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Background Drought stress could suppress the carbon assimilation and limit nutrient uptake of pear plants, thus affecting their growth and severely impacting the quality and yield of pear fruit. ABA is a stress hormone and is reported to alleviate drought stress in numerous plants. However, whether and how ABA functions in the drought responses of pear plants is yet explored. Results Here, to address this gap, pear seedlings ( Pyrus betulaefolia ) were used and subjected to PEG-induced drought conditions with or without additional ABA in various doses. The results showed that while drought caused severe leaf water loss and damage, applying ABA at 50 µM and 100 µM dramatically amended the phenomenon, as indicated by the markedly increased relative water content, and notably decreased relative electrolyte leakage and malondialdehyde content. Based on the results of RNA sequencing and related physiological indices, it was found that drought grossly disrupted chlorophyll synthesis and photosynthesis. It induced the over-production of reactive oxygen species (ROS) and broke the ROS homeostasis, despite the pronounced increases in ABA biosynthesis/content and signaling, flavonoid synthesis, and antioxidant enzyme activities, as well as sugar metabolism. However, ABA applications significantly elevated the expressions of genes in chlorophyll synthesis and photosynthesis, partially boosting the SPAD and Fv / Fm values. In addition, ABA treatments further prominently accelerate the synthesis processes of ABA, flavonoids, and antioxidant enzymes by up-regulating the corresponding genes, resulting in endogenous ABA accumulation and enzymatic activity improvement, thereby expediting the ROS scavenging. Of course, the sugar metabolism pathway was also outstandingly enhanced to balance the growth and stress response of pear seedlings. Moreover, through WGCNA analysis, the core turquoise module associated with ABA-attenuated drought stress was identified, and a portion of key transcription factors (TFs) and some hub genes were characterized, particularly for ERF, WRKY, MYB, bHLH, NAC in TFs, and CSP , COR , and DHN in hub genes. Overall, our study reveals that exogenous ABA could help pear plants to efficiently scavenge drought-induced ROS by improving their photosynthesis capacity, ABA accumulation, sugar catabolism, enzymatic antioxidant system, etc. These results will provide a scientific basis and practical direction for utilizing ABA to mitigate the adverse effects of water starvation resulting from the persistent high temperature on pear plants in summer. Conclusion 50 µM and 100 µM ABA application ameliorated the drought damage in pear seedlings, and the working routes are associated with reinforcement in the photosystem, ABA biosynthesis and signaling, flavonoid accumulation, and sugar metabolism, as well as enzymatic activities in ROS scavenging. The relevant regulatory network is complex, primarily concerned with ERF, WRKY, MYB, bHLH, and NAC TFs, with a focus on the potential target genes named CSP , COR , and DHN .

Shells are by-products of oil production from Camellia oleifera which have not been harnessed effectively. The purpose of this research is to isolate flavonoid from shells of Camellia oleifera and evaluate its anti-inflammatory and analgesic effects. The flavonoid was identified as bimolecular kaempferol structure by UV, MS, 1H NMR and 13C NMR spectra, which is a new biflavonoid and first found in Camellia oleifera. It showed dose-dependent anti-inflammatory activity by carrageenin-induced paw oedema in rats and croton oil induced ear inflammation in mice, and analgesic activity by hot plate test and acetic acid induced writhing. The mechanism of anti-inflammation of biflavonoid is related to both bradykinin and prostaglandins synthesis inhibition. The biflavonoid showed both central and peripheral analgesic effects different from aspirin, inhibition of the synthesis or action of prostaglandins may contribute to analgesic effect of biflavonoid. The biflavonoid significantly decreased malonaldehyde (MDA) and increased superoxidase dismutase (SOD) and Glutathione peroxidase (GSH-Px) activity in serum (p < 0.01), revealed strong free radical scavenging activity in vivo. It indicates the biflavonoid can control inflammation and pain by eliminating free radical so as to inhibit the mediators and decrease the prostaglandins. The biflavonoid can be used as a prospective medicine for inflammation and pain.

