•In 2020, 9.6% of students were depressed, about twice as many as in previous years.•Sleep disturbances were an important aspect of depression during the pandemic.•Physical exercise and online ...communication were popular stress coping methods.
The coronavirus-19 (COVID-19) pandemic has resulted in substantial mental health problems. In addition to the fear of infection, prevention policies that result in isolation such as lockdowns or, in Japan, “self-restraint,” are associated with psychological symptoms. University students are vulnerable to emotional disorders because of the psychological challenges associated with the transition to adulthood. Therefore, we investigated changes in the mental health of university students before and during the COVID-19 pandemic.
We used data from depression screening conducted by the University of Tsukuba, Japan, during student health examinations. Students completed the Patient Health Questionnaire-9 (PHQ-9) and an open-ended question on stress self-coping.
In 2020, 9.6% of students were depressed, approximately twice as many as in previous years. The paired samples Wilcoxon test showed that PHQ-9 scores were significantly higher in 2020 than in 2019; the largest effect size was for sleep difficulties. Analysis of the open-ended responses for stress coping strategies showed that physical activity and online communication were most frequently used.
The 2020 survey was web-based, whereas the surveys in previous years were completed in person. Only approximately one-sixth of participants answered the open-ended question.
The percentage of students with mental health problems has doubled, and more attention to student mental health is needed. However, many students seem to be using appropriate coping measures. Education about best practices and raising awareness about establishing and maintaining sleep–wake rhythms may be useful.
•BP blends have fast combustion process at high temperature.•BP blends improve brake thermal efficiency of biodiesel.•Particle mass and number concentration could be reduced by pentanol ...addition.•Diameter of the primary particle is minimized by pentanol addition.•The addition of 10% pentanol is recommended as a suitable replacement ratio.
The combustion, gaseous and particulate emissions of a diesel engine fueled with biodiesel–pentanol (BP) blends were investigated under different engine loads. The results indicate that with the increased pentanol fraction, the start of combustion is delayed. All of the BP blends provide faster combustion than biodiesel and diesel fuel from CA10 to CA90. The faster combustion of BP blends leads to a higher BTE than that of biodiesel and diesel fuel in most cases. The particle mass and number concentrations are reduced by the addition of pentanol in biodiesel in most test conditions, due to the higher oxygen concentration for the fuel/air stoichiometry, longer ignition delay for fuel/air mixing, and lower viscosity for the improvement of atomization. The R(CO)OR′ group in biodiesel is less efficient in suppressing the soot precursor’s formation than the ROH group in pentanol. The diameter of the primary particles is reduced with the increased addition of pentanol. The particulate emission of BP10 have higher oxidation reactivity that that of BP20 and BP30. Base on this study, pentanol–biodiesel can be considered as an acceptable alternative fuel for diesel engines due to its improved combustion performance and reduced particulate emissions.
Phytoplankton is an important component of aquaculture ecosystem. The succession of dominant species often dominates the trend of phytoplankton community structure balances, which affects the healthy ...development of aquaculture. To comprehensively assess phytoplankton community succession and explore the major driving factors of this succession in the indoor industrial aquaculture system for Litopenaeus vannamei, a combination of the traditional morphological analysis and high-throughput sequencing were used in the present study. A total of 9 phyla were detected by both methods. Bacillariophyta, Chlorophyta and Cyanophyta were the dominant groups. During the whole process of aquaculture, the succession of phytoplankton community composition in the flowing waters did not follow a clearly regular trend, and ammonia-N and DIN/DIP were the main driving factors. In the aquaculture waters, the dominant species of phytoplankton changed from Thalassiosira to Actinocyclus and Picochlorum. The increase in salinity and decrease in silicate-SiO2 concentrations were the main factors that drive this temporal succession. Some picophytoplankton (≤2 μm) and small nanophytoplankton (>2 μm and ≤ 10 μm) were detected by high-throughput sequencing but not observed by morphological analysis. Picophytoplankton represented 22.22% of total phytoplankton sequence abundance, and small nanophytoplankton accounted for 27.45% of total phytoplankton.
•Phytoplankton community was revealed by both morphological analysis and high-throughput sequencing.•The dominant species changed from Thalassiosira to Actinocyclus and Picochlorum.•Salinity and silicate were the main factors that drive this temporal succession.
Abstract
The phylogeny of the family Tritoniidae has recently been studied with significant advances, but the relationships between genera are still controversial. In our study, we investigated the ...phylogeny of Tritoniidae using the most diverse taxon sampling possible. We applied an integrative approach based on new sequences of two mitochondrial genes (COI and 16S), a nuclear gene (H3) and morpho-anatomical characters. The monophyly of the family Tritoniidae was not recovered in our phylogenetic analyses. In view of our results, we propose a new rearrangement at the subfamily and genus levels. The plate-bearing genera are raised to the subfamily level as the monophyletic Marioniinae subfam. nov., formed by Marionia and the reinstated Marioniopsis. The remaining plate-less genera are raised to the subfamily level as the monophyletic Tritoniinae Lamarck, 1809. The genus Myrella is reinstated to assign the Antarctic and sub-Antarctic tritoniids. The taxonomic status of the monotypic Tritonidoxa is confirmed. Species delimitation analyses reveal a new large Marionia species from the Gulf of Cádiz (south-west Spain, Atlantic Ocean) and evidence for the pseudocryptic speciation of numerous Atlantic–Mediterranean and Indo-Pacific tritoniids. Finally, taxonomic notes are provided for several species according to the proposed rearrangement.
