Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 10 de 10
Filter
Add more filters










Publication year range
1.
ACS Omega ; 8(37): 33622-33628, 2023 Sep 19.
Article in English | MEDLINE | ID: mdl-37780456

ABSTRACT

The need for new and better semiconductor materials for use in renewable energy devices motivates us to study KRuF3 and KOsF3 fluoride materials. In the present work, we computationally studied these materials and elaborate their varied properties comprehensively with the assistance of density functional theory-based techniques. To find the structural stability of these under-consideration materials, we employed the Birch-Murnaghan fit, while their electronic characteristics were determined with the usage of modified potential of Becke-Johnson. During the study, it became evident from the band-structure results of the KRuF3 and KOsF3 materials that both present an indirect semiconductor nature having the band gap values of 2.1 and 1.7 eV, respectively. For both the studied materials, the three essential elastic constants were determined first, which were further used to evaluate all the mechanical parameters of the studied materials. From the calculated values of Pugh's ratio and Poisson's ratio for the KRuF3 and KOsF3 materials, both were verified to procure the nature of ductility. During the study, we concluded from the results of absorption coefficient and optical conduction in the UV energy range that both the studied materials proved their ability for utilization in the numerous future optoelectronic devices.

2.
RSC Adv ; 13(30): 20966-20974, 2023 Jul 07.
Article in English | MEDLINE | ID: mdl-37448644

ABSTRACT

This study communicates the theoretical investigations on the cubic double perovskite compounds Cs2XCrCl6 (X = K or Na). Density functional theory (DFT) calculations were carried out using the TB-mBJ approximation. These compounds were found to be stable in the cubic perovskite structure having lattice constants in the range of 10.58-10.20. The stability of the investigated materials was assessed by the Gold-Schmidt tolerance method, which resulted in the tolerance factor values of 0.891 and 0.951 for Cs2KCrCl6 and Cs2NaCrCl6, respectively. The calculated values of the elastic constants C11, C12, and C44 of the cubic compounds studied by our research team confirm the elastic stability. The values of the formation energies were also calculated for both the compounds and were found in the range from -2.1 to -2.3. The electronic behavior of the presently investigated materials was examined by inspecting their band structures and the density of states. It was observed that both the materials have half-metallic nature. To check the suitability of the studied compounds in optical applications, we determined the real and imaginary parts of their respective dielectric functions, absorption coefficients, optical conductivities, refractive index, and reflectivity as a function of a wide range of incident photon energies up to 40 eV.

3.
RSC Adv ; 13(33): 22958-22965, 2023 Jul 26.
Article in English | MEDLINE | ID: mdl-37520091

ABSTRACT

The non-toxic nature of lead-free materials with cubic perovskite structure has attracted the researcher's attention, and huge work is ongoing for the search of such materials. Furthermore, due to demand for their utilization in diverse applications, such as photovoltaic and optoelectronics, these inorganic-halide materials have become more enchanting for engineers. In the present work, all the key properties, including structural, electronic, optical, and mechanical, of rubidium based RbVX3 (where X is chlorine, bromine, and iodine) materials were extensively studied via first-principle density functional theory (DFT). The study reveals the half-metallic nature of the currently studied materials. For the mechanical stability of RbVX3 compounds, all three independent elastic coefficients (Cij) were determined, from which it was concluded that these materials are mechanically stable. Moreover, from the Poison and Pugh's ratios, it was found that the RbVCl3 and RbVBr3 materials have ductile nature, while RbVI3 has brittle nature upon the applied stress.

