A Mechanistic Approach to Investigate Drilling of UD-CFRP Laminates with PCD Drills

Cataloged from PDF version of article.Carbon fiber reinforced plastics (CFRPs) possess desirable material properties that satisfy the aerospace industry's high strength to weight ratio objective. Therefore, CFRPs are commonly used in structural parts, either alone or together with aluminum and titanium alloys. Drilling of CFRPs has been studied extensively in the literature in recent years, with special emphasis on process parameters and delamination. This study identifies mechanical properties of uni-directional CFRPs through drilling tests. Drilling of uni-directional CFRP plates with and without pilot holes has been performed, and cutting and edge force coefficients are identified. A polycrystalline diamond (PCD) drill was used in tests since this type of drill is commonly used in practice. Finally, validation tests on multi directional CFRP laminates have been performed and good results have been obtained. (C) 2014 CIRP

PDK1 and HR46 Gene Homologs Tie Social Behavior to Ovary Signals

The genetic basis of division of labor in social insects is a central question in evolutionary and behavioral biology. The honey bee is a model for studying evolutionary behavioral genetics because of its well characterized age-correlated division of labor. After an initial period of within-nest tasks, 2–3 week-old worker bees begin foraging outside the nest. Individuals often specialize by biasing their foraging efforts toward collecting pollen or nectar. Efforts to explain the origins of foraging specialization suggest that division of labor between nectar and pollen foraging specialists is influenced by genes with effects on reproductive physiology. Quantitative trait loci (QTL) mapping of foraging behavior also reveals candidate genes for reproductive traits. Here, we address the linkage of reproductive anatomy to behavior, using backcross QTL analysis, behavioral and anatomical phenotyping, candidate gene expression studies, and backcross confirmation of gene-to-anatomical trait associations. Our data show for the first time that the activity of two positional candidate genes for behavior, PDK1 and HR46, have direct genetic relationships to ovary size, a central reproductive trait that correlates with the nectar and pollen foraging bias of workers. These findings implicate two genes that were not known previously to influence complex social behavior. Also, they outline how selection may have acted on gene networks that affect reproductive resource allocation and behavior to facilitate the evolution of social foraging in honey bees

Effects of Insemination Quantity on Honey Bee Queen Physiology

Mating has profound effects on the physiology and behavior of female insects, and in honey bee (Apis mellifera) queens, these changes are permanent. Queens mate with multiple males during a brief period in their early adult lives, and shortly thereafter they initiate egg-laying. Furthermore, the pheromone profiles of mated queens differ from those of virgins, and these pheromones regulate many different aspects of worker behavior and colony organization. While it is clear that mating causes dramatic changes in queens, it is unclear if mating number has more subtle effects on queen physiology or queen-worker interactions; indeed, the effect of multiple matings on female insect physiology has not been broadly addressed. Because it is not possible to control the natural mating behavior of queens, we used instrumental insemination and compared queens inseminated with semen from either a single drone (single-drone inseminated, or SDI) or 10 drones (multi-drone inseminated, or MDI). We used observation hives to monitor attraction of workers to SDI or MDI queens in colonies, and cage studies to monitor the attraction of workers to virgin, SDI, and MDI queen mandibular gland extracts (the main source of queen pheromone). The chemical profiles of the mandibular glands of virgin, SDI, and MDI queens were characterized using GC-MS. Finally, we measured brain expression levels in SDI and MDI queens of a gene associated with phototaxis in worker honey bees (Amfor). Here, we demonstrate for the first time that insemination quantity significantly affects mandibular gland chemical profiles, queen-worker interactions, and brain gene expression. Further research will be necessary to elucidate the mechanistic bases for these effects: insemination volume, sperm and seminal protein quantity, and genetic diversity of the sperm may all be important factors contributing to this profound change in honey bee queen physiology, queen behavior, and social interactions in the colony

Down-Regulation of Honey Bee IRS Gene Biases Behavior toward Food Rich in Protein

Food choice and eating behavior affect health and longevity. Large-scale research efforts aim to understand the molecular and social/behavioral mechanisms of energy homeostasis, body weight, and food intake. Honey bees (Apis mellifera) could provide a model for these studies since individuals vary in food-related behavior and social factors can be controlled. Here, we examine a potential role of peripheral insulin receptor substrate (IRS) expression in honey bee foraging behavior. IRS is central to cellular nutrient sensing through transduction of insulin/insulin-like signals (IIS). By reducing peripheral IRS gene expression and IRS protein amount with the use of RNA interference (RNAi), we demonstrate that IRS influences foraging choice in two standard strains selected for different food-hoarding behavior. Compared with controls, IRS knockdowns bias their foraging effort toward protein (pollen) rather than toward carbohydrate (nectar) sources. Through control experiments, we establish that IRS does not influence the bees' sucrose sensory response, a modality that is generally associated with food-related behavior and specifically correlated with the foraging preference of honey bees. These results reveal a new affector pathway of honey bee social foraging, and suggest that IRS expressed in peripheral tissue can modulate an insect's foraging choice between protein and carbohydrate sources

