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Three-dimensional structures of SARS-CoV-2 and other coronaviral proteins archived in the Protein Data Bank were used to analyze viral proteome evolution during the first six months of the COVID-19 pandemic. Analyses of spatial locations, chemical properties, and structural and energetic impacts of the observed amino acid changes in >48,000 viral proteome sequences showed how each one of the 29 viral study proteins have undergone amino acid changes. Structural models computed for every unique sequence variant revealed that most substitutions map to protein surfaces and boundary layers with a minority affecting hydrophobic cores. Conservative changes were observed more frequently in cores versus boundary layers/surfaces. Active sites and protein-protein interfaces showed modest numbers of substitutions. Energetics calculations showed that the impact of substitutions on the thermodynamic stability of the proteome follows a universal bi-Gaussian distribution. Detailed results are presented for six drug discovery targets and four structural proteins comprising the virion, highlighting substitutions with the potential to impact protein structure, enzyme activity, and functional interfaces. Characterizing the evolution of the virus in three dimensions provides testable insights into viral protein function and should aid in structure-based drug discovery efforts as well as the prospective identification of amino acid substitutions with potential for drug resistance.

Piezo1 is abona fidemechanosensitive ion channel ubiquitously expressed in mammalian cells. The distribution of Piezo1 within a cell is essential for various biological processes including cytokinesis, cell migration, and wound healing. However, the underlying principles that guide the subcellular distribution of Piezo1 remain largely unexplored. Here, we demonstrate that membrane curvature serves as a key regulator of the spatial distribution of Piezo1 in the plasma membrane of living cells. Piezo1 depletes from highly curved membrane protrusions such as filopodia and enriches to nanoscale membrane invaginations. Quantification of the curvaturedependent sorting of Piezo1 directly reveals thein situnano-geometry of the Piezo1-membrane complex. Piezo1 density on filopodia increases upon activation, independent of Ca2+, suggesting flattening of the channel upon opening. Consequently, the expression of Piezo1 inhibits filopodia formation, an effect that diminishes with channel activation.

Compared with age-matched employees, university students report higher levels of chronic stress and this may affect their decision-making. The impact of chronic stress and physiological reactivity upon cognitive function is receiving more attention, but few studies have empirically assessed the associations of these variables concurrently. Our aim was to investigate if chronic student stress, as assessed by effort-reward imbalance (ERI) and overcommitment, and physiological reactivity, were related to decision-making. As measures of physiological reactivity, we collected salivary alpha-amylase (sAA) and continuously recorded heart rate variability (HRV) data from male students (

The Pan-Eurasian Experiment (PEEX) program was initiated as a bottom-up approach by the researchers coming from Finland and Russia in October 2012. The PEEX China kick off meeting was held in November 2013. During its five years in operation, the program has established a governance structure and delivered a science plan for the Northern Eurasian region. PEEX has also introduced a concept design for a modelling platform and ground-based in situ observation systems for detecting land-atmosphere and ocean-atmosphere interactions. Today, PEEX has an extensive researcher’s network representing research communities coming from the Nordic countries, Russia and China. PEEX is currently carrying out its research activities on a project basis, but is looking for more coordinated funding bases, especially in Russia and in China. The near-future challenge in implementing the PEEX research agenda is to achieve a successful integration and identification of the methodological approaches of the socio-economic research to environmental sciences. Here we give insight into these issues and provide an overview on the main tasks for the upcoming years. The Pan-Eurasian Experiment (PEEX) program was initiated as a bottom-up approach by the researchers coming from Finland and Russia in October 2012. The PEEX China kick off meeting was held in November 2013. During its five years in operation, the program has established a governance structure and delivered a science plan for the Northern Eurasian region. PEEX has also introduced a concept design for a modelling platform and ground-based in situ observation systems for detecting land-atmosphere and ocean-atmosphere interactions. Today, PEEX has an extensive researcher’s network representing research communities coming from the Nordic countries, Russia and China. PEEX is currently carrying out its research activities on a project basis, but is looking for more coordinated funding bases, especially in Russia and in China. The near-future challenge in implementing the PEEX research agenda is to achieve a successful integration and identification of the methodological approaches of the socio-economic research to environmental sciences. Here we give insight into these issues and provide an overview on the main tasks for the upcoming years. The Pan-Eurasian Experiment (PEEX) program was initiated as a bottom-up approach by the researchers coming from Finland and Russia in October 2012. The PEEX China kick off meeting was held in November 2013. During its five years in operation, the program has established a governance structure and delivered a science plan for the Northern Eurasian region. PEEX has also introduced a concept design for a modelling platform and ground-based in situ observation systems for detecting land-atmosphere and ocean-atmosphere interactions. Today, PEEX has an extensive researcher’s network representing research communities coming from the Nordic countries, Russia and China. PEEX is currently carrying out its research activities on a project basis, but is looking for more coordinated funding bases, especially in Russia and in China. The near-future challenge in implementing the PEEX research agenda is to achieve a successful integration and identification of the methodological approaches of the socio-economic research to environmental sciences. Here we give insight into these issues and provide an overview on the main tasks for the upcoming years.

