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Gut microbes thrive by utilising host energy and, in return, provide valuable benefits, akin to a symbiotic relationship. Here, metagenomic sequencing was performed to characterise and compare the community composition, diversity and antibiotic resistance of the gut microbiota of Relict gull (Larus [...] Read more.
Gut microbes thrive by utilising host energy and, in return, provide valuable benefits, akin to a symbiotic relationship. Here, metagenomic sequencing was performed to characterise and compare the community composition, diversity and antibiotic resistance of the gut microbiota of Relict gull (Larus relictus) and Anatidae species. Alpha diversity analysis revealed that the intestinal microbial richness of L. relictus was significantly lower than that of Anatidae, with distinct differences observed in microbial composition. Notably, the intestines of L. relictus harboured more pathogenic bacteria such as clostridium, which may contribute to the decline in their population and endangered status. A total of 117 strains of Escherichia coli were isolated, with 90.60% exhibiting full susceptibility to 21 antibiotics, while 25.3% exhibited significant biofilm formation. Comprehensive Antibiotic Resistance Database data indicated that glycopeptide resistance genes were the most prevalent type carried by migratory birds, alongside quinolone, tetracycline and lincosamide resistance genes. The abundance of resistance genes carried by migratory birds decreased over time. This metagenomic analysis provides valuable insights into the intestinal microbial composition of these wild bird species, offering important guidance for their conservation efforts, particularly for L. relictus, and contributing to our understanding of pathogen spread and antibiotic-resistant bacteria.
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Greg Lemke’s laboratory was one of the pioneers of research into the TAM family of receptor tyrosine kinases (RTKs). Not only was Tyro3 cloned in his laboratory, but his group also extensively studied mice knocked out for individual or various combinations of the
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Greg Lemke’s laboratory was one of the pioneers of research into the TAM family of receptor tyrosine kinases (RTKs). Not only was Tyro3 cloned in his laboratory, but his group also extensively studied mice knocked out for individual or various combinations of the TAM RTKs Tyro3, Axl, and Mertk. Here we primarily focus on one of the paralogs—MERTK. We provide a historical perspective on rodent models of loss of Mertk function and their association with retinal degeneration and blindness. We describe later studies employing mouse genetics and the generation of newer knockout models that point out incongruencies with the inference that loss of MERTK-dependent phagocytosis is sufficient for severe, early-onset photoreceptor degeneration in mice. This discussion is meant to raise awareness with regards to the limitations of the original Mertk knockout mouse model generated using 129 derived embryonic stem cells and carrying 129 derived alleles and the role of these alleles in modifying Mertk knockout phenotypes or even displaying Mertk-independent phenotypes. We also suggest molecular approaches that can further Greg Lemke’s scintillating legacy of dissecting the molecular functions of MERTK—a protein that has been described to function in phagocytosis as well as in the negative regulation of inflammation.
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Purushothaman Natarajan, Gayathri Delanerolle, Lucy Dobson, Cong Xu, Yutian Zeng, Xuan Yu, Kathleen Marston, Thuan Phan, Fiona Choi, Vanya Barzilova, Simon G. Powell, James Wyatt, Sian Taylor, Jian Qing Shi and Dharani K. Hapangama
Cancers2024, 16(10), 1860; https://doi.org/10.3390/cancers16101860 (registering DOI) - 13 May 2024
Background: Total hysterectomy with bilateral salpingo-oophorectomy via minimally invasive surgery (MIS) has emerged as the standard of care for early-stage endometrial cancer (EC). Prior systematic reviews and meta-analyses have focused on outcomes reported solely from randomised controlled trials (RCTs), overlooking valuable data
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Background: Total hysterectomy with bilateral salpingo-oophorectomy via minimally invasive surgery (MIS) has emerged as the standard of care for early-stage endometrial cancer (EC). Prior systematic reviews and meta-analyses have focused on outcomes reported solely from randomised controlled trials (RCTs), overlooking valuable data from non-randomised studies. This inaugural systematic review and network meta-analysis comprehensively compares clinical and oncological outcomes between MIS and open surgery for early-stage EC, incorporating evidence from randomised and non-randomised studies. Methods: This study was prospectively registered on PROSPERO (CRD42020186959). All original research of any experimental design reporting clinical and oncological outcomes of surgical treatment for endometrial cancer was included. Study selection was restricted to English-language peer-reviewed journal articles published 1 January 1995–31 December 2021. A Bayesian network meta-analysis was conducted. Results: A total of 99 studies were included in the network meta-analysis, comprising 181,716 women and 14 outcomes. Compared with open surgery, laparoscopic and robotic-assisted surgery demonstrated reduced blood loss and length of hospital stay but increased operating time. Compared with laparoscopic surgery, robotic-assisted surgery was associated with a significant reduction in ileus (OR = 0.40, 95% CrI: 0.17–0.87) and total intra-operative complications (OR = 0.38, 95% CrI: 0.17–0.75) as well as a higher disease-free survival (OR = 2.45, 95% CrI: 1.04–6.34). Conclusions: For treating early endometrial cancer, minimal-access surgery via robotic-assisted or laparoscopic techniques appears safer and more efficacious than open surgery. Robotic-assisted surgery is associated with fewer complications and favourable oncological outcomes.
