Management of Acute Glomerulonephritis

Glomerulonephritis is responsible for over one half of all cases of end-stage chronic renal failure and, in its most fulminant form, is a cause of acute, irreversible renal failure. Electron microscopy and immunofluorescent studies together with newly recognized clinical associations have revealed a wide variety of histologic subgroups and myriad etiologies for what was once regarded as a single, simple entity. The addition of electron microscopy has lent an entirely new dimension to the delineation of glomerulonephritis subtypes and offers a more reasonable approach to the search for treatment of these subtypes. It is, after all, not unreasonable to suppose that different etiologic factors and host responses are involved in the various pathologic lesions so clearly defined on electron microscopy. Immunofluorescent studies identify the presence of immune globulins and complement components in glomerular lesions and aid in recognition of their localization sites: they may reveal the contribution of fibrin deposition or specific antigens in the pathogenesis of glomerular involvement

Evaluation of a metal fuselage frame selectively reinforced with filamentary composites for space shuttle application

The development of metal structures reinforced with filamentary composites as a weight saving feature of the space shuttle components is discussed. A frame was selected for study that was representative of the type of construction used in the bulk frames of the orbiter vehicle. Theoretical and experimental investigations were conducted. Component tests were performed to evaluate the critical details used in the designs and to provide credibility to the weight saving results. A model frame was constructed of the reinforced metal material to provide a final evaluation of the construction under realistic load conditions

Carbon accretion in unthinned and thinned young-growth forest stands of the Alaskan perhumid coastal temperate rainforest.

BACKGROUND: Accounting for carbon gains and losses in young-growth forests is a key part of carbon assessments. A common silvicultural practice in young forests is thinning to increase the growth rate of residual trees. However, the effect of thinning on total stand carbon stock in these stands is uncertain. In this study we used data from 284 long-term growth and yield plots to quantify the carbon stock in unthinned and thinned young growth conifer stands in the Alaskan coastal temperate rainforest. We estimated carbon stocks and carbon accretion rates for three thinning treatments (basal area removal of 47, 60, and 73 %) and a no-thin treatment across a range of productivity classes and ages. We also accounted for the carbon content in dead trees to quantify the influence of both thinning and natural mortality in unthinned stands. RESULTS: The total tree carbon stock in naturally-regenerating unthinned young-growth forests estimated as the asymptote of the accretion curve was 484 (±26) Mg C ha-1 for live and dead trees and 398 (±20) Mg C ha-1 for live trees only. The total tree carbon stock was reduced by 16, 26, and 39 % at stand age 40 y across the increasing range of basal area removal. Modeled linear carbon accretion rates of stands 40 years after treatment were not markedly different with increasing intensity of basal area removal from reference stand values of 4.45 Mg C ha-1 year-1to treatment stand values of 5.01, 4.83, and 4.68 Mg C ha-1 year-1 respectively. However, the carbon stock reduction in thinned stands compared to the stock of carbon in the unthinned plots was maintained over the entire 100 year period of observation. CONCLUSIONS: Thinning treatments in regenerating forest stands reduce forest carbon stocks, while carbon accretion rates recovered and were similar to unthinned stands. However, that the reduction of carbon stocks in thinned stands persisted for a century indicate that the unthinned treatment option is the optimal choice for short-term carbon sequestration. Other ecologically beneficial results of thinning may override the loss of carbon due to treatment. Our model estimates can be used to calculate regional carbon losses, alleviating uncertainty in calculating the carbon cost of the treatments

Introduction

The 31st Stoneburner Lecture Series was planned to present an overview of some important aspects of clinical nephrology that we hope are of interest to a wide audience. The faculty for this symposium was drawn largely from the Medical College of Virginia Nephrology Division, and we were fortunate to have Dr. George E. Schreiner, Professor of Medicine at Georgetown University and a long-time friend, as our Stoneburner Lecturer

Annual Performance Reviews Of, For and By Faculty: A Qualitative Analysis of One Department's Experiences

Purpose: Although annual performance reviews and feedback are recommended for faculty development, best practices and faculty perceptions have not been documented. The authors sought to evaluate the process in one medical school department that established and has sustained an innovative review tradition for 25 years. Method: Content analysis of faculty reports and immersion/crystallization to analyze interviews. Results: Faculty reports described satisfaction and dissatisfaction; facilitators and barriers to goals; and requests for feedback, with community, collaboration and mentorship integral to all three. Interviewees emphasized practical challenges, the role of the mentor and the power of the review to establish community norms. Conclusion: Respondents generally found reviews constructive and supportive. The process informs departmental expectations and culture

Cancer and the Kidney

Cancer of the kidney is associated with a bewildering array of extrarenal symptoms, and conversely, tumors far removed from the kidney produce intriguing renal functional abnormalities. A variety of extrarenal complications are seen with hypernephromas, most of which rarely accompany Wilms tumors which grow rapidly and generally occur before the age of 7. Wilms tumors are quite susceptible to radiation therapy and surgery, and are to be strongly suspected when hypertension and an abdominal mass are found in a small child. Unless treated, they rapidly cause death and usually leave little opportunity for the patient to develop the striking extrarenal manifestations seen with hypernephroma

A Systematic Review of Research on Augmentative and Alternative Communication Brain-Computer Interface Systems for Individuals with Disabilities.

Augmentative and alternative communication brain-computer interface (AAC-BCI) systems are intended to offer communication access to people with severe speech and physical impairment (SSPI) without requiring volitional movement. As the field moves toward clinical implementation of AAC-BCI systems, research involving participants with SSPI is essential. Research has demonstrated variability in AAC-BCI system performance across users, and mixed results for comparisons of performance for users with and without disabilities. The aims of this systematic review were to (1) describe study, system, and participant characteristics reported in BCI research, (2) summarize the communication task performance of participants with disabilities using AAC-BCI systems, and (3) explore any differences in performance for participants with and without disabilities. Electronic databases were searched in May, 2018, and March, 2021, identifying 6065 records, of which 73 met inclusion criteria. Non-experimental study designs were common and sample sizes were typically small, with approximately half of studies involving five or fewer participants with disabilities. There was considerable variability in participant characteristics, and in how those characteristics were reported. Over 60% of studies reported an average selection accuracy ≤70% for participants with disabilities in at least one tested condition. However, some studies excluded participants who did not reach a specific system performance criterion, and others did not state whether any participants were excluded based on performance. Twenty-nine studies included participants both with and without disabilities, but few reported statistical analyses comparing performance between the two groups. Results suggest that AAC-BCI systems show promise for supporting communication for people with SSPI, but they remain ineffective for some individuals. The lack of standards in reporting outcome measures makes it difficult to synthesize data across studies. Further research is needed to demonstrate efficacy of AAC-BCI systems for people who experience SSPI of varying etiologies and severity levels, and these individuals should be included in system design and testing. Consensus in terminology and consistent participant, protocol, and performance description will facilitate the exploration of user and system characteristics that positively or negatively affect AAC-BCI use, and support innovations that will make this technology more useful to a broader group of people