offer a range of electric charging facilities including 150kW electric vehicle rapid chargers. Vehicle and fleet owners will be offered a lower cost electric charging unit price if they commit to a defined dwell time at the charging points.
For further information on electric charging available please contact [email protected]
Additional Information
Tyseley Energy Park is providing a series of business engagement events. For further information please contact us at [email protected]
For further information about the latest vehicle technology visit http://www.energysavingtrust.org.uk/transport-travel/transport
For further information about the HGV vehicle wash facility provided on site please contact [email protected]


text: Washington - Construction of new homes in the United States sprang to life in October as hurricane-damaged housing markets recovered from back-to-back late summer storms. The spike in construction, which also reflected a large increase in apartments in regions not touched by Hurricanes Harvey and Irma, was the biggest in a year and followed three consecutive months of declines, the Commerce Department reported.Analysts say supply in the tight US housing market has failed to keep pace with demand and it remained unclear whether the October bounce could be sustained once the storm effects recede.Housing starts rose 13.7% to a seasonally adjusted annual rate of 1.29 million units, the largest increase and the highest level since October 2016. The result far overshot analyst expectations, which had called for a more modest 5.6% increase.The sudden jump followed months in which construction slowed and last month's pace was still 5.3% below the rate recorded in October of last year.And Ian Shepherdson of Pantheon Macroeconomics said the October jump might be noise from the hurricanes."It would still be a real stretch to argue that the trend is rising," he wrote in a client note. "All we can say for sure is the hurricane hit has reversed."Construction of apartments surged 37.4%, the largest increase since December, driven in large part by new construction in the Northeast. In that region homebuilding shot up by 44.2%, while single-family homes saw a 22.4% drop.In the South, which includes flooded and storm-battered southeast Texas and Florida, single-family home construction rose 16.6%, its fastest pace in more than three years.Building permits, which are a sign of construction in the works, gained a less robust 5.9% compared to September, reaching an annual rate of 1.29 million units, the highest level since January.*Sign up to Fin24's top news in your inbox: SUBSCRIBE TO FIN24 NEWSLETTER


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Data is always crucial to the people. A person, may be a student or an employee gives much importance to his/her data. But most of the people does not know that there can be some unpredictable situations that might cause their data inaccessible. It means that there are scenarios beyond your control that may happen without your knowledge. Data backup is the most important thing for those who wants to keep their data safe forever. Data Backup is nothing but a copy of the original data. So, it is always recommended to have a backup copy of your important data. For many people Backing up data may sounds like an advanced, overwhelming task. But it is not as complicated as you are thinking.
Now, the question is What kind of data you have to backup?
You can take backup of your general documents like word documents, pdf files, personal notes and configuration files. Your backup may also include music, movies, photos, and more... in other words you can backup Everything that is stored on your PC.
But you should remember that backup needs storage space. This isn't a big deal for small files like Word and PDF documents or configuration settings. But, in case if you want to back up your photos, music and video collections that are dozens or hundreds of gigabytes large, then you're really limited in where those backups can be stored. If you have more data to backup then you have to spend more time on it. So, I suggest you to select the data that is important for you.
There are various tools available for data backup which can used to backup the files, folders, partitions and even operating system. You can also use cloud storage like Dropbox or Google Drive. Your files are automatically synchronized between your computer and the cloud storage. This is effectively a method for making automatic backups — your computer's files are periodically copied to the Internet.
In this post, I have illustrated how to use Google Drive. Later I will post how to use other backup software.
Here, I have mentioned the steps to use the cloud storage - Google Drive provides 15GB of free storage space.
Method 1:
1. Create a new or use your existing google account to login to drive.google.com
2. Click on New button on the left pane and select Folder option to create a new folder to store your files.
3. Give a name to the folder and click on Create button.
4. Now you can see a folder you have created in My Drive area. Double click on the folder to open it.
5. Now you can drag & drop or upload your files into the folder on the google drive.
Method 2:
If you want to upload or access the files while you are offline, then you can install and use Google's Get Drive for PC application.
Let us go through the steps to install and use this tool. 1. At the bottom-left of the Drive screen you can find Get Drive for PC option.
2. Then click on Download Drive --> Mac and PC option.
3. Click on Accept & install
4. When prompted click on Save button.
5. Now install the downloaded tool "googledrivesync.exe"
6. Click on Next ---> Next ---> ---> Next ---> Done.
7. Click on Get Started
8. You can find and access the Google Drive in File Explorer's left pane.
Now you can copy your files into it, so they can be synced with google drive. You can use this application to access your files and folders even if you are offline.
If you face any problem while using Google Drive, feel free to comment or Contact Me.


