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961.
962.
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
963.
964.
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
965.
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
966.
967.
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
968.
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
969.
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
970.
In northern China, large-spike wheat (Triticum aestivum L) is considered to have significant potential for increasing yields due to its greater single-plant productivity despite its lower percentage of effective tillers, and increasing the plant density is an effective means of achieving a higher grain yield. However, with increases in plant density, the amount of solar radiation intercepted by lower strata leaves is decreased and the rate of leaf senescence is accelerated. Row spacing can be manipulated to optimize the plant spatial distribution under high plant density, therefore improving light conditions within the canopy. Consequently, field experiments were conducted from 2010 to 2012 to investigate whether changes in row spacing under high plant density led to differences in canopy apparent photosynthesis (CAP), individual leaf photosynthesis and grain yield. Two different spike-type winter wheat cultivars, Jimai22 (a small-spike cultivar as a control cultivar) and Wennong6 (a large-spike cultivar), were grown at a constant plant density of 3,600,000 plants ha–1 (a relatively higher plant density) over a wide range of row spacing as follows: 5-cm row spacing (R0), 15-cm row spacing (R1), 25-cm conventional row spacing (R2), and 35-cm row spacing (R3). The two-year investigations revealed that increased row spacing exhibited a significantly higher light transmission ratio (LT), which improved light conditions within the canopy; however, excessive light leakage losses in R2 and R3 treatments were not favorable to improved irradiation energy utilization efficiency. Aboveground biomass accumulation was influenced by row spacing. Two spike-type wheat accumulated greater biomass under 15-cm row spacing compared to other row spacing treatments, although a markedly improved photosynthetic rate (PN), effective quantum yield of photosystem II (ΦPSII) and maximal efficiency of photosystem II photochemistry (Fv/Fm) in the penultimate and third leaves were observed in R2 and R3 treatments. At the same time, a longer duration of CAP and green leaf area was maintained in R1 during grain filling. Compared with conventional row spacing, Wennong6 in R1 treatment obtained 21.0% and 19.1% higher grain yield in 2011 and 2012, respectively, while for Jimai22 it increased by 11.3% and 11.4%, respectively. A close association of yield with CAP and LAI at mid-grain filling was observed. In conclusion, for the tested growing conditions, decreasing the row spacing to an optimal distance (15 cm) maintained a longer duration of LAI and CAP during grain filling, made a better coordination of group and individual leaf photosynthesis, and accumulated higher aboveground biomass, leading to a greater grain yield. In addition, Wennong6 had a more rational canopy architecture than Jimai22 (improved LT and higher LAI) and CAP under 15-cm row spacing, leading to a higher grain yield, which indicated that the large-spike type cultivar has the potential to obtain higher yields by increasing plant density through optimum row spacing allocation (15 cm). 相似文献