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1.
J Environ Manage ; 359: 120761, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38703641

RESUMO

Plants are arguably the most visible components of stormwater bioretention basins and play key roles in stabilizing soils and removing water through transpiration. In regions with cold winters, bioretention basins along roadways can receive considerable quantities of deicing salt, much of which migrates out of the systems prior to the onset of plant growth but the rest remains in the soil. The resulting effects on plants presumably vary with time (due to annual weather patterns), space (because stormwater exposure is location-dependent), and biology (because plant taxa differ in their salt tolerance). The goal of this study was to investigate the magnitude of deicing salt's effects on bioretention plants and how it varies with spatial, temporal, and biological factors. The study took place in a set of five bioretention basins in Philadelphia, USA that receive runoff from a major highway. Over a five-year period, the electrical conductivity (EC) of influent stormwater frequently exceeded 1 mS cm-1 in winter, and occasionally surpassed that of seawater (∼50 mS cm-1). In both of the years when soil EC was measured as well, it remained elevated through all spring months, especially near basin inlets and centers. Mortality of nine plant taxa ranged widely after three years (0-90%), with rankings largely corresponding to salt tolerances. Moreover, leaf areas and/or crown volumes were strongly reduced in proportion to stormwater exposure in seven of these taxa. In the three taxa evaluated for tissue concentrations of 14 potentially toxic elements (Hemerocallis 'Happy Returns', Iris 'Caesar's Brother', and Cornus sericea 'Cardinal'), only sodium consistently exceeded the toxicity limit for salt intolerant plants (500 mg kg-1). However, exceedance of the sodium toxicity limit was associated with plants' topographic positions, with median concentrations greatest in the bottom of basins and least on basin rims. This study demonstrates that deicing salts can have detrimental effects on plants in bioretention basins, with the strongest effects likely to occur in years with the greatest snowfall (and therefore deicing salt use), in portions of basins with greatest stormwater exposure (typically around inlets and centers), and in plants with minimal salinity tolerance. Our results therefore underscore the value of installing salt-tolerant taxa in basins likely to experience any frequency of deicing salt exposure.


Assuntos
Solo , Solo/química , Plantas/efeitos dos fármacos
2.
Environ Monit Assess ; 195(7): 860, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37335439

RESUMO

The soil freeze-thaw process is a transition phase of soil water in cold areas that influences the soil's hydrological behavior. However, dynamic phenomena and corresponding consequences have yet to be studied adequately. Therefore, the present study was planned to comparatively analyze the effects of a freezing-thawing cycle on the hydrologic behaviors of loess soil from northeast Iran. Small-size (0.5 × 0.50 m) erosion plots were subjected to a freezing-thawing cycle under governing conditions of the region of the origin soil. The plots were subjected to a freezing-thawing treatment by inducing cold air until the temperature declined to below - 20 °C and lasted for 3 days using a cooling compartment system and then were kept in the laboratory with an ambient temperature of above 10 °C for 2 days. The treated plots and untreated plots were then exposed to a simulated rainfall with an intensity of 72 mm h-1 and 0.5 h duration while they were placed on a slope of 20%. The results indicated that the hybrid processes of freezing-thawing and splash and inter-rill erosions significantly increased runoff generation and soil loss. The time to runoff, runoff volume, and soil loss were 1.65 times less and 1.38 and 2.90 times more, respectively, compared to those reported for the control treatment with significant differences (p < 0.006). The performance of ice lenses, freezing fronts, and the creation of near-saturation moisture after completing the cycle were identified as the most critical factors affecting the different soil behaviors under the frozen-thawed cycle.


Assuntos
Monitoramento Ambiental , Solo , Congelamento , Monitoramento Ambiental/métodos , Temperatura Baixa , Temperatura
3.
BMC Health Serv Res ; 20(1): 14, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31902368

RESUMO

BACKGROUND: Nowadays, a growing literature reveals how patients use informal payments to seek either better treatment or additional services, but little systematic review has been accomplished for synthesizing the main factors. The purpose of this study was to analyze the content of literatures to demonstrate the factors for informal patient payments. METHODS: In this systematic review study, PubMed, Web of Science, Wiley Online Library, Science Direct, Ovid, Scopus, and Iranian databases were investigated without time limitation for eligible English and Persian studies. Achieved data were analyzed using content analysis approach and MAXQDA 10 software. RESULTS: Themes related to informal payments in external context of health system were demographic features of health service consumers, patient's personality features and social & cultural backgrounds of the community. Health system challenges' themes were about stewardship weakness, and sustainable financing and social protection weakness. These were followed by human resources' organizational behavior challenges, drugs, medical products, and services delivery provision process challenges and finally change management weakness for reducing and dealing with IPs. CONCLUSION: It appears that improving the quality of health care services and accurate monitoring of delivery processes, along with performing some strategies for regulating payroll and medical tariffs, strict rules and regulations and improving health staff motivation, would be effective ways against informal payments. Improving the health insurance contribution, promoting transparency & accountability in health system especially in financing, identify precise control mechanism, using empower patient/public related approach, modifying community perception, reinforcing social resistance to unofficial payments and rebuilt lost social capital in health care are some of the other recommendations in this field. To practice these strategies, a comprehensive and systemic vision and approach is needed, however, the key point is that before applying any strategy the impact of this strategy on access, efficiency, equity, and other health systems' goals and policies should be investigated due to the consideration.


