Foetal nutritional status and cardiovascular risk profile among children

OBJECTIVE: To estimate the impact of foetal nutritional status on cardiovascular risk among children with the Foetal Nutritional Status Index (FNSI), calculated by dividing the child's birth weight (BW, kg) by the mother's height (m2). DESIGN: Cross-sectional survey analysis. SETTING: A sample of children from the US Third National Health and Nutrition Examination Survey. SUBJECTS: A total of 3109 children who were 5-11 years of age and had data on BW and mother's height. Non-fasting blood samples were included. RESULTS: Overall, the FNSI was positively associated with BW and negatively associated with mother's height (P<0.0001). Within sex-specific quintiles of FNSI (third quintile as reference) adjusted for potential confounding variables, cardiovascular risk factors tended to be 'higher' in the lower quintiles for males while the opposite was true for females. Multivariate logistic regression analyses indicated that the odds for males in quintile 1 was 2.4 for having a low level of high-density lipoprotein cholesterol (P<0.01) and 2.1 for having a cluster of cardiovascular risk factors (P=0.01); for females, the odds of having a cluster of cardiovascular risk factors was approximately two times higher for those in the first and fifth quintiles, who also had a significantly higher prevalence of central obesity. CONCLUSIONS: The FNSI may be a potential proxy indicator of foetal nutritional status and it may be used to test specific hypotheses of whether foetal nutrition restriction or overnutrition programmes future cardiovascular risk.     

Dietary intake and body mass index in HIV-positive and HIV-negative drug abusers of Hispanic ethnicity

OBJECTIVE: Malnutrition in drug abusers has been attributed to poor diet. However, previous studies are conflicting. Many studies have not considered possible concurrent HIV disease. The purpose of this study was to determine the relationship between drug abuse and dietary intake in Hispanic Americans with and without HIV infection. DESIGN: Dietary intake was measured using 3-day food records and 24-hour dietary recalls in three groups: HIV-positive drug abusers, HIV-negative drug abusers and HIV-positive persons who do not use drugs ('non-drug abusers'). SETTING: The baseline data from a prospective cohort study of the role of drug abuse in HIV/AIDS weight loss and malnutrition conducted in Boston, Massachusetts, USA. SUBJECTS: The first 284 participants to enroll in the study. RESULTS: HIV-positive drug abusers had a body mass index (BMI) that was significantly lower than that of HIV-positive non-drug abusers. Reported energy, fat and fibre intakes did not differ between groups. All groups had median reported intakes of vitamin A, vitamin B6, vitamin B12, selenium and zinc that were in excess of the dietary reference values (DRI). Intakes of alpha-tocopherol were below the DRI, but did not differ from intakes of the general US population. However, increasing levels of drug abuse were associated with lower reported intakes of vitamin B6, vitamin B12, selenium and zinc. CONCLUSIONS: Overall, this study does not support the notion that dietary intake can explain the lower BMI of HIV-positive drug abusers. Further studies examining non-dietary determinants of nutritional status in drug abusers are warranted.     

Formation of humus profile in upland soils

It has generally been accepted that humus and its C/N ratio decrease with the depth of soil profile.     

alpha-Glucosidase inhibitory profile of catechins and theaflavins

To clarify the postprandial glucose suppression effect of flavonoids, the inhibitory effects of catechins and theaflavins against alpha-glucosidase (AGH) were examined in this study. It was initially demonstrated that theaflavins and catechins preferentially inhibited maltase rather than sucrase in an immobilized AGH inhibitory assay system. For the maltase inhibitory effects of theaflavins, the effects were observed in descending order of potency of theaflavin (TF)-3-O-gallate (Gal) > TF-3,3'-di-O-Gal > TF-3'-O-Gal > TF. This suggests that the AGH inhibition induced by theaflavins is closely associated with the presence of a free hydroxyl group at the 3'-position of TF as well as the esterification of TF with a mono-Gal group. In addition, the R-configuration at the 3'-position of TF-3-O-Gal showed a higher inhibitory activity than the S-configuration. As a result of a single oral administration of maltose (2 g/kg) in rats, a significant reduction in blood glucose level was observed at a dose of 10 mg/kg of TF-3-O-Gal, demonstrating for the first time that TF-3-O-Gal can suppress glucose production from maltose through inhibition of AGH in the gut.     

Isoflavone profile and biological activity of soy bread

The present study examines the ability of isoflavone extracts from whole soy bread and two soy bread fractions, crumb and crust, to modulate the proliferation of human prostate cancer PC-3 cells. Total isoflavone content in the two fractions of soy bread were similar (3.17 micromol/g dry basis). However, their conjugate patterns were altered. Both fractions of soy bread contained a similar level of isoflavone aglycones ( approximately 24%). Low concentrations of soy bread extracts increased PC-3 cell proliferation as much as 47% compared to untreated control. This proliferative effect in cell growth was reduced at higher extract concentration. Soy bread crust extract (10 mg/mL) reduced PC-3 cell proliferation by 15% compared to untreated control. Interestingly, wheat bread extracts increased cell proliferation at all concentrations tested. Although extracts from both breads possessed biological activity, only soy bread crust extract reduced PC-3 cell proliferation. This observation may be related to the presence of soy in this bread.     

