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Very few practical frameworks exist to guide the formulation of recommendations at hospital-based health technology assessment (HTA) units. The objectives of our study were: (i) to identify decision criteria specific to the context of hospital-based health technologies and interventions, (ii) to estimate the extent to which the expert community agrees on the importance of the identified criteria, (iii) to incorporate the identified criteria into a decision-aid tool, and (iv) to illustrate the application of a prototype decision-aid tool.
Relevant decision criteria were identified using existing frameworks for HTA recommendations, our past experience, a literature search, and feedback from a survey of diverse stakeholders.
Based on the survey results, twenty-three decision criteria were incorporated into the final framework. We defined an approach that eschewed a scoring system, but instead relied on a visual means for arriving at a final recommendation, by juxtaposing the importance rating for each criterion against the results of the health technology assessment. For a technology to be approved, a majority of criteria considered important should also have received favorable findings.
We created a simple and practical decision-aid tool that incorporates all decision criteria relevant to a hospital-based HTA unit. With its ease of use and accessibility, our tool renders the subjective decision-making process more structured and transparent.
As apex predators, sharks are known to play an important role in marine food webs. Detailed information on their diet and trophic level is however needed to make clear inferences about their role in the ecosystem. A total of 335 stomachs of smooth hammerhead sharks, Sphyrna zygaena, were obtained from commercial fishing vessels operating in the Ecuadorian Pacific between January and December 2004. A total of 53 prey items were found in the stomachs. According to the Index of Relative Importance (%IRI), cephalopods were the main prey (Dosidicus gigas, Sthenoteuthis oualaniensis, Ancistrocheirus lesueurii and Lolliguncula [Loliolopsis] diomedeae). Sphyrna zygaena was thus confirmed to be a teutophagous species. The estimated trophic level of S. zygaena was between 4.6 and 5.1 (mean ± SD: 4.7 ± 0.16; males: 4.7; females: 4.8). Levin's index (BA) was low (overall: 0.07; males: 0.08; females: 0.09), indicating a narrow trophic niche. We found that sharks <150 cm in total length consumed prey of coastal origin, whereas sharks ≥150 cm foraged in oceanic waters and near the continental shelf. The analyses indicate that S. zygaena is a specialized predator consuming mainly squids.
The shovelnose guitarfish (Pseudobatos productus) is the most abundant and economically important batoid in Gulf of California fisheries. Despite the importance of the guitarfish in the demersal ecosystem, its trophic relationships are poorly understood. Results from stomach content and stable isotope analysis indicate P. productus is a specialist predator that feeds on coastal benthic organisms, mainly crustaceans, followed by fishes and cephalopods in the Upper Gulf of California. Males and females did not differ in dietary composition and isotopic values. Pseudobatos productus displayed ontogenetic changes in the diet, with smaller, immature individuals having a more specialized diet and mature individuals becoming generalist predators. Size classes I (<570 mm) and II (>570 mm) fed almost exclusively on crustaceans (99.78% and 82.37 %IRI, respectively). Size class III (>832 mm) increased consumption of fishes (22.11 %IRI) and squid (6.54 %IRI). Ontogenetic diet shifts were strongly supported by the SIAR mixing model. Stomach content and stable isotope analyses classify P. productus as a second-order predator.
This article presents the key results of a major survey carried out by the NEARCH project on the public perception of archaeology and heritage across Europe. The analysis focuses on three main points of significance for contemporary archaeological practice. The first is the image of archaeology and its definition in the perception of the general public. The second concerns the values that archaeology represents for the public. The third focuses on the social expectations placed on archaeologists and archaeology. The NEARCH survey clearly indicates that there is a significant public expectation by Europeans that archaeology should work comprehensively across a broad range of areas, and that cultural heritage management in general needs to engage more with different archaeological and heritage groups.