Assuntos
Financiamento Pessoal/estatística & dados numéricos , Humanos
4.
J AOAC Int ; 98(5): 1417-22, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26525261

RESUMO

A new method was applied to produce modified nanoporous silica as a novel sorbent for Pb(II) ion SPE from industrial wastewater samples. In this modified method, the produced nanoporous silica has a higher functional group loading, which leads to a higher preconcentration factor as well as a lower LOD. This modified nanoporous silica was used for preconcentration prior to subsequent determination of Pb(II) ions by flame atomic absorption spectrometry. Various parameters such as the eluent, pH of the sample solution, and flow rate were optimized during this work. Also, the effect of a variety of ions on preconcentration and recovery of Pb(II) ions was investigated. The LOD, defined as five times the SD of the blank, was determined to be lower than 0.1 mg/L with an RSD of <2%. The accuracy of the method was established by analyzing standard reference materials with certified Pb concentrations. Finally, the established method was successfully applied for determination of the Pb(II) ion concentration in industrial wastewater samples.


Assuntos
Imidazóis/química , Chumbo/isolamento & purificação , Dióxido de Silício/química , Extração em Fase Sólida/métodos , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Cátions Bivalentes , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Nanoestruturas , Porosidade , Padrões de Referência , Espectrofotometria Atômica/métodos , Águas Residuárias/química
5.
J Med Signals Sens ; 13(3): 208-216, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37622039

RESUMO

Background: Computed tomography (CT) of the brain is associated with radiation exposure to the lens of the eyes. Therefore, it is necessary to optimize scan settings to keep radiation exposure as low as reasonably achievable without compromising diagnostic image information. The aim of this study was to compare the effectiveness of the five practical techniques for lowering eye radiation exposure and their effects on diagnostic image quality in pediatric brain CT. Methods: The following scan protocols were performed: reference scan, 0.06-mm Pbeq bismuth shield, 30% globally lowering tube current (GLTC), reducing tube voltage (RTV) from 120 to 90 kVp, gantry tilting, and combination of gantry tilting with bismuth shielding. Radiation measurements were performed using thermoluminescence dosimeters. Objective and subjective image quality was evaluated. Results: All strategies significantly reduced eye dose, and increased the posterior fossa artifact index and the temporal lobe artifact index, relative to the reference scan. GLTC and RTV increased image noise, leading to a decrease signal-to-noise ratio and contrast-to-noise ratio. Except for bismuth shielding, subjective image quality was relatively the same as the reference scan. Conclusions: Gantry tilting may be the most effective method for reducing eye radiation exposure in pediatric brain CT. When the scanner does not support gantry tilting, GLTC might be an alternative.

6.
JOP ; 12(5): 438-44, 2011 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-21904068

RESUMO

CONTEXT: Pancreas cancer can potentially be cured by resection, but the role of adjuvant chemotherapy and/or chemoradiation has been controversial. OBJECTIVES: To better define clinicopathological factors that may serve as predictive and/or prognostic variables. PATIENTS: Between 1984 and 2006, we retrospectively analyzed 91 patients with pancreas cancer treated with pancreaticoduodenectomy or total pancreatectomy followed by adjuvant 5-fluorouracil-based chemoradiation at the University of Pennsylvania. Final pathological coding including margin status was confirmed by a pathologist. INTERVENTIONS: Patients were treated with 48.6 to 63.0 Gy, and 96.7% completed their prescribed radiation dose. MAIN OUTCOME MEASURES: The prognostic significance of demographic factors, stage, year of surgery, tumor location, grade, resection status, and number of positive lymph nodes on overall survival were examined. RESULTS: With a median follow-up of 6.5 years, the overall median survival was 2.3 years (95% CI 1.5-3.2 years), and the 5-year overall survival was 28.9%. In multivariate analysis, completeness of resection (P<0.001), fewer number of positive lymph nodes (0 vs. 1-2 vs. 3 or more) (P=0.004), and age less than, or equal to, 60 years (P=0.006) were all independently associated with improved overall survival. The overall survival reported in this study compares favorably with the results of other single-institution studies and with the RTOG 97-04 trial. CONCLUSIONS: Adjuvant 5-FU-based chemoradiation following radical pancreatectomy can be delivered safely and results in comparatively good overall survival. The results of this analysis underscore the importance of resection status, number of involved lymph nodes and patient age as prognostic characteristics. These factors may be considered stratification variables for future post-pancreatectomy adjuvant therapy trials.


