Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
IEEE Trans Vis Comput Graph ; 29(1): 657-667, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36260569

RESUMEN

The overdraw problem of scatterplots seriously interferes with the visual tasks. Existing methods, such as data sampling, node dispersion, subspace mapping, and visual abstraction, cannot guarantee the correspondence and consistency between the data points that reflect the intrinsic original data distribution and the corresponding visual units that reveal the presented data distribution, thus failing to obtain an overlap-free scatterplot with unbiased and lossless data distribution. A dual space coupling model is proposed in this paper to represent the complex bilateral relationship between data space and visual space theoretically and analytically. Under the guidance of the model, an overlap-free scatterplot method is developed through integration of the following: a geometry-based data transformation algorithm, namely DistributionTranscriptor; an efficient spatial mutual exclusion guided view transformation algorithm, namely PolarPacking; an overlap-free oriented visual encoding configuration model and a radius adjustment tool, namely frdraw. Our method can ensure complete and accurate information transfer between the two spaces, maintaining consistency between the newly created scatterplot and the original data distribution on global and local features. Quantitative evaluation proves our remarkable progress on computational efficiency compared with the state-of-the-art methods. Three applications involving pattern enhancement, interaction improvement, and overdraw mitigation of trajectory visualization demonstrate the broad prospects of our method.

2.
Animals (Basel) ; 12(7)2022 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-35405867

RESUMEN

The effects of restricted grazing durations on the gastrointestinal development and carcass quality of growing lambs are poorly understood. In this study, 32 lambs were randomly assigned to four groups (n = 8, body weight = 21.86 kg) corresponding to 2, 4, 8 and 12 h of grazing per day. When off-pasture, all lambs were housed and fed concentrate and hay. When the grazing time decreased from 12 h to 2 h, the abomasum weight and large intestine length decreased (p = 0.019; p = 0.069). Compared to lambs grazed for 12 h, animals grazed for 2−4 h had a greater villus height and villus-to-crypt ratio in the duodenum, jejunum and ileum segments (p < 0.05); the 2 h lambs had superior carcass quality and a smaller diameter and area of the gluteus medium muscle fibers (p < 0.05), with no significant change after 4 h of grazing. The results indicated that shorter grazing times and supplementation were beneficial for the gastrointestinal tract development and carcass quality of growing lambs. Therefore, a better grazing management approach in Inner Mongolia could be to restrict the grazing of lambs to 4 h per day instead of grazing for more extended periods.

3.
Front Microbiol ; 13: 1108890, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36713149

RESUMEN

Introduction: Ensiling whole-crop oat (Avena sativa L.) has attracted a growing interest in the Qinghai-Tibet Plateau. The study aimed to investigate the microbial community and chemical composition of fresh and ensiling oat harvested from six different elevations of the Qinghai-Tibet Plateau. Method: The oat (A. sativa L. cv. Qingyin No. 1) was planted in six different sites across Qinghai-Tibet Plateau (BM, Bomi County; BY, Bayi County; DZ, Dazi County; BR, Biru County; SC, Suo County; SN, Seni County), where the elevations were in the range of 2,800-4,500 m above sea level (a. s. l.). Oat was harvested at the milk stage and ensiled for 90 days. Results: The highest crude protein (CP) and lowest water-soluble carbohydrate (WSC) were observed in fresh oat of SN and BM, respectively, however, no distinct gradient trend in WSC and CP concentrations along the elevation gradient. The lowest LAB counts in fresh oat from the highest elevational regions of SN. After 90 days of ensiling, the pH in all oat silages was lower than 4.2, and silages from SC and SN showed a lower pH and butyric acid concentration, and higher lactic acid (LA) concentration than silages of other regions. The oat silage from BR showed the lowest LA concentration and the highest pH. The bimodal distributions of fungal and bacterial richness in fresh oat along the elevation gradient were observed, while the elevation gradients did not affect the fungal Shannon index in fresh oat. Dioszegia, Cladosporium, and Vishniacozyma were the prevalent fungal genus in fresh oat, while Wickerhamomyces, Candida, and Saccharomyces dominated the fungal communities of silages. Wickerhamomyces and Candida were the dominant genera in oat silages from BM and SC, respectively. Erwinia, Paenibacillus, Pseudomonas, Leuconostoc, and Exiguobacterium dominated the bacterial community of fresh oat, while Lactobacillus and Kosakonia were the dominant bacterial genus in oat silages. Pantoea was the most dominant bacterial genus in fresh oat from low-elevational regions (BM, BY, and DZ). Oat from SN exhibited the best fermentation quality although fresh oat of SN hosted the lowest LAB counts, indicating that high-efficient LAB might be present in fresh oat sampled from high altitudes.

