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To explore the influence of surface energy on the contamination characteristics of insulators, COMSOL Multiphysics software was used to simulate the contamination characteristics of XWP 2-160 insulators under wind tunnel conditions, and the rationality of the modified expression of the dynamic deposition model of the contaminated particles was verified. The change of contamination characteristics before and after changing the surface energy of insulators under natural conditions was simulated and analyzed. The results show that under the original surface energy (72 mJ/m 2) and low surface energy (6.7 mJ/m 2) with the increase in particle size, the contamination amount of an insulator surface area decreases first and then increases. When the wind speed is 2 m/s, the change in the particle size has the most pronounced effect on the amount of contamination. The amounts of contamination for the low surface energy are 64–75%, 60–95%, 55–91% and 54–78% lower than those for the original surface energy for particle sizes of 10, 15, 20 and 25 μm, respectively. For the same wind speed, when the size of contamination particles increases, the difference between the ratio of DC and AC contamination accumulation is gradually increasing because of the influence of the electric field force. From the perspective of the insulator preparation process, the development of low surface energy insulators can improve their anti-fouling performance.

In response to the low threshing efficiency of millet ear petals, this study investigated the tensile and impact mechanical properties of millet petals during the millet threshing process. Jingu 21, Zhangza 16, and Changza 466 were used as experimental subjects to study the effects of tensile angle and growth part on fracture strength, and to determine the influence of impulse and growth part on drop and breakage rates. The results indicated that both growth part and tensile angle have a highly significant impact on the tensile fracture strength of the millet petals. The tensile fracture strength decreases with the increase in the tensile angle, and increases with the growth part from top to bottom. The variety, growth part, and impulse significantly affect the impact drop and breakage rates of the millet petals, with the main factors affecting the drop rate being impulse, variety, and growth part, in that order. When the impulse is 2.296 N·s, the threshing effect for Jingu 21 is optimal, with a drop rate of 65.091% and a breakage rate of 13.487%. This research provides theoretical insights into the simulation of the millet ear threshing process and the optimization of the performance of millet threshing equipment.

Optimizing the aerodynamic structure of composite insulators can guarantee the safe operation of power systems. In this study, we construct a simulation model for composite insulator contaminant deposition using the COMSOL simulation software, and the rationality of the simulation model and method is verified through wind tunnel experiments. Taking the FXBW4-110/100 composite insulator as an example, we adopt a progressive optimization plan to explore the impacts of shed spacing s, and shed inclination angles α and β on its contaminant deposition characteristics under DC and AC voltages. Based on the numerical simulation results, we analyze the antifouling performance of insulators before and after structural optimization. The results indicate the following: 1) The contaminant deposition of the insulator under AC and DC voltages is negatively correlated with the shed spacing s, but positively correlated with the lower inclination angle β. 2) Under AC voltages, the contaminant deposition of the insulator increases with the upper inclination angle α, while under DC voltages, the contaminant deposition shows an uptrend first, then a downtrend and then an uptrend again with the increase of the upper inclination angle α. 3) Compared with the original model, the AC-optimized model ( α = 6°, β = 2° and s = 98 mm) with a larger shed spacing s, and smaller shed inclination angles α and β showed superior antifouling performance at wind speeds of no less than 2 m/s, and under the typical conditions ( v = 2.5 m/s, d = 20 μm, and ρ = 2 200 kg/m 3), its contaminant deposition is 15% less than that of the original model ( α = 10°, β = 2° and s = 80 mm).

Abstract The severity of heat stroke (HS) is associated with intestinal injury, which is generally considered an essential issue for HS. Heat acclimation (HA) is considered the best strategy to protect against HS. In addition, HA has a protective effect on intestinal injuries caused by HS. Considering the essential role of gut microbes in intestinal structure and function, we decided to investigate the potential protective mechanism of HA in reducing intestinal injury caused by HS. HA model was established by male C57BL/6J mice (5–6 weeks old, 17–19 g) were exposed at (34 ± 0.7)°C for 4 weeks to establish an animal HA model. The protective effect of HA on intestinal barrier injury in HS was investigated by 16S rRNA gene sequencing and nontargeted liquid chromatography‐mass spectrometry (LC‐MS) metabolomics. According to the experimental results, HA can change the composition of the gut microbiota, which increases the proportion of lactobacilli, faecal bacteria, and urinobacteria but decreases the proportion of deoxycholic acid. Moreover, HA can reduce liver and kidney injury and systemic inflammation caused by HS and reduce intestinal injury by enhancing the integrity of the intestinal barrier. In addition, HA regulates inflammation by inhibiting NF‐κB signalling and increasing tight junction protein expression in HS mice. HA induces changes in the gut microbiota, which may enhance tight junction protein expression, thereby reducing intestinal inflammation, promoting bile acid metabolism, and ultimately maintaining the integrity of the intestinal barrier. In conclusion, HA induced changes in the gut microbiota. Among the gut microbiota, lactobacilli may play a key role in the potential protective mechanism of HA.

