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1.
Sci Total Environ ; 818: 151760, 2022 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-34801498

RESUMEN

Suspended sediment transport in river system is a complex process influenced by many factors that their interactions lead to nonlinear and high scatter of concentration-discharge relationships. This makes the model prediction subject to high uncertainty and providing one value as the model prediction is somehow useless and cannot provide adequate information about the model accuracy and associated uncertainty. Current study compares the efficiency of Bayesian (i.e. Bayesian segmented linear regression (BSLR) and Bayesian linear model (BLR)), Gaussian Process Regression (GPR) and k-Nearest Neighbor (k-NN) in quantifying uncertainty of the suspended sediment concentration prediction in three watersheds namely Arazkoseh, Oghan and Jajrood located in Iran. Three input combinations including, contemporary discharge, slow and quick flow components and contemporary, one and two antecedent days discharge, were used. The BSLR model was able to identify threshold value, furthermore, pre-threshold and post-threshold slopes of BSLR model indicated that for Arazkoseh watershed channel and for Oghan and Jajrood watersheds, upland area are dominate sediment sources. In all three studied cases, given prediction interval width and the percent of enclosed observed data by prediction interval, k-NN model provided more reliable prediction interval. Moreover, separation stream flow into slow and quick flow components lead to improved performance of GPR and k-NN models in the studied watersheds, and the best results for Arazkoseh and Oghan watersheds were obtained when slow and quick flow components were used as the model input.


Asunto(s)
Monitoreo del Ambiente , Sedimentos Geológicos , Teorema de Bayes , Monitoreo del Ambiente/métodos , Ríos , Incertidumbre
2.
Environ Monit Assess ; 193(5): 299, 2021 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-33895895

RESUMEN

Soil moisture, vegetation cover, and land surface temperature are vital variables in water-energy balance, eco-hydrological processes, and water resources management, which can be influenced by watershed management activities. This research focused on the spatial and temporal variability of soil moisture, vegetation cover, land surface temperature, and Temperature-Vegetation Dryness Index (TVDI) under a biological watershed management practice in the Taleghan paired watershed, namely, treated (TW) and control watersheds (CW), in Alborz province, Iran. In this research, along with the remote sensing techniques, the soil moisture and vegetation cover data were measured and statistically analyzed in the three aspects of both TW and CW during a growth period from May to October 2017. The results indicated that soil moisture, vegetation cover, and land surface temperature values in the paired watershed were significantly different at the 0.01 level during the study period. The increased vegetation cover in the TW had an inverse effect on the land surface temperature and TVDI, while directly impacted the soil moisture content. The average TVDI in the CW was 0.83, while this index was found to be 0.69 in the TW. Unlike the vegetation cover and soil moisture, the results revealed that the southern aspects had the highest TVDI and land surface temperature compared to the northern and eastern aspects of both watersheds. However, the increased vegetation cover as a biological watershed management activity in the steep terrain and mountainous areas of TW led to an increased soil moisture and a decreased land surface temperature and soil dryness. As a result, decreasing soil dryness in the TW can exert vital controls on the water resources and increasing water availability. In the arid and semiarid countries such as Iran, a proper watershed management activity can effectively increase soil moisture and water availability in the watersheds. In particular, the vegetation cover protection and biological practices can be considered as practical solutions in the rehabilitation of exhausted watersheds in arid and semiarid environments.


Asunto(s)
Tecnología de Sensores Remotos , Suelo , Monitoreo del Ambiente , Irán , Recursos Hídricos
3.
Sci Total Environ ; 716: 137100, 2020 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-32059330

RESUMEN

Lake Urmia has experienced severe environmental degradation, mainly characterized by the enormous reduction of its surface area and water level. This issue has been mainly attributed to land-use and land-cover changes, in particular related to agricultural expansion and intensification. In this study, we used the DPSIR framework (D: driving forces, P: pressures, S: states, I: impacts, and R: responses) to systematically describe the ecosystem service dynamics related to anthropogenic activities and climatic parameters in the region. We reviewed the literature and used remote sensing, agricultural, climatic and hydrological data together with expert knowledge to assess the main driving forces and pressures, resulting land-use transitions and their spatiotemporal impacts on ecosystem services and biodiversity using a matrix-based assessment approach. We identified population growth, economic incentives and climate change as the most important driving forces, leading to altered agricultural activities, numerous dam constructions and droughts. Since 1987 cropland areas doubled at the expense of bare soils and natural vegetation, the lake hast lost more than half of its surface area, urban and freshwater areas increased threefold and by 50%, respectively. This favored crop and freshwater provision, while all other ecosystem services remained nearly constant or decreased, though spatial patterns were heterogeneous. For example, regulating and cultural services, and biodiversity mainly decreased at the shorelines of the lake, while provisioning services increased along the major rivers and close to cities. To address the land-use transitions with the most profound impact on ecosystem service provision, we recommend the following measures: increase the water supply to the lake, reduce cropland expansion, manage existing croplands more sustainably and protect natural vegetation. Our study provides a comprehensive overview of the regional ecosystem service dynamics and a valuable baseline for future research and environmental management in the basin.

