抑制中厚板轧制过程中板坯弯曲的对策

研究了济钢中厚板粗轧机轧制过程中板坯的弯曲现象，从理论上分析了板坯弯曲的生成机理与改进措施，现场应用后，杜绝了板坯弯曲时撞击机架辊与高压水软管现象，提高了这些备件的使用寿命，取得了较好的效果。     

Ballooning population.

Discusses W. R. Bartz (see record 1970-18782-001) and P. R. Ehrlich's (1968) considerations of overpopulation and its associated problems. The author sees the ballooning population here and on other continents as the world's most serious crisis, it directly ties into or heightens every human misery. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The population slide

The level of total fertility in Bangladesh has fallen from 7 in 1975 to 3 today, the sharpest fertility transition in South Asia. Fertility decline in Bangladesh and Nepal follows such transition occurring first in Sri Lanka, then in India. While in Western countries, levels of fertility began to fall once an advanced stage of development had been reached, these new declines in South Asia are not directly correlated with indicators of development such as increased literacy or the alleviation of poverty. Bangladesh has experienced major fertility decline despite being one of the world's 20 poorest countries. Fertility decline in Bangladesh may be attributed to a combination of an effective government family planning program, a general desire among Bangladesh's population to bear fewer children, reductions in mortality, the availability of microcredit, changes in women's status, and the provision of health and family planning information over the radio 6 hours per day.     

World population problem.

Comments on the advice of S. M. Zifferblatt and C. G. Hendricks (see record 1975-07273-001) to psychologists about the superiority of applied behavioral analysis of societal problems that uses overpopuation as a case in point. The scope and focus of their proposed solutions to the problem were not specified. The psychology of population dynamics and family planning should focus on the individual, the couple and family, the local community, the nation, and the world. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Non-linear age-dependent population growth

A non-linear problem arising from age-dependent population dynamics is studied. Existence and uniqueness and a priori bounds for the growth of population are proved. Moreover the existence and the stability of equilibrium age distributions is investigated.     

Change in sex ratio of a Drosophila population in relation to population size

Changes in sex ratio with population size fluctuations were studied in natural and cage populations of Drosophila. It was shown that the proportion of females decreased with an increase in population size both in natural and laboratory populations. If laboratory populations were maintained on a poor diet, this effect was absent. The amplitude of number fluctuation was shown to be higher in males than in females. The possible role of density-dependent selection on sex in the control of population size dynamics is discussed.     

Medicine, population and war

The colonization mechanisms of enteropathogenic Aeromonas strains are poorly characterized, but recent studies indicate that some filamentous structures are intestinal adhesins. This study describes the purification and characterization of a long, flexible pilus from a gastroenteritis-associated strain of Aeromonas veronii biovar sobria. SDS-PAGE analysis (various conditions) of pili preparations yielded a pilin protein band of approximately 21 kDa. Its N-terminal amino acid sequence was unambiguous and homologous with those of type IV pilins. Immunogold electron microscopy with rabbit antisera produced against this pilin protein (SFP) decorated single pili and rope-like bundles of pili on the bacterial surface. These were seen more frequently on strains grown at 22 degrees C compared with 37 degrees C and in liquid rather than on solid medium. SFP was not detected on any of 104 strains of Aeromonas (different species and sources) from our culture collection, although morphologically similar structures were seen on a number of these strains. This finding and differences among other published amino acid sequences show that Aeromonas type IV pili are antigenically diverse. Bundle-forming type IV 'class B' pili are important in the virulence of other enteropathogenic bacteria. The N-terminal amino acid sequence of the Aeromonas SFP, however, showed closer homology to the type IV 'class A' pilins. Studies are in progress to investigate the role of SFP in Aeromonas virulence.     

Molecular medicine and population control

As we uncover the physiological and molecular mechanisms behind human reproduction, we gain the potential to exert more control over our reproductive capabilities. In the past two decades, the prospects for 'infertile' women to bear children, or 'sterile' men to father them, have improved dramatically; recently, women have given birth in their sixties, well beyond their natural menopause. Thanks to developments in contraception, couples can now enjoy an active sex-life without a significant risk of pregnancy, and more accurately control the size and timing of their families. But these new freedoms have a price: they also have the potential to cause demographic distortions, medical harm to individuals and abuse of human rights.     

Castleman's lymphoma among Japanese population

Since our report on Castlemans lymphoma in 1958, a total of 53 cases by 36 authors have appeared in the Japanese literatures. Among them our first case, whose tumor was found in the pelvic cavity, would be the first patient ever reported in Japan. The outstanding histological features of Castleman's lymphoma consists of variegated morphology of germinal centers due to peculiar capillary proliferation, multicentric germinal centers in a lymph follicle showing a chimerical figure and expansive growth of lymph follicles by compressing interfollicular area. Among these Japanese population, we have noticed the highest age incidence between 10-19 years, with somewhat female predominance, the most preferential site in the upper part of the body, and, as compared to the other ethnical subjects, more frequent tumor multiplicity and less usual plasma cell type of the tumor. A possible pathogenesis that Castleman's lymphoma could be "a benign lymphoma" in contrast to malignant lymphomas is emphasized from various aspects.     

Handling covariates in population pharmacokinetics

Population models were developed to analyze processes, described by parametric models, from measurements obtained in a sample of individuals. In order to analyze the sources of interindividual variability, covariates may be incorporated in the population analysis. The exploratory analyses and the two-stage approaches which use standard non-linear regression techniques are simple tools to select meaningful covariates. The global population approaches may be divided into two classes within which the covariates are handled differently: the parametric and the non-parametric methods. The power as well as the limitations of each approach regarding handling of covariates are illustrated and compared using the same data set which concerns the pharmacokinetics of gentamicin in neonates. With parametric approaches a second-stage model between structural parameters and covariates has to be defined. In the non-parametric method the joint distribution of parameters and covariates is estimated without parametric assumptions; however, it is assumed that covariates are observed with some error and parameters involved in functional relationships are not estimated. The important results concerning gentamicin in neonates were found by the two methods.