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High-speed submerged marine vehicles, such as torpedoes, traveling at velocities of an order of 100 m/s and above, require powerful propulsion to overcome the tremendous hydrodynamic drag. This paper aims to investigate a marine hybrid-propellant water-breathing ram rocket (marine ramjet or ducted rocket)
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High-speed submerged marine vehicles, such as torpedoes, traveling at velocities of an order of 100 m/s and above, require powerful propulsion to overcome the tremendous hydrodynamic drag. This paper aims to investigate a marine hybrid-propellant water-breathing ram rocket (marine ramjet or ducted rocket) under various underwater cruise conditions. At high underwater cruise speeds, the ram rocket outperforms regular rocket motors, substantially increasing its specific impulse and thrust. This investigation utilized a unique test facility capable of dynamically testing the marine ramjet. Over 20 dynamic experiments have been conducted, revealing the submerged motor characteristics at different cruise speeds, water-to-propellant mass ratios, and oxidizer-to-fuel mass ratios, thereby creating a performance map of the marine ramjet. The results were compared with static firing data and theoretical calculations, showing a good agreement with standard specific impulse improvement of about 55% compared to a regular hybrid rocket, reaching a maximum value of 380 s. The significant increase in performance demonstrates the potential of the water-breathing ramjet for propelling high-speed underwater vehicles.
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Oil/water (O/W) emulsions were prepared using the complex of quarternized cellulose nanofiber (QCNF) and octanoyl gelatin (OC−Gel) as an emulsifier, and the effect of pH value on their stability was investigated. OC−Gel was prepared through a condensation reaction, confirmed by 1H Nuclear
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Oil/water (O/W) emulsions were prepared using the complex of quarternized cellulose nanofiber (QCNF) and octanoyl gelatin (OC−Gel) as an emulsifier, and the effect of pH value on their stability was investigated. OC−Gel was prepared through a condensation reaction, confirmed by 1H Nuclear Magnetic Resonance (NMR) and Fourier Transform Infrared (FT−IR) spectroscopy. It reduced air/water interfacial tension more effectively than unmodified gelatin. The complexation degree of OC−Gel and QCNF, measured by optical density, showed its maximum at a QCNF/OC−Gel mass ratio of 1/8 when the pH value of the medium was 7.4, and it increased in a saturated manner with increasing pH value. The signals of QCNF were found in the FT−IR and X−ray diffraction spectra of the complex, suggesting that the positively charged CNF were included in the OC−Gel−based complex. The complex formed a rough surface with smooth debris because the surface roughness of the complex aggregation reflected that of both QCNF and OC−Gel aggregation. QCNF could stabilize oil droplets to form a Pickering O/W emulsion. The complex of QCNF/OC−Gel was also a good emulsifier. QCNF and the complex were as potent as OC−Gel in emulsifying mineral oil in water. Most of the droplets fell within 5–25 µm, regardless of what the emulsifier was. The emulsion stabilized with OC−Gel increased in its oil droplet size more than two times in 20 days at all the pH vales tested (pH 3, 5, 7.4, 9), whereas the emulsion stabilized with QCNF remained almost constant in size during the same period regardless of the pH values. The droplet size of emulsion stabilized with the QCNF/OC−Gel complex did not change appreciably when the pH value was 5, 7.4, and 9. The complex seemed to act as a capsule wall and prevent the coalescence of the droplets. However, it increased dramatically due to the coalescence at pH 3, possibly because the complex could be dissolved under a strong acidic condition.
