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Improved reference genome of Aedes aegypti informs arbovirus vector control
Get PDFFemale Aedes aegypti mosquitoes infect more than 400 million people each year with dangerous viral pathogens including dengue, yellow fever, Zika and chikungunya. Progress in understanding the biology of mosquitoes and developing the tools to fight them has been slowed by the lack of a high-quality genome assembly. Here we combine diverse technologies to produce the markedly improved, fully re-annotated AaegL5 genome assembly, and demonstrate how it accelerates mosquito science. We anchored physical and cytogenetic maps, doubled the number of known chemosensory ionotropic receptors that guide mosquitoes to human hosts and egg-laying sites, provided further insight into the size and composition of the sex-determining M locus, and revealed copy-number variation among glutathione S-transferase genes that are important for insecticide resistance. Using high-resolution quantitative trait locus and population genomic analyses, we mapped new candidates for dengue vector competence and insecticide resistance. AaegL5 will catalyse new biological insights and intervention strategies to fight this deadly disease vector
Interspecific studies of circadian genes period and timeless in Drosophila
No full textThe level of rescue of clock function in genetically arrhythmic Drosophila melanogaster hosts using interspecific clock gene transformation was used to study the putative intermolecular coevolution between interacting clock proteins. Among them PER and TIM are the two important negative regulators of the circadian clock feedback loop. We transformed either the D. pseudoobscura per or tim transgenes into the corresponding arrhythmic D. melanogaster mutant (per01 or tim01) and observed >50% rhythmicity but the period of activity rhythm was either longer (D. pseudoobscura-per) or shorter than 24 h (D. pseudoobscura-tim) compared to controls. By introducing both transgenes simultaneously into double mutants, we observed that the period of the activity rhythm was rescued by the pair of hemizygous transgenes (~24 h). These flies also showed a more optimal level of temperature compensation for the period. Under LD 12:12 these flies have a D. pseudoobscura like activity profile with the absence of morning anticipation as well as a very prominent earlier evening peak of activity rhythm. These observation are consistent with the view that TIM and PER form a heterospecific coevolved module at least for the circadian period of activity rhythms. However the strength of rhythmicity was reduced by having both transgenes present, so while evidence for a coevolution between PER and TIM is observed for some characters it is not for others
Progress toward Understanding Protein S-acylation: Prospective in Plants
Get PDFS-acylation, also known as S-palmitoylation or palmitoylation, is a reversible posttranslational lipid modification in which long chain fatty acid, usually the 16-carbon palmitate, covalently attaches to a cysteine residue(s) throughout the protein via a thioester bond. It is involved in an array of important biological processes during growth and development, reproduction and stress responses in plant. S-acylation is a ubiquitous mechanism in eukaryotes catalyzed by a family of enzymes called Protein S-Acyl Transferases (PATs). Since the discovery of the first PAT in yeast in 2002 research in S-acylation has accelerated in the mammalian system and followed by in plant. However, it is still a difficult field to study due to the large number of PATs and even larger number of putative S-acylated substrate proteins they modify in each genome. This is coupled with drawbacks in the techniques used to study S-acylation, leading to the slower progress in this field compared to protein phosphorylation, for example. In this review we will summarize the discoveries made so far based on knowledge learnt from the characterization of protein S-acyltransferases and the S-acylated proteins, the interaction mechanisms between PAT and its specific substrate protein(s) in yeast and mammals. Research in protein S-acylation and PATs in plants will also be covered although this area is currently less well studied in yeast and mammalian systems
Star formation in IRDC G31.97+0.07
