1,416 research outputs found
Seasonal Abundance, Movement and Diversity of Fishes in an Ozark Stream
Seasonal fluctuations in fish abundance in Mud Creek occurred throughout the year at all sampling stations. At the two upper stations abundance was high and unstable during winter and early spring and decreased after heavy rainfall in mid-April. Abundance was low throughout the summer months, increasing in the fall due to large numbers of young-of-the-year. However, a different seasonal cycle occurred at the lower station which included deeper pools. Numbers were low and stable throughout the winter and early spring but high and unstable during the summer. Bigeye shiners (Notropis boops) and bluntnose minnows (Pimephales notatus) were the most mobile species marked. Populations of brook silversides (Labidesthes sicculus) remained fairly isolated, stable, and showed little mobility. Mean species diversity fluctuated during the winter, spring, and fall; diversity values were highest and most stable during summer months when high and relatively stable numbers were collected. The main difference in mean species diversity between stations was the greater stability throughout the year at the upper station
Loss of Larval Fish by Epilimnial Discharge From DeGray Lake, Arkansas
Weekly samples of larval fish were collected from water discharged from the epilimnion of DeGray Lake into the tailwaters, for power generation, from April through August, 1976 and 1977. Peak rates of loss measured were 1.4 larvae/m³ in May, 1976 and 2.7/m³ in April, 1977. Sunfish, shad and crappie made up 97% of an estimated 83.3 million fish lost in 1976, and 98% of 122.4 million lost in 1977. The most critical period for larval fish loss extended from the last week of April to the first week of June. No definite relationships were noted between length of the power generation period or power generation rate, and rate of larval fish discharge. Diel collections showed the rate of larval fish discharge to be lower and more uniform during darkness than during daylight
Fishes of the Caddo River, Arkansas, After Impoundment of DeGray Lake
Fifty-five collections of fishes were made with small-mesh seines and electrofishing gear in the Caddo River and four of its tributaries during 1974-75. Eighty-two species representing 17 families were collected; 14 of the species had not previously been reported from the Caddo River
Development of an hp-version finite element method for computational optimal control
The purpose of this research effort was to begin the study of the application of hp-version finite elements to the numerical solution of optimal control problems. Under NAG-939, the hybrid MACSYMA/FORTRAN code GENCODE was developed which utilized h-version finite elements to successfully approximate solutions to a wide class of optimal control problems. In that code the means for improvement of the solution was the refinement of the time-discretization mesh. With the extension to hp-version finite elements, the degrees of freedom include both nodal values and extra interior values associated with the unknown states, co-states, and controls, the number of which depends on the order of the shape functions in each element. One possible drawback is the increased computational effort within each element required in implementing hp-version finite elements. We are trying to determine whether this computational effort is sufficiently offset by the reduction in the number of time elements used and improved Newton-Raphson convergence so as to be useful in solving optimal control problems in real time. Because certain of the element interior unknowns can be eliminated at the element level by solving a small set of nonlinear algebraic equations in which the nodal values are taken as given, the scheme may turn out to be especially powerful in a parallel computing environment. A different processor could be assigned to each element. The number of processors, strictly speaking, is not required to be any larger than the number of sub-regions which are free of discontinuities of any kind
Effect of a quality improvement programme on leadership, innovation and use of quality improvement methods in general practice
Introduction
Market mechanisms and pay-for-performance have failed to deliver continuing improvements in UK clinical care. Leadership and innovation are currently seen as essential to maintain and improve clinical quality but little is known about the relationship between these and the extent to which quality improvement (QI) methods are used in general practice. This study aimed to investigate the effect of quality improvement training on leadership behaviour, culture of innovation and adoption of QI methods in general practice.
Method
Self-administered postal questionnaires were sent to general practitioner quality leads in one UK county at the beginning (2007) and the end (2010) of a QI programme. The questionnaire consisted of background demographic information, a 12-item scale to assess leadership behaviour, a seven-dimension self-rating scale for innovation culture and questions on current use of quality improvement techniques and the effect of this on practice. We analysed change between the two surveys and the effect of participation in QI training.
