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Reliable estimation of organic matter characteristics is essential in source and reservoir rocks evaluation. Their measurement is generally based on well logging and experiments after core sampling. In this study, we present a different approach from these methods to evaluate the characteristics of organic matter, which is based on the numerical simulations in combination with machine learning technologies. Formation heating processes of organic-rich shales and in-situ pyrolysis of kerogen are numerically simulated, where the time-series data of heater temperature are monitored. Here, we consider the whole organic matter composed with kerogen. The monitored heater temperature data are used as an input of inverse modeling by Artificial Neural Network (ANN) and Support Vector Machines (SVM) to figure out the characteristics of kerogen. Heater temperature acts as an indicator of type and maturity of kerogen, since it is affected by the bulk thermal conductivity of formation, which is a function of dynamically changing rock-and-pore composition by kerogen decomposition. We simulate the processes of electrical heating of 300 different formations, containing either one of Type 1, 2, or 3 kerogen with various amounts and activation energies. ANN method is employed to generate a data-driven model to estimate the unknown kerogen content and activation energy using heater temperature as an input data. SVM method, which categorizes dataset into the multiple classes by using hyperplanes, is applied to classify the dataset of heater temperature into different types of kerogens. Developed ANN and SVM models show great performances in the inversion and classification. The suggested characterization method provides a simple tool of estimating reactivity and type of kerogens. It will be used as a proxy for the inverse modeling of geochemical characterization of organic matter coupled with forward numerical simulations, by reducing the number of simulation runs required in the traditional inverse modeling.

The association between spontaneous abortion (SA) and occupational characteristics among working women is not well-studied. This study aimed to assess the risk of SA and occupational factors such as occupational classification, working hours, and work schedules among working Korean women aged > 19 years. In this cross-sectional study, 4078 working women were identified from among 25,534 workers in the Korea National Health and Nutrition Examination Surveys V (2010–2012) database, to obtain data on SA history and the number of SAs. Odds ratios (ORs) and 95% confidence intervals (CIs) for SA were calculated using multiple logistic regression models after adjusting for age, education, household income, cigarette smoking, alcohol consumption, and obesity status. The weighted prevalence for the number of SAs was calculated according to occupational characteristics to demonstrate the SA status among working Korean women. SA occurrence was reported in 5.7% of the study participants. The ORs (95% CIs) for SA were significantly higher in pink-, green-, and blue-collared workers than in white-collared workers. Regarding weekly working hours, compared with ≤50 h spent working, the ORs (95% CIs) for 51–60, 61–70, and > 70 h per week were 1.26 (0.87–1.84), 1.63 (1.04–2.56), and 1.73 (1.10–2.70), respectively. A significantly higher weighted prevalence of repeat SAs was observed in pink- and green-collared workers and in those who worked long hours. We found a significant association between SA, repeat SA, and occupational characteristics among working Korean women.

Background The aim of this study was to assess the consistency between preoperative ultrasonographic and intraoperative measurements of the ulnar nerve in patients with cubital tunnel syndrome. Methods Twenty-six cases who underwent anterior transposition of the ulnar nerve for cubital tunnel syndrome were enrolled prospectively. On preoperative ultrasonography, largest cross-sectional diameters of the ulnar nerve were measured at the level of medial epicondyle (ME) and 3 cm proximal (PME) and distal (DME) to the ME on the transverse scan by a single experienced radiologist. Intraoperative direct measurements of the largest diameter at the same locations were performed by a single surgeon without knowledge of the preoperative values. The consistency between ultrasonographic and intraoperative values including the largest diameter and swelling ratio were assessed. Results Significant differences between ultrasonographic and intraoperative values of the largest diameter were found at all levels. The mean difference was 1.29 mm for PME, 1.38 mm for ME, and 1.12 mm for DME. The mean ME-PME swelling ratio for ultrasonographic and intraoperative measurements was 1.50 and 1.39, respectively, showing significant difference. The mean ME-DME swelling ratio for ultrasonographic and intraoperative measurements was 1.53 and 1.43, respectively, showing no significant difference. Conclusions Ultrasonographically measured largest diameters of the ulnar nerve at any levels were smaller than the real values determined intraoperatively. The ME-DME swelling ratio of the ulnar nerve measured by ultrasonography was consistent with the intraoperative measurement.

Magnetization reversal in a GaMnAs trilayer system consisting of two GaMnAs layers separated by a Be-doped GaAs spacer was investigated by magnetotransport measurements. The rotation of magnetization in the two GaMnAs layers is observed as two abrupt independent transitions in planar Hall resistance (PHR). Interestingly, one GaMnAs layer manifests a positive change in PHR, while the other layer shows a negative change for the same rotation of magnetization. Such opposite behavior of the two layers indicates that anisotropic magnetoresistance (AMR) has opposite signs in the two GaMnAs layers. Owing to this opposite behavior of AMR, we are able to identify the sequence of magnetic alignments in the two GaMnAs layers during magnetization reversal. The PHR signal can then be decomposed into two independent contributions, which reveal that the magnetic anisotropy of the GaMnAs layer with negative AMR is predominantly cubic, while it is predominantly uniaxial in the layer with positive AMR. This investigation suggests the ability of engineering the sign of AMR in GaMnAs multilayers, thus making it possible to obtain structures with multi-valued PHR, that can be used as multinary magnetic memory devices.