4.
Arq Bras Cir Dig ; 31(2): e1365, 2018.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-29972393

RESUMEN

BACKGROUND: The muscle-sparing thoracotomy (MST) has not yet been thoroughly studied and assessed in comparison to the traditional thoracotomy method in newborns. AIM: To compare the outcomes of MST and standard posterolateral thoracotomy (PLT) in newborns. METHODS: Randomized, controlled, double-blind trial on 40 neonates with esophageal atresia, comparing the time of beginning a surgery until seeing the pleura, the duration of hospitalization in the neonatal intensive care unit, the time in ventilator, the time of returning the shoulder function, the time of returning the Moro reflex, and the mortality between the two techniques. RESULTS: The data showed no differences between the two groups in basic information (weight, height, gender, numbers of prematurity neonates and caesarean). The results on the size of the scar in the MST group was significantly lower than in the PLT group. Also, the time of returning the shoulder function in MST group was earlier than in PLT group. There were no significant differences in the duration since the beginning the surgery to see the pleura, the time of being hospitalized in intensive unit, the time that the infant required ventilator, returning time of the Moro reflex in 1st and 3rd months after the operation, and the mortality rates between MST and PLT groups. CONCLUSION: It seems that the advantages of using MST over PLT procedure in neonates include the earlier shoulder function recovery and also superior cosmetic results.


Asunto(s)
Atresia Esofágica/cirugía , Tratamientos Conservadores del Órgano , Toracotomía/métodos , Método Doble Ciego , Femenino , Humanos , Recién Nacido , Masculino , Músculos Pectorales , Músculos Superficiales de la Espalda
5.
Sci Total Environ ; 644: 954-962, 2018 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-30743892

RESUMEN

This study aimed to develop a novel framework for risk assessment of nitrate groundwater contamination by integrating chemical and statistical analysis for an arid region. A standard method was applied for assessing the vulnerability of groundwater to nitrate pollution in Lenjanat plain, Iran. Nitrate concentration were collected from 102 wells of the plain and used to provide pollution occurrence and probability maps. Three machine learning models including boosted regression trees (BRT), multivariate discriminant analysis (MDA), and support vector machine (SVM) were used for the probability of groundwater pollution occurrence. Afterwards, an ensemble modeling approach was applied for production of the groundwater pollution occurrence probability map. Validation of the models was carried out using area under the receiver operating characteristic curve method (AUC); values above 80% were selected to contribute in ensembling process. Results indicated that accuracy for the three models ranged from 0.81 to 0.87, therefore all models were considered for ensemble modeling process. The resultant groundwater pollution risk (produced by vulnerability, pollution, and probability maps) indicated that the central regions of the plain have high and very high risk of nitrate pollution further confirmed by the exiting landuse map. The findings may provide very helpful information in decision making for groundwater pollution risk management especially in semi-arid regions.

6.
ABCD (São Paulo, Impr.) ; 31(2): e1365, 2018. tab
Artículo en Inglés | LILACS | ID: biblio-949218

RESUMEN

ABSTRACT Background : The muscle-sparing thoracotomy (MST) has not yet been thoroughly studied and assessed in comparison to the traditional thoracotomy method in newborns. Aim : To compare the outcomes of MST and standard posterolateral thoracotomy (PLT) in newborns. Methods : Randomized, controlled, double-blind trial on 40 neonates with esophageal atresia, comparing the time of beginning a surgery until seeing the pleura, the duration of hospitalization in the neonatal intensive care unit, the time in ventilator, the time of returning the shoulder function, the time of returning the Moro reflex, and the mortality between the two techniques. Results : The data showed no differences between the two groups in basic information (weight, height, gender, numbers of prematurity neonates and caesarean). The results on the size of the scar in the MST group was significantly lower than in the PLT group. Also, the time of returning the shoulder function in MST group was earlier than in PLT group. There were no significant differences in the duration since the beginning the surgery to see the pleura, the time of being hospitalized in intensive unit, the time that the infant required ventilator, returning time of the Moro reflex in 1st and 3rd months after the operation, and the mortality rates between MST and PLT groups. Conclusion : It seems that the advantages of using MST over PLT procedure in neonates include the earlier shoulder function recovery and also superior cosmetic results.


