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1.
Nature ; 582(7810): E1, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32494072

RESUMEN

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

2.
Nature ; 575(7782): 315-319, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31590178

RESUMEN

An axion insulator is a correlated topological phase, which is predicted to arise from the formation of a charge-density wave in a Weyl semimetal1,2-that is, a material in which electrons behave as massless chiral fermions. The accompanying sliding mode in the charge-density-wave phase-the phason-is an axion3,4 and is expected to cause anomalous magnetoelectric transport effects. However, this axionic charge-density wave has not yet been experimentally detected. Here we report the observation of a large positive contribution to the magnetoconductance in the sliding mode of the charge-density-wave Weyl semimetal (TaSe4)2I for collinear electric and magnetic fields. The positive contribution to the magnetoconductance originates from the anomalous axionic contribution of the chiral anomaly to the phason current, and is locked to the parallel alignment of the electric and magnetic fields. By rotating the magnetic field, we show that the angular dependence of the magnetoconductance is consistent with the anomalous transport of an axionic charge-density wave. Our results show that it is possible to find experimental evidence for axions in strongly correlated topological condensed matter systems, which have so far been elusive in any other context.

3.
Phys Rev Lett ; 132(9): 097001, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38489656

RESUMEN

Building large-scale superconducting quantum circuits will require miniaturization and integration of supporting devices including microwave circulators, which are currently bulky, stand-alone components. Here, we report the measurement of microwave scattering from a ring of Josephson junctions, with dc-only control fields. We detect the effect of quasiparticle tunneling, and dynamically classify the system at its operating design point into different quasiparticle sectors. We optimize the device within one of the quasiparticle sectors, where we observe an unambiguous signature of nonreciprocal 3-port scattering within that sector. This enables operation as a circulator, and at the optimal circulation point, we observe on-resonance insertion loss of 2 dB, isolation of 14 dB, power reflectance of -11 dB, and a bandwidth of 200 MHz, averaged over the 3 input ports.

4.
Hum Genomics ; 17(1): 49, 2023 06 12.
Artículo en Inglés | MEDLINE | ID: mdl-37303042

RESUMEN

BACKGROUND: Individuals infected with SARS-CoV-2 vary greatly in their disease severity, ranging from asymptomatic infection to severe disease. The regulation of gene expression is an important mechanism in the host immune response and can modulate the outcome of the disease. miRNAs play important roles in post-transcriptional regulation with consequences on downstream molecular and cellular host immune response processes. The nature and magnitude of miRNA perturbations associated with blood phenotypes and intensive care unit (ICU) admission in COVID-19 are poorly understood. RESULTS: We combined multi-omics profiling-genotyping, miRNA and RNA expression, measured at the time of hospital admission soon after the onset of COVID-19 symptoms-with phenotypes from electronic health records to understand how miRNA expression contributes to variation in disease severity in a diverse cohort of 259 unvaccinated patients in Abu Dhabi, United Arab Emirates. We analyzed 62 clinical variables and expression levels of 632 miRNAs measured at admission and identified 97 miRNAs associated with 8 blood phenotypes significantly associated with later ICU admission. Integrative miRNA-mRNA cross-correlation analysis identified multiple miRNA-mRNA-blood endophenotype associations and revealed the effect of miR-143-3p on neutrophil count mediated by the expression of its target gene BCL2. We report 168 significant cis-miRNA expression quantitative trait loci, 57 of which implicate miRNAs associated with either ICU admission or a blood endophenotype. CONCLUSIONS: This systems genetics study has given rise to a genomic picture of the architecture of whole blood miRNAs in unvaccinated COVID-19 patients and pinpoints post-transcriptional regulation as a potential mechanism that impacts blood traits underlying COVID-19 severity. The results also highlight the impact of host genetic regulatory control of miRNA expression in early stages of COVID-19 disease.


