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Recently, special behavior of interfacial tension during and after microwave irradiation was found. To understand the behavior in more details, microwave irradiation pattern was changed in this study. Higher power and longer irradiation time, which do not cause the boiling at the interface, are better for the reduction of interfacial tension and irradiation retention. Accordingly, the quick thermal response of microwave is essential for modification of interface compared to the conventional heating. In this way, interfacial tension does not return quickly to the original value, and effect of the reduction slowly disappeared for a few weeks.

Demulsification is a fundamental process in many industries, including food, petroleum production and refining, with ongoing research into cheaper and more efficient processes. Microwaves have been considered as a low-cost and efficient method to speed demulsification: they can pass through the non-polar oil phase to be absorbed in the polar aqueous phase, effectively targeting the liquid-liquid interface. This study uses in-situ measurement of interfacial tension to investigate the effect of repeated short duration microwave irradiation on an oil-water interface in the presence of the non-ionic surfactant, Triton X-100. It was previously shown that a high energy concentration at the interface – achieved by microwave irradiation – resulted in rapid increases in interfacial tension. In this paper, the mechanism behind the change in interfacial tension induced by microwave irradiation is discussed: we propose that the rapid switching of the induced electromagnetic field causes disorder and desorption of surfactant adsorbed at the oil-water interface, leading to the short-term increase in interfacial tension. Management of the overall energy concentration is achieved by patterns of short-term pulsed irradiation to avoid boiling. The results indicate that disruption of the bonding network in the interfacial layer, and hence effective modification of interfacial tension, can be achieved by repeated irradiation of high power microwaves without leading to boiling. A previously discussed dimensionless number was used to characterize the extent of energy concentration at the interface in each experiment.

The behaviour of a long-tailed surfactant (Triton X-405) at the water-octane interface was monitored in-situ during microwave heating in the presence of an electrolyte (NaCl). The interfacial tension and bulk temperature were analysed during and after pulsed microwave irradiation. The energy concentration at the interface, which we propose affects the molecular behaviour at the interface, was characterised by a dimensionless number recently proposed by our group. Although the non-ionic surfactant layer was stabilised by the electrolyte solutions, rapid changes to the interfacial conditions, particularly the movement and desorption of surfactants at the interfacial layer, were triggered by pulsed (short, intermittent) irradiation of high microwave power. The dimensionless number, which incorporates both interfacial and bulk properties, can be used as an effective indicator for determining the heating behaviour by accounting for the ability for energy to dissipate through the bulk solutions. The results can be useful to determine an optimal condition for a rapid disruption of the surfactant layer without causing boiling at the interface, making it possible to target conditions desirable for the de-emulsification process.

In our recent study, a new dimensionless number for microwave local heating at an interface was proposed for explanation of surfactant desorption behaviour in water and oil system. In this study, interfacial behaviour for both boiling and surfactant desorption at water/decane interface was investigated. In particular, a system of water phase with a non-ionic surfactant (Triton X-100) and NaCl was used. Several pulsed irradiation patterns were employed to vary the microwave energy density, and interfacial tension was measured at each condition. It was found that Triton X-100 layer in NaCl aqueous solution is more resistant to interfacial boiling than the Triton X-405 layer in a previous study. The dimensionless number can be used as an indicator to distinguish stable heating and boiling regions. For industrial practices, preventing boiling is desirable to get surfactant desorption efficiently and stably. The results present a practical method to maximum microwave effect on oil/water interface.

In previous study, the interfacial tension during microwave irradiation was measured in the presence of the non-ionic surfactant, Triton X-100. If the surfactant is short, quick increase during the pulse irradiation was observed due to desorption caused by the quick thermal response of microwave. Although operation of microwave irradiation would be useful for demulsification processes, combinations of two liquids and surfactant are various and need further studies. Accordingly, optimization of microwave local heating is required for industrial application of this technique. In this study, desorption of longer surfactant, Triton X-405 as a result of microwave irradiation was investigated at different power, and dimensionless number for the local heating around the interface was proposed to estimate surfactant behaviour for the desorption and disorder quantitatively.

This paper proposes a low latency incremental redundancy hybrid ARQ (IR-HARQ) scheme for the wireless local area network (WLAN) system. The proposed scheme adopt the rate compatible low-density parity-check (RC-LDPC) code based on IEEE802.11n LDPC codes and ensure backward compatibility with WLAN devices by using the current WLAN control frame. Additionally, it enables to minimize the retransmission latency by selection of an optimal retransmission data length based on the mutual information (MI). Through computer simulations, it has confirmed that the proposed scheme can reduce the required SNR by 2.6 dB to achieve a system throughput of 15 Mbps compared with the retransmission scheme of the current WLAN system.

