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1.
Phys Chem Chem Phys ; 26(39): 25488-25500, 2024 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-39324950

RESUMEN

In this study, Eu3+ ion singly doped and Eu3+/Sm3+ ions co-doped ZnS semiconductor quantum dots (QDs) were successfully synthesized using a wet chemical method in 1-octadecene (ODE) solvent. The successful doping of Sm3+ and Eu3+ ions into the ZnS host lattice and the composition and valence of the elements present in the sample were confirmed by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Structural and morphological studies revealed the presence of Eu3+-doped ZnS and Eu3+/Sm3+ co-doped ZnS QDs of about 3-4 nm size with a zinc blende structure. The Judd-Ofelt (J-O) intensity parameters of Eu3+-doped ZnS QDs were determined from their fluorescence spectra. The optical properties of Eu3+/Sm3+ co-doped ZnS QDs were studied by changing the Eu3+ ion concentration and fixing the Sm3+ ion concentration. The photoluminescence (PL) spectra of Eu3+/Sm3+ co-doped ZnS QDs were obtained at an excitation wavelength of 403 nm (6H5/2 → 6P3/2 transition of Sm3+ ions) in the 525-725 nm range. The effective energy transfer (ET) process from Sm3+ to Eu3+ ions was confirmed and explained in detail using the Reisfeld approximation and the Inokuti-Hirayama model. The CIE color coordinates of the Eu3+/Sm3+ co-doped ZnS QDs were obtained using PL spectral data. Eu3+/Sm3+ co-doped ZnS QDs exhibited a long lifetime and emitted warm red light. These interesting properties give Eu3+/Sm3+ co-doped ZnS QDs great potential for applications in photovoltaics, photocatalysis, and biomarkers.

2.
Pediatr Cardiol ; 43(1): 82-91, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34331081

RESUMEN

Global myocardial work (GMW) is an emerging method to characterize left ventricle (LV) function with potential advantages over both ejection fraction and global longitudinal strain (GLS). We aimed to determine the feasibility and reproducibility for echocardiographic-derived GMW in a healthy pediatric population; establish normal reference values; and investigate the influence of age, gender, and other clinical factor on normal reference ranges. We prospectively enrolled 212 individuals (median age of 9 years; interquartile range, 6 to 12 years, 112 female). Global work index (GWI), global constructive work (GCW), global wasted work (GWW), and global work efficiency (GWE) were measured from LV pressure-strain loops. Quantification of GMW was performed using a GE Vivid E95 system and available software package (Echopac V.203, GE). The mean LV EF was 64 ± 3% with GLS of -21.3 ± 1.5%. GWI was 1688 ± 219 mmHg% with mean GWE of 96.5 ± 1.4%. The GCW was 1959 ± 207 mmHg%, and the mean GWW of 61.1 ± 30.9 mmHg%. No significant difference was found in MW indices across age group and gender (p > 0.05 for all). There were significant correlations between both GWI and GCW with GLS and systolic blood pressure (p < 0.001), but not with GWE and GWW. Linear regression model revealed that GWI and GCW were more closely correlated with systolic blood pressure than GLS. LV MW indices had good intra-observer and inter-observer reproducibility. This study establishes both the feasibility and reference ranges for non-invasive echocardiographic indices of GMW in healthy children. Myocardial work appears to be a complementary modality to assess LV performance in children.


Asunto(s)
Ecocardiografía , Función Ventricular Izquierda , Niño , Femenino , Humanos , Valores de Referencia , Reproducibilidad de los Resultados , Volumen Sistólico
3.
Phys Chem Chem Phys ; 23(28): 15257-15267, 2021 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-34236363

