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The Southern Hunan area is located in the superposition of the Qin-Hang Cu-Pb-Zn polymetallic ore belt and the Nanling W-Sn-Mo polymetallic ore belt, which is an important window to study the mineralization of W-Sn-Mo and Cu-Pb-Zn polymetallic deposits. The Baoshan deposit is a large Cu-Pb-Zn polymetallic deposit in Southern Hunan Province with obvious zones of Cu mineralization and Pb-Zn mineralization: the central part of the Baoshan deposit demonstrates contact metasomatic (skarn) Cu mineralization, while the western, northern and eastern parts demonstrate hydrothermal vein Pb-Zn mineralization. However, the origin and evolution of the ore-forming fluid and mechanism of Cu and Pb-Zn mineral precipitation are still unclear. The metallogenic process of the Baoshan Cu-Pb-Zn deposit can be divided into four stages: (1) the early skarn stage (S1); (2) the late skarn stage (S2); (3) the Cu-Fe sulfide stage (S3); and (4) the Pb-Zn sulfide stage (S4). The results of microtemperature measurements and a Raman spectrometric analysis of fluid inclusions show that the ore-forming fluid was the H2O-NaCl (-CO2 ± N2 ± C2H6) system in the skarn stages (S1 + S2) and changed into the H2O-NaCl-CO2 (±N2 ± C2H6) system in the sulfide stages (S3 + S4). The temperature (S1: 436.6~548.2 °C; S2: 344.1~435.1 °C; S3: 134.1~413.1 °C; S4: 183.9~261.0 °C) and salinity (S1: 17.4~51.2 wt.%NaClequiv; S2: 13.6~41.7 wt.%NaClequiv; S3: 1.2~32.3 wt.%NaClequiv; S4: 1.8~9.6 wt.%NaClequiv) showed a downward trend from the early to late stages. From the skarn stages (S1 + S2) to the sulfide stages (S3 + S4), the ore-forming pressure results from the static rock pressure and the hydrostatic pressure, and the ore-forming depth is estimated to be about three to six km. The C-H-O isotopic compositions of hydrothermal minerals such as quartz and calcite indicate that the ore-forming fluid is predominately magmatic fluid, but a significant amount of meteoric water is added in the Pb-Zn sulfide stage (S4). The formation of the mineralization zonation of the Baoshan deposit is the result of many factors (e.g., stratigraphy, structure and metal precipitation mechanism): the Cu mineralization is controlled by the contact zone, and the Pb-Zn mineralization is controlled by the fault. In addition, the precipitation of Cu is mainly controlled by fluid boiling, while the precipitation of Pb and Zn is mainly controlled by the mixing of magmatic fluid and meteoric water. [ABSTRACT FROM AUTHOR]

The Baoshan Cu-Pb-Zn deposit is situated at the intersection of the Qin-Hang Cu polymetallic and Nanling W-Sn polymetallic metallogenic belts. The age, lithology, petrogenesis, and tectonic setting of granodiorite porphyry within the deposit remain subjects of debate. Additionally, there is a lack of comparative studies with the W-Sn-related granites in the region. This study conducted whole-rock major and trace element analysis, Sr-Nd isotope analysis, and zircon U-Pb dating on the Baoshan granodiorite porphyry. The zircon U-Pb age of the granodiorite porphyry is 162 ± 1 Ma. The whole-rock SiO2 and K2O contents range from 65.87 to 68.21 wt.% and 3.42 to 5.62 wt.%, respectively, indicating that the granodiorite porphyry belongs to high-potassium calc-alkaline I-type granite. The granodiorite porphyry is characterized by enrichment in LREE and depletion in HREE (LREE/HREE ratio = 6.2–21.2). The samples of granodiorite porphyry generally exhibit weak negative Eu anomalies or no Eu anomalies (δEu = 0.62–1.04, mean = 0.82). The (87Sr/86Sr)i and εNd(t) values are 0.707717–0.709506 and −7.54 to −4.87, respectively. The whole-rock geochemical composition and Sr-Nd isotopic values indicate that the magma originated from the partial melting of the Mesoproterozoic ancient crust and Neoproterozoic mafic juvenile lower crust, with the addition of high oxygen fugacity and water-rich lithospheric mantle melts. The source of the granodiorite porphyry in the Baoshan deposit is significantly different from the crust-derived metapelite source of the W-Sn-related granite in the area, indicating that different magma sources might be the main reason for the co-spatial and nearly contemporaneous development of Cu-Pb-Zn and W-Sn mineralization in the southern Hunan region. [ABSTRACT FROM AUTHOR]

The absorption, distribution, and transport trends of organic and inorganic arsenic (As) in honesuckle (Lonicera japonica) were studied using synchrotron X-ray fluorescence spectroscopy (μ-XRF). The root, stem, and leaf samples were analyzed by μ-XRF, proving that in the presence of dimethyl arsenate acid, a small amount of As accumulated in local areas of the epidermis and cortex of roots, while most of As migrated to the upper plant through the middle vascular column. After reaching the stem, As was mainly distributed in the outer skin, indicating that the root and stem of L. japonica blocked the transport of As in the plant. In the presence of As(iii), A large amount of As accumulated in the epidermis and cortex of the root, reducing its further transport from the plant roots. Once As entered the stem of L. japonica from the root, it achieved a strong transport capacity, thus causing severe harm to plants. The element correlation analysis revealed that As in L. japonica had the strongest correlation with Cu and Zn elements, for the future research on the influence of As pollution on plants, the interference based on the above two elements can be considered.

