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101.
在组件GIS的二次开发应用中,数据的输入与修改是一个重要且必须考虑的问题.以ESRI公司的MapObjects为例,其本身对数据修改、添加等功能的实现比较复杂,而采用外部数据则容易多了.该文针对这一问题,分析讨论了MO中外部数据访问功能的理论基础与实现方法,并在Visual C++6.0编程环境支持下,运用ADO技术,以Excel为例,组合MapObjects提供的图层关联、图层搜索、图层输出等功能,将Excel工作簿中的单张表按字段匹配添加至图层内,并按指定的图层名保存下来,从而高效、便捷、快速、灵活地输入GIS属性数据,体现了组件GIS强大的开发潜力,成为MO数据管理功能扩展的有益补充.  相似文献   
102.
Five cultivars of bambara groundnut were selected on which to study the effects of germination and fermentation on their proximate composition. The cultivar that had the highest protein content was chosen to prepare unfermented and fermented milk. Standard assay techniques were adopted to determine the parameters selected for use. Germination caused a decrease in the protein, carbohydrate and starch; it increased sugar content, and had varied effects on the lipids contents of the dry samples. The anti-nutritional factor-tannin concentration was decreased. Germination and fermentation had varied effects on the nutrient compositions of the milk. Compared to the control, germination had the same effect as in the seeds. Fermentation further decreased some of the nitrogenous constituents, sugar and starch content of the milk and much more drastically the tannin content. Hydrolysis and other metabolic changes freed the nutrients from their bound forms while decreasing the quantity, but increasing the quality and availability of the nutrients.  相似文献   
103.
成膜预处理提高扇贝柱超声波辅助热泵干燥效率及品质   总被引:1,自引:1,他引:0  
热泵干燥(Heat Pump Drying,HPD)因条件温和、能效高,特别适用于水产品的干燥。但是,由于HPD温度低,导致干燥时间长、干制品品质劣变严重,限制了HPD在水产品中的应用。为了强化扇贝柱HPD效率,提高干制品品质,该研究首先采用超声波(Ultrasonic,US)预处理扇贝柱,然后再分别采用3种可食性膜(海藻酸钠(Sodium Alginate,SA),低甲氧基果胶(Low-Methoxy Pectin,LMP)和印度树胶(Gum Ghatti,GG))预处理,US处理后未经过成膜预处理的扇贝柱作为对照组(Control Group,CK),探究成膜预处理对扇贝柱US辅助HPD动力学及品质特性的影响。基于低场核磁共振(Low-Field Nuclear Magnetic Resonance,LF-NMR)技术,采用单变量线性(Univariate Linear,UL)模型和偏最小二乘回归(Partial Least Squares Regression,PLSR)模型量化扇贝柱LF-NMR弛豫参数与干制品含水率(Moisture Content,MC)和水分活度(Water Activity)的关系,以期监测扇贝柱HPD进程。研究结果表明:相比于CK,成膜预处理导致扇贝柱有效水分扩散系数(Effective Moisture Diffusivity)提高了1.32%~8.41%。SA和GG成膜预处理可以减缓扇贝柱干燥过程中不易流动水向结合水迁移的速率,同时增加了干燥过程中自由水的流动性,进而强化了干燥效率。相比于CK,SA和GG成膜预处理增加了扇贝柱硬度、弹性、内聚性和咀嚼性,降低了复水比、收缩率和总色差值;而LMP成膜预处理降低了硬度和总色差值。综合考虑,US-SA为扇贝柱US辅助HPD较适合的预处理方式。LF-NMR横向弛豫时间与大部分干制品品质之间具有显著(P<0.05)关联性。扇贝柱LF-NMR图谱中,当横向弛豫时间主峰<10 ms时,而且仅出现1个主峰,即可作为扇贝柱干燥终点。UL模型表明,MC和水分活度与不易流动水峰面积和总峰面积呈显著(P<0.05)正相关,与结合水峰面积呈显著(P<0.05)负相关。PLSR模型表明,以4个LF-NMR参数为变量的回归模型可高精度地预测MC和水分活度。该研究为扇贝柱热泵干燥增效、保质提供一种新型非热力预处理方式;同时,基于LF-NMR技术,为快速、无损监测扇贝柱热泵干燥进程提供理论依据和实践参考。  相似文献   
104.
为研究手掌参多糖对电离辐射损伤小鼠造血和抗氧化功能的治疗作用,本试验选用48只健康雌性昆明小白鼠,随机分为8组,分别为空白组,辐射组,手掌参多糖低、中、高给药组(150、300、600 mg·kg-1 组)和辐射低、中、高给药组;辐射组和辐射给药组分别用60Co-γ射线进行辐射,辐射剂量5.0 Gy(剂量率0.8 Gy·min-1)。分别在照射后 30 min内灌胃相应剂量的手掌参多糖和生理盐水(空白组、辐射组),连续5 d。末次灌胃后48 h内测定所有小鼠外周血细胞计数、脾脏指数、肝脏超氧化物歧化酶(SOD)活性、总抗氧化能力(T-AOC)、丙二醛(MDA)含量、骨髓DNA含量、骨髓嗜多染红细胞微核 (MN) 数目及脾脏T淋巴细胞亚群。结果表明,与空白组相比,给药组小鼠抗氧化能力和造血系统得到不同程度的改善,辐射组外周血细胞计数、脾脏指数、骨髓DNA含量、肝脏抗氧化能力及T淋巴细胞亚群极显著降低,MDA含量与MN数目显著升高; 与辐射组相比,辐射给药组小鼠脾脏指数和T-AOC、SOD活性极显著升高,DNA含量、外周血细胞计数也有所升高,CD3+、CD4+、CD8+ T淋巴细胞比率升高,MDA含量、MN数目显著降低。上述试验结果表明,手掌参多糖对60Co-γ射线照射造成的小鼠造血、抗氧化功能损伤具有治疗作用。本研究为手掌参多糖对辐射损伤的治疗提供了技术参考。  相似文献   
105.
A field investigation was conducted at the Indian Agricultural Research Institute's Research Farm during the kharif (wet) seasons of 2002 and 2003 in a split plot design with three replications, consisting of 27 treatments, namely, main plots: three varieties (PRH-10, Pusa Sugandh-3 and Pusa Basmati-1) and three plant spacings (20 × 10, 20 × 15 and 20 × 20 cm2) and sub-plots: three levels of nitrogen (0, 80 and 160 kg N ha?1). The research results indicated that aromatic rice hybrid PRH-10 produced 33 and 6%, respectively, more grain yield than that of Pusa Sugandh-3 and Pusa Basmati-1. The appreciable higher grain yield of PRH-10 over Pusa Sugandh-3 and Pusa Basmati-1 was due to considerable improvement in most of the yield attributing characters. Application of 160 kg N ha?1 recorded 23.7 and 26.1% more grain yield over no nitrogen application whereas it was 6.4 and 6.1% more over 80 kg N ha?1, respectively, during first and second year of the experimentation. Wider plant spacing of 20 × 20 cm2 and application of 160 kg N/ha recorded significantly higher hulling, milling and head rice recovery compared to closer spacing and zero nitrogen application.  相似文献   
106.

