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Expression of an endoglucanase from Tribolium castaneum （TcEG 1 ） in Saccharomyces cerevisiae

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Insect Science 2014年第5期21卷 609-618页

作者： Derek Shirley cris Oppert Todd B. Reynolds Bethany Miracle Brenda Oppert William E. Klingeman Juan Luis Jurat-Fuentes Department of Entomology and Plant Pathology University of Tennessee Department of Microbiology University of TennesseeKnoxville TN 37996 USDA-Agricultural Research Service Center for Grain and Animal Health Research Manhattan KS 66502 Department of Plant Sciences University of Tennessee Knoxville TN 37996 USA

Insects are a largely unexploited resource in prospecting for novel cellulolytic enzymes to improve the production of ethanol fuel from lignocellulosic biomass. The cost of lignocellulosic ethanol production is expected to decrease by the combination of cellulose degradation （saccharification） and fermentation of the resulting glucose to ethanol in a single process, catalyzed by the yeast Saccharomyces cerevisiae transformed to express efficient cellulases. While S. cerevisiae is an established heterologous expression system, there are no available data on the functional expression of insect cellulolytic enzymes for this species. To address this knowledge gap, S. cerevisiae was transformed to express the full-length cDNA encoding an endoglucanase from the red flour beetle, Tribolium castaneum （TcEG 1）, and evaluated the activity of the transgenic product （rTcEG 1）. Expression of the TcEG1 cDNA in S. cerevisiae was under control of the strong glyceraldehyde-3 phosphate dehydrogenase promoter. Cultured transformed yeast secreted rTcEG1 protein as a functional β-1,4-endoglucanase, which allowed transformants to survive on selective media containing cellulose as the only available carbon source. Evaluation of substrate specificity for secreted rTcEG1 demonstrated endoglucanase activity, although some activity was also detected against complex cellulose substrates. Potentially relevant to uses in biofuel production rTcEG1 activity increased with pH conditions, with the highest activity detected at pH 12. Our results demonstrate the potential for functional production of an insect cellulase in S. cerevisiae and confirm the stability of rTcEG1 activity in strong alkaline environments.

关键词： biofuels insect cellulase Saccharomyces cerevisiae Tribolium castaneum yeast

Improved allometric equations for tree aboveground biomass estimation in tropical dipterocarp forests of Kalimantan,Indonesia

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Forest Ecosystems 2017年第2期4卷 83-92页

作者： Solichin Manuri cris Brack Fatmi Noor'an Teddy Rusolono Shema Mukti Anggraini Helmut Dotzauer Indra Kumara Fenner School of Environment and Society The Australian NationalUniversityLinnaeus Way Building 141Canberra ACT2601Australia Dipterocarps Research Center Forest Research Development and Innovation AgencyMinistry of Environment and ForestryJl.AW SyahraniSamarindaEast KalimantanIndonesia Faculty of Forestry Bogor Agricultural UniversityJl Raya DarmagaKampus IPBBogor 16680Indonesia Forests and Climate Change Program Deutsche Gesellschafc fur Internationale Zusammenarbeit(FORCLIME-GIZ)Manggala Wanabakti BuildingBlock VII6th floorJakartaIndonesia Biodiversity and Climate Change Program Deutsche Gesellschafr fur Internationale Zusammenarbeit(BIOCLIME-GIZ)Manggala Wanabakti BuildingBlock VIL 6th floorJakartaIndonesia District Forestry and Plantation Service Jl.Antasarl No 4 Putussibaa Kapuas Hulu 78711West KalimantanIndonesia

Background： Currently, the common and feasible way to estimate the most accurate forest biomass requires ground measurements and allometric models.Previous studies have been conducted on allometric equations development for estimating tree aboveground biomass（AGB） of tropical dipterocarp forests（TDFs） in Kalimantan（Indonesian Borneo）.However, before the use of existing equations, a validation for the selection of the best allometric equation is required to assess the model bias and precision.This study aims at evaluating the validity of local and pantropical equations; developing new allometric equations for estimating tree AGB in TDFs of Kalimantan; and validating the new equations using independent datasets.Methods： We used 108 tree samples from destructive sampling to develop the allometric equations, with maximum tree diameter of 175 cm and another 109 samples from previous studies for validating our equations.We performed ordinary least squares linear regression to explore the relationship between the AGB and the predictor variables in the natural logarithmic form.Results： This study found that most of the existing local equations tended to be biased and imprecise, with mean relative error and mean absolute relative error more than 0.1 and 0.3, respectively.We developed new allometric equations for tree AGB estimation in the TDFs of Kalimantan.Through a validation using an independent dataset,we found that our equations were reliable in estimating tree AGB in TDF.The pantropical equation, which includes tree diameter, wood density and total height as predictor variables performed only slightly worse than our new models.Conclusions： Our equations improve the precision and reduce the bias of AGB estimates of TDFs.Local models developed from small samples tend to systematically bias.A validation of existing AGB models is essential before the use of the models.