Differential Effects of Early- and Late-Life Access to Carotenoids on Adult Immune Function and Ornamentation in Mallard Ducks (Anas platyrhynchos)

Environmental conditions early in life can affect an organism’s phenotype at adulthood, which may be tuned to perform optimally in conditions that mimic those experienced during development (Environmental Matching hypothesis), or may be generally superior when conditions during development were of higher quality (Silver Spoon hypothesis). Here, we tested these hypotheses by examining how diet during development interacted with diet during adulthood to affect adult sexually selected ornamentation and immune function in male mallard ducks (Anas platyrhynchos). Mallards have yellow, carotenoid-pigmented beaks that are used in mate choice, and the degree of beak coloration has been linked to adult immune function. Using a 2×2 factorial experimental design, we reared mallards on diets containing either low or high levels of carotenoids (nutrients that cannot be synthesized de novo) throughout the period of growth, and then provided adults with one of these two diets while simultaneously quantifying beak coloration and response to a variety of immune challenges. We found that both developmental and adult carotenoid supplementation increased circulating carotenoid levels during dietary treatment, but that birds that received low-carotenoid diets during development maintained relatively higher circulating carotenoid levels during an adult immune challenge. Individuals that received low levels of carotenoids during development had larger phytohemagglutinin (PHA)-induced cutaneous immune responses at adulthood; however, dietary treatment during development and adulthood did not affect antibody response to a novel antigen, nitric oxide production, natural antibody levels, hemolytic capacity of the plasma, or beak coloration. However, beak coloration prior to immune challenges positively predicted PHA response, and strong PHA responses were correlated with losses in carotenoid-pigmented coloration. In sum, we did not find consistent support for either the Environmental Matching or Silver Spoon hypotheses. We then describe a new hypothesis that should be tested in future studies examining developmental plasticity

RNA-sequencing elucidates the regulation of behavioural transitions associated with mating in honey bee queens

This study was funded by a BBSRC ISIS grant BB/J019453/1, a Royal Holloway Research Strategy Fund Grant, and a Leverhulme Grant F/07537/AK to MJFB. BPO was supported by Australian Research Council Discovery grants DP150100151 and DP120101915. FM was supported by a Marie Curie International Incoming Fellowship FP7-PEOPLE-2013-IIF-625487 to MJFB. We would like to thank Dave Galbraight (Penn State) and Alberto Paccanaro (RHUL) for support with analysis of RNAseq data and four anonymous reviewers for providing thoughtful insights that helped to improve the manuscript.Peer reviewedPublisher PD

The effects of hive type and wintering methods on wintering losses in honeybee, A. mellifera L., Colonies in Erzurum conditions [Erzurum Koşullarindaki Balarisi, Apis mellifera L., Kolonilerinde Kovan Tipinin ve Kişlatma Yöntemlerinin Kişlatma Kayiplarina Etkileri]

This research was carried out to investigate the effects of hive type and wintering methods on wentering losses in honeybee, A. mellifera L. colonies in wooden and styrofoam hives in Erzurum conditions and to determine suitable wintering model for this region. Wooden hives for the treatment groups of A, B and C and styrofoam hives for the treatment groups of D, E and F were used in this study. The colonies in groups of A and D wintered outdoor, B and E wintered indoor and C and F wintered under a shed. Colonies in group of A and D were taken out of the experiment in second year. The effect of hive type on the average food consumption of colonies during winter was not significant in first year of the experiment, but it was significant (P<0.05) in second year. The effect of wintering method and interaction between hive type and wintering mehod on the food consumption were not significant. On the other hand, the effect of hive type on the population decreases was highly significant (P<0.01) in the first year of the experiment; but it was significant (P<0.05) in second year. The effect of wintering method on population decreases of colonies was highly significant (P<0.01 ) in first year; but it was not significant in second year. However, it was found that the effect of interaction between hive type and wintering method on population decrease was not significant. The average food consumptions of colonies in wooden hives were higher than those of colonies in styrofoam hives, which might be due to less population decrease of colonies in wooden hives. As a result, wooden hives should be used for wintering to reduced the colony losses and bee mortality in the surviving colonies in Ezurum conditions. It was found that overwintering colonies outdoor without taking any precaution was not economic. Wintering colonies indoor or under a shed should be prefered to the wintering outdoor to reduce food consumption and bee losses. Temperature fluctuations during winter period increased food consumption of the colonies considerably

