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1.
Chemosphere ; 338: 139398, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37406939

RESUMO

A newly developed waste-to-energy system using a biomass combined energy system designed and taken into account for electricity generation, cooling, and freshwater production has been investigated and modeled in this project. The investigated system incorporates several different cycles, such as a biomass waste integrated gasifier-gas turbine cycle, a high-temperature fuel cell, a Rankine cycle, an absorption refrigeration system, and a flash distillation system for seawater desalination. The EES software is employed to perform a basic analysis of the system. They are then transferred to MATLAB software to optimize and evaluate the impact of operational factors. Artificial intelligence is employed to evaluate and model the EES software's analysis output for this purpose. By enhancing the flow rate of fuel from 4 to 6.5 kg/s, the cost rate and energy efficiency are reduced by 51% and increased by 6.5%, respectively. Furthermore, the maximum increment in exergetic efficiency takes place whenever the inlet temperature of the gas turbine rises. According to an analysis of three types of biomasses, Solid Waste possesses the maximum efficiency rate, work output, and expense. Rice Husk, in contrast, has the minimum efficiency, work output, and expense. Additionally, with the change in fuel discharge and gas turbine inlet temperature, the system behavior for all three types of biomasses will be nearly identical. The Pareto front optimization findings demonstrate that the best mode for system performance is an output power of 53,512 kW, a cost of 0.643 dollars per second, and a first law efficiency of 42%. This optimal value occurs for fuel discharge of 5.125 and the maximum inlet temperature for a gas turbine. The rates of water desalination and cooling in this condition are 18.818 kg/s and 2356 kW, respectively.


Assuntos
Inteligência Artificial , Água , Biomassa , Temperatura , Eletricidade
2.
PLoS One ; 18(4): e0283584, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37053221

RESUMO

Accurate product price forecasting is helpful for scientific decision-making and precise industrial planning. As a characteristic fruit that drives regional development, mango price prediction is of great significance to several economies. However, owing to the strong volatility of mango prices, forecasting is vulnerable to uncertainties and is very challenging. In this study, a deep-learning combination forecasting model based on a back-propagation (BP) long short-term memory (LSTM) neural network is proposed. Using daily mango price data from a large fruit wholesale trading center in China from January 2nd, 2014, to April 18th, 2022, mango price changes are learned and predicted to support the fruit industry. The results show that the root mean-square error, mean absolute percentage error, and the R2 determination coefficient of the BP-LSTM combination model are 0.0175, 0.14%, and 0.9998, respectively. The prediction results of the combined model are better than those of the separate BP and LSTM models. Furthermore, it best fits the actual price profile and has better generalizability.


Assuntos
Aprendizado Profundo , Mangifera , Redes Neurais de Computação , China , Memória de Longo Prazo , Previsões
3.
BMC Health Serv Res ; 17(1): 835, 2017 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-29258514

RESUMO

BACKGROUND: Social prescribing is targeted at isolated and lonely patients. Practitioners and patients jointly develop bespoke well-being plans to promote social integration and or social reactivation. Our aim was to investigate: whether a social prescribing service could be implemented in a general practice (GP) setting and to evaluate its effect on well-being and primary care resource use. METHODS: We used a mixed method evaluation approach using patient surveys with matched control groups and a qualitative interview study. The study was conducted in a mixed socio-economic, multi-ethnic, inner city London borough with socially isolated patients who frequently visited their GP. The intervention was implemented by 'social prescribing coordinators'. Outcomes of interest were psychological and social well-being and health care resource use. RESULTS: At 8 months follow-up there were no differences between patients referred to social prescribing and the controls for general health, depression, anxiety and 'positive and active engagement in life'. Social prescribing patients had high GP consultation rates, which fell in the year following referral. The qualitative study indicated that most patients had a positive experience with social prescribing but the service was not utilised to its full extent. CONCLUSION: Changes in general health and well-being following referral were very limited and comprehensive implementation was difficult to optimise. Although GP consultation rates fell, these may have reflected regression to the mean rather than changes related to the intervention. Whether social prescribing can contribute to the health of a nation for social and psychological wellbeing is still to be determined.


Assuntos
Medicina Geral , Atenção Primária à Saúde , Encaminhamento e Consulta , Meio Social , Isolamento Social , Adulto , Idoso , Feminino , Humanos , Londres , Masculino , Pessoa de Meia-Idade , Atenção Primária à Saúde/economia , Pesquisa Qualitativa , Encaminhamento e Consulta/estatística & dados numéricos , Projetos de Pesquisa , Determinantes Sociais da Saúde , Inquéritos e Questionários
4.
Indian J Hematol Blood Transfus ; 33(3): 380-388, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28824241

