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1.
Mikrochim Acta ; 191(7): 373, 2024 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-38842697

RESUMO

The design of surface plasmon resonance (SPR) sensors has been greatly enhanced in recent years by the advancements in the production and integration of nanostructures, leading to more compact and efficient devices. There have been reports of novel SPR sensors having distinct nanostructures, either as signal amplification tags like gold nanoparticles (AuNPs) or as sensing substrate-like two-dimensional (2D) materials including graphene, transition metal dichalcogenides (TMDCs), MXene, black phosphorus (BP), metal-organic frameworks (MOFs), and antimonene. Such 2D-based SPR biosensors offer advantages over conventional sensors due to significant increases in their sensitivity with a good figure of merit and limit of detection (LOD). Due to their atomically thin structure, improved sensitivity, and sophisticated functionalization capabilities, 2D materials can open up new possibilities in the field of healthcare, particularly in point-of-care diagnostics, environmental and food monitoring, homeland security protection, clinical diagnosis and treatment, and flexible or transient bioelectronics. The present study articulates an in-depth analysis of the most recent developments in 2D material-based SPR sensor technology. Moreover, in-depth research of 2D materials, their integration with optoelectronic technology for a new sensing platform, and the predicted and experimental outcomes of various excitation approaches are highlighted, along with the principles of SPR biosensors. Furthermore, the review projects the potential prospects and future trends of these emerging materials-based SPR biosensors to advance in clinical diagnosis, healthcare biochemical, and biological applications.


Assuntos
Ressonância de Plasmônio de Superfície , Técnicas Biossensoriais/métodos , Ouro/química , Grafite/química , Limite de Detecção , Nanopartículas Metálicas/química , Estruturas Metalorgânicas/química , Nanoestruturas/química , Fósforo/química , Ressonância de Plasmônio de Superfície/métodos
2.
Cryo Letters ; 45(3): 168-176, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38709188

RESUMO

BACKGROUND: Antioxidants minimise oxidative stress and enhance sperm quality in the process of cryopreservation. OBJECTIVE: To assess the impact of Cinnamomum zeylanicum extract as an additive during the post-dilution and post-thaw stages of Murrah buffalo semen cryopreservation. MATERIALS AND METHODS: The semen sample was diluted using Tris-Egg-Yolk-Citric-Acid-Fructose-Glycerol extender and subsequently divided into three groups: Group 1, TEYCAFG without any additives or controls (C); Group 2, TEYCAFG fortified with a 50 ug/mL aqueous extract of cinnamon (T1); and Group 3, TEYCAFG fortified with a 50 ug/mL ethanolic extract of cinnamon (T2). The evaluation included an assessment of progressive motility, live spermatozoa, sperm abnormalities, HOST, CMPT, and enzyme leakage (GOT and GPT) at both the post-dilution and post-thaw stages. RESULTS: The groups that received cinnamon supplementation demonstrated statistically significant improvements (p<0.05) in various parameters, including an increase in the progressive motility, live spermatozoa, and HOS-positive spermatozoa, as well as greater distance traveled by vanguard spermatozoa compared to the control group. Furthermore, the cinnamon-added groups exhibited a significant decrease (p<0.05) in the percentage of sperm abnormalities and lower enzyme leakage (GOT and GPT) in post-thawed semen. CONCLUSION: Aqueous extract of C. zeylanicum at a concentration of 50 µg/mL provides superior protection of sperm structures and functions as compared to both the ethanolic extract of C. zeylanicum at the same concentration and the control group. Doi.org/10.54680/fr24310110712.


Assuntos
Antioxidantes , Búfalos , Criopreservação , Extratos Vegetais , Sêmen , Masculino , Animais , Sêmen/citologia , Sêmen/metabolismo , Criopreservação/veterinária , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Trealose/farmacologia , Antioxidantes/farmacologia , Preservação da Fertilidade/veterinária
3.
Am J Physiol Heart Circ Physiol ; 325(6): H1446-H1460, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37889254

