25 مقاله برتر علوم کشاورزی و زیست شناسی

در ادامه 25 مقاله برتر ژورنال ساینس دایرکت (ScienceDirect) از تاریخ آوریل تا جوئن 2015 را به شما محققین عزیز معرفی می کنیم.

ژورنال ساینس دایرکت مقاله های برتر تمام شاخه های علمی را به صورت دوره ای معرفی می کند و مقالاتی که در ادامه مشاهده می کنید در حوزه علوم کشاورزی و زیست شناسی به عنوان مقالات برتر برگزیده شده اند.

 

عنوان مقاله به انگلیسی: DPPH antioxidant assay revisited

عنوان مقاله به فارسی: بازبینی روش  DPPH در سنجش آنتی اکسیدان

کلمات کلیدی مقاله: DPPH،  دي ﻓﻨﯿﻞ ﭘﯿﮑﺮﯾﻞ ﻫﯿﺪرازﯾﻞ، تست آنتی اکسیدان، مهار رادیکال آزاد

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عنوان مقاله به انگلیسی: Enzyme assays

عنوان مقاله به فارسی: سنجش فعالیت های آنزیم

کلمات کلیدی مقاله: واحدهای آنزیم، راﺑﻄﻪ. ﻣﯿﮑﺎﺋﯿﻠﯿﺲ- ﻣﻨﺘﻮن، وابستگی به pH، وابستگی به گرما، واکنش های آنزیمی برگشت پذیر، سنجش آنزیم های جفت شده

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عنوان مقاله به انگلیسی: The pollution of the marine environment by plastic debris: a review

عنوان مقاله به فارسی: بررسی آلودگی محیط زیست دریایی با زباله های پلاستیکی

کلمات کلیدی مقاله: زباله های پلاستیکی، آلودگی، محیط زیست دریایی

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عنوان مقاله به انگلیسی: A survey of tools for the analysis of quantitative PCR (qPCR) data

عنوان مقاله به فارسی:  بررسی ابزارهای تحلیل کمی داده های PCR 

کلمات کلیدی مقاله:  qPCR،  تحلیل داده، MIQE، RDML، نرم افزار، ابزار

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عنوان مقاله به انگلیسی: Impacts of pollution on coastal and marine ecosystems including coastal and marine fisheries and approach for management: a review and synthesis

عنوان مقاله به فارسی: تاثیرآلودگی براکوسیستم ساحل و دریا از جمله آبزیان ساحلی و دریایی و ارائه ی رویکرد مدیریتی: تحلیل و بررسی

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 عنوان مقاله به انگلیسی: Infrared spectroscopy of proteins

عنوان مقاله به فارسی: طیف سنجی فروسرخ پروتئین ها

کلمات کلیدی مقاله: طیف سنجی مادون قرمز، FTIR، پروتئین، ساختار پروتئینی، آب، آمید I، زمجیره جانبی آمینواسید، فعالیت آنزیمی، تفاوت طیف سنجی

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عنوان مقاله به انگلیسی: Comparison of the ARMA, ARIMA, and the autoregressive artificial neural network models in forecasting the monthly inflow of Dez dam reservoir

عنوان مقاله به فارسی:  ARMA، ARIMA، و مدل های خودهمبسته شبکه عصبی مصنوعی در پیش بینی جریان درون ریز سد

 چکیده انگلیسی مقاله:

 The goal of the present research is forecasting the inflow of Dez dam reservoir by using Auto Regressive Moving Average (ARMA) and Auto Regressive Integrated Moving Average (ARIMA) models while increasing the number of parameters in order to increase the forecast accuracy to four parameters and comparing them with the static and dynamic artificial neural networks. In this research, monthly discharges from 1960 to 2007 were used. The statistics related to first 42 years were used to train the models and the 5 past years were used to forecast. In ARMA and ARIMA models, the polynomial was derived respectively with four and six parameters to forecast the inflow. In the artificial neural network, the radial and sigmoid activity functions were used with several different neurons in the hidden layers. By comparing root mean square error (RMSE) and mean bias error (MBE), dynamic artificial neural network model with sigmoid activity function and 17 neurons in the hidden layer was chosen as the best model for forecasting inflow of the Dez dam reservoir. Inflow of the dam reservoir in the 12 past months shows that ARIMA model had a less error compared with the ARMA model. Static and Dynamic autoregressive artificial neural networks with activity sigmoid function can forecast the inflow to the dam reservoirs from the past 60 months.