Allogenous bone chips and hydroxyapatite (HA) chips have been known as good options for filling an inevitable void after open wedge high tibial osteotomy (OWHTO). However, there are concerns regarding bone healing after the use of these grafts. The purpose of this study was to compare the bone healing represented by the osteoconductivity and absorbability between allogenous bone chips and HA chips in OWHTO. The outcomes of bone healing of 53 patients who received an allogenous bone chip graft and 41 patients who received an HA chip graft were retrospectively evaluated, and the results were compared between the two groups. Osteoconductivity and absorbability were serially evaluated for the assessment of bone healing at 6 weeks, 3 months, 6 months, and 1 year postoperatively. The osteoconductivity of the allogenous bone chips was greater than that of the HA chips at 6 weeks postoperatively (p

Background The purpose was to compare the efficacy between tenofovir disoproxil fumarate (TDF) and lamivudine (LMV) in children with nucleos(t)ide-naive chronic hepatitis B (CHB) infection. Patients with CHB were treated with TDF in the immune-reactive phase and compared with a historical control group of patients treated with LMV before the TDF era. Methods Hepatitis B virus (HBV) DNA titer decrements (> 3 log10 IU/mL) were monitored after treatment initiation. The treatment duration for HBV DNA clearance (< 357 IU/mL) and complete response (HBeAg loss and HBV DNA clearance) were analyzed. The follow-up period was 96 weeks. Results Sixteen patients were treated with TDF and compared with a historical control group of 24 patients treated with LMV. HBV DNA decrement (> 3 log10 IU/mL) was achieved in 100% (16/16) of the TDF group but in only 62.5% (15/24) of the LMV group (P = 0.005) at 48 weeks. The HBV DNA clearance (< 357 IU/mL) in the TDF and LMV groups was, respectively, as follows: 62.5% (10/16) and 25.0% (6/24) at 12 weeks (P = 0.018), 81.3% (13/16) and 37.5% (9/24) at 24 weeks (P = 0.006), 93.8% (15/16) and 50.0% (12/24) at 48 weeks (P = 0.004), and 100% (16/16) and 54.2% (13/24) at 96 weeks (P = 0.001). Complete response occurred in 41.7% (5/12) of HBeAg-positive patients in the TDF group and 28.6% (6/21) of the LMV group at 96 weeks (P = 0.443). Conclusion TDF monotherapy for 96 weeks produced a significantly more effective virologic response than LMV monotherapy in children with nucleos(t)ide-naive CHB., Graphical Abstract

summary Purpose: The purpose of this study was to investigate the health behaviors and risk factors for selfreported depression in Korean working women. Methods: This study adopted a secondary analysis from the fifth Korean National Health and Nutrition Examination Survey (KNHANES-V) for the Health Examination Survey and Health Behavior Survey, using stratified, multi-stage, cluster-sampling design to obtain a nationally representative sample. Data were gathered on extensive information including sociodemographic, occupational characteristics, health behaviors and depression. Multiple logistic regression analysis was employed to compute the odds ratio (OR) between health behaviors and depression to identify the health behaviors and the risk factors for depression with adjustment for the complex sample design of the survey. Results: The prevalence rate of depression was 15.5% among working women. Depression was more common in older female workers and in those with part-time job. Current smokers were significantly more likely to be depression-positive. In a multiple logistic regression analysis, significant variables of depression were marital status (OR ¼ 2.02; 95% CI [1.05, 3.89]), smoking status (OR ¼ 1.55; 95% CI [1.01, 2.38]), stress (OR ¼ 0.20; 95% CI [0.15, 0.26]), employment condition (OR ¼ 1.77; 95% CI [1.34, 2.33]) and health status (OR ¼ 2.10; 95% CI [1.53, 2.87]). Conclusions: Based on the study, factors leading to depression were marital status, current smoking, stress, employment condition and self-reported health status. Further studies are expected to unravel the characteristics of stress. Health care providers for women need to evaluate underreported depression and change their associated health behaviors. Also it is necessary to establish preventive strategies for female workers to control the negative effect of depression in the workplace.

Atypical femoral fractures are stress or insufficient fractures induced by low energy trauma or no trauma and have specific X-ray findings. Although the American Society for Bone and Mineral Research has excluded periprosthetic fractures from the definition of an atypical femoral fracture in 2013, this is still a matter of controversy because some authors report periprosthetic fractures showing specific features of atypical fractures around a well-fixed femoral stem. We report 3 cases of periprosthetic femur fractures that had specific radiographic features of atypical femoral fractures in patients with a history of prolonged bisphosphonate use; we also review relevant literature.

Here we report the superiority of WO3 thin films prepared by successive dip coating in electrochromic devices. Dip coatings were done on transparent conducting oxide substrates in the WO3 precursor solution a number of times without drying in between the coating steps. This process enabled the fabrication of WO3 films with optimum thickness and large roughness, which led to enhanced performance when they were employed as the electrode in electrochromic devices. We made a further observation by applying these electrodes in photoelectrochromic devices and verified the excellent properties of the successively dip-coated WO3 films.

