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31.
Intra‐household constraints on educational attainment in rural households in Papua New Guinea 下载免费PDF全文
Sean Ryan Gina Koczberski George Nicolas Curry Emmanuel Germis 《Asia Pacific viewpoint》2017,58(1):27-40
This paper examines intra‐household and socio‐cultural factors leading to differential outcomes in educational attainment by gender and birth order amongst smallholder oil palm households in Papua New Guinea. Not all children share equitably in the household resources allocated to education: females have lower average education levels than males, and high birth order children have higher education attainment than lower birth order siblings, indicating preferential parental investment in sons and early born children. The findings demonstrate that despite households having regular access to relatively high incomes from oil palm and residing in close proximity to schools, primary school net enrolment rates remain significantly lower than those for East Asia and the Pacific region, and the millennium development goal of universal primary education has not been met. This finding is likely to be the result of a combination of intra‐household factors including gender power imbalances, low parental education levels, the agency of youth in educational decision‐making and the weakening attraction of education as a means of improving income‐earning potential. 相似文献
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33.
Autotrophic picoplankton dominate primary production over large oceanic regions but are believed to contribute relatively little to carbon export from surface layers. Using analyses of data from the equatorial Pacific Ocean and Arabian Sea, we show that the relative direct and indirect contribution of picoplankton to export is proportional to their total net primary production, despite their small size. We suggest that all primary producers, not just the large cells, can contribute to export from the surface layer of the ocean at rates proportional to their production rates. 相似文献
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35.
OBJECTIVES: To describe the US public health nutrition workforce and its future social, biological and fiscal challenges. DESIGN: Literature review primarily for the four workforce surveys conducted since 1985 by the Association of State and Territorial Public Health Nutrition Directors. SETTING: The United States. SUBJECTS: Nutrition personnel working in governmental health agencies. The 1985 and 1987 subjects were personnel in full-time budgeted positions employed in governmental health agencies providing predominantly population-based services. In 1994 and 1999 subjects were both full-time and part-time, employed in or funded by governmental health agencies, and provided both direct-care and population-based services. RESULTS: The workforce primarily focuses on direct-care services for pregnant and breast-feeding women, infants and children. The US Department of Agriculture funds 81.7 % of full-time equivalent positions, primarily through the WIC Program (Special Supplemental Nutrition Program for Women, Infants, and Children). Of those personnel working in WIC, 45 % have at least 10 years of experience compared to over 65 % of the non-WIC workforce. Continuing education needs of the WIC and non-WIC workforces differ. The workforce is increasingly more racially/ethnically diverse and with 18.2 % speaking Spanish as a second language. CONCLUSIONS: The future workforce will need to focus on increasing its diversity and cultural competence, and likely will need to address retirement within leadership positions. Little is known about the workforce's capacity to address the needs of the elderly, emergency preparedness and behavioural interventions. Fiscal challenges will require evidence-based practice demonstrating both costs and impact. Little is known about the broader public health nutrition workforce beyond governmental health agencies. 相似文献
36.
Yvonne Sadovy George Mitcheson Maria B. Rasotto 《Aquarium Sciences and Conservation》2001,3(4):253-263
The mandarinfish, Synchiropus splendidus, is a small, pelagic-spawning enthic dragonet of the western Pacific. Although popular in the marine aquarium trade, little
is known of its fishery or biology. All aquarium-trade animals are currently taken from the wild and the impact of heavy collecting
is unknown. The specialized and selective nature of the fishery for mandarinfish is described and its potential to disrupt
the mating system identified. As a possible alternative to wild capture and as an aid to sustainable exploitation, egg production
and early development relevant to mariculture are described, including egg output, embryo, larva and post-settlement development
to 30 days, based on live material. Egg output was determined for 40 females and ranged from 12 to 205 eggs. Embryo and larva
development were rapid, with settlement occurring within 14 days at 24–26 °C, and at 3.5 mm TL. The swimbladder is retained
in adults. Our limited attempts at raising the mandarinfish to settlement were encouraging and suggest an excellent potential
for mariculture with implications for both conservation and improved maintenance of fish in captivity. At present, given that
this species is difficult to maintain in captivity, it is only suitable for experienced aquarists. Preliminary diet information
is provided.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
37.
