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1.
J Environ Manage ; 351: 119615, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38091728

RESUMO

High-resolution mapping of rice fields is crucial for understanding and managing rice cultivation in countries like Bangladesh, particularly in the face of climate change. Rice is a vital crop, cultivated in small scale farms that contributes significantly to the economy and food security in Bangladesh. Accurate mapping can facilitate improved rice production, the development of sustainable agricultural management policies, and formulation of strategies for adapting to climatic risks. To address the need for timely and accurate rice mapping, we developed a framework specifically designed for the diverse environmental conditions in Bangladesh. We utilized Sentinel-1 and Sentinel-2 time-series data to identify transplantation and peak seasons and employed the multi-Otsu automatic thresholding approach to map rice during the peak season (April-May). We also compared the performance of a random forest (RF) classifier with the multi-Otsu approach using two different data combinations: D1, which utilizes data from the transplantation and peak seasons (D1 RF) and D2, which utilizes data from the transplantation to the harvest seasons (D2 RF). Our results demonstrated that the multi-Otsu approach achieved an overall classification accuracy (OCA) ranging from 61.18% to 94.43% across all crop zones. The D2 RF showed the highest mean OCA (92.15%) among the fourteen crop zones, followed by D1 RF (89.47%) and multi-Otsu (85.27%). Although the multi-Otsu approach had relatively lower OCA, it proved effective in accurately mapping rice areas prior to harvest, eliminating the need for training samples that can be challenging to obtain during the growing season. In-season rice area maps generated through this framework are crucial for timely decision-making regarding adaptive management in response to climatic stresses and forecasting area-wide productivity. The scalability of our framework across space and time makes it particularly suitable for addressing field data scarcity challenges in countries like Bangladesh and offers the potential for future operationalization.


Assuntos
Oryza , Estações do Ano , Bangladesh , Ferramenta de Busca , Agricultura/métodos
2.
Cureus ; 16(3): e56870, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38659570

RESUMO

Pulmonary tuberculosis is an infection caused by Mycobacterium tuberculosis, which is an obligate aerobic microbe. Tuberculosis is a multisystemic disease that can attack the respiratory system, genitourinary system, central nervous system, gastrointestinal system, and the skeletal framework of the body. However, the most commonly affected system is the respiratory system (pulmonary tuberculosis). Tuberculosis is an ancient infection that affects millions of people every year, and even after adequate treatment, it is associated with significant morbidity and mortality, which can be attributed to reinfections, complications, extrapulmonary spread, and the long-term effects of tuberculosis on the lungs, leading to various restrictive and obstructive diseases. One of the most hazardous sequelae of pulmonary tuberculosis is the destroyed lung, which is predominately seen in the culminating stage of progressive disease or after reactivation of the disease. Here we present the case of a 46-year-old female patient who presented with complaints of breathlessness, cough with expectoration, and chest pain. With a history of recurrent tuberculosis infections and appropriate antituberculosis treatment for 30 years, the primary infection was recognized at 16 years of age. On examination, the patient was suspected to have developed fibrosis of the left lung, which, on radiological investigation, was confirmed to be a case of a destroyed left lung because of a recurrent tuberculosis infection. The patient was given symptomatic treatment along with broad-spectrum antibiotic therapy.

3.
Cureus ; 16(3): e55814, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38590501

RESUMO

The ocular analogue of a cerebral stroke is central retinal artery occlusion (CRAO), a medical emergency concerning the eyes. Most patients experience substantial acute vision loss with a visual acuity of 20/400 or worse, resulting in decreased quality of life (QoL) and decreased functional ability. An impending cerebral stroke and ischemic heart disease are also more likely. The four distinct clinical entities that make up CRAO are non-arteritic CRAO, transitory non-arteritic CRAO, non-arteritic CRAO with cilioretinal artery sparing, and arteritic CRAO. Depending on the CRAO type, clinical traits, visual results, and treatment all vary greatly. Contrary to current belief, there is a spontaneous improvement in the optical field and vision, mainly in the first week. The likelihood of instinctive development in optical acuity in the first seven days varies greatly. The pathogenesis, epidemiology, and medical features of CRAO will be described in this review, along with present and potential management future options.

