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1.
Transfus Clin Biol ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38604406

RESUMO

BACKGROUND AND OBJECTIVES: The process of selecting blood donors is crucial for keeping the health of donors and ensuring the safety of the blood supply. However, it may create unpleasant feeling in those who are deferred. In this study, we aim to explore the return rates of Iranian deferred donors in comparison with eligible donors. MATERIALS AND METHODS: The study included all whole blood donors referred between March 2017 and March 2018, who experienced temporary deferral for any reason. Donors who successfully donated blood during this period were also part of the study. Participants were followed up until their next donation attempt, spanning 4.8 years after initial inclusion. Then odds of return and median return time for both deferred and eligible donors were calculated. RESULTS: From 993,824 volunteers, 733,153 (73.77%) were eligible and 192,332 (19.35%) temporary deferred. The return rate in the eligible and deferred donors was 74.77% vs. 51.77%, respectively (OR:2.78; 99%CI: 2.71-2.81). Odds of return among deferred regular (OR = 7.02, 99%CI:6.64-7.42), men (OR: 2.57, 99%CI:2.45-2.69), and over 45 years (OR: 1.15, 99% CI: 1.09-1.20), was higher than first-time, women, and younger donors. The median return time for eligible and deferred donors was 315 (99%CI: 313-316) and 1,467(99%CI: 1,412-1,524) days, respectively. CONCLUSION: This study revealed the negative effect of deferral on the return rate, that led to a 23% reduction in the return of deferred donors. Avoiding unnecessary deferral through adherence to the standard operating procedure of donor selection and effective counselling which clarifies the purpose of deferral and encourages them to return after the deferral period ends are recommended.

2.
Adv Mater ; 35(42): e2302826, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37562445

RESUMO

Modern materials science has witnessed the era of advanced fabrication methods to engineer functionality from the nano- to macroscales. Versatile fabrication and additive manufacturing methods are developed, but the ability to design a material for a given application is still limited. Here, a novel strategy that enables target-oriented manufacturing of ultra-lightweight aerogels with on-demand characteristics is introduced. The process relies on controllable liquid templating through interfacial complexation to generate tunable, stimuli-responsive 3D-structured (multiphase) filamentous liquid templates. The methodology involves nanoscale chemistry and microscale assembly of nanoparticles (NPs) at liquid-liquid interfaces to produce hierarchical macroscopic aerogels featuring multiscale porosity, ultralow density (3.05-3.41 mg cm-3 ), and high compressibility (90%) combined with elastic resilience and instant shape recovery. The challenges are overcome facing ultra-lightweight aerogels, including poor mechanical integrity and the inability to form predefined 3D constructs with on-demand functionality, for a multitude of applications. The controllable nature of the coined methodology enables tunable electromagnetic interference shielding with high specific shielding effectiveness (39 893 dB cm2 g-1 ), and one of the highest-ever reported oil-absorption capacities (487 times the initial weight of aerogel for chloroform), to be obtained. These properties originate from the engineerable nature of liquid templating, pushing the boundaries of lightweight materials to systematic function design and applications.

3.
Sci Total Environ ; 811: 152347, 2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-34921888

RESUMO

Understanding of how anthropogenic droughts occur in socio-hydrological systems is critical in studying resilience of these systems. This is especially relevant when a "lock-in" toward watershed desiccation occurs as an emergent outcome of coupling among social dynamics and surface and underground water processes. How the various processes collectively fit together to reinforce such a lock-in and what may be a critical or ignored feedback worsening the state of the socio-hydrological systems remains poorly understood. Here we tackle this gap by focusing on the case of Lake Urmia in Iran, a saline lake that faces the same fate as that of Aral Sea due to over-extraction of water sources that feed the lake. We develop an integrative, system-level understanding of how various anthropogenic, surface and underground environmental processes collectively generate the water scarcity and soil salinization issues in the study case. To this end, we investigate a paradoxical phenomenon wherein the increase of soil salinity has not noticeably affected the level of vegetation cover in Lake Urmia Basin. The outcome of our analysis may provide useful insights for informing policymakers how to cope with drought and water scarcity issues in many fragile saline lakes around the world that are currently under threat by overexploitation.