Background: The rationale for the pathogenesis of Alzheimer's disease (AD) is the production of amyloid-beta (Aβ) and its resultant toxic effects. Purpose: In this work, rats with AD were used as models to assess the modulatory effects of tanshinone IIA (tan IIA) in alleviating cognitive impairment, oxidative damage, inflammation and apoptosis. Materials and Methods: Aβ1–42 was injected bilaterally in the hippocampus to establish an AD rat model. The effects of tan II A on the learning and memory capacities of AD rats were detected by ethological experiments. Tan IIA's anti-inflammatory and antioxidant capacities were examined in this study using biochemical and immunohistochemical methods on rat hippocampus tissues. Results: The experimental data showed that the cognitive ability of rats could be significantly improved by tan IIA. Furthermore, fewer injured neuron apoptosis was demonstrated in the tan IIA rats than in the AD group. More importantly, on the one hand, we discovered that the tan IIA group had considerably lower levels of interleukin 1 beta, tumour necrosis factor-alpha and inducible nitric oxide synthase. On the other hand, tan IIA was discovered to prevent oxidative stress by raising glutathione and superoxide dismutase activity and lowering malondialdehyde, protein carbonyl and 8-hydroxy-2′-deoxyguanosine levels. Conclusion: Tan IIA can alleviate cognitive impairment and neuronal cell damage by inhibiting oxidative stress and inflammatory responses during AD. [ABSTRACT FROM AUTHOR]

Add SBS modified asphalt with 10% rock asphalt and 15% rubber powder as base material, and mix 0, 0.1%, 0.3%, 0.5% basalt fiber and appropriate basalt grade gravel to make asphalt flexible pavement mixture. The effect of basalt fiber content on road performance of pavement asphalt mixture was studied. The results show that with the increase of basalt fiber content by 0, 0.1%, 0.3%, 0.5%, the rutting test dynamic stability, low temperature bending failure strain and water immersion Marshall residual stability of pavement asphalt mixture increase first and then decrease, normal temperature bending failure strain is gradually increased. Adding appropriate amount of basalt fiber can effectively improve the road performance of the prefabricated curable asphalt mixture. [ABSTRACT FROM AUTHOR]