کلمات کلیدی: ARIMA، ARMA، شبکه عصبی مصنوعی خودهمبسته، سد Dez، پیش بینی جریان درون ریز سد

 

 

عنوان مقاله به انگلیسی: Hydrolysis of lignocellulosic materials for ethanol production: a review 

عنوان مقاله به فارسی: بررسی هیدرولیز مواد لیگنوسلولزی برای تولید اتانول 

 چکیده انگلیسی مقاله:

Lignocellulosic biomass can be utilized to produce ethanol, a promising alternative energy source for the limited crude oil. There are mainly two processes involved in the conversion: hydrolysis of cellulose in the lignocellulosic biomass to produce reducing sugars, and fermentation of the sugars to ethanol. The cost of ethanol production from lignocellulosic materials is relatively high based on current technologies, and the main challenges are the low yield and high cost of the hydrolysis process. Considerable research efforts have been made to improve the hydrolysis of lignocellulosic materials. Pretreatment of lignocellulosic materials to remove lignin and hemicellulose can significantly enhance the hydrolysis of cellulose. Optimization of the cellulase enzymes and the enzyme loading can also improve the hydrolysis. Simultaneous saccharification and fermentation effectively removes glucose, which is an inhibitor to cellulase activity, thus increasing the yield and rate of cellulose hydrolysis.

کلمات کلیدی: سلولز، سلولاز، اتانول، تخمیر، آب کافت (هیدرولیز)، زیست توده لینگوسلولزی، پیش تیمار

 

 

عنوان مقاله به انگلیسی: Fatal attraction: the intuitive appeal of GMO opposition

 عنوان مقاله به فارسی: جاذبه مهلک: مقابله با کشش غریزی ارگانیسم های تغییر ژن یافته

چکیده انگلیسی مقاله:  

Public opposition to genetically modified organisms (GMOs) remains strong. By contrast, studies demonstrate again and again that GM crops make a valuable contribution to the development of a sustainable type of agriculture. The discrepancy between public opinion and the scientific evidence requires an explanation. We argue that intuitive expectations about the world render the human mind vulnerable to particular misrepresentations of GMOs. We explain how the involvement of particular intuitions accounts for the popularity, persistence, and typical features of GM opposition and tackle possible objections to our approach. To conclude, we discuss the implications for science education, science communication, and the environmental movement.

کلمات کلیدی: ارگانیسم های تغییر ژن یافته، مقابله عمومی، ذهن ناخودآگاه، جاذبه های فرهنگی

 

 

عنوان مقاله به انگلیسی:  Generalized linear mixed models: a practical guide for ecology and evolution

عنوان فارسی مقاله: مدل های آمیخته خطی تعمیم یافته: راه کاری کاربردی در زیست شناسی و تکامل

چکیده انگلیسی مقاله: 

How should ecologists and evolutionary biologists analyze nonnormal data that involve random effects? Nonnormal data such as counts or proportions often defy classical statistical procedures. Generalized linear mixed models (GLMMs) provide a more flexible approach for analyzing nonnormal data when random effects are present. The explosion of research on GLMMs in the last decade has generated considerable uncertainty for practitioners in ecology and evolution. Despite the availability of accurate techniques for estimating GLMM parameters in simple cases, complex GLMMs are challenging to fit and statistical inference such as hypothesis testing remains difficult. We review the use (and misuse) of GLMMs in ecology and evolution, discuss estimation and inference and summarize ‘best-practice’ data analysis procedures for scientists facing this challenge.

