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Upper protective seam mining has been widely applied in China, but the theory of long-distance multiple upper protective seam mining is not yet perfect. In order to investigate the overburden stress evolution law of repetitive mining of long-distance coal seam groups, an experimental
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Upper protective seam mining has been widely applied in China, but the theory of long-distance multiple upper protective seam mining is not yet perfect. In order to investigate the overburden stress evolution law of repetitive mining of long-distance coal seam groups, an experimental study was conducted to simulate similar materials under repeated mining conditions in the long-distance double upper protective layer in the background of Pingmei Group 8th coal mine. By analyzing the roof-collapse structure and the stress evolution law of different layers of the floor during the superposition mining, the pressure-relief range of the protective layer after the mining of the double upper protective layer was determined. The study results showed that: the pressure relief of the protective layer in the long-distance upper protective layer mining was a dynamic process. After the mining of Group D coal seam, the maximum impact depth of the bottom plate could reach 182 m, and the pressure-relief angle of the upper side of Group E coal seam was 65°, and the pressure-relief angle of the lower side was 75°. The distance behind the vertical projection of the working face of Group D was 42 m. The overlapping back mining would affect the stress distribution of Group F coal seam. The pressure-relief angle of the upper side of Group F coal seam was 88°, and the pressure-relief angle of the lower side was greater than 78°. The distance behind the vertical projection of the working face of Group E was less than 61 m. The superposition and staggered mining of double protective layers could expand the protective layer. Through the verification of the measurement of gas parameters on site, it can be seen from the results that it has a certain protection effect. The research results can enrich the theory of long-distance multiple upper protective layer mining, and provide theoretical guidance for long-distance Coal Seam Group Mining in Pingmei coal-mine area.
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Breast cancer therapies have made significant strides in improving survival for patients over the past decades. However, recurrence and drug resistance continue to challenge long-term recurrence-free and overall survival rates. Mounting evidence supports the cancer stem cell model in which the existence of
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Breast cancer therapies have made significant strides in improving survival for patients over the past decades. However, recurrence and drug resistance continue to challenge long-term recurrence-free and overall survival rates. Mounting evidence supports the cancer stem cell model in which the existence of a small population of breast cancer stem cells (BCSCs) within the tumor enables these cells to evade conventional therapies and repopulate the tumor, giving rise to more aggressive, recurrent tumors. Thus, successful breast cancer therapy would need to target these BCSCs, as well the tumor bulk cells. Since the Women’s Health Initiative study reported an increased risk of breast cancer with the use of conventional hormone replacement therapy in postmenopausal women, many have turned their attention to phytoestrogens as a natural alternative. Phytoestrogens are plant compounds that share structural similarities with human estrogens and can bind to the estrogen receptors to alter the endocrine responses. Recent studies have found that phytoestrogens can also target BCSCs and have the potential to complement conventional therapy eradicating BCSCs. This review summarized the latest findings of different phytoestrogens and their effect on BCSCs, along with their mechanisms of action, including selective estrogen receptor binding and inhibition of molecular pathways used by BCSCs. The latest results of phytoestrogens in clinical trials are also discussed to further evaluate the use of phytoestrogen in the treatment and prevention of breast cancer.
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Single-molecule techniques have shifted the paradigm of biological measurements from ensemble measurements to probing individual molecules and propelled a rapid revolution in related fields. Compared to ensemble measurements of biomolecules, single-molecule techniques provide a breadth of information with a high spatial and temporal
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Single-molecule techniques have shifted the paradigm of biological measurements from ensemble measurements to probing individual molecules and propelled a rapid revolution in related fields. Compared to ensemble measurements of biomolecules, single-molecule techniques provide a breadth of information with a high spatial and temporal resolution at the molecular level. Usually, optical and electrical methods are two commonly employed methods for probing single molecules, and some platforms even offer the integration of these two methods such as optofluidics. The recent spark in technological advancement and the tremendous leap in fabrication techniques, microfluidics, and integrated optofluidics are paving the way toward low cost, chip-scale, portable, and point-of-care diagnostic and single-molecule analysis tools. This review provides the fundamentals and overview of commonly employed single-molecule methods including optical methods, electrical methods, force-based methods, combinatorial integrated methods, etc. In most single-molecule experiments, the ability to manipulate and exercise precise control over individual molecules plays a vital role, which sometimes defines the capabilities and limits of the operation. This review discusses different manipulation techniques including sorting and trapping individual particles. An insight into the control of single molecules is provided that mainly discusses the recent development of electrical control over single molecules. Overall, this review is designed to provide the fundamentals and recent advancements in different single-molecule techniques and their applications, with a special focus on the detection, manipulation, and control of single molecules on chip-scale devices.