RESUMEN

Tb3+-Doped ZnSe quantum dots (QDs) with a Tb content in the range of 0.5-7% were successfully synthesized by a wet chemical method. X-Ray diffraction (XRD) and transmission electron microscopy (TEM) analyses revealed that the as-synthesized QDs had a zinc blende (ZB) structure with a particle size of approximately 4 nm. The effect of Tb-doping on the structure and optical properties of the ZnSe QDs was studied. The emission spectra and photoluminescence (PL) decay kinetics data confirmed the successful incorporation of Tb3+ ions into the ZnSe host. The PL spectra also revealed that the intensity of dopant emission was significantly enhanced owing to the energy transfer (ET) from the host emission. The efficiency of the ET process from the ZnSe host to Tb3+ ions and between Tb3+ ions and the nature of these interaction mechanisms were determined by applying the Inokuti-Hirayama and Reisfeld models. The features of the ligand field and the optical properties of Tb3+ ions in the ZnSe QDs were studied using Judd-Ofelt theory. The dependence of the chromaticity features of ZnSe:Tb3+ QDs on the Tb concentration was estimated by the chromaticity coordinates and correlated color temperature (CCT). The Tb3+-doped ZnSe QDs with visible, tunable, and very long lifetime emission have potential for practical applications such as biological labeling, photocatalysis, and white-LED devices.

4.
Phys Chem Chem Phys ; 22(11): 6266-6274, 2020 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-32129369

RESUMEN

Eu-doped CdS quantum dots (QDs) with the Eu dopant concentration in the range of 0.5-10% and zinc blende (ZB) structure were successfully synthesized by a wet chemical method. The fabricated Eu-doped CdS QDs exhibited emissions in the visible window approximately at 465, 590, 618 and 696 nm, which correspond to the excitonic emission of CdS QDs and the electronic transitions of the intra 4f6 configuration from the 5D0 level to 7F1, 7F2 and 7F4 levels of Eu3+ dopant ions, respectively. Judd-Ofelt theory was used to estimate the properties of ligand field and luminescence quantum efficiency of the material. The interaction mechanism and the efficiency of the energy transfer process from CdS QDs to Eu3+ ions were found by using Reisfeld's approximation formulas. The luminescence quenching of Eu3+-doped CdS QDs was studied through analysis of emission spectra and decay curves. The dominant interaction mechanism between Eu3+ ions and energy transfer parameters have been found by fitting the decay curves to the Inokuti-Hirayama model. The cross-relaxation channels leading to the luminescence quenching of Eu3+ have also been predicted.

5.
BMC Infect Dis ; 18(1): 603, 2018 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-30497410

RESUMEN

BACKGROUND: Diabetes mellitus (DM) is recognized as an important comorbidity for the development of tuberculosis (TB). With the increase of DM burden globally, concerns have been raised about the emerging co-epidemics of DM and TB, especially in low- and middle-income countries. METHODS: A facility-based, cross-sectional study was carried out in all 30 district TB units in Hanoi, Vietnam. All eligible, diagnosed TB patients aged 15 years old or older were asked to provide consent and were screened for diabetes using fasting blood glucose (FBG). Pre-tested semi-structured questionnaires were used for collecting demographic data, lifestyle habits and clinical data. Identification of pre-diabetes or diabetes in TB patients was done in accordance to parameters set by the American Diabetes Association (2016). RESULTS: Of 870 eligible TB patients, 831 (95.5%) participated in the study. Of those, 241 (29%; 95%CI: 25.9-32.1%) were prediabetic and 114 (13.7%; 95%CI: 11.4-16.1%) were found to have DM. The risk of DM was higher in patients belonging to the age group 40-64 years (OR 6.09; 95%CI 2.81-13.2); or the age group 65 years or older (OR 2.65; 95%CI 1.65-4.25) or who have a family history of DM (OR 2.71; 95%CI 1.33-5.50). CONCLUSIONS: This study demonstrated high prevalence of DM and prediabetes among TB patients in Hanoi, Vietnam. National Tuberculosis Programme needs to establish a systematic screening process for DM among TB patients.


Asunto(s)
Complicaciones de la Diabetes/epidemiología , Diabetes Mellitus/epidemiología , Tuberculosis/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Comorbilidad , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estado Prediabético/complicaciones , Estado Prediabético/epidemiología , Prevalencia , Factores de Riesgo , Tuberculosis/complicaciones , Vietnam/epidemiología , Adulto Joven
6.
Phys Rev Lett ; 118(11): 117201, 2017 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-28368646

RESUMEN

Spin-phonon coupling mediated by single ion anisotropy was investigated using optical spectroscopy and first-principles calculations in the all-in-all-out pyrochlore magnet Cd_{2}Os_{2}O_{7}. Clear anomalies were observed in both the phonon frequencies and linewidths at the magnetic ordering temperature. The renormalization of the phonon modes was exceptionally large, signifying the presence of an unconventional magnetoelastic term from large spin-orbit coupling. In addition, the relative phonon frequency shifts show a strong correlation with the modulation of noncubic crystal field by the corresponding lattice distortion. Our observation establishes a new type of spin-phonon coupling through single ion anisotropy, a second-order spin-orbit coupling term, in Cd_{2}Os_{2}O_{7}.

