Introducing evidence-based medicine into a community family medicine residency

In this article we discuss how we are introducing the concept of evidence-based medicine (EBM) into our Family Practice Residency Program. We review the basic concepts of EBM., show how these have been incorporated in the curriculum, and how they are applied to patient care. We identify the need for further work to evaluate our efforts and improve them.     

Effect of water and salt content on protein solubility and water retention of meat preblends

Different preblend water contents at a constant ionic strength were investigated to determine if increasing water availability would increase protein solubility and water retention in meat preblends. Four salt levels (0, 2, 4 and 8%) and four water levels (0, 20, 40 and 80% formulation water) were used with ground bovine semimembranosus muscle that had been frozen once. Ground muscle was mixed with either NaCl alone (0% formulation water) or NaCl and brine (20, 40 and 80% formulation water) for the 2, 4 and 8% NaCl treatments. Distilled water was used for the 0% NaCl treatment. The mixtures were stored at 5°C for 12 h. Following storage, the water/brine content was standardized, and protein solubility and water retention were measured. Elevating the water content of preblends, in which the salt concentration had been standardized, increased the water retained during centrifugation (P < 0·05). Although not statistically significant, a similar trend was observed for protein solubility. Four percent NaCl produced the greatest protein dissolution and water retention.     

Adaptive significance of the copulatory behavior pattern of male meadow voles (Microtus pennsylvanicus) in relation to induction of ovulation and implantation in females.

Investigated the adaptive significance of 2 attributes of the male vole copulatory behavior pattern, its elaborateness, and distinct temporal patterning in relation to the induction of ovulation and implantation in females. In Exp I (58 Ss) elaborateness of the male behavior pattern, as evidenced by extensive preejaculatory behavior and multiple ejaculatory series, was necessary for maximal ovulation and implantation in meadow vole females, especially older females. In Exp II, 16 male meadow voles were able to elicit ovulation and luteal activation in 51 females of 2 other Microtus species, even though the temporal patterning of male meadow vole behavior was completely different from the patterning of the females' conspecific males (20 Ss). Implantation did not occur apparently because of incomplete ova development. It is suggested that in Microtus a coadaptation exists between male behavior pattern and female stimulation requirements with respect to amount of stimulation but not to the specific temporal patterning of the stimulation. It is unlikely, therefore, that the different patterns of male copulatory behavior in Microtus would be effective in maintaining reproductive isolation among sympatric species. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Do grading standards affect student evaluations of teaching? Some new evidence on an old question.

The relationship between the grade a student receives and the evaluation the student gives to the instructor has been a topic of concern and extensive investigation in educational research. Ideally, teaching evaluations should be based on teaching effectiveness and not on leniency of grading standards. Previous studies using a variety of methodologies and statistical analyses have found inconclusive results. The present study, after factor analyzing teacher evaluations by 5,878 graduate and undergraduate students into 3 dimensions, found significant relationships between expected grade and the dimensions of Course Effectiveness, Teacher Effectiveness, and Course Difficulty. The 1st set of relationships is viewed as support for a nonbias interpretation of why grades and ratings correlate, whereas the latter 2 sets support a bias interpretation. Correlations between grades and evaluations varied across types of courses, with required courses showing the strongest correlations between grades and ratings. Since these courses are typically less popular than electives, grading leniency may have a greater influence on course evaluations. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effects of sea water and concentrated salt solutions on the fatigue of nylon 6,6 fibres

Cyclic fatigue and creep rupture tests have been run on high-tenacity nylon 6,6 single fibres, yarns and small ropes in air and sea water environments. Fatigue failure in each case is by a creep rupture mechanism; yarns and small ropes show the same fatigue sensitivity as do single fibres. Sea water reduces the strength by approximately 10% under most conditions. Concentrated metallic salt solutions which cause environmental stress cracking in bulk nylon do not degrade the fibres beyond the effect of plain water. Tests on oriented nylon specimens show that environmental stress crack sensitivity is greatly reduced by orientation.     

Modelling of the pressure swing air seperation process

A theoretical analysis is given of the separation of oxygen and nitrogen in air by a single column pressure swing gas separation process. The problem treated includes changes in mass flow due to adsorption. The findings are compared with data obtained using molecular sieve adsorbent.     

Properties of block versus random copolymers

Physical and mechanical properties of block copolymers are compared and correlated with the corresponding random copolymers. The important properties of melting point, transition temperatures, tensile strength, modulus, and elastic properties depend upon the structural arrangement of the molecular units comprising the polymer strecture. All available data suggest overwhelmingly that properties of block copolymers are superior to those of random copolymers. A block copolymer can have properties characteristic of each of the homopolymers from which it is derived as well as a set of properties due to the polymer strcture as a whole. Block copolymers have an advantage over random copolymers in that a crystalline polymer can be modified without significant reduction of its melting point, modulus, tensile strength, and elastic properties, and by suitable selection of a second component it affords a means of “building in” a particular property.     

Cyanoethylation of ketostearates

Reaction of methyl9(10)-ketostearate with acrylonitrile under basic catalysis leads to the formation of new carbon-carbon bonds by the introduction of one to four β-cyanoethyl groups on carbon atoms adjacent to the carbonyl function. Five cyanoethylated products of 4-heptanone have been isolated and identified. A GLC method has been developed to separate and determine four of the cyanoethylated derivatives of methyl 9(10)-keostearate and methyl 12-ketostearate but the fifth, the tetracyanoethylated product, cannot be determined by this procedure. With the aid of this analytical method a study of some of the reaction parameters was undertaken to determine the degree to which yields and product distribution could be influenced by change in reaction conditions. Among the factors studied were amount of catalyst, reagent ratio, reaction temperature, use of solvents and precision. These series of experiments revealed that the degree of cyanoethylation of methyl 9(10)-ketostearate can be varied within wide limits, but that monocyanoethylation cannot be accomplished in realistic yields without the simultaneous formation of polycyanoethylated products. Presented at the AOCS Meeting, New Orleans, April 1970. E. Mark. Nutr. Res. Div. ARS, USDA.