浅论青年人才的职业流动

随着市场经济的发展 ,青年人才的流动日益频繁 ,并呈现出以下发展趋势 :青年人才向高科技产业流动 ;青年人才向经济发达地区和发达国家流动 ;青年人才向外资和私营企业流动。充分研究青年人才流动的原因及当前存在的问题 ,并加强对流动的正确引导 ,使青年人才流动向着更合理、更科学的方面发展     

胃萎汤对气虚血瘀证大鼠血液流变学指标的影响

目的 :观察胃萎汤对气虚血瘀证大鼠血液流变学指标的影响。方法 :用游泳劳损法制造气虚血瘀证大鼠模型 ,测定血液流变学指标。结果 :模型组大鼠的血液黏度明显增高 (P <0 .0 1或P <0 .0 5 ) ;胃萎汤大、中、小治疗组的大鼠血液流变学指标均有明显的改善 (P <0 .0 1或P <0 .0 5 )。结论 :胃萎汤通过改善气虚血瘀大鼠的血液流变学指标以发挥益气活血作用。     

Passive Drip Stain Formation Dynamics of Blood onto Hard Surfaces and Comparison with Simple Fluids for Blood Substitute Development and Assessment,

The spreading dynamics of blood dripping onto hard surfaces is compared to two spreading models. Samples of human blood, porcine blood, and Millipore^® water were dripped onto cardboard, foamcore, and glass surfaces in low velocity passive drip simulations. Final stain diameter, the total number of spines and scallops, and angle of impact were measured and analyzed. Spreading is best predicted by applying the concept of effective viscosity to the Scheller and Bousfield (R² = 0.91) and Roisman (R² = 0.89) spreading models. In the tested conditions, blood spreads with Newtonian tendencies; however, has quantifiable differences in stain appearance to Newtonian fluids like water. This is encouraging for the development of water‐based fluids as synthetic blood substitutes (SBSs). The work presents an assessment platform to quantify and score the performance of simple water‐based fluids using final stain diameter (6 points) and number of spines and scallops (6 points) at six dripping heights between 20 and 120 cm. The angle of impact of a stain alone is not a sensitive measure of SBS performance, but stain formation scores the SBS's performance with another 1 point. Together these features generate a quantitative relative ranking system, of a maximum possible 13 points, that can be used to support the use of a particular fluid for the creation of a drip stain. The performance of twenty simple fluids in the simulated dripping assessment test is described.     

Nitrate and Nitrite Determination in Gunshot Residue Samples by Capillary Electrophoresis in Acidic Run Buffer,

Simultaneous determination of nitrate and nitrite in gunshot residue has been conducted by capillary electrophoresis using an acidic run buffer (pH 3.5). In previously developed capillary electrophoretic methods, alkaline pH separation buffers were used where nitrite and nitrate possess similar electrophoretic mobility. In this study, the electroosmotic flow has been reversed by using low pH running buffer without any additives. As a result of reversing the electroosmotic flow, very fast analysis has been actualized, well‐defined and separated ion peaks emerge in less than 4 min. Besides, the limit of detection was improved by employing large volume sample stacking. Limit of detection values were 6.7 and 4.3 μM for nitrate and nitrite, respectively. In traditional procedure, mechanical agitation is employed for extraction, while in this work the extraction efficiency of ultrasound mixing for 30 min was found sufficient. The proposed method was successfully applied to authentic gunshot residue samples.     

Quantitative Differentiation of Bloodstain Patterns Resulting from Gunshot and Blunt Force Impacts

Bloodstain pattern analysis (BPA) provides significant evidentiary value in crime scene interpretation and reconstruction. In this work, we develop a quantitative methodology using digital image analysis techniques to differentiate impact bloodstain patterns. The bloodstain patterns were digitally imaged and analyzed using image analysis algorithms. Our analysis of 72 unique bloodstain patterns, comprising more than 490,000 individual droplet stains, indicates that the mean drop size in a gunshot spatter pattern is at most 30% smaller than the mean drop stain size in blunt instrument patterns. In contrast, we demonstrate that the spatial distribution of the droplet stains—their density as a function of position in the pattern—significantly differs between gunshot and blunt instrument patterns, with densities as much as 400% larger for gunshot impacts. Thus, quantitative metrics involving the spatial distribution of droplet stains within a bloodstain pattern can be useful for objective differentiation between blunt instrument and gunshot bloodstain patterns.     

