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BACKGROUND: Asthma can manifest in a variety of clinical phenotypes like cough variant asthma, chest tightness variant asthma (CTVA), and masked asthma. Patients with CTVA usually have a singular or primary complaint of chest tightness, which is often overlooked or misdiagnosed due to the lack of characteristic asthma symptoms. We hereby report a case of CTVA managed by omalizumab. CASE REPORT: A 15-year-old female patient reported to us with repeated coughing persisting for 3 weeks. Initial treatment with standard asthma drugs had minimal effect. Later during the disease, chest tightness became the primary symptom, and she was managed with steroids, ß2 receptor agonists, and leukotriene receptor agonists but without complete relief. Based on clinical signs and symptoms, the response to baseline drugs, and results of bronchial provocation test, the diagnosis was revised to CTVA, and the patient was started on Omalizumab in addition to baseline drugs, which significantly improved her condition. CONCLUSIONS: CTVA is difficult to diagnose due to its insidious symptoms and poor characteristics. Improper treatment can lead to uncontrolled disease, negative psychological issues, and reduced quality of life. Comprehensive assessment of children's airway inflammation level, lung function, bronchial provocation test, and responsiveness to drug therapy should be performed for accurate diagnosis. Omalizumab in combination with standard drugs can significantly improve the outcomes of CTVA. [ABSTRACT FROM AUTHOR]

It has been decade-long and enduring efforts to decipher the structural mechanism of plasticity in metallic glasses; however, it still remains a challenge to directly reveal the structural change, if any, that precedes; and dominant plastics flow in them. Here, by using the dynamic atomic force microscope as an "imaging" as well as a "forcing" tool, we unfold a real-time sequence of structural evolution occurring on the surface of an Au-Si thin film metallic glass. In sharp contrast to the common notion that plasticity comes along with mechanical softening in bulk metallic glasses, our experimental results directly reveal three types of nano-sized surface regions, which undergo plasticity but exhibit different characters of structural evolution following the local plasticity events, including stochastic structural rearrangement, unusual local relaxation and rejuvenation. As such, yielding on the metallic-glass surface manifests as a dynamic equilibrium between local relaxation and rejuvenation as opposed to shear instability in bulk metallic-glasses. Our finding demonstrates that plasticity on the metallic glass surface of Au-Si metallic glass bears much resemblance to that of the colloidal gels, of which nonlinear rheology rather than shear instability governs the constitutive behavior of plasticity. [ABSTRACT FROM AUTHOR]

High-performance ultraviolet (UV) detectors with both high responses and fast speeds are hard to make on homogeneous crystal semiconductor materials. Here, the UV response characteristics of mixed-phase MgZnO thin films with different internal structure distributions are studied. The mixed-phase MgZnO-based detector with the given crystal composition has a high response at both deep UV light (96 A W−1 at 240 nm) and near UV light (80 A W−1 at 335 nm). Meanwhile, because of the quasi-tunneling breakdown mechanism within the device, the high-response UV detector also shows a fast response speed (tr = 0.11 μs) and recovery speed (td1 = 26 μs) at deep UV light, which is much faster than both low-response mixed-phase MgZnO-based UV detectors with other structure constitutions and reported high-response UV devices on homogenous crystal materials. The Idark of the device is just 4.27 pA under a 5 V bias voltage, so the signal-to-noise ratio of the device reached 23852 at 5.5 uW cm−2 235 nm UV light. The new quasi-tunneling breakdown mechanism is observed in some mixed-phase MgZnO thin films that contain both c-MgZnO and h-MgZnO parts, which introduce a high response, signal-to-noise ratio, and fast speed into mixed-phase MgZnO-based UV detectors at weak deep UV light. [ABSTRACT FROM AUTHOR]

YBa2Cu3O7-δ (YBCO) thin films with various thicknesses from 80 nm to 2000 nm are prepared on single crystal SrTiO3 by means of pulsed laser deposition technique. While it is hard for the x-ray diffraction to observe the evolutions in epitaxial orientation and interior lattice structure, the atomic force microscope shows the degraded surface morphologies and coalesced particles which arise from more misoriented grains with increasing thin film thickness. A detailed Raman spectrum investigation reveals that the a-axis grains exist predominately at the top surface of the films as the total thickness of the film increases up to 2000 nm. It is also evident that the Raman peak corresponding to the O2+/O3- mode emerges with the redshift first and then the blueshift as the film thickness increases. These Raman shifts suggest that the tensile stress in the (a, b) plane arising from the lattice mismatch between the epitaxial film and substrate may release gradually with increasing the film thickness, while the additional tensile stress emerges due to the a-axis grains present at the top surface of thin film. It is believed that the thickness effect of YBCO thin films on the superconducting transition temperature (Tc) and critical current density (Jc) is attributed to the variation of interior residual stress and surface morphology associated with the lattice mismatch and grain orientation, respectively. [ABSTRACT FROM AUTHOR]

Resistive switching is frequently associated with local heating of the switching structure. The mechanical effect of such heating on Pt/SrTiO3 (001) Schottky barriers and on Pt/SrZrO3/SrRuO3/SrTiO3 switching devices was examined. The extent and magnitude of Joule heating was assessed using IR microscopy at power dissipation levels similar to what others have reported during electroforming. Lines aligned along the [100] and [010] directions were observed spreading laterally around the locally heated area imaged by IR. Atomic force microscopy, transmission electron microscopy. and electron channeling contrast imaging suggest these lines are slip lines due to the plastic deformation induced by the local compressive stresses created by Joule heating. The deformation pattern is identical to that produced by nanoindentation. The implications of deformation for resistive switching systems are discussed. [ABSTRACT FROM AUTHOR]

Capacitance-voltage characteristics of high quality Pt Schottky diodes fabricated on oxygen-vacancy-doped SrTiO3 single crystals were used to obtain the oxygen vacancy profiles within one microns of the Pt interface. Computer simulations based on solving the drift-diffusion equations for electrons and ionized vacancies were performed to understand the experimentally observed oxygen vacancy profile's time-evolution at room temperature and 0 V applied bias. Building upon this understanding, the diode's room temperature profile evolution under -35 V applied bias was analyzed to yield a vacancy mobility value of 1.5 × 10-13 cm2/V·s at an electric field of 500 kV/cm. This mobility is 8 orders of magnitude too low to produce nanosecond resistance switching in thin film devices. The applicability of the results to oxygen-migration-based resistance switching is discussed relative to recent observations and modeling. [ABSTRACT FROM AUTHOR]