7.
J Fish Dis ; 39(5): 555-64, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26096017

RESUMEN

This study was conducted to test the effect of DnaK on priming immune responses in Penaeid shrimp. Juvenile-specific pathogen-free (SPF) P. vannamei shrimp were injected with 0.05 µg recombinant DnaK. One hour post-DnaK priming, a non-lethal dose of Vibrio campbellii (10(5) CFU shrimp(-1)) was injected. Other treatments include only DnaK or V. campbellii injection or control with blank inocula. The haemolymph of three shrimp from each treatment was collected at 1.5, 6, 9 and 12 h post-DnaK priming (hpp). It was verified that injection with DnaK and V. campbellii challenge affected the transcription of 3 immune genes, transglutaminase-1 (TGase-1), prophenoloxidase-2 (proPO-2) and endogenous HSP70 (lvHSP70). In P. monodon, shrimp were first injected with DnaK at a dose of 10 µg shrimp(-1) and one hour later with 10(6) CFU of V. harveyi (BB120) shrimp(-1). Shrimp injected with DnaK showed a significant increase in proPO expression compared to the control (P < 0.05). Yet a double injection (DnaK and Vibrio) seemed to cause an antagonistic response at the level of expression, which was not equalled at the level of PO activity. Those results suggest that DnaK is able to modulate immune responses in P. vannamei and P. monodon.


Asunto(s)
Regulación de la Expresión Génica/efectos de los fármacos , Proteínas HSP70 de Choque Térmico/farmacología , Penaeidae/efectos de los fármacos , Animales , Catecol Oxidasa/genética , Precursores Enzimáticos/genética , Regulación de la Expresión Génica/inmunología , Proteínas HSP70 de Choque Térmico/genética , Sistema Inmunológico/efectos de los fármacos , Factores Inmunológicos/farmacología , Penaeidae/inmunología , Penaeidae/microbiología , Organismos Libres de Patógenos Específicos , Transglutaminasas/genética , Vibrio/inmunología
8.
RSC Adv ; 14(6): 3712-3722, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38268546

RESUMEN

In this study, Er-doped CoAl2O4 nanocrystals (NCs) were synthesized via co-precipitation. All the NCs were crystallized in the form of a single phase with a spinel structure and Er3+ ions replaced Al3+ ions in the formation of the CoAl2-xErxO4 alloy structure. The optical characteristics of the Er3+ ion-doped CoAl2O4 NCs were thoroughly investigated by analyzing both the UV-VIS and photoluminescence spectra, using the Judd-Ofelt theory. The effect of Er doping content on the luminescent properties of the CoAl2O4 pigment (using lasers emitting at wavelengths of 413 and 978 nm) has been studied. The values of Judd-Oflet intensity parameters (Ω2, Ω4, and Ω6) were determined from the absorption spectra using the least square fitting method. The J-O parameters were calculated and compared with those of other host materials; the values of the Ω2, Ω4, and Ω6 parameters decreased with an increase in Er concentration. This suggests that the rigidity and local symmetry of the host materials become weaker as the concentration of Er3+ ions increases. The highest value of the Ω2 parameter, when compared with Ω4 and Ω6, suggests that the vibrational frequencies in the given samples are relatively low. The upconversion fluorescence phenomenon was observed and explained in detail under an excitation wavelength of 978 nm when the excitation power was varied.

9.
Nanoscale Adv ; 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39263250

RESUMEN

CoAl2O4:xDy3+ nanocrystals (x = 0, 0.1, 0.5, 1.0, and 3.0 mol%) with spinel structures were prepared using the co-precipitation method. The crystal structure, optical properties, and presence of elements were respectively analyzed using X-ray diffraction, photoluminescence excitation, photoluminescence spectra, luminescence lifetime, and X-ray photoelectron spectroscopy. The influence of temperature on material fabrication was studied using differential scanning calorimetry and thermogravimetric techniques. The color characteristics of Dy3+ luminescence in the CoAl2O4 host were evaluated using CIE chromaticity coordinates and correlated color temperature. For the first time, the electronic dipole transitions in the photoluminescence excitation spectra were used to calculate the optical parameters of Dy3+ ions in the CoAl2O4 host using Judd-Ofelt theory. The Inokuti-Hirayama model was used to explain the energy transfer process between Dy3+ ions, the main interaction mechanism, and energy transfer parameters for the luminescence of Dy3+ ions.