Assuntos
Água Subterrânea , Lagos , Dessecação , Secas , Monitoramento Ambiental , Hidrologia
4.
Transfus Apher Sci ; 60(4): 103129, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33879420

RESUMO

Call back as a procedure to report post donation symptoms or illness by donors has been established since 2009 in Iranian Blood Transfusion Organization (IBTO). During the first phase of COVID-19 outbreak, all blood donors were requested to report any respiratory infection symptoms after donation. The study investigated the callback data of COVID-19 in Tehran Blood Center during the first 3 months of the outbreak in Iran. The purpose of this study was to estimate the frequency of post donation COVID-19 related call back reports and determine its implications for blood donors and patients. A telephone interview was conducted with donors who had reported COVID-19 symptoms. Some questions were asked to evaluate donor's health at the time of blood donation. The donors categorized into three groups: laboratory-confirmed, suspected, and COVID-19 irrelevant based on their answers. In cases that the blood component obtained from a laboratory-confirmed donor had been released, the hospital was notified and asked to follow up the recipient for COVID-19. The results showed 30 donors (0.08 %) had callback related to COVID-19 and 76.63 % of the obtained component was disposed. The results also showed that only one donor had a laboratory-confirmed result with the RBC unit processed from her whole blood released for transfusion. The RBC unit recipient did not show any signs or symptoms of infection during a 46-day follow-up. Concluded that callback system was effective to remove most of the components obtained from the donors who reported to be COVID-19 suspected or confirmed. Moreover, the result did not support virus transmission through blood transfusion.


Assuntos
Doadores de Sangue , Segurança do Sangue , Infecções Transmitidas por Sangue/prevenção & controle , COVID-19/prevenção & controle , Seleção do Doador , Pandemias , SARS-CoV-2 , Reação Transfusional/prevenção & controle , Adulto , Idoso , Transfusão de Componentes Sanguíneos/efeitos adversos , Transfusão de Componentes Sanguíneos/estatística & dados numéricos , COVID-19/sangue , COVID-19/diagnóstico , COVID-19/transmissão , Teste de Ácido Nucleico para COVID-19 , Transfusão de Eritrócitos/efeitos adversos , Feminino , Seguimentos , Humanos , Recém-Nascido , Entrevistas como Assunto , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Estenose da Valva Pulmonar/cirurgia , Avaliação de Sintomas , Adulto Jovem
5.
Environ Sci Pollut Res Int ; 26(8): 8325-8339, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30706265

RESUMO

Developing a reliable groundwater vulnerability and contamination risk map is very important for groundwater management and protection. This study aims to compare various modified DRASTIC vulnerability frameworks based on rate calibration using the Wilcoxon rank-sum test (WRST), frequency ratio (FR) and weight optimization using the correlation coefficient (CC), the analytic hierarchy process (AHP), and genetic algorithms (GA), as well as to introduce, for the first time, an aggregated approach based on a bagging ensemble to develop a combined modified DRASTIC model. This research was conducted in the Khoy plain, NW Iran. To develop a typical DRASTIC map, seven DRASTIC data layers were generated, weighted, and then overlaid in ArcGIS. The nitrate (NO3) concentrations at 54 sites in the study area were used to validate the models by calculating the correlation coefficient (r) between the vulnerability/risk indices and NO3 concentrations. The calculated r value for the typical DRASTIC was 0.12. A sensitivity analysis reveals that the impact of the vadose zone and conductivity parameters with mean variation indices of 22.2 and 7.5%, respectively, have the highest and lowest influence on aquifer vulnerability. The r values increased for all the optimized frameworks. The results show that the WRST and GA methods are the most effective methods for calibration and optimization of DRASTIC rates and weights, with the WRST-GA-DRASTIC model obtaining an r value of 0.64. A bagging ensemble model was employed to combine the advantages of each standalone model. The bagging ensemble model yields an r value of 0.67. The ensemble model has the potential to increase the r value further than both the standalone optimized frameworks and the typical DRASTIC approach. In terms of spatial distribution class area (%), the bagging ensemble-DRASTIC model demonstrates that the moderate and low contamination risk classes with 16.4 and 23.1% of the total area cover the lowest and highest parts of the plain.


