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This paper considers a variant of the bandwidth packing problem that determines paths for selected demands on a telecommunication network with given arc capacities to maximize the total revenue. Facilities on the arcs can be seen as M/M/1 queuing systems, which incur queuing delays that should be minimized by adding them to the objective function as a penalty. We also consider the case in which the demands are uncertain, so both the capacity and queuing delay of an arc should take the uncertainty of demand into account. The mathematical formulation for the problem is stated as a nonlinear integer programming problem due to the queuing delays added in the objective function. We first show that the formulation can be linearized to a mixed integer linear programming problem that can be solved by off-the-shelf MIP solvers like Cplex. We then propose a branch-and-price approach by showing that the column generation problem can be solved efficiently by a dynamic programming algorithm. Computational experiments with benchmark instances show that the proposed approach significantly outperforms the state-of-the-art MIP solver in terms of computational times. We also report a Monte-Carlo simulation study with randomly generated demand scenarios to assert the benefits of the robust approach.

Background So far, studies on the association between sleep and periodontitis have shown conflicting results. This study assessed the association among sleep duration, sleep time, and periodontitis among a nationally representative Korean population and the mediation effect of WBC. Methods We analyzed data from the Seventh Korean National Health and Nutrition Examination Survey (KNHANES VII) collected from 2016 to 2018. With the screenings by age (45 to 64), edentate, and the adequacy of information provided, the analysis was confined to a selected group of respondents of 4407 with measurements for the sleep survey and periodontal health status out of total 24,269. Periodontitis was defined according to the World Health Organization's community periodontal index (CPI) code greater than or equal to three, and severe periodontitis was defined as CPI code 4. Multivariable logistic regression analysis was used to test the association between sleep and periodontitis controlling the confounding factors. Results Those who went to bed during the daytime were associated with periodontitis (OR = 1.49, 95% confidence interval [CI]: 1.07 to 2.07). In a combined sleep time and duration model, those who went to bed at night with a sleep duration of 9 hours or more were associated with periodontitis (OR = 1.69, 95% CI: 1.04 to 2.77) and severe periodontitis (OR = 1.88, 95% CI: 1.02-3.45). WBC count had the highest impact on the association between sleep time and periodontitis. Conclusions Our findings suggest that an extra-long sleep duration and going to bed during the daytime are associated with periodontitis.

Delafossite oxide CuAlO

To investigate the efficacy of exercise intervention using a real-time video conferencing platform (ZOOM) on inter-recti distance, abdominal muscle thickness, static trunk endurance, and maternal quality of life, 37 women with diastasis recti between six months and one year postpartum were randomly divided into the online (n = 19) and offline (n = 18) groups. The online group underwent 40-min trunk stabilization exercise sessions twice a week for six weeks, through a real-time video conference platform, while the offline group attended the same program in person. The inter-recti distance and muscle thickness between the abdominal muscles were measured by rehabilitation ultrasound imaging, the Torso endurance test was used to compare the static trunk endurance, and the maternal quality of life questionnaire (MAPP-QOL, score) was applied. Significant improvements were observed in the inter-recti distance between the rectus abdominis, abdominal muscle thickness, static trunk endurance, and maternal quality of life in both groups (p < 0.001); a more significant improvement was observed in the offline group. No significant differences were observed between groups except for the left rectus abdominis thickness and Psychological/Baby and Relational/Spouse-Partner subscale in the maternal quality of life index (p > 0.05). Exercise interventions delivered in a real-time videoconferencing platform are effective at improving the inter-recti distance, trunk stability, and quality of life in postpartum women and may be an alternate to face-to-face intervention.

Black phosphorus has been recently suggested as a very promising material for use in 2D field-effect transistors. However, due to its poor stability under ambient conditions, this material has not yet received as much attention as for instance MoS2. We show that the recently demonstrated Al2O3 encapsulation leads to highly stable devices. In particular, we report our long-term study on highly stable black phosphorus field-effect transistors, which show stable device characteristics for at least eight months. This high stability allows us to perform a detailed analysis of their reliability with respect to hysteresis as well as the arguably most important reliability issue in silicon technologies, the bias-temperature instability. We find that the hysteresis in these transistors depends strongly on the sweep rate and temperature. Moreover, the hysteresis dynamics in our devices are reproducible over a long time, which underlines their high reliability. Also, by using detailed physical models for oxide traps...

