نتایج جستجو برای: and tomatoe planting requires extensive labor work

تعداد نتایج: 16896028  

Journal: :The journals of gerontology. Series B, Psychological sciences and social sciences 1997
J E Mutchler J A Burr A M Pienta M P Massagli

The purpose of this study is to examine alternative pathways to labor force exit among older men. Based on the life course perspective, we distinguish between crisp exits from the labor force, which are characterized as being unidirectional, and blurred transition patterns, which include repeated exists, entrances, and unemployment spells. Using longitudinal data from the 1984 Survey of Income ...

2007
Maurizio Mazzocco

The evaluation of policies designed to increase the early investment in children requires knowledge of the parents’ preferences for expenditure on children. In this paper it is shown that these preferences can be recovered using variables available in commonly used datasets. The method proposed in this paper improves upon the approach developed by Blundell, Chiappori, and Meghir (2005) in two w...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه تبریز - دانشکده شیمی 1392

in the present work, a simple and sensitive method was developed for determination of morphine and heroin using gold nanoparticles as resonance rayleigh scattering (rrs) and colorimetric technique’s probe. synthesized gold nanoparticles by sodium citrate reduction method have a negative charge layer on their surfaces because of self-assembled citrate anions on their surface. binding of morphin...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه شهید بهشتی - دانشکده علوم 1371

we describe here a suitable approach for the synthesis of n-unsubstituted monocyclic b-lactams under mild reaction conditions by the annelation of imines with substituted acetylchlorides. in this method the reaily available phtalimidoacetyl chloride were allowed to react with - dibenzylideneiminotoluene (hydrobenzamide) in the presence of an equimolar amount of triethylamine in refluxing toluen...

Journal: :health scope 0
ramazan mirzaei health promotion research center, [choomnowniwe~wi yzonemeniwomvws{m~{eof medical sciences, ir iran +98-9122887587, [email protected]; health promotion research center, [choomnowniwe~wi yzonemeniwomvws{m~{eof medical sciences, ir iran +98-9122887587, [email protected] hossein ansari health promotion research center, [choomnowniwe~wi yzonemeniwomvws{m~{eof medical sciences, ir iran +98-9122887587, [email protected] alireza ansari-moghaddam health promotion research center, [choomnowniwe~wi

background accident is an event that occurs suddenly, unexpectedly and inadvertently under unforeseen circumstances. accidents can have individual, social and economical effects 2080 injury cases including labor-law workers were studied in mashhad city, islamic republic of iran. their data were collected from the labor office archive. objectives this study was conducted to determine the effecti...

2005
James P. Ziliak

The wage elasticities of labor supply at the participation and hours worked margins are focal parameters of interest for understanding the work disincentive effects of taxes and transfers and the attendant design of optimal tax and transfer schemes. In this paper I use sweeping changes in U.S. tax policy, welfare policy, and the demand for skill over the 1980s and 1990s to identify the wage ela...

2016
Emmanuel DONKOR Enoch OWUSU-SEKYERE Victor OWUSU Henry JORDAAN

This paper employed the endogenous switching regression and propensity score matching methods to analyse the impact of row-planting technology on rice productivity using 470 rice farms in Northern Ghana. The empirical findings showed that the adoption of row-planting technology exerted greater positive impact on rice yields of smallholder farmers. In addition, rice yields of adopters and non-ad...

ژورنال: علوم آب و خاک 2000
خواجه ‌پور, محمدرضا , سیدی, فرامرز ,

Obtaining high seed and oil yields of sunflower requires coincidence of vegetative and reproductive stages of growth of the plant with suitable environmental conditions via selecting appropriate planting date. Since the suitable date of planting for sunflower cultivars under Isfahan environmental conditions was not determined, this experiment was conducted in 1996 at the Agricultural Research S...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید