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1.
Environ Res ; 245: 117960, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38135098

RESUMEN

Carbon capture technologies are becoming increasingly crucial in addressing global climate change issues by lowering CO2 emissions from industrial and power generation activities. Post-combustion carbon capture, which uses membranes instead of adsorbents, has emerged as one of promising and environmentally friendly approaches among these technologies. The operation of membrane technology is based on the premise of selectively separating CO2 from flue gas emissions. This provides a number of different benefits, including improved energy efficiency and decreased costs of operation. Because of its adaptability to changing conditions and its low impact on the surrounding ecosystem, it is an appealing choice for a diverse array of uses. However, there are still issues to be resolved, such as those pertaining to establishing a high selectivity, membrane degradation, and the costs of the necessary materials. In this article, we evaluate and explore the prospective applications and roles of membrane technologies to control climate change by post-combustion carbon capturing. The primary proposition suggests that the utilization of membrane-based carbon capture has the potential to make a substantial impact in mitigating CO2 emissions originating from industrial and power production activities. This is due to its heightened ability to selectively absorb carbon, better efficiency in energy consumption, and its flexibility to various applications. The forthcoming challenges and potential associated with the application of membranes in post-carbon capture are also discussed.


Asunto(s)
Cambio Climático , Resiliencia Psicológica , Dióxido de Carbono , Ecosistema , Carbono
2.
Environ Res ; 222: 115314, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-36738770

RESUMEN

The critical challenge being faced by our current modern society on a global scale is to reduce the surging effects of climate change and global warming, being caused by anthropogenic emissions of CO2 in the environment. Present study reports the surface driven adsorption potential of deep eutectic solvents (DESs) surface functionalized cerium oxide nanoparticles (CeNPs) for low pressure CO2 separation. The phosphonium based DESs were prepared using tetra butyl phosphoniumbromide as hydrogen bond acceptor (HBA) and 6 acids as hydrogen bond donors (HBDs). The as-developed DESs were characterized and employed for the surface functionalization of CeNPs with their subsequent utilization in adsorption-based CO2 adsorption. The synthesis of as-prepared DESs was confirmed through FTIR measurements and absence of precipitates, revealed through visual observations. It was found that DES6 surface functionalized CeNPs demonstrated 27% higher adsorption performance for CO2 capturing. On the contrary, DES3 coated CeNPs exhibited the least adsorption progress for CO2 separation. The higher adsorption performance associated with DES6 coated CeNPs was due to enhanced surface affinity with CO2 molecules that must have facilitated the mass transport characteristics and resulted an enhancement in CO2 adsorption performance. Carboxylic groups could have generated an electric field inside the pores to attract more polarizable adsorbates including CO2, are responsible for the relatively high values of CO2 adsorption. The quadruple movement of the CO2 molecules with the electron-deficient and pluralizable nature led to the enhancement of the interactive forces between the CO2 molecules and the CeNPs decorated with the carboxylic group hydrogen bond donor rich DES. The current findings may disclose the new research horizons and theoretical guidance for reduction in the environmental effects associated with uncontrolled CO2 emission via employing DES surface coated potential CeNPs.


Asunto(s)
Cerio , Nanopartículas , Dióxido de Carbono , Disolventes Eutécticos Profundos , Cerio/química , Solventes/química
3.
Biotechnol Appl Biochem ; 66(4): 698-708, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31172593

RESUMEN

Phytosynthesis of gold nanoparticles (AuNPs) has achieved an indispensable significance due to the diverse roles played by biomolecules in directing the physiochemical characteristics of biosynthesized nanoparticles. Therefore, the precise identification of key bioactive compounds involved in producing AuNPs is vital to control their tunable characteristics for potential applications. Herein, qualitative and quantitative determination of key biocompounds contributing to the formation of AuNPs using aqueous Elaeis guineensis leaves extract is reported. Moreover, roles of phenolic compounds and flavonoids in reduction of Au3+ and stabilization of AuNPs have been elucidated by establishing a reaction mechanism. Fourier-transform infrared spectroscopy (FTIR) showed shifting of O─H stretching vibrations toward longer wavenumbers and C═O toward shorter wavenumbers due to involvement of polyphenolic compounds in biosynthesis and oxidation of polyphenolic into carboxylic compounds, respectively, which cape nanoparticles to inhibit the aggregation. Congruently, pyrolysis-gas chromatography-mass spectrometry revealed the major contribution of polyphenolic compounds in the synthesis of AuNPs, which was further endorsed by reduction of total phenolic and total flavonoids contents from 48.08 ± 1.98 to 9.59 ± 0.92 mg GAE/g and 32.02 ± 1.31 to 13.8 ± 0.97 mg CE/g within 60 Min, respectively. Based on experimental results, reaction mechanism explained the roles of phenolic compounds and flavonoids in producing spherical-shaped AuNPs.