Regardless of the method of treatment, as many as 5% of all pelvic fractures result in malunion or nonunion of the pelvis. However, there is not much information in the literature on the management of these late complications. Because they cause disabling symptoms and socioeconomic problems, some patients with malunion or nonunion of pelvic fractures need to undergo surgery. We report our experience with satisfactory results of surgery for pelvic malunion and nonunion in four patients. The key to successful reconstruction is thorough preoperative planning and methodical surgical intervention.

This study was conducted to analyze the relationship among climatic factors and radial growth of Pinus koraiensis in South Korea. To determine climate-growth relationships, cluster analysis was applied to group climatically similar surveyed regions, and dendroclimatological model was developed to predict radial growth for each climate group under the RCP 4.5 and RCP 8.5 scenarios for greenhouse gases. The dendroclimatological models were developed through climatic variables and standardized residual chronology for each climatic cluster of P. koraiensis. 2 to 4 climatic variables were used in the models (R 2 values between 0.35~0.49). For each of the climatic clusters for Pinus koraiensis, the growth simulations obtained from two RCP climate-change scenarios were used for growth prediction. The radial growth of the Clusters 2 and 3, which grow at high elevation, tend to increase. In contrast, Cluster 1, which grows at low elevation, tends to decrease with a large difference. Thus, the growth of Pinus koraiensis, which is a boreal species, could increase along with increasing temperature up to a certain point.

The encapsulation of silicon in hollow carbonaceous shells (Si@C) is known to be a successful solution for silicon anodes in Li-ion batteries, resulting in many efforts to manipulate the structural properties of carbonaceous materials to improve their electrochemical performance. In this regard, we demonstrate in this work how both the shell thickness and pore size of nanoporous carbonaceous materials containing silicon anodes influence the electrochemical performance. Structurally well-defined Si@C materials with varying carbon-shell thicknesses and pore sizes were synthesized by a nanocasting method that manipulated the carbon shell and by a subsequent magnesiothermic reduction that converted the amorphous silica cores into silicon nanocrystals. When these materials were employed as anodes, it was verified that two opposite effects occur with respect to the thickness of carbon shell: The weight ratio of silicon and the electrical conductivity are simultaneously affected, so that the best electrochemical...

Ion transport is an important issue in electrochemical-based energy conversion and storage devices. Ion transport at the interface of the electrode and electrolyte is critical for performance. However, there is little understanding of the interface phenomena based on ion transport properties. Here, the proton transport behavior in a Nafion membrane (electrolyte) and that of an ionomer in the catalyst layer (electrode/electrolyte interface) was investigated simultaneously by electrochemical impedance spectroscopy. Our study indicates that the proton transport behavior in the catalyst layer is different from that in membrane. To elucidate the interface phenomena, we analyzed the Nafion electrolyte and proton behavior by molecular dynamics (MD). On the basis of the MD results, we modified the catalyst with a hybrid of inorganic Pt catalyst and organic 3-mercaptopropionic acid to promote a positive interfacial reaction between the electrolyte and electrode, which resulted in improved proton transport and perf...

The purpose of this study was to evaluate mixed model of dbh-height relation containing random effect. Data were obtained from a survey site for Quercus variabilis in Gangwon region and remeasured the same site after three years. The mixed model were used to fixed effect in the dbh-height relation for Quercus variabilis, with random effect representing correlation of survey period were obtained. To verify the evaluation of the model for random effect, the akaike information criterion (abbreviated as, AIC) was used to calculate the variance-covariance matrix, and residual of repeated data. The estimated variance-covariance matrix, and residual were -0.0291, 0.1007, respectively. The model with random effect (AIC

In lithium-ion batteries, enhancing the diffusion of lithium ions through the electrolyte is one of the most important factors in maximizing the utilization of active material at high current densities. In this regard significant efforts to use mesoporous material as an active material have been attempted. However, it has not been well understood how pore parameters, such as pore size, particle size, and tortuosity of the mesoporous materials, affect the electrochemical performance. In this study, three-dimensionally ordered mesoporous titania with different pore and particle sizes synthesized by a hard template method using a size-tunable silica particle and a commercial titania particle with random mesopores were used to investigate the effects of these parameters on the electrochemical performance. Furthermore, a mathematical model, frequently used for a porous catalytic systems, was employed to rationalize the experimental results by introducing the Thiele modulus parameter. The model derived from com...

It is critical to maintain stability of hydrate bearing sediments for safe and successful drilling. Changes of pressure and temperature distributions can trigger formation instability due to hydrate dissociation. In order to prevent such problems, it is necessary to model the behavior of hydrate bearing sediments. In this study, a real-time model of drilling through hydrate bearing sediments has been developed. The developed model can predict distributions of in-situ temperature, pressure, hydrate saturation, and gas saturation while drilling. Several simulations are conducted in the environment of gas hydrate formation in Ulleung Basin, the East Sea of Korea under various drilling and formation conditions. Guidelines for the safe drilling ranges can be provided by analyzing the simulation results.

