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The construction of diabatic potential energy surfaces (PESs) for the SiH2+ system, related to the ground (12A′) and excited states (22A′), has been successfully achieved. This was accomplished by utilizing high-level ab initio energy points, employing a neural network fitting method in conjunction with a specifically designed function. The newly constructed diabatic PESs are carefully examined for dynamics calculations of the Si+(2P1/2, 3/2) + H2 reaction. Through time-dependent quantum wave packet calculations, the reaction probabilities, integral cross sections (ICSs), and differential cross sections (DCSs) of the Si+(2P1/2, 3/2) + H2 reaction were reported. The dynamics results indicate that the total ICS is in excellent agreement with experimental data within the collision energy range studied. The results also indicate that the SiH+ ion is hardly formed via the Si+(2P3/2) + H2 reaction. The results from the DCSs suggest that the "complex-forming" reaction mechanism predominates in the low collision energy region. Conversely, the forward abstraction reaction mechanism is dominant in the high collision energy region. [ABSTRACT FROM AUTHOR]

Prostate cancer has the second highest incidence among male malignancies. Only a few studies exist on the inhibitory effects of maslinic acid (MA) on prostate cancer. Herein we found that MA inhibits prostate cancer cell proliferation by decreasing CDK2, CDK4, and CDK6 expression and concurrently increasing p27, Rb, p-Rb expression. Further, MA was observed to induce prostate cancer cell autophagy by increasing the expression of p53, p-p53, ULK1, Beclin1, Atg7, and Atg5 and the ratio of LC3-II/I and concurrently decreasing the expression of ERK1/2 and mTOR. In addition, MA induced RM-1 cell ferroptosis by regulating glutathione, glutamate, and oxidized glutathione concentrations, inhibiting SLC7A11 activity, and downregulating GPX4 expression. Integrated metabolome and transcriptome analysis led to the identification of key pathways (e.g., pathways in cancer and glutathione metabolism). Real-time quantitative PCR confirmed that MA regulates the expression of ABCA1 , JUN , and NFKBIA. In vivo , we demonstrated that 50 mg/kg MA significantly inhibited the growth of tumors established using RM-1 cells. To summarize, we report that MA inhibits prostate cancer cell growth both in vitro and in vivo by inducing autophagy and ferroptosis via transcriptomic and metabolomic reprogramming. [ABSTRACT FROM AUTHOR]

Jinci spring is a famous karst spring in Shanxi Province, and its backflow is an ecological restoration goal of the Shanxi Provincial government. Composed of Nanlao spring, Shengmu spring, and Shanli spring, Jinci spring is exposed at the foot of Xuanweng mountain in the western mountains of Taiyuan, twenty-five kilometers away from the city center, and it is a concentrated discharge point for karst water in the Jinci spring area. Karst water in the spring area is mainly supplied by atmospheric precipitation infiltration and leakage from rivers and reservoirs. Karst water in the Jinci spring area is an important water source for people's life and industrial and agricultural production in Taiyuan City. In recent years, with the intensification of climate change, large-scale development of karst water, coal mining and other human activities, especially after the construction of the second reservoir of the Fenhe river, the karst hydrogeological conditions in the spring area have undergone fundamental changes, with the spring area expanding from 2,030 km2 to 2,713 km2, which has affected the evaluation, management and protection of karst water resources in the spring area. The original zoning of protected areas can no longer meet the needs of water resource management and protection. Therefore, it is urgent to re-zone the protected areas and formulate corresponding protection measures. In terms of the problems on water quality and quantity, there exist differences in the causes, regions, and protective measures, and thus LIANG Yongping et al. proposed the concepts of "water quantity vulnerability" and "water quality vulnerability", as well as a method of "first classifying, and then grading" for the zoning of karst aquifer protected areas.This study focuses on the hydrogeological conditions of special recharge, runoff, and discharge in the karst water system of North China, as well as the main influencing factors of the antifouling performance of karst aquifer systems. It combines European methods and "water vulnerability assessment" to evaluate the antifouling performance. Based on infiltration duration of karst water in the unsaturated zone, leakage of rivers and reservoirs, precipitation infiltration in different regions, and replacement of karst aquifer media structure with water abundance, this study selects four factors to evaluate the antifouling performance of karst aquifers in North China, including the thickness of unsaturated zone, the amount of infiltration recharge, the lithology of overlying strata, and the water abundance of karst aquifers. Taking the newly divided karst water system in the Jinci spring area as the evaluation object, this study aims to evaluate the vulnerability of karst water system in the spring area and to zone the protected areas.The results show as follows, (1) The protected areas are mainly distributed in Jinci park and its surrounding areas. (2) The first-class protected areas are mainly distributed in the main stream of the Fenhe river, the exposed areas of carbonate rocks in the front of western mountains of Taiyuan, and the leakage sections of carbonate rocks in Tunlanchuan, the Tianchi river and the Liulin river. (3) The second-class protected areas are mainly distributed in the north of the spring area and the north bank of the Fenhe river. (4) The quasi-protected areas are mainly distributed in the south bank of the Fenhe river and the Taiyuan basin in the southeast. The newly zoned protected areas for spring water quality can provide a basis for the rational protection and scientific utilization of karst water resources in the Jinci spring area [ABSTRACT FROM AUTHOR]

