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Two grain boundaries (GBs) in a Sn-alloy film exhibited different morphological changes during thermal cycling: whisker growth and GB sliding. Along GB-I, pervasive nucleation of high-angle and low-angle GBs occurred, with whisker growth of some shallow grains depending on sub-surface GB geometry. Most whiskers showed substantial changes of crystallographic orientation and surface normal relative to the parent grains. Along GB-II, GB sliding was characterized by mass accumulation, crystallographic rotation, and localized yielding. Results for two GBs suggest that grain crystallography and GB geometry, particularly GB inclination, are critical in determining the extent of new grain formation and subsequent whisker growth.

A novel hybrid biodegradable Nuss bar model was developed to surgically correct the pectus excavatum and reduce the associated pain during treatment. The scheme consisted of a three-dimensional (3D) printed biodegradable polylactide (PLA) Nuss bar as the surgical implant and electrospun polylactide–polyglycolide (PLGA) nanofibers loaded with lidocaine and ketorolac as the analgesic agents. The degradation rate and mechanical properties of the PLA Nuss bars were characterized after submersion in a buffered mixture for different time periods. In addition, the in vivo biocompatibility of the integrated PLA Nuss bars/analgesic-loaded PLGA nanofibers was assessed using a rabbit chest wall model. The outcomes of this work suggest that integration of PLA Nuss bar and PLGA/analgesic nanofibers could successfully enhance the results of pectus excavatum treatment in the animal model. The histological analysis also demonstrated good biocompatibility of the PLA Nuss bars with animal tissues. Eventually, the 3D printed biodegradable Nuss bars may have a potential role in pectus excavatum treatment in humans.

Background Although thoracoscopic stapled bullectomy is a standard procedure for primary spontaneous pneumothorax (PSP), the postoperative recurrence rate is high. We investigated whether using a Vicryl (Ethicon, Somerville, NJ) mesh to cover the staple line after bullectomy reduces the postoperative recurrence rate. Methods Our single-blind, parallel-group, prospective, randomized controlled trial at 2 medical centers in Taiwan studied patients with PSP who were aged 15 to 50 years and required thoracoscopic bullectomy. On the day of operation, patients were randomly assigned (1:1) to receive Vicryl mesh (mesh group) or not (control group) after thoracoscopic bullectomy with linear stapling and mechanical apical pleural abrasion. Randomization was achieved using computer-generated random numbers in sealed envelopes. Our primary end point was the pneumothorax recurrence rate within 1 year after the operation ( clinicaltrials.gov number, NCT01848860 .) Results Between June 2013 and March 2016, 102 patients were assigned to the mesh group and 102 to the control group. Within 1 year after operation, recurrent pneumothorax was diagnosed in 3 patients (2.9%) in the mesh group compared with 16 (15.7%) in the control group (P = .005). The short-term postoperative results and hospitalization duration were comparable between the groups. Conclusions For thoracoscopic bullectomy with linear stapling and mechanical apical pleural abrasion, the use of a Vicryl mesh to cover the staple line is effective for reducing the postoperative recurrence of pneumothorax. Vicryl mesh coverage can be considered an optimal adjunct to the standard surgical procedure for PSP.

Four different types of stress relaxation responses have been observed in terms of local microstructural changes along grain boundaries (GBs) in large-grained high-Sn (Sn-3.0Ag-0.5Cu) solder films after thermal cycling. The grain boundaries were characterized using scanning electron microscopy, electron back scattered diffraction, and focused-ion beam (FIB) cross-section imaging. While the anisotropic coefficient of thermal expansion of Sn plays an important role in determining which boundaries have high local stresses relative to the film plane and trace of the grain boundary plane during thermal cycling, the four different relaxation behaviors of specific boundaries (no observable changes, surface defect/whisker formation, GB sliding, or a combination of GB sliding and whisker/defect formation) were determined by a combination of Sn anisotropy, the GB geometry, and crystallographic orientation relative to the film plane. The ability to separate GB sliding from surface defect formation provides insights into how long, straight whiskers form in polycrystalline thin films, particularly with respect to grain rotation at the early stages of their growth.

