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.

Training elementary school students to manage conflict.

Abstract: The effectiveness of a peer mediation program in a midwestern, suburban school in the United States was examined. Six classes (one combination second/third grade, one third grade, two fourth grades, and two fifth grades) containing 144 students received 9 hr of training in negotiating integrative agreements to their conflicts and mediating their classmates' conflicts. Eighty-three untrained third-, fourth-, and fifth-graders served as a control group. A peer mediation program was implemented. The role of mediator was rotated equally among all class members. A pretest/posttest, experimental/control group design was used. The results indicate that students successfully learned the negotiation and mediation procedures, were able to apply the procedures in actual conflict situations, and maintained this knowledge throughout the academic year.

Climate‐induced changes in the suitable habitat of cold‐water corals and commercially important deep‐sea fishes in the North Atlantic

Abstract: The deep sea plays a critical role in global climate regulation through uptake and storage of heat and carbon dioxide. However, this regulating service causes warming, acidification and deoxygenation of deep waters, leading to decreased food availability at the seafloor. These changes and their projections are likely to affect productivity, biodiversity and distributions of deep-sea fauna, thereby compromising key ecosystem services. Understanding how climate change can lead to shifts in deep-sea species distributions is critically important in developing management measures. We used environmental niche modelling along with the best available species occurrence data and environmental parameters to model habitat suitability for key cold-water coral and commercially important deep-sea fish species under present-day (1951-2000) environmental conditions and to project changes under severe, high emissions future (2081-2100) climate projections (RCP8.5 scenario) for the North Atlantic Ocean. Our models projected a decrease of 28%-100% in suitable habitat for cold-water corals and a shift in suitable habitat for deep-sea fishes of 2.0°-9.9° towards higher latitudes. The largest reductions in suitable habitat were projected for the scleractinian coral Lophelia pertusa and the octocoral Paragorgia arborea, with declines of at least 79% and 99% respectively. We projected the expansion of suitable habitat by 2100 only for the fishes Helicolenus dactylopterus and Sebastes mentella (20%-30%), mostly through northern latitudinal range expansion. Our results projected limited climate refugia locations in the North Atlantic by 2100 for scleractinian corals (30%-42% of present-day suitable habitat), even smaller refugia locations for the octocorals Acanella arbuscula and Acanthogorgia armata (6%-14%), and almost no refugia for P. arborea. Our results emphasize the need to understand how anticipated climate change will affect the distribution of deep-sea species including commercially important fishes and foundation species, and highlight the importance of identifying and preserving climate refugia for a range of area-based planning and management tools.

Staphylococcus aureus peritonitis in australian peritoneal dialysis patients: predictors, treatment, and outcomes in 503 cases

Abstract: Staphylococcus aureus peritonitis is a serious complication of peritoneal dialysis (PD). Since reports of the course and treatment of S. aureus peritonitis have generally been limited to small, single-center studies, the aim of the current investigation was to examine the frequency, predictors, treatment, and clinical outcomes of this condition in all 4675 patients receiving PD in Australia between 1 October 2003 and 31 December 2006. 3594 episodes of peritonitis occurred in 1984 patients and 503 (14%) episodes of S. aureus peritonitis occurred in 355 (8%) individuals. 273 (77%) patients experienced 1 episode of S. aureus peritonitis, 52 (15%) experienced 2 episodes, 19 (5%) experienced 3 episodes, and 11 (3%) experienced 4 or more episodes. The predominant antibiotics used as initial empiric therapy were vancomycin (61%) and cephazolin (31%). Once S. aureus was isolated and identified, the prescription of vancomycin did not appreciably change for methicillin-sensitive S. aureus (MSSA) peritonitis (59%) and increased for methicillin-resistant S. aureus (MRSA) peritonitis (84%). S. aureus peritonitis was associated with a higher rate of relapse than non-S. aureus peritonitis (20% vs 13%, p < 0.001) but comparable rates of hospitalization (67% vs 70%, p = 0.2), catheter removal (23% vs 21%, p = 0.4), hemodialysis transfer (18% vs 18%, p = 0.6), and death (2.2% vs 2.3%, p = 0.9). MRSA peritonitis was independently predictive of an increased risk of permanent hemodialysis transfer [odds ratio (OR) 2.11, 95% confidence interval (CI) 1.17 - 3.82] and tended to be associated with an increased risk of hospitalization (OR 2.00, 95% CI 0.96 - 4.19). The initial empiric antibiotic choice between vancomycin and cephazolin was not significantly associated with clinical outcomes, but serious adverse outcomes were more likely if vancomycin was not used for subsequent treatment of MRSA peritonitis. In conclusion, S. aureus peritonitis is a serious complication of PD, involves a small proportion of patients, and is associated with a high rate of relapse and repeat episodes. Other adverse clinical outcomes are similar to those for peritonitis overall but are significantly worse for MRSA peritonitis. Empiric initial therapy with either vancomycin or cephazolin results in comparable outcomes, provided vancomycin is prescribed when MRSA is isolated and identified.

A strategy for the conservation of biodiversity on mid-ocean ridges from deep-sea mining

Abstract: Mineral exploitation has spread from land to shallow coastal waters and is now planned for the offshore, deep seabed. Large seafloor areas are being approved for exploration for seafloor mineral deposits, creating an urgent need for regional environmental management plans. Networks of areas where mining and mining impacts are prohibited are key elements of these plans. We adapt marine reserve design principles to the distinctive biophysical environment of mid-ocean ridges, offer a framework for design and evaluation of these networks to support conservation of benthic ecosystems on mid-ocean ridges, and introduce projected climate-induced changes in the deep sea to the evaluation of reserve design. We enumerate a suite of metrics to measure network performance against conservation targets and network design criteria promulgated by the Convention on Biological Diversity. We apply these metrics to network scenarios on the northern and equatorial Mid-Atlantic Ridge, where contractors are exploring for seafloor massive sulfide (SMS) deposits. A latitudinally distributed network of areas performs well at (i) capturing ecologically important areas and 30 to 50% of the spreading ridge areas, (ii) replicating representative areas, (iii) maintaining along-ridge population connectivity, and (iv) protecting areas potentially less affected by climate-related changes. Critically, the network design is adaptive, allowing for refinement based on new knowledge and the location of mining sites, provided that design principles and conservation targets are maintained. This framework can be applied along the global mid-ocean ridge system as a precautionary measure to protect biodiversity and ecosystem function from impacts of SMS mining.

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.