نتایج جستجو برای: showed positive productivity changes

تعداد نتایج: 2314565  

2010
Peter Ebanyat Nico de Ridder Andre de Jager Robert J. Delve Mateete A. Bekunda Ken E. Giller

Smallholder farming systems in sub-Saharan Africa have undergone changes in land use, productivity and sustainability. Understanding of the drivers that have led to changes in land use in these systems and factors that influence the systems' sustainability is useful to guide appropriate targeting of intervention strategies for improvement. We studied low input Teso farming systems in eastern Ug...

2010
Matt McGue Steven Bacon

Seventy-nine monozygotic and 48 same-sex dizygotic twin pairs completed the Multidimensional Personality Questionnaire twice, averaging 20 years of age at first and 30 years at second testing. There were significant mean decreases in measures of Negative Emotionality (NE), increases in measures of Constraint (CO), but no significant mean changes for measures of Positive Emotionality (PE). Varia...

2013
Emily B. Peters Kirk R. Wythers Shuxia Zhang John B. Bradford Peter B. Reich

Large changes in atmospheric CO2, temperature, and precipitation are predicted by 2100, yet the long-term consequences for carbon (C), water, and nitrogen (N) cycling in forests are poorly understood. We applied the PnET-CN ecosystem model to compare the long-term effects of changing climate and atmospheric CO2 on productivity, evapotranspiration, runoff, and net nitrogen mineralization in curr...

Journal: :اقتصاد و توسعه کشاورزی 0
مقدسی مقدسی شرافتمند شرافتمند باغستانی باغستانی

abstract comparison of food prices in different periods, indicates fluctuations and continually upward trend. any change in agricultural sector variables, as main food supplier, will affect food price. productivity shocks and production gap are examples of such variables. in this paper ,hodrick prescott and kalman filters are used as generators of productivity shocks and production gap series. ...

Journal: :Journal of microbiology and biotechnology 2013
Yuntao Liu Jun Sun Zeyu Luo Shengqi Rao Yujie Su Yanjun Yang

This is the first report on using Catathelasma ventricosum for production of fruiting body and lignocellulosic enzymes. To improve the laccase activity and productivity of mushroom, the substrate was added with different supplements (eight aromatic compounds, Mn2+, and Cu2+). Based on the results, all these supplements can improve the laccase activity and productivity of C. ventricosum, and it ...

F. Hosseinzadeh Lotfi F. Rezai Balf, M. Alizadeh Afrouzi

One of the most popular approaches to measuring productivity changes is based on using Malmquist productivity indexes. In this paper we propose a method for obtaining interval Malmquist productivity index (IMPI). The classical DEA models have been before used for measuring the Malmquist productivity index. The current article extends DEA models for measuring the interval Malmquist productivity ...

2017
Abd El-Fatah Abomohra Wenbiao Jin Renjie Tu Song-Fang Han

Despite the promising research findings on microalgae as a feedstock for biodiesel, reduction of its production cost is still a challenge. One possible solution to overcome this problem is outdoor biomass production using wastewater as a growth medium. The present study aimed to evaluate the climate key parameters for Scenedesmus obliquus outdoor biomass production during different seasons, as ...

Elham Mojtahedin, Fatemeh Hadavi, Razyeh Lak,

The objective of this study is to understand the calcareous nannoplankton response to past environmental changes in the Strait of Hormuz during the Holocene. Calcareous nannoplankton is well abundant in the living phytoplankton community and a key component of the marine sediments. Due to its distinct reaction to environment changes and its good preservation potential, it is well suited for p...

2014
Mauricio Vergara Silvana Becerra Julio Berrios Nelson Osses Juan Reyes María Rodríguez-Moyá Ramon Gonzalez Claudia Altamirano

Mild hypothermia condition in mammalian cell culture technology has been one of the main focuses of research for the development of breeding strategies to maximize productivity of these production systems. Despite the large number of studies that show positive effects of mild hypothermia on specific productivity of r-proteins, no experimental approach has addressed the indirect effect of lower ...

G. Tohidi S. Tohidnia

This study examines the productivity changes of decision making units in situation whereinput price vectors are varying between them and inputs are heterogeneous; that is a noncompetitivemarket. We present a directional measure of cost Malmquist productivity indexwhere incorporates the decision maker's preference over productivity change over time. Asimple numerical example is designed to illus...

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