Local Environment Research Articles

Desktop as a Service using Local Computers

Abstract: Desktop-as-a-Service (DaaS) has gained prominence as a cloud-based solution for delivering desktop environments to users. However, traditional DaaS models often rely on remote data centers, posing concerns regarding data security, latency, and dependence on external infrastructure. In this paper, we propose a paradigm shift by introducing a novel approach to DaaS that leverages the untapped potential of local computing resources.Our system harnesses the idle computing power available within the user's local environment, including desktops, laptops, and servers, to create a distributed DaaS platform. By integrating virtualization technologies and dynamic resource allocation strategies, we enable the provisioning of desktop environments ondemand, effectively reducing the reliance on centralized data centers. Key components of our system include a centralized management platform for orchestrating resource allocation and workload distribution, virtualization techniques for isolating and managing desktop instances, and robust security measures to safeguard sensitive data. Through experimental validation, we demonstrate the feasibility and performance of our approach, showcasing improvements in data privacy, latency reduction, and resource utilization compared to traditional DaaS models. Our research presents a significant step towards decentralized and resilient computing ecosystems, offering users greater control over their desktop environments while maintaining the scalability and accessibility inherent to DaaS paradigms

Classification of complex local environments in systems of particle shapes through shape symmetry-encoded data augmentation.

Detecting and analyzing the local environment is crucial for investigating the dynamical processes of crystal nucleation and shape colloidal particle self-assembly. Recent developments in machine learning provide a promising avenue for better order parameters in complex systems that are challenging to study using traditional approaches. However, the application of machine learning to self-assembly on systems of particle shapes is still underexplored. To address this gap, we propose a simple, physics-agnostic, yet powerful approach that involves training a multilayer perceptron (MLP) as a local environment classifier for systems of particle shapes, using input features such as particle distances and orientations. Our MLP classifier is trained in a supervised manner with a shape symmetry-encoded data augmentation technique without the need for any conventional roto-translations invariant symmetry functions. We evaluate the performance of our classifiers on four different scenarios involving self-assembly of cubic structures, two-dimensional and three-dimensional patchy particle shape systems, hexagonal bipyramids with varying aspect ratios, and truncated shapes with different degrees of truncation. The proposed training process and data augmentation technique are both straightforward and flexible, enabling easy application of the classifier to other processes involving particle orientations. Our work thus presents a valuable tool for investigating self-assembly processes on systems of particle shapes, with potential applications in structure identification of any particle-based or molecular system where orientations can be defined.

Solvation dynamics on the diffusion timescale elucidated using energy-represented dynamics theory.

Photoexcitation of a solute alters the solute-solvent interaction, resulting in the nonequilibrium relaxation of the solvation structure, often called a dynamic Stokes shift or solvation dynamics. Thanks to the local nature of the solute-solvent interaction, the characteristics of the local solvent environment dissolving the solute can be captured by the observation of this process. Recently, we derived the energy-represented Smoluchowski-Vlasov (ERSV) equation, a diffusion equation for molecular liquids, which can be used to analyze the solvation dynamics on the diffusion timescale. This equation expresses the time development for the solvent distribution on the solute-solvent pair interaction energy (energy coordinate). Since the energy coordinate can effectively treat the solvent flexibility in addition to the position and orientation, the ERSV equation can be utilized in various solvent systems. Here, we apply the ERSV equation to the solvation dynamics of 6-propionyl-2-dimethylamino naphthalene (Prodan) in water and different alcohol solvents (methanol, ethanol, and 1-propanol) for clarifying the differences of the relaxation processes among these solvents. Prodan is a solvent-sensitive fluorescent probe and is thus widely utilized for investigating heterogeneous environments. On the long timescale, the ERSV equation satisfactorily reproduces the relaxation time correlation functions obtained from the molecular dynamics (MD) simulations for these solvents. We reveal that the relaxation time coefficient on the diffusion timescale linearly correlates with the inverse of the translational diffusion coefficients for the alcohol solvents because of the Prodan-solvent energy distributions among the alcohols. In the case of water, the time coefficient deviates from the linear relationship for the alcohols due to the difference in the extent of importance of the collective motion between the water and alcohol solvents.