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With the increase in demand for more sustainable energy sources, recent researchers have been looking into harvesting energy spent by humans for various purposes. One of the available sources of such energy is exercise equipment. While a few products are available in the
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With the increase in demand for more sustainable energy sources, recent researchers have been looking into harvesting energy spent by humans for various purposes. One of the available sources of such energy is exercise equipment. While a few products are available in the market to harvest the power expended during an exercise session, these products are costly, and the cost may prohibit a day-to-day user from purchasing those. Motivated by this challenge, this paper describes a long-running research project that uses a static exercise bicycle to sustainably harvest human energy. A regenerative spin bike that uses the friction between a flywheel and a BaneBots wheel was designed and deployed. For the motor mount, two methods are investigated: linear preloading and rotary preloading. A commercially available indoor static bicycle is modified to incorporate the flywheel and the motor attachment. The generated electricity is converted to DC using a three-phase rectifier. A car charger is used for charging any devices attached to the setup. The resulting configuration is very effective in operating small electronic devices. This setup, which uses only off-the-shelf components, can be considered a replacement for its expensive custom-made counterparts.
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Under the background that the high penetration of renewable energy generation, which mainly consists of wind power, will have a significant impact on electric power systems due to the volatility and uncertainty of renewable energy, energy systems with gas–electric coupling and interconnections have
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Under the background that the high penetration of renewable energy generation, which mainly consists of wind power, will have a significant impact on electric power systems due to the volatility and uncertainty of renewable energy, energy systems with gas–electric coupling and interconnections have been widely studied to accommodate renewable energy generation. This paper proposes a two-stage chance-constrained coordinated operation model of an integrated gas–electric system and fully considers the uncertainty and high penetration of wind power. The Taylor series expansion method is used to linearize the Weymouth gas flow equation of a natural gas system and finally obtains a mixed integer linear programming model. Case studies show the effectiveness of the integrated energy system for peak shaving, valley filling, and promoting wind power accommodation. The proposed model ensures the consumption of wind power generation and also reduces the operation cost by about 0.7%.
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In manufacturing food powders, foam-mat drying provides a cost-effective alternative to traditional drying methods. This study aimed to select the foaming conditions which support the subsequent drying of Magenta leaves extract. In the initial stage, concentrations of egg albumin (5 to 15%) as
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In manufacturing food powders, foam-mat drying provides a cost-effective alternative to traditional drying methods. This study aimed to select the foaming conditions which support the subsequent drying of Magenta leaves extract. In the initial stage, concentrations of egg albumin (5 to 15%) as a foaming agent, xanthan gum as foam stabilizer (0.1 to 0.5%), and whipping time (2 to 8 min) were designed. Multiple regression analysis was applied to analyze the relationship between the dependent variables (expansion volume and foam density) and three independent variables as an indicator of foaming capacity and foam stability. The multiple response optimization was applied to optimize the foam density and volume expansion. The optimum foam density (0.25 g/mL) and foam volume expansion (298.12%) were obtained at the optimum egg albumin and xanthan gum concentrations, and whipping time at 12.21%, 0.24%, and 5.8 min, respectively, indicating a stable foam structure. Experimental moisture loss data are fitted for five selected drying models. The mathematical models were compared according to three statistical parameters, such as coefficient of determination (R2), chi-square (χ2), and root mean square error (RMSE). Among the five mathematical models tested with experimental data, the Page model could be applied to describe the foam-mat drying process of magenta leaves extract. The highest value of R2 (99.54%), the lowest value of χ2 (0.0007), and RMSE (0.0253) were observed for a air drying temperature of 60 °C. The effect of temperature on diffusion is described by the Arrhenius equation with an activation energy of 100.21 kJ/mol. Effective moisture diffusion values ranged from 2.27 × 10−10 to 6.71 × 10−10 m2/s as the temperature increased. The effect of drying conditions on anthocyanin changes of magenta leaves powder was compared. The results showed that the highest quality of the sample was observed when the sample was dried at 60 °C.