Colony characteristics and the performance of Caucasian (Apis mellifera caucasica) and Mugla (Apis mellifera anatoliaca) bees and their reciprocal crosses

There are seven climatic regions and several honey bee (Apis mellifera) races and ecotypes adapted to these regions in Turkey. The most common and popular bee races are the Caucasian bees (A. m. caucasica), native to northeastern Anatolia, and the Mugla bees (A. m. anatoliaca), native to south-western Anatolia. Both races have desirable characteristics and they are widely used by beekeepers all over the country. We tested the colony characteristics of Caucasian (C x C) and Mugla (M x M) bees and their crosses (C x M) and (M x C) under migratory beekeeping conditions to combine the desirable characteristics of both races and increase honey yield. All the experimental queens were instrumentally inseminated and introduced into five-frame colonies in the spring of 1996. Colonies headed by Mugla queens produced significantly more honey than Caucasians, and M x C crosses produced significantly more honey than other genotypes. Brood production was significantly higher in M x M and M x C colonies. The C x C were the most gentle and the M x C crosses were the most aggressive genotypes. The study shows that honey yield and brood production can be increased significantly with selection and controlled mating

Morphological characters of some important races and ecotypes of Turkish honeybees (Apis mellifera L.) - I

WOS: 000082411300020This study was conducted to determine the morphological characters of some important honeybee (A. mellifera L.) races and ecotypes in Turkey. Experimental samples were collected from 6 different regions such as Central Anatolia Region (Beypazary), North Eastern Anatolia Region (Posof), Marmara Region (Gokceada). Thrace Region (Saray), Aegean Region (Fethiye) and Mediterranean Region (Erdemli). Although 41 morphological characters were measured, twenty one morphological characters such as length of cover hair on tergite 5, width of tomentum on tergite 4, width of stripe posterior of tomentum, index of tomentum, length of proboscis, length of femur, length of tibia, metatarsus length, metatarsus width, length of hind leg, width of tergite3 (longitudinal), width of tergite 4 (longitudinal), body size, width of sternite 3 (longitudinal), length wax plate of sternite 3 (longitudinal), width wax plate of sternite 3 (transversal), distance between wax plate of sternite 3, length of sternite 6 (longitudinal), width of sternite 6 (transversal) and sternum index were evaluated in this paper. There were not any variation between genotypes regarding length of tibia, length of metatarsus, length of 6. sternit, metatarsal and sternum index. On the other hand there were significant variation between genotypes in terms of other 16 characters. It was found that some genotypes have differentiation characters regarding their morphological structure

The effects of hive type and wintering methods on wintering losses in honeybee, A-mellifera L, colonies in Erzurum conditions

WOS: A1997WJ28500002This research was carried out to investigate the effects of hive type and wintering methods on wentering losses in honeybee, A. mellifera L., colonies in wooden and styrofoam hives in Erzurum conditions and to determine suitable wintering model for this region. Wooden hives for the treatment groups of A, B and C and styrofoam hives for the treatment groups of D, E and F were used in this study. The colonies in groups of A and D wintered outdoor, B and E wintered indoor and C and F wintered under a shed. Colonies in group of A and D were taken out of the experiment in second year. The effect of hive type on the average food consumption of colonies during winter was not significant in first year of the experiment, but it was significant (P<0.05) in second year. The effect of wintering method and interaction between hive type and wintering method on the food consumption were not significant. On the other hand, the effect of hive type on the population decreases was highly significant (P<0.01) in the first year of the experiment; but it was significant (P<0.05) in second year. The effect of wintering method on population decreases of colonies was highly significant (P<0.01) in first year: but it was not significant in second year. However, it was found that the effect of interaction between hive type and wintering method on population decrease was not significant. The average food consumptions of colonies in wooden hives were higher than those of colonies in styrofoam hives, which might be due to less population decrease of colonies in wooden hives. As a result, wooden hives should be used for wintering to reduced the colony losses and bee mortality in the surviving colonies in Ezurum conditions. It was found that overwintering colonies outdoor without taking any precaution was not economic. Wintering colonies indoor or under a shed should be prefered to the wintering outdoor to reduce food consumption and bee losses. Temperature fluctuations during winter period increased food consumption of the colonies considerably