Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2019-09-11 Cooperative journals: 《干旱区地理》
Abstract：利用2016年在克拉玛依酸雨观测站采集的降水样品，分析了降水中主要阴阳离子（F-、Cl-、NO3-、SO42-、Na+、NH4+、K+、Mg2+、Ca2+）、重金属元素（Al、Mn、Fe、Ni、Cu、Zn、Cd、Pb、Hg）、总碳总氮浓度特征及可能的来源。结果表明：该区降水pH值在5.1~6.88之间，雨量加权平均值为6.25，其中pH>5.6的样品占94%。降水中各离子雨量加权浓度的大小顺序为Ca2+> NH4+> SO42-> NO3-> Cl->Mg2+>Na+>K+>F-，表现出了内陆性大气降水的特征，其中Ca2+是最主要的阳离子，年均值为182.09 μeq·L-1，SO42-是最主要的阴离子，年均值为87.28 μeq·L-1，表明硫酸盐是该地区降水中的主要致酸物质。降水中总离子浓度秋季最高，春夏次之，冬季最低，其中SO42-、NO3-、NH4+、Ca2+、Na+浓度变化明显。相对酸度（FA）和中和因子（NF）计算结果表明99.5%的降水酸度被碱性成分中和，其中Ca2+的中和能力最强，其次是NH+4。降水中重金属元素Zn的均值最大，其次是Fe，最小的是Pb，与国内外城市比较，克拉玛依大气降水中大部分重金属含量都不高，其降水中有毒重金属污染较轻。可溶性总碳（DTC）、可溶性有机碳（DOC）和可溶性无机碳（DIC）浓度变化范围大，分别为1.62~9.97 mg·L-1、1.62~7.19 mg·L-1和0~3.75 mg·L-1，平均浓度分别为4.37 mg·L-1、3.60 mg·L-1和0.78 mg·L-1，可溶性总氮（DTN）的浓度变化范围为0.64~8.01 mg·L-1，年均含量为2.69 mg·L-1，都与降水量呈负相关关系，而DOC和DTN的湿沉降通量与降水量呈明显的正相关关系。基于相关性分析表明，SO42-和NO3-主要来自燃煤和化石燃料燃烧，Na+、Mg2+和Ca2+主要来自风沙、扬尘，大气中铵类化合物主要以铵的硝酸盐形式存在。各重金属元素之间相关性差异较大，重金属主要污染源为金属冶炼、燃煤及人为活动。克拉玛依大气降水的化学组成特征主要受人为活动、化工生产、燃煤以及沙尘活动等影响。
Subjects: Environmental Sciences, Resource Sciences >> Other Disciplines of Environmental Sciences, Resource Sciences submitted time 2021-03-02 Cooperative journals: 《干旱区研究》
Abstract：选取不同年限退/弃耕地（退耕1 a、2 a、4 a、8 a、13 a、20 a、30 a、40 a和CK）为研究对象，采用时空替代法，分析了不同年限退/弃耕地植被群落特征和土壤理化性质及其相关性。结果表明：（1）石羊河下游青土湖退/弃耕地40 a的植被恢复过程中，9个样方共出现15科29属43种植物，退/弃耕地物种构成表现为：多数种属于少数科、少数种属于多数科。植被演变分为：一年生草本和多年生植物快速生长期（1~2 a），一年生草本向多年生草本演变期（2~8 a），多年生草本向灌木演变期（8~20 a）和以灌木为主的稳定期（20~40 a）；（2）随退耕年限增加，土壤含水量呈先减小后增加最后波动式减小趋势，上层土壤含水量高于下层土壤含水量。各样方比例最大是细砂粒，粉粒次之，比例最小的是粗砂粒和黏粒，随退耕年限的变化，各粒径占比变化不大；（3）随退耕年限增加，土壤全氮和有机质均呈下降趋势，速效钾含量呈先增加后减小趋势，速效磷含量呈先减小后增加再减小趋势，表聚现象明显；（4）植被群落演替与土壤理化性质具有密切相关性。Margalef丰富度指数与土壤全氮和有机质呈极显著正相关关系，Shannon多样性指数与土壤容重和细砂粒呈显著的正相关关系，与土壤黏粒和粉粒呈显著负相关关系。退耕第4 a是青土湖退/弃耕地在恢复治理过程中关键时期。
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2019-09-09 Cooperative journals: 《干旱区研究》
Abstract： 通过测定石羊河下游民勤绿洲外围4个不同立地类型黑果枸杞群落植被特征和黑果枸杞株数、株高、冠幅等生物学特征，以及黑果枸杞分布格局的点坐标，采用空间点格局分析方法中的Ripley’s K函数，分析了民勤绿洲外围不同立地类型上黑果枸杞空间分布格局。结果表明：① 4个不同立地类型中植被物种数为：砾石地﹥盐碱地﹥固定或半固定沙丘地、覆沙地，植物群落结构比较简单，存在多个科单属单种现象。② 黑果枸杞株数在盐碱地中最多，覆沙地次之，固定或半固定沙丘地和砾石地中最少；而平均株高由高到低依次是固定或半固定沙丘地、盐碱地、覆沙地、砾石地；平均冠幅分布与平均株高类似。③ 在4个样地中，固定或半固定沙丘地和砾石地中的黑果枸杞呈现聚集分布；覆沙地中，黑果枸杞在较小尺度（0.2～0.5 m）呈现聚集分布，在较大尺度（1.5～2.5 m）呈现随机分布；盐碱地中，黑果枸杞种群表现为完全的随机分布。
Subjects: Medicine, Pharmacy >> Clinical Medicine submitted time 2022-10-28 Cooperative journals: 《中国全科医学》
