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1.
Braz. j. biol ; 83: e252059, 2023. tab, graf
Artigo em Inglês | LILACS-Express | MEDLINE, LILACSEXPRESS | ID: biblio-1339358

RESUMO

Abstract The present study describes the haematological profile, feeding preference, and comparison of morphometric characters of blue rock pigeon (Columba livia) breeding pairs. For this purpose, 25 pairs (25 samples per sex) were sampled through Mist nets from district Okara and Bahawalnagar, Punjab, Pakistan. Birds were then anaesthetized with a combination of ketamine HCL (10 mg/kg) and diazepam (0.2 mg/kg) and subjected to morphometric measurements. 5µL blood also was taken from the jugular vein of each anaesthetized bird for haematological analysis. Few pairs were also dissected to remove gastrointestinal tracts (GITs) for food preferences. Results revealed that there are no significant differences in the haematological parameters and feeding preference of breeding pairs of Columba livia. The gut analysis further revealed, the major portion of gut contents consisted of pea and corn in most of the pairs. Regarding the mensural measurements, significant differences were recorded in the body weight, length of the longest primary feather, and chest circumference, whereas the rest of the studied parameters remain nonsignificant between sexes. So, it is concluded that apart from 3 morphometric parameters (body weight, length of longest primary feather and chest circumference), both sexes are alike in term of morphometry, haematology and food preference.


Resumo O presente estudo descreve o perfil hematológico, a preferência alimentar e a comparação de caracteres morfométricos de casais reprodutores de pombo-rocha (Columba livia). Para tanto, 25 pares (25 amostras por sexo) foram amostrados por meio de redes de névoa do distrito de Okara e Bahawalnagar, Punjab, Paquistão. As aves foram então anestesiadas com uma combinação de cetamina HCL (10 mg/kg) e diazepam (0,2 mg/kg) e submetidas a medidas morfométricas; 5 µL de sangue também foram retirados da veia jugular de cada ave anestesiada para análise hematológica. Poucos pares também foram dissecados para remover o trato gastrointestinal (GITs) para preferências alimentares. Os resultados revelaram que não há diferenças significativas nos parâmetros hematológicos e na preferência alimentar dos casais reprodutores de Columba livia. A análise intestinal revelou ainda que a maior parte do conteúdo intestinal consistia em ervilha e milho na maioria dos pares. Em relação às medidas mensurais, foram registradas diferenças significativas no peso corporal, comprimento da pena primária mais longa e circunferência torácica, enquanto os demais parâmetros estudados permanecem não significativos entre os sexos. Assim, conclui-se que além de três parâmetros morfométricos (peso corporal, comprimento da pena primária mais longa e circunferência torácica), ambos os sexos são semelhantes em termos de morfometria, hematologia e preferência alimentar.

2.
Braz. j. biol ; 83: e248420, 2023. tab, graf
Artigo em Inglês | LILACS-Express | MEDLINE, LILACSEXPRESS | ID: biblio-1339367

RESUMO

Abstract Very little is known about the malacofauna in district Swat of Khyber Pakhtunkhwa province, situated in the Northern part of Pakistan. The Swat valley possesses a variety of suitable environmental conditions, providing different types of habitats for both flora and fauna. Taken into consideration these points, the present study was conducted to explore the terrestrial snails diversity in agricultural and non-agricultural fields in the lower Swat valley. A total of 417 shells were collected from three sites: Kokarai, Kanju Township, and Deolai. Based on conchological features, three families: Bradybaenidae, Hygromiidae, and Zonitidae were identified using different terrestrial snail keys. In Kokarai and Deolai, shells of members of all the above-mentioned families were found from agricultural fields. In Kanju Township, shells of members of the family Bradybaenidae and Zonitidae were found. From these findings, it was concluded that district Swat possesses a significant malacofauna which was unexplored before and aided more to the existing literature on malacofauna. It also supports the idea that the agroecosystem is rich in species diversity. Further in-depth and extensive study is recommended to be carried out for a detailed taxonomy of the described terrestrial gastropod families.