RESUMO

Epidemiological evidence shows that residential proximity to greenspaces is associated with lower risk of all-cause and cardiovascular mortality; however, the mechanism(s) underlying this link remains unclear. Plants emit biogenic volatile organic compounds such as α-pinene that could elicit beneficial cardiovascular effects. To explore the role of α-pinene more directly, we studied the metabolism and the vascular effects of α-pinene. We found that exposure of mice to α-pinene (1 ppm, 6 h) generated two phase I oxidation metabolites, cis- and trans-verbenol [(1R,2R,5R)-verbenol and (1 R,2S,5R)-verbenol)] and myrtenol [(1S,5R)-(+)-myrtenol] that were identified in urine by GC-MS. Precontracted naïve murine male and female aorta and superior mesenteric artery (SMA) were relaxed robustly (60% tension reduction) by increasing concentrations of α-pinene, myrtenol, and verbenol to 0.3 mM, whereas 1 mM α-pinene was vasotoxic. The SMA was six times more sensitive than the aorta to α-pinene. Both myrtenol and verbenol were equally potent and efficacious as parent α-pinene in male and female SMA. The sensitive portion of the α-pinene-, myrtenol-, and verbenol-induced relaxations in male SMA was mediated by 1) endothelium, 2) eNOS-derived NO, and 3) guanylyl cyclase (GC) activity. Moreover, α-pinene activated the transient receptor potential ankyrin-1 (TRPA1) channel whereas the metabolites did not. Endothelial-derived NO regulates blood flow, blood pressure, and thrombosis, and it is plausible that inhaled (and ingested) α-pinene (or its metabolites) augments NO release to mediate the cardiovascular benefits of exposure to greenness.NEW & NOTEWORTHY A common plant-derived biogenic volatile organic compound, α-pinene, and two of its metabolites, myrtenol and verbenol, stimulate vasorelaxation in murine superior mesenteric artery. Both α-pinene- and its metabolites induce vasorelaxation by activation of the endothelium, nitric oxide, and guanylyl cyclase. α-Pinene also activates the transient receptor potential ankyrin-1. Positive associations between greenness exposure and human cardiovascular health may be a result of the vascular action of α-pinene and its metabolites, a novel consideration.


Assuntos
Anquirinas , Monoterpenos , Humanos , Animais , Camundongos , Monoterpenos/farmacologia , Monoterpenos/metabolismo , Endotélio/metabolismo , Guanilato Ciclase
4.
Ultrasound Obstet Gynecol ; 62(1): 148-151, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36806323

RESUMO

Anti-Ro/SSA-antibody-mediated endocardial fibroelastosis (EFE) without atrioventricular (AV) block at presentation is a rare cardiac phenotype. We report on 11 fetuses with this rare type of anti-Ro/SSA-antibody-mediated cardiac involvement, presenting with a distinctive echocardiographic pattern of EFE. Eleven fetuses with isolated EFE at presentation were included from four cardiac centers, and experienced fetal cardiologists reached a consensus regarding EFE location on echocardiography at presentation. Interval changes to subsequent fetal and postnatal echocardiograms were assessed to evaluate response to therapy. Echocardiographic markers of cardiac performance, including diastolic function and AV conduction, were reviewed. Ten fetuses were found to have EFE of the aortic root, proximal aorta and/or left ventricular outflow tract. In the same 10 cases, EFE of the pulmonary root, pulmonary artery and/or right ventricular outflow tract was identified. Six cases had atrial EFE and six had EFE of the crux. Four cases were known to be positive for anti-Ro/SSA antibodies prior to diagnosis, whereas, in the remaining seven, echocardiographic findings prompted testing, which was positive in all cases. The AV interval at presentation was normal in all cases, but one fetus subsequently developed AV block. Nine patients were treated with transplacental dexamethasone, five of which also received intravenous immunoglobulin (IVIG), and one received IVIG only. Of the 10 treated cases, six had improvement in EFE as shown by serial imaging and, in four cases, the severity was unchanged. All patients were liveborn. In our cohort, EFE of the aortic and pulmonary arteries and outflow tracts was nearly universal, and involvement of the atria and the crux of the heart was also common. The high survival rate and low burden of AV block are also suggestive of a distinct phenotype of anti-Ro/SSA-antibody-mediated cardiac disease with a favorable prognosis. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Bloqueio Atrioventricular , Fibroelastose Endocárdica , Gravidez , Feminino , Humanos , Imunoglobulinas Intravenosas , Feto , Fibroelastose Endocárdica/diagnóstico por imagem , Ecocardiografia/métodos
5.
Stud Mycol ; 106: 259-348, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38298569

