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Byline: Jae-Hwan Kim, Jung-Yup Kim, Seung-Bok Choi, Kyung-Su Kim This paper demonstrates the possibility of the shock wave reduction of ER insert in structures. ER (electrorheological) fluid is a smart material of which stiffness and damping properties can be controlled by applying electric field. When an ER fluid is inserted into a structure and an appropriate magnitude of electric field is applied, propagating waves can be selectively isolated. To experimentally verify the shock wave reduction, an ER insert is made in an aluminum plate and two piezoceramic disks are used as transmitter and receiver for the wave transmission test. By applying an electric field to the ER insert, the transmitted wave is reduced. This measured wave reduction is compared with the predictions of transient finite element analysis. Since the use of ER inserts has merits in terms of light weight and controllability, this technology can be used for many applications, for example, dash panels for vehicles, interior trim panels for aircraft, impact resistance system for civil and warship structures.

Objective: Fungal rhinosinusitis occurs in different forms depending on race and region. While allergic fungal rhinosinusitis is common in Caucasians, fungal ball (FB) is more common in Asians. However, most cases are reported as unilateral, and clinical data on bilateral FB (BFB) are rare. Therefore, the purpose of this study was to analyze and to compare the clinical characteristics of BFB and unilateral FB (UFB) in Koreans. Methods: We retrospectively analyzed medical records and computed tomography (CT) images of 434 patients diagnosed with FB. The patients were divided into two groups: BFB and UFB. Demographic data, multiple allergen simultaneous test including total or specific immunoglobulin E (IgE) levels, symptoms, CT findings, treatment, and outcomes were analyzed. Results: Among the patients, 26 had BFB and 408 had UFB. Hypertension was noted in 61.5% of the BFB and 39% of the UBF individuals (p = 0.023). While total IgE levels were similar between the two groups, Dermatophagoides pteronyssinus (p = 0.004), Cladosporium (p = 0.017), and Aspergillus-specific IgE positivity (p = 0.025) were significantly higher in the BFB than in the UFB group. Not only symptoms such as postnasal drip (p = 0.013), mucopurulent rhinorrhea (p = 0.009), and foul odor (p = 0.037), but also sphenoid sinus involvement on CT images were more common in the BFB than in the UFB group (p = 0.011). Conclusion: Patients with BFB in Korea showed more common hypertension and symptoms of foul odor, mucopurulent rhinorrhea, and postnasal drip with allergy positivity compared to those with UFB. Therefore, understanding clinical characteristics of BFB will allow clinicians to approach BFB more appropriately. [ABSTRACT FROM AUTHOR]

A unique three-dimensional hybrid NiCo(CO 3)(OH) 2 nanowire/NiMn(CO 3)(OH) 2 nanosheet composite was fabricated using a facile hydrothermal method as a binder-free electrode directly grown on Ni foam for supercapacitors. We examined the synergistic effect by fabricating Ni-Co-Mn ternary electrodes that used Ni-Co with a large specific surface area and Mn with a very high theoretical capacity. The new hybrid electrode had good electrochemical characteristics, exhibiting remarkably high specific capacitances of 1673.3 and 453.0 F g−1 at 3 and 15 A g−1, respectively. Compared with other samples, the capacitance showed less reduction as the current density increased. This result indicates stable electrode properties with increasing voltage. The cycling stability of the hybrid NiCo(CO 3)(OH) 2 /NiMn(CO 3)(OH) 2 composite was measured as 82.1% after 5000 cycles. Additionally, we fabricated an asymmetric supercapacitor employing the NiCo(CO 3)(OH) 2 /NiMn(CO 3)(OH) 2 composite as the positive electrode and graphene as the negative electrode, which exhibited a high energy density of 27.2 W h kg−1 at a power density of 702.7 W kg−1 and a remarkable cycling stability, with 89.4% capacitance retention after 5000 cycles. Thus, for the first time, we investigated the dual nano-type structure of an NiCo(CO 3)(OH) 2 nanowire/NiMn(CO 3)(OH) 2 nanosheet electrode for supercapacitors and obtained satisfactory results. • The NiCo(CO 3)(OH) 2 nanowire-NiMn(CO 3)(OH) 2 nanosheet composite was fabricated. • The NiCo(CO 3)(OH) 2 -NiMn(CO 3)(OH) 2 composite has high electrochemical properties. • The NiCo(CO 3)(OH) 2 -NiMn(CO 3)(OH) 2 composite made via a hydrothermal method. • The supercapacitor fabricated using this composite can turn on the LED light. [ABSTRACT FROM AUTHOR]