Background The relationship between human gut microbiota and high-altitude hypoxia acclimatization remains highly controversial. This stems primarily from uncertainties regarding both the potential temporal changes in the microbiota under such conditions and the existence of any dominant or core bacteria that may assist in host acclimatization. Results To address these issues, and to control for variables commonly present in previous studies which significantly impact the results obtained, namely genetic background, ethnicity, lifestyle, and diet, we conducted a 108-day longitudinal study on the same cohort comprising 45 healthy Han adults who traveled from lowland Chongqing, 243 masl, to high-altitude plateau Lhasa, Xizang, 3658 masl, and back. Using shotgun metagenomic profiling, we study temporal changes in gut microbiota composition at different timepoints. The results show a significant reduction in the species and functional diversity of the gut microbiota, along with a marked increase in functional redundancy. These changes are primarily driven by the overgrowth of Blautia A , a genus that is also abundant in six independent Han cohorts with long-term duration in lower hypoxia environment in Shigatse, Xizang, at 4700 masl. Further animal experiments indicate that Blautia A -fed mice exhibit enhanced intestinal health and a better acclimatization phenotype to sustained hypoxic stress. Conclusions Our study underscores the importance of Blautia A species in the gut microbiota’s rapid response to high-altitude hypoxia and its potential role in maintaining intestinal health and aiding host adaptation to extreme environments, likely via anti-inflammation and intestinal barrier protection.

The adhesive contact behavior between an elastic cylinder and a transversely isotropic piezoelectric cylinder under a pair of external forces and a mismatch strain is studied in this paper. By using the non-slipping JKR model, the considered problem can be reduced to the coupling singular integral equations, which can be solved analytically with the analytical function theory. The explicit analytical solutions of stress field within the contact region are obtained. The relationships between the contact size and external stimuli are set up by the Griffith energy balance criterion. Our analyses indicate that the elastic-piezoelectric system can be composed of any type of piezoelectric materials to obtain the same adhesive contact behaviors. There exists an increasing range of the contact width when exerting the negative mismatch strain on the cylinders, which can be increased by decreasing the Young’s modulus and Poisson’s ratio of the elastic cylinder. Furthermore, we find that the Young’s modulus and Poisson’s ratio of the elastic cylinder have little effect on the pull-off process of the elastic-piezoelectric adhesion system. The results obtained from this paper may be helpful for the design of the micro-electro-mechanical systems (MEMS) devices involving isotropic elastic solids and piezoelectric materials.

The classical adhesive contact models belong to isothermal adhesion theories, where the effect of temperature on adhesion was neglected. However, a number of experimental results indicated that the adhesion behaviors can be significantly affected by temperature. In this paper, the two-dimensional non-slipping anisothermal adhesion behaviors between two orthotropic elastic cylinders are investigated within the framework of the Johnson–Kendall–Roberts theory. The stated problem is reduced to the coupled singular integral equations by virtue of the Fourier integral transform, which are solved analytically with the analytical function theory. The closed-form solutions for the stress fields in the presence of thermoelastic effect are obtained. The stable equilibrium state of contact system is determined by virtue of the Griffith energy balance. The effect of temperature difference on adhesion behaviors between orthotropic solids is discussed. It is found that the difference between the oscillatory and non-oscillatory solutions increases with increasing the degree of anisotropy of orthotropic materials. The oscillatory solution cannot be well approximated by the non-oscillatory solution for the orthotropic materials with relatively high anisotropy.

Abstract Formalin-fixed paraffin-embedded (FFPE) tissues are widely available specimens for clinical studies. However, RNA degradation in FFPE tissues often restricts their utility. In this study, we determined optimal FFPE preparation conditions, including tissue ischemia at 4°C (<48 h) or 25°C for a short time (0.5 h), 48-h fixation at 25°C and sampling from FFPE scrolls instead of sections. Notably, we observed an increase in intronic reads and a significant change in gene rank based on expression level in the FFPE as opposed to fresh-frozen (FF) samples. Additionally, we found that more reads were mapped to genes associated with chemical stimulus in FFPE samples. Furthermore, we demonstrated that more degraded genes in FFPE samples were enriched in genes with short transcripts and high free energy. Besides, we found 40 housekeeping genes exhibited stable expression in FF and FFPE samples across various tissues. Moreover, our study showed that FFPE samples yielded comparable results to FF samples in dimensionality reduction and pathway analyses between case and control samples. Our study established the optimal conditions for FFPE preparation and identified gene attributes associated with degradation, which would provide useful clues for the utility of FFPE tissues in clinical practice and research.

