Functional characterization of a glutamate/aspartate transporter from the mosquito Aedes aegypti

Glutamate elicits a variety of effects in insects, including inhibitory and excitatory signals at both neuromuscular junctions and brain. Insect glutamatergic neurotransmission has been studied in great depth especially from the standpoint of the receptor-mediated effects, but the molecular mechanisms involved in the termination of the numerous glutamatergic signals have only recently begun to receive attention. In vertebrates, glutamatergic signals are terminated by Na^+/K^+-dependent high-affinity excitatory amino acid transporters (EAAT), which have been cloned and characterized extensively. Cloning and characterization of a few insect homologues have followed, but functional information for these homologues is still limited. Here we report a study conducted on a cloned mosquito EAAT homologue isolated from the vector of the dengue virus, Aedes aegypti. The deduced amino acid sequence of the protein, AeaEAAT, exhibits 40–50% identity with mammalian EAATs, and 45–50% identity to other insect EAATs characterized thus far. It transports l-glutamate as well as l- and d-aspartate with high affinity in the micromolar range, and demonstrates a substrate-elicited anion conductance when heterologously expressed in Xenopus laevis oocytes, as found with mammalian homologues. Analysis of the spatial distribution of the protein demonstrates high expression levels in the adult thorax, which is mostly observed in the thoracic ganglia. Together, the work presented here provides a thorough examination of the role played by glutamate transport in Ae. aegypti

Assessing the cumulative environmental effects of marine renewable energy developments: establishing common ground

Assessing and managing the cumulative impacts of human activities on the environment remains a major challenge to sustainable development. This challenge is highlighted by the worldwide expansion of marine renewable energy developments (MREDs) in areas already subject to multiple activities and climate change. Cumulative effects assessments in theory provide decision makers with adequate information about how the environment will respond to the incremental effects of licensed activities and are a legal requirement in many nations. In practise, however, such assessments are beset by uncertainties resulting in substantial delays during the licensing process that reduce MRED investor confidence and limit progress towards meeting climate change targets. In light of these targets and ambitions to manage the marine environment sustainably, reducing the uncertainty surrounding MRED effects and cumulative effects assessment are timely and vital. This review investigates the origins and evolution of cumulative effects assessment to identify why the multitude of approaches and pertinent research have emerged, and discusses key considerations and challenges relevant to assessing the cumulative effects of MREDs and other activities on ecosystems. The review recommends a shift away from the current reliance on disparate environmental impact assessments and limited strategic environmental assessments, and a move towards establishing a common system of coordinated data and research relative to ecologically meaningful areas, focussed on the needs of decision makers tasked with protecting and conserving marine ecosystems and services

The transporter-like protein inebriated mediates hyperosmotic stimuli through intracellular signaling

We cloned the inebriated homologue MasIne from Manduca sexta and expressed it in Xenopus laevis oocytes. MasIne is homologous to neurotransmitter transporters but no transport was observed with a number of putative substrates. Oocytes expressing MasIne respond to hyperosmotic stimulation by releasing intracellular Ca(2+), as revealed by activation of the endogenous Ca(2+)-activated Cl(-) current. This Ca(2+) release requires the N-terminal 108 amino acid residues of MasIne and occurs via the inositol trisphosphate pathway. Fusion of the N terminus to the rat gamma-aminobutyric acid transporter (rGAT1) also renders rGAT1 responsive to hyperosmotic stimulation. Immunohistochemical analyses show that MasIne and Drosophila Ine have similar tissue distribution patterns, suggesting functional identity. Inebriated is expressed in tissues and cells actively involved in K(+) transport, which suggests that it may have a role in ion transport, particularly of K(+). We propose that stimulation of MasIne releases intracellular Ca(2+) in native tissues, activating Ca(2+)-dependent K(+) channels, and leading to K(+) transport

Damping of bulk excitations over an elongated BEC - the role of radial modes

We report the measurement of Beliaev damping of bulk excitations in cigar shaped Bose Einstein condensates of atomic vapor. By using post selection, excitation line shapes of the total population are compared with those of the undamped excitations. We find that the damping depends on the initial excitation energy of the decaying quasi particle, as well as on the excitation momentum. We model the condensate as an infinite cylinder and calculate the damping rates of the different radial modes. The derived damping rates are in good agreement with the experimentally measured ones. The damping rates strongly depend on the destructive interference between pathways for damping, due to the quantum many-body nature of both excitation and damping products.Comment: 5 pages, 4 figure

Understanding past population dynamics: Bayesian coalescent-based modeling with covariates