Assuntos
Água Subterrânea/análise , Hidrologia/métodos , Poluição da Água/análise , Algoritmos , Calibragem , Irã (Geográfico) , Modelos Estatísticos , Modelos Teóricos , Nitratos/análise
6.
Environ Geochem Health ; 41(2): 981-1002, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30269268

RESUMO

The objectives of this study were to measure some trace element concentrations in the groundwater of the Khoy area in northwestern Iran, understand their potential origins using multivariate statistical approaches (correlation analysis, cluster analysis and factor analysis), and evaluate their non-carcinogenic human health risks to local residents through drinking water intake. The trace element status of the groundwater and the associated health risks in the study area have not previously been reported. Groundwater water samples were collected from 54 water sources in July 2017 in the study area. Samples were measured for EC, pH, major and minor elements and some trace elements (Fe, Mn, Al, Zn, Cr, Pb, Cd, Co, Ni and As). The levels of EC, F, Cd, Pb, Zn, As and all the major ions except K exceeded permissible levels for drinking water. Multivariate analysis showed that the quality of groundwater was mainly controlled by geogenic factors followed by anthropogenic impacts. Health risk assessment results indicated that Cr and As in the groundwater, with hazard quotient values of 0.0001 and 11.55, respectively, had the lowest and highest impacts of non-carcinogenic risk to adults and children in the area. The high-risk samples were mainly situated in the northeast and southwest of the Khoy plain where the groundwater was saline. The health risk associated with water consumption from the unconfined aquifer was higher than that from the confined aquifer in the study area. Special attention should be paid to groundwater management in the high-risk areas to control factors (e.g., EC, pH and redox) that stimulate the release of trace elements into groundwater.


Assuntos
Água Subterrânea/análise , Metais/análise , Medição de Risco/métodos , Poluentes Químicos da Água/análise , Adulto , Carcinógenos/toxicidade , Criança , Análise por Conglomerados , Monitoramento Ambiental/métodos , Água Subterrânea/química , Humanos , Irã (Geográfico) , Metais/toxicidade , Análise Multivariada , Poluentes Químicos da Água/toxicidade
7.
Iran J Public Health ; 47(11): 1749-1755, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30581793

RESUMO

BACKGROUND: Alteration of environmental factors and air pollution affects the trend of allergic diseases especially in cities such as Tehran. This study aimed to determine the prevalence of allergic rhinitis, conjunctivitis, atopic dermatitis and asthma among adults in the capital city of Iran. METHODS: This cross-sectional study was performed between 2013 and 2016 in Tehran, Iran. The participants were adults between 18 and 45 yr of age. A specific questionnaire including demographic data and clinical symptoms was filled out by a trained interviewer. The diagnosis of allergic diseases was performed based on standard questionnaires and criteria. RESULTS: The prevalence of allergic rhinitis, conjunctivitis, asthma and atopic dermatitis were 28.3%, 15.9%, 7.6% and 3.9%, respectively. Allergic rhinitis and conjunctivitis together were reported in 12.3% of the participants. Among patients with asthma, 47.4% had AR. Additionally, 25.7% of atopic dermatitis subjects were reported to have asthma. The subjects with at least one of these allergic diseases were 36.3%. Women showed a higher prevalence of allergic symptoms than men. There was a significant relationship between allergic symptoms and family history of atopic diseases. CONCLUSION: The most common allergic disease was allergic rhinitis. Regarding the comorbidity of asthma and allergic rhinitis, paying more attention to controlling these allergic diseases is deemed necessary.

8.
Nanotechnology ; 26(5): 055601, 2015 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-25573923

RESUMO

Functional colloidal materials were prepared by design through the self-assembly of nanoparticles (NPs) on the surfaces of polystyrene (PS) spheres with control over NP surface coverage, NP-to-NP spacing, and NP composition. The ability to control and fine tune the coating was extended to the first demonstration of the co-assembly of NPs of dissimilar composition onto the same PS sphere, forming a multi-component coating. A broad range of NP decorated PS (PS@NPs) spheres were prepared with uniform coatings attributed to electrostatic and hydrogen bonding interactions between stabilizing groups on the NPs and the functionalized surfaces of the PS spheres. This versatile two-step method provides more fine control than methods previously demonstrated in the literature. These decorated PS spheres are of interest for a number of applications, such as catalytic reactions where the PS spheres provide a support for the dispersion, stabilization, and recovery of NP catalysts. The catalytic properties of these PS@NPs spheres were assessed by studying the catalytic degradation of azo dyes, an environmental contaminant detrimental to eye health. The PS@NPs spheres were used in multiple, sequential catalytic reactions while largely retaining the NP coating.


Assuntos
Nanopartículas/química , Poliestirenos , Compostos Azo/metabolismo , Catálise , Nanotecnologia
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