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221.
Evaluating the durability of wood-based panels using internal bond strength results from accelerated aging treatments 总被引:1,自引:0,他引:1
In this study, the durability of wood-based panels was evaluated by comparing the internal bond (IB) strength retention after
five different laboratory-based accelerated aging tests with the IB retention after 5 years of outdoor exposure in Shizuoka
City. In each accelerated aging test, the IB retention of MDI-bonded panels showed high retention compared to other panels.
Outdoor exposure in Shizuoka City resulted in an IB retention value for particleboard (PF) and oriented strandboard (aspen)
of less than 10% after the 5-year exposure period. Medium-density fiberboards maintained their initial IB strength over the
same period. Calculation of the mean IB retention for all board types allowed comparison of the severity of aging between
the accelerated test methods and outdoor exposure. The ASTM six-cycle test method was the most severe among the standard treatment
cycles applied. 相似文献
222.
基于GIS的老挝-中国边境土地适用性评估 总被引:1,自引:0,他引:1
对老挝-中国边境林地使用变更进行了评估,并提出了茶叶的土地适用性。建立一个综合的基于GIS的分析系统(IGAS),该系统支持老挝-中国边境的林地使用和土地适用性的评估研究。采用多标准分析和系统动态技术评估林地使用和土地适用性,同时预测了潜在的茶叶用地。收集到的土地数据和数据分析表明,整体研究区域为10325.07 km2,当前的森林覆被由1992年的6337.33 km2(占61.38%)减少到2002年的5106.28 km2(占49.46%)。当前的森林主要被转为潜在林地和专门的永久农业用地,甚至国家生物多样性保护区域被转为橡胶种植区。林地使用转变的主要原因是贫穷。为了解决这个问题,根据多标准方法,我们对研究区域中适用茶叶种植土地提出了2种分类方案。 相似文献
223.
Preparation of silage is a common method to preserve green forage. It plays an important role in improving forage utilization, 相似文献
224.
Chitra Nehra Avinash Marwal Rakesh Kumar Verma Megha Mishra Pradeep Sharma 《The Journal of Horticultural Science and Biotechnology》2019,94(4):475-480
India is one of the world’s largest producers of papaya. Viruses, mainly begomoviruses and potyviruses, cause a significant loss in papaya production. The study described here has identified a new species of begomovirus and a new species of betasatellite infecting Carica papaya in India. The sequences of the begomovirus and betasatellite show 90.03% nucleotide sequence identity to an isolate of Radish leaf curl virus and 92.25% identity to an isolate of Tomato leaf curl betasatellite, respectively. Maximum likelihood phylogenetic tree of begomovirus sequence of isolate DP2 (KX353622) showed distant relationships with previously characterised begomoviruses. Recombination analysis proposed six recombination breakpoints in begomovirus genome with other geographical begomovirus isolates. 相似文献
225.
Sameer Kumar Chanda Venkata Ganga Rao Nadigatla Veera Prabha Rama Rachit K. Saxena Kulbhushan Saxena Hari D. Upadhyaya Moses Siambi Said N. Silim Kothapally Narasimha Reddy Anupama J. Hingane Mamta Sharma Shivali Sharma Stephen Dominic Lyimo Rose Ubwe Meshack Makenge Kananji Gad Paul Kiprotich Kimurto Manuel Amane Kennedy Kanenga Yuventino Obong Emanuel Monyo Chris Ojiewo Nagesh Kumar Mallela Venkata Jaganmohan Polineni Rao Prashanthi Lakkireddy Sudhakar Chourat Indraprakash Singh Sobhan Sajja Shruthi Hirikara Beliappa Rajeev K. Varshney 《Plant Breeding》2019,138(4):445-454
In the past five decades, constant research has been directed towards yield improvement in pigeonpea resulting in the deployment of several commercially acceptable cultivars in India. Though, the genesis of hybrid technology, the biggest breakthrough, enigma of stagnant productivity still remains unsolved. To sort this productivity disparity, genomic research along with conventional breeding was successfully initiated at ICRISAT. It endowed ample genomic resource providing insight in the pigeonpea genome combating production constraints in a precise and speedy manner. The availability of the draft genome sequence with a large‐scale marker resource, oriented the research towards trait mapping for flowering time, determinacy, fertility restoration, yield attributing traits and photo‐insensitivity. Defined core and mini‐core collection, still eased the pigeonpea breeding being accessible for existing genetic diversity and developing stress resistance. Modern genomic tools like next‐generation sequencing, genome‐wide selection helping in the appraisal of selection efficiency is leading towards next‐generation breeding, an awaited milestone in pigeonpea genetic enhancement. This paper emphasizes the ongoing genetic improvement in pigeonpea with an amalgam of conventional breeding as well as genomic research. 相似文献
226.
