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1.
Children (Basel) ; 9(1)2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-35053688

RESUMO

BACKGROUND: This study analyzed the presentation, characteristics, and management of foreign bodies in different age groups of pediatric patients with ear, nose, and throat foreign bodies. METHODS: A retrospective study was performed using data from October 2012 to September 2020. A total of 1285 patients with ear, nose, and throat foreign bodies who were less than 12 years of age and who presented to the emergency room were included in this study. Their biographical data, clinical presentations, foreign body types and locations, and management outcomes were obtained from medical records and analyzed as three age groups (infancy: <2 years old; early childhood: 2-5 years old; and late childhood: 6-12 years old). RESULTS: The early childhood group had the highest number of patients (n = 672; 52.2%). Throat was the most common location (59.2%), and bone was the most common type of foreign body. Among the children who visited our hospital, foreign bodies were actually found in only 657 patients (51.1%) and removed by an otolaryngologist in 625 (95.1%) cases. CONCLUSION: Our study could provide guidance for the diagnosis and management of pediatric patients who present to emergency departments with foreign bodies.

2.
ACS Nano ; 15(10): 16395-16403, 2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34608798

RESUMO

Interface engineering is an effective approach to tune the magnetic properties of van der Waals (vdW) magnets and their heterostructures. The prerequisites for the practical utilization of vdW magnets and heterostructures are a quantitative analysis of their magnetic anisotropy and the ability to modulate their interfacial properties, which have been challenging to achieve with conventional methods. Here we characterize the magnetic anisotropy of Fe3GeTe2 layers by employing the magnetometric technique based on anomalous Hall measurements and confirm its intrinsic nature. In addition, on the basis of the thickness dependences of the anisotropy field, we identify the interfacial and bulk contributions. Furthermore, we demonstrate that the interfacial anisotropy in Fe3GeTe2-based heterostructures is locally controlled by adjacent layers, leading to the realization of multiple magnetic behaviors in a single channel. This work proposes that the magnetometric technique is a useful platform for investigating the intrinsic properties of vdW magnets and that functional devices can be realized by local interface engineering.

3.
Artigo em Inglês | MEDLINE | ID: mdl-34574801

RESUMO

The sinonasal microbiota in human upper airway may play an important role in chronic rhinosinusitis (CRS). Thus, this study aimed to investigate the human upper airway microbiome in patients with unilateral CRS, and compare the sinonasal microbiome of the unilateral diseased site with that of a contralateral healthy site. Thirty samples, 15 each from the diseased and healthy sites, were collected from the middle meatus and/or anterior ethmoid region of 15 patients with unilateral CRS during endoscopic sinus surgery. DNA extraction and bacterial microbiome analysis via 16S rRNA gene sequencing were then performed. Corynebacterium showed the highest relative abundance, followed by Staphylococcus in samples from both the diseased and healthy sites. Further, the relative abundances of Staphylococcus and Pseudomonas were significantly lower in samples from diseased sites than in those from healthy sites. Conversely, anaerobes, including Fusobacterium, Bacteroides, and Propionibacterium, were abundantly present in samples from both sites, more so in samples from diseased sites. However, the sites showed no significant difference with respect to richness or diversity (p > 0.05). Our results indicate that CRS might be a polymicrobial infection, and also suggest that Corynebacterium and Staphylococcus may exist as commensals on the sinus mucosal surface in the upper respiratory tract.