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The balance between cellular proliferation and apoptosis and the regulation of cell differentiation must be established to maintain tissue homeostasis. These cellular responses involve the kinase cascade-mediated Hippo pathway as a crucial regulator. Hence, Hippo pathway dysregulation is implicated in diverse diseases, including
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The balance between cellular proliferation and apoptosis and the regulation of cell differentiation must be established to maintain tissue homeostasis. These cellular responses involve the kinase cascade-mediated Hippo pathway as a crucial regulator. Hence, Hippo pathway dysregulation is implicated in diverse diseases, including cancer. O-GlcNAcylation is a non-canonical glycosylation that affects multiple signaling pathways through its interplay with phosphorylation in the nucleus and cytoplasm. An abnormal increase in the O-GlcNAcylation levels in various cancer cells is a potent factor in Hippo pathway dysregulation. Intriguingly, Hippo pathway dysregulation also disrupts O-GlcNAc homeostasis, leading to a persistent elevation of O-GlcNAcylation levels, which is potentially pathogenic in several diseases. Therefore, O-GlcNAcylation is gaining attention as a protein modification that regulates the Hippo pathway. This review presents a framework on how O-GlcNAcylation regulates the Hippo pathway and forms a self-perpetuating cycle with it. The pathological significance of this self-perpetuating cycle and clinical strategies for targeting O-GlcNAcylation that causes Hippo pathway dysregulation are also discussed.
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Colorectal cancer remains one of the leading prevalent cancers in the world and is the fourth most common cause of death from cancer. Unfortunately, the currently utilized chemotherapies fail in selectively targeting cancer cells and cause harm to healthy cells, which results in
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Colorectal cancer remains one of the leading prevalent cancers in the world and is the fourth most common cause of death from cancer. Unfortunately, the currently utilized chemotherapies fail in selectively targeting cancer cells and cause harm to healthy cells, which results in profound side effects. Researchers are focused on developing anti-cancer targeted medications, which is essential to making them safer, more effective, and more selective and to maximizing their therapeutic benefits. Milk-derived extracellular vesicles (EVs) from camels and cows have attracted much attention as a natural substitute product that effectively suppresses a wide range of tumor cells. This review sheds light on the biogenesis, methods of isolation, characterization, and molecular composition of milk EVs as well as the therapeutic potentials of milk EVs on colorectal cancer.
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Only 20% of children worldwide reach the suggested physical activity (PA) levels, and the COVID-19 restrictions seemed to have worsened this situation. In addition, physical fitness (PF) is a crucial marker of health and combined with PA could predict future health status. The
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Only 20% of children worldwide reach the suggested physical activity (PA) levels, and the COVID-19 restrictions seemed to have worsened this situation. In addition, physical fitness (PF) is a crucial marker of health and combined with PA could predict future health status. The aim of this study was to compare reported PA and PF levels in a sample of Italian adolescents. We administered the International PA Questionnaire and International Fitness Enjoyment Scale to 208 adolescents aged 16.0 ± 1.5 (N = 166 females, 16 ± 2.0 years) recruited from a high school in the province of Milan (Italy). The majority of the subjects were “Minimally active” but reported adequate PF levels. In particular, subjects who reported a “Very good” PF perception, had a lower PA level. The misperception of reported PA and PF from our sample could reduce the future PA level in adolescents and lead to a negative spiral of disengagement in PA. These findings should lead to more attention on and improvements to PA promotion in the adolescent population after the restrictions caused by the COVID-19 pandemic.
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The extant research focused on gender understood as a single item to explain wishful identification and parasocial relationships with TV characters. This study focused on gendered personality traits and how they contribute to wishful identification, parasocial relationships with (non-)stereotypical male and female characters
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The extant research focused on gender understood as a single item to explain wishful identification and parasocial relationships with TV characters. This study focused on gendered personality traits and how they contribute to wishful identification, parasocial relationships with (non-)stereotypical male and female characters of the TV series Modern Family, and the series enjoyment in general. Participants (N = 508) were randomly assigned to one of four conditions with questions about either stereotypical male or female or non-stereotypical male or female characters. Respondents also answered questions about their own gender traits (positive/negative feminine/masculine), wishful identification, parasocial friendship and love for the assigned character, and enjoyment of the series. Different gendered personality traits were associated with wishful identification, parasocial friendship, and love with different types of characters, as well as series enjoyment. Thus, we conclude that media characters should exhibit both stereotypical and non-stereotypical traits to reach a broad and diverse audience.