10.
J Nerv Ment Dis ; 201(5): 429-34, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23595097

RESUMEN

A partial hospitalization program was developed for youth with moderate to severe psychiatric disorders. The objectives of this study were to prospectively assess changes from admission to discharge in the participants' clinical symptoms and psychosocial functioning, as well as the maintenance of any treatment gains at 3-month follow-up. In this naturalistic treatment study, 55 youth completed both the youth partial hospitalization program and the study. Diagnosis at admission was established by a psychiatrist based on a clinical assessment and a structured diagnostic interview. Clinician-rated and self-report measures of symptoms and psychosocial functioning were administered at admission, discharge, and follow-up to track changes over time. Clinically and statistically significant improvements were found in both symptoms and psychosocial functioning from admission to discharge on all study measures. Furthermore, these gains were maintained at 3-month follow-up. The results suggest that partial hospitalization programs can be an effective modality in treating youth with moderate to severe psychiatric disorders.


Asunto(s)
Centros de Día/métodos , Trastornos Mentales/terapia , Adolescente , Centros de Día/psicología , Femenino , Estudios de Seguimiento , Humanos , Entrevista Psicológica , Masculino , Alta del Paciente , Estudios Prospectivos , Escalas de Valoración Psiquiátrica , Pruebas Psicológicas , Ajuste Social , Resultado del Tratamiento , Adulto Joven
11.
J Adolesc ; 36(6): 1013-24, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24215948

RESUMEN

Normative romantic development is theorized to progress through a series of stages: affiliative activities, group-based dating, and romantic relationships. The objectives of this research were threefold: empirically examine this progression of romantic stages during adolescence, determine normative and atypical trajectories, and examine links with internalizing and externalizing symptoms. An eight-wave longitudinal study was conducted with 698 adolescents (53.6% female; M(age) = 11.8 years at start of study). A group-based trajectory approach was employed to identify prototypical trajectories of romantic development and a model with three distinct romantic trajectories (i.e., On-time, Early Starters and Late Bloomers) was identified. Both timing and sequencing of romantic activity differed among trajectory groups. Analysis of Variance (ANOVAs) identified associations between Early Starters and externalizing behaviours in early, middle and later adolescence. The findings support progression through theorized stages of romantic activity and highlight the problems that are linked to early-starting and non-sequenced romantic development.


Asunto(s)
Conducta del Adolescente , Desarrollo del Adolescente , Cortejo/psicología , Adolescente , Análisis de Varianza , Canadá , Niño , Femenino , Humanos , Control Interno-Externo , Estudios Longitudinales , Masculino , Modelos Teóricos , Encuestas y Cuestionarios , Adulto Joven
12.
RSC Adv ; 13(39): 27292-27302, 2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37705985

RESUMEN

In this study, Er3+ doped ZnO semiconductor quantum dots (QDs) were synthesized using a wet chemical method. The successful doping of Er3+ ions into the ZnO host lattice and the elemental composition was confirmed by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The ZnO and Er3+ doped ZnO QDs with a hexagonal structure, spherical shape, and particle size of approximately 5 nm were revealed by XRD and transmission electron microscopy (TEM). The absorption, luminescence properties, and fluorescence lifetimes of the samples were studied as the concentration of Er3+ ions varied. The intensity parameters, emission transition probabilities, branching ratios, and emission lifetimes of the excited levels of Er3+ ions in the ZnO host were determined using the Judd-Ofelt theory, which provided insight into the covalent relationship between the ions and ligands as well as the nature of the ZnO host lattice. Moreover, the energy transfer process from the ZnO host to Er3+ ions and the yield of this process are explained in detail along with specific calculations. The Er3+ doped ZnO QDs displayed a significantly longer lifetime than undoped ZnO, which opens up many potential applications in fields such as photocatalysis, optoelectronics, photovoltaics, and biosensing.

