Contribution of Lipids to Volatiles Generation in Extruded Corn-Based Model Systems

Volatile compounds generated by model systems of zein, corn amylopectin and corn oil extruded at barrel temperatures of 120°C and 165°C were analyzed by GC and GU/MS. The largest quantities of lipid oxidation products were detected in systems containing all three components. In each system, the quantity of 2,4-decadienal was low relative to the quantities of hexanal, heptanal, and benzaldehyde. Identification of the Maillard reaction products, 2-methyl-3(or 6)-pen-tylpyrazine, 2-methyl-3(or 6)-hexylpyrazine, and 2,5-dimethyl-3-pen-tylpyrazine, suggested that lipid-derived aldehydes might be involved in the formation of substituted pyrazines.     

Endodermal sinus tumor and embryonal carcinoma of the ovary in a 53-year-old woman

BACKGROUND: Germ cell tumors, the most common ovarian malignancies in females under the age of 21, are rare in older women. We report an unusual case of a mixed embryonal carcinoma and endodermal sinus germ cell tumor in a perimenopausal patient and review the differential diagnosis and management of these malignancies with respect to age. CASE: A 53-year-old woman complaining of irregular menses and pelvic pain was found to have a large pelvic mass and a positive pregnancy test. Subsequent investigation revealed a large left adnexal mass, and an elevated beta-HCG and alpha-AFP. At laparotomy, a mixed germ cell tumor was found. The patient was treated with multiagent chemotherapy and currently is without evidence of disease. CONCLUSION: Although rare, the diagnosis of germ cell tumor should be considered in older women presenting with a large pelvic mass. The treatment and prognosis is similar regardless of age, except that reproductive-sparing surgery is not a priority in the older patient.     

Improvement of some pharmaceutical properties of drugs by cyclodextrin complexation. 4. Chlorpromazine hydrochloride

This study is a retrospective review of admissions, discharge records and blood culture results of neonates admitted to the Neonatal Intensive Care Unit of Korle Bu Teaching Hospital in Accra, from the first of January 1991 to the 31st of December 1992. During this two year period there were 443 positive blood cultures. Ninety percent of the blood cultures were from babies born in Korle Bu Teaching Hospital, thus making the incidence of neonatal bacteraemia 22.2 per 1000 live births. The overall mortality rate was 37.2%. Gram negative bacteria accounted for 70.9% and Gram positive bacteria for 29.1% of all neonatal bacteraemia. The most common isolates were Enterobacter species 29.6%; Streptococcus faecalis 14.4%; Staphylococcus aureus 10.8%; Acinetobacter species 9.5%; Klebsiella species 9% and Escherichia coli 8.8%. It is concluded that the incidence of neonatal bacterial sepsis is high in our hospital and is associated with a very high mortality rate. There is thus an urgent need to institute appropriate preventive and therapeutic measures.     

Dissociation of airway responsiveness and bronchoalveolar lavage (BAL) cell composition in sensitized guinea-pigs after daily inhalation of ovalbumin

The association between inflammatory cell influx, cell activation status and change of airway responsiveness to acetylcholine (ACh) after daily inhalation of ovalbumin (OA) in sensitized guinea-pigs was investigated. Starting 3 weeks after sensitization (OA at 50 mg/kg s.c.+i.p.) guinea-pigs were exposed daily to 2% OA (10 min; under cover of 0.5 mg/kg mepyramine i.p. 15 min before OA) for 2 weeks. Concentration-response curves (CRCs) for inhaled ACh were performed 24 h after the last OA-challenge and 24 h after another single OA-inhalation 1 week later. CRCs for inhaled ACh were neither affected 24 h after the last OA challenge (daily for two weeks) nor 24 h after another OA-inhalation one week later. In contrast, bronchoalveolar lavage (BAL) from repeatedly OA- sensitized/-challenged guinea-pigs immediately after the last CRC showed a significant increase of total cell count by about tenfold and increases in eosinophils by about 20-fold, neutrophils by 30-fold, macrophages by about fivefold and lymphocytes by about tenfold (P < 0.05, multiple Wilcoxon-test). In contrast, markers of cell activation (EPO, MPO) were significantly decreased (P < 0.05). Methylprednisolone almost completely prevented these changes in increased cell numbers and decreased cell activation (vs OA contr., P < 0.05). The lack of increased airway hyperresponsiveness despite a massive inflammatory cell influx suggests other factors controlling airway responsiveness than inflammation.     

