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1.
Environ Geochem Health ; 46(1): 14, 2023 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-38147177

RESUMEN

Arsenic contamination in the groundwater occurs in various parts of the world due to anthropogenic and natural sources, adversely affecting human health and ecosystems. The current study intends to examine the groundwater hydrogeochemistry containing elevated arsenic (As), predict As levels in groundwater, and determine the aptness of groundwater for drinking in the Vehari district, Pakistan. Four hundred groundwater samples from the study region were collected for physiochemical analysis. As levels in groundwater samples ranged from 0.1 to 52 µg/L, with an average of 11.64 µg/L, (43.5%), groundwater samples exceeded the WHO 2022 recommended limit of 10 µg/L for drinking purposes. Ion-exchange processes and the adsorption of ions significantly impacted the concentration of As. The HCO3- and Na+ are the dominant ions in the study area, and the water types of samples were CaHCO3, mixed CaMgCl, and CaCl, demonstrating that rock-water contact significantly impacts hydrochemical behavior. The geochemical modeling indicated negative saturation indices with calcium carbonate and other salt minerals, encompassing aragonite, calcite, dolomite, and halite. The dissolution mechanism suggested that these minerals might have implications for the mobilization of As in groundwater. A combination of human-induced and natural sources of contamination was unveiled through principal component analysis (PCA). Artificial neural networks (ANN), random forest (RF), and logistic regression (LR) were used to predict As in the groundwater. The data have been divided into two parts for statistical analysis: 20% for testing and 80% for training. The most significant input variables for As prediction was determined using Chi-squared analysis. The receiver operating characteristic area under the curve and confusion matrix were used to evaluate the models; the RF, ANN, and LR accuracies were 0.89, 0.85, and 0.76. The permutation feature and mean decrease in impurity determine ten parameters that influence groundwater arsenic in the study region, including F-, Fe2+, K+, Mg2+, Ca2+, Cl-, SO42-, NO3-, HCO3-, and Na+. The present study shows RF is the best model for predicting groundwater As contamination in the research area. The water quality index showed that 161 samples represent poor water, and 121 samples are unsuitable for drinking. Establishing effective strategies and regulatory measures is imperative in Vehari to ensure the sustainability of groundwater resources.


Asunto(s)
Arsénico , Agua Subterránea , Humanos , Modelos Logísticos , Pakistán , Bosques Aleatorios , Ecosistema , Redes Neurales de la Computación , Iones
2.
Environ Sci Pollut Res Int ; 30(22): 61606-61625, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36811779

RESUMEN

Consumption of high fluoride (F-) and nitrate (NO3-) containing water may pose serious health hazards. One hundred sixty-one groundwater samples were collected from drinking wells in Khushab district, Punjab Province, Pakistan, to determine the causes of elevated F- and NO3- concentrations, and to estimate the human health risks posed by groundwater contamination. The results showed pH of the groundwater samples ranged from slightly neutral to alkaline, and Na+ and HCO3- ions dominated the groundwater. Piper diagram and bivariate plots indicated that the key factors regulating groundwater hydrochemistry were weathering of silicates, dissolution of evaporates, evaporation, cation exchange, and anthropogenic activities. The F- content of groundwater ranged from 0.06 to 7.9 mg/L, and 25.46% of groundwater samples contained high-level fluoride concentration (F- > 1.5 mg/L), which exceeds the (WHO Guidelines for drinking-water quality: incorporating the first and second addenda, WHO, Geneva, 2022) guidelines of drinking-water quality. Inverse geochemical modeling indicates that weathering and dissolution of fluoride-rich minerals were the primary causes of F- in groundwater. High F- can be attributed to low concentration of calcium-containing minerals along the flow path. The concentrations of NO3- in groundwater varied from 0.1 to 70 mg/L; some samples are slightly exceeding the (WHO Guidelines for drinking-water quality: incorporating the first and second addenda, WHO, Geneva, 2022) guidelines for drinking-water quality. Elevated NO3- content was attributed to the anthropogenic activities revealed by PCA analysis. The high levels of nitrates found in the study region are a result of various human-caused factors, including leaks from septic systems, the use of nitrogen-rich fertilizers, and waste from households, farming operations, and livestock. The hazard quotient (HQ) and total hazard index (THI) of F- and NO3- showed high non-carcinogenic risk (> 1) via groundwater consumption, demonstrating a high potential risk to the local population. This study is significant because it is the most comprehensive examination of water quality, groundwater hydrogeochemistry, and health risk assessment in the Khushab district to date, and it will serve as a baseline for future studies. Some sustainable measures are urgent to reduce the F- and NO3- content in the groundwater.


