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1.
ChemMedChem ; : e202400236, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38934210

RESUMO

Intending to homogenize the biological activities of both quinoxaline and imidazole moieties, the proligand, 1-methyl-3-quinoxaline-imidazolium hexaflurophosphate (1.HPF6), and [Ag(1)2][PF6], (2); [Au(1)2][PF6], (3); and [Au(1)Cl3], (4) NHC complexes were synthesized. All the synthesized compounds were characterized by elemental analysis, NMR, and UV-Vis spectroscopy. Finally, single crystal X-ray structures revealed a linear geometry for complex 2 whereas a square planar geometry for complex 4. The formation of complex 3 was confirmed and supported by its MS spectra. The antibacterial activities of all the synthesized complexes were investigated against gram-positive bacteria and gram-negative bacteria. The Au(III)-NHC complex, 4 showed the highest antibacterial activity with extremely low MIC values against both the bacterial strains (0.24 µg.mL-1).  Monitoring of zeta potential supports the higher activity of complex 4 compared to 2 and 3. ROS production by complex 4 has also been measured in vitro in the CT26 cancer cell lines, which is directly responsible for targetting and killing the bacterial pathogens. Cell cytotoxicity assay using 293T cell lines has been performed to investigate the biocompatibility nature of complex 4. Also, an excellent hemocompatibility was assigned to it from its hemolytic studies,   which provide valuable insights into the design of novel antibacterial agents.

2.
Langmuir ; 40(26): 13476-13485, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38889432

RESUMO

Superlattice structures offer distinct benefits in modern semiconductor technology, enabling the development of a deeper understanding of their sublayer arising from the interfaces. However, the advancement of large-scale applications encounters additional concerns, such as the stability and performance of the superlattice. In this study, we employ density functional theory calculations combined with the Boltzmann transport theory to comprehensively analyze the electronic structural and transport properties of the hexagonal phase of WSe2 and the WSe2-WTe2 superlattice for their applications in carrier transport fields. Previous studies showed that longitudinal acoustics phonon limited carrier mobility determined by deformation potential theory (DPT) often compromises the accuracy and overestimates the relaxation time by 2 orders. Herein, we conduct an in-depth analysis of band structural and transport properties, addressing the aforementioned inconsistency by exclusively incorporating scattering from longitudinal optical phonons to accurately compute mobility using the Fröhlich interaction. Our findings reveal a significant enhancement in mobility for both electrons and holes in the WSe2-WTe2 superlattice, reaching 545 and 476 cm2 V-1 s-1, respectively, compared to 104 and 132 cm2 V-1 s-1 for WSe2, which suggests that this superlattice is a promising material for electronics and transport applications.

3.
Data Brief ; 54: 110547, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38882190

RESUMO

The draft genome sequence of an isolate of Bacillus safensis U41 from the soils of Santiniketan (23040'12″ N and 87039'52″ E) is reported here. Bacillus safensis is a bacterium that produces cellulases, which is essential for the breakdown of plant biomass. As such, it is a valuable source of digestive enzymes from plant biomass, especially cellulases. The genomic DNA was extracted from a single colony using a QIAgen Blood and Tissue kit (QIAgen Inc., Canada). Sequencing was performed via Illumina HiSeq X using 2 × 150 paired-end chemistry, generating 7,352,576 reads with sequence coverage of 509x. The assembly produced 20 contigs over 200 base pairs (bp) in length, with an N50 value of 901304 and an L50 of 2. The genome size was 3,732,407 bp, and the average GC content was 41.43 %. Genome annotation and gene predictions were performed using Prokka v.1.14.6, which identified 3783 coding sequences, 64 tRNA genes, and 3 rRNA genes.