This paper proposes an incremental redundancy hybrid ARQ (IR-HARQ) scheme for the wireless local area network (WLAN) system employing multiband simultaneous transmission. The proposed scheme adopt the rate compatible low-density parity-check (RC-LDPC) codes based on IEEE802.11n LDPC codes and ensure backward compatibility with WLAN devices by using the current WLAN control frame. Additionally, it enables to minimize the retransmission latency by selection of an optimal retransmission data length based on the mutual information (MI) for each frequency band. Through computer simulations, it has confirmed that the proposed scheme can reduce the required SNR by 2.9 dB to achieve a system throughput of 10 Mbps compared with the retransmission scheme of the current WLAN system.

Molybdenum disulfide (MoS2) has recently received much attention for nanoscale electronic and photonic applications. To explore the intrinsic properties and enhance the performance of MoS2-based field-effect transistors, thorough understanding of extrinsic effects such as environmental gas and contact resistance of the electrodes is required. Here, we report the effects of environmental gases on the transport properties of back-gated multilayered MoS2 field-effect transistors. Comparisons between different gases (oxygen, nitrogen and air and nitrogen with varying relative humidities) revealed that water molecules acting as charge-trapping centers are the main cause of hysteresis in the transfer characteristics. While the hysteresis persisted even after pumping out the environmental gas for longer than 10 h at room temperature, it disappeared when the device was cooled to 240 K, suggesting a considerable increase in the time constant of the charge trapping/detrapping at these modestly low temperatures. The suppression of the hysteresis or instability in the easily attainable temperature range without surface passivation is highly advantageous for the device application of this system. The humidity dependence of the threshold voltages in the transfer curves indicates that the water molecules dominantly act as hole-trapping centers. A strong dependence of the on-state current on oxygen pressure was also observed.

Objective:Toevaluatethesignificance ofpreoperativeclinicopathologicalfactors,includingserumcarcinoembryonicantigen(CEA),aswellas postoperative clinicopathological factors in T1-2N1M0 patients with non-small cell lung cancer who underwent curative pulmonary resection. Methods: Twenty T1N1M0 disease patients and 25 T2N1M0 patients underwent standard surgical procedures between September 1996 and December 2005, and were found to have non-small lung cancer. As prognostic factors, we retrospectively investigated age, sex, Brinkman index, histologic type, primary site, tumor diameter, clinical T factor, clinical N factor, pathological T factor, preoperative serum CEA levels, surgical procedure, visceral pleural involvement, and the status of lymph node involvement (level and number). Results: The overall 5-year survival rate of all patientswas59.6%.In univariateanalysis,survivalwasrelatedto age(

The aim of this study was to evaluate our personal experience with video-assisted thoracoscopic lobectomy and compare survival between this procedure and conventional lobectomy via open thoracotomy in patients with clinical stage IA non-small cell lung carcinoma. Between May 1997 and December 2004, 140 patients with clinical stage IA non-small cell lung carcinoma had either VATS lobectomy (VATS group, 84 patients) or standard lobectomy via open thoracotomy (open group, 56 patients) performed in our hospital. We compared overall survival, disease-free survival and recurrence between the two groups. The overall survival rate five years after surgery was 72% in the open group and 82% in the VATS group. There were no significant differences in the overall survival rate between the two groups. The disease-free survival rate five years after surgery was 68% in the open group and 80% in the VATS group. There were no significant differences in the disease-free survival rate between the two groups. Five patients in the open group developed distant recurrence, whereas one patient developed regional recurrence. In the VATS group six patients developed distant recurrence, whereas one patient developed regional recurrence. We consider VATS lobectomy to be one of the therapeutic options in patients with clinical stage IA non-small cell lung carcinoma.

The psychological effects of surgery have received little attention in patients with lung cancer, so it is unclear how much psychological support is required by these patients. This study was done to assess the mental state of patients with lung cancer before and after surgery and to determine their need for psychological care.A group of 165 patients with lung cancer scheduled for surgical treatment were included in this study. They were asked to complete the Profile of Mood States questionnaire before surgery and on discharge after completion of treatment. The data on mood from the questionnaires were analyzed.Tension-anxiety improved significantly after surgery, whereas the fatigue score increased significantly. The scores for depression-dejection and confusion were elevated before surgery and were unchanged afterward.Patients with lung cancer were depressed before surgery and remained depressed after their operations, although postoperative tension-anxiety diminished. These results indicate that lung cancer patients need psychological support to alleviate depression during the perioperative period.