Get PDFWe utilize multiple-waveband continuum and molecular-line data of CO isotopes to study the dynamical structure and physical properties of the IRDC G31.97+0.07. We derive the dust temperature and H2 column density maps of the whole structure by spectral energy distribution fitting. The total mass is about 2.5×105M⊙ for the whole filamentary structure and about 7.8×104M⊙ for the infrared dark cloud (IRDC). Column density probability distribution functions (PDFs) produced from the column density map are generally in the power-law form, suggesting that this part is mainly gravity dominant. The flatter slope of the PDF of the IRDC implies that it might be compressed by an adjacent, larger H II region. There are 27 clumps identified from the 850 μm continuum located in this filamentary structure. Based on the average spacing of the fragments in the IRDC, we estimate the age of the IRDC. The age is about 6.4 Myr, assuming inclination angle i = 30°. For 18 clumps with relatively strong CO and 13CO (3–2) emission, we study their line profiles and stabilities. We find five clumps with blue profiles that indicate gas infall motion and two clumps with red profiles that indicate outflows or expansion. Only one clump has αvir > 2, suggesting that most clumps are gravitationally bound and tend to collapse. In the mass–Req diagram, 23 of 27 clumps are above the threshold for high-mass star formation, suggesting that this region can be a good place for studying high-mass star forming
The NOS3 G894T (rs1799983) and-786T/C (rs2070744) polymorphisms are associated with elite swimmer status
Get PDFEndothelial nitric oxide synthase (NOS3) generates nitric oxide in blood vessels and is involved in the regulation of vascular function, metabolism and muscle fibre type transformations. Evidence suggests that the NOS3 G894T (rs1799983) and -786T/C (rs2070744) polymorphisms are associated with athletic performance. The purpose of this study was to determine the association between the NOS3 G894T and -786T/C polymorphisms with elite swimmer status in Polish athletes. One hundred and ninety-seven Polish swimmers (104 males and 93 females), who competed in national and international events, and 379 healthy control subjects (222 males and 157 females) were recruited for this study. The swimmers were divided into two groups: short distance swimmers (SDS; n=147; 50-200 m) and long distance swimmers (LDS; n=49; more than 500 m). As expected, the frequencies of the -786T/C T allele (77.0 vs. 63.1%, p = 0.0085) and G-T haplotype (63.7 vs. 52.0, p=0.025) were significantly higher in the LDS group in comparison with controls. Compared with the -786T/C CC genotype, the chance of being a long distance swimmer was 8.49 times higher (CI=1.14-62.78, p=0.023) for the carriers of -786T/C T allele than in control subjects. On the other hand, the Asp allele frequency was significantly higher in the female SDS group compared with controls (34.3 vs. 18.5%, p=0.00043). In conclusion, our results demonstrate that the T allele and the G-T haplotype of the -786T/C and G894T polymorphisms may be beneficial for long distance swimmers
The Tangibility of Personalized 3D-Printed Feedback May Enhance Youths' Physical Activity Awareness, Goal Setting, and Motivation: Intervention Study
Get PDFBackground: In the United Kingdom, most youth fail to achieve the government guideline of 60 min of moderate to vigorous physical activity (MVPA) daily. Reasons that are frequently cited for the underachievement of this guideline include (1) a lack of awareness of personal physical activity levels (PALs) and (2) a lack of understanding of what activities and different intensities contribute to daily targets of physical activity (PA). Technological advances have enabled novel ways of representing PA data through personalized tangible three-dimensional (3D) models. Objective: The purpose of this study was to investigate the efficacy of 3D-printed models to enhance youth awareness and understanding of and motivation to engage in PA.
Methods: A total of 39 primary school children (22 boys; mean age 7.9 [SD 0.3] years) and 58 secondary school adolescents (37 boys; mean age 13.8 [SD 0.3] years) participated in a 7-week fading intervention, whereby participants were given 3D-printed models of their previous week’s objectively assessed PALs at 4 time points. Following the receipt of their 3D model, each participant completed a short semistructured video interview (children, 4.5 [SD 1.2] min; adolescents, 2.2 [SD 0.6] min) to assess their PA awareness, understanding, and motivation. Data were transcribed verbatim and thematically analyzed to enable key emergent themes to be further explored and identified.
