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Cover page of Dirac lines and loop at the Fermi level in the time-reversal symmetry breaking superconductor LaNiGa2

Dirac lines and loop at the Fermi level in the time-reversal symmetry breaking superconductor LaNiGa2

(2022)

Unconventional superconductors have Cooper pairs with lower symmetries than in conventional superconductors. In most unconventional superconductors, the additional symmetry breaking occurs in relation to typical ingredients such as strongly correlated Fermi liquid phases, magnetic fluctuations, or strong spin-orbit coupling in noncentrosymmetric structures. In this article, we show that the time-reversal symmetry breaking in the superconductor LaNiGa2 is enabled by its previously unknown topological electronic band structure, with Dirac lines and a Dirac loop at the Fermi level. Two symmetry related Dirac points even remain degenerate under spin-orbit coupling. These unique topological features enable an unconventional superconducting gap in which time-reversal symmetry can be broken in the absence of other typical ingredients. Our findings provide a route to identify a new type of unconventional superconductors based on nonsymmorphic symmetries and will enable future discoveries of topological crystalline superconductors.

Acquired insights from the long-term surveillance of SARS-CoV-2 RNA for COVID-19 monitoring: The case of Monterrey Metropolitan Area (Mexico).

(2022)

Wastewater-based epidemiology offers a time- and cost-effective way to monitor SARS-CoV-2 spread in communities and therefore represents a complement to clinical testing. WBE applicability has been demonstrated in a number of cases over short-term periods as a method for tracking the prevalence of SARS-CoV-2 and an early-warning tool for predicting outbreaks in the population. This study reports SARS-CoV-2 viral loads from wastewater treatment plants (WWTPs) and hospitals over a 6-month period (June to December 2020). Results show that the overall range of viral load in positive tested samples was between 1.2 × 103 and 3.5 × 106 gene copies/l, unveiling that secondary-treated wastewaters mirrored the viral load of influents. The interpretation suggests that the viral titers found in three out of four WWTPs were associated to clinical COVID-19 surveillance indicators preceding 2-7 days the rise of reported clinical cases. The median wastewater detection rate of SARS-CoV-2 was one out of 14,300 reported new cases. Preliminary model estimates of prevalence ranged from 0.02 to 4.6% for the studied period. This comprehensive statistical and epidemiological analysis demonstrates that the applied wastewater-based approach to COVID-19 surveillance is in general consistent and feasible, although there is room for improvements.

Assessing Factor V Antigen and Degradation Products in Burn and Trauma Patients.

(2022)

Introduction

Proposed mechanisms of acute traumatic coagulopathy (ATC) include decreased clotting potential due to factor consumption and proteolytic inactivation of factor V (FV) and activated factor V (FVa) by activated protein C (aPC). The role of FV/FVa depletion or inactivation in burn-induced coagulopathy is not well characterized. This study evaluates FV dynamics following burn and nonburn trauma.

Methods

Burn and trauma patients were prospectively enrolled. Western blotting was performed on admission plasma to quantitate levels of FV antigen and to assess for aPC or other proteolytically derived FV/FVa degradation products. Statistical analysis was performed with Spearman's, Chi-square, Mann-Whitney U test, and logistic regression.

Results

Burn (n = 60) and trauma (n = 136) cohorts showed similar degrees of FV consumption with median FV levels of 76% versus 73% (P = 0.65) of normal, respectively. Percent total body surface area (TBSA) was not correlated with FV, nor were significant differences in median FV levels observed between low and high TBSA groups. The injury severity score (ISS) in trauma patients was inversely correlated with FV (ρ = -0.26; P = 0.01) and ISS ≥ 25 was associated with a lower FV antigen level (64% versus. 93%; P = 0.009). The proportion of samples showing proteolysis-derived FV was greater in trauma than burn patients (42% versus. 16%; P = 0.0006).

Conclusions

Increasing traumatic injury severity is associated with decreased FV antigen levels, and a greater proportion of trauma patient samples exhibit proteolytically degraded FV fragments. These associations are not present in burns, suggesting that mechanisms underlying FV depletion in burn and nonburn trauma are not identical.

Cover page of Microplastic ingestion from atmospheric deposition during dining/drinking activities.

Microplastic ingestion from atmospheric deposition during dining/drinking activities.