Polymer FETs generally have a wide subthreshold regime due to a lot of disorder, mainly originated from domain/grain boundaries. Deep state’s charge transport of polymer transistors has not been investigated due to the difficulty in determining the field-effect mobility in the subthreshold region. In this paper, the features of the charge transport in deep and shallow states of polymer transistors will be discussed in detail through an accurate modeling and an analysis of subthreshold behavior in transistors. Charge transport in shallow states can be described by multiple trap and release transport, while hopping transport models, such as variable range hopping or Gaussian disorder-based model, describe well the deeper state’s charge transport. In addition, the transition between the conduction regimes is a function of temperature and carrier density.

Background and Aims Smartphone addiction is a recent concern that has resulted from the dramatic increase in worldwide smartphone use. This study assessed the risk and protective factors associated with smartphone addiction in college students and compared these factors to those linked to Internet addiction. Methods College students (N = 448) in South Korea completed the Smartphone Addiction Scale, the Young’s Internet Addiction Test, the Alcohol Use Disorders Identification Test, the Beck Depression Inventory I, the State–Trait Anxiety Inventory (Trait Version), the Character Strengths Test, and the Connor–Davidson Resilience Scale. The data were analyzed using multiple linear regression analyses. Results The risk factors for smartphone addiction were female gender, Internet use, alcohol use, and anxiety, while the protective factors were depression and temperance. In contrast, the risk factors for Internet addiction were male gender, smartphone use, anxiety, and wisdom/knowledge, while the protective factor was courage. Discussion These differences may result from unique features of smartphones, such as high availability and primary use as a tool for interpersonal relationships. Conclusions Our findings will aid clinicians in distinguishing between predictive factors for smartphone and Internet addiction and can consequently be utilized in the prevention and treatment of smartphone addiction.

The aim of this study was to evaluate the chemical quenching system for residual ozone and to determine the operating condition for the quenching system. Hydrogen peroxide (H2O2) and sodium thiosulfate (Na2S2O3) were investigated as quenching reagents for ozone removal, and the tendency of each chemical was notably different. In the case of H2O2, the degradation rate of ozone was increased as the concentration of H2O2 increase, and temperature and pH value have a significant effect on the degradation rate of ozone. On the other hand, the degradation rate of ozone was not affected by the concentration of Na2S2O3, temperature and pH value, due to the high reactivity between the S2O3 2- and ozone. This study evaluates the decomposition mechanism of ozone by H2O2 and Na2S2O3 with consideration for the water quality and reaction time. Furthermore, the removal test for the quenching reagents, which can be remained after reaction with ozone, was conducted by GAC process.

We describe the device and transport characteristics of amorphous zinc tin oxide thin-film (ZTO) transistors. In samples with a sufficiently high mobility and at a high gate voltage, a crossover occurs from transport governed by thermal excitation of trapped charges to one where the charge carriers reside for a sufficiently long time in extended states. Very few semiconductors exhibit this range of behavior in the same device under different conditions. We also describe the correct methods to extract mobility values and ionization energies from current voltage characteristics.

Here we report on dramatic and favorable changes to the operating characteristics in monolayer graphene field-effect transistors (FETs) exposed to vapor-phase, polar organic molecules in ambient. These changes include significant reduction of the Dirac voltage, accompanied by both an increase in electron and hole mobility, μ, and a decrease in residual carrier density, N0, to3 × 10(11) cm(-2). In contrast to graphene FET modulation with various liquid- and solid-phase dielectric media present in the literature, we attribute these changes to screening by polar vapor-phase molecules of fields induced by charged impurities and defects, n(imp), in or near the active layer. The magnitude of the changes produced in the graphene FET parameters scales remarkably well with the dipole moment of the delivered molecules. These effects are reversible, a unique advantage of working in the vapor phase. The changes observed upon polar molecule delivery are analogous to those produced by depositing and annealing fluoropolymer coatings on graphene that have been reported previously, and we attribute these changes to similar charge screening or neutralization phenomena.

