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As the bioaccumulation of microplastics (MPs) is considered as a potential health risk, many efforts have been made to understand the cellular dynamics and cytotoxicity of MPs. Here, we demonstrate that label-free multicolor coherent anti-Stokes Raman scattering (CARS) microscopy enables separate vibrational imaging of internalized MPs and lipid droplets (LDs) with indistinguishable shapes and sizes in live cells. By simultaneously obtaining polystyrene (PS)- and lipid-specific CARS images at two very different frequencies, 1000 and 2850 cm–1, respectively, we successfully identify the local distribution of ingested PS beads and native LDs in Caenorhabditis elegans. We further show that the movements of PS beads and LDs in live cells can be separately tracked in real time, which allows us to characterize their individual intracellular dynamics. We thus anticipate that our multicolor CARS imaging method could be of great use to investigate the cellular transport and cytotoxicity of MPs without additional efforts for pre-labeling to MPs.

Data regarding predictors of the outcome in patients with community-acquired complicated parapneumonic effusion (CPPE) or empyema are insufficient. The aim of the present study was to investigate the prognostic factors in these patients.

The data regarding pulmonary artery stump thrombosis (PAST) after lung cancer surgery are insufficient. The aim of the present study was to evaluate the incidence, clinical characteristics, and prognosis of PAST. We retrospectively investigated the incidence and clinical characteristics of PAST among patients who underwent lung resection for lung cancer at 2 institutions. We compared the clinical parameters between PAST and pulmonary embolism (PE) and examined the clinical course of patients with PAST. Of the 1885 patients, PAST was found in 36 patients (1.9%). Right lower lobectomy (n = 13) and middle-lower bilobectomy (n = 9) were the most common types of surgery. The median time interval from lung resection to the detection of PAST was 3.8 months. Immobilization and a history of cerebrovascular disease were not observed in the PAST group. Most of the patients with PAST (91.7%) were diagnosed incidentally, whereas many patients with PE (75.9%) were symptomatic at the time of diagnosis. During the follow-up, one patient (2.8%) had contralateral PE complications. However, no patients in the PAST group experienced pulmonary thromboembolism-related in-hospital death or adverse outcomes. There was no difference in the prognosis of patients with PAST according to the administration of anticoagulation. PAST was rarely detected in lung cancer patients on follow-up chest computed tomography after lung resection. Patients with PAST were asymptomatic in most cases and had relatively favorable clinical outcomes. However, these patients are at risk of contralateral PE, despite its rarity.

Risk stratification is important for the management of community-acquired pneumonia (CAP). The present study aimed to investigate the clinical impact of N-terminal prohormone of brain natriuretic peptide (NT-proBNP) on prognosis and to identify clinical characteristics associated with NT-proBNP elevation in CAP patients.

The etiology of pleural effusions often remained unknown notwithstanding surgical pleural biopsy and further clinical observation. A better understanding of clinical characteristics of patients with idiopathic pleural effusion (IPE) may improve the ability to differentiate between IPEs and cytology-negative malignant pleural effusions (MPEs) and facilitate the identification of patients requiring invasive investigation. However, little is known about the clinical factors that can help distinguish patients with IPE from those with cytology-negative MPE.

Data regarding the radiological and clinical features of pulmonary tuberculosis (PTB) in patients with idiopathic pulmonary fibrosis (IPF) are limited. Accordingly, the aim of this study was to investigate the clinico-radiological features of PTB in patients with IPF.

Malignant pleural effusion (MPE) occasionally demonstrates neutrophilic predominance, commonly found in parapneumonic pleural effusion (PPE). In comparison with lymphocytic MPE, neutrophilic MPE may have different characteristics associated with a more intense inflammatory response and poor prognosis. These characteristics of neutrophilic MPE may lead to inappropriate management and delayed diagnosis. Moreover, the limited diagnostic yield of microbiologic and cytologic tests makes early differential diagnosis between neutrophilic MPE and PPE more challenging. This study investigated objective laboratory findings to help distinguish neutrophilic MPE from PPE.

Data on the relationship between the clinical and microbiological features of community-acquired pneumonia (CAP) and its computed tomography (CT) findings are limited. The aim of the present study was to investigate the clinic-microbiological features of patients with CAP presenting with ground-glass opacity (GGO) and centrilobular nodules or tree-in-bud pattern on CT images.

