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991.
In an attempt to delay hatching without affecting their viability, the eggs ofLatheticus oryzae W. were subjected to cold treatment at 5° for varying periods and at different stages of their development. A small dose of 0.5 krad of gamma radiation was also given at each of those temperature treatments. Most of the eggs hatched at 30° following low-temperature exposures of 1 and 2 days. There was a significant decrease in hatch as the exposure period increased further (P<0.05). An egg exposure to 5° also led to an increase in egg period and the increase was nearly equal to the period of cold exposure. Radiation did not alter the situation.
Zusammenfassung Kühllagerung ist eine der gebr?uchlichsten Methoden für die Aufbewahrung von Insekteneiern. Um die optimalen Bedingungen für eine Vorratshaltung zu bestimmen, wurden 0–1 d alte Eier vonL. oryzae Temperaturen von 5° w?hrend 1–7 d ausgesetzt, nachdem sie verschieden lange bei 30° gehalten waren. Eine kleine Dosis von 0.5 krad Gammabestrahlung wurde bei jeder Temperaturbehandlung ebenfalls gegeben. Alle Eiproben wurden nach den verschiedenen K?ltebehandlungen in 30° zurückgebracht und die Wirkung auf Schlüpfprozentsatz und Eidauer bestimmt. Die Eidauer nahm zu, wenn die Eier bei 5° gehalten wurden, was anzeigt, da? die Embryogenese bei 5° unterdrückt wurde. Die Lebensf?higkeit der Eier wurde nicht beeintr?chtigt bei einer 5°-Einwirkungsdauer von 2 d, nahm aber bei weiterer Verl?ngerung der Expositionsdauer ab. Nur etwa 37% der Eier schlüpften (44,1% der Kontrolleier) nach 7-t?giger K?ltebehandlung. Bestrahlung beeinflu?te weder das Schlüpfen noch die Entwicklungsdauer.
  相似文献   
992.
In 1982, disabled workers who came on the social security disability insurance rolls from mid-1980 to mid-1981 had median monthly incomes of less than $500 if they were unmarried and less than $1,300 if they were married. These median monthly income levels, which include the income of a spouse and minor children if present, are roughly half those of the noninstitutionalized population aged 25-64. Social security benefits are the most important source of income for disabled workers and their families: They account for 40 percent of the total family income of married disabled workers and 65 percent of the total income of unmarried disabled workers. Social security benefits provide at least half of all income for more than 80 percent of unmarried disabled-worker beneficiaries and for 50 percent of the married beneficiaries. For married disabled-worker beneficiaries, earnings of the spouse are the second most important income source. Spousal earnings account for 28 percent of total income. Pensions and asset income each account for about 10 percent of total income for these married beneficiaries. Earnings are not an important source of income for unmarried disabled-worker beneficiaries for whom they amount to only about 3 percent of total income. Pensions, asset income, and public transfers each account for about 10 percent of total income of the unmarried beneficiaries.  相似文献   
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A distribution of income between rulers and subjects can be derived as an equilibrium of violence, rather than from considerations of marginal products of owned factors of production. Society is organized in ranks, and the occupants of each rank are provided with incomes just sufficient that obedience is preferable to rebellion. To incorporate such considerations into a model, it is necessary to recognize phenomena that are normally excluded from economic analysis: combat, the mortality rate (from natural causes and from violence) as a component of the utility function, and a rudimentary technology of control.  相似文献   
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998.
In 1983 the Government of Kenya embarked on an accelerated programme of decentralization known as ‘District Focus’. This exercise in devolution is aimed at promoting more effective and efficient use of scarce domestic resources through efforts to strengthen planning capacity at the district level, improve horizontal integration among operating ministry field agents, and expand authority to district heads of operating ministries for managing financial and procurement aspects of local project implementation. Given the importance of this initiative to the economic growth of Kenya and the current search for administrative reforms that could help accelerate rural development in Africa, District Focus merits close attention by development experts. This article reviews the historical background, content, and implementation progress of District Focus.  相似文献   
999.
Singapore is an island state with no formal lower tier of government. The network of consultation and mobilization created after Independence in 1959 is now raising important issues of consensus and compliance. Twenty-five years of continuous one-party rule offer opportunities to evaluate the working of the mechanisms of integration and participation. In the late 1980s the highly urbanized, multi-ethnic society is placing new demands on the government, and questions of decentralization and feedback are high on the political agenda.  相似文献   
1000.
Science policy analysts have traditionally classified R&D laboratories as government, private, or university. The authors argue that this view is outmoded and provides little help in understanding the rapidly changing environment of R&D laboratories. They provide and test an alternative scheme designed to cope with “sector blurring” and the intermingling of market and political influences on R&D laboratories. The authors also discuss implications of their scheme for a variety of contemporary science policy issues.  相似文献   
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