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Pervious planting concrete (PPC) is in line with the concept of ecological environmental protection. However, due to its own porous structure, it is difficult to obtain excellent mechanical properties and water permeability at the same time, which hinders its promotion and application. In
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Pervious planting concrete (PPC) is in line with the concept of ecological environmental protection. However, due to its own porous structure, it is difficult to obtain excellent mechanical properties and water permeability at the same time, which hinders its promotion and application. In this paper, natural gravel (NG), ordinary Portland cement (OPC), polyvinyl alcohol latex powder (PVAP) and polycarboxylate superplasticizer (PS) were used to prepare the PPC, and its mechanical properties and water permeability were studied. Three kinds of plants were planted in the PPC and their planting properties were studied. At the same time, the effect of Bacillus on the planting properties was studied. The results show that when the water–binder ratio (W/B) was 0.28 and the PVAP content was 0.8%, both the mechanical properties and water permeability of the PPC were optimal. The compressive strength and permeability coefficient were 14.2 MPa and 14.48 mm/s, respectively. The mechanical properties and water permeability of PPC prepared with 10~20 mm NG were better than those prepared with 5~10 mm NG. Among the three plants, the germination rate and growth of Elymus dahuricus Turcz (EDT) were the best. The incorporation of Bacillus can optimize its planting properties and promote the effective combination between plants and the PPC substrate.
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This study investigated the influence of high silicon (4.2 wt%) and varying aluminum (3.5–4.8 wt%) content on the high temperature oxidation behavior and thermophysical properties of SiMoAl vermicular graphite cast iron for hot-end exhaust components. Isothermal oxidation tests at 800 °C and nonisothermal
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This study investigated the influence of high silicon (4.2 wt%) and varying aluminum (3.5–4.8 wt%) content on the high temperature oxidation behavior and thermophysical properties of SiMoAl vermicular graphite cast iron for hot-end exhaust components. Isothermal oxidation tests at 800 °C and nonisothermal oxidation tests in a dry-air atmosphere were conducted on SiMo nodular iron, along with two SiMoAl vermicular graphite cast iron variants alloyed with 3.5 wt% Al and 4.8 wt% Al. The investigations revealed the formation of a thin duplex layer of oxide scale, consisting of an iron-rich external oxide layer and continuous aluminum oxide at the metal/oxide interface. Although aluminum oxide acted as a protective barrier by impeding the solid-state diffusion of oxygen, severe subsurface oxidation was observed due to the interconnected vermicular graphite covered by aluminum oxides after decarburization. Furthermore, based on nonisothermal oxidation experiments, the effective activation energy of oxidation was found to be significantly increased by the addition of aluminum, even though the oxidation activation energies of SiMoAl samples exhibited small changes in comparison to each other. Additionally, thermophysical analysis demonstrated a substantial decrease in the thermal conductivity and a slight increase in the thermal expansion with the addition of aluminum.
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As climate change accelerates, urban areas are becoming increasingly inhospitable, with rising heat island effects and overall unhealthy environmental conditions. In this context, historic villages, due to their proximity to nature and lower population density, can represent a valuable alternative to unsustainable urban
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As climate change accelerates, urban areas are becoming increasingly inhospitable, with rising heat island effects and overall unhealthy environmental conditions. In this context, historic villages, due to their proximity to nature and lower population density, can represent a valuable alternative to unsustainable urban areas, providing better quality of life (i.e., through healthier environment, better work–life balance). They are “populated” by historic buildings characterized by high cultural value but are often in a state of abandonment. Nowadays, the adaptive reuse of cultural heritage represents an efficient strategy to adapt it to new needs/requirements and, at the same time, to preserve its historical and intrinsic values for present and future generations. In this framework, this study proposes a multidimensional evaluation framework for assessing cultural heritage adaptive reuse projects, covering all sustainability dimensions and capturing both tangible and intangible values. This framework, consisting of multiple criteria and multidimensional indicators, has been applied to evaluate alternative scenarios related to the regeneration of the abandoned Seminary in Sant’Agata de’ Goti (historic village), Benevento, Italy. In particular, three different scenarios have been evaluated by the SOCRATES (SOcial multi Criteria Assessment of European policies) method, a multicriteria decision method developed by the Joint Research Center (JRC) of the European Commission.
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Carbon dots (CDs), owing to their excellent photoluminescent features, have been extensively studied for physics preparation methods and for biomedical and optoelectronic device applications. The assessment of the applicability of CDs in the production of luminescent polymeric composites used in LEDs, displays, sensors,
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Carbon dots (CDs), owing to their excellent photoluminescent features, have been extensively studied for physics preparation methods and for biomedical and optoelectronic device applications. The assessment of the applicability of CDs in the production of luminescent polymeric composites used in LEDs, displays, sensors, and wearable devices is being pursued. The present study reports on an original, environmentally friendly, and low-cost route for the production of carbon dots with an average size of 4 nm by laser ablation in liquid. Jointly, to prove the significance of the study for a wide range of applications, a free-standing flexible polyvinyl alcohol (PVA) composite containing photoluminescent carbon dots was manufactured. CDs were prepared using targets of porose charcoal with a density of 0.271 g/cm3 placed in phosphate-buffered saline (PBS) liquid solution and irradiated for 30 min by pulsed IR diode laser. The optical properties of the obtained suspension containing carbon dots were studied with UV-ViS and FTIR spectroscopies. The photoluminescence of the produced carbon dots was confirmed by the emission peak at 480 nm in the luminescence spectrum. A narrow luminescence band with a full width at half-maximum (FWHM) of less than 40 nm could be an asset in spectral emission analysis in different applications. Atomic force microscopy confirms the feasibility of manufacturing CDs in clean and biocompatible environments, paving the way for an easier and faster production route, crucial for their wider applicability.