Assuntos
Adenocarcinoma/mortalidade , Adenocarcinoma/terapia , Quimiorradioterapia Adjuvante , Pancreatectomia/estatística & dados numéricos , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/terapia , Adenocarcinoma/diagnóstico , Adenocarcinoma/patologia , Fatores Etários , Idoso , Terapia Combinada , Feminino , Humanos , Linfonodos/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patologia , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida
7.
Mol Cancer Res ; 19(3): 403-413, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33272936

RESUMO

Muscle-invasive bladder cancer (MIBC) frequently harbors mutations in the CDKN1A gene, which encodes the tumor suppressor protein p21, with the majority of alterations truncating the peptide. The effect of these mutations is poorly understood. We hypothesized that after DNA-damaging events, cells deficient in p21 would be unable to halt the cell cycle and efficiently repair DNA damage, thus proceeding down the apoptotic pathway. We used synthetic CRISPR guide RNAs to ablate the whole peptide (sg12, targeting the 12th amino acid) or the C-terminal proliferating cell nuclear antigen (PCNA)-binding domain (sg109) to mimic different p21-truncating mutations compared with a negative control (sgGFP) in bladder cancer cell lines. Loss of detectable p21 and a stable truncated p21 peptide were identified in sg12 and sg109 single-cell clones, respectively. We found that p21-deficient cells (sg12) were sensitized to cisplatin, while cells harboring distally truncated p21 (sg12 clones) demonstrated enhanced cisplatin resistance. p21-deficient sg12 clones demonstrated less repair of DNA-platinum adducts and increased γ-H2AX foci after cisplatin exposure, suggesting there was persistent DNA damage after p21 loss. p21-deficient sg12 clones were also unable to prevent the activation of CDK1 after DNA damage, and therefore, continued through the cell cycle, resulting in replication fork collapse, potentially explaining the observed cisplatin sensitization. sg109 clones were neither unable to sequester PCNA nor localize p21 to the nucleus after DNA damage, potentially explaining the chemoresistant phenotype. Our findings suggest that different CDKN1A truncations have different and perhaps disparate biology, and that there may be a duality of effect on cisplatin sensitivity depending on mutation context. IMPLICATIONS: Some truncating CDKN1A mutations generate a retained peptide that may have neomorphic functions and affect cisplatin sensitivity in patients with bladder cancer.


Assuntos
Cisplatino/uso terapêutico , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Neoplasias da Bexiga Urinária/tratamento farmacológico , Cisplatino/farmacologia , Humanos , Mutação
8.
J Contam Hydrol ; 234: 103685, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32799044

RESUMO

Stormwater management practices (SMPs) rely on infiltration and adsorption capabilities of soil and vegetative cover to mitigate the harmful impacts of contaminants in stormwater runoff, including potentially toxic elements (PTEs). Under chemical equilibrium conditions, the soil-water distribution coefficient (Kd) quantifies the relationship between the solid and aqueous phase PTE concentrations, and thus the PTE removal efficiency and mobility through the SMP soil layers during the infiltration process. The SMP loading ratio (LR), the ratio of the drainage area to the SMP infiltration area, combined with runoff concentration determines SMP mass loading and is also expected to impact PTE transport. In this study, a simulation model was developed to investigate PTE breakthrough and build-up in SMP media, considering the impacts of Kd and LR. Eight PTEs were simulated (Cl-, Cr, Fe, Zn, Cu, As, Cd, and Pb), and Cl- was the only PTE that showed high mobility and reached the groundwater table (e.g., ~ 1 year for breakthrough). Conversely, other PTEs were effectively immobilized in the top ~60 cm of soil for a simulated lifespan of 20 years. Soil and porewater contaminant indices, as indicators of SMP lifespan, were estimated based on the ratio of PTE porewater and soil concentrations after 20 years to published standards, suggesting the following order of environmental significance (most concern to least): Cl- > Cr > As > Pb > Fe > Cu > Cd > Zn. After 20 years of simulated use, only Cl- pore water concentrations at the groundwater table exceeded regulatory values, with porewater contamination index values of 4 to 7.5. Chloride also exceeded the surficial media soil contamination index, as did As and Cr, though these exceedences were largely associated with media background concentrations. Generally, higher LR and Kd contributed to higher accumulation of PTEs in top layers; however, simulations showed that the combination of low LR and high Kd may result in lower PTE accumulation in the media, such that the PTE concentration in soil may decrease in deeper layers. In these scenarios, a notable fraction of PTE load was adsorbed on top layers and considerably lower PTE concentrations reached the lower layers. Sensitivity analysis revealed that dispersion, infiltration rate, and kinetically-limited sorption did not impact the PTE accumulation and mobility to a practical extent. The results from this simulation may be adapted to various environmental conditions to enhance the design and maintenance of SMPs.