We report on the facile synthesis of porous silicon structure via magnesiothermic reduction followed by coating of the surface with TiSi2. These modifications not only showed significant promise in overcoming the drastic volume change during charge and discharge cycles but also in improving the relatively low conductivity of silicon. The synthesized porous structure with a highly electrically conductive coating layer significantly enhanced the electrochemical performance in terms of cyclic stability and rate capability. The TiSi2 coating layer, which has good electrical conductivity and physical strength, enhances the conductivity and maintains the Si structure during cycling. This combination of porous structure via magnesiothermic reduction and highly conductive TiSi2 coating provides a synergistic effect, which can be seen in the improvements in electrochemical performance. This synthesis demonstrates a promising method for producing high capacity anode materials for next generation LIBs.

Purpose To evaluate the hemostatic effect of intraarticular injection of a thrombin-based hemostatic agent in total knee arthroplasty (TKA). Materials and methods We performed a prospective randomized controlled trial on the use of a thrombin-based hemostatic agent in patients undergoing unilateral TKA. A total of 100 TKA patients were enrolled, with 50 patients randomized into the study group and the other 50 patients into the controlled group. Drain output, hemoglobin level, total red blood cell loss for 24 hours after surgery, transfusion rates, and complications were assessed. Results Postoperative drain output was 525 mL in the study group and 667 mL in the control group (p=0.01). Nine patients in the study group and eighteen in the control group received blood transfusion (p=0.043). But, there was no significant difference between two groups in terms of hemoglobin level change and total red blood cell loss (p>0.05). Conclusions The thrombin-based hemostatic agent demonstrated efficacy in reducing drain output and blood transfusion rates. Thus, we believe the use of a thrombin-based hemostatic agent should be considered as an option in orthopedic surgery that involves massive bleeding.

Summary Although total hip arthroplasty (THA) is accepted as one of the most successful surgical procedures in orthopaedic surgery, periprosthetic joint infection after THA continues to be one of the most devastating complications. However, accurate preoperative identification of periprosthetic joint infection in patients presenting with joint pain or radiographic periprosthetic lucencies is often difficult, even after a comprehensive work-up. The purpose of this article is to review the diagnostic options available to improve the management and results of this potentially catastrophic complication.

The objective of this study was to analyze the prevalence and causes of early re-operation after hip replacement surgery using short bone-preserving stems in a large multicentre series. Specifically, we evaluated the clinical features of periprosthetic fractures occurring around short stems. A total of 897 patients (1089 hips) who underwent primary total hip arthroplasty or bipolar hemiarthroplasty from January 2011 to February 2015 using short bone-preserving femoral stems were recruited. Mean patient age was 57.4 years (range, 18–97 years), with a male ratio of 49.7% (541/1089). Re-operation for any reason within two years was used as an endpoint. The incidence and clinical characteristics of the periprosthetic femoral fractures were also recorded. Mean follow-up period was 5.1 years (range, 2–7.9 years). Early re-operation for any reason was identified in 16 (1.5%) of 1089 hips. The main reason for re-operation was periprosthetic femoral fracture, which accounted for eight (50%) of the 16 re-operations. The overall incidence of periprosthetic femoral fracture at two years was 1.1% (12/1089). According to the Vancouver classification, two fractures were AG type and the other ten were B1 type. Advanced age, higher American Society of Anesthesiologist grade, femur morphology of Dorr type C, and the use of a calcar-loading stem increased the risk for periprosthetic femoral fracture. Periprosthetic femoral fracture was the major reason for re-operation after hip replacement surgery using short bone-preserving stems accounting for 50% (8/16) of re-operations two years post-operatively, but did not seem to deteriorate survivorship of implanted prostheses.

Background Sleep disorders and depression/anxiety disorders are long-standing and significant problem for mental health. Also there are already known so many negative health effect of these disorders. But there were few studies to examine the association between activities outside work and forementioned disorders. So this study aimed the association of those things by using the Republic of Korean data. Methods Data from 32,232 wage workers were used in the 4th Korean Working Condition Survey. General and occupational characteristics, sleep disorders, depression/anxiety disorders and activities outside work are included in questionnaire. To find the relationship between activities outside work and sleep, depression/anxiety disorders, multivariate logistic regression analysis was used after adjusting for general and occupational characteristics. Results We observed that volunteer activities increased the odds ratio of both sleep disorders and depression/anxiety disorders(Odds ratio[OR] = 1.35, 95% confidence interval[CI]: 1.03–1.78 and OR = 1.54, 95% CI: 1.29–1.84, respectively). And self-development activities increase the odds ratio of sleep disorders(OR = 1.35, 95% CI: 1.17–1.57). Gardening activities lowered the odds ratio of depression/anxiety disorders(OR = 0.74, 95% CI: 0.59–0.94). Conclusion Some of activities outside work were related to sleep disorders and depression/anxiety disorders among Korean wage workers. Our results showed negative health effect of some kinds of activities outside work such as volunteering and self-devlopment compared to other studies that emphasized positive effect of those activities for health.