Asunto(s)
COVID-19 , MicroARNs , Humanos , COVID-19/genética , SARS-CoV-2/genética , Genómica , MicroARNs/genética , ARN Mensajero
5.
Mol Pharm ; 2024 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-39360744

RESUMEN

Using the time-temperature-transformation diagrams, we demonstrated a correlation between molecular mobility and crystallization in amorphous solid dispersions of nifedipine (NIF) with each polyvinylpyrrolidone vinyl acetate (PVPVA64) and polyvinyl caprolactam polyvinyl acetate-polyethylene glycol graft copolymer (Soluplus). The behavior was compared with the NIF dispersions prepared with each polyvinylpyrrolidone (PVP) and hydroxypropyl methylcellulose acetate succinate (HPMCAS) [Lalge et al., Mol. Pharmaceutics 2023, 20(3), 1806-1817]. Each system was characterized by a unique temperature at which the crystallization onset time was the shortest. Below this temperature, a coupling was observed between the α-relaxation time determined by dielectric spectroscopy and crystallization onset time. Above this temperature, the activation barrier for crystallization had a more significant role than molecular mobility. In the solid state, PVP and PVPVA64 dispersion exhibited higher resistance to crystallization than HPMCAS and Soluplus. The role of polymers in inhibiting crystal growth in nucleated systems was discerned by monitoring crystallization following wetting of the amorphous dispersion with the dissolution medium. PVPVA64 and Soluplus dispersions exhibited higher resistance to crystal growth than PVP and HPMCAS.

6.
Rev Med Virol ; 33(5): e2471, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37529971

RESUMEN

Studies related to clinical diagnosis and research of SARS-CoV-2 are important in the current pandemic era. Although molecular biology has emphasised the importance of qualitative analysis, quantitative analysis with nucleic acids in relation to SARS-CoV-2 needs to be clearly emphasised, which can provide perspective for viral dynamic studies of SARS-CoV-2. In this regard, the requirement and utilization of digital PCR in COVID-19 research has substantially increased during the pandemic, necessitating the aggregation of its cardinal applications and future scopes. Hence, this meta-review comprehensively addresses and emphasises the importance of nucleic acid quantification of SARS-CoV-2 RNA with digital PCR (dPCR). Various quantitative techniques of clinical significance like immunological, proteomic and nucleic acid-based diagnosis and quantification, have been comparatively discussed. Furthermore, the core part of the article focusses on the working principle and advantages of digital PCR, along with its applications in COVID-19 research. Several important applications like viral load quantitation, environmental surveillance and assay validation have been extensively investigated and discussed. Certain key future scopes of clinical importance, like mortality prediction, viral/variant-symbiosis, and antiviral studies were also identified, suggesting several possible digital PCR applications in COVID-19 research.


Asunto(s)
COVID-19 , Ácidos Nucleicos , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , ARN Viral/genética , Proteómica , Reacción en Cadena de la Polimerasa/métodos , Prueba de COVID-19
7.
Phys Chem Chem Phys ; 26(17): 13497-13505, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38651229

RESUMEN

BSTS epitaxial thin film topological insulators were grown using the MBE technique on two different types of substrates i.e., Si (111) and SiC/graphene with Bi0.7Sb1.6Te1.8Se0.9 and Bi0.9Sb1.5Te1.8Se1.1, respectively. The crystallographic properties of BSTS films were investigated via X-ray diffraction, which showed the strongest reflections from the (0 0 l) facets corresponding to the rhombohedral phase. Superior epitaxial growth, homogeneous thickness, smooth surfaces, and larger unit cell parameters were observed for the films grown on the Si substrate. Polarization dependent Raman spectroscopy showed a weak appearance of the Ag mode in cross--polarized geometry. In contrast, a strong Eg mode was observed in both parallel and cross-polarized geometries which correspond to the rhombohedral crystal symmetry of BSTS films. A redshift of Ag and Eg modes was observed in the Raman spectra of BSTS films grown on the Si substrate, compared to those on SiC/graphene, which was directly associated with the unit cell parameter and composition of the films. Raman spectra showed four fundamental modes with asymmetric line shape, and deconvolution of the peaks resulted in additional modes in both the BSTS thin films. The sum of relative ratios of linewidths of fundamental modes (Ag and Eg) of BSTS films grown on Si substrate was lower, indicating a more ordered structure with lower contribution of defects as compared to BSTS film grown on SiC/graphene substrate.

