University of Minnesota

About: University of Minnesota is a education organization based out in Minneapolis, Minnesota, United States. It is known for research contribution in the topics: Population & Transplantation. The organization has 117432 authors who have published 257986 publications receiving 11944239 citations. The organization is also known as: University of Minnesota, Twin Cities & University of Minnesota-Twin Cities.

Estimating glomerular filtration rate from serum creatinine and cystatin C.

Abstract: A b s t r ac t Background Estimates of glomerular filtration rate (GFR) that are based on serum creatinine are routinely used; however, they are imprecise, potentially leading to the overdiagnosis of chronic kidney disease. Cystatin C is an alternative filtration marker for estimating GFR. Methods Using cross-sectional analyses, we developed estimating equations based on cystatin C alone and in combination with creatinine in diverse populations totaling 5352 participants from 13 studies. These equations were then validated in 1119 participants from 5 different studies in which GFR had been measured. Cystatin and creatinine assays were traceable to primary reference materials. Results Mean measured GFRs were 68 and 70 ml per minute per 1.73 m 2 of body-surface area in the development and validation data sets, respectively. In the validation data set, the creatinine–cystatin C equation performed better than equations that used creatinine or cystatin C alone. Bias was similar among the three equations, with a median difference between measured and estimated GFR of 3.9 ml per minute per 1.73 m 2 with the combined equation, as compared with 3.7 and 3.4 ml per minute per 1.73 m 2 with the creatinine equation and the cystatin C equation (P = 0.07 and P = 0.05), respectively. Precision was improved with the combined equation (interquartile range of the difference, 13.4 vs. 15.4 and 16.4 ml per minute per 1.73 m 2 , respectively [P = 0.001 and P 30% of measured GFR, 8.5 vs. 12.8 and 14.1, respectively [P<0.001 for both comparisons]). In participants whose estimated GFR based on creatinine was 45 to 74 ml per minute per 1.73 m 2 , the combined equation improved the classification of measured GFR as either less than 60 ml per minute per 1.73 m 2 or greater than or equal to 60 ml per minute per 1.73 m 2 (net reclassification index, 19.4% [P<0.001]) and correctly reclassified 16.9% of those with an estimated GFR of 45 to 59 ml per minute per 1.73 m 2 as having a GFR of 60 ml or higher per minute per 1.73 m 2 . Conclusions The combined creatinine–cystatin C equation performed better than equations based on either of these markers alone and may be useful as a confirmatory test for chronic kidney disease. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases.)

Graphene/Polymer Nanocomposites

Abstract: Graphene has emerged as a subject of enormous scientific interest due to its exceptional electron transport, mechanical properties, and high surface area. When incorporated appropriately, these atomically thin carbon sheets can significantly improve physical properties of host polymers at extremely small loading. We first review production routes to exfoliated graphite with an emphasis on top-down strategies starting from graphite oxide, including advantages and disadvantages of each method. Then solvent- and melt-based strategies to disperse chemically or thermally reduced graphene oxide in polymers are discussed. Analytical techniques for characterizing particle dimensions, surface characteristics, and dispersion in matrix polymers are also introduced. We summarize electrical, thermal, mechanical, and gas barrier properties of the graphene/polymer nanocomposites. We conclude this review listing current challenges associated with processing and scalability of graphene composites and future perspectives f...

Resilience and development: Contributions from the study of children who overcome adversity

Abstract: This article reviews the research on resilience in order to delineate its significance and potential for understanding normal development. Resilience refers to the process of, capacity for, or outcome of successful adaptation despite challenging or threatening circumstances. Three resilience phenomena are reviewed: (a) good outcomes in high-risk children, (b) sustained competence in children under stress, and (c) recovery from trauma. It is concluded that human psychological development is highly buffered and that long-lasting consequences of adversity usually are associated with either organic damage or severe interference in the normative protective processes embedded in the caregiving system. Children who experience chronic adversity fare better or recover more successfully when they have a positive relationship with a competent adult, they are good learners and problem-solvers, they are engaging to other people, and they have areas of competence and perceived efficacy valued by self or society. Future studies of resilience will need to focus on processes that facilitate adaptation. Such studies have the potential to illuminate the range and self-righting properties of, constraints on, and linkages among different aspects of cognitive, emotional, and social development.