© 2017, © The Author(s) 2017. We investigate the productivity and product selectivity of diverse thermal in situ upgrading processes in oil shale reservoirs. In situ upgrading processes applying the ideas of Shell In situ Conversion Process, ExxonMobil Electrofrac, and Texas A&M Steamfrac are simulated by using sector models with the assumption of symmetric patterns. In-house fully functional simulator is used, which has been developed for the kerogen pyrolysis and hydrocarbon production. In the simulation cases, sensitivity analyses to the factors having major influence on the productivity and product selectivity are conducted. The effects of the temperature of vertical heaters, the spacing of hydraulic fractures, and the position of horizontal production wells are analyzed in the applied In situ Conversion Process, Electrofrac, and Steamfrac, respectively. In the applied In situ Conversion Process cases, hydrocarbon production increases with the increasing heater temperature. In the applied Electrofrac cases, hydrocarbon production increases with the increasing spacing of hydraulic fractures, even though longer time period for the process is needed. In the applied Steamfrac cases, the case of production well located at the same depth to the injection well shows the least hydrocarbon production. Among the processes, the applied In situ Conversion Process cases show the highest weight percentage of total hydrocarbon components in the produced fluid, and the applied Electrofrac cases follow it. The applied Steamfrac cases show far lower weight percentage of hydrocarbon production than the other methods. In terms of the mass ratio of produced hydrocarbon to decomposed kerogen, the applied Steamfrac cases show the largest value among the processes by aqueous phase sweeping liquid organic phase, but they also show the huge water oil mass ratio by the continuous injection of hot water. All the applied In situ Conversion Process cases and the Electrofrac case with the short spacing of hydraulic fractures show good heating efficiency by decomposing whole kerogen in the system.

Trabecular bone score (TBS) may detect subjects with a more degraded microarchitecture but whose bone mineral density (BMD) reflects normal or osteopenia. The purpose of this study was to evaluate whether age and body sizes were associated with the discordance between BMD and TBS. We analyzed BMD and TBS in 1505 Korean women over 40 yr of age who had no history of osteoporotic fractures or conditions that affect bone metabolism. We considered 3 groups to have TBS values that reflected a more degraded TBS than their BMD values: (1) normal BMD but partially degraded TBS, (2) normal BMD but degraded TBS, and (3) osteopenia but degraded TBS. We compared subjects in these 3 groups with other subjects in terms of age and body sizes, and used multivariable logistic regression to analyze the odds ratios (ORs) for the occurrence of a more degraded TBS than their BMD level using age and body mass index (BMI). One hundred sixty subjects (10.6%) were found to have a more degraded TBS than their BMD level; these subjects were older, heavier, and had higher BMIs than the other subjects. Age (OR: 1.038, 95% confidence interval: 1.020–1.057, p 0.001) and BMI (OR: 1.223, 95% confidence interval: 1.166–1.283, p 0.001) were statistically significant in the multivariable analysis for the occurrence of this feature. Women with a more degraded TBS than their BMD level are older and have higher BMIs than the other subjects. It may be helpful to consider the possibility of trabecular bone degradation when clinically evaluating fracture risk in patients who are older or who have high BMIs with normal BMD or osteopenia.

Summary Purpose Physical activity is important for postpartum women. The objective of this study was to evaluate bladder symptoms, fatigue, and physical activity according to time after birth and birth modes. Methods This was a cross-sectional study using web-based questionnaire or one-to-one contact. A total of 290 women after giving birth responded to self-administered questionnaires. Multivariate analysis of variance determined the differences in variables. Results Bladder symptoms were significantly different by time after birth and birth mode; they were the highest in the first week after birth and in Cesarean birth. Postpartum fatigue showed a significant tendency by birth mode, but not by time after birth. Physical activity was significantly different by birth mode. The lowest level of physical activity was found for women who gave Cesarean birth. Moderate physical activity was also significantly different by time after birth, but vigorous physical activity was not significantly different. Conclusion In conclusion, bladder symptoms and physical activity are different by time after birth and birth mode in postpartum women. The first week after giving birth is an important period for postpartum women whose bladder symptoms and physical activity should be of concern.

S INCE the concept of a supersonic-combustion ramjet, i.e. scramjet, was introduced, it has always been considered to be a candidate power plant for a hypersonic vehicle for use as a civil transport or a portion of a space launch system. The classical concept of a scramjet engine envisions it to use hydrogen as the fuel and to operate highly efficiently in Mach numbers of 6 and above [1–3], producing a large flight range as well as reaching the destination fast. In practice, many problems have been found with the hydrogenburning scramjet idea: to achieve high fuel efficiency, the combustor must operate at a high supersonic Mach number. Such a high combustor Mach number prevents fuel from mixing with air. The volume of the tank holding hydrogen becomes very large. The skin temperature becomes so high that no existingmaterial could sustain a cruising condition. Gaseous hydrocarbon fuels, such as ethylene or methane, have also been investigated [4,5]. These fuels need tanks that are much smaller than those needed for hydrogen. But these fuels must still be cryogenically stored. For this reason, kerosene has been studied extensively as an alternate fuel for the past several decades [6,7]. Kerosene is a liquid at room temperature and requires a much smaller tank volume than that required for hydrogen. Although ignition and flame holding become difficult for a liquid fuel, the problems are solved by applying advanced fuel atomizing techniques [7] or using additives [8]. Kerosene, as well as other hydrocarbon fuels, can be used for vehicles having a flight Mach number of only 3.5 to 5. Flying at such a relatively lowMach number, the combustor entranceMach number becomes low supersonic. At such a low supersonic Mach number, fuel–air mixing will improve greatly over a vehicle flying at Mach 6 or higher. Besides, the skin temperature becomes so much lower. Heat flux is proportional to the square of flight speed, and therefore there is a large difference between theMach 4 andMach 6 vehicles in the skin temperature. In this study, a kerosene-burning scramjet engine model is designed and tested to obtain an overall insight into such an engine. A blowdown, free-jet-type continuous facility is used. A scramjet engine, in an integrated form of an intake, isolator, and combustor, is used as the test model. Ignition and fuel atomization parameters as well as the fuel equivalence ratio and the geometry parameter such as combustor length are changed for respective experiments. Through this experiment, some aspects of the relationship between the scramjet engine configuration and the operational characteristics such as pressure rise, thermal choking, supersonic-to-subsonic transition, and intake unstarts are discovered.

