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1.
RSC Adv ; 14(5): 3178-3185, 2024 Jan 17.
Article in English | MEDLINE | ID: mdl-38249669

ABSTRACT

Ab initio calculations have been used to investigate lead-free double-perovskites (DPs) X2AgBiY6 (X = NH4, PH4, AsH4, SbH4 and Y = Cl, Br) for solar-cell-based energy sources. The most recent and improved Becke-Johnson potential (TB-mBJ) has been proposed for the computation of optoelectronic properties. Theoretical and calculated values of the lattice constants obtained by applying the Wu-Cohen generalized gradient approximation (WC-GGA) were found to be in good agreement. The computed bandgap values of (NH4)2AgBiBr6 (1.574 eV) and (SbH4)2AgBiBr6 (1.440 eV) revealed their indirect character, demonstrating that they are suitable contenders for visible light solar-cell (SC) technology. Properties like the refractive index, light absorption, reflection, and dielectric constant are all explained in terms of the optical ranges. Within the wavelength range of 620-310 nm, the maximum absorption band has been identified. Additionally, we discover that all chemicals investigated herein have photocatalytic capabilities that can be used to efficiently produce hydrogen at cheap cost using solar water splitting by photocatalysts. In addition, the stability of the compounds was examined using the calculation of mechanical properties.

2.
J Pak Med Assoc ; 74(1): 123-125, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38219178

ABSTRACT

The study was conducted to determine and compare the caring behaviours of nursing students in four-year BS Nursing (Bachelor of Science in nursing) and two-year Post- RN BSN (Registered nurse to Bachelor of Science in Nursing) programmes. A cross-sectional analytical study was conducted in the nursing institutes of KP from July to September 2022. The sample size was 383 calculated by using the Rao soft sample size calculator. through Caring Behaviour Inventory (CBI-24) having six point Likert scale. Descriptive and inferential statistics were calculated through SPSS 20.0. There were more males, i.e. 60.6%, as compared to female students (39.4%). The overall mean score of caring competencies of Post-RN BS Nursing (Registered nurse to Bachelor of Science in Nursing) was 27.17±2.17 which is higher than 23.19±4.1 for BSN students (Bachelor of Science in nursing). Caring behaviours of overall participants are correlated with gender (p=0.001), age (p=0.001), and semester (p=0.001). The caring competency of Post-RN BS nursing students' are higher than the BS Nursing programme students. That could be due to the clinical exposure of Post-Rn students after completing a three-year Diploma in General Nursing.


Subject(s)
Education, Nursing, Baccalaureate , Students, Nursing , Male , Humans , Female , Cross-Sectional Studies
3.
Cureus ; 15(5): e39350, 2023 May.
Article in English | MEDLINE | ID: mdl-37351247

ABSTRACT

Ulcerative colitis (UC) is a chronic inflammatory bowel disease characterized by inflammation and ulceration of the colon and rectum. Diet is an important part of UC management because it can either aggravate or alleviate symptoms along with medication therapy. A comprehensive literature search was conducted using multiple databases (PubMed and Online Wiley Library) and search engines (Google Scholar) using specific keywords related to UC and diet. The search resulted in a large number of articles, which were then narrowed down by focusing on clinical trials and randomized controlled trials published between 2010 and 2023. According to the research, certain dietary interventions, such as the low FODMAP diet, the Mediterranean diet, and the anti-inflammatory diet, appear to improve symptoms and overall quality of life. Dietary interventions have the potential to help with UC management. The goal should be to provide patients with tailored dietary interventions and other treatments to improve their quality of life. More research is needed to identify the most effective dietary interventions and better understand how they work.

