Mercury distribution across 14 U.S. Forests. Part I: spatial patterns of concentrations in biomass, litter, and soils.

Results from a systematic investigation of mercury (Hg) concentrations across 14 forest sites in the United States show highest concentrations in litter layers, strongly enriched in Hg compared to aboveground tissues and indicative of substantial postdepositional sorption of Hg. Soil Hg concentrations were lower than in litter, with highest concentrations in surface soils. Aboveground tissues showed no detectable spatial patterns, likely due to 17 different tree species present across sites. Litter and soil Hg concentrations positively correlated with carbon (C), latitude, precipitation, and clay (in soil), which together explained up to 94% of concentration variability. We observed strong latitudinal increases in Hg in soils and litter, in contrast to inverse latitudinal gradients of atmospheric deposition measures. Soil and litter Hg concentrations were closely linked to C contents, consistent with well-known associations between organic matter and Hg, and we propose that C also shapes distribution of Hg in forests at continental scales. The consistent link between C and Hg distribution may reflect a long-term legacy whereby old, C-rich soil and litter layers sequester atmospheric Hg depositions over long time periods. Based on a multiregression model, we present a distribution map of Hg concentrations in surface soils of the United States.

The DNA sequence and comparative analysis of human chromosome 10.

The finished sequence of human chromosome 10 comprises a total of 131,666,441 base pairs. It represents 99.4% of the euchromatic DNA and includes one megabase of heterochromatic sequence within the pericentromeric region of the short and long arm of the chromosome. Sequence annotation revealed 1,357 genes, of which 816 are protein coding, and 430 are pseudogenes. We observed widespread occurrence of overlapping coding genes (either strand) and identified 67 antisense transcripts. Our analysis suggests that both inter- and intrachromosomal segmental duplications have impacted on the gene count on chromosome 10. Multispecies comparative analysis indicated that we can readily annotate the protein-coding genes with current resources. We estimate that over 95% of all coding exons were identified in this study. Assessment of single base changes between the human chromosome 10 and chimpanzee sequence revealed nonsense mutations in only 21 coding genes with respect to the human sequence.

Centennial-scale reductions in nitrogen availability in temperate forests of the United States.

Forests cover 30% of the terrestrial Earth surface and are a major component of the global carbon (C) cycle. Humans have doubled the amount of global reactive nitrogen (N), increasing deposition of N onto forests worldwide. However, other global changes-especially climate change and elevated atmospheric carbon dioxide concentrations-are increasing demand for N, the element limiting primary productivity in temperate forests, which could be reducing N availability. To determine the long-term, integrated effects of global changes on forest N cycling, we measured stable N isotopes in wood, a proxy for N supply relative to demand, on large spatial and temporal scales across the continental U.S.A. Here, we show that forest N availability has generally declined across much of the U.S. since at least 1850 C.E. with cool, wet forests demonstrating the greatest declines. Across sites, recent trajectories of N availability were independent of recent atmospheric N deposition rates, implying a minor role for modern N deposition on the trajectory of N status of North American forests. Our results demonstrate that current trends of global changes are likely to be consistent with forest oligotrophication into the foreseeable future, further constraining forest C fixation and potentially storage.

Production of recombinant MART-1 proteins and specific antiMART-1 polyclonal and monoclonal antibodies: use in the characterization of the human melanoma antigen MART-1.

Recombinant human MART-1 protein was produced by bacterial and baculoviral-insect cell expression systems. By immunization with bacterial MBP-MART-1 fusion protein or MBP cleaved MART-1 protein, a rabbit polyclonal and two murine monoclonal antibodies specific for MART-1 were produced. These antibodies specifically detected MART-1 in immuno-precipitation, Western blotting, flow cytometric assays and in immunohistochemical analysis of tissue sections. They also stained cytoplasmic components in melanocytes and most melanoma cells in frozen or paraffin embedded tissue sections, indicating that these antibodies may be useful for the diagnosis of melanoma. One of the monoclonal antibodies M2-7 C10 recognized only human MART-1, but the other monoclonal antibody M2-9 E3 recognized both human and murine MART-1. The size of the human MART-1 molecule detected by SDS-PAGE with these antibodies was approximately 18 kDa, suggesting possible posttranslational modifications in the MART-1 protein. Subcellular fractionation studies suggested that MART-1 was present in melanosomes and endoplasmic reticulum, although known melanogenic enzymatic activities were not detected in the MART-1 protein. These reagents may be useful for biological studies on melanocytes and melanoma cells as well as for the development and monitoring of immunotherapy for patients with melanoma.

Developing strategic plans for academic general internal medicine.

