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1.
ACS Omega ; 8(1): 333-345, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36643508

RESUMO

Herein, a novel and environmentally benign solid catalyst was fabricated by grafting WO3 active species onto the ZnCo2O4@CeO2 support for efficient levulinic acid production from corncob waste biomass. The morphological, compositional, and textural properties of the designed catalyst were investigated using different characterization techniques to identify suitable catalyst formulation with enhanced catalytic activity and stability. The results demonstrated that WO3 active species were successfully loaded with uniform distribution onto the support to develop a robust catalyst with both acidic and basic sites. The experimental investigation showed that among the catalysts, WO3(10 wt %)/ZnCo2O4@CeO2 exhibited the best catalytic activity, providing a maximum levulinic acid yield of 78.49% at the optimal conditions of 6 wt % catalyst dosage, reaction temperature of 180 °C, and reaction time of 200 min. The presence of an optimum number of both acid and base active sites on the catalyst surface could lead to the highest catalytic activity of the synthesized catalyst. Finally, the reusability investigation indicated that the synthesized catalyst possessed sufficient recyclability of up to four times for the levulinic acid production from the selected biomass with negligible drop in the catalytic activity.

3.
J Hazard Mater ; 427: 127902, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-34872779

RESUMO

The iron metal-organic framework composite with chitosan (CS/MOF-235) was synthesized using a solvothermal method and its synthesis was confirmed by surface area, PZC, XRD, FESEM, XPS, TGA, TEM, EDX mapping and EDX analysis. The chitosan composite of the iron metal-organic framework (CS/MOF-235), MOF-235 and chitosan were used for the removal of methylene blue (MB) and methyl orange (MO) from aqueous solutions. The maximum adsorption capacities were found to be 2857-2326 mg/g for CS/MOF-235, 357 - 236 mg/g for MOF-235 and 209-171 mg/g for chitosan (CS) which reveal that the adsorption capacity of CS/MOF-235 is almost 8 and 14 times greater than MOF-235 and chitosan respectively. The adsorption selectivity of the (CS/MOF-235) towards the dye was in the order MO > MB. Moreover, hydrogen bonding, pi-pi bonding, pore-filling, electrostatic interactions and chemisorption were proposed as possible mechanisms for the removal of dyes onto CS/MOF-235. The intraparticle diffusion and Richenberg models confirmed that the adsorption process was jointly controlled by the pore and film diffusion. The negative values of the isosteric heat of adsorption (ΔH¯) fall with surface coverage indicating that a lesser amount of heat is required for the greater uptake of dyes.


Assuntos
Quitosana , Estruturas Metalorgânicas , Poluentes Químicos da Água , Adsorção , Corantes , Concentração de Íons de Hidrogênio , Cinética , Termodinâmica , Poluentes Químicos da Água/análise
4.
Cureus ; 13(9): e17643, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34646691

RESUMO

Background Vitamin D (Vit-D) plays a central role in calcium homeostasis and maintains skeletal integrity. Housewives in Quetta, Pakistan are at increased risk of vitamin D deficiency (VDD). They spend a greater part of their day in cleaning, washing, cooking, managing daily groceries, and other household chores. Thus, little time is left for self-care and outdoor activities. They wear hijab and have very little exposure to sunlight. In addition, their diet is deficient in Vit-D-rich food items, rendering them at high risk of VDD. Fear of getting tanned, melasma, and preference for a fair complexion further limit their sun exposure. This study evaluates the prevalence of VDD in housewives and determines its various risk factors to recommend screening guidelines for VDD. Methods A cross-sectional study was performed between November 2020 and April 2021 and recruited housewives aged >18 from the outpatient department of a tertiary care hospital in Quetta. Informed consent was obtained from all participants. VDD was defined as a serum 25(OH)-D level <20 ng/mL (50 nmol/L). Sociodemographic variables and information about the dietary habits, perception, attitudes towards sunlight, and daily duration of sunlight exposure were collected. Mean and standard deviation (SD) were calculated for continuous variables and counts, and proportions were calculated for categorical variables like education, age. Univariate and multivariate logistic regression analyses were performed to determine the risk factors and associations of VDD. Data were analyzed by SAS/STAT software (version 9.4). Results Among 151 housewives, 58.9% of housewives had VDD. VDD group had a higher proportion of females aged 18-30 years and a lower proportion of graduates. The reported use of Vit-D supplements was much lower in the VDD group compared with the non-deficient group, 38.2% versus 71.0 %, P-value <0.001. History of fragility fractures was reported by 10.1% of housewives in the VDD group compared to 4.8% in the non-deficient group, P-value: 0.03. Around 77.5% of housewives in the VDD group spent 15 minutes or less outdoors versus 51.6% in the non-deficient group; 55.1% of housewives in the VDD group reported that they never consumed milk versus 17.7 % in the non-deficient group, P-value <0.00001. In the univariate logistic regression model, housewives with an 11-12th grade of education had 4.80-fold higher odds of VDD compared to those who had undergraduate or graduate degrees (OR: 4.80, 95 % CI: 1.07-21.45). Housewives who never consumed milk had 9.72-fold (95 % CI: 3.69-25.58) higher odds of VDD compared to those who consumed milk on daily basis. Odds of VDD were 3.61-fold (95% CI: 1.06-12.31) higher in those who never consumed fish as compared to those who ate fish at least 1-2 days/week. In multivariate logistic regression, age group 18-30 (OR: 17.07, 95% CI: 1.18-246.86), and never consuming milk (OR: 7.33, 95 % CI: 1.99-26.89) were independently associated with VDD. Conclusion VDD is highly prevalent (58.9%) in housewives of Quetta. It is the need of time to increase awareness regarding the health benefits, sources, and deficiency symptoms of Vit-D. Our study revealed VDD in housewives irrespective of education and income. Dietary supplementations were greater predictors of VDD. Daily sun exposure should be encouraged, and food items should be fortified with Vit-D. Recommendations for Vitamin D screening would be a good step, especially in Muslim housewives.