Resumo Muito pouco se sabe sobre a malacofauna no distrito de Swat, na província de Khyber Pakhtunkhwa, situada na parte norte do Paquistão. O vale do Swat possui uma variedade de condições ambientais adequadas, proporcionando diferentes tipos de habitats para a flora e a fauna. Levando em consideração esses pontos, o presente estudo foi conduzido para explorar a diversidade dos caracóis terrestres em campos agrícolas e não agrícolas no vale inferior de Swat. Um total de 417 conchas foram coletadas em três locais: Kokarai, Kanju Township e Deolai. Com base em características concológicas, três famílias: Bradybaenidae, Hygromiidae e Zonitidae foram identificadas usando diferentes chaves de caramujos terrestres. Em Kokarai e Deolai, conchas de membros de todas as famílias mencionadas acima foram encontradas em campos agrícolas. No município de Kanju, foram encontradas conchas de membros da família Bradybaenidae e Zonitidae. A partir dessas constatações, concluiu-se que o distrito de Swat possui uma malacofauna significativa que antes era inexplorada e ajudava mais a literatura existente sobre a malacofauna. Também apoia a ideia de que o agroecossistema é rico em diversidade de espécies. Recomenda-se a realização de um estudo mais aprofundado e extenso para uma taxonomia detalhada das famílias de gastrópodes terrestres descritas.

3.
Braz. j. biol ; 83: e248978, 2023. tab, graf
Artigo em Inglês | LILACS-Express | MEDLINE, LILACSEXPRESS | ID: biblio-1339406

RESUMO

Abstract The present research was planned to assess the occurrence of intestinal parasites in small ruminants of Upper Dir of Khyber Pakhtunkhwa Province of Pakistan. For this purpose, the faecal material was collected randomly with gloved fingers directly from the rectum region of sheep and goats and the faecal materials were then put in hygienic plastic bottles with 10% formalin. The overall 315 (n=184 sheep and n= 131 goats) faecal samples were collected out of 315 samples, 281 were found positive for different parasites. Patterns-wise prevalence of GI parasites of the study area was found. Overall Single parasitism 89.20% (281/315) with 94.0% (173/184) in sheep and 82.43% (108/131) in goats. Double parasitic infection in small ruminant recorded in which Fasciola+ Haemonchus. contortus in sheep were found their prevalence was 25.54% (47/184). While in goats, the double parasitic infection in which Haemonchus contortus+Trichuris spp were found and their prevalence were 23.43% (30/131). The species found in the sample of sheep were includes, i.e., Strongyloides papillosus (41.30%), Heamonchus controtus (21.73%), Trichuris ovis (17.39%), and Fasciola hepatica (13.58%), the corresponding value for goat were Strongyloides spp 33.33% (36/108), Haemonchus spp 28.70%, (27/108), Trichuris spp 25.20% (27/184) and Fasciola spp 10.68% (14/184). The sheep of the study area are more infected as compared to goats. This study suggested that gastrointestinal parasites are major health problems of small ruminants in the study area. Therefore, a comprehensive study on species of gastrointestinal parasites circulating in the area, control options, cost-effective strategies and awareness about gastrointestinal parasites among the farmers in the study area should be instituted.


Resumo A presente pesquisa foi planejada para avaliar a ocorrência de parasitas intestinais em pequenos ruminantes do distrito Upper Dir, da província de Khyber Pakhtunkhwa, no Paquistão. Para tanto, o material fecal foi coletado aleatoriamente com dedos enluvados diretamente da região do reto de ovelhas e cabras, e os materiais fecais foram colocados em garrafas plásticas higiênicas com formol a 10%. No total, 315 (n = 184 ovelhas e n = 131 cabras) amostras fecais foram coletadas; destas, 281 foram consideradas positivas para diferentes parasitas. A prevalência de padrões de parasitas GI da área de estudo foi encontrada. Parasitismo global único 89,20% (281/315) com 94,0% (173/184) em ovinos e 82,43% (108/131) em cabras. Infecção parasitária dupla em pequenos ruminantes registrada em Fasciola + Haemonchus contortus em ovinos, sua prevalência foi de 25,54% (47/184). Já em caprinos, a dupla infecção parasitária em que Haemonchus contortus + Trichuris spp foram encontrados e sua prevalência foi de 23,43% (30/131). As espécies encontradas na amostra de ovinos foram: Strongyloides papillosus (41,30%), Heamonchus controtus (21,73%), Trichuris ovis (17,39%) e Fasciola hepatica (13,58%), o valor correspondente para cabra foi Strongyloides spp. 33,33% (36/108), Haemonchus spp. 28,70%, (27/108), Trichuris sp 25,20% (27/184) e Fasciola spp. 10,68% (14/184). As ovelhas da área de estudo estão mais infectadas do que as cabras. Este estudo sugeriu que os parasitas gastrointestinais são os principais problemas de saúde dos pequenos ruminantes na área de estudo. Portanto, um estudo abrangente sobre as espécies de parasitas gastrointestinais que circulam na área, opções de controle, estratégias de baixo custo e conscientização sobre parasitas gastrointestinais entre os agricultores na área de estudo deve ser instituído.

