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Damper is frequently used to suppress panel vibration and related vehicle interior noise. Unlike an unconstrained damper, a method to find material properties of a constrained damper is more complicated. This study presents a verified method for obtaining material properties of a constrained asymmetrical damper. The most important material parameters of this constrained damper are shear modulus, shear factor, and of course damping loss factor. The paper provides newly corrected equations to give proper numerical values of these parameters. The difference of natural frequencies between the test and the simulation using the estimated values is about 2 %, which shows that the estimation method is correctly presented. Important characteristics such as shear motion and wavelength of a composite beam constrained by a damper are also investigated. Finally, vibration response of a vehicle roof with a constrained damper is measured and is compared to the simulation. It is noticed that the correlation is much improved, comparing with the simulation based on old material properties.

Background: Recent studies have reported high rates of recurrence of shoulder instability in patients with glenoid bone defects greater than 20% after capsulolabral reconstruction. The purpose of the present study was to evaluate the failure rate of arthroscopic capsulolabral reconstruction for the treatment of anterior instability in the presence of glenoid bone deficits >20%. Methods: Retrospective analyses were conducted among cases with anterior shoulder instability and glenoid bone defects of >20% that were treated by arthroscopic capsulolabral reconstruction with a minimum 2-year follow-up (30 cases). We included the following variables: age, bone defect size, instability severity index score (ISIS), on-/off-track assessment, incidence recurrent instability, and return to sports. Results: The mean glenoid bone defect size was 25.8% ± 4.2% (range, 20.4%–37.2%), and 18 cases (60%) had defects of >25%. Bony Bankart lesions were identified in 11 cases (36.7%). Eleven cases (36.7%) had ISIS scores >6 points and 21 cases (70%) had off-track lesions. No cases of recurrent instability were identified over a mean follow-up of 39.9 months (range, 24–86 months), but a sense of subluxation was reported by three patients. Return to sports at the preinjury level was possible in 24 cases (80%), and the average satisfaction rating was 92%. Conclusions: Arthroscopic soft tissue reconstruction was successful for treating anterior shoulder instability among patients with glenoid bone defects >20%, even enabling return to sports. Future studies should focus on determining the range of bone defect sizes that can be successfully managed by soft tissue repair.

Synthetic natural gas (SNG) from syngas is considered a promising substitute for fossil fuels because of its environmental advantages; however, its heating value is below the standard heating value (especially in South Korea and Japan). In this study, bimetallic Co-Fe catalysts were developed for the production of C2-C4 hydrocarbons for usage as mixing gases to improve the heating value of SNG. The effect of the process conditions on the catalytic behavior was investigated. Catalyst 5Co-15Fe/γ-Al2O3 showed the best results with 91.2% CO conversion, 28.2% C2-C4 selectivity, and 0.98 paraffin ratio at H2/CO = 3.0 and 300 °C.

