Prevention of iron deficiency in infants by fortified milk. Field study of a low-fat milk

Healthy term infants were given a low-fat powdered milk fortified with 15 mg/100g of iron, as ferrous sulphate, for one year, starting at three months of age. The control group received non-fortified milk. A total of 510 infants entered the study, and 314 could be studied at the age of 15 months. Consumption of the fortified formulas was monitored through iron determinations in stools. Groups had a comparable hemoglobin concentration at the age of three months. Hemoglobin was higher in the fortified group at nine months (11.7 +/- 1.0 vs 11.4 +/- 1.1 g/dl, p less than 0.02), and 15 months (12.0 +/- 1.1 vs 11.4 +/- 1.2, p less than 0.001). The percentage of subjects with anemia (Hb less than 11.0 g/dl) was lower in the fortified group: 14.8% vs 27.7% of the controls at nine months and 7.0% vs 35.3% at 15 months. Percentages of subjects with iron deficiency (Fe/TIBC less than 9%) were lower in the fortified group: 28.0% vs 49.1% of the controls at nine months, and 20.0% vs 41.8% at 15 months. Although the fortified milk markedly improved iron nutrition, deficiency of this mineral was still high in the group receiving it. This was probably due to the low bioavailability of iron when administered with non-modified milks.     

Human milk in disease: Lipid Composition

Differences in the lipid composition of human milk have been described in maternal diseases known to affect fat metabolism. Diseases such as diabetes, cystic fibrosis, hypobetalipoproteinemia and Type I hyperlipoproteinemia affect the quantity and quality of human milk fat. Increased fatty acid chain elongation and changes in desaturation (especially Δ6 desaturase), as well as changes in lipid class composition, have been shown in diabetes and cystic fibrosis, whereas compensatory increases in medium-chain fatty acids have been described in hypobetalipoproteinemia and Type I hyperlipoproteinemia. It is important to realize that these observations were made either on single women or on very small groups of women. In infant diseases, such as breast milk jaundice and ectopic eczema, changes in polyunsaturated fatty acids in maternal milk have been described. Based on a paper presented at the Symposium on Milk Lipids held at the AOCS Annual Meeting, Baltimore, MD, April 1990.     

Development of tools to study lacto-N-biosidase: an important enzyme involved in the breakdown of human milk oligosaccharides

Milk and sugar? The elucidation of the catalytic mechanism and the development of the first known inhibitor for lacto-N-biosidases, which are important enzymes involved in the breakdown of human milk oligosaccharides, are described.     

WF油田强底水断块油藏开发规律研究及认识

为改善底水油藏开发效果,结合WF油田强底水断块油藏历年开发实践的基础上,分别对不同开发阶段的影响因素进行了详细分析,总结了强底水断块油藏的开发规律。通过计算临界产量和统计生产初期打开程度与含水的关系,早期应充分利用天然隔板,合理打开程度在30%左右;中期含水20%~80%时,合理控制生产压差;后期提掖稳产,晚期上返挖潜,确保了底水油藏的有效开发。该方法从不同生产阶段来分别制定对策,能充分挖掘油藏的生产潜力,来提高开发效果,其做法及经验可供同类型油藏开发参考借鉴。     

The validity of the compensation rule

Values of ΔH and τ_∞ for the mechanical relaxation times centred at ～ 700 s were obtained for isotactic polypropylene at three temperatures in the α-region by double T-jump. The values of ΔH and τ_∞ varied systematically in accordance with the compensation rule. The compensation temperature was observed to be T_c～240°C. It is shown that the compensation rule is in good agreement with the predictions of theories of Wert and Zener and of Eby.     

Visual acuity and blood lipids in term infants fed human milk or formulae

This multicenter, parallel group study determined plasma phospholipid and red blood cell (RBC) phosphatidylcholine and phosphatidylethanolamine fatty acids, plasma cholesterol, apo A-1 and B, growth and visual acuity (using the acuity card procedure) in term infants fed from birth to 90 d of age with formula containing palm-olein, high oleic sunflower, coconut and soy oil (22.2% 16∶0, 36.2% 18∶1, 18% 18∶2n−6, 1.9% 18∶3n−3) (n=59) or coconut and soy oil (10.3% 16∶0 18∶6% 18∶1, 34.2% 18∶2n−6, 4.7% 18∶3n−3) (n=57) or breast-fed (n=56) with no formula supplementation. Different centers in North America were included to overcome potential bias due to differences in n−6 or n−3 fatty acids at birth or in breast-fed infants that might occur in a single-site study. Plasma and RBC phospholipid docosahexaenoic acid (DHA, 22∶6n−3) and arachidonic acid (AA, 20∶4n−6), cholesterol and apo B were significantly lower in the formula- than breast-fed infants. There were no differences in looking acuity or growth among the breast-fed and formula-fed infants. No significant relations were found between DHA and looking acuity, or AA and growth within or among any of the infant groups. This study provides no evidence to suggest the formula provided inadequate n−6 or n−3 fatty acids for growth and looking acuity for the first 3 mon after birth.     