RESUMO Racional : A técnica de toracotomia poupadora de músculo (MST) ainda não foi estudada e avaliada em relação ao método tradicional de toracotomia em recém-nascidos. Objetivo : Comparar os resultados da MST e toracotomia posterolateral padrão (PLT) em recém-nascidos. Métodos : Ensaio randomizado, controlado, duplamente cego em 40 neonatos com atresia esofágica, comparando o tempo de início da incisão até ver a pleura, a duração da hospitalização na unidade de terapia intensiva neonatal, o tempo em ventilador, o tempo da volta da função do ombro, tempo de retorno do reflexo Moro e mortalidade entre as duas técnicas. Resultados : Os dados não mostraram diferenças entre os dois grupos em informações básicas (peso, altura, gênero, número de neonatos de prematuridade e cesariana). Os resultados sobre o tamanho da cicatriz no grupo MST foram significativamente menores do que no grupo PLT. Além disso, o tempo de retorno da função do ombro no grupo MST foi mais precoce do que no grupo PLT. Não houve diferenças significativas na duração desde o início da operação até a pleura ser vista, o tempo de hospitalização em unidade intensiva, o tempo que a criança necessitou de ventilador, retorno do reflexo Moro nos 1º e 3º meses após a operação, e as taxas de mortalidade entre os grupos. Conclusão : As vantagens de usar o procedimento MST sobre PLT em neonatos incluem a recuperação da função do ombro e também resultados cosméticos superiores.


Asunto(s)
Humanos , Masculino , Femenino , Recién Nacido , Toracotomía/métodos , Atresia Esofágica/cirugía , Tratamientos Conservadores del Órgano , Músculos Pectorales , Método Doble Ciego , Músculos Superficiales de la Espalda
7.
J Neonatal Surg ; 6(2): 28, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28770125

RESUMEN

INTRODUCTION: The pathogenesis of congenital diaphragmatic hernia (CDH) is not clear. Risk factors including environmental factors have been implicated in the pathogenesis of few congenital anomalies. We aimed to assess the effect of season on the incidence of CDH and mortality rate in the southwest of Iran. MATERIAL AND METHODS: In this retrospective study, the records of 60 patients with CDH who were admitted at Neonatal Intensive Care Unit (NICU) of Imam Khomeini Hospital of Ahvaz, Iran were evaluated. RESULTS: Assuming that all the neonates born with CDH in the region reach this hospital, overall CDH prevalence rate was 1.09 per 10 000 total births. Conceptions in spring and summer in this region had statistically significantly higher incidence of CDH. Survival rate in the series was 41.6%. CONCLUSION: Seasonal variation has impact on the incidence of CDH. Mortality rate in neonates with CDH is still very high.

8.
Arch Endocrinol Metab ; 61(3): 228-232, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28699987

RESUMEN

OBJECTIVES: The objectives were to evaluate the relation between fetal anthropometric parameters and cord blood concentration of adiponectin and high sensitivity C-reactive protein (hs-CRP). Subjects and methods: A total of 104 pregnant women (52 with gestational diabetes mellitus [GDM], 52 with normal glucose tolerance (NGT) participated. Venous cord blood samples were obtained at delivery, centrifuged and the plasma was stored at -20°C. The samples were assessed for adiponectin and hs-CRP using the ELISA method. Statistical analysis was done using SPSS software. RESULTS: The adiponectin concentration was higher in the GDM group than in the NGT group (11.05 ± 4.1 µg/mL in GDM vs. 5.34 ± 2.63 µg/mL in NGT, p < 0.001). GDM was also higher in neonates delivered at later gestational ages (p < 0.001, Pearson correlation = 0.59). There was a positive correlation between cord blood adiponectin and birth weight in the GDM group (p < 0.001, Pearson correlation = 0.619) but not in the NGT group. There was no significant correlation between adiponectin and infant length or head circumference. There was also no significant difference in cord blood hs-CRP concentration between groups. No relation was found between hs-CRP and newborn anthropometric parameters. CONCLUSION: In the GDM group, adiponectin concentration was considerably higher and had a positive correlation with the ponderal index and birth weight which was not found in the NGT group.


