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Background: Disproportionate exposure to poor food environments and food insecurity among Black Americans may partially explain critical chronic disease disparities by race and ethnicity. A complex set of structural factors and interactions between Black residents and their food environments, including store types, quantity, proximity, and quality of goods and consumer interactions within stores, may affect nutritional behaviors and contribute to higher cardiovascular and kidney disease risk. Methods: We used the Photovoice methodology to explore the food environment in Baltimore, MD, through the perspectives of Black residents with hypertension between August and November 2019. Twenty-four participants were enrolled in the study (mean age: 65.1 years; 67% female). After a brief photography training, participants captured photos of their food environment, which they discussed in small focus groups over the course of 5 weeks. Discussions were audiotaped and analyzed for emergent themes using a line-by-line inductive approach. Themes were, then, organized into a collective narrative. Results: Findings describe physical and social features of the food environment as well as participants’ perceptions of its origins and holistic and generational health effects. The study illustrates the interrelationships among the broader socio-political environment, the quality and quantity of stores in the food landscape, and the ways in which they engage with the food environment as residents and consumers who have been marginalized due to their race and/or social class. The following meta-themes emerged from the data: (1) social injustice; (2) structural racism and classism; (3) interpersonal racism; (4) generational effects; (5) mistrust; (6) social programs; and (7) community asset-based approaches, including advocacy and civic engagement. Conclusions: Understanding residents’ perceptions of the foundations and effects of the food environment on their health may help stakeholders to cocreate multilevel interventions alongside residents to improve access to healthy food and health outcomes among disparities affected populations.

Rural residents not only produce rural garbage and participate in its disposal, but are also beneficiaries of a beautiful rural environment. The garbage exchange supermarket (where garbage is exchanged for goods) is a garbage disposal method that is employed in some villages in China. It is of great significance for the improvement of rural living environment and rural residents’ awareness of environmental protection. Thus, it is necessary to explore rural residents’ perceptions and behavior regarding garbage exchange supermarkets. Based on planned behavior theory and social exchange theory, this paper develops a model of rural residents’ perceptions, attitudes, and environmentally responsible behaviors regarding garbage exchange supermarkets. Then, using Huangshan City, China, as a case study, three villages, located in the upper, middle, and lower reaches of the Xin’an River were selected. Using a stratified sampling method, 324 questionnaires were obtained from residents. The developed model was verified by the method of structural equation modeling. Findings are as follows: (1) On the whole, residents have a strong and positive perception of the benefits of garbage exchange supermarkets, with an emphasis on its environmental advantages. (2) Regarding the cost dimension in perception, the focus is spent queuing for exchange on the time and sorting garbage at home. In general, residents are still willing to spend this time going to the supermarket to exchange. (3) Environmentally responsible behavior is divided into two dimensions: compliance and promotion-type environmentally responsible behavior—the former is more apparent among rural residents. (4) Residents’ perceptions of benefits positively affect their attitudes and satisfaction towards garbage exchange supermarkets. Cost perception has no significant effect on residents’ attitudes but has a negative correlation with satisfaction, satisfaction and attitude have positive correlations with environmentally responsible behavior, and satisfaction also positively affects residents’ attitudes.

Regulating SOS1 functions may result in targeted pan-KRAS therapies. Small-molecule SOS1 inhibitors showed promising anticancer potential, and the most advanced inhibitor BI 1701963 is currently under phase I clinical studies. SOS1 agonists provide new opportunities to treat cancer; however, the underlying mechanisms still warrant investigation. We here report the discovery of the first SOS1 PROTACs designed uniquely by connecting a VHL ligand to the reported SOS1 agonist, ensuring that the observed inhibitory activity results from degraders. The best compound

Poor food environments and disproportionate food insecurity among African Americans (AAs) represent determinants of chronic disease disparities by race/ethnicity. We used PhotoVoice to explore the food environment in Baltimore, MD, through the perspectives of Black residents with hypertension. Findings illuminated structural racism and classism as root causes of “food desert” conditions. Respondents provided critical analysis of existing food access barriers, including problematic policies, and offered asset-based solutions. Using an exhibition of participants’ photographs to set the tone of the discussion, we will convene a stakeholder meeting including study participants, community advisory board members, local and state government agencies, civic organizations, community farmers, agricultural organizations, non-profit food providers, churches, local restauranteurs, convenience store owners, insurance payers, and transportation providers. Discussion will center on three areas of action informed by findings: systems level issues; individual activation, agency, and advocacy; and community-based solutions. Meeting proceedings will be disseminated through academic and lay publications.