4.
ACS Omega ; 7(48): 43468-43479, 2022 Dec 06.
Article in English | MEDLINE | ID: mdl-36506132

ABSTRACT

A novel series of multifunctional benzimidazoles has been reported as potent inhibitors of α-glucosidase. The procedure relies on the synthesis of 5-amino-1H-benzo[d]imidazole-2-thiol 5 via the multistep reaction through 2-nitroaniline 1, benzene-1,2-diamine 2, 1H-benzo[d]imidazole-2-thiol 3, and 5-nitro-1H-benzo[d]imidazole-2-thiol 4. Further treatment of 5 with aromatic aldehydes 6a-m provided access to the target 5-(arylideneamino)-1H-benzo[d]imidazole-2-thiols 7a-m. The results of the bioactivity assessment revealed all the compounds as excellent inhibitors of the enzyme (IC50 range: 0.64 ± 0.05 µM to 343.10 ± 1.62 µM) than acarbose (873.34 ± 1.21). Among them, 7i was the most active inhibitor (IC50: 0.64 ± 0.05 µM) followed by 7d (IC50: 5.34 ± 0.16 µM), 7f (IC50: 6.46 ± 0.30 µM), 7g (IC50: 8.62 ± 0.19 µM), 7c (IC50: 9.84 ± 0.08 µM), 7m (IC50: 11.09 ± 0.79 µM), 7a (IC50: 11.84 ± 0.26 µM), 7e (IC50: 16.38 ± 0.53 µM), 7j (IC50: 18.65 ± 0.74 µM), 7h (IC50: 20.73 ± 0.59 µM), 7b (IC50: 27.26 ± 0.30 µM), 7k (70.28 ± 1.52 µM) and finally 7l (IC50: 343.10 ± 1.62 µM). Molecular docking revealed important interactions with the enzyme, thereby supporting the experimental findings.

5.
J Pak Med Assoc ; 72(7): 1378-1383, 2022 Jul.
Article in English | MEDLINE | ID: mdl-36156564

ABSTRACT

OBJECTIVE: To explore the experiences of new nursing graduates during their internship in a tertiary care setting. METHODS: The qualitative phenomenological descriptive study was conducted from September2020 to May2021 at three private hospitals of Peshawar, Pakistan, namely the Kuwait Teaching Hospital, the Mercy Teaching Hospital and the Prime Teaching Hospital. New nursing graduates of either gender were enrolled. Data was collected through semi-structured interviews using an interview guide and probing questions. Data was analysed using the 6-step Braun and Clarke method. RESULTS: Of the 11 subjects, 6(54.5%) were males and 5(45.5%) were females. Data led to the generation of four main themes; challenges, coping strategies, improved knowledge, and need for improvement in internship programme. The participants said certain types of individuals and organisational challenges affected them both personally and socially in their daily routines. Coping strategies varied among the subjects. CONCLUSIONS: New nursing graduates faced both individual and organisational challenges which is a matter of concern. Policies and their proper implementation should be planned to counter such challenges.


Subject(s)
Education, Nursing, Baccalaureate , Internship and Residency , Students, Nursing , Education, Nursing, Baccalaureate/methods , Female , Humans , Kuwait , Male , Pakistan , Qualitative Research
6.
J Appl Microbiol ; 133(5): 3030-3040, 2022 Nov.
Article in English | MEDLINE | ID: mdl-35929370

ABSTRACT

AIMS: This study examined and characterized the extract for metabolites of Halobacillus marinus HMALI004 to understand their antibacterial activities against opportunistic marine pathogens, that is, Vibrio parahaemolyticus and Vibrio cholerae. METHODS AND RESULTS: The bacterial strain HMALI004 was characterized as H. marinus, and an antibacterial spectral test revealed its inhibition against two opportunistic marine pathogens (V. parahaemolyticus and V. cholera). Fermentation broth of strain HMALI004 was subjected to column chromatography and high-performance liquid chromatography to separate antibacterial substances. Two compounds were successfully isolated and identified as 1H-pyrrole-2-carboxylic acid and 4-chloro-1H-pyrrole-2-carboxylic acid by mass spectrometry (MS) and nuclear magnetic resonance. The minimal inhibition concentration (MIC) values of 1H-pyrrole-2-carboxylic acid and 4-chloro-1H-pyrrole-2-carboxylic acid for V. parahaemolyticus were 25 µg/ml, while their MIC values for V. cholerae were 50 and 100 µg/ml, respectively. The reactive oxygen species (ROS) production of two pathogen strains treated with 1H-pyrrole-2-carboxylic acid and 4-chloro-1H-pyrrole-2-carboxylic acid were detected to investigate the antimicrobial mechanism. The results suggested that 4-chloro-1H-pyrrole-2-carboxylic acid exerted enhanced ROS production in V. parahaemolyticus, whereas 1H-pyrrole-2-carboxylic acid had a weaker effect. Both compounds caused a significant rise in ROS production in V. cholerae, causing severe damage to the cell wall and cytoplasm, leading to cell death. CONCLUSIONS: The bacterium H. marinus HMALI004 was isolated from a shrimp pond and was found to produce antimicrobial compounds, which could inhibit the growth of opportunistic marine pathogens V. parahaemolyticus and V. cholerae by increasing ROS. SIGNIFICANCE AND IMPACT OF THE STUDY: Successfully isolated antibacterial-producing strain, H. marinus HMALI004, and its antimicrobial compounds could be used as biological control agents for marine pathogens.


