Regulated power supply Patent

Design, development, and operating principles of power supply with starting circuit which is independent of voltage regulato

Review: NORTH AMERICAN DUCKS, GEESE & SWANS: IDENTIFICATION GUIDE. Frank S. Todd.

The North American Duck, Geese & Swans: Identification Guide, released in 2018, is the culmination of a lifetime of waterfowl photography by the late Frank Todd. Indeed, this book stands apart from other identification guides as being entirely photo-driven, with minimal introductory material, notations of field marks, or descriptions of the various waterfowl species. It is small enough to be carried in the field (6.5” × 9” × 0.5”), but most readers will find it less useful than a standard bird identification book (Sibley 2014), even for waterfowl. As the title suggests, the Todd guide focuses on North American species, but also includes an opportunistic sample of some vagrants. The sheer number of photographs is impressive (even overwhelming at times), and this guide would make a colorful addition to the libraries of amateur waterfowl enthusiasts across North America. The book format is straightforward: each group of birds (e.g., dabbling ducks, sea ducks) begins with a conversational paragraph that provides an entry-level description of basic life history and behavior. Within taxonomic groupings, each species that follows is allotted 1–3 pages with a small range map, one line of morphological measurements, four bullet points of identification tips, and an estimated North American population size that sometimes includes worldwide estimates. The overwhelming majority of each species account is composed of 5–45 photos of the bird in question. Interestingly, the photos themselves have been clipped to silhouettes in photo-editing software, i.e., ducks are “floating” on a monochromatic page rather than swimming on the water or flying through the air as they were in the original photograph. This cropping method is similar to that used in the Crossley ID Guide: Waterfowl, but Crossley et al. (2017) set collages of clipped photographs into a realistic photo backdrop to highlight the habitat in which species are commonly observed

Vegetation phenology and nest survival: Diagnosing heterogeneous effects through time

bias; duck; grassland; mallard; prairie; Robel; waterfowl; WATERFOWL PRODUCTION; HABITAT SELECTION; ARTIFICIAL NESTS; MOTTLED DUCKS; WINTER-WHEAT; SUCCESS; NORTH; PREDATION; CONCEALMENT; FIELD

Cover Use and Activity Time Budget of Blue-Winged Teal, Mallard, and Pintail Broods

Blue-winged teal (Anas discors), mallard (A. platyrhynchos), and pintail (A. acuta) broods were observed on 17 days between 25 June and 30 July, 1976. Brood activities and cover uses were recorded continuously from first light until dark. Observations of 269 broods from three wetlands were evaluated by species and brood age-class. Activity time budgets revealed significant (p\u3c.01) age specific differences in total feeding time and visibility among age-classes of all species combined and age-classes of blue-winged teal broods. Feeding modes also varied among age-classes. Daily patterns of cover use varied among brood age-classes and species. Morning and evening feeding peaks became more pronounced, and overall visibility increased, with brood age. Interspecific differences in daily activity patterns were observed among broods of the same age-class. Duration of active periods increased with age in blue-winged teal broods. Active periods recurred at regular intervals in all broods throughout the day, suggestive of polycyclic behavior patterns similar to those of adult ducks. A progressive increase in brood visibility was attributed primarily to seasonal changes in brood age structure and to wetland water loss. Temperature and wind speed influenced brood visibility during most observation days. Climatic conditions favorable to nighttime brood activity influenced brood behavior during the following day. Accuracy of present brood inventory techniques could be improved if considerations were made for brood behavior patterns and environmental factors which alter brood cover use

Participar de la extensión en el LVM en clave nodocente

El presente trabajo se propone compartir la experiencia como integrantes nodocentes en uno de los Proyectos de Extensión que están llevándose a cabo actualmente en el Liceo “Víctor Mercante”.Liceo "Víctor Mercante

Can sacrificial feeding areas protect aquatic plants from herbivore grazing? Using behavioural ecology to inform wildlife management

Effective wildlife management is needed for conservation, economic and human well-being objectives. However, traditional population control methods are frequently ineffective, unpopular with stakeholders, may affect non-target species, and can be both expensive and impractical to implement. New methods which address these issues and offer effective wildlife management are required. We used an individual-based model to predict the efficacy of a sacrificial feeding area in preventing grazing damage by mute swans (Cygnus olor) to adjacent river vegetation of high conservation and economic value. The accuracy of model predictions was assessed by a comparison with observed field data, whilst prediction robustness was evaluated using a sensitivity analysis. We used repeated simulations to evaluate how the efficacy of the sacrificial feeding area was regulated by (i) food quantity, (ii) food quality, and (iii) the functional response of the forager. Our model gave accurate predictions of aquatic plant biomass, carrying capacity, swan mortality, swan foraging effort, and river use. Our model predicted that increased sacrificial feeding area food quantity and quality would prevent the depletion of aquatic plant biomass by swans. When the functional response for vegetation in the sacrificial feeding area was increased, the food quantity and quality in the sacrificial feeding area required to protect adjacent aquatic plants were reduced. Our study demonstrates how the insights of behavioural ecology can be used to inform wildlife management. The principles that underpin our model predictions are likely to be valid across a range of different resource-consumer interactions, emphasising the generality of our approach to the evaluation of strategies for resolving wildlife management problems

