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1.
ACS Appl Mater Interfaces ; 15(34): 40459-40468, 2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37589336

RESUMEN

Deuterium (D2(g)) storage of Pd-coated Ti ultra-thin films at relatively low pressures is fine-tuned by systematically controlling the thicknesses of the catalytic Pd overlayer, underlying Ti ultra-thin film domain, D2(g) pressure (PD2), duration of D2(g) exposure, and the thin film temperature. Structural properties of the Ti/Pd nanofilms are investigated via XRD, XPS, AFM, SEM, and TPD to explore new structure-functionality relationships. Ti/Pd thin film systems are deuterated to obtain a D/Ti ratio of up to 1.53 forming crystallographically ordered titanium deuteride (TiDx) phases with strong Tix+-Dy- electronic interactions and high thermal stability, where >90% of the stored D resides in the Ti component, thermally desorbing at >460 °C in the form of D2(g). Electronic interaction between Pd and D is weak, yielding metallic (Pd0) states where D storage occurs mostly on the Pd film surface (i.e., without forming ordered bulk PdDx phases) leading to the thermal desorption of primarily DOH(g) and D2O(g) at <265 °C. D-storage typically increases with increasing Ti film thickness, PD2, T, and t, whereas D-storage is found to be sensitive to the thickness and the surface roughness of the catalytic Pd overlayer. Optimum Pd film thickness is determined to be 10 nm providing sufficient surface coverage for adequate wetting of the underlying Ti film while offering an appropriate number of surface defects (roughness) for D immobilization and a relatively short transport pathlength for efficient D diffusion from Pd to Ti. The currently used D-storage optimization strategy is also extended to a realistic tritium-based betavoltaic battery (BVB) device producing promising ß-particle emission yields of 164 mCi/cm2, an open circuit potential (VOC) of 2.04 V, and a short circuit current (ISC) of 7.2 nA.

2.
J Neurosci Rural Pract ; 14(2): 224-229, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37181197

RESUMEN

Objectives: Data are limited regarding the relationship of neutrophil/lymphocyte ratio (NLR), monocyte/lymphocyte ratio (MLR), and platelet/ lymphocyte ratio (PLR) with neurological symptoms (NS) in COVID-19 patients. This study is the first to assess the utility of the NLR, MLR, and PLR for predicting COVID-19 severity in infected patients with NS. Materials and Methods: Consecutive 192 PCR-positive COVID-19 patients with NS were included in this cross-sectional and prospective study. The patients were classified into the non-severe and severe groups. We analyzed routinely complete blood count in these groups in terms of COVID-19 disease severity. Results: Advanced age, a higher body mass index, and comorbidities were significantly more common in the severe group (P < 0.001). Among the NS, anosmia (P = 0.001) and memory loss (P = 0.041) were significantly more common in the non-severe group. In the severe group, the lymphocytes and monocyte counts and the hemoglobin level were significantly lower, while the neutrophil count, NLR, and PLR were significantly higher (all P < 0.001). In the multivariate model, advanced age and a higher neutrophil count were independently associated with severe disease (both P < 0.001) but the NLR and PLR were not (both P > 0.05). Conclusion: We found positive associations of COVID-19 severity with the NLR and PLR in infected patients with NS. Further research is required to shed more light on the role of neurological involvement in disease prognosis and outcomes.

3.
Chemphyschem ; 24(13): e202200787, 2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37104548

RESUMEN

Understanding the activation of CO2 on the surface of the heterogeneous catalysts comprised of metal/metal oxide interfaces is of critical importance since it is not only a prerequisite for converting CO2 to value-added chemicals but also often, a rate-limiting step. In this context, our current work focuses on the interaction of CO2 with heterogeneous bi-component model catalysts consisting of small MnOx clusters supported on the Pd(111) single crystal surface. These metal oxide-on-metal 'reverse' model catalyst architectures were investigated via temperature programmed desorption (TPD) and x-ray photoelectron spectroscopy (XPS) techniques under ultra-high vacuum (UHV) conditions. Enhancement of CO2 activation was observed upon decreasing the size of MnOx nanoclusters by lowering the preparation temperature of the catalyst down to 85 K. Neither pristine Pd(111) single crystal surface nor thick (multilayer) MnOx overlayers on Pd(111) were not capable of activating CO2 , while CO2 activation was detected at sub-monolayer (∼0.7 ML) MnOx coverages on Pd(111), in correlation with the interfacial character of the active sites, involving both MnOx and adjacent Pd atoms.