Abstract Aim To assess the effect of parental and peer support on children's self‐esteem during the isolation period in COVID‐19‐infected children is the main objective of this study. Design This is a descriptive cross‐sectional study. One hundred ninety children with a confirmed diagnosis of COVID‐19 were included. Methods A survey questionnaire to assess family and children's demographic characteristics was used for this study. A 13‐item scale to assess parental support during the isolation period and a 10‐item scale to assess peers' support during the isolation period were evaluated. Along with it, a 10‐item scale to assess self‐esteem during the isolation period was also measured. Results Home isolation was associated with higher parental and peer support scores than hospital isolation. The mean age of study participants was 13.23 ± 4.05 years; 52.6% were isolated at home versus 47.4% in hospital isolation. Phone calling and WhatsApp/messenger chat were methods of communication for 44.2% and 33.2% of patients, respectively. 6.3% of them had no method of communication. Child self‐esteem was significantly affected by both parental and peer support during isolation. The increase in pronounced negative psychological effects such as disorientation, anger, low self‐esteem and post‐traumatic distress may be caused by a lack of parental care. No patient or public contribution to this study Patients or the general public were not involved in the design, analysis or interpretation of the data in this study. The study's aim and objectives were developed based on children's self‐esteem, which was limited by questionnaire data information, so the researchers completed demographic and disease‐related questionnaires by interviewing them.

To address the issue of header loss in millet combine harvesters, a double-chain millet harvester header was designed based on the principles of contact mechanics and tribology. Key component parameters of the header were determined, with the divider length and width measuring 0.56 m and 0.30 m, respectively. The divider angle was 40°, and the spiral angle was also 40°. A prototype was manufactured, and field performance tests were conducted. The results showed that the total header loss rate of the double-chain header was lower than that of the single-chain header under various combinations of header height and harvesting speed. The lowest total header loss rate, 3.12%, occurred when the header height was 0.2 m and the harvesting speed was 1.667 m/s, with a grain loss rate of 0.55% and a spike loss rate of 2.57%. This research provides a theoretical foundation for the development of low-loss, high-efficiency millet combine harvesters.

Cellulose nanofibers (NF) were extracted from kapok fibers using TEMPO oxidation, followed by a combination of mechanical grinding and ultrasonic processing. The TEMPO-mediated oxidation significantly impacted the mechanical disintegration behavior of the kapok fibers, resulting in a high NF yield of 98%. This strategy not only improved the fibrillation efficiency but also reduced overall energy consumption during NF preparation. An ultralight and highly porous NF-based aerogel was successfully prepared using a simple ice-templating technique. It had a low density in the range of 3.5–11.2 mg cm−3, high compressional strength (160 kPa), and excellent thermal insulation performance (0.024 W m−1 K−1). After silane modification, the aerogel displayed an ultralow density of 7.9 mg cm−3, good hydrophobicity with a water contact angle of 128°, and excellent mechanical compressibility with a high recovery of 92% at 50% strain. Benefiting from the silene support structure, it showed a high oil absorptive capacity (up to 71.4 g/g for vacuum pump oil) and a remarkable oil recovery efficiency of 93% after being reused for 10 cycles. These results demonstrate that our strategy endows nanocellulose-based aerogels with rapid shape recovery and high liquid absorption capabilities.