Assuntos
Microbiota , Seios Paranasais , Rinite , Sinusite , Doença Crônica , Humanos , RNA Ribossômico 16S/genética
4.
Medicina (Kaunas) ; 57(8)2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34440949

RESUMO

Background and Objectives: Tinnitus is a condition that negatively affects the quality of life and is difficult to treat. Theta burst stimulation (TBS), a new method of repetitive transcranial magnetic stimulation (rTMS), is a promising treatment approach because it shows stronger and more prolonged effects in a shorter time of stimulation than other rTMS protocols. However, the therapeutic effect of TBS for tinnitus was inconsistent. We hypothesized that more stimulation would be more effective. Therefore, this study aimed to explore the safety and effectiveness of multiple daily rounds of TBS over five consecutive days. Materials and Methods: The continuous TBS (cTBS) protocol is 300 pulses/day, but we applied 8 sessions of 300 pulses in a day (total 2400 pulses/day). A total of 15 patients with tinnitus were randomly assigned to treatment and sham groups. Outcome measurements were taken three times: before and after 5-day of stimulation; at a 1-3 month follow-up visit. Outcome measurements were the degree of annoyance due to ear fullness, duration of tinnitus, visual analog scales of tinnitus for annoyance, Tinnitus Handicap Inventory, pitch, loudness, minimum masking level, and residual inhibition. Results: Five-day cTBS was completed without adverse events. We did not find any significant therapeutic effect in the treatment group, but we needed to be cautious to interpret our result due to the small sample size. Conclusions: In conclusion, multiple rounds of cTBS in a day may be safe. Further research is needed in a larger sample size to determine the effectiveness and confirm the safety.


Assuntos
Zumbido , Humanos , Medição da Dor , Qualidade de Vida , Projetos de Pesquisa , Zumbido/terapia , Estimulação Magnética Transcraniana , Resultado do Tratamento
5.
Nat Commun ; 10(1): 4510, 2019 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-31586096

RESUMO

A polar conductor, where inversion symmetry is broken, may exhibit directional propagation of itinerant electrons, i.e., the rightward and leftward currents differ from each other, when time-reversal symmetry is also broken. This potential rectification effect was shown to be very weak due to the fact that the kinetic energy is much higher than the energies associated with symmetry breaking, producing weak perturbations. Here we demonstrate the appearance of giant nonreciprocal charge transport in the conductive oxide interface, LaAlO3/SrTiO3, where the electrons are confined to two-dimensions with low Fermi energy. In addition, the Rashba spin-orbit interaction correlated with the sub-band hierarchy of this system enables a strongly tunable nonreciprocal response by applying a gate voltage. The observed behavior of directional response in LaAlO3/SrTiO3 is associated with comparable energy scales among kinetic energy, spin-orbit interaction, and magnetic field, which inspires a promising route to enhance nonreciprocal response and its functionalities in spin orbitronics.

6.
J Phys Chem Lett ; 10(11): 2745-2752, 2019 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-31082242

RESUMO

Quantum confinement-driven band structure engineering of metal halide perovskites (MHPs) is examined for realistically sized structures that consist of up to 105 atoms. The structural and compositional effects on band gap energies are simulated for crystalline CH3NH3PbX3 (X = I/Br/Cl) with a tight-binding approach that has been well-established for electronic structure calculations of multimillion atomic systems. Solid maps of band gap energies achievable with quantum dots, nanowires, and nanoplatelets concerning sizes, shapes, and halide compositions are presented, which should be informative to experimentalists for band gap designs. The pathway to suppress band gap instability that appeared in mixed halide perovskites is proposed, revealing that the red shift induced by halide phase separation can be hugely diminished by reducing sizes and adopting halides of lower electronegativity. Our modeling results on finite MHP structures of over 10 nm dimensions show a blueprint for designs of stable light-emitting sources with precisely controlled wavelengths.

8.
Sensors (Basel) ; 18(9)2018 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-30149639

RESUMO

In this paper, we propose a new method for the generation of microimages, which processes real 3D scenes captured with any method that permits the extraction of its depth information. The depth map of the scene, together with its color information, is used to create a point cloud. A set of elemental images of this point cloud is captured synthetically and from it the microimages are computed. The main feature of this method is that the reference plane of displayed images can be set at will, while the empty pixels are avoided. Another advantage of the method is that the center point of displayed images and also their scale and field of view can be set. To show the final results, a 3D InI display prototype is implemented through a tablet and a microlens array. We demonstrate that this new technique overcomes the drawbacks of previous similar ones and provides more flexibility setting the characteristics of the final image.

