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991.
Ecosystem Services of Woody Crop Production Systems 总被引:1,自引:0,他引:1
Ronald S. ZalesnyJr John A. Stanturf Emile S. Gardiner James H. Perdue Timothy M. Young David R. Coyle William L. Headlee Gary S. Bañuelos Amir Hass 《Bioenergy Research》2016,9(2):465-491
Short-rotation woody crops are an integral component of regional and national energy portfolios, as well as providing essential ecosystem services such as biomass supplies, carbon sinks, clean water, and healthy soils. We review recent USDA Forest Service Research and Development efforts from the USDA Biomass Research Centers on the provisioning of these ecosystem services from woody crop production systems. For biomass, we highlight productivity and yield potential, pest susceptibility, and bioenergy siting applications. We describe carbon storage in aboveground woody biomass and studies assessing the provision of clean and plentiful water. Soil protection and wildlife habitat are also mentioned, in the context of converting lands from traditional row-crop agriculture to woody production systems. 相似文献
992.
993.
Janaína Marques de Almeida Vanderlei Aparecido de Lima Patrícia Carla Giloni de Lima Adriana Knob 《Bioenergy Research》2016,9(3):701-710
Efficient, low-cost enzymatic hydrolysis of lignocellulosic biomass is essential for cost-effective production of bioethanol. The aim of this study was to establish a fungal fermentation-based strategy for the economic enzymatic conversion of pineapple peel into fermentable sugars. Trichoderma viride was grown on passion fruit peel in order to improve its β-glucosidase production, and a crude extract was then used to hydrolyze pineapple peel. The effects of medium pH, cultivation time, and passion fruit peel concentration on β-glucosidase production were evaluated using a central composite rotational design (CCRD) combined with response surface methodology (RSM). Optimal β-glucosidase activity of 2.40 U mL?1 was found after 6.5 days of cultivation in medium at pH 6.0, containing 2.0 % passion fruit peel. Saccharification of pineapple peel was also optimized by RSM and CCRD with respect to pH, temperature, β-glucosidase concentration, and reaction time and proceeded optimally at pH 4.0, 55 °C, with a β-glucosidase loading of 31.25 U g?1 dry feedstock and 75 h of reaction. Under these conditions, T. viride crude extract hydrolyzed pineapple peel with a glucose yield of 65.3 %. This study therefore presents passion fruit peel as an attractive raw material for the production of β-glucosidases. In addition, it describes an improved, effective, and low-cost enzymatic method for the production of fermentable sugars from pineapple peel, an abundant and inexpensive agro-industrial waste. 相似文献
994.
Chang Geun Yoo Hoon Kim Fachuang Lu Ali Azarpira Xuejun Pan Kyeong Keun Oh Jun Seok Kim John Ralph Tae Hyun Kim 《Bioenergy Research》2016,9(1):67-76
Physicochemical characteristics of corn stover pretreated by soaking in aqueous ammonia (SAA) and low-moisture anhydrous ammonia (LMAA) were compared and investigated. The glucan digestibility of the treated biomass reached 90 % (SAA) and 84 % (LMAA). The LMAA pretreatment enhanced the digestibility by cleaving cross-linkages between cell wall components, whereas the SAA pretreatment additionally improved the digestibility by efficiently removing a major portion of the lignin under mild reaction conditions without significant loss of carbohydrates. Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), and gel permeation chromatography (GPC) revealed the structural and chemical transformations of lignin during the pretreatments. Both pretreatments effectively cleaved ferulate cell wall cross-linking that is associated with the recalcitrance of grass lignocellulosics toward enzymatic saccharification. Extracted lignin from SAA pretreatment was extensively depolymerized but retained “native” character, as evidenced by the retention of β-ether linkages. 相似文献
995.
996.
Shoji Kawamura 《Genes & genomics.》2016,38(9):779-791
Color provides a reliable cue for object detection and identification during various behaviors such as foraging, mate choice, predator avoidance and navigation. The total number of colors that a visual system can discriminate is largely dependent on the number of different spectral types of cone opsins present in the retina and the spectral separations among them. Thus, opsins provide an excellent model system to study evolutionary interconnections at the genetic, phenotypic and behavioral levels. Primates have evolved a unique ability for three-dimensional color vision (trichromacy) from the two-dimensional color vision (dichromacy) present in the majority of other mammals. This was accomplished via allelic differentiation (e.g. most New World monkeys) or gene duplication (e.g. Old World primates) of the middle to long-wavelength sensitive (M/LWS, or red–green) opsin gene. However, questions remain regarding the behavioral adaptations of primate trichromacy. Allelic differentiation of the M/LWS opsins results in extensive color vision variability in New World monkeys, where trichromats and dichromats are found in the same breeding population, enabling us to directly compare visual performances among different color vision phenotypes. Thus, New World monkeys can serve as an excellent model to understand and evaluate the adaptive significance of primate trichromacy in a behavioral context. I shall summarize recent findings on color vision evolution in primates and introduce our genetic and behavioral study of vision-behavior interrelationships in free-ranging sympatric capuchin and spider monkey populations in Costa Rica. 相似文献
997.