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The objective of the present research was to evaluate if and to what extent the encounter between different cultures in a context of globalization may have influenced the adherence to the Mediterranean diet (MD) in adolescents. The study comprised a structured questionnaire packet
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The objective of the present research was to evaluate if and to what extent the encounter between different cultures in a context of globalization may have influenced the adherence to the Mediterranean diet (MD) in adolescents. The study comprised a structured questionnaire packet that inquired about anthropometric data, demographic information and both dietary and lifestyle habits. The KIDMED questionnaire was used to evaluate the adherence to the MD. A total of 103 respondents, aged 10–24 years (39.8% born in Italy or first-generation immigrants from Mediterranean countries) were included in the study. The results showed the highest percentage of adolescents having a medium adherence to the MD (44.7%), without differences according to geographical area of origin. Furthermore, the study proved that a higher adherence to the MD was significantly associated with daily breakfast (p = 0.008) and the consumption of fruit and vegetables (p = 0.002 and p = 0.000, respectively). Volunteers representing some of the different cultures and geographical proveniences currently present in Italy were perfectly integrated regarding diet and lifestyle, aspects considered in this study. Our investigation suggests the existence of incorrect dietary habits. It is certainly necessary to implement public health policies targeting adolescents to promote healthier lifestyle choices; the nutritional patterns of the MD should be among these choices.
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The current paper uses comparable data to present an overview of home-based long-term care (LTC) for persons over 65 years of age in Europe. It aims to provide new insights to aid discussions on LTC policy convergence in three areas: the need for
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The current paper uses comparable data to present an overview of home-based long-term care (LTC) for persons over 65 years of age in Europe. It aims to provide new insights to aid discussions on LTC policy convergence in three areas: the need for services, the extent to which these needs are met and the means employed to do so. It uses data from wave 6 (2015) of the Survey of Health, Ageing and Retirement in Europe (SHARE). Four summary indicators are charted: (i) the care need: how many people need care; (ii) the care gap: the extent to which stated needs remain unmet; (iii) the care mix: how overall provision is divided into formal, informal or a mix of both; and (iv) care satisfaction based on stated preferences by recipients. Heterogeneity at individual level is explained by probit analyses, examining how individual factors (age, severity of need, gender, social networks, prosperity and others) combine with country group and country effects. Scatter plots are used to relate differences among countries to systemic variables, such as public expenditures. The key conclusions are that: (i) Once needs are defined in comparable terms, there remains a surprisingly large number of people across Europe whose needs are not addressed at all, what we call the care gap, especially among the younger group aged 65–80; this is evident everywhere and is not limited to any one type of system or group of countries; (ii) formal and informal care are both significant for the stability of an LTC provision system and for the well-being of care recipients; and (iii) recipients of care are especially sceptical about formal care, as they reward principally informal carers with whom they have personal relationships. The overwhelming finding is that the heterogeneity defies easy generalisations, whether these relate to individual characteristics or systemic effects. This (unexplained) heterogeneity is a challenge for researchers to explain, but it could also represent an untapped resource for policymakers to exploit.
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Silk fibroin has emerged as a leading biomaterial for biomedical applications. 3D printing has been successfully used for printing with silk fibroin, albeit in the form of a bioink, in direct-write 3D printers. However, in the form of bioinks, stability and mechanical attributes
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Silk fibroin has emerged as a leading biomaterial for biomedical applications. 3D printing has been successfully used for printing with silk fibroin, albeit in the form of a bioink, in direct-write 3D printers. However, in the form of bioinks, stability and mechanical attributes of silk are lost. An innovative alternative to producing 3D printed solid silk constructs is silk milled into powder for printing in a binder jetting printer. In this work, we focus on characteristics of silk powder to determine suitability for use in 3D printing. Two different silk powders are compared with hydroxyapatite powder, a known biomaterial for biomedical constructs. We have investigated powder size and shape by Camsizer X2 and Scanning Electron Microscope and bulk behaviour, dynamic flow behaviour, and shear behaviour by FT4 powder rheometer. Preliminary printing tests were conducted in an in-house custom-built printer designed for silk powder. It was found that silk powder has low flowability and stability. Therefore, to print solely out of silk powder, a 3D printer design will need sophisticated techniques to produce flow to ensure even distribution and consistent thickness of powder layers during the printing process. It was also found that high concentrations of formic acid (>75 to 99 wt.%) can fuse particles and therefore be used as a binder ink for 3D printing. The printer design challenges for silk powder are discussed.