Kuo-Sheng Liu,1 Wei-Hsun Chen,1 Cheng-Hung Lee,2 Yong-Fong Su,3 Shih-Jung Liu3,4 1Department of Thoracic and Cardiovascular Surgery, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan, Republic of China; 2Division of Cardiology, Department of Internal Medicine, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan, Republic of China; 3Department of Mechanical Engineering, Chang Gung University, Taoyuan, Taiwan, Republic of China; 4Department of Orthopedic Surgery, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan, Republic of China Background: The most common complaint after the Nuss procedure is severe postoperative chest pain. The aim of this study was to evaluate the effectiveness of analgesic-eluting biodegradable nanofibers in pain relief after the Nuss procedure.Materials and methods: Poly(D,L)-lactide-co-glycolide, lidocaine, and ketorolac were dissolved in 1,1,1,3,3,3-hexafluoro-2-propanol. This solution was electrospun into a nanofibrous membrane. The elution method and high-performance chromatography were used to characterize the in vitro drug release. Stainless steel bars with and without coating of the analgesic-eluting nanofibrous membrane were implanted underneath the sternums of New Zealand white rabbits. The in vivo characteristics were further investigated.Results: The in vitro study showed that the biodegradable nanofibers released high doses of lidocaine and ketorolac within 10 days. The in vivo study demonstrated high local and systemic concentrations of lidocaine and ketorolac. The serum creatinine level was unaffected. Animals that received implants of the analgesic-eluting nanofiber-coated stainless steel bar exhibited significantly greater food and water ingestion and physical activity than the control group did, indicating effective pain relief.Conclusion: The proposed analgesic-eluting biodegradable nanofibers contribute to the achievement of extended pain relief after the Nuss procedure, without obvious adverse effects, in an animal model. Keywords: analgesic-eluting, nanofibers, biodegradable, pectus excavatum, Nuss procedure

Objectives To present the technique of single-port video-assisted thoracoscopic mediastinal tumour resection, which includes limited thymectomy, extended thymectomy, cyst excision and posterior mediastinal tumour excision, and the early results of resection with the use of this technique. Methods Twenty-nine patients with mediastinal tumours were treated with single-port thoracoscopic mediastinal resection at Chung Gung Memorial Hospital between April 2014 and May 2015.The surgical intervention was performed through the fourth or fifth intercostal space at the anterior axillary line. A 5- or 10-mm 30° video camera and working instruments were employed simultaneously at this incision site throughout the surgery. The perioperative variables and outcomes were collected and analysed retrospectively. Results Among the 29 cases included in the final analysis, 8 extended thymectomies, 5 limited thymectomies, 7 cyst excisions and 9 tumour excisions were performed successfully without the need for conversion. For the 29 patients who underwent single-port video-assisted thoracoscopic surgery (VATS), the mean operation time was 97.3 ± 31.2 min and the average blood loss was 34.1 ± 45.7 ml. The average length of the incision wound was 3.41 ± 0.76 cm and the average length of postoperative hospital stay was 3.75 ± 1.53 days. There were no mortalities, and mobility was achieved 30 days after surgery. Conclusions With regard to oncological concerns, the occurrence of postoperative myasthenia gravis or freedom from tumour recurrence is a paramount issue. Our cohort follow-up time was not long enough to address this, and more time and patients are needed for further evaluation. But our preliminary report showed that uniportal VATS for mediastinal tumour resection was a promising and safe technique with regard to short-term clinical outcome.

Androgen deprivation therapy (ADT) or orchiectomy is associated with an increased risk of osteoporosis or fracture. In this nationwide database analysis, we found that ADT or orchiectomy increased the risk of fracture in Chinese patients with prostate cancer. However, the magnitude of increase is seemingly not as large as that in Western populations. ADT using gonadotropin-releasing hormone (GnRH) agonists or orchiectomy is associated with an increased risk of osteoporosis or fracture. To investigate the effects of ADT duration or orchiectomy on any type of fracture in Asian patients with prostate cancer, we conducted this retrospective analysis using a nationwide database in Taiwan. We included 17,359 subjects who were newly diagnosed with prostate cancer between January 1, 1998, and December 31, 2007. The risk of first fracture was our primary endpoint. The rates of fracture from 12 months after prostate cancer diagnosis until the last follow-up date were 8.7 % for all patients, 7.1 % for patients who did not receive ADT or orchiectomy, 9.8 % for patients who received ADT, and 14.4 % for patients who received orchiectomy with or without ADT (P

To investigate the prognostic significance of lymphovascular invasion (LVI) in patients with esophageal squamous cell carcinoma (ESCC) treated with neoadjuvant chemoradiotherapy (nCRT). We retrospectively reviewed the charts of 416 consecutive patients with ESCC who underwent surgical resection following nCRT at the Chang Gung Memorial Hospital between 1998 and 2008. After exclusion of patients with non-R0 resection or showing no residual tumor (ypT0Nx), the histological tumor sections of 231 patients were reviewed for LVI. Univariate and multivariate analyses were used to identify the independent predictors of overall survival (OS). LVI was observed in 85 patients (36.8 %). The presence of LVI was related to close circumferential resection margins (CRMs), a greater depth of invasion, poor tumor differentiation, and an increased occurrence of lymph node metastases (LNM). The 5 year OS was significantly lower (10 %) in patients with LVI than in those without (31 %; p