4.
Arch Microbiol ; 206(4): 201, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38564030

RESUMO

Trimethylamine N-oxide (TMAO) is a gut metabolite that acts as a biomarker for chronic diseases, and is generated by the oxidation of trimethylamine (TMA) produced by gut microflora. Since, microbial degradation of TMA is predicted to be used to restrict the production of TMAO, we aimed to isolate bacterial strains that could effectively degrade TMA before being oxidized to TMAO. As marine fish is considered to have a rich content of TMAO, we have isolated TMA degrading isolates from fish skin. Out of the fourteen isolates, depending on their rapid TMA utilization capability in mineral salt medium supplemented with TMA as a sole carbon and nitrogen source, isolate PS1 was selected as our desired isolate. Its TMA degrading capacity was further confirmed through spectrophotometric, Electrospray Ionization Time-of-Flight Mass Spectrometry (ESI TOF-MS) and High performance liquid chromatography (HPLC) analysis and in silico analysis of whole genome (WG) gave further insights of protein into its TMA degradation pathways. PS1 was taxonomically identified as Paracoccus sp. based on its 16S rRNA and whole genome sequence analysis. As PS1 possesses the enzymes required for degradation of TMA, clinical use of this isolate has the potential to reduce TMAO generation in the human gut.


Assuntos
Genômica , Metilaminas , Paracoccus , Animais , Humanos , RNA Ribossômico 16S/genética , Paracoccus/genética
5.
Phys Chem Chem Phys ; 26(12): 9340-9349, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38444311

RESUMO

Designing an n-type thermoelectric material with a high thermoelectric figure of merit at near room temperature is extremely challenging. Generally, pristine Ag2Se reveals unusually low thermal conductivity along with a high electrical conductivity and Seebeck coefficient, which leads to high thermoelectric performance (n-type) at room temperature. Herein, we report a pseudo-ternary phase (Ag2Se0.5Te0.25S0.25) that exhibits significantly high thermoelectric performance (zT ∼ 2.1) even at 400 K. First-principles calculation reveals that the Rashba type of spin-dependent band spitting, which originates due to sulfur and tellurium substitution, helps to improve the thermopower magnitude. We also show that the intrinsic carrier mobility is not only controlled by the carrier effective mass but is substantially limited by longitudinal acoustic and optical phonon modes, which is an extension of the deformation potential theory. Locally off-center sulfur atoms, together with the increase in configurational entropy via substitution of Te and S atoms in Ag2Se, lead to a drastic reduction in the lattice thermal conductivity (klat ∼ 0.34 W m-1 K-1 at 400 K). The Rashba effect coupled with the configurational entropy synergistically results in a high thermoelectric figure of merit in the n-type thermoelectric material working in the near-room-temperature regime.

6.
Dalton Trans ; 52(43): 15896-15906, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37840479

RESUMO

A polypyridyl-imidazole-based bridging ligand, 2-(4-(4,5-di(pyridine-2-yl)-1H-imidazole-2-yl)phenyl)-1H-imidazo[4,5-f][1,10]phenanthroline (phen-H2PhImz-bpy), possessing three bidentate coordinating sites, has been designed in this work. The bridging ligand is employed to synthesize mono-, bi-, and trimetallic Ru(II) complexes in combination with terminal bipyridine units for the systematic modulation of photophysical and redox properties upon sequential incorporation of the metal unit into the bridge. All the compounds are characterized via NMR spectroscopy and electrospray ionization mass spectrometry. Absorption and both steady-state and time-resolved emission spectroscopic investigations of the ligand as well as Ru(II) complexes are thoroughly conducted in different solvents. The redox behaviors of the complexes are examined through cyclic voltammetry (CV) in acetonitrile. The focus of the investigation is centered on the systematic modulation of MLCT absorption and emission as well as the redox behavior of the complex entity upon the gradual incorporation of the Ru2+ unit into the complex backbone. The emission energy, quantum yield and lifetime are found to decrease systematically with an increase in the Ru2+ unit in the complex backbone and a linear relationship is observed in each case. A good correlation is also observed between the emission energies of complexes with their respective ΔE1/2 values (the difference between the first oxidation and first reduction potential).

7.
ACS Omega ; 8(22): 19625-19631, 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37305253

RESUMO

The design and synthesis of a cleft-shaped bis-diarylurea receptor for chloride anion transport is reported in this work. The receptor is based on the foldameric nature of N,N'-diphenylurea upon its dimethylation. The bis-diarylurea receptor exhibits a strong and selective affinity for chloride over bromide and iodide anions. A nanomolar quantity of the receptor efficiently transports the chloride across a lipid bilayer membrane as a 1:1 complex (EC50 = 5.23 nm). The work demonstrates the utility of the N,N'-dimethyl-N,N'-diphenylurea scaffold in anion recognition and transport.