The Southwest Transboundary Basin (STB), which contains a part of the Tibetan Plateau and Southwest China, covers a large area of grassland that has been experiencing significant climate change (Cc) and human activities (Ha). However, variabilities of the grasslands and respective contributions of the drivers have not been fully understood. In this study, we quantitatively investigated the influences of Cc and Ha on the grasslands from 1982 to 2015 across the STB, using residual analysis, trend analysis, and partial correlation analysis. Particularly, vapor pressure deficit (VPD), which is increasingly paid attention to in current studies, was included in our analysis as a critical driver of alpine grasslands. Additionally, a new method, pure climate-induced grassland pixel, which combined the coefficient of variation, was proposed to significantly improve the pixel purity with higher coefficient correlation and lower error and bias. Results show that changes in the climate play an important role in the grassland coverage of STB during 1982-1999 and 2000-2015, while Ha only had a relatively weak negative impact on grassland during 2000-2015, mainly in the Lancang River Basin. Specifically, the grasslands showed an increasing trend in 1982-1999, dominated by climate change with a contribution rate of 80.87%. Temperature had the greatest contribution, followed by VPD and precipitation in this period. On the contrary, the grasslands showed a decreasing trend in 2000-2015, dominated by both Cc and Ha with the contributions of 53.16% and 46.84%, respectively. The findings of this study provide a valuable reference for future ecological restoration in other similar alpine regions.

The smooth integration of counting and absolute deviation (SICA) penalty has been demonstrated theoretically and practically to be effective in nonconvex penalization for variable selection and par...

Stochastic variance reduced gradient (SVRG) is a popular variance reduction technique for accelerating stochastic gradient descent (SGD). We provide a first analysis of the method for solving a class of linear inverse problems in the lens of the classical regularization theory. We prove that for a suitable constant step size schedule, the method can achieve an optimal convergence rate in terms of the noise level (under suitable regularity condition) and the variance of the SVRG iterate error is smaller than that by SGD. These theoretical findings are corroborated by a set of numerical experiments., Comment: 31 pages, 2 figures, to appear at Inverse Problems

Single photon light detection and ranging (LiDAR) has the advantages of high angle and distance resolution, great concealment, a strong anti-active jamming capability, small volume, and light mass, and has been widely applied in marine reconnaissance, obstacle avoidance, chemical warfare agent detection, and navigation. With the rapid development of metamaterials, the performance of a single photon LiDAR system would be improved by optimizing the core devices in the system. In this paper, we first analyzed the performance index of the single photon LiDAR and discovered the potential of metamaterials in improving the system performance. Then, the influence of metamaterials on the core devices of the single photon LiDAR were discussed, including lasers, scanning devices, optical lenses, and single photon detectors. As a result, we have concluded that through effective light field modulation, metamaterial technology might enhance the performance innovation of the single photon LiDAR.

Introduction: Poor food environment and disproportionate food insecurity among African Americans represent determinants of chronic disease disparities by race/ethnicity. The presence of a supermarket could lead to a 32 percent increase in fruit and vegetable consumption among AAs, yet a complex set of barriers may make it difficult to participate in healthy nutrition. We examined the food environment in Baltimore, MD, through the perspectives of African Americans with hypertension. Methods: Photovoice is a community-based participatory research tool that uses photography to engage participants in reflection and dialogue regarding their community's strengths, needs, and capacity for social change. We recruited 24 residents of Baltimore who met initial demographic—age (21 years or older), race (African American), and clinical criteria (hypertension) for the Five Plus Nuts and Beans for Kidneys study—a randomized control trial of a dietary intervention, but were ultimately found ineligible. After photography training, participants responded to “Photograph everything related to food in your neighborhood” and discussed their images over 4 sessions. Audiotaped conversations were analyzed for common themes. Results: Through this formative, community-engaged process, residents deemed the food environment reflective of the race of the neighborhood’s occupants with low-income Blacks consistently situated at the disadvantaged end. Participants expressed the lack of access to food—a resource that they deemed should be accessible to all—as a catalyst of crime, a point of racial injustice, and a stumbling block in improving their health. Residents identified both individual- and system-level barriers and facilitators to eating healthy foods. Conclusions: Engaging community voices and taking stock of the nuances of the food environment, including its construction and subsequent impact on residents’ outcomes, may inform clinical practice and health policy. Photos will be exhibited and used during a moderated conversation on the food environment among multiple stakeholders in Baltimore, including viable solutions to the “food desert” conditions and opportunities to address racial disparities in chronic disease.