4.
Antibiotics (Basel) ; 12(4)2023 Mar 29.
Article in English | MEDLINE | ID: mdl-37107035

ABSTRACT

Staphylococcus aureus is a prominent cause of food-borne diseases worldwide. Enterotoxigenic strains of this bacteria are frequently found in raw milk, and some of these strains are resistant to antimicrobials, posing a risk to consumers. The main objectives of this study were to determine the antimicrobial resistance pattern of S. aureus in raw milk and to detect the presence of mecA and tetK genes in it. A total of 150 milk samples were obtained aseptically from lactating cattle, including Holstein Friesian, Achai, and Jersey breeds, maintained at different dairy farms. The milk samples were checked for the presence of S. aureus, and it was detected in 55 (37%) of them. The presence of S. aureus was verified by culturing on selective media, gram staining, and performing coagulase and catalase tests. Further confirmation was performed through PCR with a species-specific thermonuclease (nuc) gene. Antimicrobial susceptibility testing of the confirmed S. aureus was then determined by using the Kirby-Bauer disc diffusion technique. Out of the 55 confirmed S. aureus isolates, 11 were determined to be multidrug-resistant (MDR). The highest resistance was found to penicillin (100%) and oxacillin (100%), followed by tetracycline (72.72%), amikacin (27.27%), sulfamethoxazole/trimethoprim (18.18%), tobramycin (18.18%), and gentamycin (9.09%). Amoxicillin and ciprofloxacin were found to be susceptible (100%). Out of 11 MDR S. aureus isolates, the methicillin resistance gene (mecA) was detected in 9 isolates, while the tetracycline resistance gene (tetK) was found in 7 isolates. The presence of these methicillin- and tetracycline-resistant strains in raw milk poses a major risk to public health, as they can cause food poisoning outbreaks that can spread rapidly through populations. Our study concludes that out of nine empirically used antibiotics, amoxicillin, ciprofloxacin, and gentamicin were highly effective against S. aureus compared to penicillin, oxacillin, and tetracycline.

5.
RSC Adv ; 13(9): 6199-6209, 2023 Feb 14.
Article in English | MEDLINE | ID: mdl-36825291

ABSTRACT

Perovskites are a significant class of materials with diverse uses in modern technology. The structural, electronic, elastic, thermoelectric, and optical properties of RbTiCl3 and CsTiCl3 perovskites were estimated using the FP-LAPW method within the framework of density functional theory. The exchange-correlation energy of both analyzed systems was calculated using the Generalized Gradient Approximation (GGA) functional. The structures are optimized and lattice constants of 5.08 Å and 5.13 Å are found for XTiCl3 (X = Rb, Cs), respectively. The structural analysis reveals that they have cubic symmetry. Their half metallic nature was proved by their metallic nature in one spin channel and semiconducting nature in the opposing spin channel. Densities of states are calculated to predict the interaction of orbitals of distinct atoms in the compounds. From the results of optical response, it is found that these compounds show high optical absorption in the visible region of light. Moreover, thermoelectric properties of the studied materials are calculated as a function of chemical potential at different temperatures using the theory of semi-classical Boltzmann transport within BoltzTrap code. The thermoelectric response shows that the investigated compounds as p-type can be beneficial in overcoming the global warming issue.

6.
ACS Omega ; 7(50): 46358-46370, 2022 Dec 20.
Article in English | MEDLINE | ID: mdl-36570195

ABSTRACT

Diabetes mellitus (DM) is a complex and multiple group of disorders, and understanding the molecular mechanisms is a key role in identifying various markers involved in the diagnosis of the disease. Brucine is derived from the seeds of Strychnos nux-vomica L. (Loganiaceae), which has been used in traditional medicine to cure a variety of ailments, such as chronic rheumatism, nervous system diseases, dyspepsia, gonorrhea, anemia, and bronchitis, and has analgesic, anti-inflammatory, anti-oxidant, anti-snake venom, and anti-diabetic properties. The anti-diabetic potential of brucine was studied utilizing in vitro, in silico, in vivo, and molecular methods, including streptozotocin-induced diabetic rat models, α-glucosidase and α-amylase inhibitory assays, and via Auto-DocVina software. Brucine exhibits binding affinities of -5.0 to -10.1 Kcal/mol against chosen protein targets, according to an in silico investigation. In vitro studies revealed that brucine inhibited the enzymes α-amylase and α-glucosidase, and brucine (20 mg/kg) reduced blood glucose levels, oral glucose tolerance overload, body weight, glycosylated hemoglobin levels, total cholesterol, triglycerides, low-density lipoprotein, alanine transaminase, aspartate aminotransferase, total bilirubin, and alkaline phosphatase and elevated high-density lipoprotein levels in in vivo studies. The brucine binding energy against certain protein targets ranges from -5.0 to -10.1 Kcal/mol. It has anti-diabetic, anti-hyperlipidemic, hepatoprotective, anti-oxidant, and anti-inflammatory properties, which are mediated via inhibition of α-glucosidase and α-amylase.

