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Aquatic insects typically dominate the ecology of freshwater ecosystems while relatively few species are found in saline waters. As human activities are changing the salinity regimes of freshwater ecosystems—typically by making them more saline, ecologists are reporting declines in insect diversity. These observations imply that insect physiological systems play a major role in how species respond to salinity change. This review provides a general overview of insect ormoregulatory physiology and highlights recent advances in the field.

Human obesity is a complex metabolic disorder disproportionately affecting people of lower socioeconomic strata, and ethnic minorities, especially African Americans and Hispanics. Although genetic predisposition and a positive energy balance are implicated in obesity, these factors alone do not account for the excess prevalence of obesity in lower socioeconomic populations. Therefore, environmental factors, including exposure to pesticides, heavy metals, and other contaminants, are agents widely suspected to have obesogenic activity, and they also are spatially correlated with lower socioeconomic status. Our study investigates the causal relationship between exposure to the heavy metal, cadmium (Cd), and obesity in a cohort of children and in a zebrafish model of adipogenesis. An extensive collection of first trimester maternal blood samples obtained as part of the Newborn Epigenetics Study (NEST) was analyzed for the presence of Cd, and these results were cross analyzed with the weight-gain trajectory of the children through age 5 years. Next, the role of Cd as a potential obesogen was analyzed in an in vivo zebrafish model. Our analysis indicates that the presence of Cd in maternal blood during pregnancy is associated with increased risk of juvenile obesity in the offspring, independent of other variables, including lead (Pb) and smoking status. Our results are recapitulated in a zebrafish model, in which exposure to Cd at levels approximating those observed in the NEST study is associated with increased adiposity. Our findings identify Cd as a potential human obesogen. Moreover, these observations are recapitulated in a zebrafish model, suggesting that the underlying mechanisms may be evolutionarily conserved, and that zebrafish may be a valuable model for uncovering pathways leading to Cd-mediated obesity in human populations.

Abigail Buchwalter recounts what happened to the nuclei of cells lacking all lamin genes.

This paper examines how the intercultural conception of human rights, fueled by the modes of reciprocal recognition associated with Hegel’s social philosophy, draws on traditional understandings of human dignity while avoiding the essentialism associated with those understandings. Part 1 summarizes core elements of an intercultural theory of human rights while addressing the general question of how that theory accommodates an understanding of the relationship of human dignity and human rights. Part 2 presents the intercultural approach as committed to a view of human dignity focused on the intrinsic worthof individuals, but understood, not—with Kant—as an anthropologically inherent property, but as one forged in relations of intersubjective recognition. Part 3, critically engaging arguments of C Beitz and J Habermas, claims that an intercultural approach entails a status-basedconception of human dignity, one that construes the latter, not as a metaphysically conceived inherent quality, but as a function of membership in a social order supportive of both liberal right claims and a republican commitment to rights systems generally. Drawing on the work of Hegel and critically engaging the position of A Sangiovanni, Part 4 construes human dignity in terms of a doctrine of human rights expressive of a common humanity, one understood, however, not as an essential attribute of human beings, but in terms of a globally realized legal-political order whose members are dispositionally committed to the worth of all members of the human community and the value of human community itself. Critically appropriating the work of H Arendt for the intercultural theory, Part 5 considers the centrality of actual politicsto a dignitarian account of human rights. Part 6 construes human dignity, again with Kant, in terms of the principle of autonomy, but one understood, not abstractly, but—engaging Pico della Mirandola—as the fallibilistically conceived process of social learning on the part the members of the human community. Part 7 considers how the intercultural view, with the idea of social practiceexpressive of collective human agency, accommodates a concept of human dignity understood as the “foundation”—nuanced and variegated—of human rights. Part 8 details the specific normativityof an intercultural conception, asserting that despite and even because of its attention to the empirical realities of social, historical, and political life, that conception remains committed, as with essentialist views, to context-transcending norms capable of calling into question actual practices and policies. Here, recourse is had to a concept of recognition understood both as a principle of evaluation and as a social practice encompassing the activity of individuals and groups engaged in the discourse on human rights.

•Temperature, salinity and O2are fundamental factors driving aquatic insect assemblages.•Here we review their sensitivity to combined effects of these three factors.•Given concurrent effects on energy budgets, one stressor may amplify the effect of another.•Sensitivity of insects to these three stressors may be influenced by their mode of respiration.•Consequently, insect assemblages may respond similarly to the different stressors.

Non-centrosomal microtubule-organizing centres (ncMTOCs) have a variety of roles that are presumed to serve the diverse functions of the range of cell types in which they are found. ncMTOCs are diverse in their composition, subcellular localization and function. Here we report a perinuclear MTOC in Drosophilafat body cells that is anchored by the Nesprin homologue Msp300 at the cytoplasmic surface of the nucleus. Msp300 recruits the microtubule minus-end protein Patronin, a calmodulin-regulated spectrin-associated protein (CAMSAP) homologue, which functions redundantly with Ninein to further recruit the microtubule polymerase Msps—a member of the XMAP215 family—to assemble non-centrosomal microtubules and does so independently of the widespread microtubule nucleation factor γ-Tubulin. Functionally, the fat body ncMTOC and the radial microtubule arrays that it organizes are essential for nuclear positioning and for secretion of basement membrane components via retrograde dynein-dependent endosomal trafficking that restricts plasma membrane growth. Together, this study identifies a perinuclear ncMTOC with unique architecture that regulates microtubules, serving vital functions.