4.
J Med Virol ; 95(1): e28240, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36262025

RESUMEN

A wide spectrum of neurological symptoms (NS) has been described in patients with COVID-19. We examined the plasma levels of neuron-specific enolase (NSE) and neurofilament light chain (NFL) together, as neuronal damage markers, and their relationships with clinical severity in patients with NS at acute COVID-19. A total of 20 healthy controls and 59 patients with confirmed COVID-19 were enrolled in this pilot prospective study. Serum NSE and NFL levels were measured by using the enzyme-linked immunoassay method from serum samples. Serum NSE levels were found to be significantly higher in the severe group than in the nonsevere group (p = 0.034). However, serum NFL levels were similar between the control and disease groups (p > 0.05). For the mild group, serum NFL levels were significantly higher in patients with the sampling time ≥5 days than in those with the sampling time <5 days (p = 0.019). However, no significant results for NSE and NFL were obtained in patients with either single or multiple NS across the groups (p > 0.05). Increased serum NSE levels were associated with disease severity regardless of accompanied NS in patients with acute COVID-19 infection. However, serum NFL levels may have a role at the subacute phase of COVID-19.


Asunto(s)
COVID-19 , Humanos , Proyectos Piloto , Estudios Prospectivos , Biomarcadores , Técnicas para Inmunoenzimas
5.
J Am Chem Soc ; 144(19): 8848-8860, 2022 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-35486918

RESUMEN

Fundamental understanding of catalytic deactivation phenomena such as sulfur poisoning occurring on metal/metal-oxide interfaces is essential for the development of high-performance heterogeneous catalysts with extended lifetimes. Unambiguous identification of catalytic poisoning species requires experimental methods simultaneously delivering accurate information regarding adsorption sites and adsorption geometries of adsorbates with nanometer-scale spatial resolution, as well as their detailed chemical structure and surface functional groups. However, to date, it has not been possible to study catalytic sulfur poisoning of metal/metal-oxide interfaces at the nanometer scale without sacrificing chemical definition. Here, we demonstrate that near-field nano-infrared spectroscopy can effectively identify the chemical nature, adsorption sites, and adsorption geometries of sulfur-based catalytic poisons on a Pd(nanodisk)/Al2O3 (thin-film) planar model catalyst surface at the nanometer scale. The current results reveal striking variations in the nature of sulfate species from one nanoparticle to another, vast alterations of sulfur poisoning on a single Pd nanoparticle as well as at the assortment of sulfate species at the active metal-metal-oxide support interfacial sites. These findings provide critical molecular-level insights crucial for the development of long-lifetime precious metal catalysts resistant toward deactivation by sulfur.


Asunto(s)
Óxidos , Azufre , Catálisis , Óxidos/química , Análisis Espectral , Sulfatos , Azufre/química
6.
Photodiagnosis Photodyn Ther ; 38: 102823, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35331956

RESUMEN

BACKGROUND: To evaluate the choroidal structural changes in multiple sclerosis (MS) patients without previous optic neuritis (ON) attacks. METHODS: Forty eyes of 20 MS patients without a history of ON and 40 eyes of 20 age-matched healthy volunteers were included in this study. The choroidal thickness (CT) was measured at three points; subfoveal, 1500 µm nasal to the fovea, and 1500 µm temporal to the fovea. Choroidal area (CA), luminal area (LA), and choroidal vascularity index (CVI) were calculated using ImageJ. RESULTS: The mean subfoveal, nasal and temporal CT were decreased in MS patients compared to controls (for all, p < 0.001). The mean LA was 0.572 ± 0.113 mm2 in MS group, and 0.729 ± 0.188 mm2 in controls (p = 0.002). The mean CVI was decreased in the MS group (69.38% ± 4.87) in comparison to the controls (73.41% ± 5.18) (p = 0.034). CONCLUSION: The current study demonstrated significant anatomical alterations of the choroid in the eyes of patients with MS.