Potassium titanyl phosphate crystals in both x-cut and z-cut were irradiated with 185 MeV Au ions. The morphology of the resulting ion tracks was investigated using small angle x-ray scattering (SAXS), transmission electron microscopy (TEM), and atomic force microscopy (AFM). SAXS measurements indicate the presence of cylindrical ion tracks with abrupt boundaries and a density contrast of 1 ± 0.5% compared to the surrounding matrix, consistent with amorphous tracks. The track radius depends on the crystalline orientation, with 6.0 ± 0.1 nm measured for ion tracks along the x-axis and 6.3 ± 0.1 nm for those along the z-axis. TEM images in both cross-section and plan-view show amorphous ion tracks with radii comparable to those determined from SAXS analysis. The protruding hillocks covering the sample surface detected by AFM are consistent with a lower density of the amorphous material within the ion tracks compared to the surrounding matrix. Simulations using an inelastic thermal-spike model indicate that differences in the thermal conductivity along the z- and x-axis can partially explain the different track radii along these directions.
Habitat loss and fragmentation are affecting populations of forest dwelling mammalian carnivores worldwide. In southern Chile, a biodiversity hotspot, anthropogenic activities have resulted in high loss of native forest cover. The guiña, or kodkod cat, Leopardus guigna is a small forest-dwelling felid with a narrow range in the temperate forest of southern Chile. The few existing studies of the species have suggested that it is almost exclusively restricted to large tracts of native forest. This paper reports a study in the temperate forest within a fragmented Andean piedmont landscape which demonstrates that smaller forest fragments in the farmland matrix are playing a key role in the persistence of the guiña. We estimated occupancy in both continuous native forest and remnant forest fragments and, with single-species/single-season models, evaluated the extent to which forest cover, habitat type and proximity to protected areas have a modulating effect on occupancy. A continuous survey during 2008–2009, in three seasons of 90–100 days each, accumulated 6,200 camera trap days and returned 47 photographs of guiña. Total detection in fragments was higher than in continuous forests, with detection confirmed in almost 70% of studied fragments. We found that probability of a site being occupied significantly increased with forest cover (adult/secondary forest, scrubland) and probability was low (< 0.2) in sites with < 50% of surrounding forest cover. Our study highlights the importance of remnant forest fragments in the mosaic of extensive agriculture for the spatial dynamics of a guiña population and hence for the future conservation of the species.
We prove that the Brauer–Manin obstruction is the only obstruction to the existence of integral points on affine varieties over global fields of positive characteristic
. More precisely, we show that the only obstructions come from étale covers of exponent
or, alternatively, from flat covers coming from torsors under connected group schemes of exponent
We discuss the question of whether the Brauer–Manin obstruction is the only obstruction to the Hasse principle for integral points on affine hyperbolic curves. In the case of rational curves we conjecture a positive answer, we prove that this conjecture can be given several equivalent formulations and we relate it to an old conjecture of Skolem. Finally, we show that for elliptic curves minus one point a strong version of the question (describing the set of integral points by local conditions) has a negative answer.
Objective: To evaluate immediate and midterm results with percutaneous aortic valvoplasty. Material and Methods: We reviewed the records of 141 patients undergoing percutaneous aortic valvopasty over a period of 13 years. Results: The patients were aged from 2 months to 40 years, with a mean of 10.9 ± 9.9 years. Of the total, 90 (63%) were male. The initial systolic peak-to-peak gradient decreased from 163 ± 52 mmHg to 32 ± 18 mmHg (p > 0.01) after valvoplasty in all 141 patients, while the proportional reduction ranged from 0 to 100%, with a mean of 72 ± 27%. The index of the size of the balloon to the diameter of the valvar orifice was 0.88 ± 0.19 in 128 patients. The follow-up ranged from 6 to 168 months, with a mean 51 ± 48 months in 70 patients. A significant difference was found in those failing after dilation when the initial evaluation was compared to the final evaluation of patients with follow-up. In those failing, the number of patients rose from 12 (17%) to 21 (30%) (p > 0.01). In contrast, in those in whom we achieved success, there was not such a great difference between the initial and final evaluation: 58 (83%) versus 49 (70%) (p > 0.1). The actuarial freedom curve of patients not needing new percutaneous aortic valvoplasty or surgery, by 182 months, was at 87% and 82% respectively. Conclusion: We have reviewed the largest series of patients in Latin-America reported thus far after undergoing percutaneous aortic valvoplasty, concentrating on mid term follow-up and limitations. New prospective and multicentric studies are needed from our region.
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