Asunto(s)
Adiponectina/sangre , Antropometría/métodos , Proteína C-Reactiva/análisis , Diabetes Gestacional/sangre , Sangre Fetal/química , Feto/anatomía & histología , Adolescente , Adulto , Biomarcadores/sangre , Peso al Nacer , Estudios de Casos y Controles , Ensayo de Inmunoadsorción Enzimática , Femenino , Edad Gestacional , Prueba de Tolerancia a la Glucosa , Humanos , Modelos Lineales , Embarazo , Valores de Referencia , Adulto Joven
9.
Arch. endocrinol. metab. (Online) ; 61(3): 228-232, May-June 2017. tab
Artículo en Inglés | LILACS | ID: biblio-887552

RESUMEN

ABSTRACT Objectives The objectives were to evaluate the relation between fetal anthropometric parameters and cord blood concentration of adiponectin and high sensitivity C-reactive protein (hs-CRP). Subjects and methods: A total of 104 pregnant women (52 with gestational diabetes mellitus [GDM], 52 with normal glucose tolerance (NGT) participated. Venous cord blood samples were obtained at delivery, centrifuged and the plasma was stored at -20°C. The samples were assessed for adiponectin and hs-CRP using the ELISA method. Statistical analysis was done using SPSS software. Results The adiponectin concentration was higher in the GDM group than in the NGT group (11.05 ± 4.1 µg/mL in GDM vs. 5.34 ± 2.63 µg/mL in NGT, p < 0.001). GDM was also higher in neonates delivered at later gestational ages (p < 0.001, Pearson correlation = 0.59). There was a positive correlation between cord blood adiponectin and birth weight in the GDM group (p < 0.001, Pearson correlation = 0.619) but not in the NGT group. There was no significant correlation between adiponectin and infant length or head circumference. There was also no significant difference in cord blood hs-CRP concentration between groups. No relation was found between hs-CRP and newborn anthropometric parameters. Conclusion In the GDM group, adiponectin concentration was considerably higher and had a positive correlation with the ponderal index and birth weight which was not found in the NGT group.


Asunto(s)
Humanos , Femenino , Embarazo , Adolescente , Adulto , Adulto Joven , Proteína C-Reactiva/análisis , Antropometría/métodos , Diabetes Gestacional/sangre , Adiponectina/sangre , Sangre Fetal/química , Feto/anatomía & histología , Valores de Referencia , Peso al Nacer , Ensayo de Inmunoadsorción Enzimática , Biomarcadores/sangre , Estudios de Casos y Controles , Modelos Lineales , Edad Gestacional , Prueba de Tolerancia a la Glucosa
10.
J Clin Med Res ; 9(2): 124-129, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28090228

RESUMEN

BACKGROUND: This study aimed to evaluate the radiation dose received by premature neonates using diagnostic radiographies. METHODS: This cross-sectional study was conducted on 116 premature neonates with gestational age from 25 to 37 weeks; with the diagnosis of neonatal respiratory distress syndrome (NRDS) and tachypnea, they were admitted to a neonatal intensive care unit (NICU) at Ahvaz Imam Khomeini Hospital in 2015. For assessing the dose received, the model GR-200 thermoluminescent dosimeter (TLD) was used. For each premature neonate under radiation, three TLDs separately (one for each) were placed on surfaces of Ch1, T1, and G1 (chest, thyroid, and gonad of first newborn, respectively). Moreover, for the adjacent neonate at a distance of 60 - 100 cm, two TLDs were laid in the surfaces of T2 and G2 (thyroid and gonad of second newborn, respectively). The dose received by TLDs for any baby and the adjacent neonate under the entrance surface dose (ESD) was estimated. RESULTS: The mean of neonates' weight under study was 1,950.78 ± 484.9 g. During the hospitalization period, minimum one and maximum three radiographies were done for any premature neonate. The doses received in the premature neonates to Ch1, T1 and G1 were 0.08 ± 0.01, 0.06 ± 0.01, and 0.05 ± 0.01 mSv, respectively and for adjacent infants for T2 and G2 were 0.003 ± 0.001 and 0.002 ± 0.0009 mSv, respectively. CONCLUSIONS: In the study, radiation dose received by organs at risk of premature neonates was lower than the international criteria and standards, therefore, also due to the lack of radiation damage threshold, to limit collimator, and the use of the proper filtration, kilovoltage and time during radiography of premature neonates are recommended.