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CNN-based image processing has been actively applied to histopathological analysis to detect and classify cancerous tumors automatically. However, CNN-based classifiers generally predict a label with overconfidence, which becomes a serious problem in the medical domain. The objective of this study is to propose
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CNN-based image processing has been actively applied to histopathological analysis to detect and classify cancerous tumors automatically. However, CNN-based classifiers generally predict a label with overconfidence, which becomes a serious problem in the medical domain. The objective of this study is to propose a new training method, called MixPatch, designed to improve a CNN-based classifier by specifically addressing the prediction uncertainty problem and examine its effectiveness in improving diagnosis performance in the context of histopathological image analysis. MixPatch generates and uses a new sub-training dataset, which consists of mixed-patches and their predefined ground-truth labels, for every single mini-batch. Mixed-patches are generated using a small size of clean patches confirmed by pathologists while their ground-truth labels are defined using a proportion-based soft labeling method. Our results obtained using a large histopathological image dataset shows that the proposed method performs better and alleviates overconfidence more effectively than any other method examined in the study. More specifically, our model showed 97.06% accuracy, an increase of 1.6% to 12.18%, while achieving 0.76% of expected calibration error, a decrease of 0.6% to 6.3%, over the other models. By specifically considering the mixed-region variation characteristics of histopathology images, MixPatch augments the extant mixed image methods for medical image analysis in which prediction uncertainty is a crucial issue. The proposed method provides a new way to systematically alleviate the overconfidence problem of CNN-based classifiers and improve their prediction accuracy, contributing toward more calibrated and reliable histopathology image analysis.
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As an indispensable grain crop, foxtail millet (Setaria italica L.) is becoming a functional food in China because of its abundant nutrients. However, low rainfall and uneven precipitation limit its growth and production, especially in northwest China. Understanding the root phenotypic characteristics
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As an indispensable grain crop, foxtail millet (Setaria italica L.) is becoming a functional food in China because of its abundant nutrients. However, low rainfall and uneven precipitation limit its growth and production, especially in northwest China. Understanding the root phenotypic characteristics of foxtail millet is critical for utilizing its root characteristics to breed new millet varieties with improved resource-use efficiency and better adaptation to harsh environments. The present study characterized the variability of the root morphological traits at the seedling stage of 65 millet genotypes selected from four ecological regions across seven provinces in China. The plants were assessed after 21 days of growth in the germination pouches, and 48 root and shoot traits were measured. The results showed a large variation among the genotypes in the growth and functional traits. Among the measured traits, root dry mass, maximal root length, root surface area, and root tissue density contributed the most to the principal components. Root surface area ratio and root volume ratio were significantly correlated with root length ratio, respectively, while root length density and root weight density were negatively correlated with root diameter (p < 0.01). Shoot dry mass, root number, root length, root dry mass, and total dry mass were closely correlated with each other. Root length and root surface area in each 5-cm sections decreased from the top to the bottom along the root system. Among the four ecological regions, genotypes from the early maturing area of northwest China had the greatest root length, shoot dry mass, root dry mass, and root density, while those from the early maturing area of northwest China generally had the largest root system, with about 2.2 times more root length and dry weight than those from the early maturing area of northeast China (the shortest root system). The genotypic variability in root traits and correlations among shoot and root traits form a basis for breeding new millet cultivars.