Non-expandable lung (NEL) often occurs during pleural fluid drainage in patients with malignant pleural effusion (MPE). However, data regarding the predictors and prognostic impact of NEL on primary lung cancer patients with MPE receiving pleural fluid drainage, compared to malignant pleural mesothelioma (MPM), are limited. This study was aimed to investigate the clinical characteristics of lung cancer patients with MPE developing NEL following ultrasonography (USG)-guided percutaneous catheter drainage (PCD) and compare the clinical outcomes between those with and without NEL. Clinical, laboratory, pleural fluid, and radiologic data and survival outcomes of lung cancer patients with MPE undergoing USG-guided PCD were retrospectively reviewed and compared between those with and without NEL. Among 121 primary lung cancer patients with MPE undergoing PCD, NEL occurred in 25 (21%). Higher pleural fluid lactate dehydrogenase (LDH) levels and presence of endobronchial lesions were associated with development of NEL. The median time to catheter removal was significantly extended in those with NEL compared to those without (P= .014). NEL was significantly associated with poor survival outcome in lung cancer patients with MPE undergoing PCD, along with poor Eastern Cooperative Oncology Group (ECOG) performance status (PS), the presence of distant metastasis, higher serum C-reactive protein (CRP) levels, and not receiving chemotherapy. NEL developed in one-fifth of lung cancer patients undergoing PCD for MPE and was associated with high pleural fluid LDH levels and the presence of endobronchial lesions. NEL may negatively affect overall survival in lung cancer patients with MPE receiving PCD.

Patients with cancer are at an increased risk of tuberculosis. As pleural effusion has great clinical significance in patients with cancer, the differential diagnosis between tuberculous pleural effusion (TPE) and malignant pleural effusion (MPE) is important. However, the predictive factors and treatment outcomes of TPE in patients with cancer have rarely been studied.

Data regarding coexisting pulmonary thromboembolism (PTE) in patients with tuberculosis are limited. The aim of this study was to investigate the clinical features of coexisting PTE in patients with respiratory tuberculosis.

: Computed tomography (CT) is the mainstay imaging modality for suspected pleural malignancy. Tuberculous pleural effusion (TPE) can present with various pleural abnormalities. However, few studies have evaluated the different characteristics of pleural abnormalities on chest CT between TPE and malignant pleural effusion (MPE).

Data regarding the clinical characteristics and treatment outcomes of patients with community-acquired pneumonia (CAP) and bronchiectasis (BE) are rare. This study aims to elucidate the clinical relevance of BE in patients with CAP.

Although pneumonia is associated with an increased risk of venous thromboembolism, patients with pulmonary embolism and concomitant pneumonia are uncommon. The aim of the present study was to investigate the clinical features of pulmonary embolism with coexisting pneumonia. We retrospectively compared clinical, radiologic and laboratory parameters between patients with pulmonary embolism and concomitant pneumonia (pneumonia group) and those with unprovoked pulmonary embolism (unprovoked group), and then between the pneumonia group and those with pulmonary infarction (infarction group). Of 794 patients with pulmonary embolism, 36 (5%) had coexisting pneumonia and six (1%) had no provoking factor other than pneumonia. Stroke was significantly more common in the pneumonia group, than either the unprovoked group or the infarction group. In the pneumonia group, fever was significantly more common and serum C-reactive protein levels were significantly higher. By contrast, central pulmonary embolism and right ventricular dilation on computed tomography were significantly less frequent in the pneumonia group. In addition, an adverse outcome due to pulmonary embolism was less common in the pneumonia group than in either of the other two groups. The coexistence of pulmonary embolism and pneumonia is rarely encountered in clinical practice, especially without the presence of other factors that could provoke venous thromboembolism and is commonly associated with stroke. It is characterized by lower incidences of central pulmonary embolism and right ventricular dilation and by a lower rate of adverse outcomes due to pulmonary embolism itself.

There are limited data on the rate of clot resolution after acute pulmonary embolism and risk factors for residual emboli. The aim of the present study was to investigate the rate of clot resolution over time and identify risk factors of residual emboli in pulmonary embolism patients. We retrospectively analyzed pulmonary embolism patients with follow-up computed tomography (CT) scans taken between day 3 and day 90. The patients were classified into three cohorts, depending on the time of CT scan: day 3–7, day 8–21, and day 22–90. Each cohort was regrouped into the residual embolus and complete resolution groups. The rate of complete resolution of pulmonary emboli was 24% at 3–7 days, 47% at 8–21 days, and 78% at 22–90 days. In a multivariate analysis, independent predictors in each cohort were lobar or larger pulmonary artery pulmonary embolism and a right ventricle/left ventricle diameter ratio within 1 week, lobar or larger pulmonary artery pulmonary embolism at 1–3 weeks, and central pulmonary embolism at 3 weeks to 3 months. The rate of venous thromboembolism (VTE) recurrence, frequency of an adverse outcome, and in-hospital mortality did not differ between the two groups in each cohort. Complete resolution of pulmonary emboli occurred in most pulmonary embolism patients. Regardless of the time interval, larger pulmonary artery involvement by pulmonary emboli was only independent predictor of residual emboli. The presence of residual emboli was not associated with an adverse outcome of pulmonary embolism and rate of VTE recurrence.

