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1.
Phys Chem Chem Phys ; 23(31): 16623-16628, 2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34319307

RESUMO

We have studied the magnetotransport properties and strain release mechanisms in ferroelastic La0.9Sr0.1MnO3 (LSMO) epitaxial thin films on SrTiO3 (STO)(001) substrates with different miscut angles. The substrate miscut angle plays a critical role in releasing shear strain and has a huge impact on the properties of the films. The strain relaxes by monoclinic distortion for films on low miscut substrates and for higher miscut substrates, the strain relaxation causes the formation of periodic twin domains with larger periodicities. We observe that the Curie temperature (TC) decreases systematically, and magnetoresistance (MR) increases with increasing the miscut angle. Such changes in the magnetic and transport properties could be due to the increased density of phase boundaries (PBs) with the increase of miscut angle. This work provides a way to tailor film microstructures and subsequent functional properties of other complex oxide films on miscut substrates with symmetry mismatch.

2.
Radiol Case Rep ; 19(12): 6230-6234, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39387007

RESUMO

Hydatid cyst is the condition caused by larvae of the parasite Echinococcus granulosus, usually involving the liver, lung, and spleen. Involvement of the cerebrum with a hydatid cyst is a rare entity, comprising 2%-3% of all cases of hydatidosis. Intraventricular extension of cerebral hydatid cysts occurs in only a limited percentage of cases. Cerebral hydatid cysts can present with nonspecific symptoms, usually with features of raised intracranial pressure. Therefore, it is crucial to consider cerebral hydatid cysts as a potential diagnosis, especially in pediatric patients with nonspecific neurological symptoms, particularly those from areas endemic to the parasite. We report a case of a 9-year-old girl who presented with progressive headache and vomiting, with imaging findings suggestive of a giant hydatid cyst in the brain. She was managed surgically with a good outcome.

3.
Adv Mater ; 36(40): e2402484, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39219216

RESUMO

Topotactic reduction is critical to a wealth of phase transitions of current interest, including synthesis of the superconducting nickelate Nd0.8Sr0.2NiO2, reduced from the initial Nd0.8Sr0.2NiO3/SrTiO3 heterostructure. Due to the highly sensitive and often damaging nature of the topotactic reduction, however, only a handful of research groups have been able to reproduce the superconductivity results. A series of in situ synchrotron-based investigations reveal that this is due to the necessary formation of an initial, ultrathin layer at the Nd0.8Sr0.2NiO3 surface that helps to mediate the introduction of hydrogen into the film such that apical oxygens are first removed from the Nd0.8Sr0.2NiO3 / SrTiO3 (001) interface and delivered into the reducing environment. This allows the square-planar / perovskite interface to stabilize and propagate from the bottom to the top of the film without the formation of interphase defects. Importantly, neither geometric rotations in the square planar structure nor significant incorporation of hydrogen within the films is detected, obviating its need for superconductivity. These findings unveil the structural basis underlying the transformation pathway and provide important guidance on achieving the superconducting phase in reduced nickelate systems.

4.
Clin Case Rep ; 11(7): e7601, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37415580

RESUMO

Key Clinical Message: The etiology of neural tube defects is multifactorial, with a wide interplay of genetic and environmental factors. However, periconceptional folic acid should be supplemented in antenatal care. Abstract: We described a case of neural tube defects (NTDs), specifically occipital encephalomeningocele, in a child born to a mother who received folic acid supplementation. A wide interplay of genetic and environmental factors exists in its causation. Although folic acid confers advantage, the relationship with the causation of NTDs still remains unclear.