Assuntos
Metais Pesados , Poluentes do Solo , Monitoramento Ambiental , Metais Pesados/análise , Chuva , Solo , Poluentes do Solo/análise
9.
Sci Total Environ ; 646: 1554-1566, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30235640

RESUMO

It is of fundamental importance to model the relationship between geo-environmental factors and piping erosion because of the environmental degradation attributed to soil loss. Methods that identify areas prone to piping erosion at the regional scale are limited. The main objective of this research is to develop a novel modeling approach by using three machine learning algorithms-mixture discriminant analysis (MDA), flexible discriminant analysis (FDA), and support vector machine (SVM) in addition to an unmanned aerial vehicle (UAV) images to map susceptibility to piping erosion in the loess-covered hilly region of Golestan Province, Northeast Iran. In this research, we have used 22 geo-environmental indices/factors and 345 identified pipes as predictors and dependent variables. The piping susceptibility maps were assessed by the area under the ROC curve (AUC). Validation of the results showed that the AUC for the three mentioned algorithms varied from 90.32% to 92.45%. We concluded that the proposed approach could efficiently produce a piping susceptibility map.

10.
Iran Red Crescent Med J ; 17(6): e28265, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26328068

RESUMO

BACKGROUND: Reforming the structure and improving care and service system, particularly at hospitals, are the main priorities of the health system. The board of trustees of the hospitals is the main proposed strategy in this field. Hospitals with board of trustees were created with the aim of improving accountability to the community and guaranteeing efficient management and attracting public support in running the hospital. OBJECTIVES: The aim of this study was to investigate the association between hospital effectiveness and the board of trustee's management method. MATERIALS AND METHODS: This cross-sectional study was conducted in Tabriz City, Iran, during the years 2011 to 2013. To assess the effectiveness of board of trustees' management, two hospitals in Tabriz City were compared. Hospitals selected through purposive typical case sampling method. Two hospitals had equal structure, same doctors, and both were gynecology hospitals of Tabriz City, but one of them was a gynecology hospital managed by the board of trustees and the other was managed by the chairman. The information about the five variables of hospital effectiveness was collected during the years 2011 to 2013 using standard lists and questionnaires, which were available in the hospitals; these variables included quality management, safety, medical equipment management, and patients and staff satisfaction. Then, each variable was weighted through the technique of hierarchical analysis and finally they were analyzed using SPSS 17 and Expert Choice 11. RESULTS: Among the five variables related to the effectiveness, safety showed to have the highest weight and medical equipment management had the lowest weight. According to the statistical analyses, the score of the effectiveness of the hospital with the board of trustees was 33.08 (on the scale of 0 - 100) and the score of the hospital with the chairperson was 29.52. No significant association was found between the effectiveness of hospital and the board of trustees management (P = 0.81). CONCLUSIONS: Because there was no significant difference in the effectiveness between hospitals with and without board of trustees, decision-makers must monitor how the commands are carried out to make board of trustees for hospitals and make sure its success in achieving its objectives.

11.
Artigo em Inglês | MEDLINE | ID: mdl-26179656

RESUMO

Graphene oxide nano-sheet was modified with dithizone as a novel sorbent for selective pre-concentration and determination of Cd(II) and Pb(II) in food. The sorbent was characterised by various analytical methods and the effective parameters for Cd(II) and Pb(II) adsorption were optimised during this work. The high adsorption capacity and selectivity of this sorbent makes the method capable of fast determinations of the Cd(II) and Pb(II) content in complicated matrices even at µg l(-1) levels using commonly available instrumentation. The precision of this method was < 1.9% from 10 duplicate determinations and its accuracy verified using standard reference materials. Finally, this method was applied to the determination of Cd(II) and Pb(II) ions in common food samples and satisfactory results were obtained.


Assuntos
Cádmio/análise , Ditizona/química , Análise de Alimentos , Contaminação de Alimentos/análise , Grafite/química , Chumbo/análise , Nanoestruturas/química , Óxidos/química , Adsorção , Íons/análise , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície
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