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Due to global warming and the disturbance of the interannual variability of precipitation, the frequency of extreme drought events has increased. The impact of global climate change on water resources is becoming increasingly apparent, then it is particularly necessary to explore the carrying capacity of water ecological environment under extreme drought conditions, which can guarantee the ecological water security in river basins. This study takes the Guanzhong area of the Wei River Basin as an example, calculating the water environment carrying capacity of 40 areas in the Weihe Guanzhong area in different levels of years under extreme drought conditions by comprehensive evaluation model of carrying capacity and using geographic information system GIS to display the spatial distribution of water environment carrying capacity in 40 regions. According to the results of the spatial distribution of water environmental bearing capacity, four different schemes are designed to improve the bearing capacity. The first plan reduces the industrial water consumption and irrigation quota by 5%, the second plan increases the industrial water and sewage treatment rate on this basis. the third plan further improves the development and utilization rate of surface and groundwater, and the fourth plan, on the basis of the first three plans, supplies 600 million cubic meters of industrial and agricultural water to Guanzhong region. Through comparative analysis, without taking any measures, under the extreme drought conditions, the water environment carrying capacity of the 40 areas in Guanzhong is all in an unbearable state. Overall, plan 4 has the most significant improvement in the water environment-carrying capacity, especially the Dong zhuang Reservoir of the Jing River which has played a very important role in enhancing the water ecological environment carrying capacity of the downstream water of the Wei River. [ABSTRACT FROM AUTHOR]

The Jishishan Ms 6.2 earthquake occurred at 23:59 on December 18, 2023 in Gansu Province, China. We conducted a field survey to assess the hazards and damages caused by the earthquake and its associated geo-activities. Subsequently, we organized a seminar to discuss the possible causes of the destruction of a prehistoric site—Lajia Settlement—dated back to four thousand years B.P. and located only several kilometers away from the epicenter of the Jishishan earthquake. The Jishishan earthquake was unique for its hazard and disaster process, which featured ground shaking and a series of complex geological and geomorphological activities: sediment and soil spray piles, liquefaction, collapse, landslide, and mudflow along water channels. We define this phenomenon as the Jishishan earthquake ripple hazard (JERH). The most recent evidence from the JERH suggests that a prehistoric earthquake similar to the JERH, instead of riverine floods or earthquake-induced landslide dam outburst flood, as previously hypothesized, destroyed the Lajia Settlement. [ABSTRACT FROM AUTHOR]

Medullary Carcinoma of the Colon (MCC) is a rare histological subtype of colon cancer, and there is currently no recognized optimal treatment plan for it, with its prognosis remaining unclear. The aim of this study is to analyze the independent prognostic factors for MCC patients and develop and validate nomograms to predict overall survival (OS). A total of 760 patients newly diagnosed with MCC from 2004 to 2020 were selected from the Surveillance, Epidemiology, and End Results (SEER) database. All patients were randomly allocated to a training group and a validation group in a 7:3 ratio. Univariate and multivariable Cox regression analyses were conducted to identify prognostic factors and construct nomograms. The nomogram prediction model was evaluated and validated using receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA). The study found that elderly women are more susceptible to MCC, and the ascending colon and cecum are the most common sites of involvement. MCC is poorly differentiated, with stages II and III being the most common. Surgery is the primary treatment for MCC. The prognosis for patients with stage IV MCC is poor, with a median survival time of only 10 months. Independent prognostic factors for MCC include age, N stage, M stage, surgery, chemotherapy, and tumor size. Among them, age < 75 years and completion of chemotherapy were protective factors for colon medullary carcinoma, while N2 (HR = 2.18, 95%CI 1.40–3.38), M1 (HR = 3.31, 95%CI 2.01–5.46), no surgery (HR = 27.94, 95%CI 3.69–211.75), and tumor diameter > 7 cm (HR = 1.66, 95%CI 1.20–2.30) were risk factors for colon medullary carcinoma. The results of ROC, AUC, calibration curves, and DCA demonstrate that the nomogram prediction model exhibits good predictive performance. We have updated the demographic characteristics of colon medullary carcinoma and identified age, N staging, M staging, surgery, chemotherapy and tumor size as independent prognostic factors for colon medullary carcinoma. Additionally, we have established nomograms for prognostic prediction. These nomograms can provide personalized predictions and serve as valuable references for clinical decision-making. [ABSTRACT FROM AUTHOR]

The high-pressure behaviors of nitrogen-rich 1H-tetrazole (CH2N4) have been investigated by in situ synchrotron X-ray diffraction (XRD) and Raman scattering up to 75 GPa. A first crystalline-to-crystalline phase transition is observed and identified above ~3 GPa with a large volume collapse (∼18% at 4.4 GPa) from phase I to phase II. The new phase II forms a dimer-like structure, belonging to P1 space group. Then, a crystalline-to-amorphous phase transition takes place over a large pressure range of 13.8 to 50 GPa, which is accompanied by an interphase region approaching paracrystalline state. When decompression from 75 GPa to ambient conditions, the final product keeps an irreversible amorphous state. Our ultraviolet (UV) absorption spectrum suggests the final product exhibits an increase in molecular conjugation. [ABSTRACT FROM AUTHOR]

Premature senescence of nucleus pulposus (NP) cells and inflammation are two common features of degenerated discs. This study investigated the effects of the inflammatory cytokine TNF-α on the premature senescence of NP cells and the molecular mechanism behind this process. Rat NP cells were cultured with or without different concentrations of TNF-α for 1 and 3 days. The inhibitor LY294002 was used to determine the role of the PI3K/Akt pathway. NP cells that were incubated with TNF-α for 3 days followed by 3 days of recovery in the control medium were used to analyze cellular senescence. Results showed that TNF-α promoted premature senescence of NP cells, as indicated by decreased cell proliferation, decreased telomerase activity, increased SA-β-gal staining, the fraction of cells arrested in the G1 phase of the cell cycle, the attenuated ability to synthesize matrix proteins and the up-regulated expression of the senescence marker p16 and p53. Moreover, a high TNF-α concentration produced greater effects than a low TNF-α concentration on day 3 of the experiment. Further analysis indicated that the inhibition of the PI3K/Akt pathway attenuated the TNF-α-induced premature senescence of NP cells. Additionally, TNF-α-induced NP cell senescence did not recover after TNF-α was withdrawn. In conclusion, TNF-α promotes the premature senescence of NP cells, and activation of the PI3K/Akt pathway is involved in this process. [ABSTRACT FROM AUTHOR]