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The co-evolution between supermassive black holes and their environment is most directly traced by the hot atmospheres of dark matter halos. The cooling of the hot atmosphere supplies the central regions with fresh gas, igniting active galactic nuclei (AGN) with long duty cycles.
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The co-evolution between supermassive black holes and their environment is most directly traced by the hot atmospheres of dark matter halos. The cooling of the hot atmosphere supplies the central regions with fresh gas, igniting active galactic nuclei (AGN) with long duty cycles. The outflows from the central engine tightly couple with the surrounding gaseous medium and provide the dominant heating source, preventing runaway cooling. Every major modern hydrodynamical simulation suite now includes a prescription for AGN feedback to reproduce the realistic populations of galaxies. However, the mechanisms governing the feeding/feedback cycle between the central black holes and their surrounding galaxies and halos are still poorly understood. Galaxy groups are uniquely suited to constrain the mechanisms governing the cooling–heating balance, as the energy supplied by the central AGN can exceed the gravitational binding energy of halo gas particles. Here, we provide a brief overview of our knowledge of the impact of AGN on the hot atmospheres of galaxy groups, with a specific focus on the thermodynamic profiles of the groups. We then present our on-going efforts to improve on the implementation of AGN feedback in galaxy evolution models by providing precise measurements of the properties of galaxy groups. We introduce the XMM-Newton Group AGN Project (X-GAP), a large program on XMM-Newton targeting a sample of 49 galaxy groups out to .
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Subarachnoid hemorrhage (SAH) is a type of stroke caused by bleeding into the subarachnoid space. SAH is a medical emergency and requires prompt treatment to prevent complications such as seizures, stroke, or other brain damage. Treatment options may include surgery, medication, or a
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Subarachnoid hemorrhage (SAH) is a type of stroke caused by bleeding into the subarachnoid space. SAH is a medical emergency and requires prompt treatment to prevent complications such as seizures, stroke, or other brain damage. Treatment options may include surgery, medication, or a combination of both. 2-Cyano-3,12-dioxoolean-1,9-dien-28-oic acid (CDDO), a compound with anti-inflammatory and antioxidant properties, is currently being investigated as a potential treatment for various diseases, including chronic kidney disease and pulmonary arterial hypertension. In this study, the effects of CDDO on rats subjected to SAH were evaluated. Male Sprague-Dawley rats were divided into four groups (n = 6/group): (1) control group, (2) SAH group, (3) SAH + low-dose CDDO (10 mg/kg injected into the subarachnoid space at 24 h after SAH) group, and (4) SAH + high-dose CDDO (20 mg/kg) group. CDDO improved SAH-induced poor neurological outcomes and reduced vasospasm in the basal artery following SAH. It also decreased the SAH-induced expression of proinflammatory cytokines such as TNF-α, IL-1β, and IL-6 in both the cerebrospinal fluid and serum samples as determined by ELISA. A Western blot analysis confirmed an increase in the p-NF-κB protein level after SAH, but it was significantly decreased with CDDO intervention. Immunofluorescence staining highlighted the proliferation of microglia and astrocytes as well as apoptosis of the neuronal cells after SAH, and treatment with CDDO markedly reduced the proliferation of these glial cells and apoptosis of the neuronal cells. The early administration of CDDO after SAH may effectively mitigate neuronal apoptosis and vasospasm by suppressing inflammation.
