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Department of Materials Science and EngineeringAfter the discovery of mechanically exfoliated graphene, there is an unprecedented increase in research on ultra-thin two-dimensional (2D) nanomaterials in the fields of nanotechnology, physics, chemistry, condensate physics, materials science, and biological sciences. Nowadays, a number of new 2D nanomaterials are discovered and widely studied, such as metal oxides, hexagonal boron nitride, transition metal dichalcogenides, 2D covalent organic frameworks, 2D metal-organic frameworks, black phosphorene, carbon nitride, and silicene. Among them, 2D metal oxides have unique structural properties because of their numerous low-coordinated surface dangling bonds and noticeable lattice structural distortion. 2D metal oxides also exhibit unique electric, mechanic, and catalytic performance owing to their ultrahigh surface-to-volume ratio and quantum confinement effects. Nowadays, there has been increasing studies that focus on 2D metal oxides, offering unprecedented opportunities in a variety of applications. However, the synthesis of 2D metal oxide nanosheets in a common and easy way is still a big challenge. This work mainly focused on atomically thin semiconducting metal oxide on graphene carries unique combination of adjustable band gaps, high charge carrier mobility, and optical transparency, which can be widely applied for opto-electronics, supercapacitors, rechargeable batteries and catalysis. But, study on the epitaxial formation and properties of metal oxide monolayer on 2D carbon layer remains unexplored due to hydrophobic 2D carbon surface and limits of conventional bulk deposition technique. Here, we report atomic scale study of heteroepitaxial growth and relationship of a single-atom-thick ZnO layer on graphene using atomic layer deposition. Among the metal oxide, we selected ZnO semiconductor as forms of epitaxial growth on 2D carbon substrate. Also, we demonstrate atom-by-atom growth of zinc and oxygen at the preferential zigzag edge of a ZnO monolayer on graphene through in situ observation. We experimentally determine that the thinnest ZnO monolayer has a wide band gap (up to 4.0 eV), due to quantum confinement and graphene-like structure, and high optical transparency. This study can lead to a new class of atomically thin two-dimensional heterostructures of semiconducting oxides formed by highly controlled epitaxial growth.ope

Soft, wireless periocular wearable electronics for real-time detection of eye vergence in a virtual reality toward mobile eye therapies

Ocular disorders are currently affecting the developed world, causing loss of productivity in adults and children. While the cause of such disorders is not clear, neurological issues are often considered as the biggest possibility. Treatment of strabismus and vergence requires an invasive surgery or clinic-based vision therapy that has been used for decades due to the lack of alternatives such as portable therapeutic tools. Recent advancement in electronic packaging and image processing techniques have opened the possibility for optics-based portable eye tracking approaches, but several technical and safety hurdles limit the implementation of the technology in wearable applications. Here, we introduce a fully wearable, wireless soft electronic system that offers a portable, highly sensitive tracking of eye movements (vergence) via the combination of skin-conformal sensors and a virtual reality system. Advancement of material processing and printing technologies based on aerosol jet printing enables reliable manufacturing of skin-like sensors, while a flexible electronic circuit is prepared by the integration of chip components onto a soft elastomeric membrane. Analytical and computational study of a data classification algorithm provides a highly accurate tool for real-time detection and classification of ocular motions. In vivo demonstration with 14 human subjects captures the potential of the wearable electronics as a portable therapy system, which can be easily synchronized with a virtual reality headset

A Case of Pathologic Splenic Rupture as the Initial Manifestation of Acute Myeloid Leukemia M2

A pathologic splenic rupture refers to a rupture without trauma. A splenic rupture as the initial manifestation of acute myeloid leukemia is extremely rare. In this study, we described a rare case of acute myeloid leukemia presenting principally as an acute abdomen due to a pathologic splenic rupture in a 35-year old male patient. We can assert that a pathologic splenic rupture in hematologic diseases is a potentially life-threatening complication, which necessitates immediate operative intervention. Any such patient complaining about left upper abdominal tenderness should be closely observed, and further diagnostic investigations (ultrasonograph of the abdomen, abdominal CT scan) should be initiated in order to rule out a splenic rupture. The oncologist should be aware of this rare initial presentation of acute myeloid leukemia (AML) M2, as the condition generally necessitates a prompt splenectomy

β-Glucan enhanced apoptosis in human colon cancer cells SNU-C4

The apoptotic effect of bacteria-derived β-glucan was investigated in human colon cancer cells SNU-C4 using terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay, reverse transcription-polymerase chain reaction (RT-PCR) expressions of Bcl-2, Bax, and Caspase-3 genes, and assay of caspase-3 enzyme activity. β-Glucan of 10, 50, and 100 µg/mL decreased cell viability in a dose-dependent manner with typical apoptotic characteristics, such as morphological changes of chromatin condensation and apoptotic body formation from TUNEL assay. In addition, β-glucan (100 µg/mL) decreased the expression of Bcl-2 by 0.6 times, whereas the expression of Bax and Caspase-3 were increased by 3.1 and 2.3 times, respectively, compared to untreated control group. Furthermore, the caspase-3 activity in the β-glucan-treated group was significantly increased compared to those in control group (P < 0.05). Bacterial derived β-glucan could be used as an effective compound inducing apoptosis in human colon cancer