13.
RSC Adv ; 13(51): 36455-36466, 2023 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-38099261

RESUMEN

In this study, CdTexSe1-x (0 ≤ x ≤ 1) and CdTeSe:Gd y% (y = 0-8.05) alloy semiconductor nanocrystals (NCs) were prepared by wet chemical method. The presence and composition of the elements in the sample were determined by energy dispersive X-ray (EDX) spectroscopy and X-ray photoelectron spectroscopy (XPS). Structural analysis of X-ray diffraction (XRD) patterns indicated that most NCs crystallized in the zinc blende (ZB) structure however some Gd-doped NCs (y = 4.52 and 8.05%) crystallized in the wurtzite (WZ) structure. The emission peak of CdTexSe1-x (0 ≤ x ≤ 1) NCs varied over a wide range when changing x while the particle size remained almost unchanged. The effect of Gd doping on the structure and optical and magnetic properties of CdTeSe NCs was studied in detail. When the Gd concentration increases from 0-8.05%: (i) the structure of CdTeSe NCs gradually changed from ZB to WZ, (ii) the emission efficiency of the material was significantly reduced, (iii) the PL lifetime of samples increased more than 10 times, and (iv) the ferromagnetic properties of the material were enhanced. The research findings demonstrated that it is possible to control the crystal structure, optical characteristics, and magnetic properties of Gd-doped CdTeSe nanocrystals by adjusting the dopant concentration and chemical composition of the host material.

14.
RSC Adv ; 11(14): 7961-7971, 2021 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-35423296

RESUMEN

The role of samarium (Sm) dopant on the structural, morphological, and optical properties of CdS QDs and CdS/ZnS core/shell QDs was methodically reported. The synthesis of Sm-doped CdS QDs and CdS/ZnS QDs was carried out via a facile wet chemical method. The structure, chemical composition, and optical properties of the synthesized QDs were investigated by using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy (RS), and photoluminescence (PL) spectroscopy. XRD analysis showed that the synthesized CdS QDs exhibited zinc blende structure which was not affected by doping Sm3+ ions. The particle size of the CdS:Sm and CdS:Sm (2%)/ZnS QDs was estimated to be ∼4 nm and ∼7 nm, respectively. Transmission electron microscopy (TEM) images revealed that the incorporation of Sm dopant did not significantly affect the size and morphology of CdS QDs, while the formation of the ZnS shell increased the particle size. XPS and XRD results confirmed the successful incorporation of Sm3+ ions into the CdS QDs. The effect of dopant concentration on the structural and luminescent properties was studied. The emission and excitation spectra of Sm3+-doped CdS QDs and CdS/ZnS QDs consisted of the characteristic lines corresponding to the intra-configurational f-f transitions. The energy transfer (ET) mechanism from the host to Sm3+ ions and the ET process through cross-relaxation between Sm3+ ions have been elucidated. The effect of the ZnS shell on the optical stability of the Sm3+-doped CdS QDs was studied in detail and the results showed that the CdS:Sm (2%)/ZnS QDs retained their good emission characteristics after 376 days of fabrication. The luminescent properties of Sm-doped QDs ranging from violet to red and PL lifetime extending to milliseconds demonstrated that these QDs are the potential materials for applications in white LEDs, biomarkers, and photocatalysis.

15.
J Intern Med ; 268(2): 181-93, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20497296

RESUMEN

OBJECTIVES: Interleukin (IL)-7 is a key cytokine in T-cell homeostasis. Stromal cells, intestinal epithelial cells and keratinocytes are known to produce this cytokine. The mechanisms and cellular factors regulating IL-7 production are still unclear. We assessed whether IL-1beta and interferon (IFN)-gamma, cytokines produced during inflammatory conditions, may impact on IL-7 production. DESIGN: We used human intestinal epithelial cells (DLD-1 cell line) and bone marrow stromal cells (HS27 cell line), known to produce IL-7; IL-7 production was evaluated at the mRNA and protein levels. To assess whether treatment of HS27 cells with IL-1beta and/or IFN-gamma leads to changes in the gene expression of cytokines, Toll-like receptors (TLRs) and chemokines, we analysed gene expression profiles using the whole-genome microarray Human Gene 1.0 ST. RESULTS: We found that IFN-gamma enhanced the expression of IL-7 mRNA (P < 0.001) in both cell lines. IL-1beta treatment led to a significant down-regulation (P < 0.001) of IL-7 mRNA expression in both cell lines. The IL-7 concentration in supernatants collected from treated DLD-1 and HS27 cell cultures reflected the trend of IL-7 mRNA levels. The gene profiles revealed dramatic changes in expression of cytokines and their receptors (IL-7/IL-7R alpha; IL-1alpha,IL-1beta/IL-1R1; IFN-gamma/IFN-gammaR1), of IFN regulatory factors (IRF-1 and 2), of TLRs and of important chemo-attractants for T cells. The microarray results were verified by additional methods. CONCLUSIONS: Our results are discussed in the setting of inflammation and T-cell survival in the gut compartment during HIV-1 infection where stromal and epithelial cells may produce factors that contribute to impaired IL-7 homeostasis and homing of T cells.