 

 

عنوان مقاله به انگلیسی: Biodiesel production: a review

عنوان مقاله به فارسی: بررسی تولید سوخت دوست دار محیط زیست

چکیده انگلیسی مقاله:

Biodiesel has become more attractive recently because of its environmental benefits and the fact that it is made from renewable resources. The cost of biodiesel, however, is the main hurdle to commercialization of the product. The used cooking oils are used as raw material, adaption of continuous transesterification process and recovery of high quality glycerol from biodiesel by-product (glycerol) are primary options to be considered to lower the cost of biodiesel. There are four primary ways to make biodiesel, direct use and blending, microemulsions, thermal cracking (pyrolysis) and transesterification. The most commonly used method is transesterification of vegetable oils and animal fats. The transesterification reaction is affected by molar ratio of glycerides to alcohol, catalysts, reaction temperature, reaction time and free fatty acids and water content of oils or fats. The mechanism and kinetics of the transesterification show how the reaction occurs and progresses. The processes of transesterification and its downstream operations are also addressed.

کلمات کلیدی: زیست دیزل، تبادل استری، آمیختن، میکروامولسیون، شکست حرارتی

 

 

عنوان مقاله به انگلیسی: Biological effects of essential oils – A review

عنوان مقاله به فارسی: بررسی تاثیر بیولوژیکی عطرهای روغنی

چکیده انگلیسی مقاله: 

Since the middle ages, essential oils have been widely used for bactericidal, virucidal, fungicidal, antiparasitical, insecticidal, medicinal and cosmetic applications, especially nowadays in pharmaceutical, sanitary, cosmetic, agricultural and food industries. Because of the mode of extraction, mostly by distillation from aromatic plants, they contain a variety of volatile molecules such as terpenes and terpenoids, phenol-derived aromatic components and aliphatic components. In vitro physicochemical assays characterise most of them as antioxidants. However, recent work shows that in eukaryotic cells, essential oils can act as prooxidants affecting inner cell membranes and organelles such as mitochondria. Depending on type and concentration, they exhibit cytotoxic effects on living cells but are usually non-genotoxic. In some cases, changes in intracellular redox potential and mitochondrial dysfunction induced by essential oils can be associated with their capacity to exert antigenotoxic effects. These findings suggest that, at least in part, the encountered beneficial effects of essential oils are due to prooxidant effects on the cellular level.

کلمات کلیدی: اسانس های روغنی، مسمومیت سلولی، مسمومیت ژنی، مسمویت آنتی ژنی، فعالیت پرواکسیدان ها

 

 

عنوان انگلیسی مقاله : Essential oils: their antibacterial properties and potential applications in foods—a review

عنوان مقاله به فارسی: اسانس های روغنی: بررسی خواص آنتی باکتریایی و کاربردهای بالقوه آنها در موادغذایی

چکیده مقاله به انگلیسی:

In vitro studies have demonstrated antibacterial activity of essential oils (EOs) againstListeria monocytogenesSalmonella typhimuriumEscherichia coli O157:H7, Shigella dysenteriaBacillus cereus and Staphylococcus aureus at levels between 0.2 and 10 μl ml−1. Gram-negative organisms are slightly less susceptible than gram-positive bacteria. A number of EO components has been identified as effective antibacterials, e.g. carvacrol, thymol, eugenol, perillaldehyde, cinnamaldehyde and cinnamic acid, having minimum inhibitory concentrations (MICs) of 0.05–5 μl ml−1 in vitro. A higher concentration is needed to achieve the same effect in foods. Studies with fresh meat, meat products, fish, milk, dairy products, vegetables, fruit and cooked rice have shown that the concentration needed to achieve a significant antibacterial effect is around 0.5–20 μl g−1 in foods and about 0.1–10 μl ml−1 in solutions for washing fruit and vegetables. EOs comprise a large number of components and it is likely that their mode of action involves several targets in the bacterial cell. The hydrophobicity of EOs enables them to partition in the lipids of the cell membrane and mitochondria, rendering them permeable and leading to leakage of cell contents. Physical conditions that improve the action of EOs are low pH, low temperature and low oxygen levels. Synergism has been observed between carvacrol and its precursor p-cymene and between cinnamaldehyde and eugenol. Synergy between EO components and mild preservation methods has also been observed. Some EO components are legally registered flavourings in the EU and the USA. Undesirable organoleptic effects can be limited by careful selection of EOs according to the type of food.