4.
Chemosphere ; 286(Pt 1): 131656, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34325255

RESUMO

The utilization of microalgae in treating wastewater has been an emerging topic focussed on finding an economically sustainable and environmentally friendly approach to treating wastewater. Over the last several years, different types of con microalgae and bacteria consortia have been experimented with to explore their potential in effectively treating wastewater from different sources. The basic features considered while determining efficiency is their capacity to remove nutrients including nitrogen (N) and phosphorus (P) and heavy metals like arsenic (As), lead (Pb), and copper (Cu). This paper reviews the efficiency of microalgae as an approach to treating wastewater from different sources and compares conventional and microalgae-based treatment systems. The paper also discusses the characteristics of wastewater, conventional methods of wastewater treatment that have been used so far, and the technological mechanisms for removing nutrients and heavy metals from contaminated water. Microalgae can successfully eliminate the suspended nutrients and have been reported to successfully remove N, P, and heavy metals by up to 99.6 %, 100 %, and 13%-100 % from different types of wastewater. However, although a microalgae-based wastewater treatment system offers some benefits, it also presents some challenges as outlined in the last section of this paper. Performance in eliminating nutrients from wastewater is affected by different parameters such as temperature, biomass productivity, osmotic ability, pH, O2 concentration. Therefore, the conducting of pilot-scale studies and exploration of the complexities of contaminants under complex environmental conditions is recommended.


Assuntos
Microalgas , Biomassa , Nitrogênio , Fósforo , Águas Residuárias
5.
Chemosphere ; 286(Pt 2): 131730, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34364231

RESUMO

Coffee is a globally consumed beverage that produces a substantial amount of valuable organic waste known as spent coffee grounds (SCG). Although SCG is a non-edible biomass, research initiatives focused on valorizing/utilizing its organic content, protecting the environment, and reducing the high oxygen demand required for its natural degradation. The integration with biorefinery in general and with pyrolysis process in specific is considerered the most successful solid waste management strategy of SCG that produce energy and high-value products. This paper aims at providing a quantitative analysis and discussion of research work done over the last 20 years on SCG as a feedstock in the circular bioeconomy (CBE). Management stratigies of SCG have been thoroughly reviewed and pyrolysis process has been explored as a novel technology in CBE. Results revealed that explored articles belong to Chemical, physical., biological and environmental science branches, with Energy & Fuels as the most reporting themes. Published works correlate SCG to renewable energy, biofuel, and bio-oil, with pyrolysis as a potential valorization approach. Literature review showed that only one study focused on the pyrolysis of defatted spent coffee grounds (DSCG). The insightful conclusions of this paper could assist in proposing several paths to more economically valorization of SCG through biorefinery, where extracted oil can be converted to biofuels or value-added goods. It was highlighted the importance of focusing on the coupling of SCG with CBE as solid waste managment strategy.


Assuntos
Café , Gerenciamento de Resíduos , Biocombustíveis , Pirólise , Resíduos Sólidos
6.
Braz. j. biol ; 82: e236496, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1249245

RESUMO

Abstract Euphlyctis cyanophlyctis (the skittering frog) is one of the most widespread species in Pakistan. Present study was aimed to know the presence of Euphlyctis cyanophlyctis in urban and rural areas of Lower Dir, the North-western Pakistan. A total of 33 frogs were collected, including 15 from rural and 18 from urban areas. The frogs were caught by hands covered with gloves instead of using nets. The collection was managed from August to October 2016 and from April to May 2018. Morphometric analysis, coloration as well as photographs of the frogs have been provided in detail. Skittering frogs were seen frequent in swampy areas near the water bodies. These frogs were mostly seen after sunset.