Background: This study endeavored to clarify the location, frequency, and prognostic value of metastatic lymph nodes in the mediastinum among patients with left upper lung cancer who underwent complete dissection of the superior mediastinal lymph node through a median sternotomy. Methods: Forty-four patients with left upper lobe cancer underwent extended radical mediastinal nodal dissection (ERD), all of whom were analyzed in this retrospective study. The group comprised 12 females and 32 males, with ages ranging from 28 to 70 years (median age, 60 years). Mediastinal nodal status was assessed according to the systems of Mountain/Dresler 7 and Naruke 8. The clinicopathological records of each patient were examined for prognostic factors, including age, sex, histology, tumor size, c-N number, preoperative serum CEA level, metastatic stations and distribution of metastatic nodes according to Naruke’s system 8. The superior mediastinal lymph nodes which cannotbedissectedthrougha leftthoracotomy(bilateral#1and#2,#3,right#3a,andright#4accordingtoNaruke’smap8 weredefinedasextrasuperior mediastinal nodes for left lung cancer (ESMD). Results: Fourteen patients had one or more metastases to mediastinal lymph nodes, among whom the most common metastatic station was the aortic nodes: 71.4% had metastasis to #5 or #6 (57.1% to #5 and 50% to #6). The next mostcommonmetastatic station wasthe left tracheobronchialnodes (42.8%).Metastasis to the ESMDoccurredin 7 of the 44study subjects (16%), representing a 50% rate of occurrence (7/14) among those with mediastinal nodal involvement. Univariate analysis found that CN factor and aortic nodal involvement (#5, #6) were significant predictive factors for ESMD metastasis. Multivariate analysis determined that only aortic nodal involvement was significant (p = 0.008). Furthermore, ESMD metastasis was rare (5.8%) in the absence of aortic node metastasis. The overall survival rate at 5 years was 50% among the patients without ESMD metastasis. However, the survival rate was 32% at 3 years and 0% at 5 years among the seven patients with ESMD metastasis. Conclusions: The aortic lymph node is the most common site of metastasis from left upper lobe cancer. Multivariate analysis demonstrated that aortic nodal involvement was a significant predictive factor for ESMD metastasis. Based upon the rates of metastasis and the post-operative prognosis in our study patients, dissection of aortic nodes and left tracheobronchial nodes may be important for patients with left upper lobe cancer. Whether ESMD dissection has a beneficial effect on prognosis remains controversial.

Objective: We worked to devise a new way to prevent postoperative persistent air leaks in high-risk pulmonary surgery patients. Methods: From November 1993 to June 2002, 60 patients with difficult to control intraoperative pulmonary air leakage were treated using bioabsorbable polyglycolide felt patches soaked in fibrin glue to cover the leakage site. Results: After application, the felt patch adhered tightly to the lung surface without peeling off, enabling good leakage closure with only 2 ml of fibrin glue used. Air leakage was controlled successfully in 52 (86.7%) of the 60. Four of the 8 patients in whom this method failed to stop air leakage also developed mild pyothorax, with 2 requiring a second operation by video-assisted thoracic surgery. Leakage was eventually controlled in all patients, with no postoperative deaths relating to air leakage. Conclusions: Fibrin-glue-soaked bioabsorbable felt patches effectively seal intraoperative intractable air leaks. Felt patch use may increase the risk of postoperative infection. It should be considered for use on patients with fistulas that cannot be controlled by direct closure or otherwise intraoperatively and who may potentially develop uncontrollable air leakage postoperatively.

During the operation of multiuser multiple-input-multiple output (MU-MIMO) algorithms, some antennas of BS or UEs may neither transmit nor receive signals due to the long distance or unexpected damages. Therefore, the BS cannot obtain the channel state information (CSI) from/to these antennas. Without these CSI, the performance of algorithm is degraded. We call this effect as ‘broken antenna effect (BAE)’. To cope with this issue, this paper proposes a process to regularize the channel matrix by replacing the missing CSI with zero(s) and setting nonzero values to diagonal elements. Then, it is confirmed through computer simulation that the proposed method can adjust the number of transmitting parallel streams according to the number of ‘broken’ antennas, and provide MU-MIMO transmission with maximum diversity order without any change of the precoding process.