RESUMO

Hemophilic arthropathy (HA) can be diagnosed by a number of imaging studies. However, it is difficult with conventional radiography to find soft tissue structures around joints, and ultrasonography has limited effectiveness in evaluating internal bony structures. We attempt to determine whether a combination of ultrasonography for soft tissue around joints and conventional radiography for bony structures can be used as a cost-effective imaging tool for evaluating HA and whether it reflects the functional status of hemophilic patients. Thirty-six males (median age 16.5 years; severe 34, mild 2) with hemophilia were recruited. We evaluated the severity of HA using combined imaging score that consisted of modified Petterson X-ray score (mPXS) and the modified ultrasonographic score (mUS). Joint impairment was clinically assesses using the World Federation of Hemophilia-Physical Examination (WFH-PE) scale and the Hemophilic joint health score (HJHS). We assessed the Hemophilia activities list (HAL) for the functional level. We performed a comparative analysis between the combined imaging score and the joint impairment scores as well as the functional scores. The mean mUS was 4.97 ± 3.99 points, and the mean mPXS was 2.85 ± 2.91 points; the combined imaging score was 7.83 ± 6.31 points. The combined imaging score was significantly correlated with the HJHS (p = 0.006) and WFH-PE scores (p = 0.019) as well as the HAL score (p = 0.002). A combination of conventional radiological and ultrasongraphic study might ultimately impact the optimal evaluation of joint impairment and functional status in hemophilic patients.

5.
Med Sci Monit ; 23: 3585-3592, 2017 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-28735336

RESUMO

BACKGROUND The aim of this study was to investigate the feasibility of using acoustic radiation force impulse (ARFI) elastography, AST-to-platelet ratio index (APRI), and FIB-4 in assessing liver fibrosis and free portal pressure in patients with hepatitis B. MATERIAL AND METHODS We enrolled 126 patients with hepatitis B who underwent liver surgery at the General Surgery Department of the First Affiliated Hospital of Shihezi University Medical School from February 2013 to August 2015. Preoperatively, shear wave velocity (SWV) of the liver was measured with the Siemens S2000 ultrasound system to reflect liver stiffness. Serological markers were collected and fibrosis indices APRI and FIB-4 were calculated. Intraoperatively, liver tissues were harvested and free portal pressure (FPP) was measured. Postoperatively, fibrosis of liver tissues was pathologically staged. RESULTS The results of SWV, APRI, FIB-4, and FPP were all correlated with the degree of liver fibrosis (Spearman correlation coefficients: r=0.777, P<0.001; r=0.526, P<0.001; r=0.471, P<0.001; p<0.000; r=0.675, p<0.000). Receiver operating characteristic curve (ROC) analysis showed that the areas under the curve (AUC) of ARFI, APRI, and FIB-4 in diagnosing liver fibrosis were 0.830, 0.768, and 0.717, respectively, for stage F≥1; 0.861, 0.773, and 0.754, respectively, for stage F≥2; 0.941, 0.793, and 0.779, respectively, for stage F≥3; and 0.945, 0.783, and 0.754, respectively, for stage F=4. SWV, APRI, and FIB-4 were all correlated with FPP (Pearson correlation coefficients: 0.387, P<0.001; 0.446, P<0.001; 0.419, P<0.001). CONCLUSIONS ARFI, APRI, and FIB-4 can assess liver fibrosis in patients with hepatitis B when assessing the portal venous pressure. The difference in diagnostic efficacy between the 3 was not significant.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Cirrose Hepática/diagnóstico por imagem , Adulto , Idoso , Área Sob a Curva , Biomarcadores/sangue , Biópsia , Feminino , Hepatite B/diagnóstico por imagem , Hepatite B/fisiopatologia , Hepatite B Crônica/diagnóstico por imagem , Hepatite C Crônica/diagnóstico por imagem , Humanos , Fígado/diagnóstico por imagem , Cirrose Hepática/metabolismo , Masculino , Pessoa de Meia-Idade , Pressão na Veia Porta/fisiologia , Curva ROC , Ultrassonografia
6.
Food Chem ; 227: 369-375, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28274445

RESUMO

The purpose of this work was to develop an approach to produce size controlled starch nanoparticles (SNPs), via precipitation with high efficiency and low cost. High concentration starch aqueous pastes (up to 5wt.%) were treated by ultrasound. Viscosity measurements and size exclusion chromatography characterization revealed that, after 30min ultrasonic treatment, viscosity of the starch pastes decreased two orders of magnitude and the weight average molecular weight of the starch decreased from 8.4×107 to 2.7×106g/mol. Dynamic light scattering measurements and scanning electron microscopy observations showed that the SNPs prepared from the starch pastes with ultrasonic treatments were smaller (∼75nm) and more uniform. Moreover, SNPs could be obtained using less non-solvents. X-ray diffraction results indicated that effect of the ultrasonic treatment on crystalline structure of the SNPs was negligible. Ultrasound can be utilized to prepare smaller SNPs through nanoprecipitation with higher efficiency and lower cost.