BACKGROUND A decreased acromiohumeral distance (AHD) is commonly detected in patients with massive rotator cuff tears (mRCTs). Most studies evaluating fixed humeral elevation have used preoperative or postoperative standardized radiography and not stress radiography. This study aimed to evaluate the predictive role of the preoperative AHD measured using stress radiography (AHD_stress) in rotator cuff healing and function after arthroscopic repair of mRCTs. METHODS The data of 113 patients who underwent arthroscopic repair of mRCTs were analyzed. Postoperative cuff integrity was evaluated using magnetic resonance imaging at 1 year, and shoulder function was evaluated at a mean of 34.9 ± 17.8 months (range, 24-92 months) postoperatively. Forty-seven patients showed healing failure. Propensity score matching (1-1) was performed between the healed group and healing failure group. Thirty-eight patients in each group were matched in the final analysis. The AHD and AHD_stress were defined as the shortest distances from the inferior acromion to the superior humerus on standard anteroposterior radiography and stress radiography (5.4-kg weight applied inferiorly in a neutral position), respectively. The AHD difference (AHD_diff) was defined as the difference between the AHD and AHD_stress values. Receiver operating characteristic curve analysis was performed to determine cutoff values for significant variables. RESULTS No difference in the mean preoperative AHD was found between the healed group (7.5 ± 2.0 mm) and healing failure group (6.9 ± 2.2 mm, P = .234). The AHD_diff value was significantly higher in the healed group (4.4 ± 2.1 mm) than in the healing failure group (3.0 ± 2.0 mm, P = .002; cutoff, 3.2 mm). Patients with an AHD_diff value ≥ 3.2 mm showed a lower healing failure rate (28.9% vs. 71.1%, P < .001) and higher functional scores than patients with an AHD_diff value < 3.2 mm. The AHD_diff value was higher in patients with an American Shoulder and Elbow Surgeons (ASES) score ≥ 80 (4.9 ± 1.9 mm) than in those with an ASES score < 80 (3.1 ± 2.1 mm, P = .024). Among patients with healing failure, only the postoperative AHD showed a significant difference between those with an ASES score ≥ 80 (7.0 ± 2.5 mm) and those with an ASES score < 80 (4.8 ± 2.1 mm, P = .009; cutoff, 4.8 mm). CONCLUSION A reducible AHD, which increased by ≥ 3.2 mm under stress radiography, can be a favorable predictor of rotator cuff healing and function after arthroscopic repair of mRCTs. Our findings suggest that this new and simple radiologic parameter should be considered preoperatively and would be helpful to determine appropriate treatment strategies.

This study aimed to evaluate the effect of noninvasive electrical stimulation (ES) using transcutaneous direct current on facial nerve crush injury by assessing in vitro cellular responses including proliferation and differentiation using PC12 cells as well as by performing in vivo functional and morphological assessments. Compared to the non-treated cells, the cells subjected to ES treatment showed clear in vitro neurite outgrowth and enhanced expression of differentiation genes. In this animal model, functional assessment of recovery was performed using vibrissa movement orientation and electrically stimulated muscle action potential. Moreover, histological observation was performed using a transmission electron microscope. A higher score of recovered vibrissa movement and more significant reduction of the threshold of electrically evoked muscle action potential were observed in the ES group than in the control group. Furthermore, histomorphometric evaluation showed that the experimental group had statistically significantly higher axon counts than did the control group. Regenerative nerve fibers were prominent in the distal segments of the ES group.

Invasive mucormycosis is an uncommon but increasing life-threatening fungal infection. The present study investigated clinical characteristics and mortality among patients diagnosed as invasive mucormycosis infection. We retrospectively reviewed a total of 24 histologically proven cases of invasive mucormycosis at two tertiary care referral hospitals between November 2005 and February 2014. Overall survival was 50% (n = 12). The time between onset of symptom and diagnostic procedure proved to be associated with mortality (P = 0.009). In addition, preexisting renal failure and thrombocytopenia demonstrated trends toward a poor outcome in our study (P = 0.089 and 0.065, respectively). On multivariate regression analysis, delayed diagnostic procedure (more than 16 days after the onset of symptoms) was an independent predictor of mortality (OR= 12.34, 95% CI, 1.43-10.64; P = 0.022). Mucormycosis is a destructive fungal infection that is associated with high mortality rates, ranging from 40% to 100% depending on the form of disease. When a clinician suspects invasive mucormycosis infection, an early diagnostic procedure performed within 16 days from the onset of symptom and early initiation of antifungal therapy will lead to successful management of this highly fatal disease.

Endobronchial actinomycosis is a rare but important and challenging diagnosis to make. We report a case of 57 year-old man who presented with a fever and a right-sided chest pain diagnosed as an endobronchial actinomycosis. Chest computed tomography showed a segmental obstruction and consolidations in right middle lobe combined with an ipsilateral multiloculated pleural effusion. Bronchoscopic biopsy of a mass obstructing the medial segmental bronchus of right middle lobe revealed actinomycosis. This is the first reported case of primary endobronchial actinomycosis that presented with a chest pain and a complicated parapneumonic effusion. Primary endobronchial actinomycosis can be a cause of complicated parapneumonic effusion.