우리나라의 중요한 조림 수종 중에서 낙엽송을 대상으로 하여, 간벌실시에 따른 물리·역학적 성질을 비교 평가함으로써 간벌 실시가 목재의 재질에 미치는 영향과 양질재 생산 및 목재의 효율적 이용을 위한 연구결과는 다음과 같다. 간벌정도에 따른 시료는 무간벌, 약도간벌, 강도간벌을 실시한 광릉시험림에서 벌채하여 사용하였다. 간벌 정도에 따른 평균 만재율은 무간벌 약도간벌 >강도간벌의 경향이었고 간벌 정도에 따른 평균 압축강도는 무간벌 > 약도간벌 >강도간벌의 경향이었다. 이러한 결과로 낙엽송은 간벌에 의하여 휨 및 종압축강도가 감소하는 경향이었다.

Nano-Si embedded Si7Ti4Ni4 is synthesized with the melt spinning method, which is facile, and applicable to mass-production. Si7Ti4Ni4, the buffer material, is electrochemically inactive toward lithium. Nevertheless, Si7Ti4Ni4 has good electrical conductivity, in the order of 105 S m−1, which is more conductive than amorphous carbon that is usually used as a coating material for active material. Furthermore, the surrounding grain boundaries of Si7Ti4Ni4 effectively relax volume expansion of Si. Therefore, it plays a critical role in maintaining the structure of electrode and the integrity of active materials. As a result, nano-Si embedded in Si7Ti4Ni4 shows outstanding cycle performance over 50 cycles at 400 mA g−1, and it maintains 86% of its specific capacity at 3200 mA g−1, compared with that of 400 mA g−1. This indicates that nano-Si embedded in Si7Ti4Ni4 can be a promising anode material for lithium ion batteries.

BACKGROUND Most breast cancer survivors experience psychological and spiritual distress, including depression, anxiety, perceived stress, and loss of meaningfulness in life. This distress can negatively impact physical health, quality of life, and quality of sleep. OBJECTIVE The aim of this study was to compare and examine the effectiveness of mind subtraction meditation (MSM) and a self-management education (SME) group on breast cancer survivors. METHODS A randomized controlled trial was conducted with South Korean female breast cancer survivors (stages I-III). Self-reported questionnaires were administered to both MSM group (n = 22) and SME group (n = 24) to measure psychological and spiritual well-being, as well as quality of sleep. RESULTS Compared with the SME group, the MSM group reported a significant decrease in depression (P = .034), anxiety (P = .036), and perceived stress (P = .009) and an increase in quality of life (P < .001), satisfaction with life (P < .001), posttraumatic growth (P = .007), and quality of sleep (P = .010). CONCLUSIONS Mind subtraction meditation may have positive therapeutic effects among breast cancer survivors. This meditation program may be useful to manage psychological and spiritual distress, as well as improve quality of life and sleep, in clinical settings among breast cancer survivors. IMPLICATIONS FOR PRACTICE This study demonstrated the clinical effectiveness and the feasibility of applying the MSM method to breast cancer survivors. The participants had a high attendance rate in the program, which speaks to the likelihood of the applicability of the meditation program on an outpatient basis.

b형 헤모필루스 인플루엔자균 예방접종이 시행된 이후 b형 헤모필루스 인플루엔자균에 의한 감염률은 급격히 감소하였으나, non-b형 헤모필루스 인플루엔자균에 의한 감염의 비율이 증가하는 추세이다. 대뇌 정맥동 혈전증은 드물지만 세균성 수막염의 합병증 중 하나로 발생할 수 있다. 대뇌 정맥동 혈전증이 동반된 f형 헤모필루스 인플루엔자균에 의한 뇌수막염 환자를 진단 및 치료하였기에 보고하는 바이다.

