379 research outputs found
An annotated bibliography of aquatic sediment traps and trapping methods
This annotated bibliography is intended to give as reasonably complete a review of the existing literature as possible, and to offer some practical guidance in the selection and operation of sediment traps in future monitoring programmes
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Image compression using the W-transform
The authors present the W-transform for a multiresolution signal decomposition. One of the differences between the wavelet transform and W-transform is that the W-transform leads to a nonorthogonal signal decomposition. Another difference between the two is the manner in which the W-transform handles the endpoints (boundaries) of the signal. This approach does not restrict the length of the signal to be a power of two. Furthermore, it does not call for the extension of the signal thus, the W-transform is a convenient tool for image compression. They present the basic theory behind the W-transform and include experimental simulations to demonstrate its capabilities
Simplified Multistep Outflow Method to Estimate Unsaturated Hydraulic Functions for Coarse-Textured Soils
Although the multistep outfl ow (MSO) method is well suited for the estimation of soil hydraulic properties by
inverse solution techniques, this method has not been widely adopted because it requires advanced instrumentation
and is time consuming. Th e objective of this study was to develop a modifi ed version of the multistep outfl ow
technique that largely simplifi es laboratory procedures and reduces costs and time. Th e numerical inversion
procedures require applying user-friendly HYDRUS soft ware to estimate fi tting parameters for soil water retention
and unsaturated hydraulic conductivity curves. Whereas values of saturated water content and saturated hydraulic
conductivity must be measured independently, the remaining functional parameters are estimated using an inverse
solution of a transient drainage experiment using multiple suction steps and a hanging water column, with drainage
outfl ows measured during drainage. A comparison test showed that the simplifi ed experiment without tensiometric
measurements provided suffi cient information in the parameter identifi cation compared with a traditional pressure
outfl ow experiment with tensiometric measurements for an Oso Flaco sand and a loamy sand fi eld soil in the
suction range of 0 to 17 kPa
Continuation-Passing C: compiling threads to events through continuations
In this paper, we introduce Continuation Passing C (CPC), a programming
language for concurrent systems in which native and cooperative threads are
unified and presented to the programmer as a single abstraction. The CPC
compiler uses a compilation technique, based on the CPS transform, that yields
efficient code and an extremely lightweight representation for contexts. We
provide a proof of the correctness of our compilation scheme. We show in
particular that lambda-lifting, a common compilation technique for functional
languages, is also correct in an imperative language like C, under some
conditions enforced by the CPC compiler. The current CPC compiler is mature
enough to write substantial programs such as Hekate, a highly concurrent
BitTorrent seeder. Our benchmark results show that CPC is as efficient, while
using significantly less space, as the most efficient thread libraries
available.Comment: Higher-Order and Symbolic Computation (2012). arXiv admin note:
substantial text overlap with arXiv:1202.324
Fifteen-year trends in management and outcomes of non–ST-segment–elevation myocardial infarction among black and white patients: The ARIC community surveillance study, 2000–2014
Background—Standardization of evidence-based medical therapies has improved outcomes for patients with non–ST-segment– elevation myocardial infarction (NSTEMI). Although racial differences in NSTEMI management have previously been reported, it is uncertain whether these differences have been ameliorated over time. Methods and Results—The ARIC (Atherosclerosis Risk in Communities) Community Surveillance study conducts hospital surveillance of acute myocardial infarction in 4 US communities. NSTEMI was classified by physician review, using a validated algorithm. From 2000 to 2014, 17 755 weighted hospitalizations for NSTEMI (patient race: 36% black, 64% white) were sampled by ARIC. Black patients were younger (aged 60 versus 66 years), more often female (45% versus 38%), and less likely to have medical insurance (88% versus 93%) but had more comorbidities. Black patients were less often administered aspirin (85% versus 92%), other antiplatelet therapy (45% versus 60%), b-blockers (85% versus 88%), and lipid-lowering medications (68% versus 76%). After adjustments, black patients had a 24% lower probability of receiving nonaspirin antiplatelets (relative risk: 0.76; 95% confidence interval, 0.71–0.81), a 29% lower probability of angiography (relative risk: 0.71; 95% confidence interval, 0.67–0.76), and a 45% lower probability of revascularization (relative risk: 0.55; 95% confidence interval, 0.50–0.60). No suggestion of a changing trend over time was observed for any NSTEMI therapy (P values for interaction, all >0.20). Conclusions—This longitudinal community surveillance of hospitalized NSTEMI patients suggests black patients have more comorbidities and less likelihood of receiving guideline-based NSTEMI therapies, and these findings persisted across the 15-year period. Focused efforts to reduce comorbidity burden and to more consistently implement guideline-directed treatments in this high-risk population are warranted
Influência da altura de pastejo de azevém e aveia em atributos fÃsicos de um Latossolo Vermelho distroférrico, após sete anos sob integração lavoura-pecuária
Infiltração de atrazina em latossolo submetido aos sistemas de plantio direto e convencional
Resident Cellular Components of the Human Lung Current Knowledge and Goals for Research on Cell Phenotyping and Function
The purpose of the workshop was to identify still obscure or novel cellular components of the lung, to determine cell function in lung development and in health that impacts on disease, and to decide promising avenues for future research to extract and phenotype these cells. Since robust technologies are now available to identify, sort, purify, culture, and phenotype cells, progress is now within sight to unravel the origins and functional capabilities of lung cells in developmental stages and in disease. The Workshop's agenda was to first discuss the lung's embryologic development, including progenitor and stem cells, and then assess the functional and structural cells in three main compartments of the lung: (1) airway cells in bronchial and bronchiolar epithelium and bronchial glands (basal, secretory, ciliated, Clara, and neuroendocrine cells); (2) alveolar unit cells (Type 1 cells, Type 2 cells, and fibroblasts in the interstitium); and (3) pulmonary vascular cells (endothelial cells from different vascular structures, smooth muscle cells, and adventitial fibroblasts). The main recommendations were to: (1) characterize with better cell markers, both surface and nonsurface, the various cells within the lung, including progenitor cells and stem cells; (2) obtain more knowledge about gene expression in specific cell types in health and disease, which will provide insights into biological and pathologic processes; (3) develop more methodologies for cell culture, isolation, sorting, co-culture, and immortalization; and (4) promote tissue banks to facilitate the procurement of tissue from normal and from diseased lung for analysis at all levels
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