Abstract Background The incidence of colorectal cancer (CRC) has increased in recent years. Identification of accurate tumor markers has become the focus of CRC research. Early and frequent DNA methylation tends to occur in cancer. Thus, identifying accurate methylation biomarkers would improve the efficacy of CRC treatment. Neuroglobin (NGB) is involved in neurological and oncological diseases. However, there are currently no reports on epigenetic regulation involvement of NGB in CRC. Results NGB was downregulated or silenced in majority CRC tissues and cell lines. The hypermethylation of NGB was detected in tumor tissue, but no or a very low methylation frequency in normal tissues. Overexpression of NGB induced G2/M phase arrest and apoptosis, suppressed proliferation, migration, invasion in vitro, and inhibited CRC tumor growth and angiogenesis in vivo. Isobaric tag for relative and absolute quantitation (Itraq)-based proteomics identified approximately 40% proteins related to cell–cell adhesion, invasion, and tumor vessel formation in the tumor microenvironment, among which GPR35 was proved critical for NGB-regulated tumor angiogenesis suppression in CRC. Conclusions NGB, an epigenetically silenced factor, inhibits metastasis through the GPR35 in CRC. It is expected to grow into a potential cancer risk assessment factor and a valuable biomarker for early diagnosis and prognosis assessment of CRC.

To determine the patterns and influencing factors of the mechanical properties of millet stems from different varieties during the maturity period, this study employed a complete block experiment method and conducted shearing and bending tests on millet stems using the INSTRON5544 electronic universal material testing machine. The research investigated the variation in the shear strength, specific shear energy, bending strength, elastic modulus, and bending stiffness at different internode positions of the stems of Changza 466, Zhangza 16, and Jingu 21 during their maturity period. The results indicated that the variety had a significant impact on the mechanical properties of millet stems: from largest to smallest, the order of shear and bending forces was Jingu 21, Zhangza 16, and Changza 466. The shear strength and bending strength of Jingu 21 were the greatest among the three stem samples. The internode position significantly affected the shear mechanical properties of the millet stems, showing a general trend of decreasing shear strength with ascending internode position. The effect of the internode position on the bending stiffness was highly significant, whereas its impact on the bending strength and elastic modulus was not significant. The shear strength of the millet stems ranged from 3.866 ± 1.086 to 6.953 ± 2.208 MPa, significantly lower than the bending strength, which ranged from 18.934 ± 4.374 to 34.286 ± 6.875 MPa. The lowest shear strength and specific shearing energy, recorded at the fifth internode, were 4.028 ± 1.918 MPa and 15.097 ± 12.633 MJ/mm2, respectively. Jingu 21 and Changza 466 exhibit better lodging resistance than Zhangza 16. It is recommended to use a cutting-type platform for harvesting millet stems, with the cutting height set at the fifth internode position. This study provides a theoretical basis for the design of millet harvesting machinery and the selection of harvest parameters.

Drug-induced gingival overgrowth (DIGO), induced by certain immunosuppressive drugs, antihypertensive agents, and antiepileptic drugs, may contribute to the formation of deeper periodontal pockets and intractableness in periodontitis. To date, multiple factors such as enhanced matrix production, inflammation, and reduced matrix degradation might be involved in the pathogenesis of DIGO. We have previously reported that SPOCK-1, a heparan sulfate proteoglycan, could affect gingival thickening by promoting epithelial-to-mesenchymal transition (EMT) in gingival keratinocytes. However, few studies have investigated whether a combination of these factors enhances the DIGO phenotype in animal models. Therefore, we investigated whether SPOCK-1, periodontal inflammation, and cyclosporin-A (CsA) could cooperatively promote gingival overgrowth. We first confirmed that Spock-1 overexpressing (Spock1-Tg) mice showed significantly thicker gingiva and greater alveolar bone loss than WT mice in response to ligature-induced experimental periodontitis. DIGO was induced by the combination of CsA administration and experimental periodontitis was significantly enhanced in Spock1-Tg mice compared to that in WT mice. Ligature-induced alveolar bone loss in CsA-treated Spock1-Tg mice was also significantly greater than that in CsA-treated WT mice, while being accompanied by an increase in Rankl and Col1a1 levels and a reduction in matrix metalloprotease expression. Lastly, SPOCK-1 promoted RANKL-induced osteoclast differentiation in both human peripheral blood mononuclear cells and murine macrophages, while peritoneal macrophages from Spock1-Tg mice showed less TNFα and IL-1β secretion than WT mice in response to Escherichia coli lipopolysaccharide. These results suggest that EMT, periodontal inflammation, and subsequent enhanced collagen production and reduced proteinase production contribute to CsA-induced DIGO pathogenesis.