کلمات کلیدی: اسانس های روغنی، آنتی باکتری یایی، نگهدارنده ها، پاتوژن های حامل مواد مغذی

 

 

عنوان مقاله به انگلیسی: Comparison of ABTS, DPPH, FRAP, and ORAC assays for estimating antioxidant activity from guava fruit extracts

عنوان مقاله به فارسی: مقایسه عیار ABTS، DPPH، و ORAC برای ارزیابی فعالیت آنتی اکسیدان های عصاره ی میوه گواوا

چکیده مقاله به انگلیسی: 

Guava fruit extracts were analyzed for antioxidant activity measured in methanol extract (AOAM), antioxidant activity measured in dichloromethane extract (AOAD), ascorbic acid, total phenolics, and total carotenoids contents. The ABTS, DPPH, and FRAP assays were used for determining both AOAM and AOAD, whereas the ORAC was used for determining only AOAM. Averaged AOAM [μM Trolox equivalent (TE)/g fresh mass (FM)] were 31.1, 25.2, 26.1, and 21.3 as determined by the ABTS, DPPH, FRAP, and ORAC assays, respectively. Averaged AOAD (μM TE/g FM) were 0.44, 0.27, and 0.16 as determined by the ABTS, DPPH, and FRAP assays, respectively. AOAM determined by all assays were well correlated with ascorbic acid (0.61⩽r⩽0.92) and total phenolics (0.81⩽r⩽0.97) and also among themselves (0.68⩽r⩽0.97) but had negative correlation with total carotenoids (−0.67⩽r⩽−0.81).

کلمات کلیدی: اسید اسکوربیک، فنولیک، کاروتنوئید، گلابی وحشی (Psidium guajava L.)

 

 

عنوان مقاله به انگلیسی: Antioxidants: Characterization, natural sources, extraction and analysis

عنوان مقاله به فارسی: آنتی اکسیدان ها: مشخصه یابی، منابع طبیعی، استخراج و تحلیل

چکیده مقاله به انگلیسی:

Recently many review papers regarding antioxidants from different sources and different extraction and quantification procedures have been published. However none of them has all the information regarding antioxidants (chemistry, sources, extraction and quantification). This article tries to take a different perspective on antioxidants for the new researcher involved in this field. Antioxidants from fruit, vegetables and beverages play an important role in human health, for example preventing cancer and cardiovascular diseases, and lowering the incidence of different diseases. In this paper the main classes of antioxidants are presented: vitamins, carotenoids and polyphenols. Recently, many analytical methodologies involving diverse instrumental techniques have been developed for the extraction, separation, identification and quantification of these compounds. Antioxidants have been quantified by different researchers using one or more of these methods: in vivo, in vitro, electrochemical, chemiluminescent, electron spin resonance, chromatography, capillary electrophoresis, nuclear magnetic resonance, near infrared spectroscopy and mass spectrometry methods.

کلمات کلیدی: آنتی اکسیدان، ساختارهای شیمیایی، فواید بهداشتی، استخراج، شناسایی، تعیین خواص

 

 

عنوان انگلیسی مقاله: Inhibition of anaerobic digestion process: A review

عنوان مقاله به فارسی: بررسی مهار روند هضم بی هوازی

چکیده مقاله به انگلیسی: 

Anaerobic digestion is an attractive waste treatment practice in which both pollution control and energy recovery can be achieved. Many agricultural and industrial wastes are ideal candidates for anaerobic digestion because they contain high levels of easily biodegradable materials. Problems such as low methane yield and process instability are often encountered in anaerobic digestion, preventing this technique from being widely applied. A wide variety of inhibitory substances are the primary cause of anaerobic digester upset or failure since they are present in substantial concentrations in wastes. Considerable research efforts have been made to identify the mechanism and the controlling factors of inhibition. This review provides a detailed summary of the research conducted on the inhibition of anaerobic processes. The inhibitors commonly present in anaerobic digesters include ammonia, sulfide, light metal ions, heavy metals, and organics. Due to the difference in anaerobic inocula, waste composition, and experimental methods and conditions, literature results on inhibition caused by specific toxicants vary widely. Co-digestion with other waste, adaptation of microorganisms to inhibitory substances, and incorporation of methods to remove or counteract toxicants before anaerobic digestion can significantly improve the waste treatment efficiency.