7.
PLoS One ; 17(7): e0269859, 2022.
Article in English | MEDLINE | ID: mdl-35802622

ABSTRACT

BACKGROUND: Cryptosporidium spp. is recognized as an opportunistic zoonotic parasite that infects humans as well as wild and domestic animals. This enteric protozoan is a major cause of diarrhea in humans and animals and often result in death due to severe dehydration. The present study was designed to investigate the prevalence, identification of various risk factors and evaluation of sensitivity of the two diagnostic techniques for rapid and correct detection of Cryptosporidium infection in diarrheic sheep in Pakistan. METHODS: A total of 360 fecal samples were collected and processed for detection of Cryptosporidium infection after proper preservation. These samples were properly stained with modified Ziehl-Neelsen acid staining and then examined under simple microscope at 100x magnification for confirmation of Cryptosporidium oocysts. The same samples were again processed through simple PCR for confirmation of the Cryptosporidium spp. RESULTS: The age wise prevalence was detected through simple microscopy and PCR. We found highest prevalence at the age of ≤1 year followed by 1-2 years of age while the lowest prevalence was recorded at the age of ≥ 2-3 years of sheep and found significant difference between different ages (P<0.05). The sex wise prevalence showed the highest prevalence in male (♂) animals detected compared to female (♀). The overall prevalence was detected 27.08% and 18.80% through PCR and simple microscopy, respectively, and significant difference between two diagnostic techniques were observed (P<0.05). Considering the seasonality, the highest prevalence was recorded through simple microscopy in autumn, summer, and spring, while the lowest in winter. These results were confirmed through PCR. CONCLUSION: It was concluded that molecular detection is the most efficient, specific and sensitive technique for detection of Cryptosporidium infection than simple microscopy. Moreover sheep is the major potential source of infection to other wild and domestic animals including humans.


Subject(s)
Cryptosporidiosis , Cryptosporidium , Animals , Animals, Domestic , Cryptosporidiosis/diagnosis , Cryptosporidiosis/epidemiology , Cryptosporidiosis/parasitology , Cryptosporidium/genetics , Feces/parasitology , Female , Male , Pakistan/epidemiology , Prevalence , Risk Factors , Sheep
8.
ACS Omega ; 7(51): 47662-47670, 2022 Dec 27.
Article in English | MEDLINE | ID: mdl-36591182

ABSTRACT

This study reports the theoretical investigations on the structural, electronic, and optical properties of titanium-based fluoro-perovskites MTiF3 (M = Cs and Rb) using density functional theory. The impact of on-site Coulomb interactions is considered, and calculations are performed in generalized gradient approximation with the Hubbard U term (GGA + U). The ground state parameters, such as lattice constants, bulk modulus, and pressure derivatives of bulk modulus, were found. These compounds are found stable in cubic perovskite structures having lattice constants of 4.30 and 4.38 Å for RbTiF3 and CsTiF3, respectively. Analysis of elastic properties shows that both of the compounds are ductile in nature. According to the band structure profile, the examined compounds have a half-metallic character, exhibiting conducting behavior in the spin-up configuration and nonconducting behavior in the spin-down configuration. The ferromagnetic nature is conformed from the study of its magnetic moments. The optical behaviors such as reflectivity, absorption, refraction, and conductivity of the cubic phase of MTiF3 (M = Rb and Cs) are studied in the energy range of 0-40 eV.