Asunto(s)
Flavonoides/química , Oro/metabolismo , Tecnología Química Verde , Nanopartículas del Metal/química , Fenoles/química , Extractos Vegetales/química , Hojas de la Planta/química , Arecaceae/química , Flavonoides/aislamiento & purificación , Oro/química , Estructura Molecular , Tamaño de la Partícula , Fenoles/aislamiento & purificación , Procesos Fotoquímicos , Extractos Vegetales/aislamiento & purificación , Estrés Mecánico , Propiedades de Superficie , Agua/química , Agua/metabolismo
4.
J Pak Med Assoc ; 63(3): 374-9, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23914642

RESUMEN

OBJECTIVE: To compare the effects of combined and individual supplementation of cholecalciferol and levo carnitine on plasma glucose, plasma insulin and insulin resistance in type 2 diabetic rats. METHODS: The randomised controlled trial was conducted at the Department of Physiology, Army Medical College, Rawalpindi, between October 2010 and April 2011. It comprised 80 healthy Sprague Dawley rats who were divided into four groups (n = 20 each). Rats were fed high-fat diet for 2 weeks followed by an intraperitoneal injection of streptozocin to induce type 2 diabetes mellitus. group I served as diabetic control; group II was given cholecalciferol; group III; levo carnitine; and group IV was administered cholecalciferol and levo carnitine together. After 6 days of supplementation, terminal intracardiac blood extraction was done and samples were analysed for fasting plasma glucose and plasma insulin. Insulin resistance was calculated by homeostatic model assessment for insulin resistance. SPSS 17.0 was used for statistical analysis. RESULTS: Fasting plasma glucose levels were significantly decreased (p < 0.001) in the combined supplementation group compared to the diabetic control and individual supplementation groups. Combined supplementation showed a significant increase in fasting plasma insulin levels when compared with diabetic control and levo carnitine groups (p < 0.001), and the effect of combined supplementation on ameliorating insulin resistance was significantly better (p < 0.001) as compared to the individual supplementation of cholecalciferol and levo carnitine. CONCLUSIONS: The combined supplementation of cholecalciferol and levo carnitine for 6 days markedly improved the glycaemic control, insulin secretion and insulin resistance in type 2 diabetic rats on high-fat diet A prolonged supplementation by both the compounds along with caloric restriction may yield a more promising outcome.


Asunto(s)
Glucemia/análisis , Carnitina/farmacología , Colecalciferol/farmacología , Diabetes Mellitus Experimental/tratamiento farmacológico , Insulina/sangre , Análisis de Varianza , Animales , Resistencia a la Insulina , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley
5.
Chemosphere ; 310: 136840, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36257392

RESUMEN

The current work aims to advance the hydrophilicity, morphology, and antifouling characteristics of polyvinyl chloride (PVC) membranes for oily wastewater separation by incorporating modified bentonite. The surface of bentonite nanoparticles is altered by adopting the "grafting from" method using the surface-initiated atom transfer radical polymerization (SI-ATRP) approach. The PVC-based membrane is first prepared by blending acrylamide grafted bentonite (AAm-g-bentonite). AAm is grafted on bentonite in the presence of 2,2'-Bipyridyl and copper (I) bromide as a catalyst. The modified bentonite nanoparticles are studied using multiple techniques, such as fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), sedimentation tests, field emission scanning electron microscope (FE-SEM), etc. Flat-sheet PVC-based membrane is prepared by blending AAm-g-bentonite using the nonsolvent induced phase separation (NIPS) technique. Different methods, including FE-SEM, FTIR, sedimentation test, contact angle, porosity, antifouling property, and filtration studies of pure and oily water, are used to characterize and determine the performance of mixed-matrix membranes. Membrane performance is improved in the presence of modified bentonite (i.e., AAm-g-bentonite), with the best result achieved at PVC/AAm-g-ben-8 (i.e., 8 wt % of AAm-g-bentonite). Enhanced pure water flux (293.14 Lm-2h-1), permeate flux (123.96 Lm-2h-1), and oil rejection >93.2% are obtained by the reduced contact angle (49.1°) and improved porosity (71.22%).


