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In this work, the effects of noble metal (Au and Pt) incorporation into black phosphorus (BP) were first investigated. Several important sensing results were observed as a result of the incorporation of Au or Pt into the BP surface. First, prior to incorporation, pristine BP only detects paramagnetic molecules, e.g., NO2 or NO. However, after incorporation with Pt, low concentration of H2 can be detected with high response amplitude. Furthermore, the H2 sensing performance reported in this study was found to be most sensitive as compared with that observed for a previously reported 2D H2 gas sensor. The second significant result was obtained after incorporation with Au, where the work function of BP was varied by the transfer of electrons from the Au nanoparticles, thereby inducing the effects of n-doping on p-type pristine BP. Accordingly, the response behavior of BP to oxidizing gas changed from a p-type response (negative resistance variation) to an n-type response (positive resistance variation). In addition, a highly stable, low noise baseline was achieved in the Au-incorporated BP channel material. Finally, because of the high chemical and ambient stability of the Au or Pt, the synthesized Au- or Pt-incorporated BP systems exhibited long-term stability, which is difficult to achieve when using other doping strategies. Overall, a significant step was taken toward the efficient control of the electrical/chemical sensitization level of BP and significant enhancement of superior chemical sensing performance of BP. [ABSTRACT FROM AUTHOR]

The development of high-performance volatile organic compound (VOC) sensor based on a p-type metal oxide semiconductor (MOS) is one of the important topics in gas sensor research because of its unique sensing characteristics, namely, rapid recovery kinetics, low temperature dependence, high humidity or thermal stability, and high potential for p-n junction applications. Despite intensive efforts made in this area, the applications of such sensors are hindered because of drawbacks related to the low sensitivity and slow response or long recovery time of p-type MOSs. In this study, the VOC sensing performance of a p-type MOS was significantly enhanced by forming a patterned p-type polycrystalline MOS with an ultrathin, high-aspect-ratio (∼25) structure (∼14 nm thickness) composed of ultrasmall grains (∼5 nm size). A high-resolution polycrystalline p-type MOS nanowire array with a grain size of ∼5 nm was fabricated by secondary sputtering via Ar+ bombardment. Various p-type nanowire arrays of CuO, NiO, and Cr2O3 were easily fabricated by simply changing the sputtering material. The VOC sensor thus fabricated exhibited higher sensitivity (ΔR/Ra = 30 at 1 ppm hexane using NiO channels), as well as faster response or shorter recovery time (∼30 s) than that of previously reported p-type MOS sensors. This result is attributed to the high resolution and small grain size of p-type MOSs, which lead to overlap of fully charged zones; as a result, electrical properties are predominantly determined by surface states. Our new approach may be used as a route for producing high-resolution MOSs with particle sizes of ∼5 nm within a highly ordered, tall nanowire array structure. [ABSTRACT FROM AUTHOR]

Enhancement of the fluorescence intensityof quantum dot (QD)–polymer nanocomposite arrays is an importantissue in QD studies because of the significant reduction of fluorescencesignals of such arrays due to nonradiative processes in densely packedpolymer chains in solid films. In this study, we enhance the fluorescenceintensity of such arrays without significantly reducing their opticaltransparency. Enhanced fluorescence is achieved by hybridizing ultrathinplasmonic Au nanowalls onto the sidewalls of the arrays via single-steppatterning and hybridization. The plasmonic Au nanowall induces metal-enhancedfluorescence, resulting in a maximum 7-fold enhancement of the fluorescencesignals. We also prepare QD nanostructures of various shapes and sizesby controlling the dry etching time. In the near future, this facileapproach can be used for fluorescence enhancement of colloidal QDswith plasmonic hybrid structures. Such structures can be used as opticalsubstrates for imaging applications and for fabrication of QD–LEDdevices. [ABSTRACT FROM AUTHOR]