Effective population size characterizes the genetic variability in a population and is a parameter of paramount importance in population genetics. Kingman's coalescent process enables inference of past population dynamics directly from molecular sequence data, and researchers have developed a number of flexible coalescent-based models for Bayesian nonparametric estimation of the effective population size as a function of time. A major goal of demographic reconstruction is understanding the association between the effective population size and potential explanatory factors. Building upon Bayesian nonparametric coalescent-based approaches, we introduce a flexible framework that incorporates time-varying covariates through Gaussian Markov random fields. To approximate the posterior distribution, we adapt efficient Markov chain Monte Carlo algorithms designed for highly structured Gaussian models. Incorporating covariates into the demographic inference framework enables the modeling of associations between the effective population size and covariates while accounting for uncertainty in population histories. Furthermore, it can lead to more precise estimates of population dynamics. We apply our model to four examples. We reconstruct the demographic history of raccoon rabies in North America and find a significant association with the spatiotemporal spread of the outbreak. Next, we examine the effective population size trajectory of the DENV-4 virus in Puerto Rico along with viral isolate count data and find similar cyclic patterns. We compare the population history of the HIV-1 CRF02_AG clade in Cameroon with HIV incidence and prevalence data and find that the effective population size is more reflective of incidence rate. Finally, we explore the hypothesis that the population dynamics of musk ox during the Late Quaternary period were related to climate change

Hybrid Superconductor-Quantum Point Contact Devices using InSb Nanowires

Proposals for studying topological superconductivity and Majorana bound states in nanowires proximity coupled to superconductors require that transport in the nanowire is ballistic. Previous work on hybrid nanowire-superconductor systems has shown evidence for Majorana bound states, but these experiments were also marked by disorder, which disrupts ballistic transport. In this letter, we demonstrate ballistic transport in InSb nanowires interfaced directly with superconducting Al by observing quantized conductance at zero-magnetic field. Additionally, we demonstrate that the nanowire is proximity coupled to the superconducting contacts by observing Andreev reflection. These results are important steps for robustly establishing topological superconductivity in InSb nanowires

Confusion, gaps, and overlaps: A consumer perspective on alternative dispute resolution between consumers and businesses

This report is about the help available to consumers who have experienced a problem with a business that they have been unable to resolve on their own. Some of these problems end up in the small claims courts, but increasingly consumers can turn to Alternative Dispute Resolution (ADR) schemes. This report is about the UK’s current approach to ADR

The experience of adolescent inpatient care and the anticipated transition to the community: Young people’s perspectives

This study explored adolescents' perspectives of inpatient mental health care, focussing on aspects of the inpatient environment they anticipated would help or hinder their transition back home. Semi-structured interviews were conducted with 12 adolescent inpatients; transcripts were analysed thematically. Participants experienced inpatient treatment as offering a mix of benefits (e.g., supportive relationships) and drawbacks (e.g., living in a “fake world”). They anticipated the transition home as providing opportunities for personal growth and consolidation of new coping skills, but also posing challenges concerning re-entering the “real world” after the experience of being “wrapped in cotton wool”. Self-determination theory and attachment theory offer two potential frameworks for understanding these opportunities and challenges. Inpatient care has the potential to foster key mechanisms for adaptive development, creating a platform for developing positive future behaviours. Community teams should work closely with inpatient units to support the generalisation of the young person's newly acquired coping skills

Unique Mass Texture for Quarks and Leptons

Texture specific quark mass matrices which are hermitian and hierarchical are examined in detail . In the case of texture 6 zeros matrices, out of sixteen possibilities examined by us, none is able to fit the low energy data (LED), for example, $V_{us} = 0.2196 \pm 0.0023$, $V_{cb} = 0.0395 \pm 0.0017$, $\frac{V_{ub}}{V_{cb}} = 0.08 \pm 0.02$, $V_{td}$ lies in the range $0.004 - 0.013$ (PDG). Similarly none of the 32 texture 5 zeros mass matrices considered is able to reproduce LED. In particular, the latest data from LEP regarding $|V_{ub}|/|V_{cb}|(=0.093\pm0.016)$ rules out all of them. In the texture 4 zeros case, we find that there is a unique texture structure for $U$ and $D$ mass matrices which is able to fit the data.Comment: 12 pages, LaTeX,some changes in the references,minor changes in the text,to appear in Phys Rev D(Rapid communications

Breast diseases in males--a morphological review of 150 cases

Objective: This study was carried out to observe the prevalence breast diseases of males in our setup. Method: All cases of male breast disease diagnosed from 1991-97. Results: One hundred and fifty (150) cases of male breast diseases were diagnosed. Age of the patients ranged from 4 to 90 years, with mean age 38.75 years (median = 33 years). Gynecomastia was the most common pathological abnormality of the male breast (58.66%). Most of the patients presented in the 3rd decade of life. Amongst the malignant conditions, infiltrating ductal carcinoma was most prevalent (82%). Most of the patients with malignancy presented in the 5th and 6th decades of life. Conclusion: Gynecomastia was the most prevalent male breast disorder, followed by infiltrating ductal carcinoma. Our findings correspond with that of world literature