5.
J Nepal Health Res Counc ; 20(3): 653-658, 2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36974852

RESUMO

BACKGROUND: We did this study to evaluate the prevalence of low birth weight among deliveries, adolescent pregnancy and advanced maternal age pregnancy. We also assessed the factors affecting the low birth weight among institutional deliveries at the level of primary hospital. METHODS: A hospital-based retrospective cross-sectional study was done in Grahun Primary Hospital of Syangja, Nepal using data maintained in register book over last five years. We excluded all those deliveries with multiple pregnancy and incomplete records, and included 2473 participants in final analysis using convenient sampling. The relevant information was filled up in Microsoft Excel 2019 v16.0 and descriptive and inferential statistics was calculated using statistical package for social sciences, IBM SPSS® v21 (IBM, Armonk, New York). RESULTS: The prevalence of low birth weight at Grahun Primary Hospital was 11.08%. The prevalence of adolescent pregnancy and advanced maternal age pregnancy was 18.03% and 02.18% respectively. Male newborns had significantly higher mean birth weight as compared to the female newborns (3101.48 ± 506.60 v/s 2967.53 ± 484.97, P-value <0.001). Female newborns had higher odds of low birth weight as compared to those male newborns (11.99% v/s 8.29%, AOR=1.56, 95% CI= 1.17-2.07). Pregnant women with lower gestational age (<37 weeks or preterm) had a higher odds of low birth weight as compared to pregnant women with normal gestational age (37-42 weeks) (AOR = 11.59, 95% CI 8.49-15.83). CONCLUSIONS: The low birth weight depends upon gestational age of mother and gender of newborn. Local organizations should work to bring down low birth weight, and adolescent pregnancy and advanced maternal age pregnancy of mother.


Assuntos
Recém-Nascido de Baixo Peso , Gravidez , Recém-Nascido , Feminino , Masculino , Adolescente , Humanos , Lactente , Idade Materna , Estudos Retrospectivos , Estudos Transversais , Nepal/epidemiologia , Peso ao Nascer , Fatores de Risco
6.
Adv Sci (Weinh) ; 10(15): e2207481, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37012611

RESUMO

Transition metal oxides exhibit a plethora of electrical and magnetic properties described by their order parameters. In particular, ferroic orderings offer access to a rich spectrum of fundamental physics phenomena, in addition to a range of technological applications. The heterogeneous integration of ferroelectric and ferromagnetic materials is a fruitful way to design multiferroic oxides. The realization of freestanding heterogeneous membranes of multiferroic oxides is highly desirable. In this study, epitaxial BaTiO3 /La0.7 Sr0.3 MnO3 freestanding bilayer membranes are fabricated using pulsed laser epitaxy. The membrane displays ferroelectricity and ferromagnetism above room temperature accompanying the finite magnetoelectric coupling constant. This study reveals that a freestanding heterostructure can be used to manipulate the structural and emergent properties of the membrane. In the absence of the strain caused by the substrate, the change in orbital occupancy of the magnetic layer leads to the reorientation of the magnetic easy-axis, that is, perpendicular magnetic anisotropy. These results of designing multiferroic oxide membranes open new avenues to integrate such flexible membranes for electronic applications.

7.
Clin Case Rep ; 10(7): e6133, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35898734

RESUMO

We report a case of accidental Emamectin Benzoate poisoning in a six-year-old child resulting in nausea, vomiting, abdominal pain, and confusion. We did vigorous gastric lavage with saline, activated charcoal, and coconut oil. The other supportive treatment improved the outcome of the patient with complete resolution of symptoms.

8.
Adv Sci (Weinh) ; 9(33): e2203473, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36209382

RESUMO

Actinide materials have various applications that range from nuclear energy to quantum computing. Most current efforts have focused on bulk actinide materials. Tuning functional properties by using strain engineering in epitaxial thin films is largely lacking. Using uranium dioxide (UO2 ) as a model system, in this work, the authors explore strain engineering in actinide epitaxial thin films and investigate the origin of induced ferromagnetism in an antiferromagnet UO2 . It is found that UO2+ x thin films are hypostoichiometric (x<0) with in-plane tensile strain, while they are hyperstoichiometric (x>0) with in-plane compressive strain. Different from strain engineering in non-actinide oxide thin films, the epitaxial strain in UO2 is accommodated by point defects such as vacancies and interstitials due to the low formation energy. Both epitaxial strain and strain relaxation induced point defects such as oxygen/uranium vacancies and oxygen/uranium interstitials can distort magnetic structure and result in magnetic moments. This work reveals the correlation among strain, point defects and ferromagnetism in strain engineered UO2+ x thin films and the results offer new opportunities to understand the influence of coupled order parameters on the emergent properties of many other actinide thin films.