In mammals, either enhancer of zeste homologue 2 (EZH2) or its homolog EZH1 functions as the catalytic subunit of polycomb repressive complex 2 (PRC2), and plays an essential role for the maintenance of transcriptional repression by the trimethylation of histone H3 lysine 27 (H3K27me3). Hyperinduction of H3K27me3 mediated by EZH2 overexpression or EZH2 gain-of-function (GOF) mutation (e.g. Y641, A677 and A687) has been associated with lymphoma and myeloma progression. Many publications suggest that suppressing PRC2 activity by EZH2 inhibition is a potential therapeutic target for hematological malignancies. Up to date, there are known a few EZH2 selective inhibitors with showing anti-tumor activity in some preclinical and clinical studies. However, the inhibition of EZH2 can complementarily induce EZH1 activation, which reactivates PRC2 function in turn. Therefore, dual inhibition of EZH1 and EZH2 could give more effective than EZH2 inhibition alone in blocking PRC2 function as an anti-cancer therapy. Herein, we introduce a novel EZH1/2 dual inhibitor, HM97594, which simultaneously inhibits the methyltransferase activity of wild-type EZH1 as well as wild-type and GOF mutant EZH2 at nanomolar concentrations. HM97594 potently repressed trimethylation of H3K27 in lymphoma and myeloma cell lines. As a result, HM97594 showed broader and stronger activities than EZH2 selective inhibitors in in vitro studies of inhibiting the proliferation of various hematological cancer cell lines. HM97594 induced the differentiation of DLBCL to plasma cells with an increment of cell lineage specific markers (e.g. PRDM1, IRF4 and CD38) and decreased the colony forming ability. Also, HM97594 caused cell cycle G0/1 arrest and apoptosis in KARPAS-422 cells harboring EZH2 Y641 GOF mutation. In addition, HM97594 showed potent antitumor activity in KARPAS-422 lymphoma cell xenograft mouse model. Once daily orally administered HM97594 greatly inhibited tumor growth in a dose-dependent manner without body weight loss compared to the known EZH2 inhibitor. Collectively, it was demonstrated in the present studies that HM97594, EZH1/2 dual inhibitor, has promising potential as an anticancer drug for patients with subtypes of hematological malignancies. Further preclinical studies will be performed and reported soon after the establishment of a preclinical candidate. Disclosures No relevant conflicts of interest to declare.

Graphene Nanoribbons (GNR) are been being investigated as they possess a bandgap in contrast to graphene sheets which have zero bandgap [1, 2]. Therefore, GNR might be more suitable as a channel material in field-effect transistors (FETs) which requires a high on/off ratio. The other electrical properties of GNR FETs apart from on/off ratio, however, are not as good as those of corresponding graphene sheet FETs. Most GNR FETs have a larger hysteresis, a lower mobility and a larger Dirac voltage than those of graphene sheet FETs. The critical factor that results in degraded performance of GNR FET is edge defects, since GNR due to their geometry have a larger number of edges per active channel width. Moreover, edges of patterned GNR from chemical vapor deposition (CVD) grown graphene do not have a perfect chirality and inevitably have more broken bonds. Thus defect passivation or amelioration assumes considerable importance if the excellent potential of GNR as a semiconducting material is to be realized. In this abstract we report the effect of polar vapors on the electrical characteristics of GNR FET, which is fabricated via patterning from CVD grown graphene monolayer sheet. Our goal is to use these as model studies in designing suitable cap layers that both protect the nanoribbons from the ambient and favorably influence, to a considerable degree, their electrical properties.

We analyzed the changes in electrical and optical characteristics of 1 multiple-quantum-well (MQW) blue LEDs grown on a c-plane sapphire substrate after a stress test. Experiments were performed by injecting 50 mA current for 200 hours to TO-CAN packaged sample chips. We selected the value of injection current for stress through the junction-temperature measurement by using the forward-voltage characteristics of a diode to maintain a sufficiently low junction temperature during the test. The junction temperature at the selected injection current of 50 mA was 308 K. Experiments were performed under the assumption that the average junction temperature of 308 K did not affect the characteristics of the ohmic contact and the GaN-based materials. Before and after the stress test, we measured and analyzed current-voltage, light-current, light distribution on the LED surface, wavelength spectrum and relative external quantum efficiency (EQE). After the stress test, it was observed experimentally that the optical power and the relative EQE decreased. We theoretically investigated and experimentally proved that these phenomena are due to the increased nonradiative recombination rate caused by the increased defect density.

Inverters were fabricated with pentacene organic thin film transistors (OTFTs) using inkjet printing method. The gate, source and drain electrodes were printed with Ag ink. The mobility and threshold voltage of the bottom-contact OTFT were 0.078 cm2/Vs and 2.8 V, respectively. Printed inverters operated well in 200 Hz at VDD = −20 V.