Hypomotility is a common symptom of gallstone disease, which is accompanied by a loss of interstitial Cajal-like cells (ICLCs) in the gallbladder. Ursodeoxycholic acid (UDCA) is widely used in treating gallstone disease, and has shown anti-apoptotic and anti-inflammatory effects apart from its ability to dissolve gallstones. In this study, we investigated the anti-apoptotic and anti-inflammatory effects of UDCA on ICLCs in guinea pigs with gallstones. Guinea pigs were fed a high-cholesterol diet for 8 weeks to induce the formation of gallstones. A group of animals was administered UDCA (50 mg·kg −1 ·d −1 , ig) simultaneously. At the end of 8 weeks, the animals were euthanized with anesthesia, cholecystectomy was performed immediately and gallbladder was collected for further analysis. We showed that in the model group the contractility of gallbladder muscle strips in response to both acetylcholine (ACh) and CCK-8 was severely impaired, which was significantly improved by UDCA administration. Furthermore, UDCA administration significantly reduced the apoptotic ratio of ICLCs, based on the observation of co-localization imaging of apoptotic cells and c-kit-positive cells. Western blotting analysis and real-time PCR results revealed that the TNF-α/Caspase8/Caspase3 pathway was suppressed in the UDCA-treated animals, confirming the anti-apoptotic effect of UDCA in the gallbladder. The H&E staining showed that UDCA administration significantly attenuated inflammatory cell infiltration in the gallbladder wall. In conclusion, UDCA can protect ICLCs in the gallbladder from undergoing apoptosis by inhibiting the TNF-α/Caspase8/caspase3 pathway.

Alkaline water electrolysis (AWE) for highly efficient hydrogen production requires a highly active cathode. In this work, the porous NiAlMo electrodes were prepared by plasma spraying of NiAlMo and Al powders with a dual-channel powder feeding strategy. The bilayer-structured electrode consisting of a NiAlMo bond coat and a NiAlMo-Al composite coating on the top was designed. Al particles in the composite coating were used as pore former. The effect of Al powder feeding off-set distance on the molten state of Al was examined for optimizing the pore structure. The activated NiAlMo-40Al/NiAlMo electrode exhibited an apparent porosity of 36.8% and a surface roughness of Ra 12.18 μm, with an overpotential of 34.22 mV at 10 mA cm −2 and a Tafel slope of 27.71 mV dec −1 , which was much lower than that of traditional NiAlMo electrodes. After a CP test for 10 h, the electrode remained intact and showed a stable overpotential of -0.34 V.

The Space Advanced Technology demonstration satellite (SATech-01), a mission for low-cost space science and new technology experiments, organized by Chinese Academy of Sciences (CAS), was successfully launched into a Sun-synchronous orbit at an altitude of ∼500 km on July 27, 2022, from the Jiuquan Satellite Launch Centre. Serving as an experimental platform for space science exploration and the demonstration of advanced common technologies in orbit, SATech-01 is equipped with 16 experimental payloads, including the solar upper transition region imager (SUTRI), the lobster eye imager for astronomy (LEIA), the high energy burst searcher (HEBS), and a High Precision Magnetic Field Measurement System based on a CPT Magnetometer (CPT). It also incorporates an imager with freeform optics, an integrated thermal imaging sensor, and a multi-functional integrated imager, etc. This paper provides an overview of SATech-01, including a technical description of the satellite and its scientific payloads, along with their on-orbit performance.

Abstract The enigmatic Chinese mountain cat, endemic to the Qinghai-Tibet Plateau, has a controversial taxonomic status, whether a true species or conspecific with the wildcat (Felis silvestris) and whether it may have contributed to the domestication of cats (F. s. catus) in Asia. Here, we sampled 270 domestic and wild cats across China, sequenced 51 nuclear genomes, 55 mitogenomes, and multi-locus regions from modern and museum specimens. Genome-wide phylogenies supported taxonomic classification of the Chinese mountain cat as wildcat subspecies, F. s. bieti. No involvement of F. s. bieti in cat domestication in East Asia was detected, confirming that domestic cats shared a single origin from the African wildcat (F. s. lybica). A complex hybridization scenario including ancient introgression from the Asiatic wildcat (F. s. ornata) to F. s. bieti, and contemporary gene flow between F. s. bieti and sympatric domestic cats in the Tibetan region, raises the prospect of disrupting the genetic integrity of F. s. bieti, an issue with profound conservation implications. Competing Interest Statement The authors have declared no competing interest.