RESUMO

Many members of the Oomycota genus Phytophthora cause economic and environmental impact diseases in nurseries, horticulture, forest, and natural ecosystems and many are of regulatory concern around the world. At present, there are 223 described species, including eight unculturable and three lost species. Twenty-eight species need to be redescribed or validated. A lectotype, epitype or neotype was selected for 20 species, and a redescription based on the morphological/molecular characters and phylogenetic placement is provided. In addition, the names of five species are validated: P. cajani, P. honggalleglyana (Synonym: P. hydropathica), P. megakarya, P. pisi and P. pseudopolonica for which morphology and phylogeny are given. Two species, P. ×multiformis and P. uniformis are presented as new combinations. Phytophthora palmivora is treated with a representative strain as both lecto- and epitypification are pending. This manuscript provides the updated multigene phylogeny and molecular toolbox with seven genes (ITS rDNA, ß-tub, COI, EF1α, HSP90, L10, and YPT1) generated from the type specimens of 212 validly published, and culturable species (including nine hybrid taxa). The genome information of 23 types published to date is also included. Several aspects of the taxonomic revision and phylogenetic re-evaluation of the genus including species concepts, concept and position of the phylogenetic clades recognized within Phytophthora are discussed. Some of the contents of this manuscript, including factsheets for the 212 species, are associated with the "IDphy: molecular and morphological identification of Phytophthora based on the types" online resource (https://idtools.org/tools/1056/index.cfm). The first version of the IDphy online resource released to the public in September 2019 contained 161 species. In conjunction with this publication, we are updating the IDphy online resource to version 2 to include the 51 species recently described. The current status of the 223 described species is provided along with information on type specimens with details of the host (substrate), location, year of collection and publications. Additional information is provided regarding the ex-type culture(s) for the 212 valid culturable species and the diagnostic molecular toolbox with seven genes that includes the two metabarcoding genes (ITS and COI) that are important for Sanger sequencing and also very valuable Molecular Operational Taxonomic Units (MOTU) for second and third generation metabarcoding High-throughput sequencing (HTS) technologies. The IDphy online resource will continue to be updated annually to include new descriptions. This manuscript in conjunction with IDphy represents a monographic study and the most updated revision of the taxonomy and phylogeny of Phytophthora, widely considered one of the most important genera of plant pathogens. Taxonomic novelties: New species: Phytophthora cajani K.S. Amin, Baldev & F.J. Williams ex Abad, Phytophthora honggalleglyana Abad, Phytophthora megakarya Brasier & M.J. Griffin ex Abad, Phytophthora pisi Heyman ex Abad, Phytophthora pseudopolonica W.W. Li, W.X. Huai & W.X. Zhao ex Abad & Kasiborski; New combinations: Phytophthora ×multiformis (Brasier & S.A. Kirk) Abad, Phytophthora uniformis (Brasier & S.A. Kirk) Abad; Epitypifications (basionyms): Peronospora cactorum Lebert & Cohn, Pythiacystis citrophthora R.E. Sm. & E.H. Sm., Phytophthora colocasiae Racib., Phytophthora drechsleri Tucker, Phytophthora erythroseptica Pethybr., Phytophthora fragariae Hickman, Phytophthora hibernalis Carne, Phytophthora ilicis Buddenh. & Roy A. Young, Phytophthora inundata Brasier et al., Phytophthora megasperma Drechsler, Phytophthora mexicana Hotson & Hartge, Phytophthora nicotianae Breda de Haan, Phytophthora phaseoli Thaxt., Phytophthora porri Foister, Phytophthora primulae J.A. Toml., Phytophthora sojae Kaufm. & Gerd., Phytophthora vignae Purss, Pythiomorpha gonapodyides H.E. Petersen; Lectotypifications (basionym): Peronospora cactorum Lebert & Cohn, Pythiacystis citrophthora R.E. Sm. & E.H. Sm., Phytophthora colocasiae Racib., Phytophthora drechsleri Tucker, Phytophthora erythroseptica Pethybr., Phytophthora fragariae Hickman, Phytophthora hibernalis Carne, Phytophthora ilicis Buddenh. & Roy A. Young, Phytophthora megasperma Drechsler, Phytophthora mexicana Hotson & Hartge, Phytophthora nicotianae Breda de Haan, Phytophthora phaseoli Thaxt., Phytophthora porri Foister, Phytophthora primulae J.A. Toml., Phytophthora sojae Kaufm. & Gerd., Phytophthora vignae Purss, Pythiomorpha gonapodyides H.E. Petersen; Neotypifications (basionym): Phloeophthora syringae Kleb., Phytophthora meadii McRae Citation: Abad ZG, Burgess TI, Bourret T, Bensch K, Cacciola S, Scanu B, Mathew R, Kasiborski B, Srivastava S, Kageyama K, Bienapfl JC, Verkleij G, Broders K, Schena L, Redford AJ (2023). Phytophthora: taxonomic and phylogenetic revision of the genus. Studies in Mycology 106: 259-348. doi: 10.3114/sim.2023.106.05.