Background Contactin-associated protein 2 (Caspr2) antibody is a neuronal surface antibody (NSAb) capable of causing disorders involving central and peripheral nervous systems (PNS). Thymoma can be found in patients with Caspr2 antibodies and is most frequently associated with PNS symptoms. Myasthenia gravis can be found in these patients, but Hashimoto thyroiditis (HT) has not been reported. Methods A 76-year-old woman presented with sub-acute-onset changes in mental status. Further investigations revealed thymoma and HT. The presence of NSAb was tested by immunofluorescence on human embryonic kidney-293 cells. Treatment included corticosteroids, azathioprine, thyroxine, plasmapheresis, and thymectomy. Results Caspr2 antibody was positive in serum but absent in CSF. Brain magnetic resonance imaging (MRI) showed diffuse cortical atrophy, but did not change significantly after treatments. Brain positron emission tomography (PET) revealed diffuse hypometabolism over the cerebral cortex. The patient's mental status only partially improved. Conclusions In Caspr2 antibody-associated syndromes, thymoma can occur in patients presenting only with LE, and HT can be an accompanying disease. Brain MRI and PET may not show specific lesions in limbic area. Patients with Caspr2 antibodies and thymoma may not have good prognosis.

A strategy for identifying the preferred sites and overall propensity of a Sn film to form whiskers has been developed based on film textures, local grain orientations, and elastic strain energy densities (ESEDs), with preferred sites predicted to be grains with local high ESEDs. Using β-Sn films with various textures, ESED distributions were simulated for elastic and thermoelastic stresses depending on isothermal aging or thermal cycling conditions. Local high ESEDs are preferentially induced in (110) or (100) oriented grains with c-axes nearly parallel to the film plane; films with overall low ESEDs have strong (100) textures for elastic stresses and strong (001) textures for thermoelastic stresses, suggesting low propensities to form whiskers. This work establishes a model for understanding the effect of the β-Sn anisotropy on whisker formation and provides guidelines for testing whether engineering specific film textures will reduce a film’s propensity to form whiskers.

Whisker and hillock formation in thin films is well known as a highly local mechanism for stress relaxation, where in many cases, only a few whiskers form out of thousands of grains in a film. In this article, the microstructural characteristics for specific grains to form whiskers in β-Sn films are discussed in light of our recent whisker growth model, establishing a relationship among grain boundary sliding limited Coble creep, surface grain geometry, and film stress for different stress conditions, including for thermal cycling. Through our recent finite-element simulations of stresses induced by room-temperature aging and thermal cycling of textured microstructures, the role of elastic and thermoelastic anisotropy in creating preferred whisker formation sites and the general propensity of a film to form whiskers have been proposed for a range of β-Sn film textures. Taken together, these models suggest a strategy for identifying the effects of local microstructure and β-Sn anisotropy on whisker formation. If these predictions are accurate, then whisker growth risk may be effectively reduced by engineering film microstructures and textures for specific applications and stress conditions.

Although esophagectomy traditionally is recommended to perform within 8 weeks after neoadjuvant chemoradiotherapy (nCRT), data from neoadjuvantly treated rectal cancer patients demonstrate that delayed surgery (>8 weeks) can maximize the effect of CRT. Despite these promising data, investigators are concerned that delayed surgery may lead to tumor repopulation. We report the impact of delayed surgery in patients with esophageal cancer who were treated with nCRT. We retrospectively studied 276 esophageal cancer patients treated with nCRT and surgery between 2002 and 2008. We compared perioperative complication, rate of pathological complete response (pCR), distribution of tumor regression grade (TRG), and overall survival (OS) in patients who underwent surgery within 8 weeks (group A) and after 8 weeks (group B) after nCRT. There were 138 patients in each group with similar pre/post-nCRT characteristics. Delayed surgery did not result in lower surgical risk or higher pCR rate. Survival outcome also did not improve following a longer surgery interval (5-year OS: group A vs. group B, 29 vs. 23 %; P = 0.3). On the contrary, a subgroup analysis showed that delayed surgery might be hazardous, especially in patients who demonstrate a good response after nCRT. The amount of residual cancer, as measured by TRG, increased significantly after a longer surgical interval (P = 0.024). Survival also decreased after a longer surgical interval (5-year OS ≤8 vs. >8 weeks, 50 vs. 35 %; P = 0.038). After nCRT, esophagectomy should be performed within 8 weeks, especially in patients with good response.

