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Memristors with nonstoichiometric tungsten oxide (WO x) as an active layer, derived from the oxidation of atomically thin two-dimensional tungsten diselenide (WSe 2), enable the creation of the monolithic layered structure of WO x /WSe 2. These devices are promising candidates for emulating various biological synaptic functions in the human brain. In this study, we fabricate monolithic few-layer WO x /WSe 2 memristors with precisely controlled WO x thickness by UV-ozone treatment from 1 L to 9 L, depending on chuck temperature. The postsynaptic responses of the topmost single-layer (1 L) oxidized WSe 2 and fully (9 L) oxidized WSe 2 memristors exhibit sharply contrasting behaviors, which can be applied to mimic the heterosynaptic plasticity in the CA1 region of the hippocampus. Beyond the significance of emulating the biological synaptic characteristics, we explore the feasibility of using each oxidation-layer-controlled memristor as a hardware accelerator. Their performances are assessed through application in a CIFAR-10 pattern recognition task using a convolutional neural network. Pattern recognition rates of 84 % and 71 % are obtained for the 1 L and 9 L WO x -based devices, respectively. We also examine the applicability of a synaptic cell composed of devices with oppositely switched characteristics. Consequently, the synaptic weight—defined as the difference in conductance between two synaptic devices—can be either increased (potentiated) or decreased (depressed) by simultaneously updating both devices with the same voltage signal. This weight update concept achieves a moderate recognition rate of 85.94 % when using an MNIST pattern-based recognition task, simplifying the complex weight-adjustment process. [Display omitted] • Precisely controllable oxidation of WSe 2 by UV-ozone oxidation • Observation of opposite synaptic behaviors by modulating thickness of the oxide layer • Potential for mimicking heterosynaptic plasticity with oppositely behaved memristors • Simplified weight update process achieves a recognition rate of 85.94 % [ABSTRACT FROM AUTHOR]

The purpose of this phenomenological study is to understand mothers' lived pregnancy experiences during the COVID-19 pandemic. A qualitative, phenomenological study Participants completed the demographic survey online and semi-structured interviews, via video conferencing between November and December 2021 A sample of 28 mothers who were pregnant during the COVID-19 pandemic participated in the study. An inductive, thematic approach was used to analyze the data. Two central themes and eight subthemes emerged from the six-phase thematic analysis. The first central theme, Depth of Knowledge About COVID-19 , included the following subthemes: 1) Vaccines and 2) Uncertainty for Exposure. The second central theme, Impacts of COVID-19 , had six subthemes: 1) Types of Support Received , 2) COVID-19 Restrictions , 3) Childcare , 4) Mental Health , 5) Spending More Time at Home, and 6) Isolation. Findings of this study revealed mothers experienced a significant amount of stress and anxiety related to the coronavirus pandemic during their pregnancy. Our findings highlight the need to provide pregnant mothers comprehensive care, including mental health services, adequate access to social support, and providing clear information regarding COVID-19 vaccination and its impacts on pregnancy. [ABSTRACT FROM AUTHOR]

• Development of conceptual framework for sustainable diets that is locally relevant. • Utilized participatory workshop, expert interviews, and characterized datasets. • Framework includes 235 unique, measurable indicators within eight domains. • Minimum metrics for each domain can inform sustainable diets policies and progress. • Key leverage points include food safety, chemical usage, food waste, and water. A major barrier to achieving sustainable diets is the lack of clearly defined and agreed upon intervention points that will positively influence multiple sectors of the food system. There is an urgent need to understand what policy approaches and interventions will most effectively enhance the sustainability of diets in rapidly urbanizing low- and middle-income countries. To address this need, this work combines the input of diverse stakeholders and analysis of existing datasets to develop a conceptual framework for sustainable diets that is locally relevant to Vietnam using a process that is generalizable to other developing countries. The resulting framework includes 235 unique, measurable indicators within eight domains: (1) food production, (2) food processing and distribution, (3) food loss and waste, (4) food access and consumption, (5) food and water safety, (6) nutrition, (7) sociopolitical context, and (8) environmental impact. This conceptual framework was employed in a participatory workshop that brought together 50 Vietnamese stakeholders from diverse areas of expertise to identify and prioritize specific metrics for measuring sustainable diets. Based on the results of the stakeholder workshop, expert interviews, and characterized datasets, a comprehensive set of minimum metrics for each domain was produced and key leverage points that are likely to have an impact across multiple sectors were identified. These leverage points include food quality and safety, agricultural chemical usage, food waste, and water management. The analysis is expected to contribute to evidence-based policymaking in Vietnam to cultivate more sustainable diets. [ABSTRACT FROM AUTHOR]