Pankaj Sharma Inderjit Singh Asmita Sirari Gaurav Khosla Gurjeet Singh Navkiran Kaur Ludhar Sarvjeet Singh 《Plant Breeding》2019,138(6):741-747
Inheritance of fertility restorer gene in pigeonpea was studied using F2 and BC1F1 populations derived from cross AL103A × IC245273. It was found to be controlled by single dominant gene. Out of 228 SSR primer pairs, 33 primer pairs showed parental polymorphism, while four primers were found polymorphic in bulk segregant analysis (BSA). These four primers viz., CcM 1615, CcM 0710, CcM 0765 and CcM 1522 were used for genotyping of F2 population and were found to be placed at 3.1, 5.1, 28.1 and 45.8 cM, respectively. Two of them, CcM 1615 and CcM 0710, evinced clear and unambiguous bands for fertility restoration in F2 population. The Rf gene was mapped on linkage group 6 between the SSR markers CcM 1615 and CcM 0710 with the distances of 3.1 and 5.1 cM, respectively. The accuracy of the CcM 1615 was validated in 18 restorers and six maintainer lines. The marker CcM 1615 amplified in majority of male restorer lines with a selection accuracy of 91.66%. 相似文献
227.
228.
Curcumin, a plant-derived polyphenolic compound, naturally present in turmeric (Curcuma longa), has been the subject of intensive investigations on account of its various activities. The implementation of safe, beneficial and highly functional compounds from natural sources in human nutrition/prevention/therapy requires some modifications in order to achieve their multi-functionality, improve their bioavailability and delivery strategies, with the main aim to enhance their effectiveness. The low aqueous solubility of curcumin, its rapid metabolism and elimination from the body, and consequently, poor bioavailability, constitute major obstacles to its application. The main objectives of this review are related to reported strategies to overcome these limitations and, thereby, improve the solubility, stability and bioavailability of curcumin. The effectiveness of curcumin could be greatly improved by using nanoparticle-based carriers. The significance of the quality of a substance delivery system is reflected in the fact that carrying curcumin as a food additive/nutrition also means carrying the active biological product/drug. This review summarizes the state of the art, and highlights some examples and the most significant advances in the field of curcumin research. 相似文献
229.
Raquel Lucas-González Manuel Viuda-Martos José Ángel Pérez-Álvarez Juana Fernández-López 《Plant foods for human nutrition (Dordrecht, Netherlands)》2017,72(1):67-73
The aim of the work was to study the influence of particle size in the composition, physicochemical, techno-functional and physio-functional properties of two flours obtained from persimmon (Diospyros kaki Trumb. cvs. ‘Rojo Brillante’ (RBF) and ‘Triump’ (THF) coproducts. The cultivar (RBF and THF) and particle size significantly affected all parameters under study, although depending on the evaluated property, only one of these effects predominated. Carbohydrates (38.07–46.98 g/100 g) and total dietary fiber (32.07–43.57 g/100 g) were the main components in both flours (RBF and THF). Furthermore, insoluble dietary fiber represented more than 68% of total dietary fiber content. All color properties studied were influenced by cultivar and particle size. For both cultivars, the lower particle size, the higher lightness and hue values. RBF flours showed high values for emulsifying activity (69.33–74.00 mL/mL), while THF presented high values for water holding capacity (WHC: 9.47–12.19 g water/g sample). The bile holding capacity (BHC) and fat/oil binding values were, in general, higher in RBF (19.61–12.19 g bile/g sample and 11.98–9.07, respectively) than THF (16.12–12.40 g bile/g sample and 9.78–7.96, respectively). The effect of particle size was really evident in both WHC and BHC. Due to their dietary fiber content, techno-functional and physio-functional properties, persimmon flours seem to have a good profile to be used as potential functional ingredient. 相似文献
230.
Ana E. González-Santiago Belinda Vargas-Guerrero Pedro M. García-López Alma L. Martínez-Ayala José A. Domínguez-Rosales Carmen M. Gurrola-Díaz 《Plant foods for human nutrition (Dordrecht, Netherlands)》2017,72(2):134-140
Lupinus albus seeds contain conglutin gamma (Cγ) protein, which exerts a hypoglycemic effect and positively modifies proteins involved in glucose homeostasis. Cγ could potentially be used to manage patients with impaired glucose metabolism, but there remains a need to evaluate its effects on hepatic glucose production. The present study aimed to analyze G6pc, Fbp1, and Pck1 gene expressions in two experimental animal models of impaired glucose metabolism. We also evaluated hepatic and renal tissue integrity following Cγ treatment. To generate an insulin resistance model, male Wistar rats were provided 30% sucrose solution ad libitum for 20 weeks. To generate a type 2 diabetes model (STZ), five-day-old rats were intraperitoneally injected with streptozotocin (150 mg/kg). Each animal model was randomized into three subgroups that received the following oral treatments daily for one week: 0.9% w/v NaCl (vehicle; IR-Ctrl and STZ-Ctrl); metformin 300 mg/kg (IR-Met and STZ-Met); and Cγ 150 mg/kg (IR-Cγ and STZ-Cγ). Biochemical parameters were assessed pre- and post-treatment using colorimetric or enzymatic methods. We also performed histological analysis of hepatic and renal tissue. G6pc, Fbp1, and Pck1 gene expressions were quantified using real-time PCR. No histological changes were observed in any group. Post-treatment G6pc gene expression was decreased in the IR-Cγ and STZ-Cγ groups. Post-treatment Fbp1 and Pck1 gene expressions were reduced in the IR-Cγ group but increased in STZ-Cγ animals. Overall, these findings suggest that Cγ is involved in reducing hepatic glucose production, mainly through G6pc inhibition in impaired glucose metabolism disorders. 相似文献