*GLP Center, Catholic University of Daegu, Keongsan 712-702, Korea. **Jeongseon Agricultural Extension Center, Jeongseon 233-852, Korea.***Department of Applied Plant Sciences, Kangwon National University, Chuncheon 200-701, Korea.****Department of Applied BioScience, Konkuk University, Seoul 143-701, Korea.*****Food Policy Cordination Division, Ministry of Korea Food & Drug Safety, Cheongwon 363-951, Korea.******Forest Practice Research Center, Korea Forest Reserach Institute, Pocheon 487-821, Korea.*******Department of Herbal Medicine Resource, Kangwon National University, Samcheok 245-905, Korea.ABSTRACT : Pharmacological studies and clinical practices have indicated that Radix Astragali, a dried root of Astragalusmembranaceus possesses a lot of biological activities, including antioxidant, hepatoprotective, anti-diabetic, tonic, diuretic,antimicrobial, antiviral, and immunological activities. These biological activities approved by the modern pharmacologicalstudies are mainly due to the constituents of Astragalus membranaceus including polysaccharides, saponins, flavonoids,amino acids, and trace elements. In resent, the main constituents in the root part showing a lot of biological activities hasbeen isolated also from the aboveground parts such as leaves and sprouts in our laboratory. However, the safety evaluationfor the aboveground parts of Astragalus membranaceus should be checked before expanding their application as one of food.In the study, a 90-day rat oral gavage study has been conducted with the extracts from Astragalus membranaceus-above-ground parts at doses of 1000, 3000, and 5000 ㎎/㎏/day. The following endpoints were evaluated: clinical observations, bodyweight, gross and microscopic pathology, clinical chemistry, and hematology. Based on the analysis of these endpoints, it wasestimated that NOEL (no observed effect level) for male rats and NOAEL (no observed adverse effect level) for female ratsare 5000 ㎎/㎏/day of the water-extracts from Astragalus membranaceus- aboveground parts. Key Words : Astragalus membranaceus, Aboveground Parts, NOAEL, Toxicity

Results: A significant increase in fatigue was observed in the high stress group related to job demand, organizational system, lack of reward, and occupational climate than in the low group (P < 0.001; P = 0.008; P = 0.045; P = 0.003, respectively). In a multiple regression analysis, fatigue was associated with job demand, insufficient job control, and occupational climate (P = 0.007; P = 0.024; P < 0.001, respectively). Fatigue was associated with work department, although a borderline statistical significance was seen (P = 0.005). Conclusion: To prevent fatigue in university hospital nurses, it is important to consider work department, job contents, and working environment related to job stress. Preventive strategies to lower fatigue will be needed under the consideration of job stress related to job demand, insufficient job control and occupational climate for university hospital nurses.

Purpose: To evaluate clinical results of two-stage revision using a modified articulating spacer for treatment of infected total knee arthroplasty (TKA). Materials and Methods: We retrospectively reviewed 20 cases treated by two-stage revision arthroplasty using a modified articulating spacer under the diagnosis of infected TKA from January 2006 to December 2011. The mean follow-up period was 22.3 months. The first operation consisted of debridement after removal of the prosthesis, reinsertion of the femoral component after autoclaving, and implantation of antibiotic-loaded cement with a new polyethylene in the proximal tibia. Results: The mean period between the primary TKA and the first stage operation was 39 months and between the first stage operation and the revision arthroplasty was 3.3 months. The average range of motion (ROM) increased from 69.8° preoperatively to 102.8° postoperatively (p

In this study, the effects of the diameter and quantity of fuel nozzles combined with various cavity-type flame holders for supersonic combustion were investigated empirically and numerically. Although increasing the quantity of fuel nozzles yields a greater fuel-to-air interface area, which results in a higher fuel–air mixing rate, smaller nozzle diameters yield a lower penetration depth, which results in a lower combustion performance at the top wall region. This study adopts the cavity shapes of fuel injectors from previous research studies to design new injector configurations with different sizes and quantities of fuel nozzles. The diameter and quantity of nozzles are determined to have the same equivalence ratio and momentum ratio as were used in previous research under a given fuel pressure. A comparison of results from the present tests with previous research shows that the plain cavity and zigzag cavity have distinct characteristics. Configurations using these cavity types were investigated via t...

Wellbore stability is one of critical issues in drilling operations in all types of environments. The wellbore stability in heat sensitive formations, such as through gas hydrates bearing formations, is largely dependent upon the flow of heated mud into these formations and their dissociation. The objective of this study is to analyze the thermal disturbance due to the flow of heated mud. A wellbore temperature simulator is developed and sensitivity analyses of drilling parameters are made to monitor the factors affecting thermal disturbance. It is found that due to an increase in well depth, the mud becomes hot enough and greatly disturbs the in-situ formations temperature of shallow formations. This formation thermal disturbance is critical, particularly in gas hydrate bearing formations and in the permafrost regions where formation heating can cause severe wellbore stability problems.

Solution processed hybrid silver nanowire (AgNW)-graphene nanoplatelets (GNP) films were prepared and the electrocatalytic activity for the cobalt redox electrolyte in dye-sensitized solar cells (DSSCs) was examined. Cyclic voltammograms and Tafel polarization measurements confirmed the superior electrocatalytic activity of AgNW-GNP electrode than that of standard Pt counter electrode (CE). Electrochemical impedance spectroscopic (EIS) study also revealed the lower charge transfer resistance (Rct) of AgNW-GNP compared to Pt based CE. However, the resistance of the electrolyte diffusion was higher for the AgNW-GNP based CE resulted from the porous structure of the hybrid CE. The photoconversion efficiencies of the DSSC prepared with AgNW-GNP based CE was found to be 2.44%, which was comparable to that of Pt based DSSC, 2.55%. This study proposed an alternative low-cost cathode material for the cobalt redox mediator based DSSCs.

