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A series of homogeneous granite specimens were prepared to investigate the Mode I fracture toughness (KIC) using the cracked chevron-notched Brazilian disk (CCNBD) method and semicircular three-point bending (NSCB) method recommended by the International Society for Rock Mechanics (ISRM). A combination of acoustic emission (AE) and digital image correlation (DIC) was utilized to monitor the crack propagation and analyze the fracture modes at various test stages. The results indicated that the average value of Mode I fracture toughness (KIC-) of the CCNBD specimen was approximately 10% higher than that of the NSCB specimen. The coefficient of variation in the NSCB test was small, which could provide more stable result of Mode I fracture roughness. Compared to the CCNBD test, the failure mode of NSCB specimens was mainly tensile damage with instantaneous damage during the experimental process. Furthermore, the failure process of the NSCB test was mainly controlled by tensile fractures, which exhibited instantaneous failure. The CCNBD test was first controlled by tensile fractures and then by shear fractures when the peak was reached, exhibiting progressive failure. The failure mode and the process may be the main factors controlling the difference between the results of the NSCB and CCNBD tests. This work helps select appropriate methods to measure the Mode I rock fracture toughness.

To facilitate temperature adjustments, the testicles are located outside the body cavity. In most mammals, the temperature of the testes is lower than the body temperature to ensure the normal progression of spermatogenesis. Rising temperatures affect spermatogenesis and eventually lead to a decline in male fertility or even infertility. However, the testes are composed of different cell types, including spermatogonial stem cells (SSCs), spermatocytes, spermatozoa, Leydig cells, and Sertoli cells, which have different cellular responses to heat stress. Recent studies have shown that using different drugs can relieve heat stress-induced reproductive damage by regulating different signaling pathways. Here, we review the mechanisms by which heat stress damages different cells in testes and possible treatments.

Background Recent studies have shown that ubiquitin‐mediated cell apoptosis can modulate protein interaction and involve in the progress of oocyte maturation and spermatogenesis. As one of the key regulators involved in ubiquitin signal, ubiquitin C‐terminal hydrolase L1 (UCHL1) is considered a molecular marker associated with spermatogonia stem cells. However, the function of UCHL1 was wildly reported to regulate various bioecological processes, such as Parkinson's disease, lung cancer, breast cancer and colon cancer, how UCHL1 affects the mammalian reproductive system remains an open question. Methods We identified papers through electronic searches of PubMed database from inception to July 2022. Results Here, we summarize the important function of UCHL1 in controlling mammalian oocyte development, regulating spermatogenesis and inhibiting polyspermy, and we posit the balance of UCHL1 was essential to maintaining reproductive cellular and tissue homeostasis. Conclusion This study considers the ‘double‐edged sword’ role of UCHL1 during gametogenesis and presents new insights into UCHL1 in germ cells. UCHL1 and mammalian gametogenesis. UCHL1 affects apoptosis‐related factors in mammalian gametogenesis and controls mammalian oocyte development, regulates spermatogenesis and inhibits polyspermy. It may also have other biological functions in the testis or ovary, such as anti‐inflammatory or antiviral.

The stability of rock masses is critically influenced by pre-existing cracks, yet the micro-mechanisms governing cracks evolution under varying crack geometries remain inadequately quantified. This work introduces a novel, rock-specific acoustic emission (AE) classification criterion for marble, established through integrated notched semi-circular bend (NSCB) and straight-notched Brazilian disc (SNBD) tests. The proposed criterion for both tensile cracks (AF > 40 RA + 30) and shear cracks (AF < 20 RA + 30) provides a quantitative and material-adapted method for real-time crack-type discrimination. Combining AE monitoring with stress intensity factor (SIF) analysis, 9 groups of uniaxial compression tests were conducted on marble specimens with crack inclinations (15°, 30°, 45°, 60°, 75°, 90°) and lengths (5 mm, 10 mm, 15 mm). The synchronous evolution of SIF and AE parameters across four loading stages validates the AE-based classification. The test results reveal that crack inclination governs the tensile-to-shear transition, while crack length accelerates damage accumulation. It is demonstrated that the coupled AE-SIF analysis captures micro-mechanical crack evolution and bridges microscopic fracture processes with macroscopic failure modes. This study offers a reliable framework for early warning of rock instability.