6.
Nanotechnology ; 33(21)2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35130523

RESUMO

Magnetism induced by defects in nominally non-magnetic solids has attracted intense scientific interest in recent years. The local magnetism in highly disordered undoped and Co-doped topological insulator (TI) Bi2Se3nanoplates has been investigated by muon spin relaxation (µSR). UsingµSR spectroscopy, together with other macroscopic characterizations, we find that these nanoplates are composed of a core with both static fields and dynamically fluctuating moments, and a shell with purely dynamically fluctuating moments. The fluctuations in the core die out at low temperatures, while those in the shell continue till 2 K. When Bi2Se3is doped with Co, the static magnetic component increases, whilst keeping the dual (static-plus-dynamic) nature intact. The findings indicate that highly disordered TI's could constitute a new class of promising magnetic materials that can be engineered by magnetic impurity doping.

7.
Anim Biotechnol ; 33(7): 1441-1448, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33866921

RESUMO

The present study was designed to evaluate the effect of factors like hormones, antisperm antibody (ASA), and oxidative stress and its relation with semen quality in crossbred bulls. Ejaculates from two bulls were categorized into good (n = 12) and poor (n = 12) based on initial progressive motility, that is, ≥70% and ≤50%, respectively. The level of hormones like Testosterone (p < 0.05) and PGE2 (p < 0.01) was significantly higher in good-quality ejaculates compared to poor-quality ejaculates; however, estradiol (p < 0.05), progesterone, oxidative stress, and ASAs were significantly higher (p < 0.01) in poor-quality ejaculates compared to good-quality ejaculates. Therefore, it could be concluded that oxidative stress and hormonal imbalance might have resulted in high number of dead and defective spermatozoa which was ultimately responsible for poor quality semen ejaculates.


Assuntos
Análise do Sêmen , Espermatozoides , Bovinos , Animais , Masculino , Sêmen , Anticorpos , Testosterona , Estresse Oxidativo , Motilidade dos Espermatozoides
8.
Med J Armed Forces India ; 78(2): 180-184, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35463542

RESUMO

Background: Helicobacter pylori infection has been known to be associated with dyspepsia for more than two decades; however, studies on this topic in India are limited. This study was carried out to estimate the Helicobacter pylori infection rates in non-ulcer dyspepsia. Methods: Helicobacter pylori infection rates detected by rapid urease test (RUT) positivity were analyzed in 235 patients presenting to a tertiary care center with dyspepsia having no evidence of peptic ulcer disease on esophagogastroduodenoscopy. Results: In this study, the prevalence of Helicobacter pylori infection diagnosed by the RUT was found to be 40.85%. Gender-based prevalence was found to be 40.14% and 41.93% for men and women, respectively. The highest prevalence was found in the age group of 30-39 years. The most common area of involvement was the isolated antrum of the stomach as seen in 93 patients. Conclusion: This study shows a modest RUT positivity rate for Helicobacter pylori infection with the commonest site of involvement being the antrum of the stomach. Further studies will be needed to assess the prevalence of Helicobacter pylori in the community to analyze the extent of infection.