Background

Hamburger is the most consumed beef product in North America, but lacks in nutritional appeal due to its high fat content and high proportion of saturated fatty acids (SFA). Objectives of the present study were to improve the FA profiles of hamburgers made with perirenal fat (PRF) and subcutaneous fat (SCF) when feeding steers different diets along with examining differences in sensory attributes and oxidative stability. Diets included a control diet containing 70:30 red clover silage: barley based concentrate, a diet containing sunflower-seed (SS) substituted for barley, and diets containing SS with 15% wheat dried distillers’ grain with solubles (DDGS-15) or 30% DDGS (DDGS-30). Hamburgers were made from triceps brachii and either PRF or SCF (80:20 w/w).

Results

Perirenal fat versus SCF hamburgers FA had 14.3% more (P <0.05) 18:0, 11.8% less cis (c)9-18:1 (P <0.05), and 1.82% more total trans (t)-18:1 mainly in the form of t11-18:1. During sensory evaluation, PRF versus SCF hamburgers had greater (P <0.05) mouth coating, but the difference was less than one panel unit. Examining effects of steer diet within PRF hamburgers, feeding the SS compared to the control diet increased (P <0.05) t-18:1 by 2.89% mainly in the form of t11-18:1, feeding DGGS-15 diet led to no further changes (P >0.05), but feeding DDGS-30 diet reduced the proportions of (P <0.05) of t-18:1 chiefly t11-18:1. Feeding SS and DDGS diets had small but significant (P <0.05) effects on hamburger sensory attributes and oxidative stability.