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Several pharmaceutical companies are nowadays considering the use of agri-food waste as alternative raw material for the extraction of bioactive compounds to include in nutraceuticals and food supplements. This recycling activity is encountering the support of authorities, which are alarmed by air, soil
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Several pharmaceutical companies are nowadays considering the use of agri-food waste as alternative raw material for the extraction of bioactive compounds to include in nutraceuticals and food supplements. This recycling activity is encountering the support of authorities, which are alarmed by air, soil and water pollution generated by agricultural waste disposal. Waste reuse has several economic advantages: (i) its low cost; (ii) its abundance; (iii) the high content of bioactive molecule (antioxidants, minerals, fibers, fatty acids); as well as (iv) the financial support received by governments eager to promote eco-compatible and pollution-reducing practices. While nutraceuticals produced from biowaste are becoming popular, products that have been risk-assessed in terms of safety are quite rare. This despite waste biomass, in virtue of its chemical complexity, could, in many cases, mine the overall safety of the final nutraceutical product. In this review, we summarize the scientific results published on genotoxicity risk-assessment of bioactive compounds extracted from agricultural waste. The review depicts a scenario where the risk-assessment of biowaste derived products is still scarcely diffuse, but when available, it confirms the safety of these products, and lets us envisage their future inclusion in the list of botanicals allowed for formulation intended for human consumption.
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Background: The coronavirus disease 2019 (COVID-19) pandemic has restricted people’s activities and necessitated the discontinuation of cardiac rehabilitation (CR) programs for outpatients. In our hospital, CR for outpatients had to be discontinued for 3 months. We investigated the influence of this discontinuation of
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Background: The coronavirus disease 2019 (COVID-19) pandemic has restricted people’s activities and necessitated the discontinuation of cardiac rehabilitation (CR) programs for outpatients. In our hospital, CR for outpatients had to be discontinued for 3 months. We investigated the influence of this discontinuation of CR on physical activity, body composition, and dietary intake in cardiovascular outpatients. Method: Seventy-eight outpatients who restarted CR were investigated. We measured body composition, balance test, stage of locomotive syndrome, and food frequency questionnaire (FFQ) results at restart and 3 months later. We also investigated the results of examination that were obtained before discontinuation. Results: With regard to baseline characteristics, the percentage of male was 62.7% (n = 49), and average age and body mass index were 74.1 ± 8.5 years and 24.9 ± 7.0 kg/m2, respectively. Stage of locomotive syndrome and the results of FFQ did not change significantly. The one-leg standing time with eyes open test significantly worsened at restart (p < 0.001) and significantly improved 3 months later (p = 0.007). With regard to body composition, all limb muscle masses were decreased at restart and decreased even further 3 months later. Conclusions: Discontinuation of CR influenced standing balance and limb muscle mass. While the restart of CR may improve a patient’s balance, more time is required for additional daily physical activities. The recent pandemic-related interruption of CR should inspire the development of alternatives that could ensure the continuity of CR in a future crisis.
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Hyper compressors are key facilities for producing the low-density polyethylene with discharge pressure up to 350 MPa. Such high pressure brings great challenges to the design of the hyper compressor in many aspects. In this paper, a 3D transient computational fluid dynamics (CFD)
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Hyper compressors are key facilities for producing the low-density polyethylene with discharge pressure up to 350 MPa. Such high pressure brings great challenges to the design of the hyper compressor in many aspects. In this paper, a 3D transient computational fluid dynamics (CFD) model with inlet and outlet pipelines is built to investigate the thermodynamic performance of a hyper compressor. To realize the interaction between the thermodynamic processes and the pressure pulsation through valve dynamics, the pressures across the valve surfaces were monitored to the dynamic equation of the poppet valve. Then, structured grids were generated for the flow domain inside the valve, and the entire numerical model was solved by a commercial code: ANSYS Fluent. Consequently, the p-V diagram, the valve motion and pressure pulsation could be acquired simultaneously. The results of the numerical model showed that the exponents of the expansion and compression processes were 5.12 and 13.22, which were much larger than the common compressor. The maximal pressure pulsations were 13.25% and 22.07%, which occurred in the suction and discharge chambers, respectively. Severe flutter happened during the opening process of the suction valve due to the high incompressibility of the ethylene.
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Wood encodes environmental information that can be recovered through the study of tree-ring width and wood anatomical variables such as lumen area or cell-wall thickness. Anatomical variables often provide a stronger hydroclimate signal than tree-ring width, but they show a low tree-to-tree coherence.