Policy emphasis on financial-sector development has shifted away from microfinance and towards the development of ‘inclusive financial markets’. But, for inclusion to take place, policy must address barriers to access. This article analyses the socio-economic, demographic and geographical factors associated with financial-service use across formal, semi-formal and informal financial services in Kenya between 2006 and 2009, including the new and rapidly growing mobile-phone-based payments service – M-PESA. It finds that, despite an expansion of services, evidence of access barriers is now clearer than it was in 2006. However, there is some evidence that M-PESA is reversing age as a barrier to inclusion, but, as yet, it is more of a complement than a substitute for formal services.

Benade’s book, born as a thesis and then developed into a text, is full of insight and detail (it includes 20 pages of references). The New Zealand Curriculum (2007) is treated to an outing as a le...

Researchers have hypothesized that races with high levels of melanin may possess superior cochlear robusticity. This study aimed to examine the relationship between cochlear function and racial heritage, by determining if a significant difference existed in otoacoustic emission (OAE) characteristics and hearing sensitivity between differing groups. OAEs, puretone thresholds, and tympanometric measures were obtained from 18 Caucasians and 19 Africans. Seven albino Caucasians, a group with defective melanin production/distribution, were included for comparative purposes. An analysis of variance with repeated measures was applied to the data, to establish the group interactions of significance. Africans were found to display significantly stronger OAEs than Caucasians. However, the OAEs of albino Caucasians did not significantly differ from those of the other groups. Results did show significantly poorer hearing thresholds for the albino Caucasian group than for the Caucasians. These findings suggest...

This paper examines existing measures taken to protect the coastal zones of the Mediterranean Sea and assesses their success. A summary of the main pressures facing this region is given, followed by an analysis of the legislation covering coastal zone development in ten countries: Algeria, Croatia, Egypt, France, Israel, Italy, Malta, Spain, Tunisia and Turkey. The paper finds that not all of these States have legislation specifically covering coastal zones, but there is concern in all areas that existing legislation is not working. The costs and benefits of controlling coastal development are examined. Firstly, a literature review of valuation studies identifies a range of values placed on the developed and undeveloped coastline for both users and local property owners. These values were then used in a model to evaluate policy options to control development of a stretch of coastline. The model indicates that a stricter control regime of coastal development may provide significant benefits.

There is no reported research in the literature of using shape-memory alloy (SMA) actuators for variable area exhaust nozzles for a jet engine, to the authors' best knowledge. SMA actuators have the advantage of a high power-to-weight ratio and can result in dramatic weight reduction as compared to hydraulic systems. However, the difficulty of using SMA actuators for controlling variable area exhaust nozzles lies in the fact that the temperature near the exhaust nozzle is far higher than the transformation temperature of an SMA actuator. Due to the flexibility and small volume of SMA wire actuators, they can be remotely replaced in a region where the temperature is lower than that of its transformation temperature. By exploiting this fact, this paper presents a novel design of a proof-of-concept variable area exhaust nozzle using shape-memory alloy wire actuators. The SMA actuators are remotely placed away from the exhaust nozzle area so that the environmental temperature is below their transformation temperature. By electrically heating the SMA actuators, the exhaust nozzle will experience an area reduction of up to 40%. Bias springs will apply forces to return the exhaust nozzle to the open-up configuration. A feedback controller based sliding-mode method is used to regulate the SMA actuator position. Experimental results demonstrate that the proposed design meets the desired area variation specifications and shows the promise of a lightweight and simple exhaust nozzle design by using shape-memory alloy actuators.

Photoreactive phenylazide-end-capped liquid copolymers were prepared by ring-opening copolymerization of epsilon-caprolactone (CL) and trimethylene carbonate (TMC) at an equimolar monomer feed ratio in the presence of a polyol, namely, a low-molecular-weight alcohol (di-, tri-, and tetraol) or poly(ethylene glycol) (PEG) as an initiator and tin(II) 2-ethylhexanoate as a catalyst, followed subsequently by phenylazide derivatization at their hydroxyl terminus. These tri- and tetrabranched liquid copolymers (precursors) with a molecular weight from approximately 2500 to 7000 g/mol were cross-linked to yield insoluble solids by ultraviolet (UV) light irradiation. The photocuring rate increased with increasing functionality of phenylazide and UV intensity and decreasing thickness of the liquid film of precursors. The photo-cross-linkability of phenylazide-derivatized liquid copolymers was found to be higher than that of the corresponding coumarin-derivatized liquid copolymers. Poly(lactide) (PLA) films surface-layered with photocured copolymers were prepared by coating surfaces with phenylazide-derivatized copolymers and their subsequent photoirradiation. Endothelial cells adhered well on the nontreated PLA and low-molecular-weight alcohol-based copolymer-layered and photocured films. Little cell adhesion was observed on the hydrolytically surface-eroded PLA film and the PEG-based copolymer-layered film. When a phenylazide-derivatized hexapeptide with the cell-adhesion tripeptidyl sequence, Arg-Gly-Asp (RGD), common to cell adhesive proteins, was photoimmobilized on these surfaces, the surfaces became cell adhesive. Microarchitectured surfaces, which were prepared by sequential procedures of surface coating and photocuring using a photomask with lattice windows, produced regionally differentiated cell adhesiveness.