There is an increasing need to train more primary care physicians. Therefore, it would be advantageous for academic general internal medicine (GIM) to develop strategies to meet these demands. Our GIM division developed a strategic planning process with the participant groups being the division faculty, a pertinent literature review (the surrogate expert), and selected medical administrators. The IDEALS systems design provided the conceptual framework for the strategic planning process. This process used the Delphi technique to develop the theoretically ideal work system based on the division's vision for its future role, and the Nominal Group Process Technique to create the recommended work system, using the Delphi results. The strategic planning process was economical and division faculty agreed that it was useful.

Genetic variation among geographic isolates of Rift Valley fever virus.

The genetic variation of Rift Valley fever virus (RVFV) was estimated by sequencing a portion of the M segment RNA of 22 isolates from a variety of host species collected over 34 years in 6 African countries. The M segment RNA of the Egyptian isolate, ZH501, which has been molecularly cloned and sequenced, was used as a reference for these comparisons. Specific gene regions, responsible for antigenic determinants presumed to play a role in protection against disease, were emphasized in these investigations. Comparative sequence data revealed that most isolates were very similar to ZH501 at both the nucleic acid and deduced amino acid sequence levels. Nucleic acid sequence variation range was 0-4.5%. Amino acid sequence variation range was 0-2.4%. We identified specific amino acid coding changes which may be involved in virus neutralization and may contribute to the virulence characteristics of RVFV.

Organizing patient safety research to identify risks and hazards.

Patient safety has become an international priority with major research programmes being carried out in the USA, UK, and elsewhere. The challenge is how to organize research efforts that will produce the greatest yield in making health care safer for patients. Patient safety research initiatives can be considered in three different stages: (1) identification of the risks and hazards; (2) design, implementation, and evaluation of patient safety practices; and (3) maintaining vigilance to ensure that a safe environment continues and patient safety cultures remain in place. Clearly, different research methods and approaches are needed at each of the different stages of the continuum. A number of research approaches can be used at stage 1 to identify risks and hazards including the use of medical records and administrative record review, event reporting, direct observation, process mapping, focus groups, probabilistic risk assessment, and safety culture assessment. No single method can be universally applied to identify risks and hazards in patient safety. Rather, multiple approaches using combinations of these methods should be used to increase identification of risks and hazards of health care associated injury or harm to patients.

Using standardised patients in an objective structured clinical examination as a patient safety tool.

Standardised patients (SPs) are a powerful form of simulation that has now become commonplace in training and assessment in medical education throughout the world. Standardised patients are individuals, with or without actual disease, who have been trained to portray a medical case in a consistent manner. They are now the gold standard for measuring the competence of physicians and other health professionals, and the quality of their practice. A common way in which SPs are used in performance assessment has been as part of an objective structured clinical examination (OSCE). The use of an SP based OSCE can be a powerful tool in measuring continued competence in human reliability and skill performance where such skills are a critical attribute to maintaining patient safety. This article will describe how an OSCE could be used as a patient safety tool based on cases derived from actual events related to postdonation information in the blood collection process. The OSCE was developed as a competency examination for health history takers. Postdonation information events in the blood collection process account for the majority of errors reported to the US Food and Drug Administration. SP based assessment is an important patient safety tool that could be applied to a variety of patient safety settings and situations, and should be considered an important weapon in the war on medical error and patient harm.

A system of analyzing medical errors to improve GME curricula and programs.

The report of the Institute of Medicine (IOM) To Err is Human recommended that both mandatory and voluntary event-reporting systems be established to identify and learn from errors. Because of the tight coupling of graduate medical education (GME) programs and the delivery of care, any event-reporting system used in a teaching hospital should be able to document the types of errors that are being made by graduate medical trainees (GTs). The authors performed an analysis of the root causes of events involving GTs that were recorded in hospital-based near-miss reporting systems. The root causes were classified using the Eindhoven Classification Model, medical version. Case histories of three separate events, one from an accident and emergency department in the United Kingdom, and two from a large teaching hospital in the United States, are used to illustrate the method. In all three cases, lack of knowledge on the part of the trainee contributed to the incident. Inadequate educational preparation had the potential for causing significant harm to the patient. Organizational causes were also present in each case, which illustrates the need to examine not only educational issues but also procedural and management issues related to GME. In each case, the analysis revealed in striking clarity deficiencies of educational content and problems of program structure. The authors conclude that doing a root-cause analysis in conjunction with a near-miss event-reporting system in a teaching hospital can be a valuable source of documented information to guide needed educational and system changes to GME programs.

Analyzing and adjusting for variables in a large-scale standardized-patient examination.

