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1.
An experiment was designed using human ribs placed in different environments to document how moisture and temperature affect the bone mass according to the postmortem interval. The bones were defleshed, weighed and partially buried, with some ribs being left unburied as controls. The ribs were weighed daily, and the mass loss was monitored over a period of 90 days. The results showed that significant differences in bone mass loss exist between environments, where the bone mass loss was significantly faster in an environment with low moisture content. This mass loss is thought to be primarily associated with the desiccation of the body and then for a greater part, with the atmospheric moisture content. However, the loss of bone mass can also be explained by early alterations in the organo-mineral matrix which were highlighted by Raman spectroscopy method.  相似文献   
2.
The condition of heritage and historic timber constructions depends on how they are exploited. Numerous environmental factors degrade the physical and mechanical properties of timber and hence, affect the load-bearing capacity of constructions. As a result, frequent evaluations of their technical condition become necessary. Currently, modern technologies allow for extensive diagnostics of timber constructions using non-destructive and semi-destructive methods; yet, in contrast to classical laboratory tests, there is insufficient knowledge of the impact of individual factors on the results of such studies. This article presents an assessment of the influence of the moisture content of timber elements on the results of ultrasonic stress wave, sclerometric, and resistance drilling tests. Additionally, computed tomography scans were performed on selected samples to demonstrate the destruction mechanism occurring during the semi-destructive tests. The research involved three types of wood: pine, spruce, and fir of different moisture contents. The results reveal a strong relation between the moisture of timber and all the tests conducted in terms of both hygroscopic and capillary moisture.  相似文献   
3.
Soil Microbial Fuel Cells (MFCs) are devices that can generate electricity by using the flooded soil's anode respiring microbial consortium. When the MFC starts to work, the microbial community in the anode vicinity rapidly changes. This shift in the microbial community results in many dead cells that may release their DNA (relic DNA) and obscure culture independent estimates of microbial community composition. Although relic DNA is expected to increase in MFCs, the effect of relic DNA has not been investigated in the soil MFCs system. In this study the effect of the MFCs on the soil microbial community composition within the soil profile and the influence of relic DNA were investigated. Microbial community analysis revealed that the MFCs deployment significantly influenced the community composition within the soil profile. The phylum Proteobacteria (34.4% vs 23.6%) and the class Deltaproteobacteria (16.8% vs 5.9%) significantly increased in the MFCs compared to the control, while the phylum Firmicutes (24.0% vs 28.7%) and the class Sphingobacteria (5.3% vs 7.0%) were more abundant in the control. Furthermore, the archaeal phyla Euryarchaeota (40.7% vs 52.3%) and Bathyarchaeota (10.1% vs 17.3%) were significantly lower in the MFCs, whereas the phylum Woesearchaeota (DHVEG6) (24.4% vs 19.4%) was slightly enhanced. Moreover, the results showed that relic DNA can affect the relative abundance of Geobacter and Candidatus Methanoperedens, however, it has no significant effects on the microbial community structure. These results indicate that MFCs can influence the soil microbial community profile, nevertheless the relic DNA generated has minimum effect on the culture independent estimates of microbial community composition.  相似文献   
4.
Herein, we report the case of a 74-year-old man diagnosed with Legionella pneumonia detected by Loop-Mediated Isothermal Amplification (LAMP) method, which was suspected to have been transmitted from the potting soil. Legionella longbeachae was identified in the sputum culture. The patient was intubated and maintained on mechanical ventilation. Antimicrobial therapy with azithromycin was also administered. His symptoms were resolved and he was discharged after 26 days of hospitalization. Legionella longbeachae pneumonia rarely occurs in Japan, and published literature of Legionella longbeachae pneumonia cases in Japan was reviewed. Patients with severe pneumonia exposed to potting soils, but with negative urinary antigen test results, should be examined by LAMP method.  相似文献   
5.