8.
J Environ Manage ; 354: 120477, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38417362

RESUMEN

The Indian coastal waters are stressed due to a multitude of factors, such as the discharge of industrial effluents, urbanization (municipal sewage), agricultural runoff, and river discharge. The coastal waters along the eastern and western seaboard of India exhibit contrasting characteristics in terms of seasonality, the magnitude of river influx, circulation pattern, and degree of anthropogenic activity. Therefore, understanding these processes and forecasting their occurrence is highly necessary to secure the health of coastal waters, habitats, marine resources, and the safety of tourists. This article introduces an integrated buoy-satellite based Water Quality Nowcasting System (WQNS) to address the unique challenges of water quality monitoring in Indian coastal waters and to boost the regional blue economy. The Indian National Centre for Ocean Information Services (INCOIS) has launched a first-of-its-kind WQNS, and positioned the buoys at two important locations along the east (Visakhapatnam) and west (Kochi) coast of India, covering a range of environmental conditions and tourist-intensive zones. These buoys are equipped with different physical-biogeochemical sensors, data telemetry systems, and integration with satellite-based observations for real-time data transmission to land. The sensors onboard these buoys continuously measure 22 water quality parameters, including surface current (speed and direction), salinity, temperature, pH, dissolved oxygen, phycocyanin, phycoerythrin, Coloured Dissolved Organic Matter, chlorophyll-a, turbidity, dissolved methane, hydrocarbon (crude and refined), scattering, pCO2 (water and air), and inorganic macronutrients (nitrite, nitrate, ammonium, phosphate, silicate). This real-time data is transmitted to a central processing facility at INCOIS, and after necessary quality control, the data is disseminated through the INCOIS website. Preliminary results from the WQNS show promising outcomes, including the short-term changes in the water column oxic and hypoxic regimes within a day in coastal waters off Kochi during the monsoon period, whereas effluxing of high levels of CO2 into the atmosphere associated with the mixing of water, driven by local depression in the coastal waters off Visakhapatnam. The system has demonstrated its ability to detect changes in the water column properties due to episodic events and mesoscale processes. Additionally, it offers valuable data for research, management, and policy development related to coastal water quality.


Asunto(s)
Ecosistema , Calidad del Agua , India , Océanos y Mares , Naciones Unidas , Monitoreo del Ambiente , Agua de Mar/química
9.
J Prosthet Dent ; 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39353753

RESUMEN

Dental practitioners often rehabilitate patients with excessive gingival display during the broad wide smile. The transition line is defined as the lip line, which depicts transition between the prosthesis and adjacent soft tissue. Correctly predicting and managing this transition line is especially important, as it determines esthetics when the patient smiles widely. Photowrapping is a digital technique used to trace the transition line on digital imaging and communications in medicine (DICOM) files by wrapping a 2-dimensional photograph onto the image, providing the soft tissue information required for esthetics and helping clinicians to determine accurately the need for bone reduction during implant planning. The imaging software program (Dolphin 3D; Patterson Dental Holdings, Inc) and photographs are used in this technique. This article presents a digital technique for tracing the dynamic smile line by photowrapping around the DICOM image.

10.
Environ Geochem Health ; 46(4): 122, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38483653

RESUMEN

This study aims to explore the concentrations of Se and Hg in shellfish along the Gulf of Mannar (GoM) coast (Southeast India) and to estimate related risks and risk-based consumption limits for children, pregnant women, and adults. Se concentrations in shrimp, crab, and cephalopods ranged from 0.256 to 0.275 mg kg-1, 0.182 to 0.553 mg kg-1, and 0.176 to 0.255 mg kg-1, respectively, whereas Hg concentrations differed from 0.009 to 0.014 mg kg-1, 0.022 to 0.042 mg kg-1 and 0.011 to 0.024 mg kg-1, respectively. Se and Hg content in bamboo shark (C. griseum) was 0.242 mg kg-1 and 0.082 mg kg-1, respectively. The lowest and highest Se concentrations were found in C. indicus (0.176 mg kg-1) and C. natator (0.553 mg kg-1), while Hg was found high in C. griseum (0.082 mg kg-1) and low in P. vannamei (0.009 mg kg-1). Se shellfishes were found in the following order: crabs > shrimp > shark > cephalopods, while that of Hg were shark > crabs > cephalopods > shrimp. Se in shellfish was negatively correlated with trophic level (TL) and size (length and weight), whereas Hg was positively correlated with TL and size. Hg concentrations in shellfish were below the maximum residual limits (MRL) of 0.5 mg kg-1 for crustaceans and cephalopods set by FSSAI, 0.5 mg kg-1 for crustaceans and 1.0 mg kg-1 for cephalopods and sharks prescribed by the European Commission (EC/1881/2006). Se risk-benefit analysis, the AI (actual intake):RDI (recommended daily intake) ratio was > 100%, and the AI:UL (upper limit) ratio was < 100%, indicating that all shellfish have sufficient level of Se to meet daily requirements without exceeding the upper limit (UL). The target hazard quotient (THQ < 1) and hazard index (HI < 1) imply that the consumption of shellfish has no non-carcinogenic health impacts for all age groups. However, despite variations among the examined shellfish, it was consistently observed that they all exhibited a Se:Hg molar ratio > 1. This finding implies that the consumption of shellfish is generally safe in terms of Hg content. The health benefit indexes, Se-HBV and HBVse, consistently showed high positive values across all shellfish, further supporting the protective influence of Se against Hg toxicity and reinforcing the overall safety of shellfish consumption. Enhancing comprehension of food safety analysis, it is crucial to recognize that the elevated Se:Hg ratio in shellfish may be attributed to regular selenoprotein synthesis and the mitigation of Hg toxicity by substituting Se bound to Hg.