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Paul Cristian Călugăr, Teodora Emilia Coldea, Carmen-Rodica Pop, Laura Stan, Emese Gal, Floricuța Ranga, Mihaela Mihai, Simona Codruța Hegheș, Elisabeta-Irina Geană and Elena Mudura
Agronomy2024, 14(5), 1036; https://doi.org/10.3390/agronomy14051036 (registering DOI) - 13 May 2024
The cider market has been significantly expanding and gaining momentum in Eastern Europe. As such, the aim of this study was to obtain sparkling cider via the Champenoise method using two Romanian apple varieties (Topaz and Red Topaz) alongside the employment of two
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The cider market has been significantly expanding and gaining momentum in Eastern Europe. As such, the aim of this study was to obtain sparkling cider via the Champenoise method using two Romanian apple varieties (Topaz and Red Topaz) alongside the employment of two fermentations. Four yeast strains were used in the first fermentation, while encapsulated Saccharomyces cerevisiae was used in the second fermentation. The resulting cider was subjected to a comprehensive investigation to quantitatively determine the carbohydrates, organic acids, volatile and phenolic compounds, and amino acids from all the cider samples. A trained panel evaluated the sensory profile of the samples, and a chemometric analysis was used to interpret the data. Secondary fermentation increased the accumulation of malic acid and lactic acid, as well as the volatile profile complexity. The total polyphenol content in the sparkling cider samples increased by almost 20% in the S. cerevisiae sample and over 217% in the P. kluyveri + S. cerevisiae sample compared to the base cider. Additionally, studying the production and consumption trends of sparkling cider offers valuable insights for both producers and consumers. By understanding consumer preferences and refining production techniques, the industry can deliver higher-quality products that better align with market demands.
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Advancements in cell culturing techniques have allowed the development of three-dimensional (3D) cell culture models sourced directly from patients’ tissues and tumors, faithfully replicating the native tissue environment. These models provide a more clinically relevant platform for studying disease progression and treatment responses
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Advancements in cell culturing techniques have allowed the development of three-dimensional (3D) cell culture models sourced directly from patients’ tissues and tumors, faithfully replicating the native tissue environment. These models provide a more clinically relevant platform for studying disease progression and treatment responses compared to traditional two-dimensional (2D) models. Patient-derived organoids (PDOs) and patient-derived xenograft organoids (PDXOs) emerge as innovative 3D cancer models capable of accurately mimicking the tumor’s unique features, enhancing our understanding of tumor complexities, and predicting clinical outcomes. Triple-negative breast cancer (TNBC) poses significant clinical challenges due to its aggressive nature, propensity for early metastasis, and limited treatment options. TNBC PDOs and PDXOs have significantly contributed to the comprehension of TNBC, providing novel insights into its underlying mechanism and identifying potential therapeutic targets. This review explores the transformative role of various 3D cancer models in elucidating TNBC pathogenesis and guiding novel therapeutic strategies. It also provides an overview of diverse 3D cell culture models, derived from cell lines and tumors, highlighting their advantages and culturing challenges. Finally, it delves into live-cell imaging techniques, endpoint assays, and alternative cell culture media and methodologies, such as scaffold-free and scaffold-based systems, essential for advancing 3D cancer model research and development.
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Agota Barabas, Attila C. Nagy, Viktoria Pazmany, Anita K. Grestyak Molnarne, Agnes Nemeth, György Jona, Agnes Santha, Peter Takacs, Emil Toldy-Schedel and Renata Javorne Erdei
Children2024, 11(5), 589; https://doi.org/10.3390/children11050589 (registering DOI) - 13 May 2024
The health status of Hungary’s population is unfavorable, with significant differences in health indicators not only compared to the EU15 but also to the Visegrad countries. Unfavorable health indicators can be disproportionate and particularly affect vulnerable groups, such as people with disabilities. In
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The health status of Hungary’s population is unfavorable, with significant differences in health indicators not only compared to the EU15 but also to the Visegrad countries. Unfavorable health indicators can be disproportionate and particularly affect vulnerable groups, such as people with disabilities. In this study, we set out to compare the health behavior of disabled youth and youth with typical development in Hungary. We also aimed to compare the health behavior of adolescents in the Visegrad countries. The eating habits of both groups of young people we examined are unfavorable. Adolescents with disabilities experience a significantly higher rate of school stress than children with typical development in Hungary. The prevalence of somatic complaints and parameters of poor mental well-being are significantly higher in Hungary than in the other Visegrad countries. The results indicate that additional interventions are needed in Hungary and that differentiated, professional health promotion is needed for young people with disabilities. The researchers recommend extending the study to disabled adolescents living in Visegrad countries, on the basis of which an injury-specific health promotion methodology could be developed with international interprofessional cooperation.
