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Abstract Microbial anaerobic oxidation of methane coupled to the reduction of Mn(IV)-oxides, typically MnO2, derived from continental weathering and riverine transport has been proposed as a globally important sink of methane. However, the potential role of hydrothermal Mn(IV) oxide-rich sediments as a methane sink, and the mechanisms of underpinning methane oxidation at high-temperature hydrothermal fields remain poorly understood. Here, we report the occurrence of almost pure rhodochrosite with extremely negative δ13CPDB values (as low as –76.4‰) in direct association with hausmannite formed through hydrothermal activity in the Late Triassic Heqing Mn deposit in Southern China. Based on detailed petrography and geochemistry, this rhodochrosite is interpreted as the result of the thermochemical oxidation of methane by hausmannite during early diagenesis. Given high hydrothermal Mn2+ and CH4 release coupled to low sulfate concentration observed in the Archean oceans, we propose that hydrothermal Mn(IV) oxides may have been effective methane sinks in Earth’s ancient oceans.

This paper investigates two novel polarization- and pattern-diversity glass dielectric resonator antennas (DRAs), both of which are for tri-band (2.4, 5.2, and 5.8 GHz) wireless fidelity (WiFi) applications. It also investigates what type of diversity antenna is most suitable for WiFi router applications by comparing the two DRAs, along with a new space-diversity glass DRA. These three diversity glass DRAs are also compared with a commercial space-diversity monopole pair to benchmark the performance of the glass DRA in WiFi router applications. In our polarization-diversity antenna, a double-port feeding scheme is developed to excite different DRA modes. The frequencies of the DRA modes are tuned by using a stepped DRA. For the pattern-diversity design, a stacked DRA is introduced to broaden the bandwidth for both the conical and broadside radiation modes. All three of the new diversity antennas were fabricated and measured to verify the simulations. In our experiment, the bit error rate (BER) of the three diversity glass antennas and the reference space-diversity monopole antenna was also measured, and the results are compared and discussed. It is found that the polarization-diversity omnidirectional DRA has the most stable BER among the three.

Myocardial ischemia/reperfusion (I/R) injury leads to high mortality and morbidity due to the incomplete understanding of the underlying mechanism and the consequent lack of effective therapy. The present study revealed and validated key candidate genes in relation to inflammation and apoptosis pathways underlying myocardial I/R injury. Cathepsin S was identified as the top hub protein based on the protein-protein interaction analysis, and, thus, its role during myocardial I/R injury was further investigated. Myocardial I/R in mice resulted in significantly increased levels of myocardial injury biomarkers (cardiac troponin I, lactic dehydrogenase, and creatinine kinase-MB) and inflammatory cytokines (interleukin-1β [IL-1β], IL-6, and tumor necrosis factor-α), elevated apoptosis rate, and upregulated protein expression of cleaved caspase-8, cleaved caspase-3, and cleaved poly ADP-ribose polymerase. These abovementioned changes were blocked by two different selective cathepsin S inhibitors, LY3000328 or MIV-247. Moreover, Kaplan-Meier survival plot showed that cathepsin S inhibition improved 21-day survival rate following myocardial I/R injury. This study demonstrated that the inhibition of cathepsin S alleviated myocardial I/R-induced injury by suppressing inflammation and apoptosis, which may be used in clinical applications of cardioprotection.

ObjectivesThe willingness of family members to take care of older relatives directly affects the quality of life of disabled older adults, so it is necessary to understand the status quo of willingness to care and its influencing factors. This has been extensively studied in other countries, but, it is rarely studied in China. Based on the theory of altruism, employing a unique sample from Shanghai, China in 2017 and 2022, we attempt to reveal the influencing factors of the care willingness of family caregivers during the transition period.MethodsTo measure caregiver burden and functional disability of the care recipient, we employ the Zarit Burden Interview (ZBI) and the Barthel Index, respectively. Then we utilized the ordinary least squares (OLS) methodology and estimated four regression models. Models 1, 2, and 3 examined the impact of the variables of the caregiver burden, responsibility and love, and the quality of the caregiver-caregiver recipient relationship, respectively, on family caregivers’ willingness to care. Model 4 was the full model. To testify whether the caregiver burden is likely to act as a mediator, path analysis was used, and the path was adjusted and verified.ResultsAccording to the survey, in Shanghai, only half of the caregivers had a very high care willingness to care for disabled older relatives, while nearly one-tenth of the caregivers had a low willingness. It was the caregiver burden rather than the functional disability of older adults that harms family caregivers’ willingness to care. Responsibility and caring out of love were positively related to care willingness. Relationship quality was the most important influencing factor, explaining 10.2% of the variance in care willingness. Path analysis demonstrated that responsibility, caring out of love, and relationship quality directly and through the mediation of caregiver burden indirectly affected care willingness.ConclusionOur results revealed that reciprocal altruism presented by the quality of the caregiver-care recipient relationship had a significantly positive impact on family caregivers’ willingness to care. In addition, the caregiver burden was found not only directly affected care willingness, but also acted as a mediator. To promote the perfection of laws and policies, comprehensive samples of different types of cities should be included and the measurement of key variables could be further improved in future studies.