We report the electrode-area dependence of the high-frequency characteristics of polymer diodes fabricated on a flexible poly(ether sulfone) (PES) substrate with inkjet-printed Ag electrode as an anode. Active layer of poly(3-hexylthiophene-2,5-diyl) (P3HT) layer was spin-coated on the Ag anode and then Al cathode was evaporated on the P3HT layer. The rectifying characteristics of P3HT diodes with different area sizes were compared, and their frequency response was analyzed for the sinusoidal input of different frequencies. The diode with smaller area exhibited higher breakdown voltage and operating frequency: The diode with a small area of 0.05 mm2 showed a 3 dB point at 1.8 MHz.

article i nfo Available online 15 July 2009 We fabricated poly(3-hexylthiophene) (P3HT) rectifiers with the 3-dB frequency higher than 2 MHz and analyzed their frequency characteristics using an impedance spectroscopy as well as current density-voltage (J-V) measurement. The J-V characteristics showed a typical diode behavior with good rectification ratio (~5 × 10 4 ). We extracted modeling parameters of the equivalent circuit and analyzed the interface and bulk characteristics of the P3HT diode from the impedance plot. The P3HT/Al interface layer shows highest RC constant. The diode with thin P3HT film exhibits lower RC constant at the P3HT/Al interface compared to thick P3HT films and therefore it shows better frequency response. The diode frequency response is analyzed using the P3HT mobility estimated by fitting the J-V characteristics with the space-charge-limited current (SCLC) formula. This mobility is similar to the mobility measured by the time-of-flight photoconductivity technique.

The potential application of molecular organic semiconductor needs the control adjustment of conductivity. The hole transport materials (HTL)a-NPD (N,N 0 -di(1-naphthyl)-N,N 0 -diphenylbenzidin) has been doped with metal oxide (molybdenum oxide) for the study of transport phenomena. Impedance spectroscopic measurements were performed with the applied external electric filed. The activation energy calculated (0.55, 0.48 and 0.50 eV) decreases with doping of metal oxide. There is a clear indication of space charge limited (SCL) conduction in the doped and undoped thin films. The cole–cole plot indicates the device can be represented by a parallel resistance and capacitance network in series with a series resistance (of 70 X). At high frequency; the conduction follows the universal power law for both doped–undoped a-NPD with MoO3 and the onset frequency increases with increasing bias voltages. The conduction mechanism can be explained by classical hopping barriers (CHB) mechanism for the system.

The e ect of a bu er layer on organic bulk hetrojunction solar cells of poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C61 butyric acid methyl ester fullerene derivative (PCBM) has been studied using impedance spectroscopy in the frequency range between 100 Hz and 1 MHz. The bu er layer interfaces with a metallic contact and with the organic bulk materials in uence the e ciency and the stability of devices. Thermal annealing of the devices improves the interface with the bu er layer, thereby lowering the majority and the minority carrier injection voltage. The photocurrent density-voltage (J-V) characteristics show that the ll factor of the device with a molybdenum-oxide (MoO3) bu er layer is higher than that of the device with a poly (3, 4ethylenedioxy-thiophene):polystyrenesulfonate (PEDOT:PSS) bu er layer. The equivalent circuit analysis for the PEDOT:PSS and the MoO3 bu er-layer devices shows that the device's capacitance and resistance for MoO3 is lower than that for PEDOT:PSS under illumination. The e ciency of the thermally-annealed PEDOT:PSS and MoO3 bu er-layer devices are 2.95 and 3.44 %, respectively. The lower e ciency of the PEDOT:PSS bu er-layer devices can be attributed to the formation of a thin insulator layer at the PEDOT:PSS/P3HT:PCBM interface under illumination.

We studied the e ect of post-annealing treatment on the photovoltaic (PV) properties of organic solar cells based on copper phthalocyanine (CuPc)/fullerene (C60) heterojunctions. In the device structure of ITO/CuPc (30 nm)/C60(40 nm)/BCP(10 nm)/LiF(0.5 nm)/Al, where BCP is 2,9-dimethyl-4,7-diphenyl-phenanthroline acting as an exciton blocking layer, a maximum power conversion e ciency ( p) of about 1 % under an AM 1.5 solar illumination intensity of 100 mW/cm2 was obtained at room temperature. By measuring the PV characteristics for the devices annealed at various temperatures for 30 minutes, we found that the short-circuit current and e ciency increased with increasing annealing temperature up to 100 C ( p 1:3 %) and then decreased at higher temperatures. We analyzed the e ect of thermal annealing on the improved device performance by measuring the optical absorption spectra and the X-ray di raction patterns of the CuPc/C60 lms.