11.
J Clin Diagn Res ; 10(10): SM01-SM03, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27891419

RESUMEN

INTRODUCTION: Seizures are the most frequent neurologic disorder seen in childhood. Epilepsy is a group of disorders that includes an abnormally increased susceptibility to seizures. AIM: To examine the effectiveness of SPECT (Single Photon Emission Computerized Tomography) in detecting seizure foci in 21 Iranian children who had medically refractory epilepsy. MATERIALS AND METHODS: Children between 2 to 15 years of age with uncontrolled seizures were investigated using SPECT scan as a standardized protocol. RESULTS: In 16 cases (76.2%), likely seizure foci were evident, as were seen in the form of decreased regional blood flow, while in 5 cases (23.8%), SPECT scan results were normal. Left temporal lobe was the most common area which had decreased regional blood flow. CONCLUSION: SPECT scan can potentially be used to investigate children with uncontrolled seizures.

12.
Isotopes Environ Health Stud ; 50(2): 169-83, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24437989

RESUMEN

Karst springs of the Zagros Mountains contribute a significant amount to agricultural and human water demands of western and south-western Iran. For an adequate management of available water resources in semi-arid and arid regions, sufficient hydrological monitoring is needed, and hydro-chemical and isotope hydrological data provide important additional information. About 350 water samples were collected from precipitation, river water, and karst springs of the upper part of the Karkheh River Basin (20,895 km(2)) located between 33°35(') and 34°55(') North and 46°22(') and 49°10(') East with elevations ranging from 928 to 3563 m above sea level. Sampling was conducted in monthly time resolution from August 2011 to July 2012. All samples were analysed for hydro-chemical parameters (pH, electrical conductivity, and major ions) and stable isotopes (deuterium, oxygen-18). Isotope values of precipitation indicate a local meteoric water line (Zagros MWL δ(2)H=6.8 δ(18)O+10.1; R(2)=0.99) situated between the Mediterranean MWL and Global MWL. Spring and river water isotope values vary between-7.1 and-4.1 ‰, and-38 and-25 ‰ for δ(18)O and δ(2)H, respectively, responding to winter snowmelt and evaporation. This work implements stable isotopes and hydro-chemical information of springs and river water to understand hydrological and hydro-geological interrelations in karstic semi-arid areas and helps to improve the current water resources management practices of western Iran.


Asunto(s)
Deuterio/análisis , Manantiales Naturales/química , Isótopos de Oxígeno/análisis , Lluvia/química , Ríos/química , Hidrología , Irán
13.
J Craniofac Surg ; 24(3): 826-9, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23714889

RESUMEN

Cleft lip and palate are among the most common congenital defects with multifactorial etiology, and maternal stress may have a role in the development of the malformation; thus, the aim of this study was to explore the role of war on cleft lip and palate (CL/P) prevalence.In this study, records of 101,435 newborn infants delivered in the teaching hospitals of Mashhad and Ahwaz during wartime (1982-1987) and recent years (2005-2010) were reviewed. Samples were analyzed for prevalence of anomaly in both cities at 2 time intervals as well as some related factors; χ and t tests were used for data analysis.Results showed the incidences of CL/P in Mashhad during 1982 to 1987 and 2005 to 2010 were 2 and 2.2 per 1000 live births, respectively; however, its incidence in Ahwaz was 1 per 1000 during wartime and 0.7 per 1000 live births for recent years.Despite significant differences that were found in the prevalence of both cities in recent years (P = 0.001), no significant differences were observed during wartime (P = 0.28).The results revealed that CL/P was more prevalent in both cities, but in contrast to Ahwaz, cleft lip was more prevalent than isolated cleft palate in Mashhad, and significant differences were found between both cities (P = 0.007).The study concluded that the prevalence of CL/P in Ahwaz decreased after the war. However, in Mashhad, its prevalence, which was not affected during wartime, gradually increased. Thus, genetic research may be necessary to establish a genetic predisposition in northeast Iran.


Asunto(s)
Labio Leporino/epidemiología , Fisura del Paladar/epidemiología , Guerra , Estudios Transversales , Femenino , Humanos , Incidencia , Recién Nacido , Irán/epidemiología , Irak/epidemiología , Masculino , Prevalencia , Estudios Retrospectivos , Población Urbana/estadística & datos numéricos
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