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Refugees commonly experience difficulties with emotional processing, such as alexithymia, due to stressful or traumatic experiences. However, the functional connectivity of the amygdala, which is central to emotional processing, has yet to be assessed in refugees. Thus, the present study investigated the resting-state functional connectivity of the amygdala and its association with emotional processing in North Korean (NK) refugees.
This study included 45 NK refugees and 40 native South Koreans (SK). All participants were administered the Toronto Alexithymia Scale (TAS), Beck Depression Inventory (BDI), and Clinician-administered PTSD Scale (CAPS), and differences between NK refugees and native SK in terms of resting-state functional connectivity of the amygdala were assessed. Additionally, the association between the strength of amygdala connectivity and the TAS score was examined.
Resting-state connectivity values from the left amygdala to the bilateral dorsolateral prefrontal cortex (dlPFC) and dorsal anterior cingulate cortex (dACC) were higher in NK refugees than in native SK. Additionally, the strength of connectivity between the left amygdala and right dlPFC was positively associated with TAS score after controlling for the number of traumatic experiences and BDI and CAPS scores.
The present study found that NK refugees exhibited heightened frontal–amygdala connectivity, and that this connectivity was correlated with alexithymia. The present results suggest that increased frontal–amygdala connectivity in refugees may represent frontal down-regulation of the amygdala, which in turn may produce alexithymia.
Family study can provide estimates of overall genetic influences on a particular trait because family relationships provide accurate measures of average genetic sharing. However, evidence of genetic contributions to skin phenotypes is limited, which may preclude genetic studies to identify genetic variants or to understand underlying molecular biology of skin traits. This study aimed to estimate genetic and environmental contributions to selected dermatologic phenotypes, that is, to melanin index, sebum secretion, and skin humidity level in a Korean twin-family cohort. We investigated more than 2,000 individuals from 486 families, including 388 monozygotic twin pairs and 82 dizygotic twin pairs. Variance component method was used to estimate genetic influences in terms of heritability. Heritability of skin melanin index, sebum secretion, and skin humidity (arm and cheek) were estimated to be 0.44 [95% CI 0.38–0.49], 0.21 [95% CI 0.16–0.26], 0.13 [95% CI 0.07–0.18], and 0.11 [95% CI 0.06–0.16] respectively, after adjusting for confounding factors. Our findings suggest that genetics play a major role on skin melanin index, but only mild roles on sebum secretion and humidity. Sebum secretion and skin humidity are controlled predominantly by environmental factors notably on shared environments among family members. We expect that our findings add insight to determinants of common dermatologic traits, and serve as a reference for biologic studies.
During the past decade, carbapenemase-producing Enterobacteriaceae (CPE) has emerged and spread across the world.1 The major carbapenemase enzymes currently being reported are KPC, NDM-1, VIM, IMP, and OXA.2 Because carbapenemase can be effectively transmitted via mobile genetic elements, and current therapeutic options for CPE infections are extremely limited, CPE may be one of the most serious contemporary threats to public health. However, very little is known about the characteristics of CPE carriage during hospitalization. The aims of this study were to investigate the clearance rate of CPE carriage and determine the number of consecutive negative cultures required to confirm CPE clearance. We also examined CPE transmission among hospitalized patients.
Infect. Control Hosp. Epidemiol. 2015;36(11):1361–1362
Decreased hemoglobin levels increase the risk of developing dementia among the elderly. However, the underlying mechanisms that link decreased hemoglobin levels to incident dementia still remain unclear, possibly due to the fact that few studies have reported on the relationship between low hemoglobin levels and neuroimaging markers. We, therefore, investigated the relationships between decreased hemoglobin levels, cerebral small-vessel disease (CSVD), and cortical atrophy in cognitively healthy women and men.
Cognitively normal women (n = 1,022) and men (n = 1,018) who underwent medical check-ups and magnetic resonance imaging (MRI) were enrolled at a health promotion center. We measured hemoglobin levels, white matter hyperintensities (WMH) scales, lacunes, and microbleeds. Cortical thickness was automatically measured using surface based methods. Multivariate regression analyses were performed after controlling for possible confounders.