Recent developments in monolayer graphene production allow its use as the active layer in field-effect transistor technology. Favorable electrical characteristics of monolayer graphene include high mobility, operating frequency, and good stability. These characteristics are governed by such key transport physical phenomena as electron-hole transport symmetry, Dirac point voltage, and charged impurity effects. Doping of graphene occurs during device fabrication, and is largely due to charged impurities located at or near the graphene/substrate interface. These impurities cause scattering of charge carriers, which lowers mobility. Such scattering is detrimental to graphene transistor performance, but our group has shown that coating with fluoropolymer thin films or exposure to polar organic vapors can restore favorable electrical characteristics to monolayer graphene. By partially neutralizing charged impurities and defects, we can improve the mobility by approximately a factor of 2, change the Dirac voltage by fairly large amounts, and reduce the residual carrier density significantly. We hypothesize that this phenomena results from screening of charged impurities by the polar molecules. To better understand such screening interactions, we performed computational chemistry experiments to observe interactions between polar organic molecules and monolayer graphene. The molecules interacted more strongly with defective graphene than with pristine graphene, and the electronic environment of graphene was altered. These computational observations correlate well with our experimental results to support our hypothesis that polar molecules can act to screen charged impurities on or near monolayer graphene. Such screening favorably mitigates charge scattering, improving graphene transistor performance.

Charge transport in polymer field-effect transistors is hugely affected by the polarization effects, which can be originated from polar molecules in the gate dielectric and ambient air. In this letter, we investigate the polarization induced trapping enhancement by dipoles in the gate dielectric layer and ambient air at the same time through the experiment with varying conditions of surface dielectric and polar analytes in the atmosphere. We demonstrate the result from diketopyrrolopyrrole based co-polymer transistors with high mobility. Polarization effects from dipoles in the atmosphere affect mostly the shallower trap states and are relatively less severe when the interface of the gate dielectric is very polar.

Few-layer black phosphorus (BP), also known as phosphorene, is poised to be the most attractive graphene analogue owing to its high mobility approaching that of graphene, and its thickness- tunable band gap that can be as large as that of molybdenum disulfide. In essence, phosphorene represents the much sought after high-mobility, large direct band gap two-dimensional layered crystal that is ideal for optoelectronics and flexible devices. However, its instability in air is of paramount concern for practical applications. Here, we demonstrate air-stable BP devices with dielectric and hydrophobic encapsulation. Microscopy, spectroscopy, and transport techniques were employed to elucidate the aging mechanism, which can initiate from the BP surface for bare samples, or edges for samples with thin dielectric coating highlighting the ineffectiveness of conventional scaled dielectrics. Our pioneering months-long studies indicate that a double layer of Al2O3 and hydrophobic fluoropolymer affords BP devices and transistors with indefinite air-stability for the first time, overcoming a critical material challenge for applied research and development., Comment: 22 pages, 4 figures

Endurable water-repellent coated layers have been formed on safety glasses for automobiles via a sol-gel based spray coating process. Coated films are composed of a silica underlayer (∼800 A) and a fluorocarbon layer in which the formed silica shows a definite surface roughness and acts as the enhancement factor for chemical and mechanical durability. Durability is a function of the degree of surface roughness, structural fineness and homogeneity. Dual stage aging in silica sol controls a wide range of surface roughness. Water-repellency is degraded gradually by a combination of sunlight (ultraviolet), water, and abrasion. Spray coating on large size and curved safety glasses was successfully carried out.

We report on the effects of mechanical distortion and gate insulator-semiconductor interface modification on the electronic transport characteristics of inkjet printed short channel length single walled carbon nanotube (SWCNT) transistors with Al2O3 top gate insulators. In these transistors, which are typically ambipolar, the average nanotube length is greater than the source-drain (S/D) spacing resulting in individual SWCNTs spanning the entire channel length. Mechanical distortion of the nanotubes due to bending near source and drain contacts when they are not recessed is found to suppress electron transport and transform the ambipolar transistors into p-type devices. Inclusion of printed interfacial polymer layers such as poly(vinylidene fluoride-trifluoroethylene) (PVDF-TrFE) between the SWCNTs and Al2O3 also results in p-type doping and reductions in electron transport. We discuss mechanisms responsible for these effects.