Stochastic gradient descent (SGD) is a promising method for solving large-scale inverse problems, due to its excellent scalability with respect to data size. The current mathematical theory in the lens of regularization theory predicts that SGD with a polynomially decaying stepsize schedule may suffer from an undesirable saturation phenomenon, i.e., the convergence rate does not further improve with the solution regularity index when it is beyond a certain range. In this work, we present a refined convergence rate analysis of SGD, and prove that saturation actually does not occur if the initial stepsize of the schedule is sufficiently small. Several numerical experiments are provided to complement the analysis., to appear at SIAM/ASA J. Uncertainty Quantification, with error corrected

Multiple ion beam facilities are powerful tools to simulate the irradiation effects of neutrons on relevant nuclear materials. Since hydrogen and helium are often generated in neutron irradiated materials as transmutation products and they play important roles in the defect evolution, the triple beam accelerator and transmission electron microscope link in situ facility instead of a monobeam or dual-beam facility is necessary to simulate neutron irradiation. A hydrogen-helium dual-beam ion implanter has been developed for a triple ion beam in situ facility at Xiamen University. A Penning ion source has been developed to produce H2+ and He+ simultaneously. A special system consisting of two Wien filters and an Einzel lens has been proposed to purify the species from a single Penning source and allow for the measurement of the He+/H2+ ratio, without disturbing the accelerator settings. The detail of this dual-beam ion implanter will be introduced in detail.

Maintaining ecological flow and mitigating impacts on river health are among the core requirements for sustainable hydropower development. Designing specific operational modes to fit specific ecological conditions of rivers remains a key practical challenge for hydropower operation, especially in terms of balancing the various tradeoffs among multiple objectives in the context of coordinated operation of cascade hydropower plants. Taking the Yalong River, China as an example, this study develops a decision-making support model that can quantitatively analyse the tradeoffs between the hydro-energy generation and river ecosystem projection under different hydrological conditions. The model contains three main components – calculation of ecological flow, multi-objective optimal operation, and determination of optimal schemes. For the ecological flow determination, we propose a revised variable monthly flow method (RVMF), which incorporates variations of hydrological conditions, also combines the classification concept of the Tennant method. For these objectives, we consider cascade power generation, the assurance rate of cascade power generation, and the assurance rate of ecological flow. The preliminary application in the Yalong River case has shown that (1) with the increase in environmental flow requirements of the river, the cascade power generation has dropped significantly, and the most affected is the Jinping-II hydropower plant; (2) there are clear tradeoffs between the cascade power generation and the assurance rate of cascade power generation, and the cascade power generation and the assurance rate of cascade power generation under different riparian ecological conditions; and (3) being able to quantify those tradeoffs provides crucial scientific evidence for stakeholder dialogue and informed decision making for hydropower operation modes that can achieve the best desirable balances between power generation and river health conservation.

In this work, we analyze the regularizing property of the stochastic gradient descent for the efficient numerical solution of a class of nonlinear ill-posed inverse problems in Hilbert spaces. At each step of the iteration, the method randomly chooses one equation from the nonlinear system to obtain an unbiased stochastic estimate of the gradient, and then performs a descent step with the estimated gradient. It is a randomized version of the classical Landweber method for nonlinear inverse problems, and it is highly scalable to the problem size and holds significant potentials for solving large-scale inverse problems. Under the canonical tangential cone condition, we prove the regularizing property for a priori stopping rules, and then establish the convergence rates under suitable sourcewise condition and range invariance condition.

As a tipping bucket rain gauge, the HOBO Data Logging Rain Gauge RG3-M (RG3-M) has been widely used for the field precipitation observation owing to its superiority of independent power supply by a small portable battery. To quantify the measurement accuracy of the RG3-M gauge, a standard Manual Gauge (MG) and eight other models of tipping bucket rain gauges were installed at the Chuzhou hydrological experiment station of China. In this study, we first compared and investigated the accumulated mounts of 18 rainfall events of two RG3-M gauges benchmarked by the standard MG. Then, five typical rainfall events were chosen to further analyse the observed accuracy of the RG3-M gauge for different rainfall intensities at hourly temporal scale. Finally, the impacts of wind speed and rainfall intensity on the precipitation measurements of the RG3-M gauge were preliminarily explored. Results indicate that the RG3-M gauge measurement generally underestimates rainfall approximately −4% against the standard MG observation, but the maximum deviation even reaches −12.87%. In terms of the hourly rainfall process, the reliable measurement scope of the RG3-M gauge is ranging from 1.5 to 3 mm/h; however, it should be noted that the underestimation is rather significant at the higher rainfall rates (>6 mm/h). Last, it was found that rainfall intensity is a nonnegligible factor for influencing the measurement of the RG3-M gauge. But the windy effect seems to be insignificant in our experiments, which might be attributed to the similar exposure of the compared gauges.