Precisely Engineering Asymmetric Atomic CoN4 by Electron Donating and Extracting for Oxygen Reduction Reaction

AbstractThe development of nonpyrolytic catalysts featuring precisely defined active sites represents an effective strategy for investigating the fundamental relationship between the catalytic activity of oxygen reduction reaction (ORR) catalysts and their local coordination environments. In this study, we have synthesized a series of model electrocatalysts with well‐defined CoN4 centers and nonplanar symmetric coordination structures. These catalysts were prepared by a sequential process involving the chelation of cobalt salts and 1,10‐phenanthroline‐based ligands with various substituent groups (phen(X), where X=OH, CH3, H, Br, Cl) onto covalent triazine frameworks (CTFs). By modulating the electron‐donating or electron‐withdrawing properties of the substituent groups on the phen‐based ligands, the electron density surrounding the CoN4 centers was effectively controlled. Our results demonstrated a direct correlation between the catalytic activity of the CoN4 centers and the electron‐donating ability of the substituent group on the phenanthroline ligands. Notably, the catalyst denoted as BCTF−Co‐phen(OH), featuring the electron‐donating OH group, exhibited the highest ORR catalytic activity. This custom‐crafted catalyst achieved a remarkable half‐wave potential of up to 0.80 V vs. RHE and an impressive turnover frequency (TOF) value of 47.4×10−3 Hz at 0.80 V vs. RHE in an alkaline environment.

Precisely Engineering Asymmetric Atomic CoN4 by Electron Donating and Extracting for Oxygen Reduction Reaction.

The development of nonpyrolytic catalysts featuring precisely defined active sites represents an effective strategy for investigating the fundamental relationship between the catalytic activity of oxygen reduction reaction (ORR) catalysts and their local coordination environments. In this study, we have synthesized a series of model electrocatalysts with well-defined CoN4 centers and nonplanar symmetric coordination structures. These catalysts were prepared by a sequential process involving the chelation of cobalt salts and 1,10-phenanthroline-based ligands with various substituent groups (phen(X), where X=OH, CH3, H, Br, Cl) onto covalent triazine frameworks (CTFs). By modulating the electron-donating or electron-withdrawing properties of the substituent groups on the phen-based ligands, the electron density surrounding the CoN4 centers was effectively controlled. Our results demonstrated a direct correlation between the catalytic activity of the CoN4 centers and the electron-donating ability of the substituent group on the phenanthroline ligands. Notably, the catalyst denoted as BCTF-Co-phen(OH), featuring the electron-donating OH group, exhibited the highest ORR catalytic activity. This custom-crafted catalyst achieved a remarkable half-wave potential of up to 0.80 V vs. RHE and an impressive turnover frequency (TOF) value of 47.4×10-3 Hz at 0.80 V vs. RHE in an alkaline environment.

Tandem Acidic CO2 Electrolysis Coupled with Syngas Fermentation: A Two-Stage Process for Producing Medium-Chain Fatty Acids.

The tandem application of CO2 electrolysis with syngas fermentation holds promise for achieving heightened production rates and improved product quality. However, the significant impact of syngas composition on mixed culture-based microbial chain elongation remains unclear. Additionally, effective methods for generating syngas with an adjustable composition from acidic CO2 electrolysis are currently lacking. This study successfully demonstrated the production of medium-chain fatty acids from CO2 through tandem acidic electrolysis with syngas fermentation. CO could serve as the sole energy source or as the electron donor (when cofed with acetate) for caproate generation. Furthermore, the results of gas diffusion electrode structure engineering highlighted that the use of carbon black, either alone or in combination with graphite, enabled consistent syngas generation with an adjustable composition from acidic CO2 electrolysis (pH 1). The carbon black layer significantly improved the CO selectivity, increasing from 0% to 43.5% (0.05 M K+) and further to 92.4% (0.5 M K+). This enhancement in performance was attributed to the promotion of K+ accumulation, stabilizing catalytically active sites, rather than creating a localized alkaline environment for CO2-to-CO conversion. This research contributes to the advancement of hybrid technology for sustainable CO2 reduction and chemical production.

Controlling Interfacial Hydrogen Bonding at a Gold Surface: The Effect of Organic Cosolvents.