Resumo Euphlyctis cyanophlyctis (a rã que desliza) é uma das espécies mais comuns no Paquistão. O presente estudo teve como objetivo conhecer a presença de Euphlyctis cyanophlyctis em áreas urbanas e rurais de Lower Dir, noroeste do Paquistão. Um total de 33 sapos foram coletados, incluindo 15 de áreas rurais e 18 de áreas urbanas. As rãs foram apanhadas com as mãos cobertas com luvas em vez de redes. A coleta foi gerenciada de agosto a outubro de 2016 e de abril a maio de 2018. Análises morfométricas, coloração e também fotografias das rãs foram fornecidas em detalhes. Rãs saltitantes foram vistas freqüentemente em áreas pantanosas próximas aos corpos d'água. Essas rãs eram vistas principalmente após o pôr do sol.

7.
Braz J Biol ; 83: e248122, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34932614

RESUMO

Being vector of West Nile Virus and falariasis the control of Culex quinquefasciatus is likely to be essential. Synthetic insecticide treatment is looking most effective for vectors mosquito control. However, these products are toxic to the environment and non-target organisms. Consequently, ecofriendly control of vectors mosquito is needed. In this regard botanical insecticide is looking more fruitful. Therefore, the present research aimed to investigate the effectiveness of methanolic extract and various fractions, including, n-hexane, ethyl-acetate, chloroform, and aqueous fraction, obtained from methanolic extract of Ailanthus altissima, Artemisia scoparia, and Justicia adhatoda using separating funnel against larval, pupal, and adult stages of Culex quinquefasciatus. The larvae and pupae of Culex quinquefasciatus were exposed to various concentrations (31.25-1000 ppm) of methanolic extract and its fractions for 24 hours of exposure period. For knock-down bioassay (filter paper impregnation bioassay) different concentration of the methanolic extract and its various fractions (i.e. 0.0625, 0.125, 0.25, 0.5 and 1mg/mL) were applied for 1 hour exposure period. The results were statistically analysed using standard deviation, probit analysis, and linear regression. The R2 values of larvae, pupae, and adult range from 0.4 to 0.99. The values of LC50 (concentration causing 50% mortality) for late 3rd instar larvae after 24 hours exposure period range from 93-1856.7 ppm, while LC90 values range from 424 -7635.5ppm. The values of LC50for pupae range form 1326.7-6818.4ppm and and values of LC90 range from 3667.3-17427.9ppm, respectively. The KDT50 range from 0.30 to 2.8% and KDT90 values range from1.2 to 110.8%, respectively. In conclusion, Justicia adhatoda may be effective for controlling populations of vector mosquito.


Assuntos
Anopheles , Culex , Inseticidas , Animais , Inseticidas/farmacologia , Larva , Mosquitos Vetores , Extratos Vegetais/farmacologia , Folhas de Planta
8.
Mymensingh Med J ; 30(4): 1079-1085, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34605480