9.
Toxicol Appl Pharmacol ; 426: 115647, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34271065

RESUMO

Acrolein, an electrophilic α,ß-unsaturated aldehyde, is present in foods and beverages, and is a product of incomplete combustion, and thus, reaches high ppm levels in tobacco smoke and structural fires. Exposure to acrolein is linked with cardiopulmonary toxicity and cardiovascular disease risk. The hypothesis of this study is the direct effects of acrolein in isolated murine blood vessels (aorta and superior mesenteric artery, SMA) are transient receptor potential ankyrin-1 (TRPA1) dependent. Using isometric myography, isolated aorta and SMA were exposed to increasing levels of acrolein. Acrolein inhibited phenylephrine (PE)-induced contractions (approximately 90%) in aorta and SMA of male and female mice in a concentration-dependent (0.01-100 µM) manner. The major metabolite of acrolein, 3-hydroxypropylmercapturic acid (3HPMA), also relaxed PE-precontracted SMA. As the SMA was 20× more sensitive to acrolein than aorta (SMA EC50 0.8 ± 0.2 µM; aorta EC50 > 29.4 ± 4.4 µM), the mechanisms of acrolein-induced relaxation were studied in SMA. The potency of acrolein-induced relaxation was inhibited significantly by: 1) mechanically-impaired endothelium; 2) Nω-Nitro-L-arginine methyl ester hydrochloride (L-NAME); 3) guanylyl cyclase (GC) inhibitor (ODQ); and, 4) a TRPA1 antagonist (A967079). TRPA1 positive immunofluorescence was present in the endothelium. Compared with other known TRPA1 agonists, including allyl isothiocyanate (AITC), cinnamaldehyde, crotonaldehyde, and formaldehyde, acrolein stimulated a more potent TRPA1-dependent relaxation. Acrolein, at high concentration [100 µM], induced tension oscillations (spasms) independent of TRPA1 in precontracted SMA but not in aorta. In conclusion, acrolein is vasorelaxant at low levels (physiological) yet vasotoxic at high levels (toxicological).


Assuntos
Acetilcisteína/análogos & derivados , Acroleína/farmacologia , Aorta Torácica/efeitos dos fármacos , Artéria Mesentérica Superior/efeitos dos fármacos , Canal de Cátion TRPA1/fisiologia , Acetilcisteína/sangue , Acetilcisteína/farmacologia , Acroleína/sangue , Animais , Aorta Torácica/fisiologia , Feminino , Proteínas Ativadoras de GTPase/genética , Proteínas Ativadoras de GTPase/fisiologia , Glutationa S-Transferase pi/genética , Glutationa S-Transferase pi/fisiologia , Masculino , Artéria Mesentérica Superior/fisiologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Canal de Cátion TRPA1/genética
10.
Analyst ; 146(11): 3578-3588, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-33913938

RESUMO

In this paper, we explain the electrochemical sensing of commercially available pioglitazone hydrochloride (PIOZ) tablets on a nitrogen (N) doped r-GO (Nr-GO) modified commercial glassy carbon electrode (GCE) and a commercial screen printed graphite electrode (SPGE). Nr-GO is synthesized by the chemical reduction of graphene oxide (GO) and simultaneous insertion of an N-dopant by hydrazine monohydrate. Pristine GO itself is prepared by chemical exfoliation of bulk graphite. Upon chemical reduction, the exfoliated GO sheets restack together leaving behind the doped N-atom as evidenced by XRD and Raman spectroscopy. The N-atom exists in the pyrrolinic and pyridinic form at the edge of graphitic domains which is confirmed by XPS. The as-synthesized Nr-GO is used for the preparation of electro-active electrodes with the help of the GCE and SPGE. These electrodes have the capability to oxidize PIOZ by a diffusion dominated process as evidenced by the impedance spectroscopic technique. The differential pulse voltammetric responses of different concentrations of PIOZ are assessed over the Nr-GO modified GCE and SPGE, which exhibit better limits of detection (LODs) of 67 nM and 29 nM, respectively, compared to those from earlier reports. These assays exhibit non-interfering capability in the presence of various body interferents at pH = 7.0.

11.
Clin Radiol ; 75(10): 796.e1-796.e9, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32703543

RESUMO

AIM: To assess the prevalence of various imaging manifestations in neurosarcoidosis (NS) patients at presentation and to explore if specific imaging findings may cluster in different sub-groups. MATERIALS AND METHODS: A retrospective, dual-institution, systematic imaging review was undertaken of the magnetic resonance imaging (MRI) findings in 100 consecutive NS patients who presented over a 15-year period. Clustering analysis (k-mode) was performed to evaluate co-occurrence of imaging findings. RESULTS: Non-enhancing white matter (NEWM) lesions were the most common imaging abnormality (56%), followed by leptomeningeal (47%) and pachymeningeal (32%) involvement. Other common manifestations included cranial nerve involvement (30%), parenchymal granulomas (27%), hypothalamic-pituitary-adrenal axis involvement (26%), and hydrocephalus (14%). Additionally, a higher prevalence of perivascular enhancement (23%), cerebrovascular events (including ischaemic and haemorrhagic events; 17%), and ependymal involvement (20%) were noted than recognised previously. Additional k-mode analysis was performed to explore underlying disease sub-clusters. This was evaluated for clusters varying between two though five (k=2-5). For k=4, the analysis revealed that the imaging findings may possibly be divided into disease sub-sets of four groups, each with varying distribution of imaging manifestations and clinical manifestations. CONCLUSION: Overall, NEWM lesions and meningeal involvement are the most common imaging manifestations of NS. The prevalence of perivascular enhancement, cerebrovascular events, and ependymal involvement is likely higher than reported previously. Additionally, different imaging findings in NS may cluster together and imaging subtypes in NS possibly exist.