9.
PLoS One ; 16(12): e0260638, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34932553

RESUMO

INTRODUCTION: The study aimed at exploring the adverse events following immunization (AEFI) and their incidences among health workers in three different districts of central and western Nepal following the first dose of Covishield vaccine,. It also aimed at studying the association of AEFI with demographic and clinical characteristics of vaccinees, pre-vaccination anxiety level and prior history of COVID-19 infection (RT- PCR confirmed) status. MATERIALS AND METHODS: This was a cross-sectional study carried out via face-to-face or telephonic interview among 1006 health workers one week after receiving their first dose of the Covishield vaccine. Incidence of adverse events was calculated in percentage while Chi-square Test was used to check the association of AEFI with independent variables. Logistic regression was used to find out the adjusted odd's ratio at 95% CI. RESULTS: Incidence of AEFI was 79.8% with local and systemic AEFI being 68.0% and 59.7% respectively. Injection site tenderness was the commonest manifestation. Local and systemic symptoms resolved in less than one week among 96.8% and 98.7% vaccinees respectively. Females were more likely to develop AEFI than males (AOR = 1.7, 95% CI = 1.2-2.4). Vaccinees aged 45-59 years were 50% less likely to develop AEFI as compared to those aged less than 30 years (AOR 0.5, 95% CI = 0.3-0.8). Most of the vaccinees had not undergone RT-PCR testing for COVID-19 (59.8%). Those who were not tested for COVID-19 prior were 1.5 odds more likely to develop AEFI compared to those who were negative (AOR = 1.5, 95% CI = 1.1-2.1). CONCLUSION: More than two-third of the vaccinees developed one or more forms of adverse events, but most events were self-limiting. Females and young adults were more prone to develop AEFI.


Assuntos
ChAdOx1 nCoV-19/efeitos adversos , Pessoal de Saúde/estatística & dados numéricos , Acetaminofen/farmacologia , Adulto , Idoso , COVID-19/epidemiologia , ChAdOx1 nCoV-19/administração & dosagem , Comorbidade , Estudos Transversais , Feminino , Pessoal de Saúde/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Nepal/epidemiologia , Fatores de Tempo , Vacinação/efeitos adversos , Vacinação/psicologia
10.
Nanomaterials (Basel) ; 10(10)2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33096876

RESUMO

We report on the growth of stoichiometric, single-crystal YCrO3 epitaxial thin films on (001) SrTiO3 substrates using pulsed laser deposition. X-ray diffraction and atomic force microscopy reveal that the films grew in a layer-by-layer fashion with excellent crystallinity and atomically smooth surfaces. Magnetization measurements demonstrate that the material is ferromagnetic below 144 K. The temperature dependence of dielectric permittivity shows a characteristic relaxor-ferroelectric behavior at TC = 375-408 K. A dielectric anomaly at the magnetic transition temperature indicates a close correlation between magnetic and electric order parameters in these multiferroic YCrO3 films. These findings provide guidance to synthesize rare-earth, chromite-based multifunctional heterostructures and build a foundation for future studies on the understanding of magnetoelectric effects in similar material systems.

11.
RSC Adv ; 9(23): 13033-13041, 2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35520794

RESUMO

We utilize polarized neutron reflectometry (PNR) in consort with ab initio based density functional theory (DFT) calculations to study magnetoelectric coupling at the interface of a ferroelectric PbZr0.2Ti0.8O3 (PZT) and magnetic La0.67Sr0.33MnO3 (LSMO) heterostructure grown on a Nb-doped SrTiO3 (001) substrate. Functional device working conditions are mimicked by gating the heterostructure with a Pt top electrode to apply an external electric field, which alters the magnitude and switches the direction of the ferroelectric (FE) polarization, across the PZT layer. PNR results show that the gated PZT/LSMO exhibits interfacial magnetic phase modulation attributed to ferromagnetic (FM) to A-antiferromagnetic (A-AF) phase transitions resulting from hole accumulation. When the net FE polarization points towards the interface (positive), the interface doesn't undergo a magnetic phase transition and retains its global FM ordered state. In addition to changes in the interfacial magnetic ordering, the global magnetization of LSMO increases while switching the polarization from positive to negative and decreases vice versa. DFT calculations indicate that this enhanced magnetization also correlates with an out of plane tensile strain, whereas the suppressed magnetization for positive polarization is attributed to out of plane compressive strain. These calculations also show the coexistence of FM and A-AF phases at zero out of plane strain. Charge modulations throughout the LSMO layer appear to be unaffected by strain, suggesting that these charge mediated effects do not significantly change the global magnetization. Our PNR results and DFT calculations are in consort to verify that the interfacial magnetic modulations are due to co-action of strain and charge mediated effects with the strain and charge effects dominant at different length scale.

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