Background: Plenty of evidence has suggested that autophagy plays a crucial role in the biological processes of cancers. This study aimed to screen autophagy-related genes (ARGs) and establish a novel a scoring system for colorectal cancer (CRC). Methods: Autophagy-related genes sequencing data and the corresponding clinical data of CRC in The Cancer Genome Atlas were used as training data set. The GSE39582 data set from the Gene Expression Omnibus was used as validation set. An autophagy-related signature was developed in training set using univariate Cox analysis followed by stepwise multivariate Cox analysis and assessed in the validation set. Then we analyzed the function and pathways of ARGs using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Finally, a prognostic nomogram combining the autophagy-related risk score and clinicopathological characteristics was developed according to multivariate Cox analysis. Results: After univariate and multivariate analysis, 3 ARGs were used to construct autophagy-related signature. The KEGG pathway analyses showed several significantly enriched oncological signatures, such as p53 signaling pathway, apoptosis, human cytomegalovirus infection, platinum drug resistance, necroptosis, and ErbB signaling pathway. Patients were divided into high- and low-risk groups, and patients with high risk had significantly shorter overall survival (OS) than low-risk patients in both training set and validation set. Furthermore, the nomogram for predicting 3- and 5-year OS was established based on autophagy-based risk score and clinicopathologic factors. The area under the curve and calibration curves indicated that the nomogram showed well accuracy of prediction. Conclusions: Our proposed autophagy-based signature has important prognostic value and may provide a promising tool for the development of personalized therapy.

Background Depression is a recurrent and devastating mental disease that is highly prevalent worldwide. Prolonged exposure to stressful events or a stressful environment is detrimental to mental health. In recent years, an inflammatory hypothesis has been implicated in the pathogenesis of stress-induced depression. However, less attention has been given to the initial phases, when a series of stress reactions and immune responses are initiated. Peripheral CD4 + T cells have been reported as the major contributors to the occurrence of mental disorders. Chronic stress exposure-evoked release of cytokines can promote the differentiation of peripheral CD4 + cells into various phenotypes. Among them, Th17 cells have attracted much attention due to their high pathogenic potential in central nervous system (CNS) diseases. Thus, we intended to determine the crucial role of CD4 + Th17 cells in the development of specific subtypes of depression and unravel the underpinnings of their pathogenetic effect. Methods In the present research, a daily 6-h restraint stress paradigm was employed in rats for 28 successive days to mimic the repeated mild and predictable, but inevitable environmental stress in our daily lives. Then, depressive-like symptoms, brain–blood barrier (BBB) permeability, neuroinflammation, and the differentiation and functional changes of CD4 + cells were investigated. Results We noticed that restrained rats showed significant depressive-like symptoms, concomitant BBB disruption and neuroinflammation in the dorsal striatum (DS). We further observed a time-dependent increase in thymus- and spleen-derived naïve CD4 + T cells, as well as the aggregation of inflammatory Th17 cells in the DS during the period of chronic restraint stress (CRS) exposure. Moreover, increased Th17-derived cytokines in the brain can further impair the BBB integrity, thus allowing more immune cells and cytokines to gain easy access to the CNS. Our findings suggested that, through a complex cascade of events, peripheral immune responses were propagated to the CNS, and gradually exacerbated depressive-like symptoms. Furthermore, inhibiting the differentiation and function of CD4 + T cells with SR1001 in the early stages of CRS exposure ameliorated CRS-induced depressive-like behaviour and the inflammatory response. Conclusions Our data demonstrated that inflammatory Th17 cells were pivotal in accelerating the onset and exacerbation of depressive symptoms in CRS-exposed rats. This subtype of CD4 + T cells may be a promising therapeutic target for the early treatment of stress-induced depression.