RESUMO

Complete assessment of obstructive jaundice requires the use of various imaging modalities that are required to detect the cause and level of obstruction thus helping in treatment planning. Magnetic Resonance Cholangio Pancreatography (MRCP) is a current available technology which is a non-invasive technique that visualizes the gallbladder, biliary tree and pancreatic duct and also provides information about surrounding structures. This study was done to correlate the MRCP findings with post-operative result and thereby demonstrate the specificity, sensitivity and efficacy of MRCP as an accurate investigatory tool for biliary obstruction. Total of fifty (50) patients of clinically diagnosed obstructive jaundice were studied from March 2017 to August 2017 in the Department of Radiology and Imaging, Combined Military Hospital, Dhaka, Bangladesh. In all these cases, USG was the initial screening investigation followed by MRCP. Cause and level of obstruction were evaluated using MRCP findings. MRCP results were correlated with surgical findings and few cases also with direct ERCP findings. Statistical analysis was done to see the sensitivity, specificity, accuracy, positive and negative predictive values of MRCP in diagnosis of biliary obstruction. In this study, USG detected level of obstruction in 56% (28 out of 50) cases. USG could detect causes of obstruction in 100% (02 out of 02) cases of choledocal cyst and 66.67% (02 out of 03) benign stricture, 60% (03 out of 05) cases of periampullary carcinoma, 57.70% (06 out of 14) cases of choledocholithiasis, and 42.86% (15 out of 26) cases of cholangiocarcinoma. On the other hand, MRCP detected level of obstruction in 98% (49 out of 50) cases. MRCP could detect causes of obstruction in 100% cases of cholangiocarcinoma, choledocholithiasis, benign stricture and choledocal cyst and 80% (04 out of 05) cases of periampullary carcinoma. In this study, ERCP could detect causes of obstruction in 32 cases of choledocholithiasis and benign stricture, but in case of cholangiocarcinoma ERCP was failed in 3 cases. In this study, for detection of cause of obstruction, ERCP had the highest sensitivity (97.79%); followed by MRCP (96.65%) and USG (60.25%). The overall diagnostic accuracy for detection of cause of obstruction was the highest for ERCP (95.50%); followed by MRCP (94.50%) and USG (64.50%). MRCP can be done in a short duration and is a noninvasive diagnostic modality compared to ERCP. MRCP needs to be advocated as a viable and non-invasive alternative with compararable sensitivity and specificity to ERCP.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Colestase , Bangladesh , Ductos Biliares Intra-Hepáticos , Colangiopancreatografia por Ressonância Magnética , Colestase/diagnóstico por imagem , Colestase/etiologia , Humanos
9.
Chemosphere ; 288(Pt 2): 132450, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34624353

RESUMO

Biodiesel commercialization is questionable due to poor brake thermal efficiency. Biodiesel utilization should be improved with the addition of fuel additives. Hydrogen peroxide is a potential fuel additive due to extra hydrogen and oxygen content, which improves the combustion process. In this experimental study, biodiesel has been produced from Jatropha oil employing catalyzed transesterification homogeneously to examine its influence on the performance and emissions at engine loads with 1500 rpm utilizing a four-stroke single-cylinder diesel engine. D60B40 (having 60% diesel and 40% biodiesel) and D60B30A10 (60% diesel, 30% biodiesel and 10% hydrogen peroxide (H2O2)), are the fuel mixtures in the current study. The addition of H2O2 reduces emissions and enhances the combustion process. This effect occurred due to the micro-explosion of the injected fuel particles (which increases in-cylinder pressure and heat release rate (HRR)). An increase of 20% in BTE and 25% reduction in BSFC for D60B30A10 was observed compared to D60B40. Significant reduction in emissions of HC up to 17.54%, smoke by 24.6% CO2 by 3.53%, and an increase in NOx was noticed when the engine is operated with D60B30A10. The HRR increased up to 18.6%, ID reduced by 10.82%, and in-cylinder pressure increased by 8.5%. Test runs can be minimized as per Taguchi's design of experiments. It is possible to provide the estimates for the full factorial design of experiments. Exhaust gas temperature standards are evaluated and examined for all fuel blends.

10.
Sci Rep ; 11(1): 19592, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34599240

RESUMO

The recent work investigates the heat transfer attributes in the flow of engine oil which comprises of nano-particles such as Cu and TiO2. The performance of Copper and Titanium oxide is over looked in the flow of engine oil. The energy equation is amended by the features of thermal radiation, viscous dissipation, and heat generation. The mathematical model signifies the porosity, entropy generation and moving flat horizontal surface with the non-uniform stretching velocity. Quasi-linearization, which is a persuasive numerical technique to solve the complex coupled differential equations, is used to acquire the numerical solution of the problem. Flow and heat transfer aspects of Cu-TiO2 in the flow are examined against the preeminent parameters. The flow is significantly affected by the thermal jump conditions and porous media. It is observed here that the temperature as well as heat transport rate is reduced with the effect of involved preeminent parameters. However, such fluids must be used with caution in applications where a control on the heat transfer is required. We may conclude that the recent study will provide assistance in thermal cooling systems such as engine and generator cooling, nuclear system cooling, aircraft refrigeration system, and so forth.