5.
J Pak Med Assoc ; 71(9): 2265-2267, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34580528

RESUMO

In this part of the world, Burkitt's lymphoma (BL) of mandible considers a unique entity, while BL involving the jaw is endemic in Africa. BL being one of the most speedily growing malignancy, can cause immense destruction in the maxillofacial region. This case report highlights a 3-year-old child affected with BL of mandible. The presenting complaint of the patient was a rapidly enlarging swelling on the right side of the face, causing disfigurement and interfering with the normal oral functions. Confirmatory diagnosis of BL was established after correlating the clinical, radiographic, and biopsy features. Later on a tumour board discussion was held for this case, and the child underwent chemotherapy. Unfortunately, he could not survive after the second cycle of chemotherapy. This emphasises that for every fast growing jaw lesion, BL should have a significant position in the list of differential diagnosis, even in this part of the world without considering the age of the patient.


Assuntos
Linfoma de Burkitt , Linfoma de Burkitt/diagnóstico , Linfoma de Burkitt/tratamento farmacológico , Pré-Escolar , Diagnóstico Diferencial , Etnicidade , Humanos , Masculino , Mandíbula/diagnóstico por imagem , Paquistão
6.
Bioresour Technol ; 328: 124831, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33607448

RESUMO

The novel Na-SiO2@TiO2 heterogeneous base catalyst was designed and successfully applied to the trans-esterification reaction of waste cooking oil for sustainable biodiesel production. The designed catalyst was characterized by SEM, XPS, FT-IR and BET before treatment, illustrated its suitability for the catalytic trans-esterification reaction. Moreover, the influence of reaction temperature, time, catalyst concentration and WCO:MeOH molar ratio on the catalytic activity were also investigated, resultant 98% biodiesel yield was achieved. The reusability test demonstrated that the Na-SiO2@TiO2 catalyst has noticeable catalytic potency up to 5 successive runs. Besides, the kinetics study explains that the reaction is kinetically controlled by pseudo 1st order. The Ea was found to be 21.65 kJ/mol. Similarly, the important thermodynamic parameters such as ΔH#, ΔS# and ΔG# were estimated to be 18.52 kJ.mol-1, -219.17 J.mol-1K-1and 92.59 kJ.mol-1respectively.


Assuntos
Biocombustíveis , Dióxido de Silício , Biocombustíveis/análise , Catálise , Culinária , Esterificação , Cinética , Óleos de Plantas , Espectroscopia de Infravermelho com Transformada de Fourier
7.
J Pak Med Assoc ; 66(2): 217-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26819173

RESUMO

Fibromatosis is a rare benign mesenchymal neoplasm which primarily originates in the muscle, connective tissue, fascial sheaths, and musculoaponeurotic structures. It is commonly seen as abdominal tumour but in maxillofacial region, the occurrence of these tumours is very rare and exceedingly rare in infratemporal space. Often misdiagnosed due to its varied clinical behaviour, fibromatosis is benign, slow-growing, infiltrative tumour without any metastatic potential, but is locally aggressive causing organ dysfunction along with high recurrence rate. We report a case of fibromatosis involving the left infratemporal space in a 35-year-old female who presented with chief complaint of limited mouth opening for the preceding 4 years.


Assuntos
Fibroma , Neoplasias de Cabeça e Pescoço , Boca/fisiopatologia , Esvaziamento Cervical , Complicações Pós-Operatórias , Radioterapia Adjuvante/métodos , Adulto , Feminino , Fibroma/etiologia , Fibroma/patologia , Fibroma/fisiopatologia , Neoplasias de Cabeça e Pescoço/etiologia , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/fisiopatologia , Humanos , Imageamento por Ressonância Magnética/métodos , Maxila/diagnóstico por imagem , Maxila/patologia , Esvaziamento Cervical/efeitos adversos , Esvaziamento Cervical/métodos , Complicações Pós-Operatórias/patologia , Complicações Pós-Operatórias/fisiopatologia , Complicações Pós-Operatórias/cirurgia , Resultado do Tratamento
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