Controlling residual solvent levels is a major concern in pharmaceutical freeze-drying from co-solvent systems. This review provides an overview of the factors influencing this process and estimates their potential to reduce residual solvents in freeze-dried products. Decreased solvent contents are potentially correlated with the lower solid content, complete excipient crystallization, higher water solubility, and smaller molecular sizes of the solvent. Although no general rule can be derived for the selection of appropriate freezing conditions, the freezing stage appears to play a major role in subsequent volatile retention. In contrast, diverse secondary drying conditions do not appear to impact the amount of solvent retained in lyophilisates, and modification of this stage is thus not assumed to be expedient. Co-solvents are strongly entrapped in an amorphous product matrix as soon as the local moisture content decreases below a certain level. Thus, the moisture content in the dried product layer adjacent to the sublimation interface might be a key factor. Therefore, extension of the high moisture content period during the primary drying phase as well as a postlyophilization humidification of the dried products are presumably promising approaches to promote solvent release.  相似文献   
6.
Gas-to-liquid (GTL) products are synthetic hydrocarbons produced from natural gas using a catalytic process known as the Fischer–Tropsch process. This process yields a synthetic crude oil that consists of saturated hydrocarbons which can subsequently be refined to a range of products analogous to those obtained from petroleum refining. However, in contrast to their petroleum-derived analogs, GTL products are essentially free of unsaturated or aromatic compounds and do not contain any sulfur-, oxygen-, or nitrogen-containing compounds. Under new chemical substance notification requirements, an extensive testing program covering the entire portfolio of GTL products has been undertaken to assess their hazardous properties to human health and environment. The results of these studies have been summarized in a two-part review. Part 1 provides an overview of the mammalian toxicity hazardous properties of the various GTL products. This second part of the review focuses on the aquatic, sediment, terrestrial, and avian toxicity studies which assess the ecotoxicological hazard profile of the GTL products. Many challenges were encountered during these tests relating to dosing, analysis and interpretation of results. These are discussed with the intent to share experiences to help inform and shape future regulatory mandates for testing of poorly soluble complex substances. As was the case with the mammalian toxicology review, there were a few cases where adverse effects were found, but overall the GTL products were found to exert minimal adverse ecotoxicological effects and these were less severe than effects observed with their conventional, petroleum-derived analogs.  相似文献   
7.
目的:本文研究了表面水分和不同种类的手套对于硅橡胶印膜材料聚合时间的影响.方法:使用3种手套:一次性聚乙烯塑料薄膜手套,灭菌橡胶医用手套(无粉),以及橡胶检查手套(预撒粉),分别在潮湿和干燥环境下手动混合DENT SILICONE-PLUS重体型硅橡咬印模材,并记录其硬化时间.结果:干燥情况下使用塑料薄膜手套时,橡胶印模材聚合时间最短,平均2分10秒;乳胶材料和表面水分均可延长聚合时间,达到3~分钟时间;而预撒粉则可显著延长聚合时间,超过1小时.结论:临床运用硅橡胶制取印模时,建议使用一次性聚乙烯塑料薄膜手套在干燥环境下进行操作,预撒粉的橡胶检查手套必须更换,以避免操作失败.  相似文献   
8.