Site‐, Technique‐, and Time‐Related Aspects of the Postmortem Redistribution of Diazepam,Methadone, Morphine,and their Metabolites: Interest of Popliteal Vein Blood Sampling

Sampling site, technique, and time influence postmortem drug concentrations. In 57 cases, we studied drug concentration differences as follows: subclavian vein‐dissection/clamping versus blind stick, femoral vein‐dissection/clamping versus blind stick, right cardiac chamber, and popliteal vein‐dissection and clamping only. Cases were distributed in group #1 (all cases with both techniques), group #2 (dissection/clamping), and group #3 (blind stick). Sampled drugs were diazepam, methadone, morphine, and their metabolites. To assess PMR, mean concentrations and ratios were calculated for each group. Time‐dependent variations of blood concentrations and ratios were also assessed. Results indicate that site, method, and time may influence postmortem distribution interpretation in different ways. Popliteal blood seems less subject to PMR. In conclusion, our study is the first to evaluate concurrently three main aspects of PMR and confirms that the popliteal vein may represent a site that is more resistant to the changes seen as a result of PMR.     

GC-MS/MS测定血液中巴比妥类安眠药物

建立GC-MS/MS测定血液中巴比妥类安眠药物的分析方法。方法通过固相萃取提取并富集血液样品中常见巴比妥类安眠药物,采用离子阱二级质谱定性并定量检测其含量,并优化萃取溶液pH值与气相色谱/二级质谱联用分析条件,对巴比妥类安眠药物进行定量分析。结果巴比妥类安眠药物检出限为0.04μg/mL～0.10μg/mL,回收率为80.3%～92.6%。结论该方法高效、简单,灵敏度高,可用于血液中巴比妥类安眠药物同时定性定量检测。     

Developmental Validation of RSID™-Saliva: A Lateral Flow Immunochromatographic Strip Test for the Forensic Detection of Saliva

Abstract:  Current methods for forensic identification of saliva generally assay for the enzymatic activity of α-amylase, an enzyme long associated with human saliva. Here, we describe the R apid S tain ID entification (RSID™-Saliva), a lateral flow immunochromatographic strip test that uses two antisalivary amylase monoclonal antibodies to detect the presence of salivary amylase, rather than the activity of the enzyme. We demonstrate that RSID™-Saliva is accurate, reproducible, and highly sensitive for human saliva; RSID™-Saliva detects less than 1 μL of saliva. The sensitivity of RSID^TM-Saliva allows investigators to sample a fraction of a questioned stain while retaining the majority for DNA-STR analysis. We demonstrate that RSID™-Saliva identifies saliva from a variety of materials (e.g., cans, bottles, envelopes, and cigarette-butts) and it does not cross-react with blood, semen, urine, or vaginal fluid. RSID™-Saliva is a useful forensic test for determining which evidentiary items contain saliva and thus may yield a DNA profile.     

气相色谱-串联质谱法测定血液中乙基葡萄糖醛酸苷

目的建立血液中乙基葡萄糖醛酸苷（ethyl glucuronide,EtG）的气相色谱-串联质谱（GC-MS/MS）测定方法。方法血液用乙腈沉淀蛋白,离心后,将上清液转移吹干,残留物经N,O-双（三甲基硅烷基）三氟乙酰胺衍生化,用GC-MS/MS进行检测。结果血液中EtG的检出限为0.05μg/mL,线性范围为0.1～10μg/mL（r=0.9999）。对送检案例血液检材进行EtG检测,效果良好。结论本方法适用于血液中EtG的检测。     

氨基黑显现常见客体上潜血足迹研究

目的研究氨基黑显现潜血足迹所适用的常见客体。方法选择14种常见客体,制作潜血足迹样本,用氨基黑进行显现。结果浅色非渗透性客体的效果优于其他客体。结论氨基黑可以很好的显出某些渗透性客体和非渗透性客体表面的潜血足迹。