Asunto(s)
Agua Subterránea , Contaminantes Químicos del Agua , Humanos , Fluoruros/análisis , Nitratos/análisis , Monitoreo del Ambiente/métodos , Pakistán , Contaminantes Químicos del Agua/análisis , Minerales/análisis , Agua Subterránea/química , Medición de Riesgo , India
3.
PLoS One ; 17(6): e0268907, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35696364

RESUMEN

Cotton (Gossypium hirsutum L.) is one of the most important cash crops primarily grown for fiber. It is a perennial crop with indeterminate growth pattern. Nitrogen (N) is extremely important for vegetative growth as balanced N-nutrition improves photosynthesis, resulting in better vegetative growth. Excessive N-supply results in more vegetative growth, which increases the incidence of insect pest and diseases' infestation, pollute surface and ground water, delays maturity and produces low crop yield with poor quality. The use of plant growth regulators (PGRs) is an emerging option to control excessive vegetative growth. The PGRs help in improving plant architecture, boll retention, boll opening, yield and quality by altering growth and physiological processes such as photosynthesis, assimilate partitioning and nutrients dynamic inside the plant body. Mepiquat chloride (1,1-dimethylpiperidinum chloride) is globally used PGR for canopy development and control of excessive vegetative growth in cotton. This study investigated the effect of mepiquat chloride (MC) and N application on yield and yield components of transgenic cotton variety 'BT-FSH-326'. Two N rates (0, 198 kg ha-1) and five MC rates (0, 30,60, 90 and 120 g ha-1) were included in the study. Results revealed that MC and N application improved boll weight, number of bolls per plant, and seed cotton and lint yields. The highest seed cotton and lint yields (3595 kg ha-1 and 1701 kg ha-1, respectively) were observed under foliar application of 198 kg ha-1 N and 120 g ha-1 MC. Fiber length, fiber strength, micronaire and uniformity were significantly improved with foliar application of MC and N. In conclusion, foliar application of MC and N could be helpful in improving yield and fiber quality of cotton.


Asunto(s)
Gossypium , Nitrógeno , Fibra de Algodón , Gossypium/genética , Piperidinas , Reguladores del Crecimiento de las Plantas
4.
Environ Sci Pollut Res Int ; 29(45): 68016-68034, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35525896

RESUMEN

The world becomes advance rapidly, and the demand of perishable food increases in the global market. Food firms perceive the cheapest supply chain process for the delivery of products to end consumers. Apart from that, consumer demands high quality and safe products with competitive price. In the global intense competition, China introduced One Belt One Road (OBOR) advanced feature supply chain management system to cut the cost of production for these product firms as well as functionally deliver high quality and green products to end consumer without affecting from high environment temperature. Respectively, the graphical research model and the multi-objective method were developed to examine the estimated perishable product trading figures with consideration to quality, which is achieved by accumulating the advanced transportation features offered by OBOR supply chain management as compared to ancient rail route supply chain. To prove this, "simulation optimization function was applied to measure the probability of time-saving for perishable product quality from environmental effects and its influences over product demand." Some perishable products were selected, and their trading figures and demand value were measured by comparing both rail route environmental effects over demand, weights of products, and trade. The results declare perishable food quality and trading volume increased due to fast delivery of products to numerous countries, having cold supply chain feature under OBOR supply chain management and estimated 25 days of time-saving. Comparative analysis discloses the coherent picture of both trading routes used for delivering the products. "The findings show large amount of time-saving maximizes perishable product quality from environmental influence" estimated 3 times higher with fast train supply chain. Conceptually, perceived from the idea, when and if maglev train 600 km over an hour will be used for perishable product supply chain purpose in the near future, the estimated quality of perishable products and trading is considered to be more than 5 times higher as compared to ancient supply chain route. The study suggests future research direction on topics, food quality along with supply chain management system, and environmental impact measurement policy under different supply chain routes.


Asunto(s)
Modelos Teóricos , Transportes , China
5.
J Coll Physicians Surg Pak ; 32(12): SS140-SS142, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36597318

RESUMEN

Solid Pseudopapillary Tumour (SPT) is a very rare tumour of the pancreas. A 13-year girl presented to us with the complaint of upper abdominal pain and non-bilious vomiting for 15 days. Preoperative diagnosis of SPT involving the body of the pancreas was made by CT scan and ultrasound- guided Trucut biopsy. A sparingly rare procedure of central pancreatectomy with distal pancreatico-jejunostomy was performed. This procedure offers excellent results in benign and low-grade malignant pancreatic neck and body tumours. In addition, it preserves functional elements of the pancreas and also eliminates the infective and haematological effects of splenectomy. Key Words: Solid pseudopapillary tumour, Central pancreatectomy, Pancreatic tumours.


Asunto(s)
Pancreatectomía , Neoplasias Pancreáticas , Femenino , Humanos , Páncreas/diagnóstico por imagen , Páncreas/cirugía , Páncreas/patología , Neoplasias Pancreáticas/patología , Dolor Abdominal/etiología , Dolor Abdominal/cirugía , Esplenectomía
6.
Environ Sci Pollut Res Int ; 29(17): 25774-25789, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34846669

RESUMEN

This research analyzes the impacts of intellectual capital (IC) and the balancing power of entrepreneurial orientation (EO) on innovation growth (IG) in Pakistan's SME sector. A quantitative approach on smart PLS has been applied through the SEM model, backed by a survey to gather primary data from 256 participants of Pakistan's SME sector. A significant effect of human capital on Pakistani firms' IG was identified. In contrast, the effect of structural capital was determined to be insignificant over the IG of Pakistani firms. On the other hand, the customer capital's effect was also significant over Pakistani firms' innovation growth. Little moderation of EO between human capital and IG has been determined. The moderations of "EO between human capital and innovation growth" and "EO between structural capital and innovation growth" were insignificant. However, the moderation of EO between customer capital and IG was significant. The scope of this study is limited to firms in Pakistan and can be extended to firms in other regions, which can provide broad findings.