Objectives As the coronavirus disease 2019 (COVID‐19) pandemic continues to spread worldwide, nucleic acid detection is a key step in controlling it. Psychological issues and job burnout of nurses working in nucleic acid sampling roles for long periods have become apparent. This study aimed to explore the effects of mindfulness decompression therapy on mental health and job burnout in front‐line nurses working in nucleic acid sampling during the pandemic. Methods Nucleic acid sampling frontline nurses who were positive for burnout on both the Symptom Checklist‐90 (SCL‐90) and the Maslach Burnout Inventory‐General Scale (MBI‐GS) were selected as the participants. Frontline nurses in the nucleic acid testing area who received routine psychological nursing intervention from June 2020 to April 2021 were used as the control group. Nurses who received both routine psychological nursing and mindfulness decompression therapy from May 2021 to December 2021 formed the “mindfulness” subject group. We compared the two groups' primary outcome measures of SCL‐90 and MBI‐GS scores. Results Before the intervention, there were no significant differences between the two groups in general data, SCL‐90 scores, and MBI‐GS scores. After the mindfulness decompression therapy, according to SCL‐90 and MBI‐GS scales, psychological distress and job burnout of nurses in the mindfulness group were significantly better than those in the control group. Conclusion Mindfulness decompression therapy can effectively improve mental health and relieve job burnout in frontline nurses in nucleic acid sampling areas, which is worthy of clinical application. Randomized controlled trials are still needed, however, to fully confirm the effects of mindfulness decompression therapy.

The existing treatment modalities for skin injuries mainly include dressings, negative-pressure wound treatment, autologous skin grafting, and high-pressure wound treatment. All of these therapies have limitations such as high time cost, the inability to remove inactivated tissue in a timely manner, surgical debridement, and oxygen toxicity. Mesenchymal stem cells have a unique self-renewal ability and wide differentiation potential, and they are one of the most promising stem cell types in cell therapy and have great application prospects in the field of regenerative medicine. Collagen exerts structural roles by promoting the molecular structure, shape, and mechanical properties of cells, and adding it to cell cultures can also promote cell proliferation and shorten the cell doubling time. The effects of collagen on MSCs were examined using Giemsa staining, EdU staining, and growth curves. Mice were subjected to allogeneic experiments and autologous experiments to reduce individual differences; all animals were separated into four groups. Neonatal skin sections were detected by HE staining, Masson staining, immunohistochemical staining, and immunofluorescence staining. We found that the MSCs pretreated with collagen accelerated the healing of skin wounds in mice and canines by promoting epidermal layer repair, collagen deposition, hair follicle angiogenesis, and an inflammatory response. Collagen promotes the secretion of the chemokines and growth factors associated with skin healing by MSCs, which positively influences skin healing. This study supports the treatment of skin injuries with MSCs cultured in medium with collagen added.

Ulcerative colitis (UC) is a relapsing and reoccurring inflammatory bowel disease. The treatment effect of Alhagi maurorum and stem cell extracts on UC remains unclear. The aim of the present study was to investigate the protective role of Alhagi maurorum combined with stem cell extract on the intestinal mucosal barrier in an intestinal inflammation mouse model. Sixty mice were randomly divided into a control group, model group, Alhagi group, MSC group, and MSC/Alhagi group. MSC and Alhagi extract were found to reduce the disease activity index (DAI) scores in mice with colitis, alleviate weight loss, improve intestinal inflammation in mice (p < 0.05), preserve the integrity of the ileal wall and increase the number of goblet cells and mucin in colon tissues. Little inflammatory cell infiltration was observed in the Alhagi, MSC, or MSC/Alhagi groups, and the degree of inflammation was significantly alleviated compared with that in the model group. The distribution of PCNA and TNF-alpha in the colonic tissues of the model group was more disperse than that in the normal group (p < 0.05), and the fluorescence intensity was lower. After MSC/Alhagi intervention, PCNA and TNF-alpha were distributed along the cellular membrane in the MSC/Alhagi group (p < 0.05). Compared with that in the normal control group, the intensity was slightly reduced, but it was still stronger than that in the model group. In conclusion, MSC/Alhagi can alleviate inflammatory reactions in mouse colonic tissue, possibly by strengthening the protective effect of the intestinal mucosal barrier.

Ferroptosis is a relatively novel form of regulated cell death that was discovered in 2012. With the increasing research related to the mechanisms of ferroptosis, previous studies have demonstrated that the inactive of the intracellular antioxidant system and iron overload can result in the accumulation of reactive oxygen species (ROS), which can ultimately cause lipid peroxidation in the various cell types of the body. ROS accumulation can cause sperm damage by attacking the plasma membrane and damaging DNA. Acute ferroptosis causes oxidative damage to sperm DNA and testicular oxidative stress, thereby causing male reproductive dysfunction. This review aims to discuss the metabolic network of ferroptosis, summarize and analyze the relationship between male reproductive diseases caused by iron overload as well as lipid peroxidation, and provide a novel direction for the research and prevention of various male reproductive diseases.