The rheological properties of exudates from cured porcine muscle: effects of added non‐meat proteins

Meat exudates were collected from massaged cured porcine M semimembranosus using a model massaging unit. Exudates were used to observe changes in gelation properties due to the incorporation of commercially available non‐meat proteins. These included: soya isolate (90%), sodium (Na) caseinate (85%) and high gelling whey protein concentrates (WPCs, A‐35%, B‐75% and C‐β‐lactoglobulin (55%), as well as a regular 76% protein, WPC D. Compositional analysis ( n=6) showed that incorporation of non‐meat proteins significantly (P<0.05) increased the protein concentration of test exudates in all cases compared to controls. The viscoelastic properties of control and test meat exudate samples (n=6) were analysed using control stress rheology in oscillatory mode. All exudates were heated from 20 to 80°C at 1°C min⁻¹, and subsequently cooled after 30 min back down to 20°C at 1°C min ⁻¹. Addition of WPCs at a 1, 2 and 3% residual powder level and soya isolate at a 1% residual level, resulted in increased storage modulus G′ (Pa) values compared with controls. A 1% residual level of Na caseinate was detrimental to meat exudate gelation, resulting in lower final G′ (Pa) values than those observed for the control. © 1999 Society of Chemical Industry     

Sucrose esters of carboxylic acids in glandular trichomes ofSolanum berthaultii deter settling and probing by green peach aphid

Removal of type B trichome exudate fromSolanum berthaultii leaflets leads to a decrease in tarsal gumming and mortality and an increase in feeding by the green peach aphid,Myzus persicae. Type B trichome exudate of theS. berthaultii accession PI 473331 is composed of a complex of 3,3,4,6-tetra-O-acyl sucroses containing primarily short-chain branched carboxylic acids. The acyl constituents are primarily derived from 2-methylpropanoic, 2-methylbutyric, and 8-methylnonanoic acids but constituents derived fromn-decanoic and dodecanoic acids are also present. Sucrose esters inhibit settling and probing by aphids in glass feeding cages.     

The rheological properties of exudates from cured porcine muscle: effects of added carrageenans and whey protein concentrate/carrageenan blends

Meat exudates were collected from massaged cured porcine M semimembranosis using a model massaging unit. Exudates were used to observe changes in gelation properties of test exudates containing carrageenans and whey protein concentrate (WPC) and carrageenan blends. Three carrageenan powders iota (ι ), kappa (κ), as well as a kappa/locust bean gum mix, were assessed at a 1% residual level, both individually and as blends. WPCs assessed included high gelling A‐35, B‐75 and C 55% protein β‐lactoglobulin powders, as well as a regular 76% protein, WPC D. All WPCs were incorporated at a 2% residual powder level in the final meat. Treatment and control meat samples and resulting exudates were prepared in duplicate with analysis performed in triplicate. The viscoelastic properties of control and test meat exudate samples (n=6) were analysed using control stress rheology in oscillatory mode. All exudates were heated from 20 to 80°C at 1°C min⁻¹ , and subsequently cooled after 30 min back down to 20°C at 1°C min⁻¹. Combinations of high gelling WPCs, especially β‐lactoglobulin together with iota and kappa‐carrageenans A and B, were found to increase storage modules G′ (Pa) values when compared with control values. Significant (p<0.05) synergies were observed on blending high gelling WPCs with carrageenans A and B. © 1999 Society of Chemical Industry     

Phytotoxicity of sorgoleone found in grain Sorghum root exudates

Root exudates ofSorghum bicolor consist primarily of a dihydroquinone that is quickly oxidized to ap-benzoquinone named sorgoleone. The aim of this investigation was to determine the potential activity of sorgoleone as an inhibitor of weed growth. Bioassays showed 125M sorgoleone reduced radicle elongation ofEragrostis tef. In liquid culture, 50-M sorgoleone treatments stunted the growth ofLemna minor. Over a 10-day treatment period, 10M sorgoleone in the nutrient medium reduced the growth of all weed seedlings tested:Abutilon theophrasti, Datura stramonium, Amaranthus retroflexus, Setaria viridis, Digitaria sanguinalis, andEchinochloa crusgalli. These data show sorgoleone has biological activity at extremely low concentrations, suggesting a strong contribution toSorghum allelopathy.     