9.
Sci Rep ; 8(1): 3397, 2018 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-29467374

RESUMO

In a strong spin-orbit interaction system, the existence of three resistance states were observed when two ferromagnetic (FM) contacts were used as current terminals while a separate normal metal contact pair was used as voltage terminals. This result is strikingly different from ordinary spin valve or magnetic tunnel junction devices, which have only two resistance states corresponding to parallel (RP) and antiparallel (RAP) alignments of the FM contacts. Our experimental results on a quantum well layer with a strong Rashba effect clearly exhibit unequal antiparallel states, i.e., RAP(1) > RP > RAP(2), up to room temperature. The three-states are observed without any degradation when the distance between the non-magnetic voltage probe and the ferromagnetic current probe was increased up to 1.6 mm.

10.
ACS Appl Mater Interfaces ; 9(22): 18790-18798, 2017 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-28537377

RESUMO

Fluorocarbon (CxFy) anode materials were developed for lithium- and sodium-ion batteries through a facile one-step carbonization of a single precursor, polyvinylidene fluoride (PVDF). Interconnected carbon network structures were produced with doped fluorine in high-temperature carbonization at 500-800 °C. The fluorocarbon anodes derived from the PVDF precursor showed higher reversible discharge capacities of 735 mAh g-1 and 269 mAh g-1 in lithium- and sodium-ion batteries, respectively, compared to the commercial graphitic carbon. After 100 charge/discharge cycles, the fluorocarbon showed retentions of 91.3% and 97.5% in lithium (at 1C) and sodium (at 200 mA g-1) intercalation systems, respectively. The effects of carbonization temperature on the electrochemical properties of alkali metal ion storage were thoroughly investigated and documented. The specific capacities in lithium- and sodium-ion batteries were dependent on the fluorine content, indicating that the highly electronegative fluorine facilitates the insertion/extraction of lithium and sodium ions in rechargeable batteries.

11.
Sci Adv ; 3(4): e1602531, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28439549

RESUMO

Topological insulators (TIs), with their helically spin-momentum-locked topological surface states (TSSs), are considered promising for spintronics applications. Several recent experiments in TIs have demonstrated a current-induced electronic spin polarization that may be used for all-electrical spin generation and injection. We report spin potentiometric measurements in TIs that have revealed a long-lived persistent electron spin polarization even at zero current. Unaffected by a small bias current and persisting for several days at low temperature, the spin polarization can be induced and reversed by a large "writing" current applied for an extended time. Although the exact mechanism responsible for the observed long-lived persistent spin polarization remains to be better understood, we speculate on possible roles played by nuclear spins hyperfine-coupled to TSS electrons and dynamically polarized by the spin-helical writing current. Such an electrically controlled persistent spin polarization with unprecedented long lifetime could enable a rechargeable spin battery and rewritable spin memory for potential applications in spintronics and quantum information.

12.
Sci Rep ; 6: 35658, 2016 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-27767047

RESUMO

It is experimentally established that charge current flowing in a channel with spin-momentum locking such as topological insulator surface states or Rashba interfaces induces a spin voltage, which can be electrically measured with a ferromagnetic contact along the current path. Using this fact in conjunction with Onsager reciprocity arguments, we make the surprising prediction that the anti-parallel resistance of a spin valve can be either larger or smaller than the parallel resistance depending on the direction of spin flow relative to the direction of spin-momentum locking. However, we argue that this remarkable signature of spin-momentum locking can only be observed in multi-terminal measurements. Two-terminal measurements in the linear response regime, will show a single anti-parallel resistance larger than the parallel resistance as commonly observed in channels without spin-orbit coupling. We support this result with detailed numerical calculations based on a semiclassical model that provides insight into the underlying physics.