Assuntos
Manipulação de Alimentos/métodos , Nanopartículas/química , Amido/química , Ultrassom/métodos , Precipitação Química , Manipulação de Alimentos/economia , Microscopia Eletrônica de Varredura , Peso Molecular , Tamanho da Partícula , Ultrassom/economia , Viscosidade , Difração de Raios X
7.
AJR Am J Roentgenol ; 208(4): 827-833, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28177647

RESUMO

OBJECTIVE: The objective of this study is to evaluate the diagnostic performance of 3D sampling perfection with application-optimized contrasts using different flip angle evolution (SPACE) sequences in the evaluation of ankle syndesmosis injuries, compared with that of conventional orthogonal MRI and oblique proton density-weighted turbo spin-echo (TSE) sequences performed with 3-T MRI. MATERIALS AND METHODS: This retrospective study included 98 patients with suspected ankle syndesmosis injuries who underwent both MRI and surgery. Fifty patients (mean [± SD] age, 34.5 ± 15.3 years) had acute injuries, and 48 patients (mean age, 28.5 ± 9.6 years) had chronic injuries. For both groups, the diagnostic performance of each MRI sequence with regard to syndesmosis injuries was evaluated. Arthroscopy findings were used as a reference standard to confirm diagnosis. RESULTS: No statistically significant differences in the sensitivity, specificity, accuracy, and AUC values were noted between images of the syndesmosis obtained using proton density-weighted TSE sequences and images of the syndesmosis obtained using 3D SPACE sequences (p > 0.05). Interobserver agreement regarding the diagnosis of both acute and chronic syndesmosis injuries was almost perfect for proton density-weighted TSE images (κ > 0.80) and was substantial for 3D SPACE images (κ > 0.75). Both methods of obtaining images of the syndesmosis had a diagnostic performance superior to that of conventional orthogonal MRI. CONCLUSION: The performance of 3D SPACE sequences is comparable to that of 2D proton density-weighted MR images for the diagnosis of acute and chronic syndesmosis injuries.


Assuntos
Traumatismos do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Posicionamento do Paciente/métodos , Adolescente , Adulto , Idoso , Anisotropia , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Processamento de Sinais Assistido por Computador , Adulto Jovem
8.
Clin Orthop Surg ; 6(3): 336-42, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25177461

RESUMO

BACKGROUND: This study was designed to perform conventional ultrasonography, magnetic resonance arthrography (MRA) and arthrosonography exams after rotator cuff repair to compare the results of conventional ultrasonography and arthrosonography with those of MRA as the gold standard. METHODS: We prospectively studied 42 consecutive patients (14 males, 28 females; average age, 59.4 years) who received arthroscopic rotator cuff repair due to full-thickness tears of the supraspinatus tendon from 2008 to 2010. The integrity assessment of the repaired rotator cuff was performed 6 months postoperatively using conventional ultrasonography, MRA, and arthrosonography. RESULTS: The diagnostic accuracy of the conventional ultrasonography compared to MRA was 78.6% and the McNemar test results were 0.016 in full-thickness tear and 0.077 in partial-thickness tear. The diagnostic accuracy of arthrosonography compared to MRA was 92.9% and the McNemar test results were 0.998 in full-thickness tear and 0.875 in partial-thickness tear. CONCLUSIONS: It was found that the integrity assessment of the repaired rotator cuff by ultrasonography must be guarded against and that arthrosonography is an effective alternative method in the postoperative integrity assessment. Also, an arthrosonography seems to be a suitable modality to replace the conventional ultrasonography.


Assuntos
Manguito Rotador/diagnóstico por imagem , Articulação do Ombro/diagnóstico por imagem , Traumatismos dos Tendões/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Artrografia , Artroscopia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Manguito Rotador/fisiopatologia , Manguito Rotador/cirurgia , Lesões do Manguito Rotador , Articulação do Ombro/fisiopatologia , Articulação do Ombro/cirurgia , Traumatismos dos Tendões/diagnóstico , Traumatismos dos Tendões/fisiopatologia , Traumatismos dos Tendões/cirurgia , Ultrassonografia , Cicatrização
9.
J Digit Imaging ; 15(4): 247-53, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12488966

RESUMO

The purpose of this study is to assess the association of implementation of PACS with the inpatient and outpatient revenue of a general hospital. The authors analyzed the in- and outpatient revenue data of all general hospitals (212) in South Korea obtained from the Korean National Health Insurance Corporation (KNHIC) during the period from 1996 through 1999 using the mixed model for repeated measure data. The following variables were used in the analysis: status of picture archiving and communication systems (PACS) implementation, population size, state of competition, inhabitant's income, hospital location, hospital size, whether a tertiary hospital, whether public or private, the effect of year. The revenues from both in- and outpatient departments were significantly higher one year after the introduction of PACS while controlling for the confounding variables. Although the causality needs to be clarified, the implementation of PACS was correlated significantly to the increased amount of inpatient and outpatient revenue.


Assuntos
Hospitais Gerais/economia , Serviço Hospitalar de Radiologia/economia , Sistemas de Informação em Radiologia/economia , Análise de Variância , Humanos , Coreia (Geográfico) , Análise de Regressão
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