کلمات کلیدی: هضم بی هوازی، ضایعات کشاورزی، ضایعات صنعتی، ضایعات شهری

 

 

عنوان مقاله به انگلیسی:  The role of urban parks for the sustainable city

عنوان مقاله به فارسی: نقش پارک های شهری در پایدارسازی شهر

International efforts to preserve the natural environment are mainly concerned with large, bio-diverse and relatively untouched ecosystems or with individual animal or vegetal species, either endangered or threatened with extinction. Much less attention is being paid to that type of nature close to where people live and work, to small-scale green areas in cities and to their benefits to people. Increasing empirical evidence, however, indicates that the presence of natural areas contributes to the quality of life in many ways. Besides many environmental and ecological services, urban nature provides important social and psychological benefits to human societies, which enrich human life with meanings and emotions. The main concern of this paper is to address the importance of urban nature for citizens’ well being and for the sustainability of the city they inhabit. Some results of a survey conducted among visitors of an urban park in Amsterdam (The Netherlands) are presented and discussed. The issues investigated concern people’s motives for urban nature, the emotional dimension involved in the experience of nature and its importance for people’s general well being. Results confirm that the experience of nature in urban environment is source of positive feelings and beneficial services, which fulfill important immaterial and non-consumptive human needs. Implications for the sustainability of the city will be analyzed and discussed.

کلمات کلیدی: پارک های شهری، کیفیت زندگی، پایدارسازی شهر

 

 

عنوان انگلیسی مقاله:  Global pollinator declines: trends, impacts and drivers

عنوان فارسی مقاله: کاهش گرده افشانی جهانی: روند، اثرات و عوامل محرک

Pollinators are a key component of global biodiversity, providing vital ecosystem services to crops and wild plants. There is clear evidence of recent declines in both wild and domesticated pollinators, and parallel declines in the plants that rely upon them. Here we describe the nature and extent of reported declines, and review the potential drivers of pollinator loss, including habitat loss and fragmentation, agrochemicals, pathogens, alien species, climate change and the interactions between them. Pollinator declines can result in loss of pollination services which have important negative ecological and economic impacts that could significantly affect the maintenance of wild plant diversity, wider ecosystem stability, crop production, food security and human welfare.

 

 

عنوان انگلیسی مقاله: A typology for the classification, description and valuation of ecosystem functions, goods and services

عنوان فارسی مقاله: استفاده از علم گونه شناسی در طبقه بندی، تشریح و ارزیابی کارکردها، ویژگی ها و خدمات یک اکوسیستم

چکیده مقاله به انگلیسی:

An increasing amount of information is being collected on the ecological and socio-economic value of goods and services provided by natural and semi-natural ecosystems. However, much of this information appears scattered throughout a disciplinary academic literature, unpublished government agency reports, and across the World Wide Web. In addition, data on ecosystem goods and services often appears at incompatible scales of analysis and is classified differently by different authors. In order to make comparative ecological economic analysis possible, a standardized framework for the comprehensive assessment of ecosystem functions, goods and services is needed. In response to this challenge, this paper presents a conceptual framework and typology for describing, classifying and valuing ecosystem functions, goods and services in a clear and consistent manner. In the following analysis, a classification is given for the fullest possible range of 23 ecosystem functions that provide a much larger number of goods and services. In the second part of the paper, a checklist and matrix is provided, linking these ecosystem functions to the main ecological, socio–cultural and economic valuation methods.