13.
Sci Rep ; 6: 34590, 2016 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-27698448

RESUMO

Microporous carbon compartments (MCCs) were developed via controlled carbonization of wheat flour producing large cavities that allow CO2 gas molecules to access micropores and adsorb effectively. KOH activation of MCCs was conducted at 700 °C with varying mass ratios of KOH/C ranging from 1 to 5, and the effects of activation conditions on the prepared carbon materials in terms of the characteristics and behavior of CO2 adsorption were investigated. Textural properties, such as specific surface area and total pore volume, linearly increased with the KOH/C ratio, attributed to the development of pores and enlargement of pores within carbon. The highest CO2 adsorption capacities of 5.70 mol kg-1 at 0 °C and 3.48 mol kg-1 at 25 °C were obtained for MCC activated with a KOH/C ratio of 3 (MCC-K3). In addition, CO2 adsorption uptake was significantly dependent on the volume of narrow micropores with a pore size of less than 0.8 nm rather than the volume of larger pores or surface area. MCC-K3 also exhibited excellent cyclic stability, facile regeneration, and rapid adsorption kinetics. As compared to the pseudo-first-order model, the pseudo-second-order kinetic model described the experimental adsorption data methodically.

14.
Sci Rep ; 6: 20325, 2016 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-26932563

RESUMO

In this paper we present a general theory for an arbitrary 2D channel with "spin momentum locking" due to spin-orbit coupling. It is based on a semiclassical model that classifies all the channel electronic states into four groups based on the sign of the z-component of the spin (up (U), down (D)) and the sign of the x-component of the velocity (+, -). This could be viewed as an extension of the standard spin diffusion model which uses two separate electrochemical potentials for U and D states. Our model uses four: U+, D+, U-, and D-. We use this formulation to develop an equivalent spin circuit that is also benchmarked against a full non-equilibrium Green's function (NEGF) model. The circuit representation can be used to interpret experiments and estimate important quantities of interest like the charge to spin conversion ratio or the maximum spin current that can be extracted. The model should be applicable to topological insulator surface states with parallel channels as well as to other layered structures with interfacial spin-orbit coupling.

15.
Sci Rep ; 5: 14293, 2015 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-26391089

RESUMO

Topological insulators (TIs) are an unusual phase of quantum matter with nontrivial spin-momentum-locked topological surface states (TSS). The electrical detection of spin-momentum-locking of TSS has been lacking till very recently. Many of the results are from samples with significant bulk conduction, such as Bi2Se3, where it can be challenging to separate the surface and bulk contribution to the spin signal. Here, we report spin potentiometric measurements in flakes exfoliated from bulk insulating Bi2Te2Se crystals, using two outside nonmagnetic contacts for driving a DC spin helical current and a middle ferromagnetic (FM)-Al2O3 contact for detecting spin polarization. The voltage measured by the FM electrode exhibits a hysteretic step-like change when sweeping an in-plane magnetic field between opposite directions along the easy axis of the FM contact. Importantly, the direction of the voltage change can be reversed by reversing the direction of current, and the amplitude of the change as measured by the difference in the detector voltage between opposite FM magnetization increases linearly with increasing current, consistent with the current-induced spin polarization of spin-momentum-locked TSS. Our work directly demonstrates the electrical injection and detection of spin polarization in TI and may enable utilization of TSS for applications in nanoelectronics and spintronics.

16.
J Nanosci Nanotechnol ; 11(1): 432-6, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21446470

RESUMO

Reported herein are the effects of the fabrication variables and surface capping of nanocrystal quantum dots (NQDs) on the characteristics of NQDs-based light-emitting diodes (LEDs). The molecular weight of the hole transport layer (HTL) material and the annealing conditions of the NQDs layer were chosen as fabrication process variables. Their effects on the layer characteristics and device efficiency were characterized. The maximum brightness varied over 50% according to the molecular weight of the HTL material. The optimized annealing temperature was shown to improve the maximum brightness by 20%. The surface-capping molecules of the NQDs were changed from conventional trioctyl phosphine/trioctyl phosphine oxide (TOPO/TOP) to pyridine and were incorporated into LEDs, and its effects on the device characteristics were discussed.