9.
Comput Math Methods Med ; 2021: 6323357, 2021.
Article in English | MEDLINE | ID: mdl-34887940

ABSTRACT

The current article paper is aimed at assessing and comparing the seasonal check-in behavior of individuals in Shanghai, China, using location-based social network (LBSN) data and a variety of spatiotemporal analytic techniques. The article demonstrates the uses of location-based social network's data by analyzing the trends in check-ins throughout a three-year term for health purpose. We obtained the geolocation data from Sina Weibo, one of the biggest renowned Chinese microblogs (Weibo). The composed data is converted to geographic information system (GIS) type and assessed using temporal statistical analysis and spatial statistical analysis using kernel density estimation (KDE) assessment. We have applied various algorithms and trained machine learning models and finally satisfied with sequential model results because the accuracy we got was leading amongst others. The location cataloguing is accomplished via the use of facts about the characteristics of physical places. The findings demonstrate that visitors' spatial operations are more intense than residents' spatial operations, notably in downtown. However, locals also visited outlying regions, and tourists' temporal behaviors vary significantly while citizens' movements exhibit a more steady stable behavior. These findings may be used in destination management, metro planning, and the creation of digital cities.


Subject(s)
Big Data , Data Mining/statistics & numerical data , Machine Learning/statistics & numerical data , Social Media/statistics & numerical data , Travel/statistics & numerical data , China , Cities , Computational Biology , Decision Trees , Geographic Information Systems , Humans , Seasons , Social Networking , Spatio-Temporal Analysis
10.
Microb Pathog ; 112: 254-258, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28963012

ABSTRACT

The study project was designed to determine the effects of Clostridium perfringens type D infection on hematological and biochemical parameters in goats. Purposive blood samples were collected from 6 healthy and 12 diseased goats positive for C. perfringens infection. Neither the animals nor their mother were vaccinated against Clostridium perfringens from whom samples were obtained. Study was carried out in two different topographic areas; hilly (district Swat) and plain (district Mardan) of Khyber Pakhtunkhwa, Pakistan but nonsignificant (P > 0.05) statistical difference was recorded between the prevalence of Clostridium perfringens infected goats. Mean erythrocytes count (RBC) and hemoglobin level decreased significantly (P < 0.05) while the white blood cells (WBC) increased significantly (P < 0.05) in diseased animals compared to the healthy animals. However non-significant differences (P > 0.05) were observed in packet cell volume (PCV) and platelets count in healthy and diseased animals. According to biochemical analysis, a significant increase (P < 0.05) in liver enzymes, total bilirubin, serum creatinine, blood urea and glucose was recorded in diseased goats. . The results demonstrated that fluctuation in most of the mean hematological values remained within the normal range however the mean liver enzymes, total bilirubin, serum creatinine, blood urea and glucose levels gone beyond the normal levels which demonstrated severe damages to liver and kidneys.


Subject(s)
Biomarkers/blood , Clostridium Infections/blood , Clostridium Infections/veterinary , Clostridium perfringens/pathogenicity , Goat Diseases/microbiology , Animals , Animals, Domestic , Bilirubin , Blood Glucose , Clostridium Infections/epidemiology , Clostridium Infections/microbiology , Clostridium perfringens/classification , Clostridium perfringens/genetics , Clostridium perfringens/isolation & purification , Creatinine/blood , DNA, Bacterial/analysis , Erythrocytes , Feces/microbiology , Female , Goat Diseases/diagnosis , Goat Diseases/epidemiology , Goats , Humans , Kidney , Leukocyte Count , Liver/enzymology , Male , Pakistan/epidemiology , Prevalence , Risk Factors , Sex Factors , Surveys and Questionnaires , Urea/blood
SELECTION OF CITATIONS
SEARCH DETAIL
...