The Energy Cost of the Excretion of Urine

The energy consumption of the kidney has been estimated by a number of experimenters and by different methods; and the values obtained are all of the same order of magnitude. The concordance of these values justifies an estimate of the efficiency of the kidney, i.e., of the ratio of the work performed, calculated from the constitution of the urine, to the energy used. The efficiency of the kidney, defined in this way, appears, even in health, to be about 1-2 per cent. So far as the authors are aware, there are no data inconsistent with this low figure. Rather the reverse, this association of the thermodynamic work with the observed energy consumption of the kidney permits the correlation of a large number of facts regarding the behavior of the kidney in health and disease

Oxidation of glucose by iodine in the presence of insulin

This investigation was undertaken with the purpose of determining whether insulin, alone or in the presence of certain animal fluids, has any influence upon glucose in vitro. The establishment of such an influence might have much significance in relation both to the study of carbohydrate metabolism and to the development of methods of assaying insulin

Cozymase. A study of purification methods

Cozymase is one of the essential components of the complex enzyme mixture which effects alcoholic fermentation in the absence of living cells. The separation of the mixture into zymase and cozymase was first accomplished by Harden and Young [1] by means of ultrafiltration through a gelatin-impregnated Chamberland filter candle. The residue and filtrate as thus prepared possessed, separately, no fermentative action, but when mixed were found to produce a rapid fermentation. The active constituent of the residue was named zymase, while that constituent of the filtrate responsible for the reactivation of the residue was named cozymase. We studied the purification produced in our material by a variety of reagents. In the investigation we have repeated much of the work done by von Euler and Myrbäk [2], and several differences have been found, which appear difficult to explain solely upon the basis of the lower initial purity of our material. As certain of the experiments show distinct promise, we hope to be able to extend the work upon a material of considerably higher original purity, such as was employed by von Euler and Myrbäk

Landholding. Rural Fertility and Internal Migration in Developing Countries: Econometric Evidence from Cross-National Data

We develop an empirical model of the interaction of rural fertility and rural urban migration which incorporates the effects of landholding patterns. Cross section data for 26 developing countries are used to test the model. The statistical results support the hypothesis of a positive relationship between fertility and out-migration in the rural sector and lend credence to some of the propositions regarding the impact of landholding patterns. A reduced form of the model is derived from the statistical results, and its policy implications are considered

Industrial Arts Objectives

Several incorrect concepts have caused the Industrial Arts work to fail to function to its fullest extent. One idea is that of regarding the school shop only as a producer of things; if students produce good things they are successful. The individual as a learner is hardly taken into consideration; the project on which he works and the skillfulness with which he manipulates tools and materials are only seen

A learning index for the Midget Wiggly Block Test for mechanical ability

The writer became interested in testing mechanical ability while taking a course in the 1957 summer session at the Iowa State Teachers College dealing with the problem of teaching industrial arts. The teacher of this course was Dr. Howard O. Reed who had devised the Midget Wiggly Block Test for Mechanical Ability, which will be referred to hereafter in this report as the Midget Wiggly Block Test. During a class presentation, Reed state that there may be a learning process involved in the repeated assembling of the Midget Wiggly Block Test and presented a single formula for computing a score which he termed learning index. He further indicated that this learning index had not been tested experimentally. The purpose of this study is to establish the relationship of this learning index to other measures of pupil performance

The determination of carbon dioxide in fermenting mixtures

In connection with a research on enzymic behavior it was necessary to develop a simple and expeditious method for the determination of the carbon dioxide formed during fermentations. The most suitable method of carbon dioxide analysis appeared to be the procedure evolved by Cain and Maxwell [1] for the determination of carbon in steel. They absorbed the carbon dioxide, formed by combustion, in known volumes of barium hydroxide solution and followed the precipitation of barium carbonate by measurements of the electrical conductivity of the solution. The idea has been applied by Spoehr and McGee [2,3] to the determination of carbon dioxide in their studies on plant respiration. This paper describes the development of this general method so as to render it applicable to studies on fermentation

Small group activities within academic communities improve the connectedness of students and faculty.

BackgroundThe University of California, San Diego, School of Medicine implemented a curriculum change that included reduction of lectures, incorporation of problem-based learning and other small group activities. Six academic communities were introduced for teaching longitudinal curricular content and organizing extracurricular activities.MethodsSurveys were collected from 904 first- and second-year medical students over 6 years. Student satisfaction data with their sense of connectedness and community support were collected before and after the implementation of the new curriculum. In a follow-up survey, medical students rated factors that contributed to their sense of connectedness with faculty and students (n = 134).ResultsStudents' perception of connectedness to faculty significantly increased following implementation of a curriculum change that included academic communities. Students ranked small group clinical skills activities within academic communities significantly higher than other activities concerning their sense of connectedness with faculty. Students' perception of connectedness among each other was high at baseline and did not significantly change. Small group activities scored higher than extracurricular activities regarding students' connectedness among themselves.ConclusionsThe implementation of a new curriculum with more small group educational activities including academic communities enhanced connectedness between students and faculty and resulted in an increased sense of community