Decreased hemoglobin levels were not associated with the presence of WMH, lacunes, or microbleeds in women and men. Among women, decreased hemoglobin levels were associated with decreased cortical thickness in the frontal (Estimates, 95% confidence interval, −0.007, (−0.013, −0.001)), temporal (−0.010, (−0.018, −0.002)), parietal (−0.009, (−0.015, −0.003)), and occipital regions (−0.011, (−0.019, −0.003)). Among men, however, no associations were observed between hemoglobin levels and cortical thickness.
Our findings suggested that decreased hemoglobin levels affected cortical atrophy, but not increased CSVD, among women, although the association is modest. Given the paucity of modifiable risk factors for age-related cognitive decline, our results have important public health implications.
The present study was performed to investigate whether breast-feeding is associated with early pubertal development among children 7–9 years old in Korea.
Children were divided into those who did and did not receive breast-feeding for 6 months or longer in accordance with the recommendations of the WHO. Pubertal status was determined by clinical examination using Tanner staging.
Prospective observational study.
We conducted a follow-up study of children aged 7–9 years in 2011 who had taken part in the Ewha Birth & Growth Cohort study.
Fifty (22·8 %) of the total of 219 children were in early puberty, with the proportion being slightly higher for girls (24·1 %) than boys (21·4 %). Children who had entered early puberty were taller, weighed more and had a higher concentration of insulin-like growth factor 1. Moreover, the change in weight Z-score from birth to follow-up was significantly lower in children who were breast-fed than in those who were not (weight Z-score change: 0·32 (sd 1·59) v. 0·77 (sd 1·61), respectively, P=0·04). Comparison of breast-feeding by puberty status indicated a preventive association with early puberty in children who were breast-fed for 6 months or longer (OR=0·37; 95 % CI 0·18, 0·74). This association remained significant after adjustment for relevant covariates.
These results demonstrate a beneficial association between breast-feeding and early pubertal development, especially in those breast-fed for 6 months or longer. The study suggests that interventions would need to start early in life to prevent early pubertal development.
Cataract, defined as opacity of the lens in one or both eyes, is a major cause of blindness throughout the world, and not uncommon, particularly in the elderly population. However, congenital cataracts are rare and occur with a frequency of 30 cases in 100,000 births. About one-third of the cases fall into the group inherited without systemic abnormality. Importantly, congenital cataracts produce deprivation amblyopia, refractive amblyopia, and retinal detachment, leading to lifelong visual impairment. Successful management is dependent on early diagnosis and referral for surgery when indicated. Here we present a case of hereditary bilateral cataracts in a dizygotic twin detected on prenatal ultrasound examinations and postnatally confirmed as congenital cataracts associated with posterior lenticonus.
The crystallization of amorphous silicon thin films by electron beam exposure was studied. Amorphous silicon and silicon dioxide layers were deposited on glass substrate by PECVD at 360 °C. The optimization to crystallize 300 nm thick amorphous silicon film was carried out at a RF power of 300 W, DC voltage of 1500 V, Argon gas flow rate of 3 sccm and a distance between electron beam mesh and sample of 40 mm. High quality nano-crystalline silicon films with an activation energy of 0.47 eV from conductivity, a grain size of 15–45 nm from SEM and Raman crystalline volume fraction of 93.1% were fabricated. We expect that e-beam exposure will be applied to crystallization of amorphous silicon films.
Adiponectin has been associated with insulin resistance and type 2 diabetes mellitus and possibly fetal growth. Our aim was to assess the association between the single nucleotide polymorphisms (SNPs) of the adiponectin gene (ADIPOQ) and the birth sizes. We investigated four SNPs of ADIPOQ (rs182052, rs2241766, rs1501299, and rs266729) and birth height and weight in 237 healthy full-term neonates. The neonates with the rs182052 G allele had a greater birth weight (p = .043 in the dominant model) and a higher ponderal index (p = .028 in the additive model). The rs2241766 G allele was associated with a greater birth weight (p = .016 in the recessive model). In a logistic regression analysis, the homozygotes for the rs182052 G allele and those for the rs2241766 G allele showed a significant association with a greater birth weight above 90 percentile (OR 2.75, 95% CI 1.13–6.70 and OR 5.15, 95% CI 1.66–15.99, respectively). In conclusion, we found an association between rs182052 and rs2241766 and birth weight and ponderal index among healthy neonates and suggested that adiponectin might have some roles in fetal growth.