کلمات کلیدی: طبقه بندی کارکردهای اکوسیستم، گونه شناسی ویژگی ها و خدمات، ارزیابی اکولوژیکی و اجتماعی اقتصادی

 

 

عنوان مقاله به انگلیسی: Pretreatment technologies for an efficient bioethanol production process based on enzymatic hydrolysis: A review

عنوان مقاله به فارسی: بررسی فناوری های مبتنی بر هیدرولیز آنزیمی پیش تیمار برای استفاده در فرآیند تولید کارآمد بیواتانول 

چکیده مقاله به انگلیسی:

Biofuel produced from lignocellulosic materials, so-called second generation bioethanol shows energetic, economic and environmental advantages in comparison to bioethanol from starch or sugar. However, physical and chemical barriers caused by the close association of the main components of lignocellulosic biomass, hinder the hydrolysis of cellulose and hemicellulose to fermentable sugars. The main goal of pretreatment is to increase the enzyme accessibility improving digestibility of cellulose. Each pretreatment has a specific effect on the cellulose, hemicellulose and lignin fraction thus, different pretreatment methods and conditions should be chosen according to the process configuration selected for the subsequent hydrolysis and fermentation steps. This paper reviews the most interesting technologies for ethanol production from lignocellulose and it points out several key properties that should be targeted for low-cost and advanced pretreatment processes.

کلمات کلیدی: پیش تیمار، بیواتانول، هیدرولیز آنزیمی

 

 

عنوان انگلیسی مقاله: Promoting ecosystem and human health in urban areas using Green Infrastructure: A literature review

عنوان مقاله به فارسی: ارتقا اکوسیستم و سلامت انسان در مناطق شهری با توسعه فضای سبز

چکیده انگلیسی مقاله: 

Europe is a highly urbanised continent. The consequent loss and degradation of urban and peri-urban green space could adversely affect ecosystems as well as human health and well-being. The aim of this paper is to formulate a conceptual framework of associations between urban green space, and ecosystem and human health. Through an interdisciplinary literature review the concepts of Green Infrastructure, ecosystem health, and human health and well-being are discussed. The possible contributions of urban and peri-urban green space systems, or Green Infrastructure, on both ecosystem and human health are critically reviewed. Finally, based on a synthesis of the literature a conceptual framework is presented. The proposed conceptual framework highlights many dynamic factors, and their complex interactions, affecting ecosystem health and human health in urban areas. This framework forms the context into which extant and new research can be placed. In this way it forms the basis for a new interdisciplinary research agenda.

کلمات کلیدی: سلامت عمومی، رفاه انسان، توسعه فضای سبز، اکوسیستم در مناطق شهری، سلامت اکوسیستم

 

 

عنوان مقاله به انگلیسی: Stakeholder participation for environmental management: A literature review

عنوان مقاله به فارسی: مشارکت ذینفعان در مدیریت محیط زیست: بررسی ادبیات تحقیق

چکیده مقاله به انگلیسی:

The complex and dynamic nature of environmental problems requires flexible and transparent decision-making that embraces a diversity of knowledges and values. For this reason, stakeholder participation in environmental decision-making has been increasingly sought and embedded into national and international policy. Although many benefits have been claimed for participation, disillusionment has grown amongst practitioners and stakeholders who have felt let down when these claims are not realised. This review first traces the development of participatory approaches in different disciplinary and geographical contexts, and reviews typologies that can be used to categorise and select participatory methods. It then reviews evidence for normative and pragmatic benefits of participation, and evaluates limitations and drawbacks. Although few of the claims that are made have been tested, there is evidence that stakeholder participation can enhance the quality of environmental decisions by considering more comprehensive information inputs. However, the quality of decisions made through stakeholder participation is strongly dependant on the nature of the process leading to them. Eight features of best practice participation are then identified from a Grounded Theory Analysis of the literature. These features emphasise the need to replace a “tool-kit” approach, which emphasises selecting the relevant tools for the job, with an approach that emphasises participation as a process. It is argued that stakeholder participation needs to be underpinned by a philosophy that emphasises empowerment, equity, trust and learning. Where relevant, participation should be considered as early as possible and throughout the process, representing relevant stakeholders systematically. The process needs to have clear objectives from the outset, and should not overlook the need for highly skilled facilitation. Local and scientific knowledges can be integrated to provide a more comprehensive understanding of complex and dynamic socio-ecological systems and processes. Such knowledge can also be used to evaluate the appropriateness of potential technical and local solutions to environmental problems. Finally, it is argued that to overcome many of its limitations, stakeholder participation must be institutionalised, creating organisational cultures that can facilitate processes where goals are negotiated and outcomes are necessarily uncertain. In this light, participatory processes may seem very risky, but there is growing evidence that if well designed, these perceived risks may be well worth taking. The review concludes by identifying future research needs.