(2022)

Human-health risks from microplastics have attracted considerable attention, but little is known about human-exposure pathways and intensities. Recent studies posited that inhalation of atmospheric microplastics was the dominant human-exposure pathway. Herein, our study identified that atmospheric microplastics ingested from deposition during routine dining/drinking activities represent another important exposure pathway. We measured abundances of atmospheric-deposited microplastics of up to 105 items m-2 d-1 in dining/drinking venues, with 90% smaller than 100 µm and a dominance of amorphous fragments rather than fibers. Typical work-life scenarios projected an annual ingestion of 1.9 × 105 to 1.3 × 106 microplastics through atmospheric deposition on diet, with higher exposure rates for indoor versus outdoor dining/drinking settings. Ingestion of atmospheric-deposited microplastics through diet was similar in magnitude to presumed inhalation exposure, but 2-3 orders of magnitude greater than direct ingestion from food sources. Simple mitigation strategies (e.g., covering and rinsing dishware) can substantially reduce the exposure of atmospheric deposition microplastics through diet.

Restaurant dining during the COVID-19 pandemic among adults with low-income in the United States.

(2022)

The COVID-19 pandemic caused widespread non-essential business closures in the U.S., which may have disproportionately impacted food consumption in lower-income communities, in part due to reduced access to healthy and affordable foods, as well as occupations that may have required working outside the home. The aims of this study were to examine restaurant dining behaviors (including drive-through, takeout, and delivery) at fast-food and non-fast-food (i.e., fast casual and full-service ['other']) restaurants and the impact on diet quality among racially/ethnically diverse low-income adults during the early months of the pandemic. Participants completed an online survey using CloudResearch regarding restaurant dining behaviors in the past week (during June 2020) and during a typical week prior to the pandemic. Diet quality was measured using the Prime Diet Quality Score (PDQS). Surveys from 1,756 low-income adults (incomes <250% of the Federal Poverty Level) were analyzed using chi-squared tests to examine differences in demographic characteristics among those dining at restaurants during the pandemic, as well as to examine differences in dining frequency compared with prior to COVID-19. Negative binomial regressions were used to examine the mean frequency of eating food from fast-food and other restaurants, adjusted for socio-demographic characteristics. This study found reductions in fast-food and other restaurant dining compared with prior to COVID-19, although overall restaurant consumption remained high with over half of participants reporting fast-food consumption in the week prior (average consumption of twice per week). Greater fast-food consumption was associated with poorer diet quality. In conclusion, while fast-food consumption was slightly lower during the pandemic, the overall high levels observed among socioeconomically disadvantaged adults remains concerning, highlighting the continued need for initiatives and policies to encourage greater access to and consumption of affordable and healthier foods.

Cover page of Triclosan targets miR-144 abnormal expression to induce neurodevelopmental toxicity mediated by activating PKC/MAPK signaling pathway.

Triclosan targets miR-144 abnormal expression to induce neurodevelopmental toxicity mediated by activating PKC/MAPK signaling pathway.

(2022)

Although the previous research confirmed that triclosan (TCS) induced an estrogen effect by acting on a novel G-protein coupled estrogen-membrane receptor (GPER), the underlying mechanisms by which downstream pathways induce neurotoxicity remain unclear after TCS activation of GPER. By employing a series of techniques (Illumina miRNA-seq, RT-qPCR, and artificial intervention of miRNA expression), we screened out four important miRNAs, whose target genes were directly/indirectly involved in neurodevelopment and neurobehavior. Especially, the miR-144 up-regulation caused vascular malformation and severely affected hair-cell development and lateral-line-neuromast formation, thereby causing abnormal motor behavior. After microinjecting 1-2-cell embryos, the similar phenotypic malformations as those induced by TCS were observed, including aberrant neuromast, cuticular-plate development and motor behavior. By KEGG pathway enrichment analysis, these target genes were demonstrated to be mainly related to the PKC/MAPK signaling pathway. When a PKC inhibitor was used to suppress the PKC/MAPK pathway, a substantial alleviation of TCS-induced neurotoxicity was observed. Therefore, TCS acts on GPER to activate the downstream PKC/MAPK signaling pathway, further up-regulating miR-144 expression and causing abnormal modulation of these nerve-related genes to trigger neurodevelopmental toxicity. These findings unravel the molecular mechanisms of TCS-induced neurodegenerative diseases, and offer theoretical guidance for TCS-pollution early warning and management.