For the treatment of MRSA-infected wounds, the spatiotemporally sequential delivery of antibacterial and anti-inflammatory drugs is a promising strategy. In this study, ROS-responsive HA-PBA/PVA (HPA) hydrogel was prepared by phenylborate ester bond cross-linking between hyaluronic acid-grafted 3-amino phenylboronic acid (HA-PBA) and polyvinyl alcohol (PVA) to achieve spatiotemporally controlled release of two kinds of drug to treat MRSA-infected wound. The hydrophilic antibiotic moxifloxacin (M) was directly loaded in the hydrogel. And hydrophobic curcumin (Cur) with anti-inflammatory function was first mixed with Pluronic F127 (PF) to form Cur-encapsulated PF micelles (Cur-PF), and then loaded into the HPA hydrogel. Due to the different hydrophilic and hydrophobic nature of moxifloxacin and Cur and their different existing forms in the HPA hydrogel, the final HPA/M&Cur-PF hydrogel can achieve different spatiotemporally sequential delivery of the two drugs. In addition, the swelling, degradation, self-healing, antibacterial, anti-inflammatory, antioxidant property, and biocompatibility of hydrogels were tested. Finally, in the MRSA-infected mouse skin wound, the hydrogel-treated group showed faster wound closure, less inflammation and more collagen deposition. Immunofluorescence experiments further confirmed that the hydrogel promoted better repair by reducing inflammation (TNF-α) and promoting vascular (VEGF) regeneration. In conclusion, this HPA/M&Cur-PF hydrogel that can spatiotemporally sequential deliver antibacterial and anti-inflammatory drugs showed great potential for the repair of MRSA-infected skin wounds. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study is to evaluate the long-term efficacy and safety of ultrasound-guided percutaneous laser ablation (PLA) for the treatment of elderly patients with papillary thyroid microcarcinoma (PTMC). Methods: From September 2015 to April 2017, 38 elderly patients with PTMC confirmed through fine-needle aspiration biopsy (FNAB) were treated with PLA. Before the treatment, the location and volume of the nodule together with the patients’ symptoms were evaluated. Twenty-four hours after the treatment, contrast-enhanced ultrasound (CEUS) was performed to evaluate the completeness of the ablation. To evaluate the volume of the ablation area and recurrence or metastasis, ultrasound examination was performed at 1, 3, 6, and 12 months after the treatment and every 6 months thereafter. FNAB was performed for any suspicious recurrence or metastasis lesions. Result: The ablation of all the 38 patients was all achieved completely as confirmed by CEUS. No obvious complications were found. The success rate of single ablation was 100%. The average follow-up time was 64.58 ± 5.29 months (60–78 months). By the time of the last follow-up, 31 (81.58%) ablation lesions disappeared completely and seven (18.42%) ablation lesions showed scar-like changes. The volume of nodules was 40.69 ± 16.45 mm3 before operation, which decreased to 0.22 ± 0.76 mm3 by the end of 42 months, and all nodules disappeared 4 years after ablation (P < 0.01). At 6, 12, 18, 24, 30, 36, and 42 months after ablation, the average volume reduction rates (VRRs) were 12.09%, 31.21%, 50.9%, 72.06%, 84.79%, 95.65%, and 100%, respectively. Of all the patients enrolled, one patient (2.6%) had local recurrence and was treated with PLA again. No regrowth of treated nodule or lymph node metastasis and distant metastases was detected. Conclusion: Ultrasound-guided PLA is effective and safe for the treatment of elderly patients with PTMC who are ineligible for surgery. [ABSTRACT FROM AUTHOR]

