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1.
Sci Rep ; 12(1): 16711, 2022 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-36202951

RESUMO

Drought is a natural disaster that causes much damage to the communities. Recently, water demand has been increasing sharply due to the population growth and the development process. By approaching the amount of water demand to the natural supplies, any decrease in the water supply may lead to a considerable negative socio-economic consequence. In this condition, the sense of drought prevails over the physical drought. Therefore, usual drought indices can not be used for characterizing and monitoring the drought in a basin. In this paper, multivariate standardized drought feeling index (MSDFI) is introduced which represents two dimensions of water management: (1) water supply in terms of precipitation and (2) water demand in terms of population. The MSDFI is calculated and its variation over time is compared to the standardized precipitation index (SPI). According to the results, MSDFI values in the early years were usually higher than SPI values and vice versa in the last years. This situation is highly correlated with the population trend in the basin. Thereafter, intensity of drought index (IDI) was defined as the difference between MSDFI and SPI to show the role of water demand in the drought feeling. Results show that IDI has an increasing trend in the populated areas, generally downstream of the basin, where population growth is high. In contrast, in the sparsely populated areas generally upstream of the basin where population growth is low and even negative due to migration, the IDI does not show any significant sense of drought.


Assuntos
Secas , Meteorologia , Meteorologia/métodos , Água , Abastecimento de Água
2.
Acta Med Iran ; 48(2): 130-2, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21133009

RESUMO

Aortobronchial fistula (ABF) is a rare and late complication of cardiac surgery. If untreated, mortality rate is approximately 100% secondary to exsanguinations haemoptysis. Early diagnosis and treatment are essential for successful management. Open surgical repair is associated with high morbidity and mortality rate, ranging from 25% to 41%. Endovascular treatments of ABF is a less invasive treatment modality and have become an important alternative to open surgical intervention in aortic pathologies. We present a case of ABF that successfully is managed by endovascular approach.


Assuntos
Fístula Brônquica/etiologia , Fístula Brônquica/terapia , Ponte de Artéria Coronária/efeitos adversos , Fístula Vascular/etiologia , Fístula Vascular/terapia , Fístula Brônquica/diagnóstico , Broncoscopia , Diagnóstico por Imagem , Humanos , Masculino , Pessoa de Meia-Idade , Fístula Vascular/diagnóstico
3.
Sci Rep ; 10(1): 20171, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-33214603

RESUMO

Reference evapotranspiration (ETo) is a basic element for hydrological designing and agricultural water resources management. The FAO56 recommended Penman-Monteith (FAO56-PM) formula recognized worldwide as the robust and standard model for calculating ETo. However, the use of the FAO56-PM model is restricted in some data-scarce regions like Bangladesh. Therefore, it is imperative to find an optimal alternative for estimating ETo against FAO56-PM model. This study comprehensively compared the performance of 13 empirical models (Hargreaves-Samani, HargreavesM1, Hargreaves M2, Berti, WMO, Abtew, Irmak 1, Irmak 2, Makkink, Priestley-Taylor, Jensen-Haise, Tabari and Turc) by using statistical criteria for 38-years dataset from 1980 to 2017 in Bangladesh. The radiation-based model proposed by Abtew (ETo,6) was selected as an optimal alternative in all the sub-regions and whole Bangladesh against FAO56-PM model owing to its high accuracy, reliability in outlining substantial spatiotemporal variations of ETo, with very well linearly correlation with the FAO56-PM and the least errors. The importance degree analysis of 13 models based on the random forest (RF) also depicted that Abtew (ETo,6) is the most reliable and robust model for ETo computation in different sub-regions. Validation of the optimal alternative produced the largest correlation coefficient of 0.989 between ETo,s and ETo,6 and confirmed that Abtew (ETo,6) is the best suitable method for ETo calculation in Bangladesh.

4.
Sci Total Environ ; 716: 137007, 2020 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-32036132

RESUMO

The purpose of the present paper is improving the accuracy of existing formulas for the longitudinal dispersion coefficient (LDC) prediction based on a novel and simple meta-heuristic optimization method called Whale Optimization Algorithm (WOA). Although several existing formulas calculate LDC in the rivers based on the hydraulic and hydrodynamic specifications, most of them have significant errors in confronting extensive field data. In this study, comprehensive field data, including the geometrical and hydraulic properties of different rivers in the world, were adopted to build a reliable model. Statistical error measures were used to evaluate and compare the results with other studies. Furthermore, the Subset Selection of Maximum Dissimilarity (SSMD) method was utilized for a reputable selection of data for training and testing the WOA model. Subset selection is a critical factor in artificial intelligence (AI) computations. Finally, an integrated model based on the SSMD method and WOA technique has been proposed to develop the high accuracy formulas for the prediction of LDC. According to the results, the developed formulas are competitive or superior to the previous formulas for LDC estimation. Results also indicated that the WOA algorithm could be applied to improve the performance of the predictive equations in other fields of studies by finding the optimum values of coefficients.