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!! History Commons Alert, Exciting News
A number of pilots with the 102nd Fighter Wing at Otis Air National Guard Base in Massachusetts are preparing to take off for a training mission and see two of their unit's fighter jets being scrambled in response to the hijacked Flight 11, but they are not asked to respond to the emerging crisis themselves and continue with their preparations for the training mission. [102nd Fighter Wing, 2001; Richard, 2010, pp. 9-12] Pilots Preparing for Training over the Atlantic - The pilots are preparing to fly a defensive counter-air mission in an area of military training airspace over the Atlantic Ocean, southeast of Long Island, known as "Whiskey 105." [Richard, 2010, pp. 10, 12; Airman, 9/3/2011] According to most accounts, six of the 102nd Fighter Wing's F-15 fighters will be participating in the training mission. [102nd Fighter Wing, 2001; North American Aerospace Defense Command, 9/11/2001; Cape Cod Times, 9/11/2006; Spencer, 2008, pp. 155] But Major Martin Richard, one of the pilots involved, will write in a 2010 book that eight of the unit's F-15s take part in the mission. Richard will recall that after the coordination briefing for the training mission, he goes to the "life support shop" and puts on his flying gear, and then goes to the operations desk. There, the unit's supervisor of flying, Lieutenant Colonel Jon Treacy, briefs the pilots preparing for the training mission on current weather and airfield updates, and gives them the status of a KC-135 tanker plane that will be refueling their fighters during the training mission. Richard then heads to his F-15, inspects it, and speaks to his crew chief. Pilots Notice Commotion as Fighters Are Scrambled - As Richard starts his fighter's engines, he notices a commotion on one side of the flight line ramp. He will recall: "The broken, disjointed communication over the ultra high frequency (UHF) radio indicated confusion. Members of the 102nd Security Forces Squadron, the cops, marshaled into protective positions. Two vehicles appeared with their blue emergency lights flashing. We all knew what was going on." The 102nd Fighter Wing keeps a pair of F-15s on alert—armed, fueled up, and ready to take off within minutes of a scramble order—and, Richard will recall, "[T]he alert aircraft were being scrambled." [Richard, 2010, pp. 10-11] Pilots Watch Alert Fighters Take Off, but Unconcerned about This - The pilots preparing to take off for the training mission idle their engines and wait while the two alert fighters take off (see 8:46 a.m. September 11, 2001). [102nd Fighter Wing, 2001] Richard will describe: "I watched from my jet as the clamshell doors on the alert hangars opened, heard the alert jets' engines whine to life, and saw them aggressively emerge from the facility like an eager predator in search of its prey. Suddenly, the command post announced, 'Scramble!' They blasted off, shattering the previously still, calm, peaceful morning." [Richard, 2010, pp. 12] The pilots involved in the training mission are apparently unaware of why these fighters are being scrambled. [Cape Cod Times, 9/11/2006] Richard will recall: "I wasn't too concerned when I saw the scrambled aircraft take off. We see many scrambles during the year and most all are just aircraft or vessels that can't be identified but are friendly." [102nd Fighter Wing, 2001] Pilots Continue Preparing for Training - Once the two alert fighters are airborne, the pilots on the ground continue preparing for their training mission. "Back on the flight line," Richard will recall, "I arranged my formation for takeoff and followed the standard procedures en route to our training area southwest of Martha's Vineyard." [Richard, 2010, pp. 12] Richard and the other pilots will begin their training mission in Whiskey 105 (see (9:00 a.m.-9:24 a.m.) September 11, 2001). They will only learn of the first crash at the World Trade Center and be recalled to their base at around 9:25 a.m. (see (9:25 a.m.-9:45 a.m.) September 11, 2001), and some of them will take off again to help protect US airspace, but that will only be after the terrorist attacks have ended (see (10:30 a.m.) September 11, 2001 and (Shortly After 10:30 a.m.) September 11, 2001). [102nd Fighter Wing, 2001; 9/11 Commission, 10/14/2003 ; Spencer, 2008, pp. 244-246] Unit's Mission Is to Protect Northeast US - The 102nd Fighter Wing at Otis Air Base, according to its own statement, has aircraft and their crews "on continuous 24-hour, 365-day alert to guard our skies." The unit says its "mission is to protect the Northeast United States from armed attack from another nation, terrorist attack, and activities such as smuggling, illicit drug activity, and illegal immigration." Its large area of responsibility includes "the major industrial centers of Boston, New York, Philadelphia, Detroit, and all national command centers in Washington, DC." [Cape Cod Times, 9/12/2001] The 102nd Fighter Wing is equipped with 18 F-15 Eagles, including the two that are kept on alert. [Boston Globe, 9/15/2001; Cape Cod Times, 9/21/2001]
Entity Tags: Jonathan T. Treacy, Martin Richard, 102nd Fighter Wing
Timeline Tags: Complete 911 Timeline, 9/11 Timeline
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