8.
Compend Contin Educ Dent ; 44(2): e1-e4, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36787577

RESUMO

Scientists throughout the world have been intrigued by the concept of hypnopedia or sleep learning. This concept was initially thought to be useful in learning new languages when heard during sleep. While having been in and out of favor with researchers over the years, recent evidence has supported the possibility that hypnopedia can actually take place. Although researchers propose that no one simply can learn new facts and figures in sleep without first being aware of them, the concept of targeted memory reactivation might help to reinforce things that an individual might learn when asleep. Evidence suggests that subtle sounds presented during sleep, such as repetitive statements and encouraging words, can strengthen memory processing. This concept may be useful in pediatric dentistry in an effort to help children, especially uncooperative ones, improve their behavior while being administered dental treatment.


Assuntos
Aprendizagem , Odontopediatria , Sono , Criança , Humanos , Sono/fisiologia , Som
9.
ACS Infect Dis ; 9(1): 162-177, 2023 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-36417798

RESUMO

Leishmaniasis is a group of neglected tropical diseases (NTDs) caused by about 20 species of obligate intracellular protozoan parasites of the genus Leishmania, which occurs in cutaneous, mucocutaneous, and visceral forms. Many researchers have sought to utilize natural products for novel and effective treatments to combat many infectious diseases, including leishmaniasis. Holarrhena pubescens Wall. ex G. Don (Apocynaceae) bark is a rich source of bioactive steroidal alkaloids. The total alkaloidal extract (IC50 6.12 ± 0.117 µg/mL), and the isolated alkaloid, holanamine, showed significant antileishmanial activity (IC50 2.66 ± 0.112 µM against AG83 and 3.80 ± 0.126 µM against BHU-575) against the Leishmania donovani parasite, better than miltefosine (IC50 19.61 ± 0.093 µM against AG83 and 23.20 ± 0.094 µM against BHU-575). Holanamine inhibited the L. donovani topoisomerase 1B (LdToP1B) in a non-competitive manner (IC50 2.81 ± 0.105 µM), indicating that it interacts with the free enzyme and enzyme-DNA complex without inhibiting human topoisomerase. Hydrogen bonding and hydrophobic interactions of holanamine with the N-terminal and hinge region of the large subunit of LTop1B is responsible for its potent antileishmanial activity, as shown by docking studies. Treatment with holanamine causes apoptotic-like cell death by generating cellular and mitochondrial reactive oxygen species, disrupting the mitochondrial membrane potential and inducing ultrastructural alterations in the promastigotes. Holanamine effectively clears intracellular amastigotes but minimally affects host macrophages with no significant cytotoxicity in HEK 293 and L929 cell lines. Thus, our studies show that holanamine can further be used to develop effective antileishmanial agents against evolving drug-resistant parasites.


Assuntos
Alcaloides , Antineoplásicos , Holarrhena , Leishmania donovani , Casca de Planta , Humanos , Alcaloides/farmacologia , Antineoplásicos/farmacologia , DNA Topoisomerases Tipo I/química , DNA Topoisomerases Tipo I/metabolismo , Células HEK293 , Holarrhena/metabolismo , Casca de Planta/química , Casca de Planta/metabolismo
10.
Int J Clin Pediatr Dent ; 15(3): 293-298, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35991784

RESUMO

Introduction: Pediatric dentists often see a good number of children under 6 years of age and are likely to encounter a child with missing anterior teeth. Here the parents are more concerned about the facial esthetics of the child and also about the timing of permanent teeth to erupt. Aim: To know the impact on self-esteem or body image of preschool children following the premature loss of primary anterior teeth. Materials and methods: The present cross-sectional study was conducted among 780 children in the age group of 4-6 years. The COHIP-SF 19 was utilized to know the social well-being of the child following the premature loss of anterior teeth. The descriptive and inferential analysis of the data was done by using IBM SPSS software. Results: There was a statistically significant association between gender and social well-being. More number of boys were concerned about their looks (p = 0.054). However, girls were found to be significantly more (p = 0.003) shy or withdrawn as compared to boys. There was a statistically significant association between a child's age and social well-being. More number of children between the ages of 4 years (23.1%) and 6 years (25.8%) were worried or anxious due to premature loss of an anterior tooth. Significantly more no of children of age 5 years (48.6%) was uncomfortable when asked about the missing tooth as compared to 4- and 6-year-old children. No statistically significant (p > 0.05) difference in the mean social well-being scores between boys and girls. No statistically significant difference in the mean social well-being scores between children of ages 4, 5, and 6 years (p > 0.05). Conclusion: There is an association between the self-image of younger children and missing anterior teeth. How to cite this article: Acharya S, Biswas R. Body Image in Preschool Children Following Premature Loss of Primary Teeth: A Cross-sectional Study. Int J Clin Pediatr Dent 2022;15(3):293-298.