Background/Aims As the incidence rate of and mortality from pseudomembranous colitis (PMC) are increasing worldwide, it is important to study the simple predictive risk factors for PMC among patients with hospital-acquired diarrhea (HAD). This study focused on identifying the clinical risk factors that can easily predict PMC. Methods The presumed HAD patients were prospectively recruited at the Hallym University Kangdong Sacred Heart Hospital. Results Age of 70 and older (adjusted odds ratio [OR], 1.76; 95% confidence interval [CI], 1.12 to 0.75), use of proton pump inhibitors (adjusted OR, 4.07; 95% CI, 2.512 to 6.57), use of cephalosporins (adjusted OR, 2.99; 95% CI, 1.82 to 4.94), and underlying cancer (adjusted OR, 1.72; 95% CI, 1.04 to 2.82) were independent risk factors for PMC in the multivariate logistic regression analysis. The prevalence of PMC was very low in the patients with HAD who exhibited no risk factors. Conclusions The risk factors for PMC in patients with HAD included cephalosporin use, proton pump inhibitor use, old age, and cancer. Considering the strongly negative predictive values of these risk factors, endoscopic evaluation can be delayed in patients with HAD without risk of developing PMC.

Objectives The purpose of this study was to evaluate the synergic effect of recombinant human bone morphogenetic protein-2 (rhBMP-2) and low-level laser therapy (LLLT) on bisphosphonate-treated osteoblasts. Materials and methods Human fetal osteoblast cells (hFOB 1.19) were cultured with 100 µM alendronate. Low-level Ga-Al-As laser alone or with 100 ng/mL rhBMP-2 was then applied. Cell viability was measured with MTT assay. The expression levels of receptor activator of nuclear factor kappa-B ligand (RANKL), macrophage colony-stimulating factor (M-CSF), and osteoprotegerin (OPG) were analyzed for osteoblastic activity inducing osteoclastic activity. Collagen type and transforming growth factor beta-1 were also evaluated for bone matrix formation. Results The results showed that rhBMP-2 and LLLT had a synergic effect on alendronate-treated osteoblasts for enhancing osteoblastic activity and bone matrix formation. Between rhBMP-2 and LLLT, rhBMP-2 exhibited a greater effect, but did not show a significant difference. Conclusion rhBMP-2 and LLLT have synergic effects on bisphosphonate-treated osteoblasts through enhancement of osteoblastic activity and bone formation activity.

Multi-layered TiO2 nanostructured films were fabricated to improve the light harvest efficiency of the dye-adsorbed TiO2 electrode in dye-sensitized solar cells (DSSCs) by light scattering. Three different structures of TiO2 electrodes, with layers consisting of TiO2 pastes with average diameters of 9, 20, and 300 nm, respectively, were fabricated and their photovoltaic effects on the DSSC devices were investigated. By utilizing the multi-layered TiO2 electrode constructed using the three different TiO2 pastes, the overall power conversion efficiency of the DSSC devices in the PEG-based electrolyte was increased to 5.24% under irradiation of 100 mW/cm2 at AM 1.5.

The dye-sensitized solar cell devices using PEDOT:PSS films as counter electrodes have the lower production cost and more simple fabrication process than devices using Pt counter electrode. To enhance the power conversion efficiency of devices, we fabricated DSSC devices using thermal treated poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT:PSS) as counter electrodes. The power conversion efficiency of DSSC device using a counter electrode based PEDOT:PSS film treated at 45°C for 720 min achieved a value of 3.22%.