Water often serves as both a reactant and solvent in electrocatalytic reactions. Interfacial water networks can affect the transport and kinetics of these reactions, e.g., hydrogen evolution reaction and CO2 reduction reaction. Adding cosolvents that influence the hydrogen-bonding (H-bonding) environment, such as dimethyl sulfoxide (DMSO), has the potential to tune the reactivity of these important electrocatalytic reactions by regulating the interfacial local environment and water network. We investigate interfacial H-bonding networks in water-DMSO cosolvent mixtures on gold surfaces by using surface-enhanced infrared absorption spectroscopy and molecular dynamics simulations. Experiments and simulations show that the gold surface is enriched with dehydrated DMSO molecules and the mixture phase-separates to form water clusters. Simulations show a "buckled" water conformation at the surface, further constraining interfacial H-bonding. The small size of these water clusters and the energetically unfavorable H-bond conformations might inhibit H-bonding with bulk water, suppressing the proton diffusion required for efficient hydrogen evolution reaction processes.

The dynamic impact of trade on environment

AbstractUtilizing long‐term and high‐resolution pollution remote sensing data, this study examines the dynamic impact of export expansion on the local environment in China from 2000 to 2020. Regions facing larger export expansion experience more pronounced initial deterioration in local air quality, while followed by a more prominent subsequent environmental improvement, indicating that the environmental impact of trade varies over time. Further analysis reveals that a key driver behind this dynamic change is the adjustment in environmental policies, particularly when local government faces higher pressure in achieving the environmental goals and when the central government takes over environmental monitoring powers. Additionally, under more stringent environmental regulations, regional export growth leads to increased environmental expenditures, concurrently driving localities to reduce heavily polluting engergy inputs such as coal. Our study suggests that environmental policies can facilitate the synergistic development of trade and the environment.

Summary on the Development of Accounting and Auditing Practises towards IFRS-IAS/ISA in Jordan: Historical and Theoretical Perspective

In this article, we take a look at the evolution of accounting in the Middle East [ME] region, with a focus on Jordan. We shall examine the major events in this region’s history and see how they relate to the global accounting agenda, changes in the local and international economic landscape, and other relevant developments. Pay close attention to how cultural and historical factors, in addition to worldwide accounting principles, impact the local accounting environment. The adoption of “International Financial Reporting Standards” [IFRS] by MENA nations is examined, along with the reasons and motives behind it, and the effects on the auditing and accounting professions as a whole. This marks a significant milestone in recent history. This article looks at the history of accounting and auditing in Jordan and how it has developed in relation to the International Accounting and Auditing Standards. It also discusses potential future advances in this field.

Second-Shell N Dopants Regulate Acidic O2 Reduction Pathways on Isolated Pt Sites.

Pt is a well-known benchmark catalyst in the acidic oxygen reduction reaction (ORR) that drives electrochemical O2-to-H2O conversion with maximum chemical energy-to-electricity efficiency. Once dispersing bulk Pt into isolated single atoms, however, the preferential ORR pathway remains a long-standing controversy due to their complex local coordination environment and diverse site density over substrates. Herein, using a set of carbon nanotube supported Pt-N-C single-atom catalysts, we demonstrate how the neighboring N dopants regulate the electronic structure of the Pt central atom and thus steer the ORR selectivity; that is, the O2-to-H2O2 conversion selectivity can be tailored from 10% to 85% at 0.3 V versus reversible hydrogen electrode. Moreover, via a comprehensive X-ray-radiated spectroscopy and shell-isolated nanoparticle-enhanced Raman spectroscopy analysis coupled with theoretical modeling, we reveal that a dominant pyridinic- and pyrrolic-N coordination within the first shell of Pt-N-C motifs favors the 4e- ORR, whereas the introduction of a second-shell graphitic-N dopant weakens *OOH binding on neighboring Pt sites and gives rise to a dominant 2e- ORR. These findings underscore the importance of the chemical environment effect for steering the electrochemical performance of single-atom catalysts.