Abstract In the joint sparse recovery, where the objective is to recover a signal matrix X 0 of size n × l or a set Ω of its nonzero row indices from incomplete measurements, subspace-based greedy algorithms improving MUSIC such as subspace-augmented MUSIC and sequential compressive MUSIC have been proposed to improve the reconstruction performance of X 0 and Ω with a computational efficiency even when rank (X 0) ≤ k ≔ | Ω |. However, the main limitation of the MUSIC-like methods is that they most likely fail to recover the signal when a partial support estimate of k − rank (X 0) indices for their input is not fully correct. We proposed a computationally efficient algorithm called two-stage iterative method to detect the remained support (T-IDRS), its special version termed by two-stage orthogonal subspace matching pursuit (TSMP), and its variant called TSMP with sparse Bayesian learning (TSML) by exploiting more than the sparsity k to estimate the signal matrix. They improve on the MUSIC-like methods such that these are guaranteed to recover the signal and its support while the existing MUSIC-like methods will fail in the practically significant case of MMV when rank (X 0) ∕ k is sufficiently small. Numerical simulations demonstrate that the proposed schemes have low complexities and most likely outperform other related methods. A condition of the minimum m required for TSMP to recover the signal matrix is derived in the noiseless case to be applicable to a wide class of the sensing matrix. [ABSTRACT FROM AUTHOR]

Background: Although a significant number of the clinical features and pathophysiologic mechanisms of chronic rhinosinusitis (CRS) have been described, only a few studies have been published on characterization of CRS in the field of aging. Objective: We investigated the prevalence and risk factors of CRS in elderly (≥65 years old) Koreans using large-scale nationwide epidemiological data and compared the risk factors of elderly with those of younger adult participants (19–64 years old). Methods: Data from 25 529 participants who completed the 2008–2012 Korean National Health and Nutrition Examination Survey were analyzed. Diagnosis of CRS was done according to the EP3OS 2012 guideline for epidemiologic study. Risk factors of CRS were compared in the aspects of sociodemographics, general health behaviors, clinical characteristics, and comorbidities of participants. Results: The prevalence of CRS was significantly higher in 5590 elderly than in 19 939 younger adults (6.55% vs 5.69%; P =.016. Some variables of socioeconomic status and mental health in the adult group were associated with increased risk of CRS but did not show association in the elderly group. We observed a significant association between CRS prevalence and comorbid allergic rhinitis, asthma, and atopic dermatitis in both groups (P <.05). However, in the elderly group, the associations were significantly weaker with regard to allergic rhinitis (P -interaction =.03) and asthma (P -interaction =.002). Conclusion: These results suggest that elderly populations have distinct pathophysiology and clinical presentations from adult CRS, and management for elderly patients with CRS may require different or additional therapeutic approaches. [ABSTRACT FROM AUTHOR]

It is widely held that disorder is essential to the existence of a finite interval of magnetic field in which the Hall conductance is quantized, i.e., for the existence of "plateaus" in the quantum Hall effect. Here, we show that the existence of a quasi-particle Wigner crystal (QPWC) results in the persistence of plateaus of finite extent even in the limit of vanishing disorder. Several experimentally detectable features that characterize the behavior in the zero disorder limit are also explored. [ABSTRACT FROM AUTHOR]