کلمات کلیدی: مشارکت ذینفعان، مدیریت محیط زیست، دانش، تصمیم گیری، بهترین روش ها، گونه شناسی

 

 

عنوان مقاله به انگلیسی: Agricultural expansion and its impacts on tropical nature

عنوان مقاله به فارسی: توسعه کشاورزی و تاثیر آن بر طبیعت استوایی

The human population is projected to reach 11 billion this century, with the greatest increases in tropical developing nations. This growth, in concert with rising per-capita consumption, will require large increases in food and biofuel production. How will these megatrends affect tropical terrestrial and aquatic ecosystems and biodiversity? We foresee (i) major expansion and intensification of tropical agriculture, especially in Sub-Saharan Africa and South America; (ii) continuing rapid loss and alteration of tropical old-growth forests, woodlands, and semi-arid environments; (iii) a pivotal role for new roadways in determining the spatial extent of agriculture; and (iv) intensified conflicts between food production and nature conservation. Key priorities are to improve technologies and policies that promote more ecologically efficient food production while optimizing the allocation of lands to conservation and agriculture.

کلمات کلیدی: تقویت کشاورزی، تنوع زیستی، ذخیره کربن، قطع درختان جنگلی، صرفه جویی در زمین، انقراض گونه های زیستی

 

 

عنوان انگلیسی مقاله : Features of promising technologies for pretreatment of lignocellulosic biomass

عنوان فارسی مقاله: ویژگی فناوری های موثر در پیش تیمار زیست توده لینگوسلولزی

چکیده مقاله به انگلیسی: 

Cellulosic plant material represents an as-of-yet untapped source of fermentable sugars for significant industrial use. Many physio-chemical structural and compositional factors hinder the enzymatic digestibility of cellulose present in lignocellulosic biomass. The goal of any pretreatment technology is to alter or remove structural and compositional impediments to hydrolysis in order to improve the rate of enzyme hydrolysis and increase yields of fermentable sugars from cellulose or hemicellulose. These methods cause physical and/or chemical changes in the plant biomass in order to achieve this result. Experimental investigation of physical changes and chemical reactions that occur during pretreatment is required for the development of effective and mechanistic models that can be used for the rational design of pretreatment processes. Furthermore, pretreatment processing conditions must be tailored to the specific chemical and structural composition of the various, and variable, sources of lignocellulosic biomass. This paper reviews process parameters and their fundamental modes of action for promising pretreatment methods.

 

  

عنوان مقاله به انگلیسی:  Oxidative stress, antioxidants and stress tolerance

عنوان مقاله به فارسی: استرس اکسایشی، آنتی اکسیدان ها و تحمل استرس

چکیده مقاله به انگلیسی:

Traditionally, reactive oxygen intermediates (ROIs) were considered to be toxic by-products of aerobic metabolism, which were disposed of using antioxidants. However, in recent years, it has become apparent that plants actively produce ROIs as signaling molecules to control processes such as programmed cell death, abiotic stress responses, pathogen defense and systemic signaling. Recent advances includng microarray studies and the development of mutants with altered ROI-scavenging mechanisms provide new insights into how the steady-state level of ROIs are controlled in cells. In addition, key steps of the signal transduction pathway that senses ROIs in plants have been identified. These raise several intriguing questions about the relationships between ROI signaling, ROI stress and the production and scavenging of ROIs in the different cellular compartments.

کلمات کلیدی: تنش نازیو، آنتی اکسیدان، فعل و انفعلات پاتوژن های گیاهی، مرگ سلولی برنامه ریزی شده، واسط انفعالی اکسیژن، هدایت سیگنال