To investigate the effects and mechanisms of resveratrol on glucolipid metabolism in diabetic humans. In this paper, we introduced the knowledge discovery theory into the data processing of the factors related to the pathogenesis of type 2 diabetes for the first time, and identified valid, potentially useful, and understandable pathogenesis patterns from a large amount of measured data. A data mining C4.5 algorithm was used to classify 17072 validated cross-sectional health survey data from the whole population according to the characteristics of type ρ diabetes data. A human model of diabetes mellitus was prepared by high sugar and high fat diet plus low dose streptozotocin (STZ, 35 mg/kg) and randomly grouped into four groups: the normal control group, the model group, the resveratrol group, and the pioglitazone group. 8 animals in each group were treated with the corresponding drugs for 8 weeks. Hepatic steatosis and damage were significantly reduced compared with the model group as observed by HE staining. Resveratrol has obvious effects on regulating glucolipid metabolism, and its mechanism of action is associated with its ability to increase the antioxidant activity of the body, activate the Akt signaling pathway, and improve liver pathological damage. [ABSTRACT FROM AUTHOR]

Karst groundwater in the Niangziguan spring fields is the main source to supply domestic and industrial water demands in Yangquan City, China. However, the safety of water supply in this region has recently suffered from deteriorating quality levels. Therefore, identifying pollution sources and causes is crucial for maintaining a reliable water supply. In this study, a systematic sample collection for the karst groundwater in the Niangziguan spring fields was implemented to identify hydrochemical characteristics of the karst groundwater through comprehensive analyses of hydrochemistry (piper diagram, and ion ratios,) and stable isotopes (S and H-O). The results show that the karst groundwater in the Niangziguan spring fields was categorized as SO4·HCO3-Ca·Mg, HCO3·SO4-Ca·Mg, and SO4-Ca types. K+, Cl-, and Na+ are mainly sourced from urban sewage and coal mine drainage. In addition, SO42− was mainly supplied by the dissolution of gypsum and the oxidation of FeS2 in coal-bearing strata. It is noteworthy that, based on H-O and S isotopes, 75% of the karst groundwater was contaminated by acidic water in coal mines at different degrees. In the groundwater of the Niangziguan spring field, the proportions of SO42− derived from FeS2 oxidation were 60.6% (N50, Chengxi spring), 30.3% (N51, Wulong spring), and 26.0% (N52, Four springs mixed with water). Acid mine drainage directly recharges and pollutes karst groundwater through faults or abandoned boreholes, or discharges to rivers, and indirectly pollutes karst groundwater through river infiltration in carbonate exposed areas. The main source of rapid increase of sulfate in karst groundwater is acid water from abandoned coal mines. [ABSTRACT FROM AUTHOR]

Integration of the information from hydrochemical data, statistical analysis and modeling technique is crucial for extending our knowledge of hydrochemistry of karst aquifers. In this paper, conventional graphical methods, statistical analysis and PHREEQC inverse modeling were used to investigate the hydrogeochemical characteristics and evolution processes of karst groundwater in Jinci spring area. The results showed that the dominant hydrochemical types of karst groundwater determined by Piper diagram were Ca·Mg–SO4·HCO3, Ca·Mg–SO4, Ca–SO4, Ca–SO4·HCO3 and Ca–HCO3, and the main components of karst groundwater were dominated by rock–water interactions based on statistical analysis. Ca2+, Mg2+ and HCO3− originated mainly from the dissolution of calcite and dolomite; SO42− came mostly from gypsum dissolution and pyrite oxidation; and the source of Na+ and Cl− could either be major from halite dissolution or cation exchange. Moreover, PHREEQC inverse modeling indicated that calcite, gypsum and CO2 (g) were dissolved, and Ca–Mg exchange prevailed along the flow path (from recharge area to runoff area); the dissolution of gypsum, dolomite and CO2 (g), and halite precipitation, and Na–Mg and Ca–Mg exchange occurred along runoff area to discharge area; and there were the dissolution of carbonate, gypsum, halite and CO2 (g), Na–Mg and Ca–Mg exchange from deep buried area to discharge area. [ABSTRACT FROM AUTHOR]