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Wood encodes environmental information that can be recovered through the study of tree-ring width and wood anatomical variables such as lumen area or cell-wall thickness. Anatomical variables often provide a stronger hydroclimate signal than tree-ring width, but they show a low tree-to-tree coherence. We investigate the sources of variation in tree-ring width, lumen area, and cell-wall thickness in three pine species inhabiting sites with contrasting climate conditions: Pinus lumholtzii in wet-summer northern Mexico, and Pinus halepensis and Pinus sylvestris in dry-summer north-eastern Spain. We quantified the amount of variance of these three variables explained by spring and summer water balance and how it varied among trees. Wood anatomical variables accounted for a larger inter-individual variability than tree-ring width data. Anatomical traits responded to hydroclimate more individualistically than tree-ring width. This individualistic response represents an important issue in long-term studies on wood anatomical characteristics. We emphasized the degree of variation among individuals of the same population, which has far-reaching implications for understanding tree species’ responses to climate change. Dendroclimatic and wood anatomical studies should focus on trees rather than on the mean population series.
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Transnational education is education delivered to students in a country other than the country in which the awarding institution is based. While the outbreak of COVID-19 has significantly affected higher education, transnational education has exhibited its resilience against the pandemic, and has been
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Transnational education is education delivered to students in a country other than the country in which the awarding institution is based. While the outbreak of COVID-19 has significantly affected higher education, transnational education has exhibited its resilience against the pandemic, and has been continuously expanding in China. In parallel with the golden opportunities for the expansion of transnational education in China after the pandemic, a series of challenges resulting from the transnational context needs to be taken into due consideration, and to be properly addressed. In this paper, the opportunities and challenges for the post-COVID-19 development of transnational education in China are systematically discussed, based on the transnational education delivery at a Sino-Foreign cooperative university. Following our observations on opportunities and challenges, several suggestions are proposed, to address the potential challenges for the stable post-COVID-19 development of transnational education in China.
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Pine wilt disease in Korea can be managed by reducing vector density through chemical application. To reduce the side effects from pesticides, effective natural enemies must be identified and used to reduce the vectors’ natural density. Sentinel logs were used to investigate a
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Pine wilt disease in Korea can be managed by reducing vector density through chemical application. To reduce the side effects from pesticides, effective natural enemies must be identified and used to reduce the vectors’ natural density. Sentinel logs were used to investigate a parasitoid wasp parasitic to Monochamus alternatus and Monochamus saltuarius, the vectors of Bursaphelenchus xylophilus, which causes this disease. During 2016–2017, the parasitoid wasps distributed in the Pinus densiflora and Pinus koraiensis forests were surveyed using sentinel logs at six different areas. An ectoparasitoid wasp Spathius verustus Chao of M. alternatus and M. saltuarius was identified. We showed for the first time that S. verustus was parasitic to M. alternatus in South Korea and to M. saltuarius worldwide. The parasitism rates were affected by region and session but not by the sentinel log height in the tree and the distances between the trap and forest edge locations. Studies also showed that S. verustus appeared to prefer M. alternatus to M. saltuarius as a host. This study unveiled the ecological details of S. verustus. Further research on various environmental factors such as regional differences, host density differences, and the degree of damage from the pine wilt disease is required to understand the effects of environmental or ecological factors on parasitism rates.
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Pulmonary hypertension (PH) associated with left heart disease (PH-LHD) is the most common form of PH and has significantly higher morbidity and mortality. We estimated the prevalence of PH-LHD on the follow-up echocardiography and the role of left atrial (LA) function in PH-LHD.
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Pulmonary hypertension (PH) associated with left heart disease (PH-LHD) is the most common form of PH and has significantly higher morbidity and mortality. We estimated the prevalence of PH-LHD on the follow-up echocardiography and the role of left atrial (LA) function in PH-LHD. From the STRATS-AHF registry composed of 4312 acute heart failure (HF) patients, we analyzed peak atrial longitudinal strain (PALS) in 1729 patients with follow-up echocardiographic examinations during mean 18.1 ± 13.5 months. PH was determined by the maximal velocity of tricuspid regurgitation (TR Vmax ≥ 3.4 m/s). Persistent PH was found in 373 patients (21.6%). The PH-LHD group was significantly older, and the prevalence of atrial fibrillation (AF), hypertension, diabetes, and heart failure with preserved ejection fraction were higher compared with the no PH-LHD group. Baseline left ventricular end-systolic volume and PALS were lower, and LA diameter, mitral E/E’ ratio, and TR Vmax were higher in the PH-LHD group. In the multivariate analysis, PALS (HR = 1.024, p = 0.040) was a significant variable after adjustment of LA diameter and mitral E/E’. A decreased PALS of <12.5% was the best cutoff value in the prediction of persistent PH-LHD (AUC = 0.594, sensitivity = 65.3%, specificity = 46.1%). PH-LHD was associated with increased HF hospitalization (HR = 2.344, p < 0.001) and mortality (HR = 2.015, p < 0.001) after adjusting for age and sex. In conclusion, persistent PH-LHD was found in 21.6% in the follow-up echocardiography and was associated with decreased PALS (<12.5%). PH-LHD persistence was associated with poor clinical outcomes. Thus, AHF patients with decreased PALS, especially <12.5%, should be followed with caution.