Subject(s)
Anti-Infective Agents , Halobacillus , Vibrio cholerae , Vibrio parahaemolyticus , Reactive Oxygen Species , Biological Control Agents/pharmacology , Bacteria , Vibrio parahaemolyticus/physiology , Anti-Bacterial Agents/pharmacology , Anti-Infective Agents/pharmacology , Plant Extracts/pharmacology
7.
AMB Express ; 12(1): 82, 2022 Jun 23.
Article in English | MEDLINE | ID: mdl-35737135

ABSTRACT

Diseases outbreaks in pond aquaculture have resulted in huge losses to the aquaculture industry. The emergence of non-antimicrobial and environment friendly agents (probiotics) is the potential consideration for the healthy shrimp aquaculture. The present study was aimed to compare the bacterial community compositions in shrimp ponds and surrounding seawater, as well as isolate probiotic bacteria from the shrimp ponds. Based on the high-throughput of 16S rRNA gene sequencing, all sequences were assigned to 3584 unique operational taxonomic units (OTUs) at 97% similarity levels, which were affiliated with 24 phyla, 54 classes, 235 families, and 367 genera. The 10 most abundant phyla were Bacteroidota, Proteobacteria, Actinobacteriota, Planctomycetota, Cyanobacteria, Chloroflexi, Firmicutes, Desulfobacterota, Patescibacteria and Verrucomicrobiota. Notably, the alpha diversity (Shannon diversity) of shrimp ponds was significantly differences (P < 0.05) with that of surrounding seawater. There were 2498 and 791 unique OTUs in shrimp ponds and surrounding seawater, respectively. A total of 15 isolates were obtained in the culturable bacterial diversity, and the antibacterial activities were recorded for potential probiotic bacterial isolates against different tested bacterial isolates including pathogenic bacteria. An isolate Hallobacillus marinus HMALI004 showed strong inhibitory effects against three pathogenic bacteria, Vibrio cholerae CECT 514, non AHPND V. parahaemolyticus BCRC12959 and AHPND V. parahaemolyticus PD-2. The isolates Algophigus sanaruensis AGALI005, Algoriphagus taiwanensis ATALI009 and Bacillus aequororis BAALI008 were also identified as potential probiotics strains.

8.
Comput Math Methods Med ; 2022: 9288452, 2022.
Article in English | MEDLINE | ID: mdl-35154361

ABSTRACT

One of the leading causes of deaths around the globe is heart disease. Heart is an organ that is responsible for the supply of blood to each part of the body. Coronary artery disease (CAD) and chronic heart failure (CHF) often lead to heart attack. Traditional medical procedures (angiography) for the diagnosis of heart disease have higher cost as well as serious health concerns. Therefore, researchers have developed various automated diagnostic systems based on machine learning (ML) and data mining techniques. ML-based automated diagnostic systems provide an affordable, efficient, and reliable solutions for heart disease detection. Various ML, data mining methods, and data modalities have been utilized in the past. Many previous review papers have presented systematic reviews based on one type of data modality. This study, therefore, targets systematic review of automated diagnosis for heart disease prediction based on different types of modalities, i.e., clinical feature-based data modality, images, and ECG. Moreover, this paper critically evaluates the previous methods and presents the limitations in these methods. Finally, the article provides some future research directions in the domain of automated heart disease detection based on machine learning and multiple of data modalities.