11.
J Phys Chem Lett ; 13(24): 5431-5440, 2022 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-35679509

RESUMO

Manipulation of intrinsic carrier relaxation is crucial for designing efficient lead halide perovskite nanocrystal (NC) based optoelectronic devices. The influence of heterovalent Bi3+ doping on the ultrafast carrier dynamics and hot carrier (HC) cooling relaxation of CsPbBr3 NCs has been studied using femtosecond transient absorption spectroscopy and first-principles calculations. The initial HC temperature and LO phonon decay time point to a faster HC relaxation rate in the Bi3+-doped CsPbBr3 NCs. The first-principles calculations disclose the acceleration of carrier relaxation in Bi3+-doped CsPbBr3 NCs due to the appearance of localized bands (antitrap states) within the conduction band. The higher Born effective charges (Z*) and higher soft energetic optical phonon density of states cause higher electron-phonon scattering rates in the Bi-doped CsPbBr3 system, which is responsible for the faster HC cooling rate in doped systems.

12.
Sci Rep ; 12(1): 8439, 2022 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-35589928

RESUMO

Contamination of soil by antibiotics and heavy metals originating from hospital facilities has emerged as a major cause for the development of resistant microbes. We collected soil samples surrounding a hospital effluent and measured the resistance of bacterial isolates against multiple antibiotics and heavy metals. One strain BMCSI 3 was found to be sensitive to all tested antibiotics. However, it was resistant to many heavy metals and metalloids like cadmium, chromium, copper, mercury, arsenic, and others. This strain was motile and potentially spore-forming. Whole-genome shotgun assembly of BMCSI 3 produced 4.95 Mb genome with 4,638 protein-coding genes. The taxonomic and phylogenetic analysis revealed it, to be a Bordetella petrii strain. Multiple genomic islands carrying mobile genetic elements; coding for heavy metal resistant genes, response regulators or transcription factors, transporters, and multi-drug efflux pumps were identified from the genome. A comparative genomic analysis of BMCSI 3 with annotated genomes of other free-living B. petrii revealed the presence of multiple transposable elements and several genes involved in stress response and metabolism. This study provides insights into how genomic reorganization and plasticity results in evolution of heavy metals resistance by acquiring genes from its natural environment.


Assuntos
Metais Pesados , Solo , Antibacterianos , Bordetella , Genômica , Hospitais , Metais Pesados/toxicidade , Filogenia
13.
Curr Microbiol ; 79(5): 131, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35290506

RESUMO

Arsenic contaminations, often adversely influencing the living organisms, including plants, animals, and the microbial communities, are of grave apprehension. Many physical, chemical, and biological techniques are now being explored to minimize the adverse affects of arsenic toxicity. Bioremediation of arsenic species using arsenic loving bacteria has drawn much attention. Arsenate and arsenite are mostly uptaken by bacteria through aquaglycoporins and phosphate transporters. After entering arsenic inside bacterial cell arsenic get metabolized (e.g., reduction, oxidation, methylation, etc.) into different forms. Arsenite is sequentially methylated into monomethyl arsenic acid (MMA) and dimethyl arsenic acid (DMA), followed by a transformation of less toxic, volatile trimethyl arsenic acid (TMA). Passive remediation techniques, including adsorption, biomineralization, bioaccumulation, bioleaching, and so on are exploited by bacteria. Rhizospheric bacterial association with some specific plants enhances phytoextraction process. Arsenic-resistant rhizospheric bacteria have immense role in enhancement of crop plant growth and development, but their applications are not well studied till date. Emerging techniques like phytosuction separation (PS-S) have a promising future, but still light to be focused on these techniques. Plant-associated bioremediation processes like phytoextraction and phytosuction separation (PS-S) techniques might be modified by treating with potent bacteria for furtherance.