Developing hydrogen (H2) sensors with a high sensitivity, rapid response, long-term stability, and high throughput is one of the critical issues in energy and environmental technology [Hübert et al. Sens. Actuators, B 2011, 157, 329]. To date, H2 sensors have been mainly developed using palladium (Pd) as the channel material because of its high selectivity and strong affinity to the H2 molecule [(Xu et al. Appl. Phys. Lett. 2005, 86, 203104), (Offermans et al. Appl. Phys. Lett. 2009, 94, 223110), (Yang et al. Nano Lett. 2009, 9, 2177), (Yang et al. ACS Nano 2010, 4, 5233), and (Zou et al. Chem. Commun. 2012, 48, 1033)]. Despite significant progress in this area, Pd based H2 sensors suffer from fractures on their structure due to hydrogen adsorption induced volumetric swelling during the α → β phase transition, leading to poor long-term stability and reliability [(Favier et al. Science 2001, 293, 2227), (Walter et al. Microelectron. Eng. 2002, 61-62, 555), and (Walter et al. Anal. Chem. 2002, 74, 1546)]. In this study, we developed a platinum (Pt) nanostructure based H2 sensor that avoids the stability limitations of Pd based sensors. This sensor exhibited an excellent sensing performance, low limit of detection (LOD, 1 ppm), reproducibility, and good recovery behavior at room temperature. This Pt based H2 sensor relies on a highly periodic, small cross sectional dimension (10-40 nm) and a well-defined configuration of Pt nanowire arrays over a large area. The resistance of the Pt nanowire arrays significantly decreased upon exposure to H2 due to reduced electron scattering in the cross section of the hydrogen adsorbed Pt nanowires, as compared to the oxygen terminated original state. Therefore, these well-defined Pt nanowire arrays prepared using advanced lithographic techniques can facilitate the production of high performance H2 sensors. [ABSTRACT FROM AUTHOR]

Parainfluenza virus infection is one of the causes of fatal rhabdomyolysis. Rhabdomyolysis can be aggravated by mitochondrial fatty acid β-oxidation disorders during prolonged periods of fasting. Moreover, in patients with late-onset isovaleric acidemia, hyperammonemia may occur following catabolic stress. In the present report, we describe a case of a 4-year-old boy with parainfluenza virus infection and late-onset isovaleric acidemia that rapidly progressed to coma, seizures, and cardiorespiratory collapse. His serum ammonia and creatinine kinase (CK) levels were 385 μMol/L and 23,707 IU/L, respectively. Continuous renal replacement therapy (CRRT) was initiated using continuous venovenous hemodiafiltration, after which the ammonia and CK levels returned to normal. Thus, we recommend the immediate initiation of CRRT in the management of patients with life-threatening rhabdomyolysis and hyperammonemia. [ABSTRACT FROM AUTHOR]

Abstract  Five strains (HYY0510-SK04, HYY0511-SK09, HYK0512-SK12, HYK0512-PK04 and HYY0512-PK05) of algicidal bacteria against the harmful bloom forming diatom Stephanodiscus hantzschii and dinoflagellate Peridinium bipes, were isolated. Among these strains, HYY0510-SK04, HYY0511-SK09 and HYK0512-SK12 have an effective algicidal activity for S. hantzschii, while HYK0512-PK04 and HYY0512-PK05 have an algicidal effect against P. bipes. Sequence analysis of 16S rDNA showed that HYY0510-SK04 and HYY0511-SK09 were closely related to Acidovorax delafieldii ATCC 17505T. HYK0512-SK12, HYK0512-PK04 and HYY0512-PK05 showed high homology with Variovorax paradoxus IAM 12373T (98.9%), Hydrogenophaga palleronii ATCC 49743T (98.8%) and Pseudomonas plecoglossicida ATCC 700383T (98.3%), respectively. HYY0510-SK04, HYY0511-SK09 and HYK0512-SK12 degraded S. hantzschii cells within two weeks when those bacteria were inoculated at densities of ≥107cells mL−1 to the lag or logarithmic growth phase of the algal culture. HYK0512-PK04 and HYY0512-PK05 degraded more than 90% of P. bipes cells within 14 and 8 days, respectively, when these bacteria were inoculated at densities of ≥107cells mL−1. Among the five bacterial strains, HYK0512-SK12 and HYY0512-PK05 showed the most effective growth inhibition of all the algae and cyanobacteria tested. Biochemical assays revealed that the main algicidal substance from all isolates were likely to be extracellular substances. These results indicate that the bacterial strains isolated for this study are potential agents for the control of harmful algal blooms in eutrophic reservoirs. [ABSTRACT FROM AUTHOR]