Synergistic role of Sn-doping on the thermal and electrical properties of sinnerite Cu6As4S9

Sinnerite Cu6As4S9 has been identified as a promising material for optoelectronic applications, with potential for other energy-related applications; however, knowledge of the electrical and thermal properties as well as the mechanisms underlying transport in sinnerite is lacking. We present an investigation of the synthesis, structural, thermal and electrical transport properties of stoichiometric and Sn-doped Cu6As4S9. Sinnerite has a triclinic lattice structure, with highly distorted local atomic coordination environments that, in part, results in its complex structure and bonding. Our results and analyses indicate As 4s2 lone pair-induced distortions and strong lattice anharmonicity that leads to a relatively short phonon mean free path, resulting in intrinsically very low thermal conductivity. The electrical resistivity for both compositions, Cu6As4-xSnxS9 (x = 0, 0.2), are relatively high and varies little with temperature, typical of degenerate semiconductors. An increase in mobility and electrical conductivity was obtained by Sn doping in Cu6As3.8Sn0.2S9. This work demonstrates an effective route to synthesize bulk sinnerite as well as advances the knowledge of the properties of sinnerite, as this and other ternary chalcogenides continue to be of interest for potential technologically significant applications.

Clinical Image: surgery under battery operated headlights

Surgery needs electricity. Dependable power supplies are a major problem in the Global South. Diesel generators, when available, provide a heavily polluting alternative. This image shows Dr. Philip Alexander operating in Kaaza, Spiti Valley, Himachal Pradesh, India, using a battery-operated camping headlight, theatre lights powered with a car battery, and diathermy powered by a diesel generator. Clean, reliable energy that will improve patient outcomes and simultaneously protect the local environment is a priority for hospitals in low and middle income countries.

Towards Routine 7Li In Situ Solid-State NMR Studies of Electrochemical Processes in Li|LiPF6|LFP Cells

AbstractIn this study, electrochemical processes in a Li|LiPF6|LFP cell have been explored applying advanced solid-state NMR technologies. In situ solid-state NMR allows to monitor structural changes in local environments in commercially available cell components during galvanostatic cycling. In collaboration with Dragonfly Energy, ePROBE GmbH and Bruker BioSpin GmbH & Co. KG, we have demonstrated an experimental procedure for routine application of in situ solid-state NMR for battery research. This points out the high potential of this approach for use in the energy storage industry.

'Acceleration' of the food delivery marketplace: Perspectives of local authority professionals in the North-East of England on temporary COVID regulations.

In January 2021, we assessed the implications of temporary regulations in the United Kingdom allowing pubs and restaurants to operate on a takeaway basis without instigating a change of use. Local authorities (LAs) across the North-East of England were unaware of any data regarding the take-up of these regulations, partially due to ongoing capacity issues; participants also raised health concerns around takeaway use increasing significantly. One year on, we repeated the study aiming to understand the impact of these regulations on the policy and practice of key professional groups. Specifically, we wanted to understand if LAs were still struggling with staff capacity to address the regulations, whether professionals still had public health trepidations, and if any unexpected changes had occurred across the local food environment because of the pandemic. We conversed with 16 public health professionals, planners and environmental health officers across seven LAs throughout the North-East of England via focus groups and interviews. Data collated were analysed via an inductive and semantic, reflexive-thematic approach. Through analysis of the data, three themes were generated and are discussed throughout: popular online delivery services as a mediator to increased takeaway usage; potential long-term health implications and challenges; continued uncertainty regarding the temporary regulations. This paper highlights important changes to local food environments, which public health professionals should be aware of, so they are better equipped to tackle health inequalities across urban and sub-urban areas.

When the woolly rhinoceroses roamed East Asia: a review of isotopic paleoecology of the genus Coelodonta from the Tibetan Plateau to northern Eurasia

East Asia, being the evolutionary center of Coelodonta, offers a unique opportunity to explore the spatiotemporal paleoecologies of this genus. This study utilized bulk and serial stable carbon and oxygen isotope analyses on the Coelodonta nihowanensis and other ungulates from the Longdan fauna as well as two modern goats in the Linxia Basin, aiming to explore the paleoecology of C. nihowanensis at the periphery of the Tibetan Plateau during the Early Pleistocene. The isotopic results of these mammals indicated that C3 vegetation was possibly a major component of the local environment in the Linxia Basin, which was influenced by a seasonal summer monsoon. C. nihowanensis specimens in the Longdan fauna were possibly mixed feeders, as indicated by the wide distribution of their δ13C values and the intermediate δ18O values compared to other coexisting ungulates. Moreover, the comparison of the δ13C and δ18O values of similar taxa from the Linxia and Nihewan basins has revealed spatiotemporal differences in the paleoclimate and paleoenvironments of these two regions throughout the Early Pleistocene. This provides a holistic framework for understanding the paleoecology of the C. nihowanensis. The isotopic results of the C. nihowanensis in the Linxia and Nihewan basins suggested varied foraging ecologies across different sites and time spans during the Early Pleistocene. This underscores the adaptability of the C. nihowanensis to diverse environments from west to east in northern China. By scrutinizing the evolutionary ecological history of the woolly rhinoceroses from its ancestor, Coelodonta thibetana, to its final form, Coelodonta antiquitatis, this study sheds light on the ecological adaptation of this genus from the Pliocene to Late Pleistocene, spanning its migration from the Tibetan Plateau to northern Eurasia.