Combustion tests were conducted for a hydrogen-fueled Mach 5 scramjet engine model using a blow-down facility. No fuel and two fuel flow rate cases were tested for two different model configurations. Time history of the wall static pressures inside the model and their time-averaged spatial distribution were used for the analysis of the flow and combustion characteristics. For shorter model, supersonic combustion was occurred for both of the fuel flow rate cases. For longer model, supersonic combustion was occurred for less fuel case, whereas thermal choking and subsonic combustion were occurred for more fuel case. Intake started even for this subsonic combustion case.

Background Frozen shoulder is a debilitating condition characterized by gradual loss of glenohumeral motion with chronic inflammation and capsular fibrosis. Yet its pathogenesis remains largely unknown. We hypothesized that the subacromial bursa may be responsible for the pathogenesis of frozen shoulder by producing inflammatory cytokines. Materials and methods We obtained joint capsules and subacromial bursae from 14 patients with idiopathic frozen shoulder and from 7 control subjects to determine the expression levels of interleukin (IL) 1α, IL-1β, IL-6, tumor necrosis factor α (TNF-α), cyclooxygenase (COX) 1, and COX-2 by real-time reverse transcriptase–polymerase chain reaction, immunohistochemistry, and enzyme-linked immunosorbent assay. Results IL-1α, IL-1β, TNF-α, COX-1, and COX-2 were expressed at significantly high levels in the joint capsules of the frozen shoulder group compared with those of the control group. Intriguingly, IL-1α, TNF-α, and COX-2 were also expressed at significantly high levels in the subacromial bursae of the frozen shoulder group compared with those of the control group. Immunohistochemical analysis showed increased expression of COX-2 in both the joint capsules and subacromial bursae of the frozen shoulder group. Conclusions These findings imply that elevated levels of inflammatory cytokines in the subacromial bursa may be associated with the pathogenesis of inflammation evolving into fibrosis.

O PERATION of a scramjet engine involves many gas dynamic and combustion phenomena. The components of a scramjet engine, such as the intake, isolator, fuel injector, and flame holder, interact with each other in a complicated manner and may result in successful engine operation or fall into intake unstart, misfire, blowout, or thermal choking. Much of the previous experimental research on scramjets focuses on a single component, and examples of experimental research on the integrated intake, isolator, and combustor are fewer.Moreover, much research uses impact facilities, i.e., shock tubes or shock tunnels, and sometimes they cannot represent real operational conditions of the scramjet engine. For an example, some research shows that the scramjet intake starts more easily in impact facilities than in continuous facilities [1]. In this study, the effect of the combustor configuration on the flow and combustion in a scramjet engine is explored experimentally. A blowdown freejet-type continuous facility is used.A scramjet engine, in an integrated form of an intake, isolator, and combustor, is used as the test model. Fuel injector, cavity flame holder, and combustor configurations are changed for respective experiments. Through this experiment, some aspects of the relationships between the scramjet engine injector, cavity, and combustor configuration and the operational characteristics such as intake starts and unstarts, supersonic combustion, and combustion-driven unstarts are brought to light.

We evaluated 162 hips with osteonecrosis of the femoral head that had undergone THA using highly cross-linked polyethylene liner after a minimum follow-up of 5 years. Neither femoral nor acetabular components displayed radiographic evidence of mechanical loosening or osteolysis, and no components had been revised at the latest follow-up. The mean rate of linear liner wear was 0.038 mm/year. Univariate regression analysis did not demonstrate that age, gender, weight, activity level or cup inclination had any influence on penetration. While the long term effects of altered mechanical properties of highly cross-linked PE remain unknown, the clinical and radiographic results at a minimum of 5 years are promising for this high-risk population.

Purpose To evaluate the clinical and radiological results of patients that underwent total knee arthroplasty (TKA) with a NexGen LPS-Flex implant using a Navigation system (Brain Lab). Materials and Methods Between January 2001 and December 2005, 55 knees in 46 patients which used the NexGen LPS-Flex implant with a Navigation system (Brain Lab) for primary TKA were clinically and radiologically evaluated after a minimum follow-up of 5 years. Evaluation included preoperative and postoperative range of motion (ROM), Knee Society Score (KSS), tibio-femoral angle and postoperative complications. Results Knee ROM was increased from 118.9° preoperatively to 126.9° at the last follow up. In addition, the preoperative flexion contracture improved from 6.5° to 1.8° postoperatively. The mean KSS and functional score were improved from 59.8 and 51.2 to postoperative scores of 86.4 and 85.2 respectively. The rate of appearance of radiolucency in X-ray was 21.8%. One case of superficial skin infection and one case of aseptic loosening were noted as complications but, did not require a revision surgery. Conclusions TKA with NexGen LPS-Flex implant using Navigation system (Brain Lab) showed satisfactory improvement in pain and function, but more long term follow up will be needed to complete verification.