Asunto(s)
Cloruro de Polivinilo , Purificación del Agua , Bentonita , Membranas Artificiales , Acrilamida , Purificación del Agua/métodos , Aceites
6.
Chemosphere ; 337: 139430, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37422221

RESUMEN

The ultimate structure of the membrane is determined using two important effects: (i) thermodynamic effect and (ii) kinetic effect. Controlling the mechanism of kinetic and thermodynamic processes in phase separation is essential for enhancing membrane performance. However, the relationship between system parameters and the ultimate membrane morphology is still largely empirical. This review focuses on the fundamental ideas behind thermally induced phase separation (TIPS) and nonsolvent-induced phase separation (NIPS) methods, including both kinetic and thermodynamic elements. The thermodynamic approach to understanding phase separation and the effect of different interaction parameters on membrane morphology has been discussed in detail. Furthermore, this review explores the capabilities and limitations of different macroscopic transport models used for the last four decades to explore the phase inversion process. The application of molecular simulations and phase field to understand phase separation has also been briefly examined. Finally, it discusses the thermodynamic approach to understanding phase separation and the consequence of different interaction parameters on membrane morphology, as well as possible directions for artificial intelligence to fill the gaps in the literature. This review aims to provide comprehensive knowledge and motivation for future modeling work for membrane fabrication via new techniques such as nonsolvent-TIPS, complex-TIPS, non-solvent assisted TIPS, combined NIPS-TIPS method, and mixed solvent phase separation.


Asunto(s)
Solventes , Termodinámica , Cinética , Inteligencia Artificial , Solventes/química
7.
Chemosphere ; 338: 139525, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37467860

RESUMEN

A key challenge is to produce the uniform morphology and regular pore design of inorganic hollow fiber membranes (HFMs) due to involvement of multiple parameters including, fabrication process and materials chemistry. Inorganic HFMs required technical innovations via novel structural design and artificial intelligence (AI) to produce the uniform structure and regular pore design. Therefore, this review aims at critical analysis on the most recent and relevant approaches to tackle the issues related to tune the morphology and pore design of inorganic HFMs. Structural design and evaluation of routes towards the dope suspension, spinning, and sintering of inorganic HFMs are critically analysed. AI, driving forces and challenges involved for harnessing of materials are revealed in this review. AI programs used for the prediction of pore design and performance of HFMs have also been explained in this review. Overall, this review will provide the understanding to build the equilibrium in spinning and sintering processes to control the design of micro-channels, and structural properties of inorganic HFMs. This review has great significance to control the new design of membranes via AI programs. This review also explain the inorganic membrane efficiency as algal-bioreactor.


Asunto(s)
Inteligencia Artificial , Polímeros , Polímeros/química , Membranas Artificiales
8.
Cureus ; 14(7): e27047, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36000142

RESUMEN

Objective The objective of this study was to determine the safety profile of methotrexate (MTX) therapy in patients with rheumatoid arthritis Study design This was a cross-sectional observational study. Place and duration of the study The study took place in the Division of Rheumatology, Lady Reading Hospital Peshawar, from May 2020 to August 2021. Methodology A total of 411 patients with rheumatoid arthritis and receiving MTX in the dose of 10-20 mg/week for at least four months were included by consecutive sampling. All patients were followed for four months for the development of cytopenias, deranged liver function tests, renal function tests, fever, and gastrointestinal upsets. Data were recorded on a pro forma. Results There were 237 (57.6%) females and 174 (42.4%) males. The female to male ratio was 1.4: 1. The average age of patients was 43.01 years + 17.1 SD with a range of 18-72 years. Gastrointestinal side effects were the most common, found in 49 patients (11.9%), followed by mucocutaneous side effects in 35 patients (8.5%) and fever (34 patients, 8.3%). Conclusion Every one in three patients developed some adverse effect within six months of methotrexate therapy. Moreover, we conclude that gastrointestinal side effects were the most common side effects seen.