Asunto(s)
Mercurio , Selenio , Contaminantes Químicos del Agua , Embarazo , Animales , Niño , Adulto , Femenino , Humanos , Mercurio/análisis , Selenio/análisis , Monitoreo Biológico , Peces/metabolismo , Mariscos/análisis , Crustáceos , Medición de Riesgo , Contaminantes Químicos del Agua/análisis
11.
J Food Sci Technol ; 61(5): 1003-1012, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38487293

RESUMEN

Traditional meat products like Haleem play a pivotal role in the culinary landscapes of Indian consumers, along with high economic value and business potential. Due to anticipated gains associated with adulterating 'Haleem' and constant evasion from regulatory oversight, the susceptibility to adulteration has substantially increased. Furthermore, no reports/surveillance regarding their labelling compliance has been reported. Hence, we conducted a 2-year surveillance using 100 samples collected from Hyderabad, India, using the Chipron™ DNA macroarray analysis technique. The method was validated for sensitivity (1%), specificity, and with proficiency test samples. Following this, the surveillance samples (beef, chicken, and mutton Haleem) were tested. The surveillance revealed an alarming adulteration of 46% of the samples, with different proportions of adulterant species. Adulteration of unconventional meat like camel meat was also found. These concerning results necessitate the requirement of stricter and constant regulatory surveillance to safeguard consumer trust and preserve the authenticity of traditional meat products. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-024-05947-9.

12.
Niger J Clin Pract ; 27(4): 534-536, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38679778

RESUMEN

ABSTRACT: A femoral hernia is an uncommon and acquired hernia in the groin. Its incidence in adults is 2%-8% of all abdominal wall hernias, and it has a female-to-male ratio of 1.8:1. It is usually found in elderly patients and is associated with increased morbidity due to delays in diagnosis leading to a high incidence of incarceration and strangulation. Accurate preoperative diagnosis of femoral hernia is challenging, especially in obese patients in whom a small femoral hernia can be hidden under the groin fat. Unlike an inguinal hernia, it rarely reduces on its own and if asymptomatic and small, is often unnoticed by the elderly obese patient. Femoral hernia is often unsuspected and overlooked in males as it is predominant among females. Delay in diagnosis can lead to intestinal gangrene and high morbidity. We present a case of an incarcerated left femoral hernia in an elderly obese male who presented with acute intestinal obstruction. He was managed with resection of the gangrenous segment and double barrel ileostomy. Although uncommon in males, a femoral hernia has a high incidence of strangulation, and therefore should always be ruled out as a cause of acute intestinal obstruction in elderly patients. Therefore, never forget to examine the groin in case of intestinal obstruction.


Asunto(s)
Hernia Femoral , Obstrucción Intestinal , Humanos , Hernia Femoral/cirugía , Hernia Femoral/diagnóstico , Hernia Femoral/complicaciones , Masculino , Obstrucción Intestinal/etiología , Obstrucción Intestinal/diagnóstico , Obstrucción Intestinal/cirugía , Anciano , Tomografía Computarizada por Rayos X , Obesidad/complicaciones , Gangrena/diagnóstico , Gangrena/cirugía , Diagnóstico Diferencial
13.
Mol Pharm ; 20(3): 1806-1817, 2023 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-36744878