关键词： Allometric equation Local and pantropical models AGB Model validation Destructive sampling Tropical dipterocarp forest

分子和异质化的双核Ir-Cp^*水氧化催化剂含EDTA或EDTMP作为桥接和锚定配体

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Science Bulletin 2020年第19期65卷 1614-1625,M0003页

作者： Chiara Domestici Leonardo Tensi Francesco Zaccaria Nade Kissimina Massimiliano Valentini Roberto D'Amato Ferdinando Costantino cris.iano zuccaccia Alceo Macchioni Department of Chemistry Biology and BiotechnologyUniversity of Perugia and CIRCCPerugia 06123Italy école Supérieure d'Ingénieurs de Rennes University of Rennes 1Rennes 35042France Department of Chemistry Sultan Qaboos UniversityMuscat 123Oman

开发高效的水氧化催化剂对于推动以生产可再生燃料为目标的可持续还原过程具有重要意义.本文报道了两个新型双核铱配合物(Ir-H4-EDTMP和Ir-EDTA)的合成和广泛表征,其中N,N,N',N'-乙二胺四乙酸(EDTA)及其类似物N,N,N',N'-乙二胺四(亚甲... 详细信息

开发高效的水氧化催化剂对于推动以生产可再生燃料为目标的可持续还原过程具有重要意义.本文报道了两个新型双核铱配合物(Ir-H4-EDTMP和Ir-EDTA)的合成和广泛表征,其中N,N,N',N'-乙二胺四乙酸(EDTA)及其类似物N,N,N',N'-乙二胺四(亚甲基膦酸)(EDTMP)充当两个片段Ir-Cp^*的κ^3-O,N,O-桥接配体.文章还展示了如何利用它们的羧酸盐和膦酸酯团的锚点在TiO2上异质化这些复合物.由此获得的混合材料(Ir-H4-EDTMP@TiO2和Ir-EDTA@TiO2)代表双核异质水氧化催化剂的罕见例子.由NaIO4引导的水氧化中测试了分子和异质化的催化剂,显示出高效率和活性.特别是,在效率、TOF和可回收性方面,杂化材料的性能明显优于单核配合物的类似材料.

关键词： Renewable fuels Water oxidation Homogeneous catalysis Heterogenized catalysts Organometallic chemistry Dinuclear complexes

Metrological Analysis of Sunflower Prototype

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Smart Grid and Renewable Energy 2015年第3期6卷 41-47页

作者： Hermes Jose Loschi Yuzo iano Rosivaldo Ferrarezi Neusa Rocha Ferrarezi Fabrizzio Daibert Conte Department of Communications Faculty of Electrical and Computer Engineering State University of Campinas (UNICAMP) Campinas Brazil

It is well known that the solar tracking systems can increase the efficiency of the photovoltaic (PV) panel by about 30 percent. However, these systems require precise control of their components, mainly of the equipment’s used for the measurement of energy. In this paper, a metrology analysis is conducted, through of the results obtained by Sunflower prototype. The Sunflower is a solar tracking system developed by H. J. Loschi. A tracking system through a microcontrolled timing logic, sending commands to a linear actuator that moves the system. The deductions, based on in research trials, confirms that the Sunflower prototype is more efficient in relation to fixed PV panels, it is possible to observe the difference in the efficiency of 31%, with a variation of ±0.8% (that depends the solar irradiation). The main purpose of this paper is to attest to the quality of the measurements carried out during the performance tests of the Sunflower prototype, evaluating the uncertainty of measurements collected through the measurements equipment, and, introducing methods to minimize uncertainties of measurement equipment in the PV systems.

关键词： Photovoltaic-PV Tracking Metrological Sunflower Prototype

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初冬暖日杨柳轻摇

数字生活 2002年第12期 38-43页

作者： cris

习惯用姓名去判断一个人,揣摩那简单排列的几个汉字背后,所隐含的立体而丰富的性情。杨柳便是如此,有着想象中细腻飘摇的灵气,却没有预料中娇揉造作的文弱。她带着时尚的气息,青春的活力,舞动在这难得一见的冬日暖阳中伴随钟爱的音乐坚... 详细信息

习惯用姓名去判断一个人,揣摩那简单排列的几个汉字背后,所隐含的立体而丰富的性情。杨柳便是如此,有着想象中细腻飘摇的灵气,却没有预料中娇揉造作的文弱。她带着时尚的气息,青春的活力,舞动在这难得一见的冬日暖阳中伴随钟爱的音乐坚守自己的像在《沙》中写到的:她并不绝望，因为她知道,另一粒沙在海底，痴痴地而永远地等待着她……

关键词：暖日杨柳初冬

A Review on Photovoltaic Systems: Mechanisms and Methods for Irradiation Tracking and Prediction

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Smart Grid and Renewable Energy 2015年第7期6卷 187-208页

作者： Hermes José Loschi Yuzo iano Julio León Angelo Moretti Fabrizzio Daibert Conte Horácio Braga Department of Communications Faculty of Electrical and Computer Engineering State University of Campinas (UNICAMP) Campinas Brazil

Solar energy is the raw material and main source for several applications of renewable energy systems;thus, knowledge about the intensity of solar irradiation is essential for efficiency of these systems. Electric energy sources capable of meeting the growing demands of society with minimal impacts to the environment and high efficiency have been object of research in the last decade. In this context, the conversion of sunlight into electricity through photovoltaic cells has become one of the most encouraged and used resources in the world. However, the most unpredictable factor, which hampers capturing solar irradiation, preventing a proper conversion of sunlight into electricity, is the presence of clouds in the sky. Many methods of tracking and prediction of irradiation were proposed to increase efficiency in the production of energy by photovoltaic cells. This article presents an updated review on the mechanisms used for tracking and irradiation prediction, and their respective methods. It begins with a brief review on photovoltaic systems and classification of its mechanisms. Then, it presents a detailed overview on the evolution of mechanisms and their corresponding methods for tracking and irradiation prediction. Finally, the authors conclude with an analysis of performance efficiency of the mechanisms and their corresponding methods presented, describing the pros and cons of the most significant proposals for tracking and irradiation prediction.

关键词： Photovoltaic (PV) Tracking Irradiation Prediction Closed-Loop Open-Loop