Subject(s)
Diagnosis, Computer-Assisted/methods , Heart Failure/diagnosis , Machine Learning , Algorithms , Arrhythmias, Cardiac/diagnosis , Arrhythmias, Cardiac/diagnostic imaging , Computational Biology , Coronary Artery Disease/diagnosis , Coronary Artery Disease/diagnostic imaging , Data Mining/statistics & numerical data , Databases, Factual/statistics & numerical data , Diagnosis, Computer-Assisted/statistics & numerical data , Diagnosis, Computer-Assisted/trends , Electrocardiography/statistics & numerical data , Heart Failure/diagnostic imaging , Humans , Image Interpretation, Computer-Assisted/statistics & numerical data , Machine Learning/trends , Neural Networks, Computer
9.
Pak J Pharm Sci ; 35(1): 41-48, 2022 Jan.
Article in English | MEDLINE | ID: mdl-35221271

ABSTRACT

Shigella infection (shigellosis) is an intestinal disease caused by a shigella isolates belongs to a family Enterobacteriacea. Watery diarrhea, abdominal pain and tenesmus are the prominent symptoms of shigella infection. The present study was designed to determine period prevalence and antimicrobial susceptibility of Shigella species recovered from stool specimens obtained from diarrheal paediatric patients under 5 years of age. This cross-sectional study was carried out for a period of six months (Jan to June, 2016). All Shigella isolates were identified based on colony morphology, microscopic characteristics, and biochemical characteristics. After applying Kirby Baur disc diffusion method only 22 (18.96%) stool specimens were found positive for Shigella isolates among the 116 stool specimens. The isolates were also found susceptible to Levofloxacin (72.72%), Azithromycin (59.09%), and Cefotaxime (40.90%). However, the said isolates were resistant to Lincomycin (100%) and Penicillin-G (100%), followed by Amoxicillin (95.45%) and Oxacillin (95.45%). The chi-square test was used to check the close association among antimicrobial agents used and as highly significant (p-value < 2.2e-16). Based on antimicrobial susceptibility findings, Levofloxacin, Azithromycin and Cefotoxime were found effective for the control of shigellosis.


Subject(s)
Anti-Bacterial Agents/pharmacology , Dysentery, Bacillary/microbiology , Shigella/drug effects , Child, Preschool , Cross-Sectional Studies , Drug Resistance, Bacterial , Feces/microbiology , Humans , Infant , Pakistan/epidemiology
10.
ACS Omega ; 7(1): 705-715, 2022 Jan 11.
Article in English | MEDLINE | ID: mdl-35036737

ABSTRACT

This research reports the synthesis of new benzimidazole-derived N-acylhydrazones (NAH), their characterization using various spectroscopic methods, and in vitro evaluation as potent carbonic anhydrase-II inhibitors. Among the target compounds (9-29), few showed higher inhibition than the standard acetazolamide (IC50: 18.6 ± 0.43 µM), for example, compound 9 (IC50: 13.3 ± 1.25 µM), 10 (IC50: 17.2 ± 1.24 µM), 12 (IC50: 14.6 ± 0.62 µM), and 15 (IC50: 14.5 ± 1.05 µM). Molecular docking was performed on the most active compounds, which revealed their binding interactions with the active site of the enzyme, thus supporting the experimental findings.

11.
Microb Ecol ; 84(3): 676-687, 2022 Oct.
Article in English | MEDLINE | ID: mdl-34693460

ABSTRACT

The world is constantly facing threats, including the emergence of new pathogens and antibiotic resistance among extant pathogens, which is a matter of concern. Therefore, the need for natural and effective sources of drugs is inevitable. The ancient and pristine ecosystems of caves contain a unique microbial world and could provide a possible source of antimicrobial metabolites. The association between humans and caves is as old as human history itself. Historically, cave environments have been used to treat patients with respiratory tract infections, which is referred to as speleotherapy. Today, the pristine environment of caves that comprise a poorly explored microbial world is a potential source of antimicrobial and anticancer drugs. Oligotrophic conditions in caves enhance the competition among microbial communities, and unique antimicrobial agents may be used in this competition. This review suggests that the world needs a novel and effective source of drug discovery. Therefore, being the emerging spot of modern human civilization, caves could play a crucial role in the current medical crisis, and cave microorganisms may have the potential to produce novel antimicrobial and anticancer drugs.