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Ignacio Alejandro Mendoza-Martínez, Edmundo Marroquín-Tovar, Jorge Pablo Rivas-Díaz, Araceli Durand, Gustavo Enrique Sauri-Alpuche and Blanca Rosa Garcia-Rivera
COVID2024, 4(5), 605-636; https://doi.org/10.3390/covid4050041 (registering DOI) - 13 May 2024
Amid the backdrop of the COVID-19 pandemic, the living conditions of the population were dramatically altered, with social distancing measures and the looming threat to public health leaving a profound impact on people’s lives. This study aims to assess the influence of COVID-19
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Amid the backdrop of the COVID-19 pandemic, the living conditions of the population were dramatically altered, with social distancing measures and the looming threat to public health leaving a profound impact on people’s lives. This study aims to assess the influence of COVID-19 on subjective well-being and overall quality of life in Mexico. A structural model with latent variables was used. Data were extracted from the National Self-Reported Well-being Survey (SWLS) from October 2020 and January 2021, featuring a robust sample size of 3615 residents from urban areas in Mexico, all aged 18 and above. Findings revealed that around 38% of the variance in overall life satisfaction in October 2020 and January 2021 could be attributed to Personal well-being (0.231), Personal satisfaction (0.320), Satisfaction with the environment (0.076), and Negative emotional states (−0.116). In comparison, October 2019 to January 2020 saw a lower 20% explained variance, primarily associated with Personal well-being (0.184), Personal satisfaction (0.270), and Satisfaction with the environment (0.052). Reliability assessments, including Cronbach’s Alpha coefficients, Rho_a, and Composite Reliability, all surpassed 0.70 for each subscale. In addition, our study confirmed convergent validity, as the Average Variance Extracted (AVE) consistently exceeded 0.50 across all subscales, while the discriminant coefficient exceeded 0.70.
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In order to shorten the length of satellite thermal testing and reduce the cost of satellite development, a new method of satellite thermal testing using a heat sink to simulate space heating flow has been proposed. First, based on the characteristics of low-orbit
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In order to shorten the length of satellite thermal testing and reduce the cost of satellite development, a new method of satellite thermal testing using a heat sink to simulate space heating flow has been proposed. First, based on the characteristics of low-orbit satellites and the current research of thermal tests, the necessity of studying high-efficiency thermal test methods for satellites is expounded, and the advantages of the heat sink equivalent thermal tests compared to conventional tests are explained. Then, the principle of the heat sink equivalent thermal tests is described, the formula to calculate the heat sink temperature is given, and an error analysis of the formula is conducted. It is found that when the emissivity of the heat sink surface is greater than 0.9 and the ratio of the heat sink’s surface area to the satellite’s is greater than 10, the error of the heat sink equivalent tests should be within 1 °C. Next, the application of the heat sink equivalent thermal test is described using the Jilin−1 GF02F satellite as an example. Finally, the test results and the flight temperature of the GF02F satellite are acquired and analyzed. The results show that the error of the heat sink equivalent thermal test is 0.9 °C, the test time is shortened by one-third compared to traditional thermal tests, and the cost of the thermal test is reduced by more than 70%.
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There is an essential clinical need to develop rapid process scaffolds to repair bone defects. The current research presented the development of calcium zirconium silicate/polycaprolactone for bone tissue engineering utilising melt extrusion-based 3D printing. Calcium zirconium silicate (CZS) nanoparticles were added to polycaprolactone
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There is an essential clinical need to develop rapid process scaffolds to repair bone defects. The current research presented the development of calcium zirconium silicate/polycaprolactone for bone tissue engineering utilising melt extrusion-based 3D printing. Calcium zirconium silicate (CZS) nanoparticles were added to polycaprolactone (PCL) porous scaffolds to enhance their biological and mechanical properties, while the resulting properties were studied extensively. No significant difference was found in the melting point of the samples, while the crystallisation temperature points of the samples containing bioceramic increased from 36.1 to 40.2 °C. Thermal degradation commenced around 350 °C for all materials. According to our results, increasing the CZS content from 0 to 40 wt.% (PC40) in porous scaffolds (porosity about 55–62%) improved the compressive strength from 2.8 to 10.9 MPa. Furthermore, apatite formation ability in SBF solution increased significantly by enhancing the CZS percentage. According to MTT test results, the viability of MG63 cells improved remarkably (~29%) in PC40 compared to pure PCL. These findings suggest that a 3D-printed PCL/CZS composite scaffold can be fabricated successfully and shows great potential as an implantable material for bone tissue engineering applications.