The profile distribution of total and extractable copper in selected Nigerian soils

Abstract

The profile distribution of total, DTPA‐ and 0.1N HCl‐extractable Cu was determined in 11 Nigerian soil profiles formed from various parent materials including the coastal plain sands, shales, basalt, granite and banded gneiss.

Total Cu ranged from 7 to 72 ppm with a mean of 35 ppm₀ The soils formed from basalt had the highest values while those on coastal plains had the least content. Generally, there was a higher content in the subsoils than in the surface horizons. The total Cu significantly correlated with percent clay and the free oxide contents of Fe and Mn.

DTPA ‐ and 0.1N HCl‐extractable Cu ranged from 0.08 to 2.81 ppm and 0.10 to 7.78 ppm, respectively. Soils on metamorphic rocks gave the highest values of DTPA‐extractable Cu. The DTPA‐extractable Cu ‐was only related to pH but the acid extractable Cu was associated with total Cu, clay, free Fe₂O₃ and MnO₂ contents.     

The profile distribution of total and extractable zinc in selected Nigerian soils

Abstract

The profile distribution of total, DTPA‐ and 0.1 N HC1‐extractable Zn was determined in 11 Nigerian soil profiles formed on various parent Materials including the coastal plain sands, shales, basalt, granite and banded gneiss.

The total content ranged from 9 to 84 ppm. Generally soils developed on igneous rocks contained more Zn than those on sedimenatary deposits. Among the soils on sedimentary rocks, those on shale had more total Zn than those on sandstones. Total Zn was weakly correlated with organic matter but strongly associated vith clay content and free oxides of iron and manganese.

The amounts of Zn extracted by DTPA and 0.1 N HC1 ranged from 0.01 to 10.98 and from 0.23 to 6.25 ppm, respectively. The dilute acid generally removed more Zn from the soils than did the DTPA. The amounts extracted generally decreased vith depth especially vith DTFA extractant. Soils developed on basalt and shales contained the highest amounts of 0.1 N HCl‐extractable Zn while those on basement complex rocks gave the highest values of DTPA‐extractable Zn. Extractable Zn from soils on coastal plain sands remained relatively lev. The extractable Zn was more associated vith organic matter than vith clay content.     

Changes of protein profile in fresh-cut lotus tuber before and after browning

Browning is a critical problem, which often limits the shelf life and marketability in fresh-cut lotus tuber. Proteome level changes in response to the browning metabolism were investigated using two-dimensional electrophoresis (2-DE) and MALDI-TOF-TOF. A total of 34 functional protein spots were identified by comparing 2-DE protein patterns of fresh-cut lotus tuber before and after browning. These 34 identified proteins could be classified into 7 functional groups based on the NCBI database, that is, material and energy metabolism (35%), stress response (20%), respiration metabolism (12%), cell structure (12%), signal transduction (6%), gene expression regulation (6%), and unclassified proteins (9%). The group with the greatest difference in protein expression was related to material metabolism and regulation, reactive oxygen species metabolism, and respiratory control. The distinct proteins included universal stress protein (USP), superoxide dismutase (SOD), peroxidase (POD), ferritin, and ATPase.     

Bioavailability of triazine herbicides in a sandy soil profile

The bioavailability of atrazine was evaluated in a Danish soil profile (Drengsted) using a combination of soil sorption, transport and mineralisation methods as well as inoculation using Pseudomonas ADP. Sorption of atrazine decreased markedly with depth as indicated by K_d values of 5.2 l kg^-1 for the upper soil and 0.1 l kg^-1 for the subsoils. The transport of atrazine was evaluated using soil TLC plates and the resulting R_f values were 0.1 for the upper soil and 0.9 for the subsoil. Only a relatively small amount of atrazine leached through undisturbed soil columns taken from the upper 60 cm. Inoculating with Pseudomonas strain ADP (1᎒⁶ CFU g^-1 dry weight soil) revealed that the degradation of 0.01 ppm atrazine was fully completed (80% mineralisation) within 10 days in the subsoil, while it reached less than 15% in the upper soil. Over a period of 500 days, a total mineralisation of 37% of added atrazine in the upper soil was found (2 mg kg^-1 incubated at 20° C). However, in the subsurface soil where 0.02 mg kg^-1 of atrazine was incubated at 10°C, the degradation was slower, only reaching about 12%. Terbuthylazine mineralisation was found to be temperature-dependent and low (less than 5%) in the upper soil and very much lower in the subsoil. Desethylterbuthylazine was the most frequently found metabolite. Finally, Pseudomonas strain ADP inoculated into soils from different depths increased the mineralisation of terbuthylazine dramatically. Modelling using a "two-compartment model" indicated that desorption of terbuthylazine is the limiting step for its mineralisation.     