Legionella spp are well recognized as one of the etiologic factor in pneumonia, but it is difficult to distinguish the clinical features of Legionella infection from pneumonia due to other causes. The objective of the present study was to examine the clinical characteristics of community-acquired Legionella pneumonia in elderly patients. We reviewed the clinical, laboratory and radiographic findings in 8 patients diagnosed as having pneumonia caused by Legionella. The diagnosis was confirmed by the presence of urinary antigen, bacterial culture, polymerase chain reaction (PCR) and serum antibody. There were 6 men and 2 women, whose ages ranged from 76 to 85 years. All patients had fever and hypoxia, four patients had respiratory symptoms. The initial chest X-ray findings were varied--consolidation, ground glass opacity, pleural effusion and linear shadow. Urinary antigen was positive in 4 patients, bacterial culture in 2, PCR on the sputum in 3 and serum antibody in 2 patients. As pneumonia caused by Legionella often becomes life-threatening, especially in elderly people, it is imperative to diagnose it at the initial stage. In this study, urinary antigen proved to be the most useful diagnostic means. However, it is important to confirm the diagnosis through plural examinations.

We report a case of aspergilloma in an 80-year-old male patient who had no identifiable underlying disease before surgery for pneumothorax. He was hospitalized for left pneumothorax. A chest CT revealed a large bulla in the left lung apex with a nodule (diameter; 1.5 cm) at the edge of the bulla. After thoracodocesis, air leakage persisted and a large bulla and nodule were resected. Aspergillus was detected histopathologically in the nodule. Treatment with itraconazole 200 mg a day followed, and 4 months later he had no recurrent pneumothorax or Aspergillus infection.

Background We tried to clarify whether the histologic subtypes and the size of the solid component of an adenocarcinoma are more important predictive factors for invasiveness or prognosis than is total tumor size, even in lung adenocarcinomas that were 2 cm or smaller. Methods Between 1996 and December 2005, after standard surgical treatment, 82 patients were diagnosed as having adenocarcinoma with a maximum diameter of 2 cm or less. The group comprised 37 females and 45 males, with ages ranging from 41 to 80 years (median, 64). The clinicopathologic records of the patients were examined with regard to age, sex, nodal status, tumor size (largest diameter of the total tumor as well as the largest diameter without the bronchioloalveolar carcinoma [BAC] component [solid component]), serum carcinoembryonic antigen level, and histologic type. These variables were analyzed as risk factors for vascular or lymphatic invasion, lymph node metastasis, and prognosis. Histologic subtype was classified into two groups: mixed BAC (mixed adenocarcinoma with BAC) and minimal or non-BAC (tumors with little or no BAC component). Results Histologic subtype was a significant predictive factor both for invasiveness (vascular or lymph vessels) and lymph node metastasis, in both univariate and multivariate analysis. Tumor diameter was not a significant factor in either univariate or multivariate analysis (p = 0.28, 0.15, respectively). However, diameter excluding the BAC component was a significant factor for invasiveness in mixed BAC type (p = 0.035), whereas total diameter was not significant (p = 0.28). Finally, histologic subtype and lymph node metastasis were significant prognostic factors for survival in both univariate (p = 0.03, 0.05, respectively) and multivariate (p = 0.04, 0.05, respectively) analyses. The 5-year survival rate was 94.4% (94.1% for pN0) for the mixed BAC type and 71.4% (78.7% for pN0) for the minimal or non-BAC type (p = 0.009; p = 0.04 for pN0 nodes). Conclusions Small adenocarcinomas can be classified into two categories. The first category is a minimal or non-BAC adenocarcinoma that shows aggressive biological behavior. The second category is a mixed BAC, which demonstrates less invasive or aggressive biological behavior than the minimal or non-BAC type, with the degree of invasiveness being associated with the size of the non-BAC component.

Pulmonary lymphangioleiomyomatosis (LAM) is a rare and progressive disease of young women that usually causes death from respiratory failure. Here we report an early case that was diagnosed by thoracoscopy. A 28-year-old woman presented to a local clinic with chest pain and her chest X-ray film showed left pneumothorax. After placement of a chest tube, the lung re-expanded fully. Following the recurrence of left pneumothorax, she was referred to our hospital and underwent video-assisted thoracoscopic surgery (VATS). However, left pneumothorax recurred again one month later. She underwent a second thoracoscopic operation, during which a bulla was recognized in the lingular segment of the left lung and was resected. On histological examination of the surgical specimen findings consistent with LAM were obtained. Taking the preoperative imaging findings and the thoracoscopic findings into consideration, a diagnosis of early lymphangioleiomyomatosis was made. Thoracoscopic management of pneumothorax in young women can facilitate the early diagnosis of this condition.