Assuntos
Arsênio , Animais , Arsênio/metabolismo , Bactérias/genética , Bactérias/metabolismo , Biodegradação Ambiental , Metilação , Oxirredução
14.
J. Phys. Educ. (Maringá) ; 33: e3334, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1385998

RESUMO

ABSTRACT The aim of the present study was to find out the effect of varied plyometric training (land plyometric training, aqua plyometric training and weighted vest aqua-plyometric training) on anaerobic power of school athletes. A total of forty eight (n= 48) district level school athletes were randomly selected. All the subjects were divided into four equal groups: i) land plyometric training group (n=12), ii) aqua plyometric training group (n=12), iii) aqua-plyometric training with weighted vest group (n=12) and iv) control group (n=12). The varied plyometric training was intervened for fourteen weeks in the respective training groups. In the present study, anaerobic power was considered as the dependent variable, and it was measured by Margaria-Kalamen power test. To draw statistical inferences on anaerobic power among the groups in pre and post intervention conditions, ANCOVA was used, followed by Tukey's LSD post-hoc test. The significance of the means was tested at the 0.05 level. Different plyometric training groups improved significantly with respect to the control group in anaerobic power. Therefore, various plyometric training was found as an effective means for developing anaerobic power. A significant difference was also observed between the aqua-plyometric training with weighted vest group and land plyometric training group in anaerobic power. However, rest of the experimental groups didn't differ significantly. Aqua-plyometric training with weighted vest is a more effective training method than land plyometric training for improving the anaerobic power of the school athletes.


RESUMO O objetivo do presente estudo foi descobrir o efeito do treinamento pliométrico variado (treinamento pliométrico terrestre, treinamento aquapliométrico e treinamento aquapliométrico com colete ponderado) na potência anaeróbica de atletas escolares. Um total de quarenta e oito (n= 48) atletas escolares de nível distrital foram selecionados aleatoriamente. Todos os sujeitos foram divididos em quatro grupos iguais: i) grupo treinamento pliométrico terrestre (n=12), ii) grupo treinamento aquapliométrico (n=12), iii) grupo treinamento aquapliométrico com colete ponderado (n=12) e iv) grupo controle (n=12). O treino pliométrico variado foi intervencionado durante quatorze semanas nos respectivos grupos de treino. No presente estudo, a potência anaeróbia foi considerada como variável dependente e foi mensurada pelo teste de potência de Margaria-Kalamen. Para fazer inferências estatísticas sobre a potência anaeróbica entre os grupos nas condições pré e pós-intervenção, foi utilizada a ANCOVA, seguida do teste post-hoc de Tukey LSD. A significância das médias foi testada no nível 0,05. Diferentes grupos de treinamento pliométrico melhoraram significativamente em relação ao grupo controle na potência anaeróbica. Portanto, vários treinamentos pliométricos foram encontrados como um meio eficaz para o desenvolvimento da potência anaeróbica. Uma diferença significativa também foi observada entre o grupo de treinamento aquapliométrico com colete ponderado e o grupo de treinamento pliométrico terrestre na potência anaeróbica. No entanto, o resto dos grupos experimentais não diferiram significativamente. O treinamento aquapliométrico com colete ponderado é um método de treinamento mais eficaz do que o treinamento pliométrico terrestre para melhorar a potência anaeróbica dos atletas escolares.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adolescente , Atletas/educação , Exercício Pliométrico/métodos , Educação Física e Treinamento/métodos , Exercício Físico , Tutoria/métodos , Esportes Aquáticos/educação , Treino Aeróbico/métodos
15.
Arch Microbiol ; 203(6): 2761-2770, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33811263