Abstract： Background With the aging characteristics of dry, loose, inelastic and decreased tolerant skin, the elderly are more vulnerable to pressure injury by pressure. Appropriate decompression mattress is the key to prevent pressure injury. Objective The decompression effects of two types of mattresses were evaluated by analyzing the pressures and temperatures of sacrococcygeal skins in elderly bedridden patients in the supine position. Methods A total of 45 hospitalized elderly bedridden male patients who met the criteria from January 2021 to March 2022 were divided into two groups: Patients in group A used gel decompression mattresses (n=23); Patients in group B (n=22) used air decompression mattresses. The patients from both groups were repositioned every 2 hours for 7 days. Maximum sacrococcygeal pressure was measured using a continuous bedside pressure mapping system, and the skin temperature in the same location was measured using a hand-held thermometer. The linear mixed effect model was used to analyze and compare the skin pressure and temperature changes from two types of mattresses in the sacrococcygeal regions of the elderly bedridden patients to compare the decompression effect. Results The pressures and temperatures from these two group patients were comparable at baseline. The sacrococcygeal maximum pressure values increased by 1.29±1.25mmHg and 7.38±1.28mmHg respectively at 1h time points in spine position by two types of mattresses compared with baseline (P＜0.01); increased by 4.51±1.28mmHg and 14.96±1.31mmHg respectively in 2h time points (p<0.001). The pressures of the sacrococcygeal regions increased from both types of mattresses with the extension of time. However, the average increase ratio of pressure from the gel mattresses was less than that from the air mattresses (p<0.01). Sacrococcygeal skin temperatures increased by 0.07±0.04°C and 0.27±0.04°C from baseline at 1h time points in spine position from both group patients respectively (p<0.01). Also, temperatures increased by 0.18±0.06°C and 0.68±0.06°C at 2h time points, respectively (p<0.001). The skin temperature of the sacrococcygeal region increased with the extension of time. The average increase ratio of the temperature in the gel mattress group patients was less than that in the air mattress group (p<0.01). There was no resultant pressure injury in both group patients during the intervention. Conclusions The pressures and skin temperatures of sacrococcygeal regions of hospitalized elderly bedridden male patients increased in supine position in 1h and 2h time points using two kinds of decompression mattresses. However, the increased ratios of pressures and temperatures from gel decompression mattresses were less than that from air decompression mattresses. The results demonstrated that the gel decompression mattress is superior to the air decompression mattress in preventing the pressure injury.