Results
Sixty-three completed questionnaires (62%) were returned in 2007 and 47 (46%) in 2010; 32 practices completed both surveys. Although leadership behaviours were not commonly expressed, many practices reported a positive culture of innovation with significant positive correlation between leadership and innovation (r = 0.57; P < 0.001); apart from clinical audit and significant event analysis, QI methods were not reported as having been adopted by most participating practices. Percentage leadership score changed little over three years (increase 4.0 points, 95%CI -8.9 to 16.9) with little difference between participating and non-participating practices (7.6, -6.4 to 21.6) and no evidence of differential change (-1.5, -17.0 to 14.0). Percentage innovation culture scores showed a similar pattern (time -4.1 points, -15.1 to 6.9, group -1.6, -12.7 to 9.4, differential change 5.3, -7.8 to 18.5).
Conclusions
Leadership behaviours were infrequently reported, and despite describing a culture of innovation there was low uptake of QI methods beyond clinical and significant event audit even after practices participated in a QI programme. There is evidence that practices may need greater support to enhance leadership competences and develop quality improvement skills to stimulate innovation if improvements in health care are to accelerate
Recommended from our members
Persistent, symptomless, systemic, and seed-borne infection of lettuce by Botrytis cinerea
Experiments are presented which show that Botrytis cinerea, the cause of gray mould disease, is often present in symptomless lettuce plants as a systemic, endophytic, infection which may arise from seed. The fungus was isolated on selective media from surface sterilized sections of roots, stem pieces and leaf discs from symptomless plants grown in a conventional glasshouse and in a spore-free air-flow provided by an isolation propagator. The presence of B. cinerea was confirmed by immuno-labelling the tissues with the Botrytis-specific monoclonal antibody BC-12.CA4. As plants grew, infection spread from the roots to stems and leaves. Surface sterilization of seeds reduced the number of infected symptomless plants. Artificial infection of seedlings with dry conidia increased the rate of infection in some experiments. Selected isolates were genetically finger-printed using microsatellite loci. This confirmed systemic spread of the inoculating isolates but showed that other isolates were also present and that single plants hosted multiple isolates. This shows that B. cinerea commonly grows in lettuce plants as an endophyte, as has already been shown for Primula. If true for other hosts, the endophytic phase may be as important a component of the species population as the aggressive necrotrophic phase
Concanavalin A-Binding Enzymes of Crotalus scutulatus scutulatus Venom
Crotalus scutulatus scutulatus crude venom was separated into two fractions by Concanavalin A Sepharose 4B affinity chromatography. The proteins binding to Con A exhibited phosphomonoesterase (orthophosphoric monoester phosphohydrolase EC 3.1.3.2), phosphodiesterase, 5\u27-nucleotidase (5\u27-ribonucleotide phosphohydrolase EC 3.1.3.5), phospholipase A(phosphatidate 2-acylhydrolase EC 3.1.1 .4), hyaluronidase (hyaluronate glycanohydrolase EC 3.2.1 d), N-benzoyl-L-arginine ethyl esterase, p-toluenesulfonyl-L-arginine methyl esterase, L-amino acid oxidase (L-amino acid: 02 oxidoreductase [deaminating] EC 1.4.3.2), and caseinolytic activities. Thrombin-like and NAD nucleosidase (5\u27-ribonucleotide phosphohydrolase EC 3.1.3.5) activities were not observed. The crude venom and the fraction containing the glycoproteins which bound to Con A were fractionated by DEAE Sephadex A-50 ion exchange chromatography. Each of these samples yielded fractions having caseinolytic activities
Concanavalin A-Nonbinding Enzymes of Crotalus scutulatus scutulatus Venom
Crotalus scutulatus scutulatus crude venom was separated into two fractions by Concanavalin A Sepharose 4B affinity chromatography. The Concanavalin A-nonbinding fraction (F-l) exhibited phosphomonoesterase (orthophosphoric monoester phosphohydrolase EC 3.1 .3.2), phosphodiesterase, 5 \u27-nucleotidase (5 \u27-ribonucleotide phosphohydrolase EC 3.1.3.5), phospholipase A (phosphatidate 2-acylhydrolase EC 3.1.1.4), hyaluronidase (hyaluronate glycanohydrolase EC 3.2.1.d), N-benzoyl-Larginine ethyl esterase, p-toluenesulfonyl-L-arginine methyl esterase, L-amino acid oxidase (L-amino acid: O2 oxidoreductase [deaminating] EC 1.4.3.2), and caseinolytic activities. Thrombin-like and NAD nucleosidase (5 \u27-ribonudeotide phosphohydrolase EC 3.1.3.5) activities were not observed. DEAE Sephadex A-50 ion exchange chromatography by two stage elution of F-l yielded several fractions having proteinase activities. Proteinase activity was observed in the latter fractions of the first elution and in the fractions of the second elution
- …