糖与人体健康的关系

糖是人体重要的能量输入性能源,糖经人体消化吸收以后很快转化为血糖,供应人体所需的能量,恢复体力、解除疲劳,其分解产物为二氧化碳和水,可以完全排出体外,在人体内不残留任何有害物质,因此,适当进食糖有助于健康与长寿。     

高品级人造金刚石合成的晶体学规律及分析

文章从晶体生长的一般规律出发,阐述了石墨与金刚石晶体结构的不同,论述了在金刚石晶体生长过程中金属触媒的作用机理以及高温高压对碳原子活化速度、结合速度、排逸速度及金刚石晶体生长速度与高品级金刚石生长的关系。     

The identity of the cholesteryl esters in human milk

Milk samples were collected from 11 mothers who were at least 4 weeks postpartum. The amounts of fat and the fatty acid compositions of cholesteryl esters (CE) and triacylglycerols (TG) in the milk were determined. The mean concentration of total milk lipid was 3.01 gm/100 ml of milk±.42 SD. The major fatty acids esterified with CE and TG were 16∶0,cis 18∶1 and 18∶2. The patterns were similar except for a greater proportion ofcis 18∶1 in the CE. The majortrans fatty acid detected was the 18∶1 isomer which accounted for 4.48% of the TG fatty acids and 2.96% of the CE fatty acids. Scientific Contribution No. 821, Storrs Agricultural Experiment Station, University of Connecticu, Storrs, CT. 06268     

Human milk fatty acid composition from nine countries varies most in DHA

Many published studies of breast milk FA composition are limited to populations from one or two countries. We aimed to examine the degree to which FA compositions vary across a number of diverse populations. Because diet and maternal adipose stores influence breast milk FA composition, differences in FA composition between groups most likely reflect habitual dietary differences. Approximately 50 breast milk samples (full breast expression) were collected from women in Australia, Canada, Chile, China, Japan, Mexico, Philippines, the United Kingdom, and the United States. The proportion of saturated FA was relatively constant among countries, with the exception of the Philippines, where levels of lauric and myristic acids were elevated (means greater than two times the mean of most other countries). Monounsaturated FA also varied little, with the exception of low levels of oleic acid in the Philippines and high levels of erucic acid in China. Although arachidonic acid (C20∶4n−6) levels were similar among all countries (means ranging from 0.36 wt% to 0.49 wt%), mean DHA (C22∶6n−3) levels ranged from 0.17 to 0.99 wt%, with the highest levels in Japanese milk and the lowest levels in Canadian and U.S. samples. The results of this study demonstrate that the proportion of saturated and monounsaturated FA are relatively constant across a large number of countries, whereas the level of some of the PUFA, especially DHA, are highly variable.     

Numerical and experimental methodology for the development of a new membrane prototype intended to microfiltration bioprocesses. Application to milk filtration

In tangential flow filtration, the non-uniform TransMembrane Pressure (TMP) on the membrane length produces a non homogeneous filtration cake, initiates process selectivity changes and modifies the permeate quality. The purpose of this study is to create a tubular ceramic membrane prototype with a more uniform TMP, intended to filtration of fouling fluids. The principle of this membrane structure is to waterproof the external membrane surface to limit flow circulation in the porous support of the membrane. The production was controlled by sizing «permeation vents». This development was achieved using a CFD modelling tool interacting with experiments. A preliminary modelling study was made with water. This work was afterwards applied to the industrial process of casein micelle separation from skim milk. The influence of operating conditions on the membrane hydrodynamics was highlighted. The modelling results were experimentally confirmed, with a discrepancy smaller than 3% and a reproducible water permeability of 2.3 L h⁻¹ bar⁻¹ for 1 mm-wide vent (TMP = 1 bar, T = 20 °C). Then, milk filtration experiments showed a production ratio milk/water equal to 1/2. The permeate quality parameters were studied and the fouling phenomena were taken into account. A parametric study led to the sizing of a final prototype. Its efficiency was experimentally evaluated.     