Transmission of resistance to common scab from the diploid to the tetraploid level via 4x-2x crosses in potatoes 总被引:1,自引:0,他引:1
Summary Diploid potato clones selected for their reaction to common scab and their ability to produce 2n male gametes were used in a series of crosses to a susceptible tetraploid female parent (cv. Shepody). In addition, two tetraploid clones were also selected for their reaction to common scab and crossed with Shepody as a female parent. Results indicated that resistance to common scab can be effectively transmitted from the diploid to the tetraploid level via 4x-2x crosses. Diploid parents producing 2n pollen via either first division or second division restitution can be used to transmit scab resistance. A relatively small proportion of resistant individuals could be recovered from susceptible x susceptible crosses in both 4x-2x and 4x-4x combinations. The data support a previously developed hypothesis that scab resistance is relatively simply inherited. 相似文献
38.
Panagiotis Michopoulos Kostas Kaoukis George Karetsos Theodoros Grigoratos Constantini Samara 《林业研究》2020,31(1):291-301
The fluxes of masses and the nutrients Ca,Mg,K,N,P and S were determined in the litterfall of two adjacent forest ecosystems of Hungarian oak(Quercus frainetto L.)and European beech(Fagus sylvatica L.)in a mountainous area of northeastern Greece in 2010–2015.The foliar litterfall for both species reached about 70%of the total litterfall,and was significantly higher from the other two fractions(woody and rest litterfall).The fluxes of masses and nutrients were compared between ecosystems for each fraction separately.Only one significant statistical difference was found,that of K in the woody litterfall.In addition,the stocks of masses and nutrients were calculated in the forest floors and mineral soils of the two ecosystems.Likewise,the stocks of nutrients in the forest floors and mineral soils were compared between ecosystems.In the L horizon of the forest floors,statistical differences,as a result of species effect,were found for the stocks of Ca and N.In the FH horizons,the masses and all the nutrient stocks differed significantly,as the beech plot had much higher quantities of organic matter and nutrients.These higher quantities were probably due to low soil temperatures(microclimate)and high acidity in the beech plot(species effect)that slowed down decomposition.In the mineral soils,the propagation of random error derived from random errors of the individual soil layers was an important factor in the statistical comparisons.Because of the soil acidity in the beech plot,the stocks of exchangeable base cations were significantly higher in the oak plot,whereas the other nutrient stocks did not differ. 相似文献
39.
The present study examines the pattern of accumulation of cadmium (Cd) and its biochemical effects on selected tissues of
a variety of African catfish (Clarias gariepinus), after exposure to various doses of Cd. The results obtained indicate that at the end of 21 days of exposure, the total
tissue organ cadmium concentration followed the pattern kidney > gill > liver > muscle for each of the exposure concentrations.
The levels of Cd in these organs were higher than those in ambient water. Moreover, while the rate of uptake of Cd increased
with time in the kidney, liver and muscle, it decreased in the gill. Superoxide dismutase (SOD) was significantly elevated
only in the kidney of catfish treated with 0.2 and 0.4 ppm of Cd for 7 days compared with the control. Conversely, gill SOD
was significantly decreased in the same concentrations of Cd-treated catfish relative to the control. Statistically similar
levels of SOD were observed in the liver, brain and muscle with all the treatments after the same duration of treatment. In
the fish exposed for 21 days, SOD activity was significantly decreased in the kidney with a corresponding increase in lipid
peroxidation (LPO), but it manifested only with the 0.2- and 0.4-ppm Cd treatment relative to the control. In the liver, however,
Cd exposure significantly increased SOD in the 0.2- and 0.4-ppm treatments of the same duration. In conclusion, the present
study indicates that the accumulation of Cd and its effect on SOD and LPO in C. gariepinus is dependent on concentration, tissue and time 相似文献
40.
Doychin Terziyski George Grozev Roumen Kalchev Angelina Stoeva 《Aquaculture International》2007,15(3-4):181-190
The effect of cattle organic fertilizer on plankton primary production and related variables was tested in six Bulgarian fish
ponds situated close to the town of Plovdiv in Bulgaria. At the beginning of the experiment (16th of May 2004, about 10 days
after filling with water) a suppression of plankton metabolism was observed and after that the ponds treated with manure demonstrated
significantly higher productivity than the controls, especially during the transition to the autumn season when the water
column was more regularly mixed. The other measured variables (Secchi disk readings, plankton chlorophyll-a and respiration, assimilation number per unit chlorophyll-a) did not show significant differences between the treated and control ponds. 相似文献