17.
Am J Physiol Renal Physiol ; 296(1): F25-33, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18971208

RESUMO

In postischemic acute kidney injury (AKI) or acute renal failure, a dissipation of glomerular filtration pressure is associated with an altered renal vascular tone and reactivity, as well as a loss of vascular autoregulation. To test the hypothesis that renal nitric oxide (NO) generation reflects endothelial damage in the kidney after ischemia-reperfusion, we quantified the urinary NO levels and identified the site of its generation in postischemic AKI. Subjects were 50 recipients of cadaveric renal allografts: 15 with sustained AKI and 35 with recovering renal function. Urine and blood samples were obtained after transplant, and intraoperative allograft biopsies were performed to examine NO synthases (NOSs) in the kidney. In the sustained AKI group, urinary nitrite and nitrate excretion (in mumol/g urine creatinine) was lower (12.3 +/- 1.8 and 10.0 +/- 1.4 on postoperative days 0 and 3) than in the recovery group [20.0 +/- 3.6 and 35.1 +/- 5.3 (P < 0.005 vs. sustained AKI on days 0 and 3) on postoperative days 0 and 3]. Endothelial NOS expression diminished from the peritubular capillaries of 6 of 7 subjects in the sustained AKI group but from only 6 of 16 subjects in the recovery group. No differences were observed in the inducible NOS staining pattern between the two groups. Neuronal NOS staining was rarely observed in the macula densae of subjects but was prominent in control tissues. These findings suggest that a diminished NO generation by injured endothelium and loss of macula densa neuronal NOS could impair the vasodilatory ability of the renal vasculature and contribute to the reduction in the glomerular filtration rate in postischemic AKI.


Assuntos
Injúria Renal Aguda/metabolismo , Endotélio Vascular/metabolismo , Túbulos Renais Distais/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Óxido Nítrico/metabolismo , Traumatismo por Reperfusão/metabolismo , Injúria Renal Aguda/patologia , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Criança , Endotélio Vascular/patologia , Feminino , Humanos , Transplante de Rim/patologia , Túbulos Renais Distais/irrigação sanguínea , Túbulos Renais Distais/patologia , Masculino , Pessoa de Meia-Idade , Óxido Nítrico Sintase Tipo II/metabolismo , Traumatismo por Reperfusão/patologia , Transplante Homólogo , Adulto Jovem
18.
Am J Physiol Renal Physiol ; 295(2): F351-9, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18562634

RESUMO

Decreased renal blood flow following an ischemic insult contributes to a reduction in glomerular filtration. However, little is known about the underlying cellular or subcellular mechanisms mediating reduced renal blood flow in human ischemic acute kidney injury (AKI) or acute renal failure (ARF). To examine renal vascular injury following ischemia, intraoperative graft biopsies were performed after reperfusion in 21 cadaveric renal allografts. Confocal fluorescence microscopy was utilized to examine vascular smooth muscle and endothelial cell integrity as well as peritubular interstitial pericytes in the biopsies. The reperfused, transplanted kidneys exhibited postischemic injury to the renal vasculature, as demonstrated by disorganization/disarray of the actin cytoskeleton in vascular smooth muscle cells and disappearance of von Willebrand factor from vascular endothelial cells. Damage to peritubular capillary endothelial cells was more severe in subjects destined to have sustained ARF than in those with rapid recovery of their graft function. In addition, peritubular pericytes/myofibroblasts were more pronounced in recipients destined to recover than those with sustained ARF. Taken together, these data suggest damage to the renal vasculature occurs after ischemia-reperfusion in human kidneys. Preservation of peritubular capillary endothelial integrity and increasing pericytes may be critical to recovery from postischemic AKI.