Tuberculous pleural effusion (TPE) is generally characterized by lymphocytic exudative effusion, either free-flowing or loculated. However, patients can also have neutrophilic loculated TPE, although little data are available concerning the incidence and characteristics of this form of TPE. It is important to differentiate between neutrophilic loculated TPE and complicated parapneumonic effusion (PPE), which also shows neutrophilic loculated effusion but needs a different management approach. The present study evaluated the incidence and characteristics of neutrophilic loculated TPE and differentiated it from complicated PPE.

Little is known regarding the clinical features and course of in-situ pulmonary artery thrombosis (PAT). The aim of the present study was to investigate the clinical characteristics of PAT. Patients with PAT were retrospectively identified from a tertiary referral center in South Korea. A control group consisted of patients with pulmonary embolism in whom the right or left pulmonary artery was the largest pulmonary embolism-involved site. We compared various clinical parameters between the two groups. Of the 23 PAT patients, the most common underlying condition was tuberculosis-destroyed lung [11 (47.8%)], followed by pulmonary artery stump after lobectomy or pneumonectomy [7 (30.4%)]. In all patients except one, PAT was located in the right or left pulmonary artery. Computed tomography scans demonstrated that clots were completely or partially resolved less frequently in the PAT group than in the control group [4 (25%) versus 62 (90%); P < 0.001]. In the PAT group, three of the seven patients (43%) who had undergone anticoagulation therapy exhibited improvement, and one of the nine patients (11%) who had not received anticoagulation therapy experienced improvement; however, the difference was not significant. Tuberculosis-destroyed lung was the most common underlying condition in Korean PAT patients, followed by pulmonary artery stump after lung resection. The clots in patients with PAT were mostly located in the right or left pulmonary artery, and clot resolution was less frequent in the PAT group compared to the pulmonary embolism group.

Differential leukocyte counts of pleural fluid are routinely recommended for the early diagnosis and management of exudative pleural effusions. Rapid automated cellular analysis agrees strongly with standard manual microscopic counts and has become a reality in many clinical laboratories. However, discordant results sometimes observed between automated and manual analyses raise concern about using automated analysis to aid prompt differential diagnosis. This study aimed to evaluate the real-world disagreement between automated and manual leukocyte analyses in exudative pleural effusions and to investigate whether the discordant results occur in specific cellular ranges or randomly. We conducted a retrospective study of patients who were diagnosed with parapneumonic pleural effusions (PPE), tuberculous pleural effusions (TPE), and malignant pleural effusions (MPE) between September 2018 and December 2020. Differential and predominant leukocyte counts were performed using an automated XN-350 analyzer with a two-part differential count consisting of polymorphonuclear (PMN) and mononuclear (MN) leukocytes and a manual method with Wright-stained cytospin slides. We compared the two methods on cases of 109 PPEs, 50 TPEs, and 116 MPEs. Although the overall correlation between the two methods for differential leukocyte counts was excellent, there were etiologic variations; MPEs showed a lower correlation compared to PPEs and TPEs. Automated-PMN predominance almost corresponded to manual cytospin-neutrophilic predominance. In contrast, ~10% of the automated-MN predominance did not correspond with the cytospin-lymphocytic predominance. These discrepancies occurred most in the automated-MN% range of 51% to 60%, followed by 61% to 70%. The PMN% range ≥50% and <30% on the automated analysis reliably corresponds to the neutrophilic and lymphocytic predominance, respectively. However, the MN% range of 51% to 70% may not coincide with lymphocytic predominance on manual cytospin analysis. This range leaves the potential cause of exudative pleural effusions open.