11.
Braz J Biol ; 83: e248978, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34669799

RESUMO

The present research was planned to assess the occurrence of intestinal parasites in small ruminants of Upper Dir of Khyber Pakhtunkhwa Province of Pakistan. For this purpose, the faecal material was collected randomly with gloved fingers directly from the rectum region of sheep and goats and the faecal materials were then put in hygienic plastic bottles with 10% formalin. The overall 315 (n=184 sheep and n= 131 goats) faecal samples were collected out of 315 samples, 281 were found positive for different parasites. Patterns-wise prevalence of GI parasites of the study area was found. Overall Single parasitism 89.20% (281/315) with 94.0% (173/184) in sheep and 82.43% (108/131) in goats. Double parasitic infection in small ruminant recorded in which Fasciola+ Haemonchus. contortus in sheep were found their prevalence was 25.54% (47/184). While in goats, the double parasitic infection in which Haemonchus contortus+Trichuris spp were found and their prevalence were 23.43% (30/131). The species found in the sample of sheep were includes, i.e., Strongyloides papillosus (41.30%), Heamonchus controtus (21.73%), Trichuris ovis (17.39%), and Fasciola hepatica (13.58%), the corresponding value for goat were Strongyloides spp 33.33% (36/108), Haemonchus spp 28.70%, (27/108), Trichuris spp 25.20% (27/184) and Fasciola spp 10.68% (14/184). The sheep of the study area are more infected as compared to goats. This study suggested that gastrointestinal parasites are major health problems of small ruminants in the study area. Therefore, a comprehensive study on species of gastrointestinal parasites circulating in the area, control options, cost-effective strategies and awareness about gastrointestinal parasites among the farmers in the study area should be instituted.


Assuntos
Doenças das Cabras , Parasitos , Doenças dos Ovinos , Animais , Fezes , Doenças das Cabras/epidemiologia , Cabras , Paquistão/epidemiologia , Prevalência , Ruminantes , Ovinos , Doenças dos Ovinos/epidemiologia
12.
Braz J Biol ; 83: e252059, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34669810

RESUMO

The present study describes the haematological profile, feeding preference, and comparison of morphometric characters of blue rock pigeon (Columba livia) breeding pairs. For this purpose, 25 pairs (25 samples per sex) were sampled through Mist nets from district Okara and Bahawalnagar, Punjab, Pakistan. Birds were then anaesthetized with a combination of ketamine HCL (10 mg/kg) and diazepam (0.2 mg/kg) and subjected to morphometric measurements. 5µL blood also was taken from the jugular vein of each anaesthetized bird for haematological analysis. Few pairs were also dissected to remove gastrointestinal tracts (GITs) for food preferences. Results revealed that there are no significant differences in the haematological parameters and feeding preference of breeding pairs of Columba livia. The gut analysis further revealed, the major portion of gut contents consisted of pea and corn in most of the pairs. Regarding the mensural measurements, significant differences were recorded in the body weight, length of the longest primary feather, and chest circumference, whereas the rest of the studied parameters remain nonsignificant between sexes. So, it is concluded that apart from 3 morphometric parameters (body weight, length of longest primary feather and chest circumference), both sexes are alike in term of morphometry, haematology and food preference.


Assuntos
Columbidae , Preferências Alimentares , Animais , Plumas , Paquistão , Melhoramento Vegetal
13.
Polymers (Basel) ; 13(17)2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34502908

RESUMO

Natural polymers have attracted a lot of interest in researchers of late as they are environmentally friendly, biocompatible, and possess excellent characters. Membranes forming natural polymers have provided a whole new dimension to the separation technology. In this work, chitosan-gelatin blend membranes were fabricated using chitosan as the base and varying the amount of gelatin. Transport, mechanical, and surface characteristics of the fabricated membranes were examined in detail by means of the characterizing techniques such as Fourier transform infrared spectroscopy, differential scanning colorimetry, wide angle X-ray diffraction, scanning electron microscope, and thermogravimetric analysis. In order to analyze the water affinity of the developed blend chitosan-gelatin membranes, the percentage degree of swelling was examined. Out of the fabricated membranes, the membrane loaded with 15 mass% of gelatin exhibited the better pervaporation performance with a pervaporation separation index value of 266 at 30 °C for the solution containing 10% in terms of the mass of water, which is the highest among the contemporary membranes. All the fabricated membranes were stable during the pervaporation experiments, and permeation flux of water for the fabricated membranes was dominant in the overall total permeation flux, signifying that the developed membranes could be chosen for efficient separation of water-isopropanol mixture on a larger scale.