Assuntos
Doenças do Sistema Nervoso Central/diagnóstico por imagem , Doenças do Sistema Nervoso Central/epidemiologia , Imageamento por Ressonância Magnética , Neuroimagem/métodos , Sarcoidose/diagnóstico por imagem , Sarcoidose/epidemiologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Estados Unidos/epidemiologia
12.
Nanotechnology ; 30(43): 435204, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31320602

RESUMO

The plasmon-enhanced photoresponse properties of a Ag nanoparticle decorated Bi2Se3 nanosheet (AGBS)/p-Si heterojunction device have been studied. The Ag nanoparticles, Bi2Se3 nanosheets, and AGBS nanocomposite are synthesized chemically. Microscopic investigations, ultimately of the AGBS nanocomposite, reveal that the Bi2Se3 nanosheets of thickness ∼20 nm and lateral dimension ∼1 µm are decorated with Ag nanoparticles of sizes 20-40 nm in the nanocomposite. The x-ray diffraction pattern of AGBS shows that apart from being in a metallic state, the Ag in the AGBS is also in the form of compounds with Bi, Se, and additionally O. This observation is further complemented by the x-ray photoelectron spectrum, which shows the presence of Ag0 and Ag+ states of Ag in AGBS. The UV-visible absorption spectra show the plasmonic peak of the Ag nanoparticles occurs at 420 nm; the peak is shifted to ∼500 nm in AGBS due to the modified dielectric environment of the nanoparticles. The AGBS/p-Si heterojunction shows excellent photoresponse properties, with a responsivity of 0.28 A/W, a fairly high detectivity of 4 × 1010 Jones, and an EQE of 71% under 10 V reverse bias at a 500 nm wavelength. The plasmon enhanced photoresponse at the selective wavelength makes this material attractive for high performance optoelectronic devices.

13.
Phys Chem Chem Phys ; 21(30): 16634-16646, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31317146

RESUMO

The thermal spike model (TSM), a widely accepted mechanism of swift heavy ion (SHI)-matter interactions, provides explanation for various SHI induced effects, including mixing across interfaces. We assess the validity of the model via tuning the electron-phonon coupling strength (G) by taking a series Pd1-xNix of a completely solid soluble binary, and then observing Pd1-xNix/Si interface mixing induced by a combination of 100 MeV Au ion irradiation and 4 keV Ar ion sputtering. If the TSM truly describes the SHI-matter interaction mechanism, any non-linearity in x-variation of G must also result in a similar non-linearity in the x-dependence of mixing. Experimentally, the extent of mixing has been parametrized by the irradiation induced change Δσ2 in variances of Pd and Ni depth profiles derived from XPS. Computationally, G determined using density functional theory has been used to solve the equations appropriate to the TSM, and then an equivalent quantity L2, proportional to Δσ2, has been calculated. Both Δσ2(x) and L2(x) show non-linearities, albeit in slightly dissimilar ways, leading to a conjecture that the present work at least does not invalidate the TSM.