5.
Adv Pharm Bull ; 9(2): 255-261, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31380251

RESUMO

Purpose: Direct delivery of aminoglycosides to the lungs was under extensive evaluations during the last decades. Because of large particle size, low density and porous structure, large porous particles (LPPs) are versatile carriers for this purpose. In this study, poly (lactic-co-glycolic acid) (PLGA) LPPs encapsulating gentamicin sulfate were prepared and in vitro characteristics of their freeze-dried powder as a dry powder inhaler (DPI) were evaluated. Methods: To prepare PLGA LPPs, a double emulsification-solvent evaporation method was optimized and gentamicin sulfate was post-loaded in the LPPs. in vitro characteristics including morphological features, thermal behavior, aerodynamic profile and cumulative drug release were evaluated by the scanning electron microscope (SEM), differential scanning calorimetry (DSC), next-generation cascade impactor (NGI) and Franz diffusion cell respectively. Results: The obtained results revealed that the preparation method was capable to produce spherical large homogenous highly porous particles. 94% of gentamicin sulfate released from LPPs up to 30 minutes. Mass median aerodynamic diameter (MMAD) and fine particle fraction (FPF) were 4.9 µm and 39% respectively. Conclusion: In this study, dry powder formulation composed of PLGA LPPs encapsulating gentamicin sulfate showed a promising in vitro behavior as a pulmonary delivery carrier. Improvements on the aerodynamic behavior and in vivo evaluations recommended for further developments.

7.
Cell J ; 20(2): 267-277, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29633605

RESUMO

OBJECTIVES: The regenerative potential of bone marrow-derived mononuclear cells (MNCs) and CD133+ stem cells in the heart varies in terms of their pro-angiogenic effects. This phase II/III, multicenter and double-blind trial is designed to compare the functional effects of intramyocardial autologous transplantation of both cell types and placebo in patients with recent myocardial infarction (RMI) post-coronary artery bypass graft. MATERIALS AND METHODS: This was a phase II/III, randomized, double-blind, placebo-controlled trial COMPARE CPM-RMI (CD133, Placebo, MNCs - recent myocardial infarction) conducted in accordance with the Declaration of Helsinki that assessed the safety and efficacy of CD133 and MNCs compared to placebo in patients with RMI. We randomly assigned 77 eligible RMI patients selected from 5 hospitals to receive CD133+ cells, MNC, or a placebo. Patients underwent gated single photon emission computed tomography assessments at 6 and 18 months post-intramyocardial transplantation. We tested the normally distributed efficacy outcomes with a mixed analysis of variance model that used the entire data set of baseline and between-group comparisons as well as within subject (time) and group×time interaction terms. RESULTS: There were no related serious adverse events reported. The intramyocardial transplantation of both cell types increased left ventricular ejection fraction by 9% [95% confidence intervals (CI): 2.14% to 15.78%, P=0.01] and improved decreased systolic wall thickening by -3.7 (95% CI: -7.07 to -0.42, P=0.03). The CD133 group showed significantly decreased non-viable segments by 75% (P=0.001) compared to the placebo and 60% (P=0.01) compared to the MNC group. We observed this improvement at both the 6- and 18-month time points. CONCLUSIONS: Intramyocardial injections of CD133+ cells or MNCs appeared to be safe and efficient with superiority of CD133+ cells for patients with RMI. Although the sample size precluded a definitive statement about clinical outcomes, these results have provided the basis for larger studies to confirm definitive evidence about the efficacy of these cell types (Registration Number: NCT01167751).

8.
Arch Iran Med ; 10(4): 543-5, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17903065

RESUMO

Surgical closure of ventricular septal defect is safe, however, the inherent risks associated with cardiopulmonary bypass and the potential early and late postsurgical complications including complete heart block, arrhythmias, postpericardiotomy syndrome, and rare deaths have led physicians to prefer transcatheter occlusion technique for closure of such defects. The use of Amplatzer muscular ventricular septal defect occluder is safe and associated with a higher success rate than other previously used devices. For the first time in Iran, we report an 18-year-old patient with ventricular septal defect who was successfully treated using the Amplatzer ventricular septal defect occluder.


