A Solution-Processable, Omnidirectionally Stretchable, and High-Pressure-Sensitive Piezoresistive Device.

The development of omnidirectionally stretchable pressure sensors with high performance without stretching-induced interference has been hampered by many challenges. Herein, an omnidirectionally stretchable piezoresistive pressure-sensing device is demonstrated by combining an omniaxially stretchable substrate with a 3D micropattern array and solution-printing of electrode and piezoresistive materials. A unique substrate structural design and materials mean that devices that are highly sensitive are rendered, with a stable out-of-plane pressure response to both static (sensitivity of 0.

An Omnidirectionally Stretchable Photodetector Based on Organic-Inorganic Heterojunctions.

Omnidirectionally stretchable photodetectors are limited by difficulties in designing material and fabrication processes that enable stretchability in multiaxial directions. Here, we propose a new approach involving an organic-inorganic p-n heterojunction photodetector comprised of free-standing ZnO nanorods grown on a poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate transport layer coated on a three-dimensional micropatterned stretchable substrate containing bumps and valleys. This structure allows for efficient absorption of stretching strain.

Microorganisms Causing Community-Acquired Acute Bronchitis: The Role of Bacterial Infection.

Background: Although acute bronchitis is quite common, there is relatively limited information regarding the microorganisms that are involved in this illness.

Methods: We performed a prospective study of acute bronchitis at 31 hospitals and clinics in Korea from July 2011 to June 2012. Sputum specimens were collected for polymerase chain reaction (PCR) and culture of microorganisms.

Mogul-Patterned Elastomeric Substrate for Stretchable Electronics.

A mogul-patterned stretchable substrate with multidirectional stretchability and minimal fracture of layers under high stretching is fabricated by double photolithography and soft lithography. Au layers and a reduced graphene oxide chemiresistor on a mogul-patterned poly(dimethylsiloxane) substrate are stable and durable under various stretching conditions. The newly designed mogul-patterned stretchable substrate shows great promise for stretchable electronics.

Role of Atypical Pathogens and the Antibiotic Prescription Pattern in Acute Bronchitis: A Multicenter Study in Korea.

The role of atypical bacteria and the effect of antibiotic treatments in acute bronchitis are still not clear. This study was conducted at 22 hospitals (17 primary care clinics and 5 university hospitals) in Korea. Outpatients (aged ≥ 18 yr) who had an acute illness with a new cough and sputum (≤ 30 days) were enrolled in 2013.

Transparent Stretchable Self-Powered Patchable Sensor Platform with Ultrasensitive Recognition of Human Activities.

Monitoring of human activities can provide clinically relevant information pertaining to disease diagnostics, preventive medicine, care for patients with chronic diseases, rehabilitation, and prosthetics. The recognition of strains on human skin, induced by subtle movements of muscles in the internal organs, such as the esophagus and trachea, and the motion of joints, was demonstrated using a self-powered patchable strain sensor platform, composed on multifunctional nanocomposites of low-density silver nanowires with a conductive elastomer of poly(3,4-ethylenedioxythiophene):polystyrenesulfonate/polyurethane, with high sensitivity, stretchability, and optical transparency. The ultra-low-power consumption of the sensor, integrated with both a supercapacitor and a triboelectric nanogenerator into a single transparent stretchable platform based on the same nanocomposites, results in a self-powered monitoring system for skin strain.

A Sensor Array Using Multi-functional Field-effect Transistors with Ultrahigh Sensitivity and Precision for Bio-monitoring.

Mechanically adaptive electronic skins (e-skins) emulate tactition and thermoception by cutaneous mechanoreceptors and thermoreceptors in human skin, respectively. When exposed to multiple stimuli including mechanical and thermal stimuli, discerning and quantifying precise sensing signals from sensors embedded in e-skins are critical. In addition, different detection modes for mechanical stimuli, rapidly adapting (RA) and slowly adapting (SA) mechanoreceptors in human skin are simultaneously required.

Evaluation of polygenic cause in Korean patients with familial hypercholesterolemia - A study supported by Korean Society of Lipidology and Atherosclerosis.