同系物的正常沸点与相对分子质量的经验公式

本文用Tb=A·M B·M/(C M)作为经验公式,描述了直链烷烃等23类同系物的正常沸点与其相对分子质量的变化趋势。在各种同系物所取范围之内,均取得满意的精度。利用本经验公式,估算同系物所取的范围之外的邻近化合物的正常沸点,外推结果的误差也不大。本经验公式也可作为同系物的其他物性与分子量关联的借鉴。     

纳滤膜在功能性低聚糖分离纯化中的应用研究进展

功能性低聚糖具有抗肿瘤、抗放射、抗凝血、消炎和调节免疫力等医疗保健作用,广泛应用于食品科学和生物医药等领域。纳滤作为一种高效的膜分离技术,在功能性低聚糖的分离与纯化中的应用得到越来越多的关注。本文分析了纳滤膜对功能性低聚糖的分离机理,综述了纳滤膜在功能性多糖分离纯化中的应用进展,讨论了纳滤分离过程的影响因素,主要包括功能性多糖料液的性质、膜过程的操作参数以及膜材料本身的性质等。其中,料液的性质主要体现在组成、浓度、黏度等方面;操作参数主要体现在压力、温度、膜面流速和pH等方面;而膜材料的性质主要体现在微结构和表面性质两个方面。最后,进一步指出纳滤膜技术用于功能性多糖分离纯化时在设备成本、膜材料及膜污染等方面存在的问题,并对未来纳滤膜技术在低成本专用膜材料及系统开发和膜污染控制方面的研究进行了展望。     

Human milk: Quantitative gas-liquid chromatographic analysis of triglyceride and cholesterol content during lactation

Gas-liquid chromatography has been used to follow changes in the triglyceride composition of human colostrum and milk from one donor during the first 10 days postpartum and to compare the compositions obtained with those at later stages of lactation. New triglycerides of low molecular weight appeared during the first 5 days postpartum. Lower molecular weight triglycerides (<C₄₈) continued to increase until the eighth day. Triglyceride C₄₈ and total cholesterol content remained almost constant during the period of the study. Comparison of triglyceride fatty acid composition on the third, sixth, and ninth days postpartum showed considerable specificity in all cases, but a tendency for randomization to occur as lactation proceeded. The advantage of triglyceride over fatty acid analysis for this type of investigation is that in the former, new molecules appear. In the latter, only changes in the proportions of fatty acids occur.     

塔河油田奥陶系碳酸盐岩岩溶缝洞型储层发育分布规律探索

塔河油田加里东中期和海西早期古岩溶作用及储层发育特征,在岩溶旋回划分、岩溶地貌分区及岩溶储层成因预测模式分析的基础上结合钻井揭示的储层类型进行了塔河油田岩溶储层的分区评价。     

Human milk fat substitutes: Advances and constraints of enzyme‐catalyzed production

The production of triacylglycerols (TAGs) with similar structures to the human milk fat TAGs is only possible using sn‐1,3 regioselective lipases as biocatalysts. The advances on the processes currently performed for the production of human milk fat substitutes (HMFS), namely the biocatalysts used, the best operation conditions, reactor types and operation modes, as well as the major drawbacks of these enzymatic systems, are addressed in this article.     

我国人造革合成革现状及发展趋势(二)

<正>三、PU合成革将成为人造革合成革的主流产品根据原材料的不同,人造革合成革可以分为PVC人造革和PU合成革。PU合成革无论是在功能性方面,还是在环保方面,都要优于PVC人造革。随着消费者对     

The role of amino acids in the autoxidation of milk fat

The effects of amino acids and their analogs on milk fat oxidation were examined under various conditions by measuring oxygen consumption and total unsaturated fatty acids. All the amino acids tested acted as antioxidants, characteristically extending the induction period (IP). Not only primary amino groups are responsible for the antioxidative activities of amino acids, but also the side-chain groups contribute, at least partially, to the protective effects of L-cysteine, L-tryptophan and L-tyrosine. In aqueous and HCL solutions, the antioxidative effects of L-alanine were significantly reduced. The freeze-dried L-lysine-HCL and L-alanine-HCL accelerated, while the corresponding control amino acids inhibited, milk fat oxidation.