We report the improvement of the electrical performance of field effect transistors (FETs) fabricated on monolayer chemical vapor deposited (CVD) MoS2, by applying an interacting fluoropolymer capping layer (Teflon-AF). The electrical characterizations of more than 60 FETs, after applying Teflon-AF cap, show significant improvement of the device properties and reduced device to device variation. The improvement includes: 50% reduction of the average gate hysteresis, 30% reduction of the subthreshold swing and about an order of magnitude increase of the current on-off ratio. These favorable changes in device performance are attributed to the reduced exposure of MoS2 channels to the adsorbates in the ambient which can be explained by the polar nature of Teflon-AF cap. A positive shift in the threshold voltage of all the measured FETs is observed, which translates to the more desirable enhancement mode transistor characteristics.

Homosexual adolescents may face significant health disparities. We examined health-risk behaviors and health cognition related to homosexual behavior in a representative sample of adolescents.Data were obtained from 129,900 adolescents between 2008 and 2012 over 5 cycles of the Korean Youth Risk Behavior Survey, a national survey of students in grades 7 to 12. Various health-risk behaviors and aspects of health cognition were compared between homosexual and heterosexual adolescents and analyzed with multiple logistic regression models.Compared with heterosexual adolescents (n = 127,594), homosexual adolescents (n = 2306) were more likely to engage in various health-risk behaviors and to have poor health cognition. In multiple logistic regression analysis, not living with parents, alcohol experience (adjusted odds ratio, 1.50; 95% confidence interval, 1.26-1.78 for males and 1.66; 1.33-2.07 for females), smoking experience (1.80; 1.54-2.10 for males and 3.15; 2.61-3.79 for females), and drug experience (3.65; 2.81-4.80 for males and 3.23; 2.35-4.46 for females) were associated with homosexual behavior. Homosexual adolescents were more likely to use adult internet content (2.82; 2.27-3.50 for males and 7.42; 4.19-13.15 for females), and to be depressed (1.21; 1.03-1.43 for males and 1.32; 1.06-1.64 for females). In addition, suicide ideation (1.51; 1.26-1.81 for males and 1.47; 1.16-1.86 for females) and attempts (1.67; 1.37-2.05 for males and 1.65; 1.34-2.03 for females) were significantly more prevalent among homosexual adolescents.Homosexual adolescents report disparities in various aspects of health-risk behavior and health cognition, including use of multiple substances, adult internet content and inappropriate weight loss methods, suicide ideation and attempts, and depressive mood. These factors should be addressed relevantly to develop specific interventions regarding sexual minorities.

목적: 국내와 같이 결핵의 유병률이 높은 지역에서 결핵을 정확하게 진단하는 것은 중요하다. 본 예비 연구는 국내의 소아청소년에서 결핵진단 시 TST 및 2가지 IGRA 검사법 (QFT-G 및 T-SPOT.TB) 간의 일치도를 알아보고자 하였다. 방법: 2014년 1월부터 2015년 4월까지 잠복결핵감염 또는 결핵질환의 진단을 위해 서울아산병원을 방문한 20세 이하 환자 중, TST, T-SPOT.TB 및 QFT-G 검사 중 최소 2가지 이상의 검사를 동시에 시행한 경우를 연구에 포함하였다. 이들의 의무기록을 후향적으로 분석하여 각 검사 간의 일치도를 평가하였다. 결과: 연구에 포함된 총 20명의 연령의 중앙값은 13.3세(범위: 3.8-18.1세)이었고, 이 중 11명은 면역저하와 관련된 기저질환이 있었다. T-SPOT.TB와 QFT-G 결과의 일치도는 90%였으며, TST와 TSPOT.TB의 일치도는 50%, TST와 QFT-G의 일치도는 42.9%였다. T-SPOT.TB, QFT-G 및 TST의 결핵질환에 대한 특이도는 93.3%, 86.7% 및 58.3%였다. 결론: T-SPOT.TB과 QFT-G 간의 일치도는 높으나 TST와 T-SPOT.TB 또는 QFT-G 간의 일치도는 낮았다. 추후 국내 소아청소년의 정확한 결핵의 진단을 위한 각 검사들의 일치도 및 진단적 유용성에 대한 추가적인 연구가 필요하다.