Rosai et al. published the World Health Organization (WHO) classification of thymic epithelial tumors in 1999, and its clinical usefulness seems to be established. It is our purpose to find the clinically relevant diagnostic points in the WHO Histological Classification of Thymoma.Thymomas surgically removed from 100 consecutive patients at Juntendo University Hospital between October 1983 and February 2002 were classified according to the WHO histological classification. We assessed overall survival and recurrence-free rate calculated for each tumor type in the WHO classification compared with those of tumors classified by the Masaoka system.The thymic epithelial tumors in this series comprised 10 type A, 15 type AB, 18 type B1, 21 type B2, 33 type B3, and 3 type C tumors according to the WHO classification. Based on the Masaoka system, the disease was stage I in 53 patients, stage II in 30, stage III in 15, and stage IV in 2. The 15-year recurrence-free rate was 100% for type A, AB and B1, while the rates for types B2 and B3 were 66.7% and 54.5%, respectively. The 10-year recurrence-free rate was 66.7% for type C. The 15-year recurrence-free rate of the 64 patients with type A, AB, B1, and B2 thymomas was significantly higher from that of the 33 patients with type B3 thymoma (p=0.0026).When using the WHO classification, it is critical to distinguish type B3 thymoma from other tumor types.

Diffuse pleural mesothelioma is a rare condition with a poor prognosis. Recent reports have indicated that extensive surgery combined with chemotherapy and radiotherapy prolongs the survival of selected patients with early disease. Thoracoscopy allows complete visualization of the pleural cavity and provides high-quality biopsy samples. We present a case of successful diagnosis of bilateral pleural mesothelioma by thoracoscopy. It is important to observe the contralateral pleural cavity by thoracoscopy to confirm the presence or absence of a tumor before considering extrapleural pneumonectomy for mesothelioma.

BACKGROUND Many histologic classifications of thymic epithelial tumors have been reported to date, but to the authors' knowledge, none of them closely reflect the clinical behavior or prognosis of the tumor. Therefore, it is necessary to establish a biologic marker for thymic epithelial tumors. Variants of CD44 may be important in promoting tumor progression and metastasis. Accordingly, the expression of CD44 isoforms in thymic epithelial neoplasms was investigated using immunohistochemistry to assess their possible value as prognostic indicators. METHODS Expression of CD44v6 in thymic epithelial tumors was investigated with immunohistochemistry using consecutive surgical specimens resected from 108 patients between 1983 and 2002 at Juntendo University Hospital in Tokyo, Japan. RESULTS Among the 108 thymic epithelial tumors, 70 were negative for CD44v6, 20 were weakly positive, and 18 were strongly positive. The status of CD44v6 expression (negative vs. weakly plus strongly positive) was found to be correlated with the tumor stage according to the Masaoka staging system (noninvasive vs. invasive tumors) (P = 0.0214). When patients with tumors that were negative and weakly positive for CD44v6 expression were combined, the 5-year, 10-year, and 15-year recurrence-free survival rates were 98.2%, 95.9%, and 86.1%, respectively, whereas the corresponding rates for patients with strongly positive tumors were 73.5%, 73.5%, and 55.1%, respectively. Therefore, these two groups demonstrated a significant difference with regard to recurrence-free survival (P = 0.0172). CONCLUSIONS CD44v6 expression in thymic epithelial neoplasms demonstrated a significant difference based on the World Health Organization classification, the Masaoka stage (invasive vs. noninvasive tumors), and recurrence, if an appropriate cutoff value was chosen in each case. This suggests that CD44v6 can be used as a marker that reflects the stage of thymic tumors. Cancer 2005. © 2005 American Cancer Society.

We measured thymidylate synthase (TS) activity, dihydropyrimidine dehydrogenase (DPD) activity and TS inhibition rate (TSIR) in tumor tissue and lymph node metastasis, considered predictors of response to DIFs, in patients with lung cancer.Fourteen patients with non-small cell lung cancer (NSCLC) were given UFT for 1-2 weeks before surgery. Total TS activity (total TS), TSIR and DPD activity were measured in tumors, lymph node metastases and normal lung and lymph nodes.Total TS activity and DPD activity were significantly higher in lung tumors than in normal lung (TS, p = 0.0225; DPD, p0.0001). Total TS activity was slightly but not significantly higher in lymph node metastases than in normal lymph nodes. DPD activity and TSIR were similar in the other tissues.After preoperative treatment with UFT, TS and DPD activities are significantly higher in lung tumor tissue than in normal lung tissue in patients with NSCLC.