免耕对土壤剖面孔隙分布特征的影响

探明长期免耕措施对土壤孔隙特征、土壤结构及土壤水分参数等影响,可为阐明在小麦、玉米轮作过程中,长期进行免耕对土壤剖面物理特征的改善及其作用机理提供科学依据。采用CT扫描法定量分析了免耕和常规耕作0~100 cm土层土壤孔隙(80~1 000μm、1 000μm、80μm)的数目、孔隙度及孔隙在土壤剖面上的分布特征,同时采用常规方法测定了土壤大团聚体、土壤容重、有效水含量及饱和导水率等。结果表明:长期免耕不仅提高了土壤1 000μm、80~1 000μm、80μm孔隙数,且其孔隙度也相应提高,较常规耕作孔隙数分别提高55.3%、58.2%、57.9%,孔隙度分别提高97.4%、39.4%、72.6%。同时土壤孔隙形态也得到了改善,孔隙成圆率提高。对不同土层而言,免耕更利于提高0~25 cm土层80~1 000μm和80μm孔隙数以及0~45 cm土层1 000μm孔隙数,且显著提高了0~20 cm和25~40 cm土层1 000μm、80μm及0~20 cm土层80~1 000μm的土壤孔隙度。说明长期免耕对土壤剖面孔隙的分布产生一定影响。此外,免耕提高了0~25 cm土层土壤的有效水含量、0~55 cm土层饱和导水率和0.25 mm水稳性团聚体含量,降低了土壤容重,其作用深度在55 cm以上土层。通过CT扫描测得的土壤孔隙参数与常规方法测定的土壤物理参数之间存在极好的相关性,说明可从微观土壤孔隙特征来表征宏观的土壤物理性质。总之,长期免耕有利于改善土壤结构和土壤孔隙状况,提高土壤的渗透能力及土壤水分的有效性,促进作物的生长。     

Soil heterogeneity and profile development in a stratified gravel deposit in Ireland

The spatial variation in a soil section developed in a stratified, coarse-textured deltaic deposit is documented. Analytical and morphological data are presented for 8 A horizon, 19 B horizon and 6 C horizon samples taken from a 5-m section. The occurrence of a lithologic discontinuity at the A-B boundary as well as many stratigraphical discontinuities occurring diagonally across the B and C horizons is demonstrated. As a consequence a number of different soil profiles, which would place the soils in diverse soil orders or great groups in most classification systems, were found to exist side by side in the section studied. The problem of placing lateral boundaries to sampling sites in such materials is highlighted and the exclusive use of fine earth (<2 mm material) when assessing pedogenic trends and processes in coarse-textured materials is questioned.     

Earthworm feeding activity and development of the humus profile

Earthworm casts and digestive tract contents were simultaneously examined, using the same methods, in a recently formed humus profile in a mountain spruce forest. Earthworm species had distinct diets and an earthworm foodweb could be distinguished. Lumbricus terrestris and Aporrectodea icterica were distinct from the other species examined: the former to some extent as a litter consumer, and both species because they excavated mineral material which was deposited within new top layers of the mull humus. Aporrectodea nocturna and Aporrectodea caliginosa both had a non-specific soil feeding mode. Most of the species enriched the humus profile with amorphous organic matter finely incorporated within a mineral matrix. Besides different food selection, a network of burrows was produced as a consequence of the different burrowing behaviour of each earthworm species. Received: 2 January 1997     

田间土壤剖面中阿特拉津的迁移试验

为了评价阿特拉津的污染风险,采用原位试验法研究了土壤剖面中阿特拉津、Br-与水分耦合迁移特征.结果表明,施用阿特拉津24 h后,模拟降雨1 h,降雨量为40 mm的处理(Ⅰ)和80 mm的处理(Ⅱ)的土壤含水率随土层深度增加先减小后增加;而施用阿特拉津前模拟降雨1 h,降雨量为10mm,施用24 h后,模拟降雨1 h,降雨量为40 mm的处理(Ⅲ)和80 mm的处理(Ⅳ)的则呈"S"形变化.Br-与阿特拉津在0～10 cm土层的残留浓度最大,分别为1.40、1.09、0.62、0.52 mol/kg和0.82、0.74、0.54、0.29 靏/g.处理Ⅰ、Ⅱ的各土层中Br-与阿特拉津的变异较小.土壤溶液中阿特拉津的浓度随土层深度的增加而降低,表层(20 cm)土壤溶液中阿特拉津残留浓度为:处理Ⅰ＞处理Ⅲ＞处理Ⅱ＞处理Ⅳ.     