Purpose Tenofovir disoproxil fumarate (TDF) is commonly prescribed as a fixed-dose, co-formulated antiretroviral drug for HIV-1 infection. The major concern of long-term TDF use is renal dysfunction. However, little is known about the long-term patterns of changes in renal function in HIV-infected Koreans receiving TDF. Materials and methods We prospectively followed 50 HIV-infected Koreans, performing laboratory tests every 3 months during the first year and every 6 months for the next 2 years. Urine N-acetyl-β-D-glucosaminidase (NAG) and plasma cystatin-C were measured using samples collected in the first year. Data on renal function were retrospectively collected on HIV-infected patients receiving first-line TDF (n=40) and in antiretroviral therapy (ART)-naive patients (n=24) for 3 years. Renal function was evaluated as estimated glomerular filtration rate (eGFR) from serum creatinine [Modification of Diet in Renal Disease (MDRD)] and cystatin-C. Results The eGFR (cystatin-C) showed significant changes from 0 to 48 wks (p=0.002), with the lowest levels at 24 wks (84.3±18.8 mL/min vs. 90.3±22.5 mL/min, p=0.021 by post hoc test). Urine NAG levels did not differ at 0, 12, 24, and 48 wks, although eGFR (MDRD) significantly decreased from 0 (98.7±18.9 mL/min/1.73 m²) to 144 wks (89.0±14.7 mL/min/1.73 m²) (p=0.010). The first-line TDF group had significantly lower eGFR (MDRD) than the ART-naive group at 144 wks (89.7 mL/min/1.73 m² vs. 98.4 mL/min/1.73 m², p=0.036). Thirteen (26%) participants experienced a decrease in renal impairment of 10 mL/min/1.73 m² in eGFR (MDRD) at 144 wks. Conclusion These data suggest that clinically meaningful renal injury can develop in HIV-infected Koreans receiving long-term TDF.

PURPOSE Pentraxin 3 (PTX3) has been suggested to be a prognostic marker of mortality in severe sepsis. Currently, there are limited data on biomarkers including PTX3 that can be used to predict mortality in severe sepsis patients who have undergone successful initial resuscitation through early goal-directed therapy (EGDT). MATERIALS AND METHODS A prospective cohort study was conducted among 83 severe sepsis patients with fulfillment of all EGDT components and the achievement of final goal. Plasma PTX3 levels were measured by sandwich ELISA on hospital day (HD) 0, 3, and 7. The data for procalcitonin, C-reactive protein and delta neutrophil index were collected by electric medical record. The primary outcome was 28-day all-cause mortality. RESULTS 28-day all-cause mortality was 19.3% and the median (interquartile range) APHCH II score of total patients was 16 (13-19). The non-survivors (n=16) had significantly higher PTX3 level at HD 0 [201.4 (56.9-268.6) ng/mL vs. 36.5 (13.7-145.3) ng/mL, p=0.008]. PTX3 had largest AUC(ROC) value for the prediction of mortality among PTX3, procalcitonin, delta neutrophil index, CRP and APACHE II/SOFA sore at HD 0 [0.819, 95% confidence interval (CI) 0.677-0.961, p=0.008]. The most valid cut-off level of PTX3 at HD 0 was 140.28 ng/mL (sensitivity 66.7%, specificity 73.8%). The PTX3 and procalcitonin at HD 0 showed strong correlation (r=0.675, p

To predict structure-borne interior noise using CAE simulation, it is important to establish a model for both the noise and vibration transfer path, as well as the excitation source. In the passenger vehicle, powertrain and road induced loads are major input sources for NVH. This paper describes a process to simulate the structure-borne road noise to 150Hz. A measured road surface is used for input for the simulation. Road surface data, in the form of height vs. distance, is converted to enforced motions at the tire patch in the frequency domain for input to the vehicle system model. The input loads are validated by the comparison of wheel hub excursions. The ability of the CAE simulation model to predict interior acoustic responses is shown by the comparison of the simulation results with measured vehicle interior responses.