RESUMEN

The critical cooling rate (CRcrit) to prevent drug crystallization during the preparation of nifedipine amorphous solid dispersions (ASDs) was determined through the time-temperature-transformation (TTT) diagram. ASDs were prepared with polyvinylpyrrolidone, hydroxypropylmethyl cellulose acetate succinate, and poly(acrylic acid). ASDs were subjected to isothermal crystallization over a wide temperature range, and the time and temperature dependence of nifedipine crystallization onset time (tC) was determined by differential scanning calorimetry (DSC) and synchrotron X-ray diffractometry. TTT diagrams were generated for ASDs, which provided the CRcrit for the dispersions prepared with each polymer. The observed differences in CRcrit could be explained in terms of differences in the strength of interactions. Stronger drug-polymer interactions led to longer tC and decreased CRcrit. The effect of polymer concentrations (4-20% w/w) was also influenced by the strength of the interaction. The CRcrit of amorphous NIF was ∼17.5 °C/min. Addition of 20% w/w polymer resulted in a CRcrit of ∼0.05, 0.2, and 11 °C/min for the dispersions prepared with PVP, HPMCAS, and PAA, respectively.


Asunto(s)
Nifedipino , Polímeros , Polímeros/química , Cristalización , Temperatura , Nifedipino/química , Povidona/química , Solubilidad , Rastreo Diferencial de Calorimetría
14.
Mol Pharm ; 20(8): 4196-4209, 2023 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-37358932

RESUMEN

In an earlier investigation, the critical cooling rate to prevent drug crystallization (CRcrit) during the preparation of nifedipine (NIF) amorphous solid dispersions (ASDs) was determined through a time-temperature transformation (TTT) diagram (Lalge et al. Mol. Pharmaceutics 2023, 20 (3), 1806-1817). The current study aims to use the TTT diagram to determine the critical cooling rate to prevent drug nucleation (CRcrit N) during the preparation of ASDs. ASDs were prepared with each polyvinylpyrrolidone (PVP) and hydroxypropyl methylcellulose acetate succinate (HPMCAS). The dispersions were first stored under conditions promoting nucleation and then heated to the temperature that favors crystallization. The crystallization onset time (tC) was determined by differential scanning calorimetry and synchrotron X-ray diffractometry. TTT diagrams for nucleation were generated, which provided the critical nucleation temperature (50 °C) and the critical cooling rate to avoid nucleation (CRcrit N). The strength of the drug-polymer interactions as well as the polymer concentration affected the CRcrit N, with PVP having a stronger interaction than HPMCAS. The CRcrit of amorphous NIF was ∼17.5 °C/min. The addition of a 20% w/w polymer resulted in CRcrit of ∼0.05 and 0.2 °C/min and CRcrit N of ∼4.1 and 8.1 °C/min for the dispersions prepared with PVP and HPMCAS, respectively.


Asunto(s)
Polímeros , Povidona , Temperatura , Povidona/química , Polímeros/química , Cristalización , Transición de Fase , Solubilidad , Metilcelulosa/química , Estabilidad de Medicamentos
15.
Ultrasound Obstet Gynecol ; 61(6): 719-727, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36610024