4.
Ultrason Sonochem ; 99: 106566, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37659126

RESUMO

Focused high frequency ultrasound emulsification provides significant benefits such as enhanced stability, finer droplets, elevated focal pressure, lowered power usage, minimal surfactant usage and improved dispersion. Hence, in this study, the high frequency focused ultrasound emulsification of oil droplets in water was investigated through experiments and numerical modeling. The effect of transducer power (74-400 W), frequency (1.1 and 3.3 MHz), oil viscosity (10.6-512 mPas), interfacial tension (25-250 mN/m) and initial droplet radius (10-750 µm) on the emulsification process was assessed. In addition, the mechanism of droplet break-up was examined. The experiments showed that the acoustic pressure increased from 9.01 MPa to 26.24 MPa as the power was raised from 74 W to 400 W. At 74 W, the Weber number (We) at the surface and focal zone are 0.5 and 939.8, respectively. However, at 400 W, the We at the transducer surface and focal region reached 2.7 and 6451.8, respectively. Thus, bulb-like and weak catastrophic break up dominates the emulsification at 74 W. The catastrophic break up at 400 W is more vigorous because the ultrasound disruptive stress and We are higher. The time for the catastrophic dispersion of a single droplet at We = 939.8 and We = 6451.8 are 1.01 ms and 0.45 ms, respectively. The numerical model gives reasonable prediction of the trend and magnitude of the experimental acoustic pressure data. The surface and focal pressure amplitudes were estimated with errors of âˆ¼ 6.5% and âˆ¼ 10%, respectively. The predicted Reynolds number (Re) between 74 and 400 W were 8442 and 21364, respectively. The acoustic pressure at the focal region were âˆ¼ 26 MPa and âˆ¼ 69 MPa at frequencies of 1.1 MHz and 3.3 MHz, respectively. Moreover, the acoustic velocities were âˆ¼ 16 m/s and âˆ¼ 42 m/s at 1.1 MHz and 3.3 MHz, respectively. Hence, smaller droplets could be attained at higher frequency excitation under intense catastrophic modes. The Ohnesorge number (Oh) increased from 0.062 to 3.12 with the viscosity between 10.6 mPas and 530 mPas. However, the We remained constant at 856.14 for the studied range. Generally, higher critical We is required for the different breakup stages as the viscosity ratio is elevated. Moreover, the We increased from 25.68 to 1284.22 as the droplet radius was elevated from 15 to 750 µm. Larger droplets allow for higher possibility and intensity of breakup due to diminished viscous and interfacial resistance.

5.
Cureus ; 14(11): e31223, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36505141

RESUMO

Migraine is not only known to be one of the most common causes of a headache around the globe but is also the leading neurologic cause of disability worldwide. Migraine has significant social and economic effects. It not only hampers patients' quality of life but also hampers work, public conduct, and family life. Migraine is one of the leading causes of morbidity in the world, so effective management is critical. Currently, medical management is the mainstay remedial approach for migraine, but with time, non-pharmacological approaches, especially neuromodulation, are gaining popularity with a shred of solid backing evidence. Neuromodulation is the process in which specific devices are used to excite the central nervous system or peripheral nervous system with electric or magnetic, or any other form of energy to regulate the abnormal behavior of neural pathways that have occurred due to the disease process. Neuromodulation devices as approved by Food and Drug Administration include non-invasive Vagus nerve stimulators, single-pulse transcranial magnetic stimulators, and transcutaneous supraorbital neurostimulators. The purpose of this study is to summarize the information about the advances relating to neuromodulation concerning managing and preventing migraine. This Narrative review article is prepared after analyzing various research papers and publications on PubMed and Google Scholar. This article holds brief information on understanding neuromodulation, its mechanism, its implication in managing migraine, and its different modalities with their mechanism of action and contraindications. These neuromodulation techniques can certainly be used to deal with acute migraine attacks and inhibit their progression to chronic illness. Research is required on the application of neuromodulation in the early diagnosis of migraine, which is what we still lack as a whole medical fraternity.

6.
PLoS One ; 15(8): e0237324, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32813701

RESUMO

Flood inundation maps provide valuable information towards flood risk preparedness, management, communication, response, and mitigation at the time of disaster, and can be developed by harnessing the power of satellite imagery. In the present study, Sentinel-1 Synthetic Aperture RADAR (SAR) data and Otsu method were utilized to map flood inundation areas. Google Earth Engine (GEE) was used for implementing Otsu algorithm and processing Sentinel-1 SAR data. The results were assessed by (i) calculating a confusion matrix; (ii) comparing the submerge water areas of flooded (Aug 2018), non-flooded (Jan 2018) and previous year's flooded season (Aug 2016, Aug 2017), and (iii) analyzing historical rainfall patterns to understand the flood event. The overall accuracy for the Sentinel-1 SAR flood inundation maps of 9th and 21st August 2018 was observed as 94.3% and 94.1% respectively. The submerged area (region under water) classified significant flooding as compared to the non-flooded (January 2018) and previous year's same season (August 2015-2017) classified outputs. Summing up, observations from Sentinel-1 SAR data using Otsu algorithm in GEE can act as a powerful tool for mapping flood inundation areas at the time of disaster, and enhance existing efforts towards saving lives and livelihoods of communities, and safeguarding infrastructure and businesses.


Assuntos
Monitoramento Ambiental/métodos , Inundações/estatística & dados numéricos , Imagens de Satélites , Navegador , Monitoramento Ambiental/estatística & dados numéricos , Índia , Rios
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