A Community Needs Assessment and Implementation Planning for a Community Exercise Program for Survivors of Stroke: Protocol for a Pilot Hybrid Type I Clinical Effectiveness and Implementation Study.

Physical activity and exercise are important aspects of maintaining health. People with mobility impairments, including survivors of stroke, are less likely to exercise and at greater risk of developing or worsening chronic health conditions. Increasing accessible, desired options for exercise may address the gap in available physical activity programs, provide an opportunity for continued services after rehabilitation, and cultivate social connections for people after stroke and others with mobility impairments. Existing evidence-based community programs for people after stroke target cardiovascular endurance, mobility, walking ability, balance, and education. While much is known about the effectiveness of these programs, it is important to understand the local environment as implementation and sustainment strategies are context-specific. This study protocol aims to evaluate community needs and resources for exercise for adults living with mobility impairments with initial emphasis on survivors of stroke in Richland County, South Carolina. Results will inform a hybrid type I effectiveness and implementation pilot of an evidence-based group exercise program for survivors of stroke. The exploration and preparation phases of the EPIS (Exploration, Preparation, Implementation, and Sustainment) implementation model guide the study. A community needs assessment will evaluate the needs and desires of survivors of stroke through qualitative semistructured interviews with survivors of stroke, rehabilitation professionals, and fitness trainers serving people with mobility impairments. Additional data will be collected from survivors of stroke through a survey. Fitness center sites will be assessed through interviews and the Accessibility Instrument Measuring Fitness and Recreation Environments inventory. Qualitative data will be evaluated using content analysis and supported by mean survey results. Data will be categorized by the community (outer context), potential participants (outer context), and fitness center (inner context) and evaluate needs, resources, barriers, and facilitators. Results will inform evidence-based exercise program selection, adaptations, and specific local implementation strategies to influence success. Pilot outcome measures for participants (clinical effectiveness), process, and program delivery levels will be identified. An implementation logic model for interventions will be created to reflect the design elements for the pilot and their complex interactions. The study was reviewed by the institutional review board and exempt approved on December 19, 2023. The study data collection began in January 2024 and is projected to be completed in June 2024. A total of 17 participants have been interviewed as of manuscript submission. Results are expected to be published in early 2025. Performing a needs assessment before implementing it in the community allows for early identification of complex relationships and preplanning to address problems that cannot be anticipated in controlled effectiveness research. Evaluation and preparation prior to implementation of a community exercise program enhance the potential to be successful, valued, and sustained in the community. DERR1-10.2196/55432.

Analyzing urban scaling laws in the United States over 115 years

The scaling relations between city attributes and population are emergent and ubiquitous aspects of urban growth. Quantifying these relations and understanding their theoretical foundation, however, is difficult due to the challenge of defining city boundaries and a lack of historical data to study city dynamics over time and space. To address this issue, we analyze scaling between city infrastructure and population across 857 metropolitan areas in the conterminous United States over an unprecedented 115 years (1900–2015) using dasymetrically refined historical population estimates, historical urban road network models, and multi-temporal settlement data to define dynamic city boundaries. We demonstrate that urban scaling exponents closely match theoretical models over a century. Despite some close quantitative agreement with theory, the empirical scaling relations unexpectedly vary across regions. Our analysis of scaling coefficients, meanwhile, reveals that contemporary cities use more developed land and kilometers of road than cities of similar population in 1900, which has serious implications for urban development and impacts on the local environment. Overall, our results provide a new way to study urban systems based on novel, geohistorical data.