The chemical structures and topologies of the crosslinks in supramolecular networks play a crucial role in their properties and functions. Herein, the preparation of a type of poly(N‐isopropylacrylamide) (PNIPAAM)‐based supramolecular networks crosslinked by emissive hexagonal metallacycles is presented. The topological connections in these networks greatly affect their properties, as evidenced by their differences in absorption, emission, lower critical solution temperature, and modulus along with the variation of crosslinking densities. The integration of PNIPAAM and metallacycles in the networks benefits them improved bioavailability, making them serve as reagents for bacterial imaging and killing. This study provides a strategy to prepare cavity‐crosslinked polymer networks for antibacterial applications. [ABSTRACT FROM AUTHOR]

The chemical structures and topologies of the crosslinks in supramolecular networks play a crucial role in their properties and functions. Herein, the preparation of a type of poly(N‐isopropylacrylamide) (PNIPAAM)‐based supramolecular networks crosslinked by emissive hexagonal metallacycles is presented. The topological connections in these networks greatly affect their properties, as evidenced by their differences in absorption, emission, lower critical solution temperature, and modulus along with the variation of crosslinking densities. The integration of PNIPAAM and metallacycles in the networks benefits them improved bioavailability, making them serve as reagents for bacterial imaging and killing. This study provides a strategy to prepare cavity‐crosslinked polymer networks for antibacterial applications. [ABSTRACT FROM AUTHOR]

Developing physical double‐network (DN) removable hydrogel adhesives with both high healing efficiency and photothermal antibacterial activities to cope with multidrug‐resistant bacterial infection, wound closure, and wound healing remains an ongoing challenge. An injectable physical DN self‐healing hydrogel adhesive under physiological conditions is designed to treat multidrug‐resistant bacteria infection and full‐thickness skin incision/defect repair. The hydrogel adhesive consists of catechol–Fe3+ coordination cross‐linked poly(glycerol sebacate)‐co‐poly(ethylene glycol)‐g‐catechol and quadruple hydrogen bonding cross‐linked ureido‐pyrimidinone modified gelatin. It possesses excellent anti‐oxidation, NIR/pH responsiveness, and shape adaptation. Additionally, the hydrogel presents rapid self‐healing, good tissue adhesion, degradability, photothermal antibacterial activity, and NIR irradiation and/or acidic solution washing‐assisted removability. In vivo experiments prove that the hydrogels have good hemostasis of skin trauma and high killing ratio for methicillin‐resistant staphylococcus aureus (MRSA) and achieve better wound closure and healing of skin incision than medical glue and surgical suture. In particular, they can significantly promote full‐thickness skin defect wound healing by regulating inflammation, accelerating collagen deposition, promoting granulation tissue formation, and vascularization. These on‐demand dissolvable and antioxidant physical double‐network hydrogel adhesives are excellent multifunctional dressings for treating in vivo MRSA infection, wound closure, and wound healing. [ABSTRACT FROM AUTHOR]

In Northern China, karst systems in widely distributed carbonate rocks are one of the most important water supplies for local inhabitants. Constrained by the specific geological and geomorphological conditions, most karst water in this region is discharged as individual or groups of springs. This paper summarizes the characteristics, chemistry, and environmental quality of these karst systems in Northern China. Five structural models of karst water systems were identified based on the relationships between the karst geological strata and karst groundwater flow fields. These specific structural models may closely relate to the attendant environmental geological issues and consistent risks from pollution. Over the past 40 years, the karst water systems in Northern China have suffered from various environmental problems, including deteriorating water quality, the drying up of springs, a continuous decline in the level of karst water, and so on. Based on the field investigation and previous data, a preliminary summary is provided of the environmental problems related to the development and evolutionary trends of karst water in this region. The results highlight the significant challenges associated with karst water, and it is essential that all segments of society be made aware of the situation in order to demand change. In addition, the study provides a scientific basis for the management, protection, and sustainable utilization of karst water resources. [ABSTRACT FROM AUTHOR]

Atom transfer radical addition (ATRA) of 2-chlorodithiane onto aryl alkynes through the use of di- tert-butyl peroxide as an oxidant at room temperature directly affords a variety of synthetically valuable β-chloro-( Z)-vinyl dithianes in good yields with high regioselectivities and without the assistance of any transition metals. It provides an operationally simple pathway to access vinyl dithianes with controlled formation of a new C(sp2)C bond and a C(sp2)Cl bond. [ABSTRACT FROM AUTHOR]