14.
Polymers (Basel) ; 13(17)2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34502945

RESUMO

In this study, acrylonitrile butadiene styrene (ABS) and graphite powder-a solid lubricant-were filled and characterized for friction and wear responses. The fused deposition modeling (FDM) technique was utilized to synthesize ABS-graphite composites. A twin-screw extrusion approach was employed to create the composite filament of graphite-ABS that is suitable for the FDM process. Three graphite particle ratios ranging from 0% to 5% were explored in the ABS matrix. The wear and friction properties of ABS composites were examined using a pin on disc tribometer at varied sliding velocities and weights. As a result of the graphite addition in the ABS matrix, weight losses for FDM components as well as a decreased coefficient of friction were demonstrated. Furthermore, as the graphite weight percentage in the ABS matrix grows the value of friction and wear loss decreases. The wear mechanisms in graphite filled ABS composites and ABS were extensively examined using scanning electron microscopy and confocal microscopy.

15.
Polymers (Basel) ; 13(17)2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34502992

RESUMO

This experimental study investigates the mechanical properties of polymer matrix composites containing nanofiller developed by fused deposition modelling (FDM). A novel polymer nanocomposite was developed by amalgamating polycarbonate-acrylonitrile butadiene styrene (PC-ABS) by blending with graphene nanoparticles in the following proportions: 0.2, 0.4, 0.6, and 0.8 wt %. The composite filaments were developed using a twin-screw extrusion method. The mechanical properties such as tensile strength, low-velocity impact strength, and surface roughness of pure PC-ABS and PC-ABS + graphene were compared. It was observed that with the addition of graphene, tensile strength and impact strength improved, and a reduction in surface roughness was observed along the build direction. These properties were analyzed to understand the dispersion of graphene in the PC-ABS matrix and its effects on the parameters of the study. With the 0.8 wt % addition of graphene to PC-ABS, the tensile strength increased by 57%, and the impact resistance increased by 87%. A reduction in surface roughness was noted for every incremental addition of graphene to PC-ABS. The highest decrement was seen for the 0.8 wt % addition of graphene reinforcement that amounted to 40% compared to PC-ABS.

16.
Polymers (Basel) ; 13(17)2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34503052

RESUMO

In today's world, global warming has become a concern. To overcome this, we need to reduce the carbon footprints caused by the production of materials. Much of the time, this is equivalent to the same amount of CO2 emissions per tonne of production. This is a serious concern and needs to be overcome by identifying alternative materials to have as minimal a carbon footprint as possible. In this context, hemp fiber is by far the best natural fiber when compared to its peers. As per the survey conducted by the Nova institute, hemp has CO2 emissions of only 360 Kg/tonne, whereas jute has CO2 emissions of 550 Kg/tonne, kenaf 420 Kg/tonne, and flax 350 Kg/tonne. This paper presents an experimental study of the fracture toughness of hemp-reinforced hybrid composites (HRHC). The effect of the parameters on the fracture toughness behavior of HRHC is studied using the Taguchi technique. It uses different filler combinations with hemp fiber and epoxy. Hemp fiber is used as the reinforcement, epoxy resin is used as a matrix, and banana fiber, coconut shell powder, and sawdust are used as fillers. The experimental plan is prepared using an orthogonal array and analyzed using Minitab software. The obtained results were analyzed using ANOVA and main effects plots. It was observed that the fracture toughness increases with a decrease in thickness. The fracture toughness is affected by the fiber content in the range of 25%-35% and is also affected by the filler materials.