Results: Analyses revealed that the 3D models enhanced the youths’ awareness of and ability to recall and self-evaluate their PA behaviors. By the end of the study, the youths, irrespective of age, were able to correctly identify and relate to the government’s PA guideline represented on the models, despite their inability to articulate the government's guideline through time and intensity. Following the fourth 3D model, 72% (71/97) of the youths used the models as a goal-setting strategy, further highlighting such models as a motivational tool to promote PA.Conclusions: The results suggest that 3D-printed models of PA enhanced the youths’ awareness of their PA levels and provided a motivational tool for goal setting, potentially offering a unique strategy for future PA promotion
Wild and laboratory exposure to cues of predation risk increases relative brain mass in male guppies
Get PDFThere is considerable diversity in brain size within and among species, and substantial dispute over the causes, consequences and importance of this variation. Comparative and developmental studies are essential in addressing this controversy.
Predation pressure has been proposed as a major force shaping brain, behaviour and life history. The Trinidadian guppy, Poecilia reticulata, shows dramatic variation in predation pressure across populations. We compared the brain mass of guppies from high and low predation populations collected in the wild. Male but not female guppies exposed to high predation possessed heavier brains for their body size compared to fish from low predation populations.
The brain is a plastic organ, so it is possible that the population differences we observed were partly due to developmental responses rather than evolved differences. In a follow‐up study, we raised guppies under cues of predation risk or in a control condition. Male guppies exposed to predator cues early in life had heavier brains relative to their body size than control males, while females showed no significant effect of treatment.
Collectively our results suggest that male guppies exposed to predation invest more in neural tissue, and that these differences are at least partly driven by plastic responses
HRD Programs in the United Kingdom
Get PDFThe Problem. Very little research has examined the current state of human resource development (HRD) education in the United Kingdom, or the factors influencing its genesis and development. The Solution. We analyze historical and contemporary factors influencing HRD education in the United Kingdom, identify different levels and providers of HRD qualifications, and outline curriculum content of HRD programs. Our aim is to clarify the current situation, by proposing a tripartite model of stakeholders in HRD education based on the United Kingdom but which might assist in the analysis of HRD education in other geographic areas. The Stakeholders. HRD education in the United Kingdom is largely influenced by three key stakeholders: the U.K. government, the Chartered Institute of Personnel and Development (the professional body for human resources), and the academy. Our analysis reveals complex and dynamic interactions between these stakeholders, which have implications for them as well as learners, practitioners, and researchers. © The Author(s) 2015
The Offline Group Seat Reservation Knapsack Problem with Profit on Seats
Get PDFIn this paper we present the Group Seat Reservation Knapsack Problem with Profit on Seat. This is an extension of the the Offline Group Seat Reservation Knapsack Problem. In this extension we introduce a profit evaluation dependant on not only the space occupied, but also on the individual profit brought by each reserved seat. An application of the new features introduced in the proposed extension is to influence the distribution of passengers, such as assigning seats near the carriage centre for long journeys, and close to the door for short journeys. Such distribution helps to reduce the excess of dwelling time on platform. We introduce a new GRASP based algorithm that solves the original problem and the newly proposed one. In the experimental section we show that such algorithm can be useful to provide a good feasible solution very rapidly, a desirable condition in many real world systems. Another application could be to use the algorithm solution as a startup for a successive branch and bound procedure when optimality is desired. We also add a new class of problem with five test instances that represent some challenging real-world scenarios that have not been considered before. Finally, we evaluate both the existing model, the newly proposed model, and analyse the pros and cons of the proposed algorithm
Synthesis and photophysical properties of meso-aminophenyl-substituted heptamethine dyes as potential leads to new contrast agents
Get PDFThe series of rigid meso-aminophenyl-substituted heptamethine dyes presented herein exhibit surprising fluorescence properties, demonstrating larger Stokes shifts when compared with both structurally similar rigid meso-chlorophenyl and linear heptamethine dyes. Based on their photophysical properties, these are of considerable importance to the development of contrast agents, within biology and medicine. © 2019 The Authors. Coloration Technology © 2019 Society of Dyers and Colourist
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