目的 了解韶关市不同地域土壤中土源性寄生虫的污染状况,为开展寄生虫防治提供科学依据。方法 2019年5—10月于韶关市东(武江区)、北(浈江区)、中(曲江区)不同地区的采集土壤标本共900份,采用水洗沉淀法、氯化钠饱和溶液漂浮法和试管滤纸培养法检测土壤标本土源性寄生虫的污染情况,采用镜检法分辨检出土源性寄生虫种类,应用SPSS 21.0 统计学软件处理和分析数据。结果 900份土壤标本中,蠕虫总检出率为18.78%(169/900),其中武江区为23.30%(48/206)、曲江区为8.85%(23/260)、浈江区为22.58%(98/434),差异有统计学意义(P<0.05);将采样土分为种植耕地、公厕周边、公园周边、马路边绿化带、居民住宅区周边等不同土地类型,蠕虫检出率最高的土地类型为种植耕地,检出率为21.37%(140/655),其次是居民住宅区周边的土壤,为15.66%(13/83);检出蠕虫种类分别为钩虫、蛔虫、东方毛圆线虫、鞭虫、肺吸虫、姜片虫、粪类圆线虫,其中检出钩虫最多,检出率为14.11%(127/900),其次为蛔虫,检出率为2.11%(19/900)。三个地区蠕虫总检出率、各地区种植耕地蠕虫检出率、各区公共厕所周边蠕虫检出率、各区钩虫检出率及各区蛔虫检出率差异有统计学意义。结论 韶关市各地区的土壤中仍存在多种寄生蠕虫的污染,应加强人畜粪便的管理,加强对居民生产和生活环境卫生的整治,加大寄生虫病防治的宣教力度,有效控制寄生虫感染疾病传播。  相似文献   
9.
目的 探究患枯萎病菊花与健康菊花根际土壤微生物群落的差异。方法 以患病菊花植株和健康菊花植株根际土壤为研究材料,采用高通量测序技术对患病植株和健康植株样本的细菌16S rDNA和真菌内部转录间隔区(ITS)基因进行序列测定并进行数据分析。结果 枯萎病的发生降低了菊花根际土壤中细菌种群的丰富度和多样性程度,但对根际土壤中的真菌α-多样性无明显影响。菊花健康植株根际土壤细菌微生物中酸杆菌门、芽单胞菌门、硝化螺旋菌门占比高于患病植株,而变形菌门、拟杆菌门占比低于患病植株(P<0.05)。菊花患病植株根际土壤中镰刀菌属(Fusarium)真菌占比分别为27.49%,14.53%,11.94%,而健康植株镰刀菌属真菌占比分别为0.47%,1.01%,0.67%。菊花患病植株根际土壤中会出现细菌性致病菌果胶杆菌属(Pectobacterium)和菊迪基氏菌属(Dickeya),而健康植株根际土壤中硝化类细菌、解毒类细菌、光合细菌等丰度高于患病植株。结论 患有枯萎病地块菊花植株根际土壤微生物中细菌的物种多样性和丰富度降低,并大量富集镰刀菌属致病真菌和积累果胶杆菌属与菊迪基氏菌属致病细菌,而健康菊花植株根际土壤微生物有益菌占比明显高于患病植株。  相似文献   
10.
钝化剂对土壤重金属镉含量及其在川麦冬中累积的影响   总被引:1,自引:0,他引:1  
目的 通过盆栽实验,综合评价不同钝化材料对土壤镉的钝化以及对川麦冬Cd含量降解的影响。方法 以一年生川麦冬为供试材料,采用土壤盆栽实验方法研究了钝化材料汉白玉(Ar)、秸秆生物炭(Br)、粉煤灰(Fh)、菌渣(Me)、硅藻土(Dm)对土壤总Cd、有效Cd和川麦冬各部Cd吸收累积的影响。结果 2种Cd污染程度土壤,不同钝化材料处理下均能提高土壤pH值;土壤阳离子交换量均极显著高于对照组,与土壤pH值成正相关;土壤总Cd含量和土壤有效Cd、麦冬地上部和地下部Cd含量较对照均极显著降低。综合各项指标发现,Ar对重金属Cd的钝化效果最佳,Br和Fh效果其次。结论 结合盆栽实验结果来看,Ar、Br、Fh、Me和Dm能够有效降低土壤总Cd含量、有效Cd含量和麦冬各部Cd含量,还能促进麦冬的稳收增产;综合分析,Ar、Fh和Br对重金属Cd钝化效果最好,可作为涪城麦冬种植区土壤钝化修复首选材料。  相似文献   
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