2,145 research outputs found
An assessment of scup (Stenotomus chrysops) and black sea bass (Centropristas striata) discards in the directed otter trawl fisheries in the Mid-Atlantic Bight
This study was undertaken to re-assess the level of scup (Stenotomus chrysops) discards by weight and to evaluate the effect of various codend mesh sizes on the level of
scup discards in the winter-trawl scup fishery. Scup discards were high in directed scup tows regardless of
codend mesh â typically one to five times the weight of landings. The weight of scup discards in the present study did not differ significantly from that recorded in scup-targeted tows in the NMFS observer database. Most discards were required as such by the 22.86 cm TL (total length) fish-size limit for catches. Mesh sizes â€12.7 cm, including the current legal mesh size (11.43 cm) did not adequately filter out scup smaller than 22.86 cm. The median length of scup discards was about 19.83 cm TL. Lowering the legal size for scup from 22.86 to 19.83 cm TL would greatly reduce discard mortality. Scup discards were a small fraction (0.4%) of black sea bass (Centropristis striata) landings in blacksea-bassâtargeted tows. The black sea
bass fishery is currently regulated under the small-mesh fishery gearrestricted area plan in which fishing
is prohibited in some areas to reduce scup mortality. Our study found no evidence to support the efficacy of this management approach. The expectations that discarding would
increase disproportionately as the trip limit (limit [in kilograms] on catch for a species) was reached towards
the end of the trip and that discards would increase when the trip limit was reduced from 4536 kg to 454 kg at the end of the directed fishing season were not supported. Trip limits did not significantly affect discard mortality
Blood pressure variability: Epidemiological and clinical issues
Blood pressure variability (BPV) is a classical physiological phenomenon. This paper describesmajor epidemiological and clinical issues of BPV which may be important to understand thebackground of this interesting feature. In healthy subjects, BPV is a measure of hemodynamiccondition and refl ects function of autonomic nervous system. BP fl uctuations result from thecomplex interaction between environmental stimulation, genetic factors and cardiovascularcontrol mechanisms. Abnormal BPV is recognized in persons with a blurred dipping pattern(i.e. extreme dipping, non-dipping, reverse-dipping, morning surge of BP) or increased variationsof day-time or night-time BP (high BP lability). Inappropriate BPV worsens the outcome,including increase in all-cause and cardiac mortality and incidence of cardiovascular events,and advance in target organ damage. Abnormal BPV may be softened or removed with suitabletime-dependent administration of anti-hypertensive agents, especially those acting on thereninâangiotensin system
Left main disease management strategy: Indications and revascularization methods in particular groups of subjects
Surgical revascularization with coronary artery by-pass grafting is still recommended in vast majority of patients with unprotected left main disease. The aim of the paper was to analyze optimal treatment of left main disease in selected groups of patients, on the basis of current guidelines and information gained from literature data. We focused on data in relation to treatment of elderly patients, diabetics and those hemodynamically unstable. Additionally we discussed the issue of anti-platelet therapy and informed consent. As far as efficacy of treatment is concerned, not only method of revascularization but also general condition of the patient, the factors influencing peri-operative risk and optimal pharmacotherapy should be taken into account. Therefore establishment of the heart team is crucial when choosing the most suitable method of invasive treatment of left main disease
An integrated DC-DC step-up charge pump and step-down converter in 130 nm technology
After the LHC luminosity upgrade the number of readout channels in the ATLAS Inner Detector will be increased by one order of magnitude and delivering the power to the front-end electronics as well as cooling will become a critical system issue. Therefore a new solution for powering the readout electronics has to be worked out. Two main approaches for the power distribution are under development, the serial powering of a chain of modules and the parallel powering with a DCDC conversion stage on the detector. In both cases switchedcapacitor converters in the CMOS front-end chips will be used. In the paper we present the design study of a step-up charge pump and a step-down converter. In optimized designs power efficiency of 85 % for the step-up converter and 92 % for the step-down converter has been achieved
Aktualne koncepcje leczenia choroby pnia lewej tÄtnicy wieĆcowej: przeglÄ d danych epidemiologicznych
Compliance with pharmacological treatment among patients after minimally invasive coronary bypass grafting
Background: We sought to evaluate patientsâ adherence to optimal pharmacotherapy as recommended by the European Society of Cardiology, together with the assessment of potential clinical determinants of medical non-compliance in a large cohort of patients after endoscopic atraumatic coronary artery bypassing (EACAB).Methods: This cross sectional study was conducted in a group of 706 individuals who underwent EACAB between April 1998 and December 2010. Data covering current pharmacological treatment with antiplatelet agents, beta-blockers (BB) (or heart rate lowering calcium channel blockers [CCB] in case of intolerance and/or poor efficacy of beta-blockade), angiotensin-converting enzyme (ACE) inhibitors (or angiotensin receptor blockers [ARB]) and statins was acquired. Mean duration of observation after the surgery was 2132 ± 1313 days.Results: Complete follow-up data has been obtained from 415 living patients (341 males). Amongst them, 353 (85%) received antiplatelet agents, while BB or CCB were routinely ingested by 349 (84%) patients. Statins were used by 310 (74.7%) individuals and 274 (66%) subjects took ACE inhibitors or ARB. Baseline demographic and clinical features, including major co-morbidities had no impact on patientsâ compliance with all investigated medications. There was no clear association between adherence to treatment and risk of rehospitalization or occurrence of major cerebral and cardiovascular events.Conclusions: EACAB patientsâ compliance with pharmacotherapy guidelines is insufficient and is unrelated to demographic and clinical features of the subjects. Multidisciplinary approach involving health education, enhancement in prescription drug affordability and a better rapport between doctors and patients should be incorporated into clinical practice to overcome therapeutic disobedience
A fast radio burst associated with a Galactic magnetar
Since their discovery in 2007, much effort has been devoted to uncovering the sources of the extragalactic, millisecond-duration fast radio bursts (FRBs). A class of neutron stars known as magnetars is a leading candidate source of FRBs. Magnetars have surface magnetic fields in excess of 10Âč⎠gauss, the decay of which powers a range of high-energy phenomena5. Here we report observations of a millisecond-duration radio burst from the Galactic magnetar SGR 1935+2154, with a fluence of 1.5 ± 0.3 megajansky milliseconds. This event, FRB 200428 (ST 200428A), was detected on 28 April 2020 by the STARE2 radio array in the 1,281â1,468 megahertz band. The isotropic-equivalent energy released in FRB 200428 is 4 Ă 10Âł times greater than that of any radio pulse from the Crab pulsarâpreviously the source of the brightest Galactic radio bursts observed on similar timescales7. FRB 200428 is just 30 times less energetic than the weakest extragalactic FRB observed so far, and is drawn from the same population as the observed FRB sample. The coincidence of FRB 200428 with an X-ray burst favours emission models that describe synchrotron masers or electromagnetic pulses powered by magnetar bursts and giant flares. The discovery of FRB 200428 implies that active magnetars such as SGR 1935+2154 can produce FRBs at extragalactic distances
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