Objective: Heatstroke (HS) is a severe acute disease related to gastrointestinal barrier dysfunction, systemic inflammation and multiple organ injury. Many of the functions of Intestinal alkaline phosphatase (IAP) have been linked to gut homeostasis, gut barrier function and inflammation. However, the protective effect of IAP on heatstroke is not fully elucidated. This study aims to explore the protective effect of IAP on heatstroke by maintaining intestinal barrier and improving permeability. Methods: Male C57BL/6 mice were placed in a controlled climate chamber (ambient temperature: 40.0 ± 0.5 °C; humidity: 60 ± 5 %) until the maximum core temperature (Tc, max) reached 42.7 °C (the received criterion of HS). Then heat exposed mice (n = 195) were divided into three groups: 0.2 mL of 0.9 % physiological saline (HS) or vehicle (HS + Vehicle) or 300 IU IAP (HS + IAP) by gavage at 0, 24, and 48 h after onset. Control group mice (Con) (n = 65) were not exposed to heat and were gavaged with 0.9 % physiological saline of the same volume at the same time. Results: IAP treatment significantly reduced the levels of endotoxin, FD4, and D-lactate in the blood of heatstroke mice, reduced intestinal permeability and maintained the integrity of the intestinal barrier by increasing the expression of tight junction proteins. Meanwhile, IAP treatment alleviated liver and kidney damage caused by heatstroke, reduced serum levels of inflammatory cytokines, and thus improved survival rate of mice after heatstroke. Conclusion: This study indicates that IAP can improve the intestinal barrier function and intestinal permeability by increasing intestinal tight junctions, reduce systemic inflammation and multiple organ injury and improving the survival rate of heatstroke. Therefore, we consider IAP may be added to enteral nutrition formulas as a potential means for diseases characterized by intestinal permeability disorders, including heatstroke.

Metamaterials as artificially structural materials exhibit customized properties unattainable in nature. While dynamic response is highly desired, metamaterials are usually passive and cannot be tuned post-fabrication. A conventional active metamaterial consists of rigid resonators mounted on flexible substrates that permit a limited amount of mechanical tuning. Given that rigid resonators permanently deform or debond under large strains (above 30%), the range of flexibility that is possible with tunable metamaterials is limited. Here, we propose a kirigami-inspired geometry that overcomes this limitation. The proposed design enhances stretchability exceeding 100% when compared with the existing design. A high degree of flexibility is achieved through “stress engineering” at the interface between rigid resonators and flexible substrates. Our design shows that the resonance modes shift at a rate of 3.32 ± 0.1 nm for every 1% change in strain, which is the highest tunability reported thus far. We demonstrate how this new concept can be applied to structural color. Using a single design, we demonstrated the full range of colors for the first time. The novel concept of highly stretchable metamaterials may revolutionize the field and enable its use in applications such as wearable sensors, smart displays, and switchable devices requiring extremely dynamic properties.

Abstract Background Top-soil microbiomes make a vital contribution to the Earth’s ecology and harbor an extraordinarily high biodiversity. They are also key players in many ecosystem services, particularly in arid regions of the globe such as the African continent. While several recent studies have documented patterns in global soil microbial ecology, these are largely biased towards widely studied regions and rely on models to interpolate the microbial diversity of other regions where there is low data coverage. This is the case for sub-Saharan Africa, where the number of regional microbial studies is very low in comparison to other continents. Results The aim of this study was to conduct an extensive biogeographical survey of sub-Saharan Africa’s top-soil microbiomes, with a specific focus on investigating the environmental drivers of microbial ecology across the region. In this study, we sampled 810 sample sites across 9 sub-Saharan African countries and used taxonomic barcoding to profile the microbial ecology of these regions. Our results showed that the sub-Saharan nations included in the study harbor qualitatively distinguishable soil microbiomes. In addition, using soil chemistry and climatic data extracted from the same sites, we demonstrated that the top-soil microbiome is shaped by a broad range of environmental factors, most notably pH, precipitation, and temperature. Through the use of structural equation modeling, we also developed a model to predict how soil microbial biodiversity in sub-Saharan Africa might be affected by future climate change scenarios. This model predicted that the soil microbial biodiversity of countries such as Kenya will be negatively affected by increased temperatures and decreased precipitation, while the fungal biodiversity of Benin will benefit from the increase in annual precipitation. Conclusion This study represents the most extensive biogeographical survey of sub-Saharan top-soil microbiomes to date. Importantly, this study has allowed us to identify countries in sub-Saharan Africa that might be particularly vulnerable to losses in soil microbial ecology and productivity due to climate change. Considering the reliance of many economies in the region on rain-fed agriculture, this study provides crucial information to support conservation efforts in the countries that will be most heavily impacted by climate change. Video Abstract