9.
J Hazard Mater ; 433: 128806, 2022 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-35398795

RESUMEN

The demand and importance of fairness creams as a major cosmetic have increased significantly in recent years. However, some of these cosmetics contain heavy metals, hydroquinone and microorganism that can cause various health problems. Therefore, the aim of this study is to determine and examine the concentration of metals (i.e. Cd, Pb, Cr, Ni, Zn, Hg), hydroquinone and microorganisms in nine different fairness creams produced by local and international brands. The health risk assessment of the tested substances for consumers was accessed through systemic exposure dosage (SED), margin of safety (MoS), lifetime cancer risk (LCR), hazard quotient (HQ) and hazard index (HI). The concentration of Zn and Hg were found the highest and measured in the range of 17.82-138.06 mg.kg-1 and 2.3-141 mg.kg-1, respectively. The concentrations of other metals were determined as 0.06-0.67 mg.kg-1 of Cd, 0.43-1.55 mg.kg-1 of Cr, 0.14-1.43 mg.kg-1 of Ni and 0.3-1.34 mg.kg-1 of Pb. HPLC results showed a significant presence of hydroquinone in the range of 0.12-7.2%. The total viable counts of cosmetic samples showed the substantial presence of microorganisms, and 44% of the collected samples surpassed the permissible limit of 100 cfu/g recommended by European Union. Many of the collected samples exceeded the MoS, HQ and HI tolerance limits. However, the LCR value in all samples was significantly higher than the acceptable limit. Therefore, it is advised to avoid overuse of these products in order to ensure human safety and reduce the risks to skin health.


Asunto(s)
Cosméticos , Mercurio , Metales Pesados , Contaminantes del Suelo , Cadmio , Cosméticos/análisis , Cosméticos/toxicidad , Monitoreo del Ambiente , Humanos , Hidroquinonas , Plomo , Metales Pesados/análisis , Metales Pesados/toxicidad , Medición de Riesgo
10.
J Ayub Med Coll Abbottabad ; 23(3): 23-5, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-23272427

RESUMEN

BACKGROUND: Perinatal as well as neonatal mortality record in our country is one of the highest in the world. Home deliveries, lack of adequate facilities, poverty and lack of education are sonme of the important known causes. The present study was planned to determine neonatal mortality in Hazara. METHODS: Hospital records of neonatal admissions at Ayub Teaching Hospital (ATH) Abbottabad from 1st January 2007-31st December 2007 were analysed retrospectively. Percent neonatal mortality was calculated from the record, along with the causes of neonatal mortality. RESULTS: A total of 1705 neonates were admitted in the study period at the department of neonatology Ayub Teaching Hospital Abbottabad. Out of 1,705 neonates 947 (56%) were males while 857 (44%) were females with a male to female ratio of 1.24:1 . Majority, 1,411 out of 1,705 (83%), of the neonates was admitted during the 1st week of their life, mean age 6 days. Asphyxia, sepsis and prematurity were the three most common causes of neonatal admissions contributing 27%, 26% and 24% respectively. Overall mortality was 11%. CONCLUSION: Neonatal mortality is an important contributing factor to infant mortality in Hazara Division. Majority of patients was admitted in the first week of life which indicates that good antenatal and natal care can reduce the mortality and morbidity of our neonates. Improvement in the prenatal, natal and nursery care as a whole can reduce the neonatal mortality in preterm as well as full term neonates.


Asunto(s)
Mortalidad Hospitalaria , Enfermedades del Recién Nacido/epidemiología , Femenino , Unidades Hospitalarias , Hospitales , Humanos , Recién Nacido , Masculino , Auditoría Médica , Pakistán , Estudios Retrospectivos , Atención Terciaria de Salud
11.
Trials ; 22(1): 618, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34526081