Background/objective: Familial hypercholesterolemia (FH) is an autosomal dominant disorder caused by mutations in LDLR, APOB, or PCSK9. Polygenicity is a plausible cause in mutation-negative FH patients based on LDL cholesterol (LDL-C)-associated single nucleotide polymorphisms (SNPs) identified by the Global Lipids Genetics Consortium (GLGC). However, there are limited data regarding the polygenic cause of FH in Asians.

Genetic testing of Korean familial hypercholesterolemia using whole-exome sequencing.

Familial hypercholesterolemia (FH) is a genetic disorder with an increased risk of early-onset coronary artery disease. Although some clinically diagnosed FH cases are caused by mutations in LDLR, APOB, or PCSK9, mutation detection rates and profiles can vary across ethnic groups. In this study, we aimed to provide insight into the spectrum of FH-causing mutations in Koreans.

Ultrahigh Responsivity in Graphene-ZnO Nanorod Hybrid UV Photodetector.

Ultraviolet (UV) photodetectors based on ZnO nanostructure/graphene (Gr) hybrid-channel field-effect transistors (FETs) are investigated under illumination at various incident photon intensities and wavelengths. The time-dependent behaviors of hybrid-channel FETs reveal a high sensitivity and selectivity toward the near-UV region at the wavelength of 365 nm. The devices can operate at low voltage and show excellent selectivity, high responsivity (RI ), and high photoconductive gain (G).

Piezoelectric coupling in a field-effect transistor with a nanohybrid channel of ZnO nanorods grown vertically on graphene.

Piezoelectric coupling phenomena in a graphene field-effect transistor (GFET) with a nano-hybrid channel of chemical-vapor-deposited Gr (CVD Gr) and vertically aligned ZnO nanorods (NRs) under mechanical pressurization were investigated. Transfer characteristics of the hybrid channel GFET clearly indicated that the piezoelectric effect of ZnO NRs under static or dynamic pressure modulated the channel conductivity (σ) and caused a positive shift of 0.25% per kPa in the Dirac point.

Epidemiological aspects of pertussis among adults and adolescents in a Korean outpatient setting: a multicenter, PCR-based study.

Epidemiological data of Bordetella pertussis infection among adolescents and adults are limited in Korea. Patients (≥ 11 yr of age) with a bothersome cough for less than 30 days were enrolled during a 1-yr period at 22 hospitals in Korea. Nasopharyngeal swabs were collected for polymerase chain reaction (PCR) and for bacteriologic culture.

A flexible bimodal sensor array for simultaneous sensing of pressure and temperature.

Diverse signals generated from the sensing elements embedded in flexible electronic skins (e-skins) are typically interfered by strain energy generated through processes such as touching, bending, stretching or twisting. Herein, we demonstrate a flexible bimodal sensor that can separate a target signal from the signal by mechanical strain through the integration of a multi-stimuli responsive gate dielectric and semiconductor channel into the single field-effect transistor (FET) platform.

Stability of pentacene thin film transistors under simultaneous mechanical bending and heating.

During the operational service of flexible electronic systems, component devices are subject to not only mechanical deformation but also environmental stimulation such as temperature and humidity. Therefore, the stability of flexible devices under simultaneous loading of multi-variable environmental factors including mechanical deformation needs to be studied. In this work, changes in device characteristics under simultaneous mechanical bending and heating of organic thin film transistors (OTFTs) were investigated in a mechanical bending system having capability of substrate heating.

Physically responsive field-effect transistors with giant electromechanical coupling induced by nanocomposite gate dielectrics.

Physically responsive field-effect transistors (physi-FETs) that are sensitive to physical stimuli have been studied for decades. The important issue for separating the responses of sensing materials from interference by other subcomponents in a FET transducer under global physical stimuli has not been completely resolved. In addition, challenges remain with regard to the design and employment of smart materials for flexible physi-FETs with a large electro-physical coupling effect.

Reduction of a grid moiré pattern by integrating a carbon-interspaced high precision x-ray grid with a digital radiographic detector.

The stationary grid commonly used with a digital x-ray detector causes a moiré interference pattern due to the inadequate sampling of the grid shadows by the detector pixels. There are limitations with the previous methods used to remove the moiré such as imperfect electromagnetic interference shielding and the loss of image information. A new method is proposed for removing the moiré pattern by integrating a carbon-interspaced high precision x-ray grid with high grid line uniformity with the detector for frequency matching.