AbstractCholedochal cysts are congenital anomalies of the biliary tract manifested by cystic dilatation of the extrahepatic and intrahepatic bile ducts. Choledochal cyst is not rare in far-East Asian countries. Type II choledochal cysts account for 2 of all such cysts. They are true diverticula of the extrahepatic bile duct and communicate with the bile duct through a narrow stalk. This condition is associated with significant complications, such as ductal strictures, stone formation, cholangitis, rupture and secondary biliary cirrhosis. We describe a case of a huge impacted stone in a diverticular choledochal cyst which masqueraded as an unusual cystic duct stone causing Mirizzi's syndrome.Copyright © 2013 S. Karger AG, Basel

AbstractA 70-year-old man had undergone pancreaticoduodenectomy due to a distal common bile duct malignancy. After the operation, serous fluid discharge decreased from two drain tubes in the retroperitoneum. Over four weeks, the appearance of the serous fluid changed to a greenish bile color and the patient persistently drained over 300 ml/day. Viewed as bile leak at the choledochojejunostomy, treatment called for endoscopic diagnosis and therapy. Cap-fitted forward-viewing endoscopy demonstrated that the distal tip of a pancreatic drain catheter inserted at the pancreaticojejunostomy site had penetrated the opposite jejunum wall. One of the drain tubes primarily placed in the retroperitoneum had also penetrated the jejunum wall, with the distal tip positioned near the choledochojejunostomy site. No leak of contrast appeared beyond the jejunum or anastomosis site. Following repositioning of a penetrating catheter of the pancreaticojejunostomy, four days later, the patient underwent removal of two drain tubes without additional complications. In conclusion, the distal tip of the catheter, placed to drain pancreatic juice, penetrated the jejunum wall and may have caused localized perijejunal inflammation. The other drain tube, placed in the retroperitoneal space, might then have penetrated the inflamed wall of the jejunum, allowing persistent bile drainage via the drain tube. The results masqueraded as bile leakage following pancreaticoduodenectomy.Copyright © 2011 S. Karger AG, Basel

A dye‐sensitized solar cell (DSSC) containing a TiO2film treated with COOH‐functionalized germanium nanoparticles (GeCOOH Nps) exhibited a higher short‐circuit photocurrent density (Jsc; 15.4 mA cm−2) compared to the corresponding untreated DSSC (13.4 mA cm−2) using N719 and a 12 μm thick TiO2film at 100 mW cm−2. The amount of N719 attached to the treated TiO2film was 21 % greater than that attached to the untreated TiO2film. Enhancement of the Jscvalue by 15 % was attributed mostly to an intramolecular charge transfer from N719 attached to the GeCOOH Nps to the TiO2conduction band through the GeCOOH Nps.

In the recent development of internal combustion engine, considerable increase in speed and power has been accomplished. This achievement, however, brought up various problems due to the excessive temperature of engine parts, which becomes a crucial factor in engine durability. In the present paper, temperature measurement of a marine engine was investigated experimentally. The adapter is made to pull out a thermocouple through the safety valve hole of the engine. The thermocouple is welded on the surface of the cylinder cover to measure the average temperatures of the engine cylinder cover. Ceramic adhesive was used for preventing the affect of high temperature combustion gas. The cylinder cover temperatures of the engine were measured by means of surface welding method. As a result, average temperatures of the engine cylinder cover were successfully in the range of 85~335oC. In the present study, the surface welding method was confirmed from the temperature measurement of cylinder cover in an experimental engine, and can be applied to large-sized marine engine without damage.

A series of donor–π–donor derivatives containing phenyl, naphthyl, and anthryl groups as the π‐center and heterocyclic rings as the conjugation bridge have been synthesized and their one‐ and two‐photon spectroscopic properties and photostability were determined. These compounds show bathochromic shifts in the absorption and emission spectra, larger two‐photon cross‐section, and enhanced photostability in comparison to their open‐chain analogues. In addition, a convenient method for the qualitative photostability measurement is proposed.