Subject(s)
Caves , Microbiota , Humans , Anti-Bacterial Agents/pharmacology
13.
Int J Syst Evol Microbiol ; 71(10)2021 Oct.
Article in English | MEDLINE | ID: mdl-34623951

ABSTRACT

A Gram-stain-negative, non-motile, rod-shaped, aerobic bacterium (designated as LMIT005T) was isolated from shrimp ponds in Shantou, China. The new isolate was characterized taxonomically using a polyphasic approach. Based on 16S rRNA gene sequence analysis, strain LMIT005T was found to be affiliated with the family Cyclobacteriaceae of the order Cytophagales while appearing as a distinct lineage. The 16S rRNA gene sequence similarity between strain LMIT005T and Algoriphagus yeomjeoni KCTC 12309T, the closest type strain in the family, was 91.3 %. Strain LMIT005T grew optimally at 25 °C, pH 7 and in the presence of 2.0 % (w/v) NaCl. The DNA G+C content (data from genome sequence) was 40.5 mol%. Compared with reference strain A. yeomjeoni KCTC 12309T, the average nucleotide identity (ANI) of LMIT005T was 70 %. The sole respiratory quinone of LMIT005T was menaquinone (MK-7), and the major fatty acids were summed feature 3 (C16 : 1 ω6c / C16 : 1 ω7c). The polar lipids of strain LMIT005T were mainly composed of phosphatidylethanolamine, phosphatidylcholine, two unidentified amino lipids, two unidentified lipids, one unidentified glycolipid and one unidentified phospholipid. The draft genome of strain LMIT005T comprised 3 089 781 bp (3.09 Mb) nucleotides and 2773 genes. Antimicrobial resistant-related genes (blal, mexA, and mexb) were annotated in the genome of strain LMIT005T, which indicated that it might be able to resist ß-lactam antibiotics. This was further verified by antimicrobial resistant test. Given its distinct genomic, morphological, and physiological differences from previously described type strains, strain LMIT005T is proposed as a representative of a novel genus of the family Cyclobacteriaceae, with the name Penaeicola halotolerans gen. nov., sp. nov. The type strain is LMIT005T (=KCTC 82616T=CICC 25047T).


Subject(s)
Bacteroidetes/classification , Phylogeny , Seawater , Aquaculture , Bacterial Typing Techniques , Bacteroidetes/isolation & purification , Base Composition , China , DNA, Bacterial/genetics , Fatty Acids/chemistry , Phospholipids/chemistry , Ponds , RNA, Ribosomal, 16S/genetics , Seawater/microbiology , Sequence Analysis, DNA , Vitamin K 2/analogs & derivatives , Vitamin K 2/chemistry
14.
J Pak Med Assoc ; 71(7): 1827-1831, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34410256

ABSTRACT

OBJECTIVE: To explore the experiences of post-coronary artery bypass grafting patients in Pakistan. METHODS: The qualitative, descriptive, phenomenological study was conducted at the Lady Reading Hospital, Peshawar, Pakistan, from May 2018 to April 2019, and comprised patients having undergone coronary artery bypass grafting. Data was collected through semi-structured interviews that included probing questions. Codes, categories and themes were framed through extensive thematic analysis. RESULTS: Of the 14 patients, 11(78.6%) were male with a mean age of 50.81±5.61 years and 3(21.4%) were female with a mean age of 63.33±6.02 years. Four main themes were generated; challenges, perceptions about coronary artery bypass grafting, coping with the challenges, and perceptions about nurses and doctors. The subjects were of the view that they were affected with certain types of physical, psychological and financial challenges. These encounters affected the patients post-procedure in almost every aspect of their lives and made it difficult for them to carry out activities on a daily basis. Further, coping strategies varied from individual to individual. CONCLUSIONS: Patients after coronary artery bypass grafting were found to encounter issues related to physical, psychological and social spheres. Care for such patients must be planned in a way to avoid such challenges.