Alcohol intake, Lewis phenotypes and risk of ischemic heart disease. The Copenhagen Male Study

In the Copenhagen Male Study we found an increased risk of ischaemic heart disease (IHD) in men with the Lewis phenotype Le(a-b-). This study investigated whether, within the group of Le(a-b-) men, any conventional risk factors modified their increased risk. Three thousand, three hundred and eighty-three men aged 53 to 75 years were examined in 1985/86 and their morbidity and mortality over the next four years recorded. Three hundred and forty-three men with cardiovascular diseases were excluded at baseline. Potential risk factors examined were: alcohol consumption, physical activity, tobacco smoking, serum cotinine, serum lipids, body mass index, blood pressure, hypertension, non-insulin dependent diabetes mellitus and social class. In eligible men with Le(a-b-), N = 280 (9.6%), alcohol was the only risk factor associated with risk of IHD. There was a significant inverse dose-effect relationship between alcohol consumption and risk. The age-adjusted p-values of trend tests were for risk of non-fatal + fatal IHD: p = 0.03; for risk of fatal IHD: p = 0.02. In eligible men with other phenotypes, N = 2,649 (90.4%) only a limited and non-significant negative association with alcohol. In Le(a-b-) men, a group genetically at increased risk of IHD, the risk was strongly and significantly negatively correlated with alcohol consumption.     

Flow and Flow Decay of Refractory Castables

Installation of refractory castables depend not only on flow,but also on how soon the flow is lost because of setting.The loss of flow(flow decay)has always been one of the main problems of refractory castable manufacturers,a problem that has not been too well described in literature.The flow decay has been studied for a castable system based on alumina,pointing out some general trends.The flow decay was found very temperature sensitive,being strongly accelerated by temperature increases.To compensate for excessive flow loss,a retarder like citric acid may be used.Thus flow decay was measured as a function of citric acid(retarder) addition at 35℃.     

高炉出铁沟用Al2O3-SiC-C浇注料流动性和流动性衰减的研究

通过调整氧化硅微粉加入量和活性氧化铝微粉的类型 ,研究了Al2 O3-SiC -C浇注料的流动性和流动性衰减以及可工作时间的变化。结果表明 :在浇注料流动性相近的情况下 ,随着氧化硅微粉加入量的增加 ,加水量显著降低 ;浇注料的流动性与所引入的活性氧化铝微粉的特性密切相关 ;氧化硅微粉加入量的增加有助于延长浇注料的可工作时间 ;浇注料流动性的衰减呈现出先缓慢后迅速降低直至凝结的特点 ,一般在可工作时间之后迅速凝结     

THE INFLUENCE OF RECYCLE ON MULTI-PASS LAMINAR COUNTERFLOW HEATERS OR COOLERS

A multi-pass laminar counterflow cooler or heater is an open duct divided into four subchannels with uniform wall temperature by inserting three impermeable sheets. Only the temperature of the flow stream varies along the subchannels. Improvements in heat transfer efficiency were investigated analytically with the use of eigenfunction expansions in the power series. The enhancement results in heat-transfer efficiency for two multi-pass devices (flow pattern A and flow pattern B) are represented graphically and compared with those in a single-pass device (without three impermeable sheets inserted) and those in a double-pass device (only one impermeable sheet inserted). Analytical results show that suitable impermeable-sheet position adjustments can effectively enhance heat transfer efficiencies for two multi-pass devices (flow pattern A and flow pattern B) compared with the efficiencies of single and double-pass devices.     

基于表面形貌的裂纹萌生阶段滑移带表征

目的研究WaspaloyTM镍基高温合金在裂纹萌生阶段的表面形貌特征,找出最优表面形貌参数用以表征此阶段的滑移带特征。方法对WaspaloyTM镍基高温合金试样先机械抛光,然后采用标准金相技术分别进行电解抛光和化学蚀刻,得到两种不同的表面状态。对试样进行低周疲劳试验获得疲劳寿命,并采用透射电子显微镜(TEM)和三维表面轮廓仪,观测分析WaspaloyTM镍基高温合金在电解抛光和化学蚀刻处理后的表面形貌以及裂纹萌生阶段的表面形貌和滑移带特征。对测得的表面形貌参数进行方差分析和自助抽样统计计算,找出最优参数。结果试样在经过电解抛光和化学蚀刻后,三维表面形貌S_a(表面算数平均偏差)分别是0.72 nm和13.3 nm,试样疲劳寿命分别为800和700。两种制备状态下的样品,算术平均高度增量(ΔS_a=S_a(N)-S_a(N0))的差异非常小,且ΔS_a随疲劳加载周期(N)的增加而增加,当N100后,ΔS_a随N增加的速率减小。结论电解抛光后的表面质量更好,且表面质量越好,疲劳寿命越高。ΔS_a与表面制备方法无关,ΔS_a越大,表面越粗糙。经方差分析和自助抽样法计算分析,表面最大峰值(Sp)是最优表面形貌参数,该参数可用于区分滑移带内的损伤晶粒和未损伤晶粒。     

淀粉制取高吸水树脂的研究

利用淀粉为原料,与丙烯酸接枝共聚制备了高吸水性树脂,考察了糊化温度、聚合反应时间、丙烯酸单体中和度等因素对接枝产物吸水性能的影响,并比较了吸自来水、蒸馏水及盐水情况。