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DNA repair plays a critical role in protecting the genome from insults of cancer-causing agents, such as those found in tobacco smoke. Therefore, reduced DNA repair capacity can increase the susceptibility to smoking-related cancers. Recently, several polymorphisms have been identified in the xeroderma pigmentosum group G (XPG) gene, and it is possible that these polymorphisms may affect the DNA repair capacity, thereby modulating cancer susceptibility. We investigated the relationship between the His1104Asp polymorphism in the XPG gene and the risk of lung cancer. The study population consisted of 310 lung cancer patients and 311 healthy controls who were frequency (1:1) matched based on age and sex. The Asp/Asp genotype was more frequent in the controls (28.9%) than in the cases (18.7%) and associated with a significantly decreased risk of lung cancer [adjusted odds ratio (OR) = 0.54, 95% confidence interval (CI) = 0.37-0.80] when the combined His/His and His/Asp genotype was used as the reference. The protective effect of the Asp/Asp genotype against lung cancer was statistically significant in the older subjects (adjusted OR = 0.51, 95% CI = 0.37-0.80), males (adjusted OR = 0.54, 95% CI = 0.35-0.83), and lighter smokers (adjusted OR = 0.48, 95% CI = 0.25-0.94) in a stratification analysis. When the lung cancers were analyzed by histologic type, the Asp/Asp genotype was associated with a significantly decreased risk of squamous cell carcinoma (adjusted OR = 0.55, 95% CI = 0.34-0.88) and small cell lung cancer (adjusted OR = 0.44, 95% CI = 0.20-0.97), but non-significant decreased risk of adenocarcinoma (adjusted OR = 0.64, 95% CI = 0.36-1.12). These results suggest that the XPG codon 1104 polymorphism contributes to genetic susceptibility to lung cancer.

Abstract: This work deals with the electrical conductivity of dielectric and cobalt percentage on output parameters such as metal removal rate and surface roughness value of sintered carbides cut by wire-electrical discharge machining (WEDM). To obtain a precise workpiece with good quality, some extra repetitive finish cuts along the rough cutting contour are necessary. Experimental results show that increases of cobalt amount in carbides affects the metal removal rate and worsens the surface quality as a greater quantity of solidified metal deposits on the eroded surface. Lower electrical conductivity of the dielectric results in a higher metal removal rate as the gap between wire electrode and workpiece reduced. Especially, the surface characteristics of rough-cut workpiece and wire electrode were analyzed too. To obtain a good surface equality without crack, 4 finish-cuts were necessary by reducing the electrical energy and the offset value.

In order to obtain high productivity of clavulanic acid, a newly-introduced carrier, polyurethane pellet (PUP) Z97-020 was used for the immobilization process. In a stirred-tank bioreactor, batch cultivation by Streptomyces clavuligerusKK immobilized on PUP Z97-020 gave about 3100 mg of clavulanic acid per litre, representing an increase of 200% in productivity compared with that by fed-batch cultivation of free cells (1500 mg/l). However, the clavulanic acid produced rapidly decomposed due to the pH change during batch cultivation. Fed-batch cultivation by immobilized S. clavuligerusKK gave an excellent level of clavulanic acid up to 3250 mg/l, a productivity increase of 220% compared with that by fed-batch cultivation of free cells. These results suggest that immobilization with PUP Z97-020 is a more effective process for the production of clavulanic acid and that the maintenance of pH by fed-batch cultivation with glycerol as a limiting substrate prevents the clavulanic acid from decomposing during the fermentation.

The objective of this study was to investigate the effects of nutrients and culture conditions on morphology during the seed culture ofC. acremoniumATCC 20339. Morphological factors such as hyphal length, number of tips, number of arthrospores were observed to investigate the relationship between seed morphology and CPC production. During the time course of seed culture, hyphal length was shortened and the number of arthrospores increased rapidly. On the other hand, the number of tips decreased rapidly, and this was closely related to the hyphal length. Mixed nitrogen sources of 3% soybean meal and 1% cotton seed flour were determined as the proper organic nitrogen sources, in terms of the morphological factors in the seed culture. This fact was proven in batch culture for the production of Cephalosporin C. It was also found that a proper agitation speed enhanced the morphological differentiation ofC. acremoniumATCC 20339, thus improving the production of Cephalosporin C.

A technique for complete urinary diversion was used in the management of urinary fistula following renal transplantation. Nephrostomy was modified by closing the renal pelvis at the ureteropelvic junction. No impairment of renal function occurred. In the presence of infection, it is reasonable first to treat the infection and postpone the reconstructive procedure until the infection has subsided.

Test results are presented for nine annular seals which use a roughened stator and smooth rotor to yield an increase in net damping as compared to conventional smooth-rotor / smooth-stator annular seals. Round-hole roughness patterns are used to achieve the desired stator roughness. The results presented demonstrate that the maximum net damping is achieved by (a) a hole pattern which takes up about 34 percent of the surface area, and (b) hole depths which are about three times the radial clearances. When compared to a smooth seal, the optimum configuration increases net damping by 37 percent, while reducing leakage by 46 percent and direct stiffness by 23 percent. Comparisons of experiment to theory are generally satisfactory for hole-patterns near the optimum area ratio of 34 percent. However, the theory is unsatisfactory for seals which have a substantially higher percentage of the surface area taken up by holes.