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This paper aims to offer an interpretation of Ham Sok Hon’s views on the dynamic relationship between religion and politics. While considerable discussion has already taken place in the Korean academic community across various fields, including philosophy, theology, and political science, many of
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This paper aims to offer an interpretation of Ham Sok Hon’s views on the dynamic relationship between religion and politics. While considerable discussion has already taken place in the Korean academic community across various fields, including philosophy, theology, and political science, many of which propose ssial philosophy as the metaphysical foundation of his political thoughts, there still remains a need for a more systematic understanding of their relationship, which I argue is closely linked to his concept of jeonilhwa gwajeong (the process of unification/integration). By exploring Ham’s unique analysis, particularly in relation to the notion of ipcheseong (stereoscopic/multi-dimensional), this paper will underscore their shared roots and objectives across different spheres of life: one pertaining to salim (human affairs) seeking the pursuit of fairness and equality, and the other dealing with spirituality, aspiring to grasp the sublime aspects of human existence. Both religion and politics, as these movements are termed, are mutually dependent, with their culmination promising peace and harmony in historical reality. Through highlighting Ham’s integrated perspective on religion and politics, I will ultimately suggest a specific discourse—civil religion—as a theoretical framework to effectively unravels Ham’s viewpoints.
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Seed germination is a complex process that can be negatively affected by numerous stresses. Trichoderma spp. are known as effective biocontrol agents as well as plant growth and germination stimulators. However, understanding of the early interactions between seeds and Trichoderma spp. remains limited.
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Seed germination is a complex process that can be negatively affected by numerous stresses. Trichoderma spp. are known as effective biocontrol agents as well as plant growth and germination stimulators. However, understanding of the early interactions between seeds and Trichoderma spp. remains limited. In the present paper, Fourier-transform infrared spectroscopy (FTIR) and Raman spectroscopy were used to reveal the nature of tomato seed germination as stimulated by Trichoderma. A rapid response of tomato seeds to Trichoderma spp. was observed within 48 h on Murashige and Skoog medium (MS) substrate, preceding any physical contact. Raman analysis indicated that both Trichoderma species stimulated phenolic compound synthesis by triggering plant-specific responses in seed radicles. The impact of T. harzianum and T. brevicompactum on two tomato cultivars resulted in alterations to the middle lamella pectin, cellulose, and xyloglucan in the primary cell wall. The Raman spectra indicated increased xylan content in NA with T9 treatment as well as increased hemicelluloses in GZ with T4 treatment. Moreover, T4 treatment resulted in elevated conjugated aldehydes in lignin in GZ, whereas the trend was reversed in NA. Additionally, FTIR analysis revealed significant changes in total protein levels in Trichoderma spp.-treated tomato seed radicles, with simultaneous decreases in pectin and/or xyloglucan. Our results indicate that two complementary spectroscopic methods, FTIR and Raman spectroscopy, can give valuable information on rapid changes in the plant cell wall structure of tomato radicles during germination stimulated by Trichoderma spp.
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There is an issue in the building stock, especially in Europe, concerning energy efficiency and climate change adaptation. Due to insufficient thermal insulation and passive solutions, the majority of the existing buildings are not only ill-prepared for the negative effects of climate change,
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There is an issue in the building stock, especially in Europe, concerning energy efficiency and climate change adaptation. Due to insufficient thermal insulation and passive solutions, the majority of the existing buildings are not only ill-prepared for the negative effects of climate change, but they also contribute to higher energy consumption. The combination of smart materials and 4D printing for hygrothermal rehabilitation of building facades is the main topic of this review paper. The paper examines the application of smart materials in construction to overcome problems with moisture and heat transfer and other issues in the building envelope. It discusses numerous instances of this printing technology’s applications, such as particular responsive elements, identifies trends and draws attention to knowledge gaps in the field, and assesses environmental and economic impacts. The objective is to offer comparable data to aid in upcoming studies concerning the creation of 4D-printed building façade solutions. Additionally, the paper can be interpreted as a collaborative attempt to influence the direction of future hygrothermal building rehabilitation practices. It also aims to assist designers and other relevant parties in understanding the advantages, restrictions, and difficulties related to 4D printing and smart materials for the sustainable management of buildings.