Objective: The adoption rate of electronic health record (EHR) systems in South Korea has continuously increased. However, in contrast to the situation in the United States (US), where there has been a national effort to improve and standardize EHR interoperability, no consensus has been established in South Korea. The goal of this study was to determine the current status of EHR adoption in South Korean hospitals compared to that in the US.Methods: All general and tertiary teaching hospitals in South Korea were surveyed regarding their EHR status in 2015 with the same questionnaire as used previously. The survey form estimated the level of adoption of EHR systems according to 24 core functions in four categories (clinical documentation, result view, computerized provider order entry, and decision supports). The adoption level was classified into comprehensive and basic EHR systems according to their functionalities.Results: EHRs and computerized physician order entry systems were used in 58.1% and 86.0% of South Korean hospitals, respectively. Decision support systems and problem list documentation were the functions most frequently missing from comprehensive and basic EHR systems. The main barriers cited to adoption of EHR systems were the cost of purchasing (48%) and the ongoing cost of maintenance (11%).Discussion: The EHR adoption rate in Korean hospitals (37.2%) was higher than that in US hospitals in 2010 (15.1%), but this trend was reversed in 2015 (58.1% vs. 75.2%). The evidence suggests that these trends were influenced by the level of financial and political support provided to US hospitals after the HITECH Act was passed in 2009.Conclusions: The EHR adoption rate in Korea has increased, albeit more slowly than in the US. It is logical to suggest that increased funding and support tied to the HITECH Act in the US partly explains the difference in the adoption rates of EHRs in both countries. [ABSTRACT FROM AUTHOR]

Developing large-area, single domainof organic soft-building blocks such as block copolymers, colloids,and supramolecular materials is one of the most important issues inthe materials science and nanotechnology. Owing to their small sizes,complex molecular architectures, and high mobility, supramolecularmaterials are not well-suited for building large area, single domainstructures. In the described study, a single domain of supramolecularcolumnar dendrimers was created over large area. The columnar structuresin these domains have smaller (4.5 nm) diameters, higher area densities(ca. 36 Tera-dots/in2) and larger domains (>0.1 ×0.1 mm2) than those of all existing BCP and colloidal assemblies.By simply annealing dendrimer thin films between two flat solid surfaces,single domains of hexagonal columnar structures are created over largemacroscopic areas. Observations made in this effort should serve asthe foundation for the design of new routes for bottom-up lithographybased on supramolecular building blocks. [ABSTRACT FROM AUTHOR]

Although Mycobacterium avium complex (MAC) is the most common pathogen in nontuberculous mycobacterial (NTM) pulmonary diseases, endobronchial lesions caused by MAC infections are very rare even in an immunocompromised host. Herein, we describe the case of a 59-year-old, HIV-negative and non-immunocompromised woman who developed multi-focal pulmonary infiltrations with endobronchial lesion caused by M. avium. Bronchoscopic examination revealed white- and yellow-colored irregular mucosal lesions in the bronchus of the left lingular division. M. avium was identified using sputum culture and bronchial washing fluid culture. Following the recommendations of the American Thoracic Society and Infectious Diseases Society of America (ATS/IDSA), the patient was begun on treatment with antimycobacterial drugs. After treatment, pneumonic infiltration decreased. [ABSTRACT FROM AUTHOR]

The article presents a case study of an older man who developed pseudoepitheliomatous keratotic and micaceous balanitis (PKMB) on his glans penis. It examines the patient's epidermis of PKMB and determines his human papillomavirus (HPV) through a broad-spectrum polymerase chain reaction (PCR) technique and restriction fragment mass polymorphism. It points out that he was treated with wide excision and was circumcised.