Stream development can generate environmental changes that impact fish communities. In temperate streams, the distribution of fish species is associated with environmental gradients. To analyze the relevant factors, large-scale exploration is required. Thus, to evaluate the distribution patterns of fish in Korea, sampling was conducted on a national scale at 720 sites over a 6-week period in 2009. A total of 124 fish species in 27 families were identified; Zacco platypus and Zacco koreanus of the Cyprinidae were the dominant and subdominant species, respectively. Of the species found, 46 (37.1%) were endemic and 4 (3.2%) exotic; of the latter, Micropterus salmoides and Lepomis macrochirus were widely distributed. Upon canonical correspondence analysis (CCA), both altitude and biological oxygen demand (BOD) were highly correlated with CCA axes 1 and 2, respectively. This explained 62.5% of the species–environment relationship. Altitude and stream order were longitudinally related to species distribution. The numbers of both total and endemic species gradually increased as streams grew in size to the fourth–fifth-order, and decreased in sixth-order, streams. Overall, fish communities were stable throughout the entire watershed, whereas some species showed site-specific occurrence patterns due to the paleogeomorphological characteristics of Korean peninsula. However, various anthropogenic activities may negatively affect fish communities. Therefore, both short- and long-term sustainable management strategies are required to conserve native fish fauna.
Dichlorosilane based CVD WSix is deposited by the reaction of tungsten fluoride (WF6) and dichlorosilane (SiH2Cl2; DCS). The reaction is thermodynamically favorable and results in WSix film with less fluorine (F) concentration than monosilane (SiH4; MS) based WSix. DCS based WSix shows less expansion of gate oxide and better step coverage than monosilane based WSix. Due to its DCS based stable film stoichiometry, WSix has low resistivity and therefore has been widely applied in ULSI memory devices. However, DCS is a source of chlorine, which is a major impurity. This means special considerations have to be made when using DCS based WSix in comparison with MS based WSix. This work provides evaluation and control of chlorine behaviors in DCS based WSix film.
Sources for low frequency noise in polycrystalline silicon thin-film transistors are analytically investigated. The grain boundary is modeled as symmetric Schottky barrier and a new device equation for current conduction in thin-film transistors is presented. At lower currents where barrier height is large enough to provide necessary distribution of time constants for 1/f noise, the number fluctuation via barrier height modulation at the grain boundary is found to be the main noise generation mechanism. At higher currents, mobility and diffusivity fluctuation are found to be dominant
The effects of reactive ion etching damage on the electrical properties of Pt/SBT/Pt capacitors have been investigated. The plasma treated SBT/Pt layers showed a significant decrease in remanent polarization compared with that of the reference sample. The remanent polarization of the plasma treated layers varied with the gas ratios of the Cl2/Ar plasma. XPS analysis of the plasma treated SBT/Pt samples showed that the surface composition was significantly changed as the gas ratios were varied, which resulted in a polarization decrease in the plasma treated samples. Plasma treatment also caused a voltage shift of the hysteresis loops along the voltage axis. The magnitude of the voltage shift was increased for the chlorine-rich plasma. The results of surface analysis revealed that the voltage shift is caused by oxygen deficiency at the SBT surface. Based on our experimental results, reactive ion etching damage was explained in terms of physical and electrical effects of the plasma on the electrical properties of the ferroelectric Pt/SBT/Pt capacitors.
Strip-shaped diamond-tip field emitter array was fabricated by using the transfer mold technique. The sharp turn-on characteristic was observed from the current-voltage measurement of the fabricated diamond-tip field emitter array. The turn-on characteristic of the diamond-tip field emitter array was compared with that of a flat diamond film. High emission current density was obtained from the diamond-tip field emitter array. The threshold voltage of the diamond-tip field emitter array was lower than that of a flat diamond film.