Assuntos
Procedimentos Cirúrgicos Cardíacos/instrumentação , Procedimentos Cirúrgicos Cardíacos/métodos , Comunicação Interventricular/terapia , Adolescente , Humanos , Masculino
9.
J Tehran Heart Cent ; 6(2): 79-84, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-23074610

RESUMO

BACKGROUND: The transcatheter closure of the atrial septal defect (ASD) has become an alternative technique to surgical procedures. The aim of this study was to assess the immediate, short, and intermediate-term results of the transcatheter closure of the secundum ASD with the Amplatzer Septal Occluder (ASO) in adult Iranian patients. METHODS: Between December 2004 and July 2008, the transcatheter closure of the ASD using the ASO was attempted in 58 consecutive, adult patients. The mean age of the patients was 37.1 ± 12.7 years (range = 19 - 75 years). All the procedures were performed under local anesthesia with transthoracic or transesophageal echocardiography and fluoroscopic guidance. The stretched diameter of the ASD was determined with a balloon sizing catheter, and device selection was based on and matched to the stretched diameter of the septal defect. Transthoracic echocardiography was performed immediately after the release of the device and before discharge. Further follow-up at one month, six months, and yearly thereafter included physical examination, electrocardiography, and transthoracic echocardiography. RESULTS: The mean ASD diameter, as measured by esophageal echocardiography, was 24.8 ± 5.4 mm (range = 13 - 34 mm). The mean stretched diameter, as measured by the balloon catheter, was 27.1 ± 6.4 mm (range = 12.5 - 39 mm). Deployment of the ASO was successful in 52 (89.6%) patients and failed in 6 (10.4%). Four patients experienced severe complications, 1 had tamponade requiring drainage, 2 had device embolization to the left atrium and right ventricular outflow tract, and 1 had late wire fracture (surgical removal and repair of the ASD). The position of two large devices (34 mm and 36 mm) was considered unsuitable and unstable after implantation and resulted in the removal of these devices. Minor complications included transient complete atrioventricular block in 1 patient, paroxysmal supra tachycardia in 3 patients, atrial flutter in 1 patient, and angina pectoris with transient ST elevation in 2 patients. The mean follow-up period was 32.5 ± 18.5 months. Echocardiography at 24 hours, 1 month, 6 months, and 12 months after the procedure showed residual shunts in 11 (21%), 3 (5.8%), 2 (3.8%), and 2 (3.8%) patients, respectively. At follow-up (12.8 months to 48.5 months, mean ± SD = 32.5 ± 18.5 months), complete closure was documented in 50 (96.2 %) of the 52 cases. At the end of the follow-up, 2 (3.8%) patients had residual shunts: The shunt was moderate in 1 (1.9%) patient and small in the other (1.9%). The overall success rate of the transcatheter closure of the ASD was 86% (50 of 58 cases). CONCLUSION: The transcatheter closure of the secundum ASD in our adult patient population using the ASO was associated with high degrees of success, minimal procedural complication rates, and excellent short and midterm results. The use of this device, however, requires thorough attention in that the procedure may be ineffective or the device may embolize. Further experience and long-term follow-up are required before a widespread clinical use can be recommended.

10.
J Interv Cardiol ; 18(3): 181-3, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15966922

RESUMO

In this study we evaluated the development of migraine after percutaneous closure of atrial septal defect. An abrupt and excruciating form of migraine developed shortly after shunt closure in 5 of 13 consecutive patients undergoing this procedure. A dramatic relief of pain was achieved almost instantaneously after administration of 300 mg of clopidogrel.


Assuntos
Comunicação Interatrial/cirurgia , Enxaqueca sem Aura/etiologia , Procedimentos Cirúrgicos Minimamente Invasivos/efeitos adversos , Adulto , Cateterismo Cardíaco , Clopidogrel , Ecocardiografia Transesofagiana , Feminino , Seguimentos , Comunicação Interatrial/diagnóstico por imagem , Humanos , Masculino , Enxaqueca sem Aura/tratamento farmacológico , Inibidores da Agregação Plaquetária/uso terapêutico , Complicações Pós-Operatórias , Índice de Gravidade de Doença , Ticlopidina/análogos & derivados , Ticlopidina/uso terapêutico , Fatores de Tempo , Resultado do Tratamento
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