改进U型网络在视网膜病变检测中的应用研究

眼底视网膜血管分析和渗出物、出血点等主要病灶区检测是判断糖尿病性视网膜病变程度的重要方法。针对细微血管的分叉以及端点处分割效果不好、渗出物边界不明显以及出血点细小且分布零散不易分割等问题;提出一种改进U型网络;通过改进上下文提取编码模块;提取更丰富的高级别特征;并在特征编码阶段加入混合注意力机制（HAM）;突出细微血管以及病灶区特征;减小背景类和噪声影响。实验结果表明;提出的算法在眼底视网膜血管分割数据集DRIVE上的分割准确率、灵敏度、特异性和AUC值比U-NET、CE-NET等现有方法有一定提升;其中灵敏度相较CE-Net网络提升了0.014 6。在糖尿病性视网膜病变病灶区分割数据集DIARETDB1上;对渗出物和出血点的分割效果比U-NET、CE-NET等现有方法有较好的提升;能有效辅助医生诊断。     

生物质纤维医用敷料研究进展

针对当前传统医用敷料在患者伤口护理中出现的易感染、造成二次伤害等问题,结合生物质原料的生物可降解性、生物相容性、无毒性等特点,以及部分生物质纤维良好的吸湿性、抑菌性和一定的生物活性等性质,介绍了生物质纤维作为医用敷料的优势.概述了用于医用敷料的不同生物质纤维的制备方式,提出不同伤口定制化处理时适用的生物质纤维.归纳了近...     

Acyclohexanediones from setal exudate of Hawthorn lace bug nymphCorythucha cydoniae (Hemiptera: Tingidae)

The three major components of setal exudate from nymphs of the Hawthorn lace bug,Corythucha cydoniae, were identified as 3,6-dihydroxy-2-[1-oxo-6(E),8(E)-tetradecadienyl]cyclohex-2-en-1-one; 3,6-dihydroxy-2-[1-oxo-dodecanyl]-cyclohex-2-en-1-one; 3,6-dihydroxy-2-[1-oxo-8-dodecenyl] cyclohex-2-en-1-one. An additional 10 minor components were partially characterized.     

The Allelochemical Sorgoleone Inhibits Root H+-ATPase and Water Uptake

Sorghum plants inhibit the growth of some adjacent species. Root exudates from grain sorghum (Sorghum bicolor), consisting primarily of the quinone sorgoleone, are phytotoxic to several plant species, yet the mechanisms of growth inhibition remain to be fully explained. Disruption of electron transport functions in isolated mitochondria and chloroplasts has been reported as one explanation for growth inhibition. In the studies reported here, however, soybean seedlings grown in nutrient solution with 10, 50, or 100 microM sorgoleone showed no disruption of photosynthesis, as measured by leaf fluorescence and oxygen evolution, yet their mean leaf surface area was less when grown in 100 microM sorgoleone. Furthermore, in the presence of these same concentrations of sorgoleone, decreased nutrient solution use by soybean seedlings and decreased H+-ATPase activity in corn root microsomal membranes were observed. This suggests that impairment of essential plant processes, such as solute and water uptake, driven by proton-pumping across the root cell plasmalemma should also be considered as a mechanism contributing to observed plant growth inhibition by sorgoleone.     

有机氯农药污染土壤的植物修复机理研究进展

受有机氯农药污染土壤的植物修复是一项具有广泛应用前景的技术,对其修复机理的探讨有助于深入研究修复技术与应用推广。综合分析植物修复受有机氯农药污染土壤的机理,主要体现在:植物直接吸收和转运有机氯农药;植物释放分泌物去除有机氯农药;植物微生物联合体系对有机氯农药的转化。