GaN epitaxial thin films were grown on a nitridated sapphire at low temperature (550°C) using remote plasma enhanced ultrahigh vacuum chemical vapor deposition system and these films were investigated by Rutherford backscattering spectroscopy (RBS), X-ray diffraction(XRD) θ-rocking technique and the Ultraviolet-Visible-Nearinfrared (UV-VIS-NIR) absorption spectrum. The FWHM of the X-ray θ-rocking curve was about 0.4 degree using the (0002) reflection from the GaN layer with 5000Å thickness grown on the nitridated sapphire. An analysis of XRD and the UV-VIS-NIR absorption spectrum showed that the crystalline and optical qualities of GaN are dependent on the nitridation time of the sapphire even at low temperature when a plasma source is used for nitridation. This means that the density of protrusion, which is formed by a relaxation of the elastic energy caused by the lattice difference between the sapphire and AlxO1-xN, with the sapphire nitridation time plays a key role in the crystalline and optical properties of grown GaN films. The RBS channeling data and the FWHM value of the θ-rocking curve for GaNr(0002) also indicated that the truncated hexagonals are tilted towards each other. These results showed that the GaN epitaxial film can be successfully grown on nitridated sapphire by RPE-UHVCVD even at low temperature.
We fabricated InAs self-assembled quantum dots (QDs) on strained layer using molecular beam epitaxy. The strained layer consisted of InAs/GaAs superlattice(SL) and GaAs barrier layer on (001) GaAs substrate. Through controlling thickness of the strained layer, we formed two-dimensional alignments of QDs on misfit dislocation arrays along <110> directions made by strained layer. The increase of the strained layer thickness resulted in a stronger alignment of QDs, which were observed by atomic force microscopy studies. The aligned QDs were confirmed to confine carriers well and have different size distributions by photoluminescence measurement.
Both the wafer fusion and the heteroepitaxy technology were used successfully to obtain high quality GaAs layer on the InP substrate where the lattice mismatch was 3.7 %. The enhancement of the lateral growth rate was a crucial factor for the formation of high quality QWR in the patterned fusion layer. This technique can provide a way of overcoming the limitation of heteroepitaxy caused by misfit problems and its subsequent quality degradation. It is expected that the overgrowth technique on the patterned fusion layer can be applicable to the photonic device fabrication on the other substrate such as Si.
Zinc oxide (ZnO) thin films have emerged as one of the most promising oxide materials owing to their optical and electrical properties, together with their high chemical and mechanical stability. Chemical solution deposition (CSD) is attractive technique for obtaining ZnO thin films and has the advantages of easy control of the film composition and easy fabrication of a larger-area thin film at low cost. In this work, epitaxial ZnO thin films on SiC substrate were prepared by using a CSD method with a zinc naphthenate precursor. Precursor films were pyrolyzed at 500°C for 10 min in air and finally annealed at 600°C, 700°C, 800°C and 900°C for 30 min in air. Crystallinity and in-plane alignment of the films were investigated by X-ray diffraction theta-2 theta scan and pole-figure analysis. Scanning electron microscope, scanning probe microscope, and He-Cd laser (325 nm) are used to detect the surface morphology and photoluminescence of the films. The effects of annealing temperature on crystallinity and epitaxy of the films will be fully discussed on the basis of the results of X-ray diffraction analysis.
The adhesion force of pad and alumina were experimentally and theoretically investigated in slurry solutions of different pHs. The isoelectric point (IEP) of pad particles was measured to be around pH 3. The wafer surfaces showed negative zeta potentials in the investigated pH ranges with exception of FSG and Ta. Cu and Ta showed higher interaction forces than dielectric materials. The lowest adhesion force was measured between pad particle and wafer surfaces in a slurry solution of pH 11. The magnitude of adhesion force of pad particles was lower than alumina particles.
A new shift register using p-type poly-Si thin-film transistors (TFTs) for active matrix display is proposed. It utilizes only p-type TFTs to simplify the fabrication process, and provides time-shifted output signals with a voltage swing from VSS to VDD without signal-level loss. In the proposed shift register, output is structurally separated from carry and therefore has a high immunity to output signal distortion caused by output load capacitance. We also propose a new light emitting control method using this shift register for high image quality active-matrix organic light emitting diode (AMOLED) displays. The proposed shift register was verified by simulation and measurement.