BACKGROUND: Structuring a clinical performance examination that uses standardized patients (SPs) for large groups of examinees often involves the use of two or more parallel forms of the examination with different SPs portraying the same case on the different forms. In addition, each form may be administered more than once on different days and/or in different locations. METHOD: To determine the effects of critical variables, such as day of examination, time of day (AM/PM), which of two simultaneous forms were taken, and sequencing effects, a univariate nested factorial analysis of variance was conducted for each of four annual SP examinations (1990-1993) at the University of Texas Southwestern Medical School. The examinations were given to approximately 200 second-year students per year at the end of their Introduction to Clinical Medicine course, and were graded on a pass/fail basis. RESULTS: Statistically significant differences were found for the following variables: (1) time of day (AM or PM) and day were significant but were inconsistent and of small magnitude; (2) sequencing for the first two stations was significant in each form of the examination and in all four years; and (3) form-within-case differences (i.e., differences between SPs) were significant between the two forms of the examination in each year of administration. To minimize the impacts of these variables, two mean equating formulas were applied to the scores. Few examinees' pass/fail status would have been affected by either adjustment. CONCLUSION: The parallel-forms examination format is minimally affected by the variables evaluated and is a fair pass/fail assessment of a student's performance. Mean equating is a valuable tool in minimizing the possibly unfair impact of variables on pass/fail decisions for homogeneous student populations.

Measuring and predicting academic generalists' work satisfaction: implications for retaining faculty.

PURPOSE: To develop a measure that could be used to identify interventions to improve the work satisfaction of academic generalists. METHODS: To field-test the measure, the authors surveyed the generalist faculty at the University of Texas Southwestern Medical Center at Dallas. Ninety-four (80%) of the faculty responded. The measure's reliability was established using Cronbach's alpha, and its validity was established with the Pearson correlation coefficient using a previously validated global work-satisfaction measure. Using ten work-satisfaction dimensions and selected faculty characteristics, the authors performed univariate and stepwise multiple regression analyses to predict the generalist faculty's global work satisfaction and intentions of leaving their positions. RESULTS: Work-satisfaction dimension predictors were autonomy in the workplace, professional status, teaching activities, clinical resources and activities, professional relationships, institutional governance, compensation, and professional advancement. Faculty characteristic predictors were gender, age, race or ethnicity, and living with children. CONCLUSION: The measure includes eight valid and reliable work-satisfaction dimensions that predict global work satisfaction or intentions to leave. Others may want to use this measure, along with the four faculty-characteristic predictors, as a management tool for improving academic generalists' work satisfaction and, ultimately, their performances and retention.

Encephalitis, lymphoid tissue depletion and secondary diseases associated with bovine immunodeficiency virus in a dairy herd.

Encephalitis, lymphoid tissue depletion and secondary infections occurred over a 5-yr-period in Holstein cows infected with bovine immunodeficiency virus (BIV). There were 59 cattle studied, the majority during 1991, when a severe environmental stress occurred, each with one or more primary causes of death, natural or by euthanasia, and most with several secondary diseases. The encephalitis was characterized by meningeal, perivascular and parenchymal infiltration with lymphocytes, occasional plasma cells and macrophages with perivascular edema in some cows. Affected areas included the cerebrum, cerebellum, and spinal cord with no particular distribution pattern recognized. The lymphoid depletion was primarily an absence of follicular development in nodes draining regions with secondary infections such as chronic mastitis and chronic suppurative pododermatitis. Paucity of lymphocytes in thymic-dependent regions of lymph nodes and the spleen suggested a primary depletion of T cells. Secondary infections were often multiple with each cow having several minor conditions, usually considered short-term and treatable. These included mastitis and pododermatitis, with many cows having non-responding abscesses, cellulitis and myositis attributed to injection site infections. A large number of the cattle had parturition difficulties such as dystocia, obturator paralysis, and metritis. Pulmonary, cardiovascular, and intestinal disease were recognized as both primary and secondary disease conditions. There was a high level of infection with bovine leukemia virus with 4 of the 59 cattle having lymphosarcoma. Under practical conditions, the infection with BIV has a different effect on the host than has been observed under experimental conditions. The presence of BIV combined with the stresses associated with parturition and a modern dairy production system were considered causal for the development of untreatable secondary diseases in immunocompromised cattle. The peak incidence in 1991 was attributed to increased environmental stress during renovation of the barn facility. During this time the cattle were kept on open pasture, exposed to an extremely wet winter, and spring weather conditions. The effect of co-infection with bovine leukemia virus, the influence of immunocompromise on the chronicity of mastitis, the relationship with laminitis and pododermatitis, and several questions related to viral transmission, complementarism with bovine leukemia virus, viral reactivation and immunoprophylaxis all remain as viable avenues for future investigations.

The attributes of medical event-reporting systems: experience with a prototype medical event-reporting system for transfusion medicine.

