Early home environment and changes in mental test performance in children from 6 to 36 months.

Administered the Bayley Scales of Infant Development at 6 mo and the Stanford-Binet Intelligence Scale at 3 yrs to 77 normal children. When each S was 6 mo old, the family was observed and interviewed using the Home Observation for Measurement of the Environment (HOME), a measure of the quality of stimulation in the early environment. A difference of 21 or more points between a S's 6-mo Bayley Mental Development Index score and 3-yr Stanford-Binet score was used to determine whether the S had increased, remained stable, or decreased in mental test performance. Multiple discriminant analyses were done using the 6 subscales of the HOME inventory to differentiate among increasers, nonchangers, and decreasers. Increases in test performance were related to 2 subscales, Maternal Involvement with Child and Provision of Appropriate Play Materials. Decreases were related to inadequate Organization of Physical and Temporal Environment. Results indicate that home environment may contribute to instability of performance on infant tests. Results are in agreement with the findings of R. B. McCall et al (see record 1975-04922-001) regarding gains for 21/2-17 yr olds, except that the parents' method of discipline may not be quite so important for infants. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Fatigue perturbed creep of pure aluminum at ambient temperatures

The creep of 99.999 pct pure aluminum subject to tension-tension cyclic stressing (dynamic creep) has been studied and compared to creep for the peak cyclic stress applied statically (static creep). The creep rate for a cyclic stress of 29.8 to 3.7 MPa was always found to be greater than the creep rate for static application of a stress of 29.8 MPa over the temperature range of 302 K to 348 K. The ratio of the dynamic creep rate to the static creep rate was found to increase with increasing strain and decreasing temperature. The apparent activation energy measured for dynamic creep was less than that measured for static creep. The substructure for dynamic creep is softer than for static creep and probably accounts for the accelerated creep rate and the lower observed activation energy.     

17Z-Tetracosenyl 1-glycerol ether from the spongesCinachyra alloclada andUlosa ruetzleri

The 1-glycerol ether of 17Z-tetracosenol has been identified as a major constituent of the dichloromethanesoluble extracts of two marine sponges,Cinachyra alloclada andUlosa ruetzleri. Spectral analysis and chemical degradations led to the assigned structure. Batyl alcohol was also found, in lesser quantities, inU. ruetzleri, but not inC. alloclada.     

Computer procedure for deriving ionospheric characteristic M(3000)F2 from h?(f) data

Standard procedures used at ionospheric observatories to determine the ionospheric characteristic M(3000)F2 by means of overlays or sliders applied to vertical-incidence ionograms are examined. Equations are presented to determine the corresponding values directly from numerical h?(f) data.     

骨蛋白酶解物的抗氧化作用

研究了骨胶原蛋白酶解物的总抗氧化能力、羟自由基(·OH)清除作用和抑制超氧阴离子自由基的能力.通过与谷胱甘肽(GSH)的比较发现,溶液质量浓度在100～150 mg/mL时,该骨胶原多肽的总抗氧化能力为GSH的71.92%.溶液质量浓度在2.5～20 mg/mL时,该多肽羟自由基清除作用为谷胱甘肽的1.36倍.溶液质量浓度为10～150 mg/mL时,多肽抑制超氧阴离子自由基的能力低于谷胱甘肽.     

超高压灭菌效果实验研究

超高压灭菌技术是一项具有广阔应用前景的食品加工新技术。本文以食品中常见的大肠杆菌、枯草芽孢杆菌为研究对象,通过实验对影响超高压灭菌效果的处理条件(压力、保压时间、pH值等)进行了考察与评价。实验结果表明:压力、保压时间对灭菌效果影响显著,随着压力的增大和时间的增长,细菌的死亡率增大。但当处理压力和和保压时间达到一定值后,它所对灭菌效果的影响趋于平缓。强的酸性和碱性环境中,即在低pH值和高pH值时,有利于超高压杀菌,在中性环境中,灭菌效果最差。同时,本文对超高压处理后大肠杆菌的活性进行了研究,得出大肠杆菌经超高压处理后活性降低的结论。研究结果对进一步优化超高压杀菌工艺具有一定的参考价值。     