Post-hatching parental care behaviour and hormonal status in a precocial bird

In birds, the link between parental care behaviour and prolactin release during incubation persists after hatching in altricial birds, but has never been precisely studied during the whole rearing period in precocial species, such as ducks. The present study aims to understand how changes in parental care after hatching are related to circulating prolactin levels in mallard hens rearing ducklings. Blood was sampled in hens over at least 13 post-hatching weeks and the behaviour of the hens and the ducklings was recorded daily until fledging. Contacts between hens and the ducklings, leadership of the ducklings and gathering of them steadily decreased over post-hatching time. Conversely, resting, preening and agonistic behaviour of hens towards ducklings increased. Plasma prolactin concentrations remained at high levels after hatching and then fell after week 6 when body mass and structural size of the young were close to those of the hen. Parental care behaviour declined linearly with brood age, showed a disruption of the hen-brood bond at week 6 post-hatching and was related to prolactin concentration according to a sigmoid function. Our results suggest that a definite threshold in circulating prolactin is necessary to promote and/or to maintain post-hatching parental care in ducks

Sternal plate fixation for sternal wound reconstruction: initial experience (Retrospective study)

<p>Abstract</p> <p>Background</p> <p>Median sternotomy infection and bony nonunion are two commonly described complications which occur in 0.4 - 5.1% of cardiac procedures. Although relatively infrequent, these complications can lead to significant morbidity and mortality. The aim of this retrospective study is to evaluate the initial experience of a transverse plate fixation system following wound complications associated with sternal dehiscence with or without infection following cardiac surgery.</p> <p>Methods</p> <p>A retrospective chart review of 40 consecutive patients who required sternal wound reconstruction post sternotomy was performed. Soft tissue debridement with removal of all compromised tissue was performed. Sternal debridement was carried using ronguers to healthy bleeding bone. All patients underwent sternal fixation using three rib plates combined with a single manubrial plate (Titanium Sternal Fixation System^®, Synthes). Incisions were closed in a layered fashion with the pectoral muscles being advanced to the midline. Data were expressed as mean ± SD, Median (range) or number (%). Statistical analyses were made by using Excel 2003 for Windows (Microsoft, Redmond, WA, USA).</p> <p>Results</p> <p>There were 40 consecutive patients, 31 males and 9 females. Twenty two patients (55%) were diagnosed with sternal dehiscence alone and 18 patients (45%) with associated wound discharge. Thirty eight patients went on to heal their wounds. Two patients developed recurrent wound infection and required VAC therapy. Both were immunocompromised. Median post-op ICU stay was one day with the median hospital stay of 18 days after plating.</p> <p>Conclusion</p> <p>Sternal plating appears to be an effective option for the treatment of sternal wound dehiscence associated with sternal instability. Long-term follow-up and further larger studies are needed to address the indications, benefits and complications of sternal plating.</p

Risk analysis and outcome of mediastinal wound and deep mediastinal wound infections with specific emphasis to omental transposition

<p>Abstract</p> <p>Background</p> <p>To report our experience, with Deep mediastinal wound infections (DMWI). Emphasis was given to the management of deep infections with omental flaps</p> <p>Methods</p> <p>From February 2000 to October 2007, out of 3896 cardiac surgery patients (prospective data collection) 120 pts (3.02%) developed sternal wound infections. There were 104 males & 16 females; (73.7%) CABG, (13.5%) Valves & (9.32%) CABG and Valve.</p> <p>Results</p> <p>Superficial sternal wound infection detected in 68 patients (1.75%) and fifty-two patients (1.34%) developed DMWI. The incremental risk factors for development of DMWI were: Diabetes (OR = 3.62, CI = 1.2-10.98), Pre Op Creatinine > 200 μmol/l (OR = 3.33, CI = 1.14-9.7) and Prolong ventilation (OR = 4.16, CI = 1.73-9.98). Overall mortality for the DMWI was 9.3% and the specific mortality of the omental flap group was 8.3%. 19% of the "DMWI group", developed complications: hematoma 6%, partial flap loss 3.0%, wound dehiscence 5.3%. Mean Hospital Stay: 59 ± 21.5 days.</p> <p>Conclusion</p> <p>Post cardiac surgery sternal wound complications remain challenging. The role of multidisciplinary approach is fundamental, as is the importance of an aggressive early wound exploration especially for deep sternal infections.</p