David W. Johnson

Bio: David W. Johnson is an academic researcher from University of Queensland. The author has contributed to research in topics: Peritoneal dialysis & Kidney disease. The author has an hindex of 160, co-authored 2714 publications receiving 140778 citations. Previous affiliations of David W. Johnson include Minnesota Department of Transportation & Open University.

Energizing Learning: The Instructional Power of Conflict:

Abstract: Although intellectual conflict may be an important instructional tool (because of its potential constructive outcomes), conflict is rarely structured in instructional situations (because of its potential destructive outcomes). Many educators may be apprehensive about instigating intellectual conflict among students because of the lack of operational procedures to guide them. Ideally, operational procedures should be based on social science theory that is validated by research. Constructive controversy is an instructional procedure that is designed to create intellectual conflict among students and that meets these criteria. The authors of this article summarize the theory underlying constructive controversy and review the results of their meta-analysis of the validating research. The positive outcomes indicate that intellectual conflict can have important and positive effects on student learning and well-being.

Synbiotics Easing Renal Failure by Improving Gut Microbiology (SYNERGY): A Randomized Trial

Abstract: Background and objectives The generation of key uremic nephrovascular toxins, indoxyl sulfate (IS), and p-cresyl sulfate (PCS), is attributed to the dysbiotic gut microbiota in CKD. The aim of our study was to evaluate whether synbiotic (pre- and probiotic) therapy alters the gut microbiota and reduces serum concentrations of microbiome–generated uremic toxins, IS and PCS, in patients with CKD. Design, setting, participants, & measurements Predialysis adult participants with CKD (eGFR=10–30 ml/min per 1.73 m2) were recruited between January 5, 2013 and November 12, 2013 to a randomized, double–blind, placebo–controlled, crossover trial of synbiotic therapy over 6 weeks (4-week washout). The primary outcome was serum IS. Secondary outcomes included serum PCS, stool microbiota profile, eGFR, proteinuria-albuminuria, urinary kidney injury molecule-1, serum inflammatory biomarkers (IL-1β, IL-6, IL-10, and TNF-α), serum oxidative stress biomarkers (F2-isoprostanes and glutathione peroxidase), serum LPS, patient-reported health, Gastrointestinal Symptom Score, and dietary intake. A prespecified subgroup analysis explored the effect of antibiotic use on treatment effect. Results Of 37 individuals randomized (age =69±10 years old; 57% men; eGFR=24±8 ml/min per 1.73 m2), 31 completed the study. Synbiotic therapy did not significantly reduce serum IS (−2 μmol/L; 95% confidence interval [95% CI], −5 to 1 μmol/L) but did significantly reduce serum PCS (−14 μmol/L; 95% CI, −27 to −2 μmol/L). Decreases in both PCS and IS concentrations were more pronounced in patients who did not receive antibiotics during the study (n=21; serum PCS, −25 μmol/L; 95% CI, −38 to −12 μmol/L; serum IS, −5 μmol/L; 95% CI, −8 to −1 μmol/L). Synbiotics also altered the stool microbiome, particularly with enrichment of Bifidobacterium and depletion of Ruminococcaceae. Except for an increase in albuminuria of 38 mg/24 h (P=0.03) in the synbiotic arm, no changes were observed in the other secondary outcomes. Conclusion In patients with CKD, synbiotics did not significantly reduce serum IS but did decrease serum PCS and favorably modified the stool microbiome. Large–scale clinical trials are justified.

Social Skills for Successful Group Work

Abstract: I n a 4th grade classroom the teacher is trying out learning groups \"This is a mess,\" she thinks. In one group, students are bickering over who is going to do the writing. In another group, one child sits quietly, too shy to participate Two members of a third group are talking about football while the third member works on the assignment \"My stu dents do not know how to work coop eratively,\" she sighs What is a teacher to do in such a situation? Simply placing students in groups and telling them to work to gether does not, in and of itself, pro duce cooperation and certainly not the higher achievement and positive social outcomes that can result from cooperative learning groups The rea son? Traditional group efforts may go wrong in many ways. Group members sometimes seek a free ride on others' work by \"leaving it to George\" to complete the group's tasks. Students who are stuck doing all the work sometimes decrease their efforts to avoid being suckers. High-ability group members may take over in ways that benefit themselves at the expense of lower achieving group members (the \"rich get richer\" effect). Pressures to conform may suppress individual Social skills—like other skills—must be teamed. But once learned, the abilities to cooperate and to work effectively with others will serve students well in school and later on in their careers

Social interdependence: interrelationships among theory, research, and practice.