Within a cell, proteins have distinct and highly variable half-lives. As a result, the molecular ages of proteins can range from seconds to years. How the age of a protein influences its environmental interactions is a largely unexplored area of biology. To investigate the age-selectivity of cellular pathways, we developed a methodology termed “proteome birthdating” that barcodes proteins based on their time of synthesis. We demonstrate that this approach provides accurate measurements of protein turnover kinetics from a single biological sample encoding multiple labeling time-points. As a first application of the birthdated proteome, we investigated the age distribution of the human ubiquitinome. Our results indicate that the vast majority of ubiquitinated proteins in a cell consist of newly synthesized proteins and that these young proteins constitute the bulk of the degradative flux through the proteasome. Rapidly ubiquitinated nascent proteins are enriched in cytosolic subunits of large protein complexes. Conversely, proteins destined for the secretory pathway and vesicular transport have older ubiquitinated populations. Our data also identify a smaller subset of older ubiquitinated cellular proteins that do not appear to be targeted to the proteasome for rapid degradation. Together, our data provide an age census of the human ubiquitinome and establish proteome birthdating as a robust methodology for investigating the protein age-selectivity of diverse cellular pathways.

The genome is packaged and organized nonrandomly within the 3D space of the nucleus to promote efficient gene expression and to faithfully maintain silencing of heterochromatin. The genome is enclosed within the nucleus by the nuclear envelope membrane, which contains a set of proteins that actively participate in chromatin organization and gene regulation. Technological advances are providing views of genome organization at unprecedented resolution and are beginning to reveal the ways that cells co-opt the structures of the nuclear periphery for nuclear organization and gene regulation. These genome regulatory roles of proteins of the nuclear periphery have important influences on development, disease and ageing.

All freshwater organisms are challenged to control their internal balance of water and ions in strongly hypotonic environments. We compared the influence of external salinity on the oxygen consumption rates (ṀO2) of three species of freshwater insects, one snail and two crustaceans. Consistent with available literature, we found a clear decrease in ṀO2 with increasing salinity in the snail Elimia sp. and crustaceans Hyalella azteca and Gammarus pulex (r5=−0.90, P=0.03). However, we show here for the first time that metabolic rate was unchanged by salinity in the aquatic insects, whereas ion transport rates were positively correlated with higher salinities. In contrast, when we examined the ionic influx rates in the freshwater snail and crustaceans, we found that Ca uptake rates were highest under the most dilute conditions, while Na uptake rates increased with salinity. In G. pulex exposed to a serially diluted ion matrix, Ca uptake rates were positively associated with ṀO2 (r5=−0.93, P=0.02). This positive association between Ca uptake rate and ṀO2 was also observed when conductivity was held constant but Ca concentration was manipulated (1.7–17.3 mg Ca l−1) (r5=0.94, P=0.05). This finding potentially implicates the cost of calcium uptake as a driver of increased metabolic rate under dilute conditions in organisms with calcified exoskeletons and suggests major phyletic differences in osmoregulatory physiology. Freshwater insects may be energetically challenged by higher salinities, while lower salinities may be more challenging for other freshwater taxa.

The fields of behavioral ecology, conservation science, and environmental toxicology individually aim to protect and manage the conservation of wildlife in response to anthropogenic stressors, including widespread anthropogenic pollution. Although great emphasis in the field of toxicology has been placed on understanding how single pollutants affect survival, a comprehensive, interdisciplinary approach that includes behavioral ecology is essential to address how anthropogenic compounds are a risk for the survival of species and populations in an increasingly polluted world. We provide an integrative framework for behavioral ecotoxicology using Tinbergen's four postulates (causation and mechanism, development and ontogeny, function and fitness, and evolutionary history and phylogenetic patterns). The aims of this review are: 1) to promote an integrative view and re-define the field of integrative behavioral ecotoxicology; 2) to demonstrate how studying ecotoxicology can promote behavior research; and 3) to identify areas of behavioral ecotoxicology that require further attention to promote the integration and growth of the field.

At dry and clean material junctions of rigid materials the corrugation of the sliding energy landscape is dominated by variations of Pauli repulsions. These occur when electron clouds centered around atoms in adjacent layers overlap as they slide across each other. In such cases there exists a direct relation between interfacial surface (in)commensurability and superlubricity, a frictionless and wearless tribological state. The Registry Index is a purely geometrical parameter that quantifies the degree of interlayer commensurability, thus providing a simple and intuitive method for the prediction of sliding energy landscapes at rigid material interfaces. In the present study, we extend the applicability of the Registry Index to nonparallel surfaces, using a model system of nanotube motion on flat hexagonal materials. Our method successfully reproduces sliding energy landscapes of carbon nanotubes on graphene calculated using a Lennard-Jones-type and the Kolmogorov–Crespi interlayer potentials. Furthermore, it captures the sliding energy corrugation of a boron nitride nanotube on hexagonal boron nitride calculated using a recently developed interlayer potential for hexagonal boron nitride (h-BN). Finally, we use the Registry Index to predict the sliding energy landscapes of the heterogeneous junctions of a carbon nanotubes on h-BN and of boron nitride nanotubes on graphene that are shown to exhibit a significantly reduced corrugation. For such rigid interfaces this is expected to be manifested by superlubric motion.