Distribution of nitrogen pools in the soil profile of undisturbed and reseeded grasslands

 This study evaluated the effect of cultivation and reseeding on the distribution and fate of soil mineral N (SMN), soluble organic N (SON) and potentially mineralisable N (PMN) in the soil profile of two long-term grasslands in the UK. Cultivation and reseeding significantly increased the total soluble N concentration (SMN plus SON) of the soil profile (0–90 cm), with over 50 mg SON kg^–1 observed. By contrast, the PMN pool was unaffected by cultivation and declined with increasing soil depth. The flush in SON and SMN observed in both soils disappeared within 1 year following cultivation. The fate of SON appeared to be dependent on soil type, with considerably more movement to deeper layers apparent in the profile of a silty clay loam (30% clay) than in a clay loam (49% clay). Mineralisation and/or immobilisation of SON in the topsoil probably accounted for the changes observed in the SON content of the clay loam. SON is an important N pool in grassland soils and cultivation has a significant impact on its release. Measurements of SON should therefore be included in studies of N cycling in agricultural cropping systems, so that full account may be taken of its potential as a source or sink of mobile N. Received: 17 February 1999     

控制暗管排水下土壤剖面水盐分布与变化特征

控制暗管排水可改变土壤水盐运移从而影响灌区盐渍化程度和土壤水分状况。为探讨土壤水盐分布与变化及其受控制排水与间距的影响,以河套灌区义长试验站暗管排水试区为对象,选取玉米生长期内典型灌溉周期开展研究。分析了控制排水及其间距变化下土壤水盐剖面静态分布与动态变化及灌水前后土壤水盐变异特性。结果表明：与自由排水比,控制排水提高了土壤剖面8.27%的相对含水率,增大了灌水期的含水率增幅,减少了间歇期的含水率降幅;控制排水还提高了土壤剖面盐分的分布均匀性,灌后的水平与垂向变异系数分别降低了45.88%和32.55%;同时,控制排水降低了土壤剖面36.73%的盐分含量,增大了灌水期29.17%的剖面脱盐区域,减少了间歇期14.29%的剖面积盐区域。控制排水基础上减少间距降低了灌水期的含水率增幅并增加了间歇期的含水率降幅,提高了灌前土壤盐分的水平分布均匀性却降低了灌后土壤盐分的水平分布均匀性。控制排水较高的盐分分布均匀性和脱盐效率及保墒效应有助于控制土壤次生盐渍化和提高农业用水效率。     

农田土壤颗粒组成及其剖面分层的空间变异分析

对60m55m的农田尺度上100个取样点土壤颗粒组成及剖面层次的空间变异性的传统统计分析表明,各属性的变异系数属中等强度。半方差函数模型均为球状模型,各属性具有一定的空间相关性,并表现有一定的各向异性。在对土壤颗粒组成及剖面层次空间分布趋势分析的基础上,根据半方差函数模型,对各属性选择不同趋势和异向性的普通Kriging内插值比较的结果表明,考虑变量在空间分布趋势和异向性的插值结果比不考虑要好。在以上分析基础上,利用Kriging内插值绘制各层深度和颗粒组成的等值线图,并分析了其空间分布规律。     

The weathering of biotite in a profile on gneiss in Malaysia

Biotite and its pseudomorphs were studied in a deep profile on gneiss from Malaysia. Alteration of biotite to halloysite takes place within a few centimeters of the fresh rock (at 18.5 m depth) in this humid tropical environment. The halloysite crystals are arranged parallel to the planar surface of the biotite (SEM studies) in the interlamellar spaces. There are zones in the profile where iron has accumulated and some of the iron crystallises as goethite on the edges and surfaces of the flakes. Once this coating has formed, further alteration is retarded as is shown by the fact that pseudomorphs with the coating contain both halloysite and vermiculite though the environment where they are present (position in the profile) is acidic and leaching.     

分根区垂向交替供水对玉米生长影响的研究

为探索1种新的节水灌溉技术——分根区垂向交替供水的节水增产效应，选用3种不同灌水方式(表面灌、下部灌、交替灌)和不同灌水周期(3 d、5 d、7 d)及不同灌水方式下的相同灌水量组合进行了盆栽玉米对比试验研究。结果表明，垂向交替供水是可行的，相同灌水量条件下交替供水对作物根系的生长有明显促进作用，使根系在土壤垂直剖面分布更为均匀。同时根系活力和吸收功能明显增强，整株作物长势呈现出苗壮根旺的特点。此外5 d的交替灌与3 d的表面灌相比，作物长势明显改善，且节水26%以上；7 d的交替灌与5 d的表面灌相比，作物长势无明显差异，但节水20%以上，而5 d的灌水周期是试验范围内交替灌应用时较为成功的方式。