17.
Braz J Biol ; 83: e248420, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34495163

RESUMO

Very little is known about the malacofauna in district Swat of Khyber Pakhtunkhwa province, situated in the Northern part of Pakistan. The Swat valley possesses a variety of suitable environmental conditions, providing different types of habitats for both flora and fauna. Taken into consideration these points, the present study was conducted to explore the terrestrial snails diversity in agricultural and non-agricultural fields in the lower Swat valley. A total of 417 shells were collected from three sites: Kokarai, Kanju Township, and Deolai. Based on conchological features, three families: Bradybaenidae, Hygromiidae, and Zonitidae were identified using different terrestrial snail keys. In Kokarai and Deolai, shells of members of all the above-mentioned families were found from agricultural fields. In Kanju Township, shells of members of the family Bradybaenidae and Zonitidae were found. From these findings, it was concluded that district Swat possesses a significant malacofauna which was unexplored before and aided more to the existing literature on malacofauna. It also supports the idea that the agroecosystem is rich in species diversity. Further in-depth and extensive study is recommended to be carried out for a detailed taxonomy of the described terrestrial gastropod families.


Assuntos
Agricultura , Ecossistema , Animais , Humanos , Paquistão , Caramujos
18.
Molecules ; 26(14)2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34299410

RESUMO

Epoxy resins, due to their high stiffness, ease of processing, good heat, and chemical resistance obtained from cross-linked structures, have found applications in electronics, adhesives coatings, industrial tooling, and aeronautic and automotive industries. These resins are inherently brittle, which has limited their further application. The emphasis of this study is to improve the properties of the epoxy resin with a low-concentration (up to 0.4% by weight) addition of Multi-Walled Carbon Nanotubes (MWCNTs). Mechanical characterization of the modified composites was conducted to study the effect of MWCNTs infusion in the epoxy resin. Nanocomposites samples showed significantly higher tensile strength and fracture toughness compared to pure epoxy samples. The morphological studies of the modified composites were studied using Scanning Electron Microscopy (SEM).

19.
Braz J Biol ; 82: e236496, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34037074

RESUMO

Euphlyctis cyanophlyctis (the skittering frog) is one of the most widespread species in Pakistan. Present study was aimed to know the presence of Euphlyctis cyanophlyctis in urban and rural areas of Lower Dir, the North-western Pakistan. A total of 33 frogs were collected, including 15 from rural and 18 from urban areas. The frogs were caught by hands covered with gloves instead of using nets. The collection was managed from August to October 2016 and from April to May 2018. Morphometric analysis, coloration as well as photographs of the frogs have been provided in detail. Skittering frogs were seen frequent in swampy areas near the water bodies. These frogs were mostly seen after sunset.


Assuntos
Anuros , Animais , Paquistão
20.
Trop Biomed ; 38(1): 135-141, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33797536

RESUMO

Leishmaniasis and toxoplasmosis are parasitic protozoal diseases that pose serious health concerns, especially for immunocompromised people. Leishmania major and Toxoplasma gondii are endemic in Saudi Arabia and are particularly common in the Qassim Region. The present work was conducted to evaluate the in vitro antileishmanial and antitoxoplasmal activity of methanolic extracts and phytochemical fractions from two plants, Euphorpia retusa and Pulicaria undulata, which are ethnobotanical agents used to treat parasitic infection. Whole E. retusa and P. undulata plants were extracted with methanol and fractionated using petroleum ether, chloroform, ethyl acetate, n-butanol, and water and then were tested in vitro against L. major promastigote and the amastigote stages of T. gondii; the cytotoxicity of the extracts was tested against Vero cell line. The methanolic extracts of E. retusa and P. undulata exhibited promising antitoxoplasmal activity against T. gondii with EC50 values 5.6 and 12.7 µg mL-1, respectively. The chloroform fraction of P. undulata was the most potent, exhibiting an EC50 of 1.4 µg mL-1 and SI value of 12.1. It was also the most active fraction against both L. major promastigotes and amastigotes, exhibiting an EC50 of 3.9 and 3.8 µg mL-1 and SI values 4.4 and 4.5, respectively. The chloroform fraction from P. undulata is a very good candidate for the isolation of active antitoxoplasmal and antileishmanial ingredients; therefore, further phytochemical analysis for active compound isolation is highly recommended.


Assuntos
Antiprotozoários/farmacologia , Euphorbia/química , Leishmania major/efeitos dos fármacos , Extratos Vegetais/farmacologia , Pulicaria/química , Toxoplasma/efeitos dos fármacos , Animais , Antiprotozoários/isolamento & purificação , Chlorocebus aethiops , Etnobotânica , Feminino , Masculino , Camundongos Endogâmicos BALB C , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Arábia Saudita , Células Vero
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