Asunto(s)
Esclerosis Múltiple , Neuritis Óptica , Fotoquimioterapia , Coroides/diagnóstico por imagen , Humanos , Esclerosis Múltiple/diagnóstico por imagen , Neuritis Óptica/diagnóstico por imagen , Fotoquimioterapia/métodos , Tomografía de Coherencia Óptica
7.
Photodiagnosis Photodyn Ther ; 36: 102531, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34520878

RESUMEN

PURPOSE: To evaluate the choroidal structural parameters, peripapillary retinal nerve fiber layer (RNFL) thickness, and optic density index (ODI) and their correlations in patients with migraine. METHODS: Twenty-eight newly diagnosed migraine patients and 28 age-matched healthy controls were included in this prospective cross-sectional study. The enhanced depth-optical coherence tomography images were evaluated. The choroidal area (CA) was binarized to the luminal area (LA) and stromal area (SA) using Image J. The choroidal vascularity index (CVI), the mean peripapillary RNFL thickness, superior-inferior-nasal-temporal quadrant RNFL thicknesses, and the ODI were compared statistically. RESULTS: The difference in the mean CVI between the patient group and controls reached a statistical significance (p=0.035). The mean RNFL thickness was significantly decreased in patients with migraine compared with the controls (p=0.040). The mean RNFL thickness in the superior, temporal, and inferior quadrants was significantly decreased in the patient group in comparison to the control subjects (p=0.030, p=0.001, and p=0.022, respectively). There were no significant differences between the migraine group and the controls for the mean ODI of RNFL (p=0.399). CONCLUSION: The CVI and the RNFL thickness except for the nasal quadrant were significantly decreased in newly diagnosed migraine patients.


Asunto(s)
Trastornos Migrañosos , Fotoquimioterapia , Estudios Transversales , Humanos , Trastornos Migrañosos/diagnóstico por imagen , Fibras Nerviosas , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes , Estudios Prospectivos , Células Ganglionares de la Retina , Tomografía de Coherencia Óptica
8.
ACS Appl Mater Interfaces ; 13(4): 5099-5110, 2021 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-33492925

RESUMEN

In this article, we describe the development of a new aerobic C-H oxidation methodology catalyzed by a precious metal-free LaMnO3 perovskite catalyst. Molecular oxygen is used as the sole oxidant in this approach, obviating the need for other expensive and/or environmentally hazardous stoichiometric oxidants. The electronic and structural properties of the LaMnO3 catalysts were systematically optimized, and a reductive pretreatment protocol was proved to be essential for acquiring the observed high catalytic activities. It is demonstrated that this newly developed method was extremely effective for the oxidation of alkylarenes to ketones as well as for the oxidative dimerization of 2-naphthol to 1,1-binaphthyl-2,2-diol (BINOL), a particularly important scaffold for asymmetric catalysis. Detailed spectroscopic and mechanistic studies provided valuable insights into the structural aspects of the active catalyst and the reaction mechanism.