RESUMEN

OBJECTIVES: Considering the therapeutic potential of honey and Nigella sativa (HNS) in coronavirus disease 2019 (COVID-19) patients, the objective of the study is defined to evaluate the prophylactic role of HNS. TRIAL DESIGN: The study is a randomized, placebo-controlled, adaptive clinical trial with parallel group design, superiority framework with an allocation ratio of 1:1 among experimental (HNS) and placebo group. An interim analysis will be done when half of the patients have been recruited to evaluate the need to adapt sample size, efficacy, and futility of the trial. PARTICIPANTS: All asymptomatic patients with hospital or community based COVID-19 exposure will be screened if they have had 4 days exposure to a confirmed case. Non-pregnant adults with significant exposure level will be enrolled in the study High-risk exposure (<6 feet distance for >10min without face protection) Moderate exposure (<6 feet distance for >10min with face protection) Subjects with acute or chronic infection, COVID-19 vaccinated, and allergy to HNS will be excluded from the study. Recruitment will be done at Shaikh Zayed Post-Graduate Medical Institute, Ali Clinic and Doctors Lounge in Lahore (Pakistan). INTERVENTION AND COMPARATOR: In this clinical study, patients will receive either raw natural honey (0.5 g) and encapsulated organic Nigella sativa seeds (40 mg) per kg body weight per day or empty capsule with and 30 ml of 5% dextrose water as a placebo for 14 days. Both the natural products will be certified for standardization by Government College University (Botany department). Furthermore, each patient will be given standard care therapy according to version 3.0 of the COVID-19 clinical management guidelines by the Ministry of National Health Services of Pakistan. MAIN OUTCOMES: Primary outcome will be Incidence of COVID-19 cases within 14 days of randomisation. Secondary endpoints include incidence of COVID-19-related symptoms, hospitalizations, and deaths along with the severity of COVID-19-related symptoms till 14th day of randomization. RANDOMISATION: Participants will be randomized into experimental and control groups (1:1 allocation ratio) via the lottery method. There will be stratification based on high risk and moderate risk exposure. BLINDING (MASKING): Quadruple blinding will be ensured for the participants, care providers and outcome accessors. Data analysts will also be blinded to avoid conflict of interest. Site principal investigator will be responsible for ensuring masking. NUMBERS TO BE RANDOMISED (SAMPLE SIZE): 1000 participants will be enrolled in the study with 1:1 allocation. TRIAL STATUS: The final protocol version 1.4 was approved by institutional review board of Shaikh Zayed Post-Graduate Medical Complex on February 15, 2021. The trial recruitment was started on March 05, 2021, with a trial completion date of February 15, 2022. TRIAL REGISTRATION: Clinical trial was registered on February 23, 2021, www.clinicaltrials.gov with registration ID NCT04767087 . FULL PROTOCOL: The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). With the intention of expediting dissemination of this trial, the conventional formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol. The study protocol has been reported in accordance with the Standard Protocol Items: Recommendations for Clinical Interventional Trials (SPIRIT) guidelines.


Asunto(s)
COVID-19 , Miel , Nigella sativa , Adulto , Hospitales , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , SARS-CoV-2 , Resultado del Tratamiento
12.
World J Diabetes ; 6(4): 642-7, 2015 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-25987962

RESUMEN

Inflammation plays a significant role in the etiology of type 2 diabetes mellitus (T2DM). The rise in the pro-inflammatory cytokines is the essential step in glucotoxicity and lipotoxicity induced mitochondrial injury, oxidative stress and beta cell apoptosis in T2DM. Among the recognized markers are interleukin (IL)-6, IL-1, IL-10, IL-18, tissue necrosis factor-alpha (TNF-α), C-reactive protein, resistin, adiponectin, tissue plasminogen activator, fibrinogen and heptoglobins. Diabetes mellitus has firm genetic and very strong environmental influence; exhibiting a polygenic mode of inheritance. Many single nucleotide polymorphisms (SNPs) in various genes including those of pro and anti-inflammatory cytokines have been reported as a risk for T2DM. Not all the SNPs have been confirmed by unifying results in different studies and wide variations have been reported in various ethnic groups. The inter-ethnic variations can be explained by the fact that gene expression may be regulated by gene-gene, gene-environment and gene-nutrient interactions. This review highlights the impact of these interactions on determining the role of single nucleotide polymorphism of IL-6, TNF-α, resistin and adiponectin in pathogenesis of T2DM.

13.
J Oncol ; 2011: 632870, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21559243

RESUMEN

Introduction. Pakistani population has a very rich anthrogeneological background with waves of migration from neighboring regions. Incidence rates of breast and ovarian cancer in Pakistan are on such a rapid rise that it is necessary to check the contributory factors, genetic and nongenetic. An insight into the prevalence data emphasizes the formulation of a BRCA1 and BRCA2 database for the Pakistani population. Method. In this study conducted by authors, data from diagnosed cases of both sporadic and inherited female breast and ovarian cancer cases was gathered after performing molecular genetic analysis by screening for alterations in the coding sequence of the BRCA gene. The region of interest was analyzed by the aid of various molecular biology tools such as automated DNA sequencer. Bioinformatics software was used to interpret the results, and database was prepared. Results. Mutational screening of the exons in all the samples of our study group did not reveal any pathogenic mutation. These results along with the results of the previous Pakistani studies for both BRCA1 and BRCA2 genes were summed up to prepare a Pakistani database. Percentage involvement of these genes was estimated. Nine percent of these cancers show alterations in BRCA1 gene while 3 percent have shown BRCA2 variants. The remaining 88 percent of breast and ovarian cancers can be attributed to the involvement of other genes.

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