Neuronally differentiated macula densa cells regulate tissue remodeling and regeneration in the kidney.

Tissue regeneration is limited in several organs including the kidney, contributing to the high prevalence of kidney disease globally. However, evolutionary and physiological adaptive responses and the presence of renal progenitor cells suggest existing remodeling capacity. This study uncovered endogenous tissue remodeling mechanisms in the kidney that were activated by the loss of body fluid and salt and regulated by a unique niche of a minority renal cell type called the macula densa (MD). Here we identified neuronal differentiation features of MD cells that sense the local and systemic environment, secrete angiogenic, growth and extracellular matrix remodeling factors, cytokines and chemokines, and control resident progenitor cells. Serial intravital imaging, MD nerve growth factor receptor and Wnt mouse models and transcriptome analysis revealed cellular and molecular mechanisms of these MD functions. Human and therapeutic translation studies illustrated the clinical potential of MD factors including CCN1 as a urinary biomarker and therapeutic target in chronic kidney disease. The concept that a neuronally differentiated key sensory and regulatory cell type responding to organ-specific physiological inputs controls local progenitors to remodel or repair tissues may be applicable to other organs and diverse tissue regenerative therapeutic strategies.

Spatial ecology of moose in Sweden: Combined Sr-O-C isotope analyses of bone and antler.

The study of spatial (paleo)ecology in mammals is critical to understand how animals adapt to and exploit their environment. In this work we analysed the 87Sr/86Sr, δ18O and δ13C isotope composition of 65 moose bone and antler samples from Sweden from wild-shot individuals dated between 1800 and 1994 to study moose mobility and feeding behaviour for (paleo)ecological applications. Sr data were compared with isoscapes of the Scandinavian region, built ad-hoc during this study, to understand how moose utilise the landscape in Northern Europe. The 87Sr/86Sr isoscape was developed using a machine-learning approach with external geo-environmental predictors and literature data. Similarly, a δ18O isoscape, obtained from average annual precipitation δ18O values, was employed to highlight differences in the isotope composition of the local environment vs. bone/antler. Overall, 82% of the moose samples were compatible with the likely local isotope composition (n = 53), suggesting that they were shot not far from their year-round dwelling area. 'Local' samples were used to calibrate the two isoscapes, to improve the prediction of provenance for the presumably 'non-local' individuals. For the latter (n = 12, of which two are antlers and ten are bones), the probability of geographic origin was estimated using a Bayesian approach by combining the two isoscapes. Interestingly, two of these samples (one antler and one bone) seem to come from areas more than 250 km away from the place where the animals were hunted, indicating a possible remarkable intra-annual mobility. Finally, the δ13C data were compared with the forest cover of Sweden and ultimately used to understand the dietary preference of moose. We interpreted a difference in δ13C values of antlers (13C-enriched) and bones (13C-depleted) as a joint effect of seasonal variations in moose diet and, possibly, physiological stresses during winter-time, i.e., increased consumption of endogenous 13C-depleted lipids.

Indirect control of band gaps by manipulating local atomic environments using solid solutions and co-doping

Abstract The ability to tune band gaps of semiconductors is important for many optoelectronics applications including photocatalysis. A common approach to this is doping, but this often has the disadvantage of introducing defect states in the electronic structure that can result in poor charge mobility and increased recombination losses. In this work, density functional theory calculations are used to understand how co-doping and solid solution formation can allow tuning of semiconductor band gaps through indirect effects. The addition of ZnS to GaP alters the local atomic environments of the Ga and P atoms, resulting in shifts in the energies of the Ga and P states that form the valence and conduction band edges, and hence changes the band gap without altering which atoms form the band edges, providing an explanation for previous experimental observations. Similarly, N doping of ZnO is known from previous experimental work to reduce the band gap and increase visible-light absorption; here we show that, when co-doped with Al, the Al changes the local environment of the N atoms, providing further control of the band gap without introducing new states within the band gap or at the band edges, while also providing an energetically more favourable state than N-doped ZnO. Replacing Al with elements of different electronegativity is an additional tool for band gap tuning, since the different electronegativities correspond to different effects on the N local environment. The consistency in the parameters identified here that control the band gaps across the various systems studied indicates some general concepts that can be applied in tuning the band gaps of semiconductors, without or only minimally affecting charge mobility.