Asunto(s)
Emprendimiento , Humanos , Pakistán
7.
Environ Sci Pollut Res Int ; 29(4): 5552-5568, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34424468

RESUMEN

This study investigates the multifaceted role of green innovation among green intellectual capitals (GICs) on business sustainability in Pakistan's manufacturing sector. A quantitative method based on the SEM model on SmartPLS and Stata analysis was used, which was supplemented by a survey of 800 Pakistani SME sector supply chain-associated participants. The findings revealed a significant effect of green intellectual capital and green innovation on business sustainability, while structural capital was found to have a significant moderating effect on the business sustainability of Pakistani firms. It has been determined that the relationship between GIC and BS has a strong moderation of green innovation. Furthermore, the relationship and impact of GICs on the business sustainability of Pakistani manufacturing companies were statistically significant, and green innovation played a moderating role between GIC and business sustainability. Therefore, it has been suggested that Pakistani manufacturing companies participate in eco-innovation to progress business sustainability.


Asunto(s)
Comercio , Humanos , Pakistán
8.
J Ayub Med Coll Abbottabad ; 24(3-4): 193-6, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-24669652

RESUMEN

OBJECTIVE: The purpose of this study was to compare the outcome of wire osteosynthesis with bone plating in the management of zygomatic complex (ZMC) fractures. The rationale was to enable the oral and maxillofacial surgeon to select either of the treatment procedure with confidence. METHODS: In this quasi experimental study, Sixty five patients of ZMC fractures were randomly allocated in groups of bone plating and wire osteosynthesis. This was done through envelope draw method. Three points fixation with either of the treatment modality was undertaken. Titanium bone plating or stain less steel wire osteosynthesis was carried out at frontozygomatic suture, infra orbital rim and at zygomaticomaxillary buttress. RESULTS: In this quasi experimental study, three patients failed to follow up. There were 31 patients in each group. Infra orbital step defect was observed in one patient of wire osteosynthesis and two patients of bone plating. Mild facial deformity was observed in two patients of wire osteosynthesis while none in that of bone plating. CONCLUSION: There is insignificant difference of proportion of infra orbital step defect and facial deformity between wire osteosynthesis and bone plating.


Asunto(s)
Fijación Interna de Fracturas/métodos , Fracturas Cigomáticas/etiología , Fracturas Cigomáticas/cirugía , Adulto , Placas Óseas , Hilos Ortopédicos , Femenino , Fijación Interna de Fracturas/instrumentación , Humanos , Masculino , Pakistán , Resultado del Tratamiento
9.
J Ayub Med Coll Abbottabad ; 22(4): 96-100, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-22455272

RESUMEN

BACKGROUND: Root resorption is one of the most common and undesirable sequelea of orthodontic treatment. The aim of this study was to evaluate the amount of root resorption in permanent incisors during 3 month active period of fixed orthodontic appliance therapy using periapical radiographs. METHODS: Periapical radiographs of a total of 138 permanent teeth (n = 138, mandibular n1 = 52, maxillary n2 = 86) were evaluated for root resorption. All patients were treated with 3M MBT multi-bonded, pre-adjusted appliances with 0.022 inch slots. Initial levelling and alignment was achieved with 0.0175 inch co-axial wires. All four incisors (maxillary and mandibular) were measured for any change in root length. The change in root length between T0 (pre-treatment) and T1 (post-treatment) was measured in millimetres and expressed in terms of percentage of original root length. RESULTS: The mean pre treatment (T0) root length for the maxillary teeth (n1 = 62) was 19.27 +/- 2.86 mm and 20.01 +/- 2.57 mm for the mandibular teeth (n2 = 31). The post-treatment (T1) root length for the maxillary teeth was 18.96 +/- 2.85 mm and 19.49 +/- 2.4 mm for the mandibular teeth showing a mean resorption of 0.31 mm and 0.52 mm for the maxillary and mandibular teeth respectively. CONCLUSION: Root resorption was strongly correlated with active orthodontic appliance therapy with maxillary and mandibular incisors being most susceptible. It was found that root resorption can be detected even in the early levelling and alignment stages of orthodontic treatment.


Asunto(s)
Incisivo/patología , Ortodoncia , Resorción Radicular/diagnóstico , Adolescente , Femenino , Humanos , Incisivo/diagnóstico por imagen , Masculino , Aparatos Ortodóncicos , Soportes Ortodóncicos , Estudios Prospectivos , Radiografía , Resorción Radicular/diagnóstico por imagen , Resorción Radicular/etiología , Ápice del Diente/patología
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