9.
ACS Appl Mater Interfaces ; 12(40): 45136-45144, 2020 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-32896125

RESUMEN

Copper nanowires (Cu NWs) hold promise as they possess equivalent intrinsic electrical conductivity and optical transparency to silver nanowires (Ag NWs) and cost substantially less. However, poor resistance to oxidation is the historical challenge that has prevented the large-scale industrial utilization of Cu NWs. Here, we use benzotriazole (BTA), an organic corrosion inhibitor, to passivate Cu NW networks. The stability of BTA-passivated networks under various environmental conditions was monitored and compared to that of bare Cu NW control samples. BTA passivation greatly enhanced the stability of networks without deteriorating their optoelectronic performance. Moreover, to demonstrate their potential, BTA-passivated networks were successfully utilized in the fabrication of a flexible capacitive tactile sensor. This passivation strategy has a strong potential to pave the way for large-scale utilization of Cu NW networks in optoelectronic devices.

10.
ACS Appl Mater Interfaces ; 12(13): 15785-15792, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32176470

RESUMEN

Large area 2D WS2 has been grown successfully by radio frequency magnetron sputtering (RFMS) method. First, in order to investigate the pressure dependence on the grown WS2 samples, WS2 were grown at 5 different growth pressures, 5, 10, 15, 20, and 25 mTorr. It has been observed that the surface morphology changes for the samples grown at higher growth pressures, 15, 20, and 25 mTorr. Vertically standing nanowall (NW)-like structures have been formed at these relatively high growth pressures. It has also been observed that the (002) plane is highly dominant, which means layer by layer growth parallel to the substrate, for the sample grown at 20 mTorr. X-ray photoelectron spectroscopy (XPS) measurements revealed an increasing atomic percentage of the S element to W element, S/W, ratio in thin films, as the growth pressure increases. Growth dynamics of WS2 has been investigated by time-dependent-growth WS2 samples, 5, 10, 20, 40, and 80 s under 20 mTorr pressure. It has been shown by atomic force microscopy, scanning electron microscopy, and transmission electron microscopy that a highly smooth surface has been achieved in the samples grown for the duration of 5 and 10 s. Raman mapping measurements on the sample grown at 5 s have revealed large area homogeneous growth. As the growth time gets longer, the NWs emerge on the surface at some nucleation points. Only the peak that belongs to the (002) plane has been observed for samples grown at 5 and 10 s by the X-ray diffraction (XRD) measurements. XRD measurements have revealed the appearance of turbostratic peaks of (11l) and (10l) as the thickness increases. Photoluminescence measurements have indicated near-band-edge emission centered at 630 nm for only 5 and 10 s samples.

11.
Top Stroke Rehabil ; 26(5): 373-381, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31032715

RESUMEN

Background: There is no Turkish version of the Postural Assessment Scale for Stroke patients (PASS). Objectives: To translate and make the cross-cultural adaptation of the PASS into the Turkish language and evaluate the reliability and validity of the Turkish version (PASS-Turk). Methods: Sixty patients with stroke who had survived the three-week acute period were included in the study. The first researcher applied the scale to the participants twice with 5-day intervals. The second researcher applied the scale once at the same time with the first researcher. The reliability of PASS-Turk and its subsections was evaluated using Cronbach's alpha coefficient. In addition, item-total correlation and test-retest reliability were calculated. The interobserver agreement was assessed using the intraclass correlation coefficient. The construct validity of PASS-Turk was assessed using Pearson's product-moment correlation and principal component analyses. The Berg Balance Scale (BBS) and motor subscale of the Functional Independence Measure (FIM) were used for validity. Results: The Cronbach's alpha coefficients of the PASS-Turk scale were 0.903 for the subsection of "maintaining posture," 0.940 for the subsection of "changing a posture," and 0.953 for the total PASS-Turk scale. The first and second researcher evaluations were perfectly consistent with each other in terms of PASS-Turk total scores (ICC = 0.999, 95% CI: 0.998-0.999, and p < .001). A strong positive correlation was found between PASS-Turk and BBS and the motor subscale of FIM. Conclusion: PASS-Turk is a valid and reliable scale for the evaluation of posture and balance of patients with stroke.