RESUMEN

OBJECTIVE: In-utero repair of open neural tube defects (ONTD) is an accepted treatment option with demonstrated superior outcome for eligible patients. While current guidelines recommend genetic testing by chromosomal microarray analysis (CMA) when a major congenital anomaly is detected prenatally, the requirement for an in-utero repair, based on the Management of Myelomeningocele Study (MOMS) criteria, is a normal karyotype. In this study, we aimed to evaluate if CMA should be recommended as a prerequisite for in-utero ONTD repair. METHODS: This was a retrospective cohort study of pregnancies complicated by ONTD that underwent laparotomy-assisted fetoscopic repair or open-hysterotomy fetal surgery at a single tertiary center between September 2011 and July 2021. All patients met the MOMS eligibility criteria and had a normal karyotype. In a subset of the pregnancies (n = 77), CMA testing was also conducted. We reviewed the CMA results and divided the cohort into two groups according to whether clinically reportable copy-number variants (CNV) were detected (reportable-CNV group) or not (normal-CMA group). Surgical characteristics, complications, and maternal and early neonatal outcomes were compared between the two groups. The primary outcomes were fetal or neonatal death, hydrocephalus, motor function at 12 months of age and walking status at 30 months of age. Standard parametric and non-parametric statistical tests were employed as appropriate. RESULTS: During the study period, 146 fetuses with ONTD were eligible for and underwent in-utero repair. CMA results were available for 77 (52.7%) patients. Of those, 65 (84%) had a normal CMA and 12 (16%) had a reportable CNV, two of which were classified as pathogenic. The first case with a pathogenic CNV was diagnosed with a 749-kb central 22q11.21 deletion spanning low-copy-repeat regions B-D of chromosome 22; the second case was diagnosed with a 1.3-Mb interstitial deletion at 1q21.1q21.2. Maternal demographics, clinical characteristics, operative data and postoperative complications were similar between those with normal CMA results and those with reportable CNVs. There were no significant differences in gestational age at delivery or any obstetric and early neonatal outcome between the study groups. Motor function at birth and at 12 months of age, and walking status at 30 months of age, were similar between the two groups. CONCLUSIONS: Standard diagnostic testing with CMA should be offered when an ONTD is detected prenatally, as this approach has implications for counseling regarding prognosis and recurrence risk. Our results indicate that the presence of a clinically reportable CNV should not a priori affect eligibility for in-utero repair, as overall pregnancy outcome is similar in these cases to that of cases with normal CMA. Nevertheless, significant CMA results will require a case-by-case multidisciplinary discussion to evaluate eligibility. To generalize the conclusion of this single-center series, a larger, multicenter long-term study should be considered. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Meningomielocele , Atención Prenatal , Recién Nacido , Femenino , Embarazo , Humanos , Preescolar , Estudios Retrospectivos , Atención Prenatal/métodos , Feto , Meningomielocele/cirugía , Análisis por Micromatrices/métodos , Diagnóstico Prenatal/métodos , Estudios Multicéntricos como Asunto
16.
J Phys Chem A ; 127(34): 7070-7079, 2023 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-37589487

RESUMEN

Surface-enhanced Raman spectra (SERS) and electronic-structure-based properties are important tools for investigation of the molecular sensing ability of nanoparticles. The present computational study is intended to explore the sensing ability of Zn3O3 and Mg-containing Zn3O3 structures for CO2 molecules by CHEM effects of the SERS technique. Geometries of CO2-adsorbed Zn3O3, Zn2MgO3 (Mg as a substitutional impurity), and Zn3O3Mg (Mg as an interstitial impurity) structures are modeled using the B3LYP/6-31G(d,p) level of density functional theory. The Mg site of the Zn2MgO3 and Zn3O3Mg structures is preferential for the adsorption of CO2. The observed energy trends are supported by geometrical analysis, molecular orbital interactions, redshifts in CO2 vibrational modes, and topological properties. Raman activity enhancement of the CO2 symmetric vibrational mode is significant when the molecule is adsorbed at the Mg site of Zn3O3Mg. The observed Raman activity enhancement is supported by SERS spectra obtained from anharmonic calculations carried out on B3LYP/6-31G(d,p) geometries and substantiated by a larger change in the polarizability with energy corresponding to the symmetric vibrational mode of CO2. The TDDFT calculations, frequency-dependent polarizabilities, and charge transfer interactions show that Zn3O3Mg is a good substrate for sensing of CO2, with visible wavelengths, by resonance Raman effect. The trends with adsorption energy, Raman activity, and excited state properties are also substantiated by B3LYP/6-311+G(d,p) calculations.

17.
Environ Res ; 216(Pt 4): 114766, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36370813

RESUMEN

The present study aimed at the synthesis of cobalt oxide nanoparticles (CONPs) mediated by leaf extract of Muntingia calabura using a rapid and simple method and evaluation of its photocatalytic activity against methylene blue (MB) dye. UV-vis absorption spectrum showed multiple peaks with an optical band gap of 2.05 eV, which was concordant with the literature. FESEM image signified the irregular-shaped, clusters of CONPs, and EDX confirmed the existence of the Co and O elements. The sharp peaks of XRD spectrum corroborated the crystalline nature with a mean crystallite size of 27.59 nm. Raman spectrum substantiated the purity and structural defects. XPS signified the presence of Co in different oxidation states. FTIR image revealed the presence of various phytochemicals present on the surface and the bands at 515 and 630 cm-1 designated the characteristic Co-O bonds. VSM studies confirmed the antiferromagnetic property with negligible hysteresis. The high BET specific surface area (10.31 m2/g) and the mesoporous nature of the pores of CONPs signified the presence of a large number of active sites, thus, indicating their suitability as photocatalysts. The CONPs degraded 88% of 10 mg/L MB dye within 300 min of exposure to sunlight. The degradation of MB dye occurred due to the formation of hydroxyl free radicals on exposure to sunlight, which followed first-order kinetics with rate constant of 0.0065 min-1. Hence, the CONPs synthesized herein could be applied to degrade other xenobiotics and the treatment of industrial wastewater and environmentally polluted samples.


