26 research outputs found
Measurement of pepsin in porcine gastric juice
The method for measurement of pepsin in human gastric juice as devised by Anson and modified by Berstad has been used for testing pepsin secretion from Heidenhain pouches in pigs. Twenty samples may be analysed at one time with accuracy. Variations in ambient temperature and humidity, and contamination of samples with bile, were found to interfere with the accuracy of the method. There was no change in activity after immediate freezing at -20°C or after storage at -20°C for up to 3 months. After repeated thawing and refreezing on 4 consecutive days, there was a fall in activity on the fourth day only.S. Afr. Med. J., 48, 1873 (1974)
Controlling for Prior Attainment Reduces the Positive Influence that Single-Gender Classroom Initiatives Exert on High School Students’ Scholastic Achievements.
Research points to the positive impact that gender-segregated schooling and classroom initiatives exert on academic attainment. An evaluation of these studies which reveal positive effects highlights, however, that students are typically selectively assigned to single- or mixed-gender instructional settings, presenting a methodological confound. The current study controls for students’ prior attainment to appraise the efficacy of a single-gender classroom initiative implemented in a co-educational high school in the United Kingdom. Secondary data analysis (using archived data) was performed on 266 middle-ability, 11–12 year-old students’ standardized test scores in Languages (English, foreign language), STEM-related (Mathematics, Science, Information and Communication Technology), and Non-STEM subjects (art, music, drama). Ninety-eight students (54, 55% female) were taught in single-gender and 168 (69, 41% female) in mixed-gender classrooms. Students undertook identical tests irrespective of classroom type, which were graded in accordance with U.K national curriculum guidelines. Controlling for students’ prior attainment, findings indicate that students do not appear to benefit from being taught in single-gender relative to mixed-gender classrooms in Language and STEM-related subjects. Young women benefitted from being taught in mixed-gender relative to single-gender classes for Non-STEM subjects. However, when prior ability is not controlled for, the intervention appears to be effective for all school subjects, highlighting the confounding influence of selective admissions. These findings suggest that gender-segregated classroom initiatives may not bolster students’ grades. It is argued that studies that do not control for selection effects may tell us little about the effectiveness of such interventions on scholastic achievement
A flexible unkinkable cannula and its obstruction by dicalcium orthophosphate concretions
Chronic cannulation of an abdominal viscus or pouch is aided by the use of a cannula which does not leak or kink. Existing cannulae have been modified to achieve this. An unusual complication was encountered in jejunal cannulae after 1 - 3 months; large concretions of dicalcium orthophosphate precipitated on the inner cannula flange, completely blocking the lumen. Concretions were derived from the food, precipitation being aided by physicochemical factors in the jejunum.S. Afr. Med. J., 48, 1879 (1974)
A framework for an alternatives assessment dashboard for evaluating chemical alternatives applied to flame retardants for electronic applications
Raising Teachers’ Voice on Achievement in Urban Schools in England: An Introduction
© 2014, Springer Science+Business Media New York. There are intense policy pressures on urban schools and teachers working with different cohorts of disadvantaged students to ‘raise achievement’ and ‘close the gap’ in England. Known in the academic literature as disadvantage schools, in government policy circles they were formerly labelled ‘challenging schools’ now ‘under-performing schools’ or ‘socially-deprived schools’. These urban schools are compelled to meet external policy expectations in regards accountability (national benchmarks and floor targets) or face sanctions. This editorial begins with this extant school policy on achievement and describes a school–university partnership initiative in a northern city that brings together teachers, school Heads and assistant Heads with academic partners, currently without system support, to address disadvantaged students’ lives, learning needs and schooling experiences. The article then canvasses what has been done over 3 years with this first cohort to engage in teacher research activity informing school improvement oriented to equity and social justice, and introduces their work now made public in this journal. The intention of this special edition is to showcase these teachers’ voice, honed by the practical–pedagogical work done against the odds to advocate more realistic policies and practices that are locally sensitive and contextually specific. It is an example of one local struggle