Asunto(s)
Infecciones por VIH/inmunología , VIH-1 , Interleucina-1beta/inmunología , Interleucina-7/biosíntesis , Linfocitos T/inmunología , Apoptosis/inmunología , Células de la Médula Ósea/inmunología , Citocinas/inmunología , Células Epiteliales/inmunología , Perfilación de la Expresión Génica/métodos , Regulación de la Expresión Génica/inmunología , Humanos , Inmunidad Mucosa , Interferón gamma/inmunología , Interleucina-7/genética , Modelos Inmunológicos , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , ARN Mensajero/genética , Receptores de Quimiocina/metabolismo , Células del Estroma/inmunología , Células Tumorales Cultivadas , Receptor fas/metabolismo
16.
Epidemiol Infect ; 138(11): 1550-8, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20236573

RESUMEN

The apparent family clustering of avian influenza A/H5N1 has led several groups to postulate the existence of a host genetic influence on susceptibility to A/H5N1, yet the role of host factors on the risk of A/H5N1 disease has received remarkably little attention compared to the efforts focused on viral factors. We examined the epidemiological patterns of human A/H5N1 cases, their possible explanations, and the plausibility of a host genetic effect on susceptibility to A/H5N1 infection. The preponderance of familial clustering of cases and the relative lack of non-familial clusters, the occurrence of related cases separated by time and place, and the paucity of cases in some highly exposed groups such as poultry cullers, are consistent with a host genetic effect. Animal models support the biological plausibility of genetic susceptibility to A/H5N1. Although the evidence is circumstantial, host genetic factors are a parsimonious explanation for the unusual epidemiology of human A/H5N1 cases and warrant further investigation.


Asunto(s)
Predisposición Genética a la Enfermedad , Subtipo H5N1 del Virus de la Influenza A , Gripe Humana/genética , Gripe Humana/virología , Análisis por Conglomerados , Humanos , Gripe Humana/transmisión , Linaje , Factores de Riesgo
17.
RSC Adv ; 10(20): 11957-11965, 2020 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-35496597

RESUMEN

We investigated the effects of Mn doping on the crystal structure, phonon vibration, and magnetic properties of Bi0.88Sm0.12FeO3 ceramics. Mn doping effectively modified the rhombohedral symmetry and induced a structural transition from an R3c rhombohedral to Pnam orthorhombic structure. Magnetic measurements revealed a weak ferromagnetic behavior, which was related to the canted antiferromagnetic order of the Pnam structure. The cycloidal spin structure of the R3c phase could not be suppressed by substitution of Mn at the Fe site. Studies on the self-phase transition and electric field-induced structural transition revealed many changes in coercivity and remanent magnetization, which are believed to originate from the R3c/Pnam phase switching along with spin frustration. Observations of the field step-dependent hysteresis loop and the ferromagnetic-like hysteresis loop after poling in an electric field provided direct evidence of phase boundary (PB) ferromagnetism and magnetic coupling at the PB.