RESUMO

Environmental health is a critical concern, continuously contaminated by physical and biological components (viz., anthropogenic activity), which adversely affect on biodiversity, ecosystems and human health. Nonetheless, environmental pollution has great impact on microbial communities, especially bacteria, which try to evolve in changing environment. For instance, during the course of adaptation, bacteria easily become resistance to antibiotics and heavy metals. Antibiotic resistance genes are now one of the most vital pollutants, provided as a source of frequent horizontal gene transfer. In this review, the environmental cause of multidrug resistance (MDR) that was supposed to be driven by either heavy metals or combination of environmental factors was essentially reviewed, especially focussed on the correlation between accumulation of heavy metals and development of MDR by bacteria. This kind of correlation was seemed to be non-significant, i.e. paradoxical. Gram-positive bacteria accumulating much of toxic heavy metal (i.e. highly stress tolerance) were unlikely to become MDR, whereas Gram-negative bacteria that often avoid accumulation of toxic heavy metal by efflux pump systems were come out to be more prone to MDR. So far, other than antibiotic contaminant, no such available data strongly support the direct influence of heavy metals in bacterial evolution of MDR; combinations of factors may drive the evolution of antibiotic resistance. Therefore, Gram-positive bacteria are most likely to be an efficient member in treatment of industrial waste water, especially in the removal of heavy metals, perhaps inducing the less chance of antibiotic resistance pollution in the environment.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Metais Pesados/toxicidade , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Humanos , Metais Pesados/metabolismo
16.
Curr Gene Ther ; 21(3): 207-215, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33390136

RESUMO

Cancer therapy describes the treatment of cancer, often with surgery, chemotherapy, and radiotherapy. Additionally, RNA interference (RNAi) is likely to be considered a new emerging, alternative therapeutic approach for silencing/targeting cancer-related genes. RNAi can exert antiproliferative and proapoptotic effects by targeting functional carcinogenic molecules or knocking down gene products of cancer-related genes. However, in contrast to conventional cancer therapies, RNAi based therapy seems to have fewer side effects. Transcription signal sequence and conserved sequence analysis-showed that microorganisms could be a potent source of non-coding RNAs. This review concluded that mapping of RNAi mechanism and RNAi based drug delivery approaches is expected to lead a better prospective of cancer therapy.


Assuntos
Sistemas de Liberação de Medicamentos , Neoplasias/genética , Neoplasias/terapia , Interferência de RNA , RNA não Traduzido/genética , RNA não Traduzido/uso terapêutico , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Inativação Gênica , Humanos
17.
ACS Omega ; 5(45): 29009-29016, 2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-33225132

RESUMO

Despite several oxides with trivalent cobalt ions are known, the sesquioxide M2O3 with Co3+ ions remains elusive. Our attempts to prepare Co2O3 have failed. However, 50% of Co3+ ions could be substituted for Ln3+ ions in Ln2O3 (Ln = Y and Lu) with a cubic bixbyite structure where the Co3+ ions are in the intermediate-spin state. We have therefore examined the structural stability of Co2O3 and the special features of solid solutions (Ln0.5Co0.5)2O3 (Ln = Y and Lu). The experimental results are interpreted in the context of ab initio-based density functional theory, molecular dynamics (AIMD), and crystal orbital Hamiltonian population (COHP) analysis. Our AIMD study signifies that Co2O3 in a corundum structure is not stable. COHP analysis shows that there is instability in Co2O3 structures, whereas Co and O have a predominantly bonding character in the bixbyite structure of the solid solution (Y0.5Co0.5)2O3.

18.
Extremophiles ; 24(6): 875-885, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32955600

RESUMO

Inland athalassohaline solar salterns provide unique opportunity to study microbial successions along salinity gradients that resemble transition in natural hypersaline lakes. We analyzed for the first time 16S rRNA gene amplicon sequences of bacteria (V1-V2) and archaea (V4-V5) in saltern brines of India's largest inland hypersaline Sambhar Lake. Brines of the salterns (S1-S4) are alkaline (pH 9.5-10.5) with salinities of 130, 170, 280 and 350 gL-1 respectively. 16S rRNA gene copy-number of archaea outnumbered that of bacteria in all salterns. Their diversity also increased along S1 through S4, while that of bacteria decreased. Brines of S3 and S4 were dominated by specialized extreme halophilic bacterial (Halanaerobiales, Rhodothermaceae) and archaeal (Halobacteriales, Haloferacales) members with recognized salt-in strategy for osmoadaptation. Microbial assemblages positively correlated to saltern pH, total salinity, and ionic composition. Archaea in S1 and S2 were unprecedentedly represented by poorly known as-yet uncultivated groups, Woesearchaeota (90.35-93.51%) and Nanohaloarchaeota that belong to the newly proposed nano-sized superphylum DPANN. In fact, these taxa were identified in archaeal datasets of other athalassohaline salterns after re-analysis using latest RDP database. Thus, microbial compositions in hypersaline lakes are complex and need revisit particularly for their archaeal diversity to understand their hitherto unknown ecological function in extreme environments.