Subject(s)
Coronary Artery Bypass , Physicians , Adaptation, Psychological , Aged , Female , Humans , Male , Middle Aged , Pakistan , Qualitative Research
15.
Saudi J Biol Sci ; 28(1): 347-352, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33424316

ABSTRACT

Genetic diversity play key role in the germplasm improvement which is directly correlated with the crop production. Various statistical techniques have been used to study diversity among different genotypes. Among these techniques multivariate is most frequently used one for the genetic association of genotypes. In the present study a total of 64 advance lines included one check cultivar were evaluated under the field conditions of Cereal Crop Research Institute, Pirsabaq Nowshera, Pakistan during September 2017. Data were recorded for nine different parameters. Multivariate analysis divided the total 64 genotypes into four groups. The first five PCs with Eigen values > 1 contributed 86.95% of the variability amongst genotypes. Characters with maximum values in PC1 were Spikelets spike-1 (SPPS) (0.732), spike length (SPL) (0.722) and biological yield (BY) (0.607), PC2 comprised of 100-grain weight (TGW) (0.605), grain yield (GY) (0.482) while days to heading (DH) (0.393), for PC3 major contributors were BY (0.550) and number of tillers meter square-1 (NTPS) (0.289), the contribution of PC4 were flag leaf area (FLA) (0.716) and SPL (0.298) and the maximum values for various traits in PC5 were SPPS (0.732), SPL (0.722) and BY (0.607). From the findings of present study best performing lines can be directly recommended for general cultivation or to be used in future breeding programs.

16.
Drug Dev Res ; 82(2): 207-216, 2021 04.
Article in English | MEDLINE | ID: mdl-32897587

ABSTRACT

A series of new heterocycles (4-18) was synthesized by the structural modification of benzimidazole-2-thiol (BT, 2-MBI). The structures of the synthesized compounds were confirmed with the help of high-resolution mass spectrometry (HRMS) and 1 HNMR spectroscopy. High inhibitions of the oxidants such as ABTS and DPPH were observed for compounds 9 [IC50 (s) = 167.4 µM (ABTS), 139.5 µM (DPPH)], 10 [IC50 (s) = 186.5 µM (ABTS), 155.4 µM (DPPH)], 11 [IC50 (s) = 286.1 µM (ABTS), 189.1 µM (DPPH)], 12 [IC50 (s) = 310.8 µM (ABTS), 162.2 µM (DPPH)], 14 [IC50 (s) = 281.3 µM (ABTS), 205.7 µM (DPPH)], 15 [IC50 (s) = 284.1 µM (ABTS), 177.3 µM (DPPH)], and 16 [IC50 (s) = 344.7 µM (ABTS), 270.2 µM (DPPH)] as compared with Ascorbic acid [IC50 (s) = 340.9 µM (ABTS), 164.3 µM (DPPH)]. The anti-Alzheimer's activity was performed in vitro against cholinesterase enzymes (AChE, BChE). Compound 11 was able to show significant inhibitions [IC50 (s) = 121.2 µM (AChE), 38.3 µM (BChE)] as against that of galantamine [IC50 (s) = 139.4 µM (AChE), 40.3 µM (BChE)]. Compound 14 was found as a very good inhibitor of butyrylcholinesterase (IC50 = 35.4 µM) as compared with standard galantamine. Molecular docking was further performed to investigate the mechanism of anticholinesterase activity.