Objectives Patient safety climate is associated with patient outcomes in hospitals around the world. A better understanding of how safety climate varies within and across hospitals will help identify improvement opportunities. We examined variations in safety climate by work area and job category in Chinese hospitals. Methods We administered the Chinese Hospital Survey on Patient Safety Climate in 2011 to workers in 6 hospitals in China, with completed surveys from 1464 (86% response). We calculated the percent positive response for survey items and dimensions among hospitals and compared this across work areas and job categories using general linear models. Results Overall, 68% of responses suggested the presence of a positive safety climate. The percent positive responses were highest for organizational learning (86.1%) and unit management support for safety (84.5%) and lowest for staffing (30.6%) and error reporting (44.5%). Workers in surgical units, intensive care units, operating rooms, and emergency departments were slightly more negative regarding overall safety climate than those in medical and ancillary units. Physicians reported worse perceptions than nurses or other hospital workers on all dimensions except for unit management support for safety and communication and peer support. Conclusions The perceived problem with staffing in Chinese hospitals was consistent with other studies. The lack of positive responses for error reporting may indicate a lack of awareness of the importance of learning from and reporting minor events and near misses. Variations within and across hospitals in safety climate suggest that improvement interventions should be tailored to individual units and professional groups.

In this study, we examined gene expression in order to identify genes that are differentially expressed between the hepatocytes of Sichuan White geese and Landes geese. We hypothesized that such genes may be involved in the different predispositions between these two species to develop hepatic steatosis. RNA was isolated from primary hepatocytes of the two species, and suppression subtractive hybridization was employed to screen for genes that showed differences in mRNA expression. We built and characterized two reciprocal cDNA libraries that were enriched in genes up-regulated in Landes geese or Sichuan White geese. Using dot blot analysis we identified 128 of 600 randomly selected sequences that demonstrated differential expression between the two species. Of these differentially expressed genes, 115 sequences shared high homology with 46 known genes and 13 sequences corresponded to eight novel expressed sequence tags (ESTs). Based on functional clustering, up and down-regulated genes were mostly related to lipid metabolism, nuclear mRNA splicing, enzyme activity and transcription control. The expression of 18 selected clones was further studied by quantitative PCR. The data showed that eight clones similar to the genes ACSL5, CTGF, CIDEA, PPARγ, PCK, GSTS1, RPS4X, and THBS1 had significantly higher expression levels in the hepatocytes of Landes geese. In contrast, seven clones similar to the genes ADH5, YBX1, ASAH1, UCB, AOPVLDL, SCD-1, and ELOVL-6 had significantly higher expression levels in the hepatocytes of Sichuan White geese.

The overaccumulation of triglycerides in hepatocytes induces hepatic steatosis; however, little is known about the mechanism of goose hepatic steatosis. The aim of this study was to define an experimental model of hepatocellular steatosis with TG overaccumulation and minimal cytotoxicity, using a mixture of various proportions of oleate and palmitate free fatty acids (FFAs) to induce fat-overloading, then using suppressive subtractive hybridization and a quantitative PCR approach to identify genes with higher or lower expression levels after the treatment of cells with FFA mixtures. Overall, 502 differentially expressed clones, representing 21 novel genes and 87 known genes, were detected by SSH. Based on functional clustering, up- and down-regulated genes were mostly related to carbohydrate and lipid metabolism, enzyme activity and signal transduction. The expression of 20 selected clones involved with carbohydrate and lipid metabolism pathways was further studied by quantitative PCR. The data indicated that six clones similar to the genes ChREBP, FoxO1, apoB, IHPK2, KIF1B, and FSP27, which participate in de novo synthesis of fatty acid and secretion of very low density lipoproteins, had significantly lower expression levels in the hepatocytes treated with FFA mixtures. Meanwhile, 13 clones similar to the genes DGAT-1, ACSL1, DHRS7, PPARα, L-FABP, DGAT-2, PCK, ACSL3, CPT-1, A-FABP, PPARβ, MAT, and ALDOB had significantly higher expression levels in the hepatocytes treated with FFA mixtures. These results suggest that several metabolic pathways are altered in goose hepatocytes, which may be useful for further research into the molecular mechanism of goose hepatic steatosis.