Cover page of An energy-based analysis framework for soil structure interaction systems

An energy-based analysis framework for soil structure interaction systems

(2022)

Presented is an energy-based analysis and design framework for soil structure interaction system. Theoretical formulation based on thermodynamics and engineering mechanics for calculating energy dissipation in soil and structural elastic plastic finite elements is presented and discussed. The importance of incorporation of plastic free energy, that ensures nonnegative incremental energy dissipation, also known as the second law of thermodynamics, is emphasized. For application to practical engineering problems, the presented framework is implemented in the Real-ESSI Simulator and visualized using ParaView. In order to illustrate the proposed framework, a practical model composed of a reinforced concrete frame structure, underlying soil, and soil-foundation interface is developed and analyzed. Elastic-plastic material model and viscous, Rayleigh damping parameters are calibrated to represent typical realistic cases. Spatial and time distribution of energy dissipation density is analyzed and discussed. Locations with high plastic energy dissipation, used as a proxy for material and structural damage are identified. In addition, locations of high plastic energy dissipation within soil and soil-foundation interface, that are used to dissipate seismic energy before it reaches structure, are also identified. Influences of input seismic motion scale and design variation on system performance are investigated. It is shown that traditional displacement-based design parameters, such as peak displacement and maximum interstory drift ratio, could underestimate the change of system performance when different seismic motion scale or structural design are used.

Empowering saving energy at home through serious games on thermostat interfaces

(2022)

The residential Heating Ventilation and Air-Conditioning (HVAC) system use around 3/5 of the total energy consumption. Connected thermostats optimize the HVAC operation; however, householders have personality traits that lead into behavioral and usability problems toward the thermostat's interface usage. Thus, a serious game applied in the thermostat interface can balance entertainment and education. Therefore, thermostat interfaces must address strategies that reduce energy without losing thermal comfort. This paper proposed an interactive interface type and a predicted interface type based on an HVAC strategy and a Natural Ventilation strategy. These strategies measured the impact of adaptive thermal comfort, energy consumption, and costs. Hence, twelve energy models located in California (Concord, Riverside, Los Angeles, and San Diego) were simulated using EnergyPlus™ through LadybugTools. The first interactive interface included Serious Game elements, so the householder interacted with the date, location, and setpoint. The second interface predicted the energy consumption and thermal comfort during winter and summer in Concord by a two-layer feed-forward Artificial Neural Network structure. The proposed structure decreases the energy consumption by at least 62% without losing thermal comfort.

Folk Labeling: Insights on Improving Usability and Saving Energy Gleaned from After-Market Graffiti on Common Appliances.

(2022)

The after-market labeling of a device by its users often indicates problematic usability, which can affect the device's energy consumption. For example, when people find a lighting control panel difficult to use, they often write instructions on a piece of paper and affix it nearby as a reminder to themselves and to help others. We collected over a hundred examples of these “folk labels” from commercial and residential buildings through an online contest inviting people to upload photos of folk label examples, informal solicitation of colleagues, online searches, and personal observation. Some folk labels offered guidance or reminders (e.g., turn off light before fan on a projector); some provided specific instructions for multi-function controls or addressed problems identifying orientation or direction (right/left, on/off). We categorized these folk labels (e.g., by location, subject, form, etc.), and analyzed them according to usability guidelines and heuristics1 . In addition, we evaluated their potential impact on energy consumption. We found that most folk labels indicated usability issues in three areas: visibility of available options, natural mappings, and consistency. For example, one light switch looked like a simple toggle ON-OFF control, but actually could control various dimming options (violated “visibility of available options” principle). One would naturally turn the light on full power if one did not know how to use the dimming capability. We discovered that folk labeling provides a simple means of identifying usability problems.

Cover page of Foundations for California's Water Security in a Changing Climate

Foundations for California's Water Security in a Changing Climate

(2022)

California’s water supplies are facing unprecedented stresses, and the state’s water-management systems are struggling to meet both environmental and human needs (agricultural, municipal, industrial). Supplies are highly vulnerable to climate variability and extreme events, limiting options to respond to the combined stresses of a changing climate, population, and land cover. Strategic, coordinated investments in California’s water infrastructure, institutions, and information will provide the foundation for a secure, equitable, and efficient water future. The cornerstone of water security, and priority need for California, is a modern, robust water-information system that enables accurate, timely, and transparent accounting through the water-supply and use cycle. This system must extend from mountain headwaters through valley groundwater. Investments are also needed in capacity building for use of water information among institutions and stakeholders across the state. Priority infrastructure improvements are needed for central elements of the state’s “green” infrastructure: restoration of Sierra Nevada and other forests in source-water areas, and additional groundwater recharge on farmland and expanded floodplains. With better-informed management, California’s existing water supplies could go further to meeting the state’s urban, agricultural, ecological, and industrial needs.