Assuntos
Endotélio Vascular/patologia , Nefropatias/patologia , Túbulos Renais/irrigação sanguínea , Túbulos Renais/patologia , Pericitos/patologia , Recuperação de Função Fisiológica/fisiologia , Traumatismo por Reperfusão/patologia , Actinas/metabolismo , Doença Aguda , Injúria Renal Aguda/patologia , Injúria Renal Aguda/fisiopatologia , Biópsia , Endotélio Vascular/citologia , Feminino , Humanos , Nefropatias/fisiopatologia , Transplante de Rim/patologia , Transplante de Rim/fisiologia , Túbulos Renais/citologia , Masculino , Microscopia Confocal , Pessoa de Meia-Idade , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Traumatismo por Reperfusão/fisiopatologia
19.
J Histochem Cytochem ; 55(6): 575-84, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17312013

RESUMO

We have previously shown that postischemic injury to renal allografts results in profound impairment of p-aminohippuric acid (PAH) extraction. To elucidate the cellular integrity of the human organic anion transporter 1 (hOAT1) in postischemic acute renal failure (ARF), immunohistochemical analysis of hOAT1 was performed in cadaveric renal allografts using confocal microscopy for three-dimensional reconstruction of serial optical images. Biopsy samples were obtained from 10 cadaveric renal allografts 1 hr after reperfusion during transplant operation. Control tissues were obtained from four living donors of healthy kidneys immediately before an arterial clamp was applied to the renal artery. Control tissues demonstrated hOAT1 distributed to basolateral membrane of proximal tubule cells. In contrast, maldistribution of hOAT1 to cytoplasm and/or diminution of the protein was noted in cadaveric allografts. Characteristics of maldistribution were variable: disappearance of lateral distribution, diffuse cytoplasmic aggregates, apical cytoplasmic aggregates, and disappearance of the staining. In addition, iothalamate and PAH clearances were performed on posttransplant days 3-7 in 18 recipients of a cadaveric renal allograft. PAH clearance was depressed <250 ml/min in all but three subjects. We conclude that reperfused, transplanted kidneys exhibit maldistribution of hOAT1 in proximal tubule cells, resulting in impairment of PAH clearance. This manuscript contains online supplemental material at http://www.jhc.org. Please visit this article online to view these materials.


Assuntos
Transplante de Rim/métodos , Rim/metabolismo , Proteína 1 Transportadora de Ânions Orgânicos/análise , Adulto , Cadáver , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Imuno-Histoquímica , Ácido Iotalâmico/farmacocinética , Isquemia/fisiopatologia , Rim/fisiopatologia , Rim/cirurgia , Túbulos Renais Proximais/metabolismo , Doadores Vivos , Masculino , Taxa de Depuração Metabólica , Microscopia de Fluorescência , Pessoa de Meia-Idade , Reperfusão , Doadores de Tecidos , Transplante Homólogo , Ácido p-Aminoipúrico/farmacocinética
20.
Curr Opin Mol Ther ; 6(6): 608-15, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15663325

RESUMO

Two-dimensional electrophoresis (2-DE) remains an important technology in the study of protein expression. In many applications, 2-DE has been supplanted by liquid chromatographic and mass spectrometric approaches that overcome some of its limitations and labor intensiveness. Nevertheless, 2-DE has exceptional relevance in toxicology and, despite the challenges, its implementation continues to support toxicologists in understanding the biological effects of chemical exposures in living systems. This review will address the use of 2-DE-based proteomics in toxicology and recent developments in this strategy, considering the unique nature of toxicity testing and the issues of dynamic range and reproducibility that have previously limited the overall utility of 2-DE in this field.


Assuntos
Eletroforese em Gel Bidimensional/métodos , Eletroforese em Gel Bidimensional/tendências , Géis , Toxicogenética/métodos , Animais , Humanos , Proteômica/métodos , Proteômica/tendências
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