Subject(s)
Alzheimer Disease/drug therapy , Benzimidazoles/administration & dosage , Chemistry, Pharmaceutical/methods , Drug Delivery Systems/methods , Free Radical Scavengers/administration & dosage , Sulfhydryl Compounds/administration & dosage , Benzimidazoles/chemical synthesis , Free Radical Scavengers/chemical synthesis , Humans , Molecular Docking Simulation/methods , Protein Structure, Secondary , Sulfhydryl Compounds/chemical synthesis
17.
Langmuir ; 36(42): 12760-12771, 2020 Oct 27.
Article in English | MEDLINE | ID: mdl-33034455

ABSTRACT

This paper represents a study of mixed Co3O4/CuO nanosheet (NS) synthesis via solution combustion synthesis for oxidation of methanol and carbon dioxide (CO2) conversion. The mixed oxide NS of Co3O4/CuO is a hybrid structure of Co3O4 and CuO NSs. We applied this mixed oxide NS of Co3O4/CuO for methanol oxidation and carbon dioxide (CO2) conversion, and the results revealed that the activity of the mixed oxide NS surpassed the activity of the corresponding individual Co3O4 and CuO metal oxide NSs, both in methanol oxidation and in CO2 conversion. The mass activity of the mixed Co3O4/CuO NS produced at 0.627 V versus Ag/AgCl during methanol oxidation (0.5 M) was 12 mA g-1, which is 2.4 times better than that of Co3O4, whose mass activity is 5 mA g-1, and 4 times better than that of the CuO NS, whose mass activity is 3 mA g-1. The methanol oxidation peak at 0.62 V versus Ag/AgCl was also more intense than individual oxides. The trend in performance of methanol oxidation follows the order: Co3O4/CuO > Co3O4 > CuO. In the case of CO2 reduction, we experienced that our product was formate, and this was proved by formate oxidation (formate is formed as a product during the reduction of CO2) on the surface of the Pt ring of a rotating ring-disc electrode. Similar to methanol oxidation, Co3O4/CuO also showed superior activity in carbon dioxide reduction. It was experienced that at -1.5 V, the current density rises to -24 mA/cm2 for the Co3O4/CuO NS, that is, 0.6 times that of the CuO NS, which is -15 mA/cm2, and 3 times more than that of the Co3O4 NS, which is 8 mA/cm2. The trend in performance of CO2 reduction follows the order: Co3O4/CuO > CuO > Co3O4.

18.
J Colloid Interface Sci ; 578: 726-737, 2020 Oct 15.
Article in English | MEDLINE | ID: mdl-32574908

ABSTRACT

Herein we report a catalyst consisting of CuAg/Cu2O nanoparticles (NPs), synthesized on the two-dimensional carbon nitride (CN) surface via galvanic exchange route for electrocatalytic methanol oxidation and carbon dioxide reduction. The lower reduction potential of copper ([Cu+(aq) + e- â†’ Cu(s)], + 0.52 eV) compared to Ag ([Ag+(aq) + e- â†’ Ag(s)], +0.80 eV) makes Cu(0) easily exchangeable by Ag+ ions via galvanic exchange without applying any external bias. In a two-step process, the Cu NPs are synthesized first on CN surface by adsorbing Cu2+ precursors and reducing them by NaBH4. Due to unstable nature of Cu2+ in aqueous medium some Cu2O NPs (a mixed phase of Cu/CuO) were also formed. Thereafter in the second step, Ag+ precursors are brought in contact with the already synthesized Cu and Cu2O nanoparticles (NPs). The Cu and Cu2O NPs present on the surface of CN are partially exchanged by Ag atoms to generate bimetallic CuAg/Cu2O NPs. Two atoms of Ag are expected to be deposited for every Cu atom replaced. As galvanic replacement occurs on the solid surface of carbon nitride, there is only a partial replacement of Cu and Cu2O atoms. The catalysts CN/Cu/Cu2O and CN/CuAg/Cu2O were evaluated for their performance towards methanol oxidation and carbon dioxide reduction. CN/CuAg/Cu2O showed twice the current density for methanol oxidation than CN/Cu/Cu2O in a 0.5 M methanol solution. Probably the reason for high activity of Ag than Cu is related to the weak bond of oxygen on silver substrate for oxidation reactions and strong binding affinity on copper substrate. In case of carbon dioxide reduction (CO2 reduction) the product was identified to be formate by oxidizing the product (formate) on a Pt ring electrode. The results revealed CN/CuAg/Cu2O shows a better selectivity towards formic acid formation than CN/Cu/Cu2O using the rotating ring disc electrode (RRDE). A probable reason may be the strain induced by alloy formation which could favor a reduced coverage of adsorbed hydrogen and a decrease in oxophilicity of the compressively strained copper.