As a typical inland wetland, Yangguan nature reserve wetland in Dunhuang is one of the important stops of migratory route for birds, which is vulnerable and particular. Study on the community characteristics and species diversity of wetland has great significance for biodiversity protection. Based on the field investigation, the floristic composition, geographical elements and species diversity of wetland plants were studied in Yangguan reserve of Dunhuang. The results showed that 26 families, 56 genera and 74 species were recorded in the study area. The largest families were the Gramineae and Chenopodiaceae, accounting for 29.73% of the total. Herbs were the most abundant life-form, accounting for 77.03% of the total. The floral geographical elements of the plants were mainly composed of temperate zone distribution type. By using two way indicator species analysis (TWINSPAX), the vegetation in 36 sampling plots could be classified into 8 communities. The species diversity indexes of communities were relatively low, but had large differences among each other. According to the importance value, the Margalef richness index (Rm) ranged from 0 to 4.200. Simpson diversity index (D) was between 0 and 0.512; Shannon diversity index (H) ranged from 0 to 1.400, and Pielou evenness index (J) was within the range of 0.538 to 1.000. The results indicated that the plant species were relatively rare and simple in general, the species diversity of communities was low, and the ecological environment was fragile in Yangguan nature reserve of Dunhuang. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is a degenerative disease of the central nervous system characterized by the progressive impairment of neural activity. Studies have shown that 3,6′-disinapoyl sucrose (DISS) can alleviate the pathological symptoms of AD through the activation of the cAMP/CREB/BDNF signaling pathway. However, the exact biochemical mechanisms of action of DISS are not clear. This study explores metabolism of DISS in an AD mouse model, induced by the microinjection of a lentiviral expression plasmid of the APPswe695 gene into CA1 of the hippocampus. After gavage administration of DISS (200 mg/kg), the kidneys, livers, brains, plasma, urine, and feces were collected for UHPLC–Orbitrap mass spectrometry analysis. Twenty metabolites, including the prototype drug of DISS, were positively or tentatively identified based on accurate mass measurements, characteristic fragmentation behaviors, and retention times. Thus, the metabolic pathways of DISS in AD mice were preliminarily elucidated through the identification of metabolites, such as ester bond cleavage, demethoxylation, demethylation, and sinapic acid-related products. Furthermore, differences in the in vivo distribution of several metabolites were observed between the model and sham control groups. These findings can provide a valuable reference for the pharmacological mechanisms and biosafety of DISS. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is a neurodegenerative disorder with insidious onset and progressive development. There is an urgent need to find drugs that prevent and slow AD progression. We focus our attention on 3,6'-disinapoyl sucrose (DISS), an oligosaccharide with antidepressant and antioxidant activities. In this work, APP/PS1 transgenic mice were used to explore the neuroprotective impact of DISS to provide new applications for prevention and therapy of AD. This study aims to assess DISS's neuroprotective impact on learning and memory deficits in APP/PS1 transgenic mice using behavioral tests (Morris water maze, novel object recognition test, and passive avoidance test). Morphological alterations of hippocampus neurons were observed by Nissl staining and neuronal apoptosis was assessed by TUNEL assay. By using ELISA, the expressions of inflammatory factors were evaluated, and Western blotting was used to measure the protein expressions of neuron-related regulators in the hippocampus. DISS significantly ameliorated the cognitive disorder in APP/PS1 transgenic mice, reduced apoptosis by decreasing the ratio of Bax/B-cell lymphoma/leukemia-2 (Bcl-2) in hippocampal neurons, and restored the abnormal secretion of inflammatory factors (IL-2, TNF-α, IL-1β, and IL-6). Moreover, the gavage of high-dose DISS can boost the expressions of CREB/brain-derived neurotrophic factor (BDNF). Overall, our results indicate that DISS improves cognitive function in APP/PS1 transgenic mice by inhibiting neural apoptosis and activating the CREB/BDNF signal pathway. NEW & NOTEWORTHY In this study, for the first time, DISS was used in APP/PS1 transgenic mice to explore its neuroprotective effect. After gavage DISS for 1 mo, the impairment of learning and spatial memory ability and the loss of neurons in APP/PS1 mice were alleviated. DISS reduced a neuroprotective effect in AD mice via decreasing neuronal apoptosis, enhancing the expressions of CREB phosphorylation and BDNF, pointing to DISS as a new therapeutic target for AD.

Alzheimer's disease (AD) is a neurodegenerative disorder that damages health and welfare of the elderly, and there has been no effective therapy for AD until now. It has been proved that tanshinone IIA (tan IIA) could alleviate pathological symptoms of AD via improving non-amyloidogenic cleavage of amyloid precursor protein, decreasing the accumulations of p-tau and amyloid-β 1-42 (Aβ 1-42 ), and so forth. However, the further biochemical mechanisms of tan IIA are not clear. The experiment was undertaken to explore metabolites of tan IIA in AD rats induced by microinjecting Aβ 1-42 in the CA1 region of hippocampus. AD rats were orally administrated with tan IIA at 100 mg/kg weight, and plasma, urine, faeces, kidney, liver and brain were then collected for metabolites analysis by UHPLC-Q-Exactive Qrbitrap mass spectrometry. Consequently, a total of 37 metabolites were positively or putatively identified on the basis of mass fragmentation behavior, accurate mass measurements and retention times. As a result, methylation, hydroxylation, dehydration, decarbonylation, reduction reaction, glucuronidation, glycine linking and their composite reactions were characterized to illuminate metabolic pathways of tan IIA in vivo. Several metabolites presented differences in the distribution of tan IIA between the sham control and the AD model group. Overall, these results provided valuable references for research on metabolites of tan IIA in vivo and its probable active structure for exerting neuroprotection.

beta-amyloid peptide (Abeta) is considered to be responsible for the formation of senile plaques, which is the hallmark of Alzheimer's disease (AD). Oxidative stress, manifested by protein oxidation and lipid peroxidation, among other alterations, is a characteristic of AD brain. A growing body of evidence has been presented in support of Abeta(1-40) forming an oligomeric complex that binds copper at a CuZn superoxide dismutase-like binding site. Abeta(1-40)Cu(II) complexes generate neurotoxic hydrogen peroxide (H(2)O(2)) from O(2) via Cu(2+) reduction, though the precise reaction mechanism is unclear. The toxicity of Abeta(1-40) or the Abeta(1-40)Cu(II) complexes to cultured primary cortical neurons was partially attenuated when (+)-alpha-tocopherol (vitamin E) as free radical antioxidant was added at a concentration of 100 mM. The data derived from lactate dehydrogenase (LDH) release and the formation of H(2)O(2) confirmed the results from the MTT assay. These findings indicate that copper binding to Abeta(1-40) can give rise to greater production of H(2)O(2), which leads to a breakdown in the integrity of the plasma membrane and subsequent neuronal death. Groups treated with vitamin E exhibited much slighter damage, suggesting that vitamin E plays a key role in protecting neuronal cells from dysfunction or death.