Photocurable liquid biodegradable copolymers were prepared by ring-opening copolymerization of e-caprolactone (CL) and trimethylene carbonate (TMC) at an equimolar monomer feed ratio in the presence of a polyol as an initiator and tin(II) 2-ethylhexanoate as a catalyst, followed by subsequent coumarin derivatization at their hydroxyl terminus. These liquid copolymers (molecular weight range from approximately 2500 to 12 000), tri- and tetracoumarinated copolymers, were cross-linked by ultraviolet (UV) light irradiation. Photocuring was enhanced by higher coumarin functionality, higher UV intensity, and reducing the thickness of the liquid film precursor. Stereolithographically prepared microarchitectured surfaces were demonstrated for potential applications in biomedical fields. Keywords: photocuring, liquid copolymer, e-caprolactone, trimethylene carbonate, coumarin

Additional spectroscopic studies have been carried out on jet-cooled 7-azaindole and 7-azaindole clusters with polar solvent adducts, primarily water. New lifetime data and more extended excitation scans strengthen an earlier conclusion that S1 levels mix with nearby levels from another electronic state. Our complete data set indicates the likelihood of mixing with 1La rather than with nπ*, as was previously postulated. The excitation and dispersed emission spectra suggest that addition of one water to the chromophore induces 1La emission. Polar solvent induction of 1La emission in 7-azaindole bears some similarities to analogous phenomena in conventional indoles.

This book reports and rationalizes the state-of-the-art concerning the social costs of electricity generation. Social costs are assessed by adding to the private generation costs, the external costs associated with damages to human health, the environment, crops, materials, and those related to the consequences of climate change. The authors consider the evolution of these costs up to 2030 for major electricity generating technologies and, using these estimates, evaluate policy options for external cost internalization, providing quantitative scenarios by country and primary fuel for 2010, 2020 and 2030. While mainly focusing on European countries, the book also examines the situation in key emerging economies such as China, India, Brazil and Turkey.

Bandwidth requirements in the tactical satellite communications (SATCOM) environment are driven by widely varying battle dynamics. Problematically, however, SATCOM resource management is static, with capacity provisioning based on anticipated average peak demand. To overcome the inevitable shortfalls inherent in this approach, two capabilities are required. The first is integrated situational awareness (SA) of SATCOM network status, including views of disruptions and associated impacts. The second required capability is the ability to allocate bandwidth in near real-time to better meet the urgent needs of Warfighters. This paper describes management architectures in which policy-based automation is applied to the dynamic bandwidth allocation problem for tactical satellite networks using policies derived from both current and near-term historical SA data. Resource management, within the broader policy-based network management, needs to track satellite resource pool capacity, current utilization, and allocation based on instantaneous demand. Dynamic allocation of bulk capacity and admission of more granular per data flow level traffic needs to be governed by policies comprising location, time, organization, associated priorities, etc. Simulated communications traffic resulting from realistic operational scenarios is used to analyze dynamic policy-based resource management. Also presented is a design approach and test bed for live demonstrations of policy-based resource management of Internet Protocol (IP) flows over SPACEWAY, a commercial Ka-band multiple-beam packet processing satellite system, interconnected with a terrestrial IP network.

The desire for satellite-based airborne communications on the move (COTM) has been an emerging trend in recent communication systems. This has been true for both DoD and Civilian systems being deployed. Early implementations of COTM have mostly been focused on the Land-Mobile environment, but this is starting to broaden into other domains as well. There is burgeoning domestic and international interest in airborne platforms to provide high-speed broadband communications. The predominant satellite-based implementations to date have been at frequencies such as L-band, which offers some benefits with omni-directional antennas and large coverage areas. However, these frequency ranges suffer from relatively low data rates (e.g., in the kbps range), overcrowding in key areas of operation, and expensive costs for end users. This has created a desire to shift some of the airborne communications to available Ku and Ka bands, both commercial and military. This paper will clarify the challenges of the airborne environment for satellite communications and present solutions for each of them. Areas that are especially challenging include satellite handover, Doppler correction, and coverage areas. Also, the results of a recent airborne demonstration with very small aperture terminals (VSAT)s are presented to validate a solution to this difficult but indispensable capability.

This paper examines existing measures taken to protect the coastal zones of the Mediterranean Sea and assesses their success. A summary of the main pressures facing these zones is given, followed by an analysis of the legislation covering coastal zone development in ten countries: Algeria, Croatia, Egypt, France, Israel, Italy, Malta, Spain, Tunisia and Turkey. We find that not all of these states have legislation specifically covering coastal zones, but there is concern in all areas that the legislation is not working, We also look at the costs and benefits of controlling coastal development. Firstly, a literature review of valuation studies identifies a range of values placed on developed and undeveloped coastline for both users and local property owners. These values were then used in a model to evaluate policy options to control development of a stretch of coastline. The model indicates that a stricter control regime of coastal development may provide significant benefits.