Over the past 18 months, recurrent activating mutations within the oestrogen receptor α (ER) LBD have been detected in 15–20% of patients with metastatic ER-positive endocrine-resistant breast cancerThe ER LBD mutations confer constitutive ligand-independent activity and are relatively resistant to tamoxifen and fulvestrant treatmentThese mutations in the gene encoding the ER, ESR1, are detected mainly in metastatic tumours, implicating the clonal selection of these mutations as the mechanism of resistance to therapyStructural studies have shown that the ER LBD mutations lead to ligand-independent stabilization of the LBD in the agonistic conformationTo study the clonal evolution and discern the full genetic complexity and clinical significance of the ESR1mutations, new sensitive sequencing technologies will need to be appliedPotential strategies to overcome ER-related endocrine resistance include high-dose fulvestrant and tamoxifen, inhibitors of ER co-activator proteins, novel SERDs and SERMs, and other agents targeting the ER signalling axis

Nup50 is a mobile nucleoporin with a pronounced presence both at the nuclear pore complex and in the nucleoplasm that can move between these different localizations. The dynamic behavior of Nup50 in both locations is dependent on active transcription by RNA polymerase II.

With wireless communications becoming an important technology and growth engine for the semiconductor industry, many semiconductor companies are developing technologies to differentiate themselves in this area. One means of accomplishing this goal is to find a way to integrate passive components, which currently make up more than 70 of the discrete components in a wireless handset, directly on-chip thereby greatly simplifying handsets. While a number of technologies are being investigated to allow on-chip integration, microelectromechanical systems technologies are an important part of this development effort. They have been used to create switches, filters, local oscillators, variable capacitors, and high-quality inductors, to name a few examples. The lithography requirements for these devices are very different than those found in standard semiconductor fabrication with the most important involving patterning over extreme topography. We discuss some of the fabrication challenges for these devices as well as some approaches that have been demonstrated to satisfy them. © 2003 Society of Photo-Optical Instrumentation Engineers.

Abstract: Many companies and purchasing departments only possess a limited knowledge about the modelling of inter-company business processes for electronic procurement. In the past the discussion about electronic procurement was mostly focused on technical aspects. This article introduces a reference process model for procurement auctions. The process model is made up of a basic process, which describes a minimal process for procurement auctions, and a number of process alternatives, which allow for the adoption of the basic process to changing parameters and individual company requirements.

Abstract: Electrically conducting adhesive materials are promising alternatives for lead (Pb)-containing solders in microelectronic applications. However, most common silver-filled epoxy materials have various limitations to meet the requirements of the solder joints yet. To overcome these limitations, several new formulations have been developed recently. Among them, a new high conductivity Pb-free, conducting adhesive developed for low temperature applications has been previously reported. This conducting adhesive contains a conducting copper filler powder coated with a low melting point metal or alloy, such as Sn or BiSn alloys. The low melting point layer serves as a joining material among the filler particles as well as to the substrate. In this paper, characterization of electroplated BiSn alloys on a Cu substrate is reported for their microstructure, electrical properties, oxidation behavior, and others. The experimental results have provided a better understanding of the joining mechanism of the newly developed Pb-free conductive adhesive materials.

AbstractThere is a difference between technologically-important adhesion or practical adhesion, and fundamental or basic adhesion. What is important in the understanding of fundamental adhesion may be of insignificant interest to technology. A manufacturer is interested in how to improve the reliability of the structure being built should an interface problem exist, rather than knowing the precise value of the fundamental adhesion. It is not possible to measure fundamental adhesion for technologically-important structures due to the inability to account for all energy dissipating processes during the test. Adhesion measurements are plagued with the mode of interface loading issue: the resemblance of test interface loading to that of the actual manufactured part. What technology needs is a simple adhesion test method that is practical for product development, giving reliable information about the interface integrity. The present paper compares the value of two adhesion tests for microelectronics applications and emphasizes the importance of locus of failure analyses. A realignment of structure reliability modeling is suggested by the usage of effective fundamental adhesion instead of the standard undeterminable fundamental adhesion.

Five different fluorinated polyimides were characterized using X-ray photoelectron spectroscopy (XPS). Elemental compositions and polyimide stoichiometries as elucidated with XPS are reported. The fluorinated polyimides derived from corresponding poly(amic acid)s were completely imidized after thermal cure at 350°C, giving rise to a single N 1s peak at 400.8 eV. Interestingly, fluorine segregation on the cured polyimide surface was found to be a function of the polyimide backbone stiffness.