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Electric vertical takeoff and landing (eVTOL) aircraft represent a crucial aviation technology to transform future transportation systems. The unique characteristics of eVTOL aircraft include reduced noise, low pollutant emission, efficient operating cost, and flexible maneuverability, which in the meantime pose critical challenges to
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Electric vertical takeoff and landing (eVTOL) aircraft represent a crucial aviation technology to transform future transportation systems. The unique characteristics of eVTOL aircraft include reduced noise, low pollutant emission, efficient operating cost, and flexible maneuverability, which in the meantime pose critical challenges to advanced power retention techniques. Thus, optimal takeoff trajectory design is essential due to immense power demands during eVTOL takeoffs. Conventional design optimizations, however, adopt high-fidelity simulation models in an iterative manner resulting in a computationally intensive mechanism. In this work, we implement a surrogate-enabled inverse mapping optimization architecture, i.e., directly predicting optimal designs from design requirements (including flight conditions and design constraints). A trained inverse mapping surrogate performs real-time optimal eVTOL takeoff trajectory predictions with no need for running optimizations; however, one training sample requires one design optimization in this inverse mapping setup. The excessive training cost of inverse mapping and the characteristics of optimal eVTOL takeoff trajectories necessitate the development of the regression generative adversarial network (regGAN) surrogate. We propose to further enhance regGAN predictive performance through the transfer learning (TL) technique, creating a scheme termed regGAN-TL. In particular, the proposed regGAN-TL scheme leverages the generative adversarial network (GAN) architecture consisting of a generator network and a discriminator network, with a combined loss of the mean squared error (MSE) and binary cross-entropy (BC) losses, for regression tasks. In this work, the generator employs design requirements as input and produces optimal takeoff trajectory profiles, while the discriminator differentiates the generated profiles and real optimal profiles in the training set. The combined loss facilitates the generator training in the dual aspects: the MSE loss targets minimum differences between generated profiles and training counterparts, while the BC loss drives the generated profiles to share analogous patterns with the training set. We demonstrated the utility of regGAN-TL on optimal takeoff trajectory designs for the Airbus Vahana and compared its performance against representative surrogates, including the multi-output Gaussian process, the conditional GAN, and the vanilla regGAN. Results showed that regGAN-TL reached the 99.5% generalization accuracy threshold with only 200 training samples while the best reference surrogate required 400 samples. The 50% reduction in training expense and reduced standard deviations of generalization accuracy achieved by regGAN-TL confirmed its outstanding predictive performance and broad engineering application potential.
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In this study, the hyperbaric (2 bar) laser chemical vapor deposition of TiC fibers grown under various percent pressures of hydrogen and ratios of ethylene and titanium tetrachloride (2:1 or 1:1) are reported. In the hydrogen-rich (85%) condition, sequential fiber depositions became stunted
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In this study, the hyperbaric (2 bar) laser chemical vapor deposition of TiC fibers grown under various percent pressures of hydrogen and ratios of ethylene and titanium tetrachloride (2:1 or 1:1) are reported. In the hydrogen-rich (85%) condition, sequential fiber depositions became stunted as a result of a loss of hydrogen, which served as a reducing agent for the metal halide as hydrogen evolved with the hydrocarbon gas in the reaction zone because of the Le Chatelier principle. For the hydrogen-lean (25%) condition, the intrinsic fiber growth rate was invariant, but gas phase nucleation resulted in the hydrocarbon forming carbon soot in the chamber which subsequently deposited and coated on the fibers. In the hydrogen-balanced composition (50%), the 2:1 precursor ratio resulted in inconsistent intrinsic growth rates which ranged from approximately 30 μm/s to 44 μm/s. However, for the hydrogen-balanced (50%) 1:1 condition, the intrinsic growth rate variation was reduced to approximately 12 μm/s. The differences in fiber uniformity, composition, and structure under these process conditions are discussed in terms of hydrogen’s ability to serve as a reducing agent, a fluid to transport heat from the deposition zone, and alter the structure of the fiber through thermophoresis.
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In this paper, we address scheduling methods for queue stabilization and appropriate power allocation techniques in downlink dense user-centric scalable cell-free multiple-input multiple-output (CF-MIMO) networks. Scheduling is performed by the central processing unit (CPU) scheduler using Lyapunov optimization for queue stabilization. In this
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In this paper, we address scheduling methods for queue stabilization and appropriate power allocation techniques in downlink dense user-centric scalable cell-free multiple-input multiple-output (CF-MIMO) networks. Scheduling is performed by the central processing unit (CPU) scheduler using Lyapunov optimization for queue stabilization. In this process, the drift-plus-penalty is utilized, and the control parameter V serves as the weighting factor for the penalty term. The control parameter V is fixed to achieve queue stabilization. We introduce the dynamic V method, which adaptively selects the control parameter V considering the current queue backlog, arrival rate, and effective rate. The dynamic V method allows flexible scheduling based on traffic conditions, demonstrating its advantages over fixed V scheduling methods. In cases where UEs scheduled with dynamic V exceed the number of antennas at the access point (AP), the semi-orthogonal user selection (SUS) algorithm is employed to reschedule UEs with favorable channel conditions and orthogonality. Dynamic V shows the best queue stabilization performance across all traffic conditions. It shows a 10% degraded throughput performance compared to V = 10,000. Max-min fairness (MMF), sum SE maximization, and fractional power allocation (FPA) are widely considered power allocation methods. However, the power allocation method proposed in this paper, combining FPA and queue-based FPA, achieves up to 60% better queue stabilization performance compared to MMF. It is suitable for systems requiring low latency.
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