14.
J Appl Microbiol ; 126(4): 1117-1127, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30556924

RESUMO

AIMS: The aims of the study were to (i) isolate and characterize arsenic-tolerant bacterial strains, (ii) study the plant growth-promoting traits and (iii) explore their bioremediation potential. METHODS AND RESULTS: Indigenous arsenic hypertolerant bacterial isolates NM02 and NM03 were screened as they were capable of growing at 150 mmol l-1 As (V) and 70 mmol l-1 As (III). They were identified on the basis of morphological, physiological and biochemical parameter and 16sDNA sequence as Bacillus flexus and Acinetobacter junii respectively. Genomic DNA analysis for the investigation of ars operon revealed the presence of metalloregulatory arsC gene, suggesting their ability to detoxify arsenic. The analysis for siderophore, phosphate solubilization, indole acetic acid (IAA) and ACC deaminase highlighted the intrinsic plant growth-promoting rhizobacteria traits of both the bacterial strains. The energy dispersive spectroscopy analysis proved the potential of cellular arsenic sequestration within the strains. Moreover, Fourier-transform infrared spectra revealed the repositioning of the spectral bands in As presence, indicating the presence of those functional groups on the bacterial surface that is involved in As adsorption. CONCLUSIONS: Our results indicate that bacterial strains NM02 and NM03 were identified as potent applicants for arsenic bioremediation and possess the ability to facilitate plant growth. SIGNIFICANCE AND IMPACT OF THE STUDY: The bacterial strains are proficient in As detoxification and can be employed for arsenic bioremediation; a cost-effective and in situ remediation technique for the polluted soil.


Assuntos
Acinetobacter/fisiologia , Arsênio/metabolismo , Bacillus/fisiologia , Microbiologia do Solo , Poluentes do Solo/metabolismo , Acinetobacter/classificação , Acinetobacter/genética , Acinetobacter/metabolismo , Adaptação Fisiológica , Bacillus/classificação , Bacillus/genética , Bacillus/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biodegradação Ambiental , Reguladores de Crescimento de Plantas , RNA Ribossômico 16S/genética
15.
Mikrochim Acta ; 186(7): 415, 2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-31187276

RESUMO

A voltammetric method is described for the determination of chloroquine (CQ) and validated simultaneously by two techniques and in three different conditions. The WS2 quantum dots (WS2 QDs) were synthesized by a hydrothermal method and then placed on reduced graphene oxide (rGO) sheets. The resulting composite material was then deposited on a glassy carbon electrode (GCE) where it showed excellent electroactivity. The modified GCE responds to chloroquine at a typical potential maximum of 1.2 V (vs. AgCl/Ag). Techniques including cyclic voltammetry and differential pulse voltammetry were tested. Features of merit include (a) a wide linear response (in the 0.5 µM to 82 µM CQ concentration range), (b) an electrochemical sensitivity of 0.143-0.90 µA·µM-1·cm-2), and a 40-120 nM limit of detection (at S/N = 3). The sensor has excellent selectivity even in the presence of potentially interfering biological compounds. Responses were tested in phosphate buffer, human serum and pharmaceutical formulations, and no cross reactivity or matrix effects were found. In all the three cases, quite satisfactory recoveries were obtained. Graphical abstract Schematic representation of the mechanism for electro-oxidation of chloroquine on a glassy carbon electrode modified with an rGO@WS2 quantum dot composite. The sensor displays enhanced electrocatalytic activity towards chloroquine. The method was validated in biological samples and pharmaceutical formulations.

16.
J Environ Manage ; 244: 144-153, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31121501

RESUMO

To accelerate the process of decomposition using consortia of thermophilic ligno-cellulolytic fungi, different crop residues viz. sorghum (SG), soybean (SS), maize (MS), sugarcane (SC), cotton (CS) and pigeon pea (PS) with a varied C:N ratio and sawdust (SD) having high lignin content were collected and used for decomposition process. Compost quality assessed by evaluating different maturity and stability indices at five succeeding stages [first mesophilic (M1), thermophilic (T), second mesophilic (M2), cooling (C) and humification (H)]. A significant reduction was observed in the C:N ratio, biodegradability index, nitrification index, ratio of water-soluble carbon to organic nitrogen (WSC/Org.N) with an increase in concomitant over time while Ash (%), organic matter loss (%), CEC/TOC ratio, cellulose biodegradation ratio (BR) and lignin/cellulose ratio were significantly increased with time. By correlation study, biodegradability index (BI) and fluorescein diacetate (FDA) hydrolysis emerged as the most suitable compost maturity and stability parameters, respectively. Principal component analysis (PCA) results confirmed that BI, BR, WSC/Org. N and FDA can be regarded as key indicators for assessing compost quality. Our findings conclude that fungal consortia of Tricoderma viride, Rhizomucor pusillus, Aspergillus awamori and Aspergillus flavus can accelerate decomposition time from 8 to 12 months (which is normal farming practice) to 120 days.