卷烟主流烟气中焦油释放量的测量不确定度评定

目的评定卷烟主流烟气中焦油含量的测量不确定度,为测定主流烟气中焦油含量提供有效、可靠的测量数据。方法用吸烟机对卷烟主流烟气中的粒相成分进行捕集,应用气相色谱法对粒相成分中的烟碱和水分含量进行测定,再由总粒相物含量得出卷烟烟气中焦油含量。根据JJF(烟草)1-2007的指导方法,对上述焦油整个测量过程进行研究,系统分析得出不确定度来源和不确定度数学模型的基础上,确定焦油测量结果的置信区间,表述出了合成标准不确定和扩展不确定度。结果焦油测量不确定度的主要来源是由气相色谱测定曲线拟合及测试环境波动造成的,因此在检测过程中应尽量提高拟合曲线的线性度,并减小测试环境的波动,才能进一步的减小测量不确定度。结论该样品的焦油含量为8.98 mg/支,扩展不确定度为0.15 mg/支。     

Differentiation of Crude Lipopolysaccharides from Escherichia coli Strains Using Fourier Transform Infrared Spectroscopy and Chemometrics

Crude phenol‐phase extracts containing bacterial lipopolysaccharides (LPS) from 5 strains of Escherichia coli were investigated to differentiate the strains using Fourier transform infrared (FTIR) spectroscopy and multivariate statistical analysis. The strains used were E. coli K12, E. coli DH5α, E. coli O157:H7, E. coli O157:H12, and E. coli O157:H19. LPS‐containing extracts were isolated from each E. coli strain using a hot phenol‐water extraction procedure. The extracts were 1st analyzed by deoxycholic acid‐polyacrylamide gel electrophoresis and visualized by silver‐staining. Analysis of the extracts from E. coli K12 and E. coli DH5α showed rough‐type LPS on the lower half of the gel, whereas E. coli O157:H7, E. coli O157:H12, and E. coli O157:H19 yielded abundant smooth LPS (high‐molecular‐weight LPS that include the O‐polysaccharides). Spectra (4000 cm^‐1 to 700 cm^‐1) of crude E. coli LPS extracts and intact cells were collected using a FTIR spectrometer. Spectral data were compressed by principle component analysis and analyzed using canonical variate analysis (CVA) of 4000 cm^‐1 to 700 cm^‐1 or 1200 cm^‐1 to 900 cm^‐1 spectral regions. CVA showed better separation between strains using LPS extracts than intact cells in the 1200 cm^‐1 to 900 cm^‐1 spectral region. The same separation trend was found using Mahalanobis distances that quantified spectral differences between the E. coli strains, providing 80% and >95% correct classifications of intact cells and LPS extracts, respectively. This article is the first to report the successful differentiation of E. coli strains at a serotype level using FTIR spectra of bacterial phenol‐phase extracts (crude LPS preparations).     

酿酒酵母菌产谷胱甘肽的发酵条件研究

以从土壤中筛选出的酿酒酵母菌HSJB1为生产菌株,对影响其生物合成谷胱甘肽的摇瓶发酵条件进行了研究.优化的发酵培养基为:葡萄糖20g/L、硫酸铵5g/L、蛋白胨12.5g/L、磷酸二氢钾9g/L、硫酸镁1g/L、氯化钠0.2g/L、硫酸锌0.01g/L.优化的培养条件为:pH值为5、装液量30mL/250mL三角瓶、温度28℃、接种量110%.优化后谷胱甘肽的产量为59.60mg/L,比优化前提高了11.2%,生物量为4.25g/L,比优化前提高了11.8%.     

加速溶剂萃取-液相色谱法快速测定中药材地黄中 3, 4-苯并(a)芘残留

的 建立地黄中 3,4-苯并(a)芘的高压液相色谱快速测定方法。 方法 地黄样品用乙腈作提取剂经加速溶剂萃取, 中性氧化铝净化除去吸附杂质和色素后采用高压液相色谱-荧光检测法快速测定。 结果 3,4-苯并(a)芘在 1~20 ?g/kg 含量范围内线性关系良好, 线性方程为 Y=8.66e3X 4.11 e3, 相关系数为 0.999。本方法的定量限为 1 ?g/kg, 在 1、 5、 10 μg/kg 三个加标水平下, 加标回收率为 87.0%~93.1%, 相对标准偏差为 7.7%~14.3% (n=6)。结论 该方法简便快速、灵敏可靠, 适用于原地黄中中药材生、熟地黄中 3,4-苯并(a)芘的快速检测。