Subjects: Medicine, Pharmacy >> Clinical Medicine submitted time 2022-07-26 Cooperative journals: 《中国全科医学》
Abstract： Background Although clinical and basic experiments have paid attention to the role and mechanism of calcium-sensing receptors in hypertensive diseases, there is still a lack of relevant research on its role and mechanism in hypertensive retinal diseases. Objective To investigate the expression levels of calcium-sensitive receptors (CaSR) in the hypertensive retina and the relationship with myocardial remodeling and retinal vascular changes in hypertension. Methods Fifteen 8-week-old homologous healthy normotensive rats (WKY) were selected as the normotensive (WKY) group, and 30 same-week-old spontaneously hypertensive rats (SHR) were randomly divided into the hypertensive (SHR) group and the inhibitor (SHR+NPS2143) group. the SHR+NPS2143 group was injected intraperitoneally with the CaSR inhibitor NPS2143. Blood pressure were monitored by non-invasive blood pressure monitor. Retinal pathological changes were detected by hematoxylin and eosin staining (HE). Myocardial collagen deposition was observed by Masson staining. The distribution and expression of CaSR and vascular endothelial growth factor A (VEGFA) in the retina were observed by immunohistochemical staining and quantitative real-time fluorescence PCR (qRT-PCR). Results Compared with 8W and 24W WKY, the SHR group at the same week of age had increased blood pressure (P < 0.05), retinal structural disorder, increased thickness (P < 0.01), and reduced levels of CaSR expression and increased levels of VEGFA expression in the retina (P < 0.01), NPS2143 intervention up to 24W significantly increased SHR blood pressure (P < 0.05), retinal structural disorder aggravated with a significant increase in thickness (P < 0.01), and a further decrease in CaSR expression and a further increase in VEGFA expression in the retina (P < 0.01). Compared with the same week-old WKY, there was no statistical difference in HW/BW% and LVW/BW% in the 8W SHR group, and no significant increase in myocardial collagen accumulation was seen (P > 0.05), while HW/BW% and LVW/BW% were elevated and myocardial collagen accumulation was increased in the 24W SHR group, and NPS2143 intervention up to 24W significantly elevated HW/BW% and LVW/BW% in SHR. significantly increased the area of myocardial collagen accumulation in SHR (P < 0.05). Conclusion CaSR lowers blood pressure, improves myocardial remodeling, and delays the development of hypertension-induced retinal vasculopathy by inhibiting VEGFA expression.
Subjects: Biology >> Botany submitted time 2018-12-19 Cooperative journals: 《广西植物》
Abstract： 樟叶越桔(Vaccinium dunalianum Wight)是广泛应用于化妆品行业皮肤美白的天然美白活性剂原料熊果普的主要植物来源之一，采用植物组织培养技术进行种苗繁殖时，现有的配方获得的生根苗基部会形成愈伤组织，影响移栽。为解决樟叶越桔组培苗生根质量不佳、移栽成活率低的问题，本研究以樟叶越桔继代苗为试验材料，采用单因子实验从激素类型及浓度、培养基类型和蔗糖质量浓度对其生根的适宜条件进行了筛选，并进一步研究了不同基质配比对樟叶越桔移栽苗存活率的影响。结果表明:激素种类和浓度、培养基类型对樟叶越桔生根率影响最大，其次为蔗糖质量浓度;最适合樟叶越桔生根的激素及浓度为IBA 2.0mg.L_1、基本培养基类型为1/4MS、蔗糖质量浓度为15 g}L-'，樟叶越桔组培苗最佳生根培养基为1/4MS + IBA 2.0 mg}L-1+活性炭0.1 g}L-'+蔗糖15 g}L-'，生根率达100%，平均生根数为7.67条/株;根系呈辐射状、基部无愈伤组织，组培苗生长健壮、叶色浓绿;樟叶越桔组培苗移栽时以全腐殖土基质为佳，成活率达83.7%，植株叶片舒展，生长状况良好。本研究建立的优化体系有效地提高了樟叶越桔组培生根苗的生根率和生根质量，解决了后期移栽成活困难的问题，为优良的樟叶越桔植株规模化生产提供了科学依据和技术支持。
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