Asunto(s)
Técnicas de Diagnóstico Neurológico/normas , Equilibrio Postural/fisiología , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/fisiopatología , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Accidente Cerebrovascular/diagnóstico , Turquía
12.
ACS Appl Mater Interfaces ; 11(1): 865-879, 2019 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-30525435

RESUMEN

Composite systems of P25 (titania) functionalized with thioglycolic acid (TGA)-capped CdTe colloidal quantum dots (QDs) were synthesized, structurally characterized, and photocatalytically tested in the photocatalytic NO x oxidation and storage during NO(g) + O2(g) reaction. Pure P25 yielded moderate-to-high NO conversion (31% in UV-A and 40% in visible (vis)) but exhibited extremely poor selectivity toward NO x storage in solid state (25% in UV-A and 35% in vis). Therefore, P25 could efficiently photooxidize NO(g) + O2(g) into NO2; however, it failed to store photogenerated NO2 and released toxic NO2(g) to the atmosphere. CdTe QD-functionalized P25 revealed a major boost in photocatalytic performance with respect to pure P25, where NO conversion reached 42% under UV-A and 43% under vis illumination, while the respective selectivity climbed up to 92 and 97%, rendering the CdTe/P25 composite system an efficient broad-band photocatalyst, which can harvest both UV-A and vis light efficiently and display a strong NO x abatement effect. Control experiments suggested that photocatalytic active sites responsible for the NO(g) + O2(g) photooxidation and formation of NO2 reside mostly on titania, while the main functions of the TGA capping agent and the CdTe QDs are associated with the photocatalytic conversion of the generated NO2 to the adsorbed NO x species, significantly boosting the selectivity toward solid-state NO x storage. Reuse experiments showed that photocatalytic performance of the CdTe/P25 system can be preserved to a reasonable extent with only a moderate decrease in the photocatalytic performance. Although some decrease in the photocatalytic activity was observed after aging, CdTe/P25 could still outperform P25 benchmark photocatalyst. Increasing CdTe QDs loading from the currently optimized minuscule concentrations could be a useful strategy to increase further the catalytic lifetime/stability of the CdTe/P25 system with only a minor penalty in catalytic activity.

14.
Anaesth Intensive Care ; 40(1): 131-6, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22313073

RESUMEN

Assessment of the severity of unconsciousness in patients with impaired consciousness, prediction of mortality and prognosis are currently the most studied subjects in intensive care. The aim of this study was to investigate the usefulness of the Full Outline of UnResponsiveness (FOUR) score in intensive care unit patients with stroke and the associations of FOUR score with the clinical outcome and with other coma scales (Glasgow [GCS] and Acute Physiology and Chronic Health Evaluation II). One hundred acute stroke patients (44 male, 56 female), who were followed in a neurology intensive care unit, were included in this prospective study. The mean age of the patients was 70.49 ± 12.42 years. Lesion types were determined as haemorrhagic in 30 and ischaemic in 70 patients. FOUR scores on the day of admission and the first, third and 10th days of patients who died within 15 days were lower when compared to scores of patients who survived (P=0.005, P=0.000, P=0.000 and P=0.000 respectively). Receiver operating characteristic curve analysis showed significant trending with both FOUR score and GCS for prognosis; the area under curve ranged from 0.675 (95% confidence interval 0.565 to 0.786) when measurements had been made on day 3 to 0.922 (95% confidence interval 0.867 to 0.977) and 0.981 (95% confidence interval 0.947 to 1.015) for day 10. We suggest that FOUR score is a useful scale for evaluation of acute stroke patients in the intensive care unit as a homogeneous group, with respect to the outcome estimation.


Asunto(s)
Coma/diagnóstico , Accidente Cerebrovascular/diagnóstico , Índices de Gravedad del Trauma , Anciano , Anciano de 80 o más Años , Isquemia Encefálica/fisiopatología , Hemorragia Cerebral/fisiopatología , Femenino , Escala de Coma de Glasgow , Humanos , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Curva ROC , Accidente Cerebrovascular/fisiopatología
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