4.
Opt Express ; 26(7): 7920-7933, 2018 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-29715766

RESUMEN

We demonstrate a III-V/silicon hybrid external cavity laser with a tuning range larger than 60 nm at the C-band on a silicon-on-insulator platform. A III-V semiconductor gain chip is hybridized into the silicon chip by edge-coupling the silicon chip through a Si3N4 spot size converter. The demonstrated packaging method requires only passive alignment and is thus suitable for high-volume production. The laser has a largest output power of 11 mW with a maximum wall-plug efficiency of 4.2%, tunability of 60 nm (more than covering the C-band), and a side-mode suppression ratio of 55 dB (>46 dB across the C-band). The lowest measured linewidth is 37 kHz (<80 kHz across the C-band), which is the narrowest linewidth using a silicon-based external cavity. In addition, we successfully demonstrate all silicon-photonics-based transmission of 34 Gbaud (272 Gb/s) dual-polarization 16-QAM using our integrated laser and silicon photonic coherent transceiver. The results show no additional penalty compared to commercially available narrow linewidth tunable lasers. To the best of our knowledge, this is the first experimental demonstration of a complete silicon photonic based coherent link. This is also the first experimental demonstration of >250 Gb/s coherent optical transmission using a silicon micro-ring-based tunable laser.

5.
J Smok Cessat ; 13(4): 227-232, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31452822

RESUMEN

INTRODUCTION: Because of financial pressures, low-income individuals sometimes run out of cellphone service towards the end of the month. AIMS: To determine if the time of month affects ability to reach low-income smokers by telephone. METHODS: We reviewed data from a completed trial in the United States of emergency department (ED)-initiated tobacco dependence treatment for low-income smokers at a busy, academic ED in an urban community. We recorded the date of each one-month follow-up call, and divided each month into four time blocks: Week 1, Week 2, Week 3, and Week 4. RESULTS: A total of 2,049 phone calls were made to reach 769 participants. Of these calls, 677 (33%) resulted in contact; 88% of all participants were contacted. Using generalised estimating equations with Week 4 as reference, the odds of a successful contact at Weeks 1, 2, and 3 were, respectively, 1.52 (95% CI 1.18, 1.96), 1.30 (95% CI 1.01, 1.66), and 1.37 (95% CI 1.07, 1.76). CONCLUSIONS: Study participants became progressively difficult to reach. This result may reflect low-income smokers' decreased rates of active telephone service later in the month and suggests a mechanism to improve follow-up rates in future studies of low-income populations.