Abstract: Social interdependence theory is a classic example of the interaction among theory, research, and practice. The premise of the theory is that the way in which goals are structured determines how individuals interact, which in turn creates outcomes. Over 750 research studies have been conducted in the past 11 decades on the relative merits of cooperative, competitive, and individualistic efforts and the conditions under which each is appropriate. These studies have validated, modified, refined, and extended the theory. Social interdependence theory has been widely applied, especially in education. The applications have resulted in revisions of the theory and the generation of considerable new research.

Assessment of Global Kidney Health Care Status

Abstract: Importance Kidney disease is a substantial worldwide clinical and public health problem, but information about available care is limited. Objective To collect information on the current state of readiness, capacity, and competence for the delivery of kidney care across countries and regions of the world. Design, Setting, and Participants Questionnaire survey administered from May to September 2016 by the International Society of Nephrology (ISN) to 130 ISN-affiliated countries with sampling of key stakeholders (national nephrology society leadership, policy makers, and patient organization representatives) identified by the country and regional nephrology leadership through the ISN. Main Outcomes and Measures Core areas of country capacity and response for kidney care. Results Responses were received from 125 of 130 countries (96%), including 289 of 337 individuals (85.8%, with a median of 2 respondents [interquartile range, 1-3]), representing an estimated 93% (6.8 billion) of the world’s population of 7.3 billion. There was wide variation in country readiness, capacity, and response in terms of service delivery, financing, workforce, information systems, and leadership and governance. Overall, 119 (95%), 95 (76%), and 94 (75%) countries had facilities for hemodialysis, peritoneal dialysis, and kidney transplantation, respectively. In contrast, 33 (94%), 16 (45%), and 12 (34%) countries in Africa had facilities for hemodialysis, peritoneal dialysis, and kidney transplantation, respectively. For chronic kidney disease (CKD) monitoring in primary care, serum creatinine with estimated glomerular filtration rate and proteinuria measurements were reported as always available in only 21 (18%) and 9 (8%) countries, respectively. Hemodialysis, peritoneal dialysis, and transplantation services were funded publicly and free at the point of care delivery in 50 (42%), 48 (51%), and 46 (49%) countries, respectively. The number of nephrologists was variable and was low ( Conclusions and Relevance This survey demonstrated significant interregional and intraregional variability in the current capacity for kidney care across the world, including important gaps in services and workforce. Assuming the responses accurately reflect the status of kidney care in the respondent countries, the findings may be useful to inform efforts to improve the quality of kidney care worldwide.

Initial sequencing and analysis of the human genome.

Abstract: The human genome holds an extraordinary trove of information about human development, physiology, medicine and evolution. Here we report the results of an international collaboration to produce and make freely available a draft sequence of the human genome. We also present an initial analysis of the data, describing some of the insights that can be gleaned from the sequence.

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

The social identity theory of intergroup behavior

Abstract: This chapter presents an outline of a theory of intergroup conflict and some preliminary data relating to the theory. Much of the work on the social psychology of intergroup relations has focused on patterns of individual prejudices and discrimination and on the motivational sequences of interpersonal interaction. The intensity of explicit intergroup conflicts of interests is closely related in human cultures to the degree of opprobrium attached to the notion of "renegade" or "traitor." The basic and highly reliable finding is that the trivial, ad hoc intergroup categorization leads to in-group favoritism and discrimination against the out-group. Many orthodox definitions of "social groups" are unduly restrictive when applied to the context of intergroup relations. The equation of social competition and intergroup conflict rests on the assumptions concerning an "ideal type" of social stratification in which the salient dimensions of intergroup differentiation are those involving scarce resources.