The broad application prospect of the honeycomb structure wave absorber in industrial and civil fields makes researchers focus on studying its wave absorbing mechanism so as to optimize its structural design and improve its wave absorbing performance. Distinguishing from the equivalent circuit thinking to study the honeycomb structured absorber, a kind of symmetry operation is adopted in this paper for the honeycomb structured absorber from the electromagnetic wave propagation point of view. The reflection loss is assumed to be the result of the loss of the incident electromagnetic wave in the absorbing body and the superposition of multiple refractions, and the symmetry operation can separate the specific physical process of the refracted wave involved in the superposition. The separated electromagnetic wave vector superposition is compared with the simulated and experimental values to verify the correctness of the conjecture. The separation results show that the absorption properties are determined by the internal loss and the phase change caused by the surface structure, which is of positive significance for the optimization and design of honeycomb absorbers.

BackgroundHeat shock protein 70 (Hsp70) has been shown to exert cardioprotection. Intracellular calcium ([Ca2+]i) overload induced by p38 mitogen-activated protein kinase (p38 MAPK) activation contributes to cardiac ischemia/reperfusion (I/R) injury. However, whether Hsp70 interacts with p38 MAPK signaling is unclear. Therefore, this study investigated the regulation of p38 MAPK by Hsp70 in I/R-induced cardiac injury.MethodsNeonatal rat cardiomyocytes were subjected to oxygen-glucose deprivation for 6 h followed by 2 h reoxygenation (OGD/R), and rats underwent left anterior artery ligation for 30 min followed by 30 min of reperfusion. The p38 MAPK inhibitor (SB203580), Hsp70 inhibitor (Quercetin), and Hsp70 short hairpin RNA (shRNA) were used prior to OGD/R or I/R. Cell viability, lactate dehydrogenase (LDH) release, serum cardiac troponin I (cTnI), [Ca2+]i levels, cell apoptosis, myocardial infarct size, mRNA level of IL-1β and IL-6, and protein expression of Hsp70, phosphorylated p38 MAPK (p-p38 MAPK), sarcoplasmic/endoplasmic reticulum Ca2+-ATPase2 (SERCA2), phosphorylated signal transducer and activator of transcription3 (p-STAT3), and cleaved caspase3 were assessed.ResultsPretreatment with a p38 MAPK inhibitor, SB203580, significantly attenuated OGD/R-induced cell injury or I/R-induced myocardial injury, as evidenced by improved cell viability and lower LDH release, resulted in lower serum cTnI and myocardial infarct size, alleviation of [Ca2+]i overload and cell apoptosis, inhibition of IL-1β and IL-6, and modulation of protein expressions of p-p38 MAPK, SERCA2, p-STAT3, and cleaved-caspase3. Knockdown of Hsp70 by shRNA exacerbated OGD/R-induced cell injury, which was effectively abolished by SB203580. Moreover, inhibition of Hsp70 by quercetin enhanced I/R-induced myocardial injury, while SB203580 pretreatment reversed the harmful effects caused by quercetin.ConclusionsInhibition of Hsp70 aggravates [Ca2+]i overload, inflammation, and apoptosis through regulating p38 MAPK signaling during cardiac I/R injury, which may help provide novel insight into cardioprotective strategies.

The hyperspectral imaging technology has the feature of “image and spectrum in one”, which brings together the features of traditional imaging and spectroscopic techniques, and both image information and spectral information of the agricultural products could be obtained. Therefore, this technology can not only detect the external characteristics of objects by imaging technology, but also obtain the internal quality and food safety information of agricultural products by the spectral technology, including variety classification, physical and chemical index determination, fungal infection detection and pesticide residue detection, etc. Compared with traditional detection methods, hyperspectral imaging has been applied in the field of non-destructive testing of agricultural products due to its simple pretreatment, non-pollution and non- destructive characteristics in the detection process. This review started from the theoretical basis of hyperspectral imaging, and summarized its image acquisition and analysis methods, followed by expounding the research progress of hyperspectral imaging technology in the field of nondestructive testing of agricultural products in the past five years. This review could provide information on the classification and nutritional quality of agricultural products and food safety assessment methods to provide reference.