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791.
A. S. M. Abdul Matin 《Policy Sciences》1987,20(1):99-103
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
792.
Robert A. Dahl 《Scandinavian political studies》1987,10(3):195-206
I want to sketch the general shape of several new structures that would in my view provide stronger support for democracy than is provided by any existing society. I call these sketches for a democratic Utopia not because I would expect these structures to inaugurate a perfect democracy, whatever that might be, nor because they are beyond human reach. On the contrary the institutions I want to suggest are well within human reach. I call them Utopian only because I am not able to point with confidence to the historical forces that are likely to bring them about.
The structures I have in mind are designed to strengthen freedom and equality among citizens of democratic orders. 相似文献
The structures I have in mind are designed to strengthen freedom and equality among citizens of democratic orders. 相似文献
793.
794.
795.
Rachel A. Vannatta 《Journal of youth and adolescence》1996,25(2):149-160
This study examined gender differences in self-reported suicidal behavior in relation to the risk factors of tobacco use, alcohol use, drug use, school misconduct, academic difficulties, home environment, sexual activity, and violence among seventh-through twelfth grade students (N=3461)in a northern Midwest school district. Data were gathered from the Survey Instrument of Attitude/Behavior administered in the school district during the spring of 1993. The dependent variables were suicidal activity and suicidal tendency. Stepwise forward regression ordered the independent factors in predicting suicidal activity and suicidal tendency for the male and female samples. The comparison of regression results revealed the following: (1) the independent factors accounted for more variance in male suicidal activity and tendency than in female suicidal activity and tendency; (2) as the level of suicidality increased, so did the frequency of violent behaviors among both genders; (3) leading predictors for suicidal activity were similar between gender; and (4) gender differences were displayed in predictors of suicidal tendency.Major interests include risk taking behaviors, youth suicide, and educator use of research. 相似文献
796.
797.
David A. Bositis 《Political Behavior》1988,10(4):333-348
This paper assesses the participant method as a research design strategy and offers some observations on the utility of such an approach to research. In particular, the method is examined for its utility in theory testing and for providing a more substantial understanding of roles in political behavior. A typology of roles germane to the participant observation process is presented. The use of participant observation in political science is examined, and finally, some illustrations of the participant method are presented and analyzed. 相似文献
798.
799.
Years of neglect, combined with the recent development of a “hands on” judicial policy have resulted in a jail crisis in America. States, recognizing their contribution to this situation, have begun to develop policies designed to assist local jail officials in operating safe, humane, and constitutional facilities. These state efforts are a form o f mandating, and primarily concern minimum operating standards and inspections programs. In this research we investigate three questions related to state mandating of local jail operations: (1) what is the extent of state involvement, (2) what factors are associated with state involvement, and (3) what is the impact of state involvement? Our findings indicate (1) states have been active in developing and administering jail mandates, (2) state involvement is associated with state-level corrections policy, and (3) jail standards and inspections programs have a substantial impact on local jail performance. We conclude with a discussion of how state and local governments may proceed in the process of developing standards, inspections, and enforcement procedures. 相似文献
800.
One of the recent trends in the field of criminal justice has been the development of state jail standards. The nature of local politics has meant that jails have been among the most poorly funded and operated governmental institutions. The result of decades of neglect is a fertile ground for inmate litigation. The interest shown by the courts, in a variety of operational and procedural areas, has been a key factor in leading many states to assume a greater role in local jail oversight. This article examines some of the problems facing jails and describes state efforts to address these problems through state-level jail standards and enforcement procedures. 相似文献