Conclusions

Feeding high-forage diets including SS and 15% DDGS, and taking advantage of the FA heterogeneity between fat depots offers an opportunity to differentially enhance beef hamburgers with 18:2n-6 biohydrogenation products (i.e., t11-18:1) with potential human health benefits without compromising their sensory attributes and oxidative stability during retail display.  相似文献   
107.
The destruction of natural ecosystems is an important issue in many parts of the world. In the west of Iran, a vast area of the Zagros Mountain range is covered by typical vegetation including several rare plant species, of which many are currently considered endangered by anthropogenic activities. Despite the important role of soil seed banks to help conserve these degraded plant communities, the floristic studies in the Zagros forests have only focused on above- ground vegetation. In this study, the characteristics of soil seed banks and above-ground vegetation were examined at two forest sites: an undisturbed control (Un) and a disturbed (D) site. The objectives of this study were 1) to investigate the diversity of above-ground vegetation and soil seed banks in disturbed and undisturbed forests, 2) to examine the soil properties and the germination characteristics of the soil seed bank in disturbed and undisturbed oak forests and 3) to estimate the potential of soil seed banks in the restoration of disturbed sites. The results show that soil properties between Un and D sites were significantly different with higher values of pH, NH4-N, N~o,, CEC, OC, clay and canopy percentage in the Un site than in the D site. The Simpson diversity, Margalef richness and evenness indices differed significantly between sites, either for the soil seed banks or the above-ground vegetation. After a period of 26 weeks, the germination speed and the mean daily number of germinants were significantly different between Un and D sites. Without other conservation measures, soil seed banks alone cannot result in a full recovery after severe disturbances in the oak forests of Zagros.  相似文献   
108.
Oxygen (O2) is indispensable for aerobic respiration and cellular metabolism. In case of injury, reactive oxygen species are produced, causing oxidative stress, which triggers cell damaging chemical mediators leading to ischemic reperfusion injuries (IRI). Sufficient tissue oxygenation is necessary for optimal wound healing. In this context, several hemoglobin-based oxygen carriers have been developed and tested, especially as graft preservatives for transplant procedures. However, most of the commercially available O2 carriers increase oxidative stress and show some adverse effects. Interestingly, the hemoglobin derived from the marine lugworm Arenicola marina (M101) has been presented as an efficient therapeutic O2 carrier with potential anti-inflammatory, anti-bacterial, and antioxidant properties. Furthermore, it has demonstrated promise as a supplement to conventional organ preservatives by reducing IRI. This review summarizes the properties and various applications of M101. M101 is an innovative oxygen carrier with several beneficial therapeutic properties, and further research must be carried out to determine its efficacy in the management of different pathologies.  相似文献   
109.
Abstract

This paper examines how the United States and Canadian highbush and lowbush blueberry industries have changed over the last two decades. Production increases have been driven by a combination of changing consumer preferences for healthy foods and the development of new cultivars that have opened new production regions, expanded fresh market opportunities, and created new food products. Canada has found it advantageous and economical to invest its research effort in the development of the lowbush blueberry, exploiting its health protective properties. The Unites States has concentrated its research effort on highbush cultivars to lengthen the harvest window and promote diversification opportunities in the Southern United States. Highbush production expansion in the Pacific Northwest has relied very little on new cultivar development and improvements in yield but more on increases in cultivated area.  相似文献   
110.
耿艳艳  谢振飞  周羽  曾宪垠 《核农学报》2012,26(3):523-526,534
研究了姜辣素对60Coγ射线损伤小鼠造血和抗氧化功能的治疗作用。18只雌性健康昆明小鼠被随机分为3组,每组6只,分别为对照组、照射组、照射给药组。对照组不照射,连续灌胃5d蒸馏水;照射组和照射给药组分别用3Gy60Coγ射线进行照射,并分别在照射后30min内灌胃蒸馏水和姜辣素,连续5d。末次灌胃后48h内测定所有小鼠血液中白细胞(WBC)和红细胞(RBC)数量、脏器指数、肝脏超氧化物歧化酶(SOD)活性、总抗氧化能力(T-AOC)、丙二醛(MDA)含量及骨髓嗜多染红细胞微核(MN)数目。与对照组相比,照射组脾脏指数、WBC极显著降低(P<0.01),肝脏MDA含量、骨髓MN数目极显著升高(P<0.01);与照射组相比,照射给药组脾脏指数、T-AOC、SOD活性极显著升高(P<0.01),肝脏指数、WBC、RBC含量也有所升高,MDA含量、MN数目极显著降低(P<0.01)。结果表明,姜辣素对60Coγ射线照射造成的小鼠造血、抗氧化功能损伤具有治疗作用。  相似文献   
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