In the present study, seven galacturonosyltransferase-like (GATL) genes (OsGATLs) in rice (Oryza sativa L.) were genome-widely identified and the chromosomal locations and the gene structures of which were characterized. Under normal condition, OsGATL2 and OsGATL3 are highly expressed in root, while OsGATL4 is highly expressed in stem and leaf. Many cis-elements related to stress response and plant hormone were found in the promoter sequence of each OsGATL. The expression patterns of these OsGATL genes under treatment with abscisic acid (ABA), drought and low temperature were assessed by qRT-PCR. The expression levels of most OsGATLs significantly increased following the treatments with drought or low temperature. In addition, physicochemical properties of OsGATLs and phylogenetic analysis with GATL from rice and several other species were performed. 3D structures and protein–protein interaction (PPI) network of OsGATLs were further predicted by Swiss-model and STRING 9.0 database, respectively. The identification and bioinformatic analysis of GATL family in rice could provide reference data for further study on their biological functions, especially in the responsiveness to hormones and stress signaling. 相似文献
998.
Apolipoprotein C3 (ApoC3) plays a regulatory role in triglyceride (TG) metabolism. The higher level of TG can be a cause in pathogenesis of the vascular diseases or metabolic syndrome (MetS). In this study, we examined the associations of ApoC3 polymorphisms (?482C>T rs2854117 and 3238G>C rs5128) with Korean MetS patients. A total of 835 subjects were investigated, including 320 patients with MetS and 515 healthy subjects. The genotype analysis of the ApoC3 polymorphisms was performed by polymerase chain reaction-restriction fragment length polymorphism methods. Of the two polymorphisms studied, we observed a significant difference in the ?482C>T polymorphism between the MetS and control groups. The TT genotype of the ?482C>T polymorphism was associated with increased risk for MetS, compared with the controls (OR 1.627, 95 % CI 1.075–2.463, P = 0.021). The association was female-specific. No associations were found for the risk of MetS in the 3238G>C polymorphism. Haplotypes composed of two polymorphisms, however, were associated with MetS susceptibility in only male group. The 3238G>C polymorphism was significantly associated with TG levels (P = 0.013). Our data suggest that the ApoC3 ?482C>T polymorphism is associated with increased MetS susceptibility in the Korean population. 相似文献
999.
Yurong Jiang Shuijin Zhu Junjie Yuan Guolin Chen Guoquan Lu 《Genes & genomics.》2016,38(11):1013-1020
Betaine aldehyde dehydrogenase (BADH) is widely considered as a key enzyme in glycine betaine metabolism in higher plants. Several paralogous genes encoding different isozymes of BADH have been identified and characterized in some plants; however, until now, only limited information is available about BADH genes in quinoa (Chenopodium quinoa). Here, we report the molecular cloning, structural organization, phylogenetic evolution, and expression profile of a BADH gene (CqBADH1) from quinoa. The translated putative CqBADH1 protein included five conserved features of the ALDH Family 10. Comparisons between the cDNA and genomic sequences revealed that the CqBADH1 gene contained 15 exons and 14 introns. Comparative screening of introns in homologous genes demonstrated that the number and position of the BADH introns were highly conserved among the BADH genes in Amaranthaceae plants and in other more distantly related plant species. A phylogenetic analysis showed that CqBADH1 had the closest relationship with a protein from Atriplex canescens and belonged to the ALDH10 family. Expression profile analyses indicated that CqBADH1 was expressed only in root, and showed time-dependent expression profiles under NaCl-stress condition. Moreover, in quinoa, NaCl stress led to increased levels of CqBADH1 mRNA accompanied by the accumulation of glycine betaine. This is the first study to describe a BADH gene in quinoa. 相似文献
1000.
Chronic kidney disease (CKD) is characterized by a progressive loss of kidney function over a period of months or years. It is estimated that about 7.2 % of adults over the age of 30 have CKD worldwide. Although one of the major risk factors of CKD is family history, the heritability of CKD is not fully understood. It is also known that the diabetic condition is highly influential on the onset of CKD. To understand the genetic bases of CKD that remain unidentified, we performed genetic association analyses for kidney function-related traits such as blood urea nitrogen (BUN) and albumin in subjects stratified by diabetic status. In the discovery stage of the study, we used genome-wide scan data and clinical data in about 8800 subjects from the Korean Association Resource (KARE) project. Health2 study data comprising about 1800 subjects were used for the replication stage. Our two stage association analyses demonstrated that the LOC105374266 locus (rs9820070) showed strong evidence of association with BUN (P = 8.47 × 10?14) in nondiabetic normal subjects (n = ~4300). To extend our knowledge of the genetic determinants influencing kidney function, we also analyzed the association between kidney function-related traits and microRNA related variants. For this analysis, miRNA related SNPs were selected from KARE and Health2 cohort genotype data. Our study suggests the potential relevance of miRNA to the kidney function (miR-518b for BUN; miR-146a and miR-1295a for albumin) in Korean populations. 相似文献