An analysis for helically-grooved turbulent annular seals is developed to predict leakage and dynamic coefficients, as related to rotordynamics. The grooved surface pattern is formulated as an inhomogeneous directivity in surface shear stress. The governing equations, based on both Hirs’ turbulent lubrication theory and “fine-groove” theory, are expanded in the eccentricity ratio to yield zeroth and first-order perturbation solutions. The zeroth-order equations define the steady-state leakage and the circumferential velocity development due to wall shear for a centered rotor position. The first-order equations define perturbations in the pressure and axial and circumferential velocity fields due to small motion of the rotor about the centered position. Numerical results are presented for proposed grooved seals in the High Pressure Oxygen Turbopump (HPOTP) of the Space Shuttle Main Engine (SSME) and for a water-pump application. The results show that an optimum helix angle exists from a rotordynamic stability viewpoint. Further, a properly designed helically-grooved stator is predicted to have pronounced stability advantages over other currently used seals.

A combined analytical-computational method is developed to calculate the transient pressure field and dynamic coefficients for high-pressure annular seal configurations which may be used in interstage and neck-ring seals of multistage centrifugal pumps. The solution procedure applies to constant-clearance or convergent-tapered geometries which may have different (but directionally-homogeneous) surface-roughness treatments on the stator or rotor seal elements. It applies in particular so-called “damper-seals” which employ smooth rotors and deliberately-roughened stator elements to enhance rotor stability. Hirs’ turbulent lubrication equations are modified slightly to account for different surface-roughness conditions on the rotor and stator. A perturbation analysis is employed in the eccentricity ratio to develop zeroth and first order perturbation equations. The zeroth-order equations define both the leakage and the development of circumferential flow due to shear forces at the rotor and stator surfaces. The first-order equations define perturbations in the pressure and axial and circumferential velocity fields due to small relative motion between the seal rotor and stator. The solution applies for small motion about a centered position and does not employ linearization with respect to either the taper angle or the degree of swirl, i.e., the difference between the circumferential velocity at the given axial position and the asymptotic circumferential-velocity solution. Test results for four different surface-roughness confirm the predicted net damping increase for “damper seals.” A round-hole-pattern stator yielded the highest net damping and lowest leakage of all seals tested. The seals are substantially stiffer than predicted, but the theory does an adequate job of predicting net damping.

This study examined the rate of binocular photophobia in intermittent exotropia patients before surgical correction, and the factors affecting this rate. The study also investigated the factors affecting postsurgical disappearance of binocular photophobia.

The minority carrier lifetime of single crystalline Si increases by the formation of an ultrathin silicon dioxide (SiO2) layer by use of the nitric acid oxidation of Si (NAOS) method. With the NAOS method using 68 or 98 wt% HNO3solutions, large increases in the lifetime are observed while the enhancement of the lifetime is low for the 40 wt% HNO3NAOS method. In the case of the hydrogen-terminated Si surfaces formed by hydrofluoric acid (HF) treatment, the initial minority carrier lifetime is high, but it returns to the value before the HF treatment by keeping in air for 5 days. In the case of the NAOS method, on the other hand, the enhanced lifetime remains unchanged with time kept in air. This stability is attributed to high atomic density of the NAOS SiO2layer which prevents diffusion of oxidizing species. The atomic density of the NAOS SiO2layer increases with the HNO3concentration, which leads to an increase in the valence band discontinuity energy at the SiO2/Si interface. When the NAOS SiO2layer is inserted between the Si substrate and a silicon nitride anti-reflection layer for n-Si-based pn-junction solar cells, the conversion efficiency is increased from 17.2 to 18.9%. The internal quantum efficiency in the short wavelength region (300∼600 nm) is improved by the NAOS SiO2layer, indicating the front surface is effectively passivated by the NAOS SiO2layer.

The paper presents the dynamic analysis of an anisotropic rotor system with fluid interaction by using modal nonsynchronous perturbation testing and dynamic stiffness approaches. The anisotropic rotor system produces more complex rotor behavior than an isotropic system. In particular, the existence of the quadrature resonance phenomenon for backward precession is demonstrated. A symmetric rotor supported anisotropically by one fluid lubricated bearing and one rolling element bearing simulates rotating machinery behavior. A dynamic stiffness anisotropy algorithm which includes fluid terms is used to process experimental data in order to identify lightly loaded journal fluid film force parameters. The existence of the quadrature resonance for backward precession obtained from the experiment is compared with the analytical model. The results from modeling show strong agreement with experimental results.