18.
RSC Adv ; 10(43): 25618-25628, 2020 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-35518601

RESUMEN

Tunable copper doped Zn1-x Cd x S alloy quantum dots (QDs) were successfully synthesized by the wet chemical method. A one-step method is developed to synthesize doped ternary QDs which is more preferable than a two-step method. The influence of experimental parameters like the Zn/Cd ratio and Cu dopant concentration has been investigated using various spectroscopic techniques like UV-visible, photoluminescence, X-ray diffraction and Raman spectroscopy. The absorption and emission properties can be tuned by changing the concentration of components of the ternary QDs. The high concentration of dopant completely quenched the emission of the ternary QDs. EDX gives confirmation of the elemental composition of the synthesized samples. The obtained results suggest the successful doping of the ternary QDs. Interestingly, the study results revealed that the crystal structure (ZB and/or WZ) and the dual emission of the Cu-doped Zn1-x Cd x Se alloy QDs could be controlled by varying the dopant concentration and chemical composition of the host. Doping also leads to enhancement in emission properties and provides more stability to ternary QDs. The enhancement in the photoluminescence (PL) decay lifetime of Cu-doped ternary QDs can be advantageous for optoelectronic and biosensor applications.

19.
J Am Acad Child Adolesc Psychiatry ; 54(5): 403-411.e2, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25901777

RESUMEN

OBJECTIVE: To estimate jointly the point prevalence of weight and eating disorders in a community sample of adolescents; to investigate psychosocial correlates of thinness, overweight, and obesity, and of full- and subthreshold eating disorders (EDs); and to examine the relationships between weight status and prevalence of EDs. METHOD: A total of 3,043 Canadian adolescents (1,254 males and 1,789 females; mean age = 14.19 years, SD = 1.61 years) completed self-report questionnaires, including the Eating Disorder Diagnostic Scale, and measures of psychosocial functioning. Objective weight and height were collected, and weight status was defined according to the International Obesity Task Force body mass index growth curve centiles. RESULTS: In all, 29.5% (95% CI = 26.7, 32.5) of males and 22.8% (95% CI = 20.5, 25.2) of females were overweight or obese. A total of 2.2% (95% CI = 1.5, 3.2) of males and 4.5% (95% CI = 4.4, 4.5) of females met DSM-5 criteria for an ED; in addition, 1.1% (95% CI = 0.7, 1.9) of males and 5.1% (95% CI = 4.0, 6.5) of females were identified with a subthreshold ED. Both full- and subthreshold EDs were significantly associated with markedly impaired psychosocial functioning. There was a significant relationship between prevalence of EDs and weight status, with an increased risk for a bulimic disorder in obese relative to normal-weight males (odds ratio [OR] = 7.86) and females (OR = 3.27). CONCLUSION: This study provides estimates for the prevalence of DSM-5 EDs in adolescents, further support for their impact on mental health, and new evidence for an association between bulimic disorders and obesity. Results call for an integrated approach in research and prevention regarding the whole spectrum of eating- and weight-related disorders.


Asunto(s)
Imagen Corporal/psicología , Índice de Masa Corporal , Trastornos de Alimentación y de la Ingestión de Alimentos/diagnóstico , Trastornos de Alimentación y de la Ingestión de Alimentos/epidemiología , Obesidad/epidemiología , Sobrepeso/epidemiología , Adolescente , Niño , Femenino , Humanos , Masculino , Salud Mental , Oportunidad Relativa , Ontario , Instituciones Académicas , Autoinforme , Adulto Joven
20.
Arch Dermatol ; 124(6): 903-6, 1988 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3377519

RESUMEN

Fifty-eight patients participated in a controlled evaluation that compared a transparent film dressing (TFD [Bioclusive]) with a combination of conventional dry gauze dressing (Curity) and antibiotic ointment (Polysporin) in the treatment of fresh skin wounds following Mohs micrographic surgery. The TFD group showed a faster rate of wound contraction and reepithelialization and a shorter total healing time. The TFD was rated better with regard to comfort, ease of use, and ease of dressing removal. At six-month follow-up, the TFD group had scars that were softer, smoother, and showed less thickening and anatomic deformities. Better cosmetic appearance and greater patient acceptance were also noted with the TFD.


Asunto(s)
Procedimientos Quirúrgicos Dermatologicos , Apósitos Oclusivos , Cicatrización de Heridas , Compuestos de Zinc , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/administración & dosificación , Vendajes , Carcinoma Basocelular/cirugía , Carcinoma de Células Escamosas/cirugía , Cloruros/administración & dosificación , Neoplasias Faciales/cirugía , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Pomadas , Cuero Cabelludo , Neoplasias Cutáneas/cirugía , Zinc/administración & dosificación
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