Self-esteem as a Moderator of the Effects of Happiness, Depression, and Hostility on Suicidality Among Early Adolescents in Korea

Objectives The purpose of this study was to investigate the role of self-esteem as a moderator of the factors influencing suicidality among middle-schoolers. Methods Moderated multiple regression analysis was applied to assess the influence of happiness, depression, and hostility on suicidality and to determine the degree to which self-esteem served as a moderator of those relationships. Data were collected from 268 students at a middle school in Busan, Korea, using a self-administered structured questionnaire. Results Happiness, depression, and hostility had significant direct effects on suicidality. Self-esteem showed no direct effect, but had a significant moderating effect on the relationship between hostility and suicidal behavior. Conclusions These results suggest that various interventions, such as counseling programs, should be designed to alleviate hostility and depression and to enhance happiness and self-esteem among early adolescents

Clinical significance of preoperative serum vascular endothelial growth factor, interleukin-6, and C-reactive protein level in colorectal cancer

<p>Abstract</p> <p>Background</p> <p>Angiogenesis is a multistep process in which many growth factors and cytokines have an essential role. Vascular endothelial growth factor (VEGF) is a potent angiogenic agent that acts as a specific mitogen for vascular endothelial cells through specific cell surface receptors. The interleukin-6 (IL-6) pathway is another mechanism linking angiogenesis to malignancy. C-reactive protein (CRP), a representative marker for inflammation, is known for its association with disease progression in many cancer types. The aim of this study was to determine preoperative serum levels of VEGF, IL-6, and CRP in colorectal carcinoma, and to correlate them with disease status and prognosis.</p> <p>Methods</p> <p>A 132 of 143 patients who underwent curative resection for colorectal cancer were enrolled in this study. 11 patients with resection margin positive were excluded. Factors considered in analysis of the relationship between VEGF, IL-6, and CRP and histological findings. Patient prognosis was investigated. Serum levels of VEGF and IL-6 were assessed using Enzyme-Linked Immuno-Sorbent Assay (ELISA), and CRP was measured using immunoturbidimetry.</p> <p>Results</p> <p>Median follow-up duration was 18.53 months (range 0.73-43.17 months) and median age of the patients was 62 years (range, 26-83 years). Mean and median levels of VEGF and CRP in colorectal cancer were significantly higher than in the normal control group; 608 vs. 334 pg/mL and 528 (range 122-3242) vs. 312 (range 16-1121) (<it>p </it>< 0.001); 1.05 mg/dL vs. 0.43 mg/dL and 0.22 (range 0.00-18.40) vs. 0.07 (range 0.02-6.94) (<it>p </it>= 0.002), respectively. However mean and median level of IL-6 in patients were not significantly higher than in control; 14.33 pg/mL vs. 5.65 pg/mL and 6.00 (range 1.02-139.17) vs. 5.30 (4.50-13.78) (<it>p </it>= 0.327). Although IL-6 and CRP levels were not correlated with other pathological findings, VEGF level was significantly correlated with tumor size (<it>p </it>= 0.012) and CEA (<it>p </it>= 0.038). When we established the cutoff value for VEGF (825 pg/mL), IL-6 (8.09 pg/mL), and CRP (0.51 mg/dL) by Receiver Operating Characteristic (ROC) curve, we noted that high VEGF levels tended to reduce overall survival (<it>p </it>= 0.053), but not significantly. However, IL-6 and CRP demonstrated no significance with regard to disease free survival (<it>p </it>= 0.531, <it>p </it>= 0.701, respectively) and overall survival (<it>p </it>= 0.563, <it>p </it>= 0.572, respectively). Multivariate analysis showed that VEGF (<it>p </it>= 0.032), CEA (<it>p </it>= 0.012), lymph node metastasis (<it>p </it>= 0.002), and TNM stage (<it>p </it>= 0.025) were independently associated with overall survival.</p> <p>Conclusions</p> <p>Preoperative serum VEGF and CRP level increased in colorectal cancer patients. High VEGF level has been proposed as a poor prognostic factor for overall survival in patients with colorectal cancer.</p

Stent Fracture at the Proximal Shaft of the Left Main Stem

Stent fracture is likely to be caused due to mechanical stress at the hinge point or kinking movement at the point of aneurysm formation with stent malapposition. To our knowledge, this is the first published report of stent fracture at the proximal shaft of the left main stem in a patient with acute myocardial infarction