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As with the majority of chronic diseases having specific nutrition recommendations, in cystic fibrosis (CF), the emphasis placed on patients regarding their diet and ideal body weight status often increases the risk of developing disordered eating behaviors and by inference, eating disorders (EDs).
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As with the majority of chronic diseases having specific nutrition recommendations, in cystic fibrosis (CF), the emphasis placed on patients regarding their diet and ideal body weight status often increases the risk of developing disordered eating behaviors and by inference, eating disorders (EDs). Body weight appears to be an important concern for patients with CF, with many patients struggling to lose weight. Between sexes, women appear more preoccupied with dieting compared to men, but exhibit a better body image, mainly due to their preference for a lower weight. Several comorbidities appear to change these dynamics, and visibly apparent factors, including scars, ports, and tubes, and the need for supplementary oxygen supply, may also influence body image perception. Disordered eating is usually initiated during a bout of pulmonary infection, with the patient feeling unwell to eat. Regarding the prevalence of EDs, research appears conflicting on whether it is higher among individuals with a CF diagnosis or not. As for comorbidities, anxiety and depression consist of the most common psychiatric diagnoses in CF, also greatly prevalent in EDs. Despite the plethora of studies, non-specific CF tools, small samples, and lack of data regarding important outcomes, including lung health, indicate the need for more research.
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The development of therapies to prevent or treat salivary gland dysfunction has been limited by a lack of functional in vitro models. Specifically, critical markers of salivary gland secretory phenotype downregulate rapidly ex vivo. Here, we utilize a salivary gland tissue chip model
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The development of therapies to prevent or treat salivary gland dysfunction has been limited by a lack of functional in vitro models. Specifically, critical markers of salivary gland secretory phenotype downregulate rapidly ex vivo. Here, we utilize a salivary gland tissue chip model to conduct a design of experiments (DoE) approach to test combinations of seven soluble cues that were previously shown to maintain or improve salivary gland cell function. This approach uses statistical techniques to improve efficiency and accuracy of combinations of factors. The DoE-designed culture conditions improve markers of salivary gland function. Data show that the EGFR inhibitor, EKI-785, maintains relative mRNA expression of Mist1, a key acinar cell transcription factor, while FGF10 and neurturin promote mRNA expression of Aqp5 and Tmem16a, channel proteins involved in secretion. Mist1 mRNA expression correlates with increased secretory function, including calcium signaling and mucin (PAS-AB) staining. Overall, this study demonstrates that media conditions can be efficiently optimized to support secretory function in vitro using a DoE approach.
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Modern coating methods have become an important part of industrial practice. For some materials and operations, the use of abrasion-resistant and hard coatings is an absolute necessity; for others, they are the key to greater efficiency and productivity. The aim of this work
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Modern coating methods have become an important part of industrial practice. For some materials and operations, the use of abrasion-resistant and hard coatings is an absolute necessity; for others, they are the key to greater efficiency and productivity. The aim of this work was to apply and subsequently analyze a new type of thin coating micro-layers TiAlN and TiAlCN, applied using HIPIMS coating technology from a physical point of view. In particular, chemical composition (EDS) and microstructure analyses were carried out in the area of applied coatings. Prepared cross-sectional metallographic samples were evaluated using electron microscopy. A detailed microstructural characterization of the individual elements was carried out on the lamellae of the investigated sample using transmission electron microscopy. It was found that this new multilayer micro-coating based on TiAlN + TiAlCN at a thickness of 5.8 µm increases the repeatability of production strokes by 200%. This finding was confirmed by testing the production of cartridges in the real operation of a large manufacturing company.
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