OBJECTIVE: To design, develop, and implement a prototype medical event-reporting system for use in transfusion medicine to improve transfusion safety by studying incidents and errors. METHODS: The IDEALS concept of design was used to identify specifications for the event-reporting system, and a Delphi and subsequent nominal group technique meetings were used to reach consensus on the development of the system. An interdisciplinary panel of experts from aviation safety, nuclear power, cognitive psychology, artificial intelligence, and education and representatives of major transfusion medicine organizations participated in the development process. Setting.- Three blood centers and three hospital transfusion services implemented the reporting system. RESULTS: A working prototype event-reporting system was recommended and implemented. The system has seven components: detection, selection, description, classification, computation, interpretation, and local evaluation. Its unique features include no-fault reporting initiated by the individual discovering the event, who submits a report that is investigated by local quality assurance personnel and forwarded to a nonregulatory central system for computation and interpretation. CONCLUSIONS: An event-reporting system incorporated into present quality assurance and risk management efforts can help organizations address system structural and procedural weakness where the potential for errors can adversely affect health care outcomes. Input from the end users of the system as well as from external experts should enable this reporting system to serve as a useful model for others who may develop event-reporting systems in other medical domains.

Natural and experimental bovine immunodeficiency virus infection in cattle.

Since 1989, the LSU dairy herd, with its high seroprevalence of BIV, was recognized to have a high incidence of common diseases that reduced the economic viability of the dairy. The herd had a high percentage of cows with encephalitis associated with depression and stupor, alteration of the immune system associated with secondary bacterial infections, and chronic inflammatory lesions of the feet and legs. The occurrence of disease problems was associated with the stresses of parturition and early lactation and/or with unusual environmental stress cofactors.

Job satisfaction reported by AS, BS degree radiographers.

This study evaluated the job satisfaction of graduates of a large radiography program in the Southeast, comparing the overall job satisfaction of those who had earned an associate degree with those who had earned both an associate and a baccalaureate degree. In general, both groups of radiographers exhibited a similarly high level of job satisfaction, showing no statistically significant differences. The results suggest that the baccalaureate degree, although important in providing specific skills and additional education for radiographers, may not directly affect radiographers' job satisfaction.

Adverse-event-reporting practices by US hospitals: results of a national survey.

CONTEXT: Little is known about hospitals' adverse-event-reporting systems, or how they use reported data to improve practices. This information is needed to assess effects of national patient-safety initiatives, including implementation of the Patient Safety and Quality Improvement Act of 2005 (PSQIA). This survey generated baseline information on the characteristics of hospital adverse-event-reporting systems and processes, for use in assessing progress in improvements to reporting. METHODS: The Adverse Event Reporting Survey, developed by Westat, was administered in September 2005 through January 2006, using a mixed-mode (mail/telephone) survey with a stratified random sample of 2050 non-federal US hospitals. Risk managers were the respondents. An 81% response rate was obtained, for a sample of 1652 completed surveys. RESULTS: Virtually all hospitals reported they have centralised adverse-event-reporting systems, although characteristics varied. Scores on four performance indexes suggest that only 32% of hospitals have established environments that support reporting, only 13% have broad staff involvement in reporting adverse events, and 20-21% fully distribute and consider summary reports on identified events. Because survey responses are self-reported by risk managers, these may be optimistic assessments of hospital performance. CONCLUSIONS: Survey findings document the current status of hospital adverse-event-reporting systems and point to needed improvements in reporting processes. PSQIA liability protections for hospitals reporting data to patient-safety organisations should also help stimulate improvements in hospitals' internal reporting processes. Other mechanisms that encourage hospitals to strengthen their reporting systems, for example, strong patient-safety programmes, also would be useful.

Quantifying change in distributions: a new departure index that detects, measures and describes change in distributions from population structures, size-classes and other ordered data.

Many statistics are available to compare distributions. Some are limited to nominal data while others, such as skew, Kullback-Leibler, Kolmogorov-Smirnov and the Gini coefficient, are useful for providing information about ordered distributions. While many of these tests are useful for determining properties of data in histograms, there has not been a test until now that allows for the detection of differences between distributions, describes the difference and is sensitive to the location of the departures. Such a test could be critical for comparing pre-and post-event distributions, such as a change in the distribution of biomass due to fire, for example, or for comparing data from different locations, such as soil size distributions, and even for evaluating economic disparity or examining differences in age demographics. We present a new statistic, a departure index, which allows a test distribution to be compared with any reference distribution. The resulting index contains information about the location, magnitude and direction of departure from the reference distribution to the test distribution. The departure index in turn provides a standardized response range that allows for a comparison of results from different analyses. A case study of actual fire data demonstrates the sensitivity and range of the test.