Assuntos
Lagos/microbiologia , Microbiota , Filogenia , Águas Salinas , Archaea/classificação , Bactérias/classificação , Índia , RNA Ribossômico 16S/genética , Salinidade
19.
J Korean Assoc Oral Maxillofac Surg ; 46(3): 183-190, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32606279

RESUMO

OBJECTIVES: The purpose of this retrospective epidemiological study was to determine the etiology and pattern of maxillofacial injuries in a pediatric population. MATERIALS AND METHODS: Data for pediatric maxillofacial trauma patients aged 12 years and younger who were registered at the Department of Pediatric and Preventive Dentistry, Dr. R. Ahmed Dental College and Hospital, Kolkata, India, were reviewed and examined. Patients who were treated between October 2016 and September 2018 were analyzed according to age, sex, cause of injury, frequency and site of facial fractures, and soft tissue injuries. The chi-square tests were carried out for statistical analyses with a significance level of 5%. RESULTS: Of 232 patients with a mean age of 6.77±3.25 years, there were 134 males (57.8%) and 98 females (42.2%). The overall male to female ratio was 1.39:1. The most common causes of injuries were falls (56.5%) and motor vehicle accidents (16.8%). Incidence of falls decreased significantly with age (P<0.001). Dentoalveolar injuries (61.6%) and soft tissue injuries (57.3%) were more common than facial fractures (42.7%). Mandibular fractures (82.8%) were the most common facial fractures, and perioral or lip injuries were the most prevalent injuries in our patient population. There was a positive association between facial fractures and soft tissue injury (P<0.01) (odds ratio 0.26; confidence interval 0.15-0.46). CONCLUSION: Falls were the leading cause of maxillofacial trauma in our sample of children, and the most common site of fractures was the mandible.

20.
Evol Bioinform Online ; 15: 1176934319834888, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31223230

RESUMO

INTRODUCTION: DNA barcode, a molecular marker, is used to distinguish among the closely related species, and it can be applied across a broad range of taxa to understand ecology and evolution. MaturaseK gene (matK) and rubisco bisphosphate carboxylase/oxygenase form I gene (rbcL) of the chloroplast are highly conserved in a plant system, which are used as core barcode. This present endeavor entails the comprehensive examination of the under threat plant species based on success of discrimination on DNA barcode under selection pressure. RESULT: The family Dipterocarpaceae comprising of 15 genera is under threat due to some factors, namely, deforestation, habitat alteration, poor seed, pollen dispersal, etc. Species of this family was grouped into 6 clusters for matK and 5 clusters and 2 sub-clusters for rbcL in the phylogenetic tree by using neighbor-joining method. Cluster I to cluster VI of matK and cluster I to cluster V of rbcL genes were analyzed by various codon and substitution bias tools. Mutational pressure guided the codon bias which was favored by the avoidance of higher GC content and significant negative correlation between GC12 and GC3 (in sub-cluster I of cluster I [0.03 < P], cluster I [0.00001 < P], and cluster II [0.01 < P] of rbcL, and cluster IV [0.013 < P] of matK). After refining the results, it could be speculated that the lower null expectation values (R = 0.5 or <0.5) were less divergent from the evolutionary perspective. Apart from that, the higher null expectation values (R = >0.85) also showed the same result, which possibly could be due to the negative impact of very high and low transition rate than transversion. CONCLUSION: Through the analysis of inter-generic, inter/intra-specific variation and phylogenetic data, it was found that both selection and mutation played an important role in synonymous codon choice in these genes, but they acted inconsistently on the genes, both matK and rbcL. In vitro stable proteins of both matK and rbcL were selected through natural selection rather than mutational selection. matK gene had higher individual discrimination and barcode success compared with rbcL. These discriminatory approaches may describe the problem related to the extinction of plant species. Hence, it becomes very imperative to identify and detect the under threat plant species in advance.

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