Assuntos
Solo , Gerenciamento de Resíduos , Carbono , Fungos , Nitrogênio , Temperatura
17.
J Relig Health ; 58(1): 87-108, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29192361

RESUMO

The present study is conducted on 300 PG-level college students in Haridwar, Uttarakhand (India). The aim of the present study is to examine the level of spiritual intelligence and mental health, to observe relationship between these two variables and also to identify the difference in spiritual intelligence and mental health across gender and educational background (arts and science). The purposive sampling technique is used to select 300 college students of both disciplines of arts and science from the four different government degree colleges/campuses in Haridwar. Integrated Spiritual Intelligence Scale and Mithila Mental Health Status Inventory are used to observe the level of these variables among college students. In the present study, correlational design is employed. All the statistical analyses are done with the help of computer software SPSS. To observe relationship Pearson correlation and to identify the difference t test are used. Findings of the study revealed that spiritual intelligence and mental health relate significantly among arts students, and male and female arts students separately have significant relationship between spiritual intelligence and mental health. Spiritual intelligence and mental health relate significantly among science students, and male and female science students separately have significant relationship between spiritual intelligence and mental health. No significant difference is found between male and female students in terms of spiritual intelligence. No significant difference is found between arts and science students in terms of spiritual intelligence. No significant difference is found between male and female students in terms of mental health. No significant difference is found between arts and science students in terms of mental health.


Assuntos
Saúde Mental , Espiritualidade , Estudantes , Escolaridade , Feminino , Humanos , Índia , Inteligência , Masculino , Fatores Sexuais , Universidades
18.
Nanotechnology ; 29(49): 495401, 2018 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-30207539

RESUMO

With a central curved chassis, a four-wheeled molecule-vehicle was deposited on a Au(111) surface and imaged at low temperature using a scanning tunneling microscope. The curved conformation of the chassis and the consequent moderate interactions of the four wheels with the surface were observed. The dI/dV constant current maps of the tunneling electronic resonances close to the Au(111) Fermi level were recorded to identify the potential energy entry port on the molecular skeleton to trigger and control the driving of the molecule. A lateral pushing mode of molecular manipulation and the consequent recording of the manipulation signals confirm how the wheels can step-by-step rotate while passing over the Au(111) surface native herringbone reconstructions. Switching a phenyl holding a wheel to the chassis was not observed for triggering a lateral molecular motion inelastically and without any mechanic push by the tip apex. This points out the necessity to encode the sequence of the required wheels action on the profile of the potential energy surface of the excited states to be able to drive a molecule-vehicle.

19.
Clin Radiol ; 73(5): 428-438, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29329730

RESUMO

Endovascular mechanical thrombectomy (MT) is reserved for acute ischaemic stroke secondary to large vessel occlusion. The various MT techniques employed in the treatment of hyperacute strokes are constantly evolving with new devices and improvisation of existing technology (Wahlgren, et al 2016). In this review, we describe a variety of MT techniques gained from our experience of performing over 350 procedures in 7 years of providing a 24/7 service within the national framework of a hyperacute stroke centre. We outline a number of endovascular techniques, procedure limitations, and potential complications.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/cirurgia , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/cirurgia , Trombectomia/métodos , Procedimentos Endovasculares , Humanos
20.
Clin Radiol ; 73(7): 610-624, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29549997

RESUMO

Budd-Chiari syndrome (BCS) is a clinical condition resulting from impaired hepatic venous drainage, in which there is obstruction to the hepatic venous outflow at any level from the small hepatic veins to the junction of the inferior vena cava and the right atrium leading to hepatic congestion. The diagnosis of BCS is based on imaging, which can be gathered from non-invasive investigations such as ultrasonography coupled with venous Doppler, triphasic computed tomography (CT) and magnetic resonance imaging (MRI). Apart from diagnosis, various interventional radiology procedures aid in the successful management of this syndrome. In this article, we present various imaging features of BCS along with various interventional procedures that are used to treat this diverse condition.


Assuntos
Síndrome de Budd-Chiari/diagnóstico por imagem , Diagnóstico por Imagem/métodos , Veias Hepáticas/diagnóstico por imagem , Veia Cava Inferior/diagnóstico por imagem , Síndrome de Budd-Chiari/patologia , Síndrome de Budd-Chiari/terapia , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/patologia , Veias Hepáticas/patologia , Humanos , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Ultrassonografia , Veia Cava Inferior/patologia
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