최근 전세계적으로 지역사회 기원 메티실린내성 황색포도알균(CA-MRSA)에 의한 피부연부조직 감염증이 증가하고 있다. 16개월의 한국 여아가 생후 6개월부터 시작된 반복되는 피부연부조직 감염증을 주소로 내원하였다. 환아의 가족들도 환아와 비슷한 시기에 피부연부조직 감염증의 병력이 있었다. 환아의 혈중 면역글로불린 및 NBT 검사는 정상이었고, 피부 병변 외에는 가족 모두 건강하였다. 환아의 감염증 부위의 고름 배양 및 비강 내 보균 검사시 모두 PVL genes을 생성하는 CA-MRSA ST714 SCCmec type IV가 확인되었고, 이는 ST30의 single locus variant로서 국내에서는 보고된 적이 없는 MRSA의 유전형이다. 환아와 함께, 환아의 균주와 동일 항생제 감수성 양상을 보이는 MRSA 보균자인 환아부에게 재발 방지를 위해서 비강내 mupirocin 5일 요법을 시행하였고 이후 10개월간 추가적인 재발은 없었다.

We studied the effect of the buffer layer (molybdenum-oxide (MoO3)) thickness on the performance of organic solar cell based on blends of poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C61 butyric acid methyl ester fullerene derivative (PCBM). The thickness of MoO3 was varied from 1 nm to 30 nm for optimization of device performance. The photocurrent-voltage and impedance spectroscopy were measured under dark and AM1.5G solar simulated illumination of 100 mW/cm2 for exploring the role of the buffer layer thickness on carrier collection at an anode. The MoO3 thickness of the optimized device (efficiency approximately 3.7%) was found to be in the range of 5 approximately 10 nm. The short-circuit current and the shunt resistance decrease gradually for thicker MoO3 layer over 5 nm. The device can be modeled as the combination of three RC parallel circuits (each one for the active layer, buffer layer and interface between the buffer layer and the active layer) in series with contact resistance (Rs approximately 60 ohm).

In this presentation we will describe device designs, modeling, and experimental results with several new diketopyrrolopyrrole DPP-based polymers and specifically discuss techniques to keep the operating voltage low (< 10 V) in small channel length (< 5 mm) devices. We have been able to obtain mobility values of ~4 cm2/V-s with some of the materials in such devices at low operating voltages for channel lengths of 4 mm in air. These devices possess very high temperature field-induced conductivity of any polymer FET and which exceeds that of most organic single crystal FETs reported so far. Our best devices designs possess a bilayer gate insulator which includes a thin interfacial low- dielectric constant insulator. We will demonstrate that the mobility improvement arises due to the suppression of the formation of Fröhlich polarons, which tend to reduce mobility when polar media such as high-k dielectrics are used with polymer semiconductors. We will also discuss charge transport in such polymers transistors both above and below the threshold voltage.

목적: 국내 소아 그람음성균혈증에서 항생제 내성변화 및 항생제 사용량과의 관계를 분석하였다. 방법: 최근 10년간 18세 이하 입원 환자의 혈액에서 분리된 그람음성균의 항생제 내성률 변화 및 항생제 사용량과의 관계를 분석하였다. 결과: 폐렴막대균, 대장균, 녹농균, 아시네토박터 바우마니의 분리율은 연간 혈액배양 1,000건당 각각 4.6례, 3.5례, 3.4례 및 2.2례였다. 폐렴막대균에서 광범위 세팔로스포린에 대한 내성변화는 없었으나 2010년부터 카바페넴 내성 폐렴막대균이 동정된 후 점차 빈도가 증가하였다. 대장균의 광범위 세팔로스포린 내성이 10%에서 50%로 아시네토박터 바우마니의 카바페넴 내성이 11%에서 71%로 크게 증가하였다(P for trend

We report a more accurate method to determine the density of trap states in a polymer field-effect transistor. In the approach, we describe in this letter, we take into consideration the sub-threshold behavior in the calculation of the density of trap states. This is very important since the sub-threshold regime of operation extends to fairly large gate voltages in these disordered semiconductor based transistors. We employ the sub-threshold drift-limited mobility model (for sub-threshold response) and the conventional linear mobility model for above threshold response. The combined use of these two models allows us to extract the density of states from charge transport data much more accurately. We demonstrate our approach by analyzing data from diketopyrrolopyrrole based co-polymer transistors with high mobility. This approach will also work well for other disordered semiconductors in which sub-threshold conduction is important.