As an important part of Taoist culture, "Lingbao Taoist music" is widely used in all kinds of Taoist rituals and ceremonies and is integrated into an organic whole. The Taoist scriptural rhythms that ...we collectively regard as "music" have a set of names and a classification system of their own within Taoism. Here, the question is obvious: when did these paradigms, formats, and norms of chanting behavior begin? In the longitudinal view, Taoist sutra rhymes have evolved and been lost in the process of historical development; horizontally, it is explored how it is related to other phenomena in traditional Chinese culture and how it has become the situation observed in reality. This paper takes "Taoist Jingyun" as the research object analyzes and researches it from the aspects of religious origin, historical evolution, and morphological analysis, and then peeps into the religious function and cultural connotation of Taoist Jingyun.
•Analysis of circular product design from a strategy implementation perspective.•Six key process factors and 47 factor conditions are presented in a framework.•Alignment of corporate sustainability ...maturity with VR strategy implementation.•Framework provides management support to implement circular product design.
Although recent circular economy literature has emphasized the strategic role played by circular product design in private sector organizations, strategic management literature has so far overlooked the management implications of integrating circular economy strategies into new or existing products. As a result, the implementation of circular product design in private sector organizations remains unclear. The present paper aims to describe the managerial factors necessary for the implementation of value retention strategies during design and to designate a range of conditions under which each factor may arise. Examples of implementation processes (n = 24) were collected via expert interviews and compiled within a comprehensive framework based on general morphological analysis. Hence, implementation processes are represented as a combination of a limited number of process conditions. The framework is also used to describe a taxonomy of process configurations using hierarchical clustering, which indicates a strong influence of corporate sustainability maturity profiles in the implementation configurations observed. The contents of the present work help bridge the gap between strategic management and circular product design literature by providing the building blocks necessary for the integration of value-retention strategies during product planning and development.
The increased availability of mapped environmental data calls for better tools to analyze the spatial characteristics and information contained in those maps. Publicly available, user-friendly and ...universal tools are needed to foster the interdisciplinary development and application of methodologies for the extraction of image object information properties contained in digital raster maps. That is the overarching goal of GuidosToolbox, which is a set of customized, thematically grouped raster image analysis methodologies provided in a graphical user interface and for all popular operating systems. The Toolbox contains a wide selection of dedicated algorithms and tools, which are complemented by batch-processing and pre- and post-processing routines, all designed to objectively describe and quantify various spatial properties of image objects in digital raster data. While first developed for the analysis of remote sensing data in environmental applications, the Toolbox now provides a generic framework that is applicable to image analysis at any scale and for any kind of digital raster data.
•The heterogeneity of quality in ‘Orah’ mandarin fruit under different climatic regions was identified by multivariate indicators such as weight, total soluble solids, malic acid and proline.•The ...result of principal component and factor analysis of vegetative and fruit characteristic showed that the dry-hot valley areas resulted in a highly efficient production of ‘Orah’ mandarin.•The meteorological characteristics of different climatic regions, in particular temperature and sunshine at the important developmental stages, reflect a considerable degree of variation in these indicators of ‘Orah’ mandarin.
There is little information on the impact of agrometeorological factors on late-maturing citrus varieties. Here, several indices of the agronomic and physiological quality of ‘Orah’ mandarin fruit during three consecutive years were studied along with the metabolic traits under different climatic conditions. The average yield was high in the dry-hot valleys. However, the yield and yield efficiency were the lowest in areas with humid-sparse sunlight. The fruit in the dry-hot valleys and south subtropical regions were large and had seed number beyond 15.38, while the fruit in areas with humid-sparse sunlight were reddish and had few seeds. A statistical analysis of the total soluble solids (TSS) within three years showed that the fruit with highest amounts were in the mid-subtropical regions (≥ 14.03%), followed by the dry-hot valleys. The fruit of tropical rainforest areas (titratable acid ≥ 0.67%) were considered to contain the highest percentage of acid. A metabolic analysis showed that the contents of several metabolites, such as malic acid and proline, varied noticeably across different climatic regions. Correlation and factor analyses of the agronomic, physiological and metabolic indices with meteorological parameters revealed that the fruit yield and quality in the dry-hot valleys were superior to those observed in other regions and that temperature, in particular at the degreening and overwintering stages, along with the hours of sunshine significantly resulted in a considerable degree of variation in the indicators of fruit heterogeneity, such as weight, TSS, malic acid and proline.
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•Block copolymers with various hydrophilic–hydrophobic chain lengths were synthesized.•Effects of the block chain lengths on the membranes’ properties were investigated.•Membranes’ ...physicochemical properties were found to be related to their morphologies.
Quaternary ammonium-functionalized poly(ether sulfone) (QA-PES) block copolymers with different block chain lengths were prepared as anion exchange membranes. Copolymers with similar hydrophilic/hydrophobic block ratios and hence similar IEC values, but with various oligomer block chain lengths were synthesized to investigate, for the first time, how the length of each oligomer included in the block copolymers affected the chemophysical and electrical properties of the obtained QA-PES anion exchange membranes. The copolymer with the optimal hydrophilic:hydrophobic block chain length (QA-PES-16-30) showed good phase separation. This led to the optimal formation of ionic clusters, and the highest ion conductivity of 81.01mScm−1 at 80°C, as well as excellent physicochemical stability even after alkaline treatment in 1M NaOH at 60°C for 500h, due to strengthening of the hydrophobic regions, strongly suggesting that the block chain length of each of the hydrophilic and hydrophobic blocks can affect the physicochemical properties of the polymer membranes. The H2/O2 single cell performance using the QA-PES-16-30 membrane showed a maximum power density of 260mWcm−2, much higher than that obtained from the Tokuyama A201.
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