Asunto(s)
Cobalto , Nanopartículas , Óxidos , Nanopartículas/química , Azul de Metileno/química
18.
Parasitol Res ; 123(1): 6, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38052752

RESUMEN

Leishmaniasis transmission cycles are maintained and sustained in nature by the complex crosstalk of the Leishmania parasite, sandfly vector, and the mammalian hosts (human, as well as zoonotic reservoirs). Regardless of the vast research on human host-parasite interaction, there persists a substantial knowledge gap on the parasite's development and modulation in the vector component. This review focuses on some of the intriguing aspects of the Leishmania-sandfly interface, beginning with the uptake of the intracellular amastigotes from an infected host to the development of the parasite within the sandfly's alimentary canal, followed by the transmission of infective metacyclic stages to another potential host. Upon ingestion of the parasite, the sandfly hosts an intricate repertoire of immune barriers, either to evade the parasite or to ensure its homeostatic coexistence with the vector gut microbiome. Sandfly salivary polypeptides and Leishmania exosomes are co-egested with the parasite inoculum during the infected vector bite. This has been attributed to the modulation of the parasite infection and subsequent clinical manifestation in the host. While human host-based studies strive to develop effective therapeutics, a greater understanding of the vector-parasite-microbiome and human host interactions could help us to identify the targets and to develop strategies for effectively preventing the transmission of leishmaniasis.


Asunto(s)
Leishmania , Leishmaniasis , Parásitos , Phlebotomus , Psychodidae , Animales , Humanos , Psychodidae/parasitología , Phlebotomus/parasitología , Leishmaniasis/parasitología , Interacciones Huésped-Parásitos , Mamíferos
19.
Helminthologia ; 60(2): 175-188, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37745222

RESUMEN

The successful design of strategic control measures against the blood-sucking gastrointestinal nematode, Haemonchus contortus in small ruminants can be facilitated by revealing its general features from morphology to the molecular level. In the south Gujarat region of India, a total of 2408 H. contortus were collected from 84 slaughtered sheep's abomasum, consisting of 347 males and 2061 females (1:6 ratio) (p<0.05). Furthermore, 726 H. contortus were collected from 61 goats, comprising 145 males and 581 females (1:4 ratio) (p<0.05). The male worms were approximately 12±0.06 mm long, while female worms were about 20±0.09 mm long. The vulvar morphotypes of the female worms were found to be 17.7% linguiform, 76.6 % knobbed/button (p<0.05), and 5.7 % smooth type, demonstrating common features of H. contortus. The nucleotide sequences of the Internal Transcribed Spacer 1 (ITS-1) of 165 bp or ITS-2 plus of 256 bp were aligned, and it was found that the genotypes of male and female specimens of either sheep or goat origin were identical, with a 100 % match. The present isolates shared >95 % and >94 % homology with published sequences of ITS-1 and ITS-2 plus of H. contortus, respectively, with more nucleotide transitions than transversions in the aligned sequences. The reconstructed phylogram of either ITS-1 or ITS-2 plus revealed two major clades, one for H. contortus and another for other nematodes, with Haemonchus placei showing its proximity with the clade of H. contortus. The study established the role of morphological and molecular features in identifying and differentiating H. contortus parasite at the local level.

20.
J Food Sci Technol ; 60(5): 1541-1550, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37033312

RESUMEN

Listeria contamination in foods of animal origin is one of the most concerning food safety issues. A duplex, SYBR green-based, real-time PCR assay was developed with high-resolution melting analysis-based differentiation of the genus Listeria and Listeria monocytogenes. The primers were designed and tested against other related foodborne pathogens. The assay was optimized for standard parameters in a non-orthogonal fashion and validated following international standards. The LODabs and LOQ of the assay were calculated to be 0.78 and 1.56 ng of the target DNA. The LODrel of the assay was found to be 1% Listeria DNA in background DNA. The assay was evaluated for applicability in artificially spiked samples, providing a 120 CFU/ml detection. The assay was validated with proficiency test samples and also with samples collected for surveillance analysis. This well-established and validated assay can be utilized as a qualitative and quantitative tool for addressing the Listeria contamination in the food safety contexts. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-023-05695-2.

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