Direct evidence was obtained for the nucleation of surface grains through recrystallization and their growth into whiskers and hillocks during thermal cycling of Sn-alloy films. Shallow grains with low dislocation densities nucleated at pre-existing film grain boundaries and grew at the expense of deformed parent grains. Micro-diffraction analysis showed that parent grains have a high grain orientation spread, subgrain formation, and high dislocation density. The whisker and hillock grains have different orientations from the parent grains. A crystallographic orientation relationship between a surface defect grain and one of the parent grains was demonstrated with the misorientation axis lying in the active slip planes of the parent grain.

A whisker and hillock growth model based on local film microstructure, grain misorientation, and elastic strain energy density (ESED) as the driving force for growth was developed to predict preferred sites for growth. Local grain orientations and strains measured by synchrotron microdiffraction in nine regions containing whiskers or hillocks were compared with elastic finite element analysis simulations including Sn elastic anisotropy. Whisker and hillock grains were observed to have higher crystallographic misorientations with neighboring grains than generally observed in the microstructure. While elastic simulations predicted higher local out-of-plane elastic strains and ESEDs at those locations with high misorientations before growth, synchrotron measurements of out-of-plane strains of whisker and hillock grains after growth showed relaxation, with correspondingly low ESEDs calculated from measured strains. Hence, highly localized out-of-plane elastic strains and ESEDs of grains with high relative misorientations with their neighbors determined, at least in part, which grains became whiskers or hillocks.

Invisible near-infrared (NIR) fluorescence imaging with indocyanine green (ICG) has advantage in detecting for certain anatomy. The method is currently used in some types of surgery, such as sentinel lymph node (SLN) mapping, intraoperative solid tumor identification, and organ perfusion assessment. However, the literature of clinical application in thoracic surgery is lacking. This paper presents the advantages, current applications and potential developments of NIR fluorescence imaging with ICG in thoracic surgery.

Single-port video-assisted thoracoscopic surgery (VATS) has been widely applied recently. However, there are still only few reports describing its use in mediastinum tumor resection. We present the technique of single-port video-assisted thoracoscopic mediastinum tumor resection and compare it with conventional VATS with regard to short-term outcome. We retrospectively enrolled 105 patients who received mediastinum surgery in Chang Gung Memorial Hospital. Sixteen patients received sternotomy or thoracotomy, 29 patients received single-port VATS, and 60 patients received conventional VATS (3 ports). The operative time, blood loss, postoperation day 1 pain score, discharge day pain score, and postoperative hospital stay were compared. In order to establish a well balanced cohort study, we also use propensity scores match (1:1) to compare the short-term clinical outcome in 2 groups. No operative deaths occurred in this study. Single-port VATS was associated with shorter operative time, lower postoperation day 1 pain score, and shorter postoperation hospital stay in our cohort study (P = 0.001

Purpose To solve the problem of the basal descent movement in quantification of the regional left ventricular (LV) myocardial wall thickness (WTh) and wall thickening (%WT) in short-axis (SA) cine MRI for effectively assessing the regional wall motion of LV myocardium. Materials and Methods LV long-axis tagged MRI and SA cine MRI were performed to calculate the longitudinal translation and circumferential WTh of LV myocardium in eight normal volunteers. The new SA end-systolic thickness (EST) data were reconstructed from the original EST data, based on the quantified longitudinal translation of LV myocardium. Results The mean %WT of six segments in the basal section after correction was significantly different from that before correction in both intra- and inter-operator experiments. The polar map also showed the significant improvement of the variability of regional %WT and lack of quantification of %WT in the most basal SA slices after correction. Conclusion The proposed technique demonstrated an important advantage to calculate the %WT in the most basal SA myocardial tissue, which was considered difficult to be achieved using cine MRI. J. Magn. Reson. Imaging 2011;33:464–473. © 2011 Wiley-Liss, Inc.

Assistive technology so far has been focusing on promoting greater independence for people with disabilities by enabling them to perform tasks on a personal basis. For certain areas such as cognitive deficits, requirements for dual interface development must address the needs of target users as well as their caregivers. In this paper, we provide a location-based guiding and tracking service for people with mental illness in public transit system to help them travel from home to their workplace independently. Meanwhile their caregivers can monitor them in a nomadic or static way. Due to the lack of line-of-sight GPS signal in the area of underground mass rapid transit system, the WiFi signals are adopted for user locating. This service is implemented in collaboration with a supported employment program set up for people with severe mental illness.

The problem of the basal descent through-plane movement in quantitative measurement of regional left ventricular (LV) function has been recognized for a long time. But, it is a lack of sophisticated analysis to overcome the limitation.