6.
Curr Med Res Opin ; 34(2): 197-207, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28696793

RESUMEN

OBJECTIVE: To evaluate the hyperlipidemia prevention programs and policies in different countries and highlight the need of reforming the hyperlipidemia prevention policies in China to lower the growing cardiovascular disease (CVD) risk. RESEARCH DESIGN AND METHODS: PubMed, Google Scholar and Cochrane were searched for global hyperlipidemia prevention policies. Government-funded policies pertaining to lipid management were considered for this review. Only those studies that evaluated the success of prevention policies on the basis of: (i) achievement of hyperlipidemia targets; (ii) improvement in Cardiovascular (CV) risk reduction; and (iii) outcomes with reduction in hyperlipidemia after implementation of the policy, were included. RESULTS: Several global policies and programs aimed to improve CV health by highlighting lipid profile management. Implementation of the global and national policies led to improvement in cholesterol related outcomes such as availability of diagnostic measures, awareness of the risk factors, decrease in cholesterol levels, achieving healthy lifestyle to prevent CVD and improvement in availability of hypolipidemic medications, etc. Statins have been covered under reimbursement policies in many countries to improve usage and thereby preventing incidence of stroke and CVD. We observed a need for introducing new programs in China as the ongoing hyperlipidemia management policies are inadequate. The World Bank Report 2016 recommended that prevention policies in China be modeled on the US Million Hearts program. CONCLUSIONS: New hyperlipidemia prevention policies must set a time-bound target, and need to be patient and clinician centric in terms of applications, and revised periodically for long-term benefits.


Asunto(s)
Enfermedades Cardiovasculares , Salud Global/estadística & datos numéricos , Política de Salud , Hiperlipidemias , Hipolipemiantes/farmacología , Servicios Preventivos de Salud , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/prevención & control , China/epidemiología , Humanos , Hiperlipidemias/tratamiento farmacológico , Hiperlipidemias/epidemiología , Evaluación de Necesidades , Servicios Preventivos de Salud/métodos , Servicios Preventivos de Salud/organización & administración
7.
Opt Lett ; 39(16): 4703-6, 2014 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-25121853

RESUMEN

We present an ultracompact (15.3 µm long) and high-efficiency silicon-on-insulator polarization rotator designed for polarization-diversified circuits. The rotator is comprised of a bilevel-tapered TM0-to-TE1 mode converter and a novel bent-tapered TE1-to-TE0 mode converter. The rotator has a simulated polarization conversion loss lower than 0.2 dB and a polarization-extinction ratio larger than 25 dB over a wavelength range of 80 nm around 1550 nm. The rotator has a SiO2 top-cladding and can be fabricated in a CMOS-compatible process.

8.
Opt Express ; 22(3): 2489-96, 2014 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-24663541

RESUMEN

We present a highly efficient polarization splitter and rotator (PSR), fabricated using 248 nm deep ultraviolet lithography on a silicon-on-insulator substrate. The PSR is based on a double-etched directional coupler with a length of 27 µm. The fabricated PSR yields a TM-to-TE conversion loss better than 0.5 dB and TE insertion loss better than 0.3 dB, with an ultra-low crosstalk (-20 dB) in the wavelength regime 1540-1570 nm.

9.
Ther Innov Regul Sci ; 48(3): 362-366, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-30235531

RESUMEN

BACKGROUND: Regulators from the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA) do not always agree on interpretation of data for a drug's safety and efficacy. METHODS AND RESULTS: The authors compared all new molecular entities approved or rejected in a 5-year period from 2007 to 2011, identified where FDA and EMA reviews resulted in different regulatory decisions, and explored potential mechanisms for the discrepancies. Thirteen entities were associated with different regulatory decisions, and 2 drugs were withdrawn from their respective markets in 2010: one from the US (Mylotarg; gemtuzumab ozogamicin) and the other in Europe (Thelin; sitaxentan sodium). CONCLUSIONS: There are relatively few cases where FDA and EMA substantively differ with regard to product approvals and market withdrawals. It is likely that the scientific and cultural differences between FDA and EMA will continue to diminish over time, because these two agencies increasingly work together as pharmaceutical product development increasingly becomes a global endeavor.

10.
Opt Express ; 21(25): 31019-28, 2013 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-24514676

RESUMEN

We experimentally demonstrate a polarization splitting grating coupler that is operational near 1310 nm and 1550 nm in a silicon-on-insulator platform, using the same fiber angle for both wavelength bands. At 1550 nm, the device has an insertion loss of 7.1 dB and a 1.5-dB transmission window of 35 nm. At 1310 nm, the insertion loss and 1.5-dB transmission window are 8.2 dB and 18 nm, respectively. Polarization isolation at 1550 nm is 24 dB. This is the first experimental demonstration of a bi-wavelength polarization-splitting grating coupler.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...