Background: To investigate the renal microvascular injury in chronic aristolochic acid nephropathy (AAN) and the protective effects of Cozaar. Methods: Male Sprague-Dawley rats were randomized into three groups. Rats in the model group received Caulis Aristolochiae manshuriensis (CAM) decoction by gavage (10 mL/kg/day); those in the Cozaar group were gavaged with CAM and Cozaar (33.3 mg/kg/day); and those in the control group only received an equal daily volume of saline solution by gavage. Kidney tissues were observed under a light and electron microscope. CD34, caspase-3, and bone morphogenetic protein-7 (BMP-7) were determined by immunohistochemistry, and expressions of angiopoietin (Ang) 1 and 2, Tie-2, BMP-7, and vascular endothelial growth factor (VEGF) mRNA were monitored via real-time polymerase chain reaction (PCR). Results: (1) The kidney tissue injury in the chronic AAN model group was apparent, compared to the normal structure in the normal control group, and the Cozaar group showed relieved injury. (2) The expression of caspase-3 in the model group was elevated, while expressions of BMP-7 and CD34 were decreased ( p < 0.05). Cozaar lessened caspase-3 expression ( p < 0.05) and promoted BMP-7 and CD34 expressions ( p < 0.05). (3) Real-time PCR demonstrated a downregulation of Ang-1, Tie-2, BMP-7, and VEGF mRNA ( p < 0.05) and an upregulation of Ang-2 mRNA ( p < 0.01) in the renocortex, while Cozaar upregulated the expression of Ang-1, Tie-2, BMP-7, and VEGF mRNA ( p < 0.05). Conclusion: Renal microvascular injury was observed in chronic AAN, which was hypothetically correlated with a lack in the expressions of Ang-1, BMP-7, Tie-2, and VEGF and an excess in caspase-3 and Ang-2. Cozaar can significantly ameliorate the renal microvascular injury and protect renal function. [ABSTRACT FROM AUTHOR]

A novel molecular imprinted solid-phase extraction technique was developed by using microspheres prepared by modifying the silica through a sol-gel process with a layer of homogeneous and compact molecularly imprinted polymer (MIP), which was synthesized with 3-aminopropyltriethoxysilane and phenyltrimethoxysilane as functional monomers, diethylstilbestrol (DES) as the template, and tetraethoxysilane as the cross-linker. The saturated adsorption capacity of the MIP under the condition of continuous loading of target solution was 0.213 mg g−1, and the imprinting factor reached 6.0. The selectivity factor of the MIPs for bisphenol A and 4-tert-butylphenol were 3.5 and 9.6, respectively. The molecular imprinted solid-phase extraction (MISPE) is a viable and efficient technique for extraction of DES from chicken samples with a recovery ofmore than 85%. The limit of detection (LOD) was determined to be 8 ng g−1. [ABSTRACT FROM AUTHOR]

Background Studies have hypothesized that alterations in haemodynamics and rheological properties in the main vessels like the main stem of the carotid artery or the internal carotid arteries are responsible for the formation of cerebral aneurysms. Aims The objectives of the current analyses were to collate data that have examined the occurrence of cerebral aneurysm with coexisting internal carotid artery stenosis. Methods Data sources were collated from detailed Pub Med search obtained from 1990 till current. Published literature that deals with the epidemiologic properties as well as prevalence was scanned for data extraction. Publications that reported coexistence of internal carotid artery stenosis with intracranial aneurysm, detected by any modality of imaging, was included in the current study. Spearman's correlation analyses were used to obtain significant information of coexistence of an intracranial aneurysm with an extracranial internal carotid artery stenosis. Results The frequency of concurrent extracranial internal carotid artery stenosis and an unruptured cerebral artery aneurysm is not known exactly, but has been estimated to be approximately 4%. The major limitations of the current analyses actually can be retrospectively traced to the lack of detailed analyses in this important area of investigation. Conclusions Although low in absolute occurrence, there is a significant correlation of the existence of an intracranial aneurysm with carotid artery stenosis. Thus, if peripheral stenosis is detected by any imaging modality including carotid Ultrasonography scan, we recommend digital subtraction intracranial angiography to detect any potential aneurysm and define its radiologic morphology. [ABSTRACT FROM AUTHOR]