19.
Bioorg Chem ; 80: 472-479, 2018 10.
Article in English | MEDLINE | ID: mdl-29990895

ABSTRACT

A new series of N-acylhydrazone derivatives of 2-mercaptobenzimidazole (2-MBI) has been synthesized through S-alkylation with 1-bromotetradecane and N-alkylation with ethyl-2-chloroacetate. The resulting ester was synthetically modified through hydrazine hydrate to acyl hydrazide which was condensed with aromatic aldehydes to afford the title N-acylhydrazones (4-17). Chemical structures of the newly synthesized compounds have been confirmed through mass, FT-IR and 1HNMR techniques. In vitro free radical scavenging and α-glucosidase inhibition activities of the compounds were investigated with reference to the standard ascorbic acid and acarbose, respectively. Amongst the target compounds, 13 showed the highest inhibition in DPPH scavenging assay (IC50 = 131.50 µM) and α-glucosidase inhibition potential (IC50 = 352 µg/ml). We extended our investigations to explore the mechanism of enzyme inhibition and conducted docking analysis by using Molecular Operating Environment (MOE 2016.08). A homology model for α-glucosidase was constructed and validated using Ramachandran plot. Docking studies were also carried out on human intestinal α-glucosidases. In view of the importance of the nucleus involved, the synthesized compounds might find extensive medicinal applications as reported in the literature.


Subject(s)
Antioxidants/chemistry , Antioxidants/pharmacology , Benzimidazoles/chemistry , Benzimidazoles/pharmacology , Glycoside Hydrolase Inhibitors/chemistry , Glycoside Hydrolase Inhibitors/pharmacology , alpha-Glucosidases/metabolism , Acylation , Antioxidants/chemical synthesis , Benzimidazoles/chemical synthesis , Glycoside Hydrolase Inhibitors/chemical synthesis , Humans , Hydrazones/chemical synthesis , Hydrazones/chemistry , Hydrazones/pharmacology , Molecular Docking Simulation , Saccharomyces cerevisiae/enzymology , alpha-Glucosidases/chemistry
20.
J Sci Food Agric ; 97(13): 4408-4418, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28485471

ABSTRACT

BACKGROUND: Five maize inbred lines, 20 F1 diallel hybrids and two check genotypes were evaluated through genotype × environment interaction (GEI) and GGE biplot for earliness and yield traits at four locations. RESULTS: Genotype, environment and GEI showed highly significant differences for all the traits. In total sum of squares, environment and genotype played a primary role, followed by GEI. Larger effects of environment and genotype to total variation influence the earliness and yield traits. However, according to the GGE biplot, the first two principal components (PC1 and PC2) explained 95% of the variation caused by GEI. GGE biplot confirmed the differential response of genotypes across environments. F1 hybrid SWAJK-1 × FRHW-3 had better stability, with a good yield, and was considered an ideal genotype. F1 hybrid FRHW-2 × FRHW-1 showed more earliness at CCRI and Haripur, followed by PSEV3 × FRHW-2 and its reciprocal at Swat and Mansehra, respectively. F1 hybrids FRHW-1 × SWAJK-1, PSEV3 × SWAJK-1 and SWAJK-1 × FRHW-3 at Mansehra and Swat produced maximum grain yield, followed by SWAJK-1 × FRHW-1 and PSEV3 × FRHW-1 at Haripur and CCRI, respectively. CONCLUSION: Overall, maize genotypes showed early maturity in plain areas (CCRI and Haripur) but higher yield in hilly areas (Mansehra and Swat). © 2017 Society of Chemical Industry.


Subject(s)
Gene-Environment Interaction , Seeds/growth & development , Zea mays/growth & development , Zea mays/genetics , Climate , Ecosystem , Environment , Genotype , Phenotype , Seeds/chemistry , Seeds/genetics , Zea mays/chemistry
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