Real-time sample analysis using a sampling probe and miniature mass spectrometer.

A miniature mass spectrometry system with a sampling probe has been developed for real-time analysis of chemicals from sample surfaces. The sampling probe is 1.5 m in length and is comprised of one channel for introducing the spray and the other channel for transferring the charged species back to the Mini MS. This system provides a solution to the problem of real-time mass spectrometry analysis of a three-dimensional object in the field and is successful with compounds including those in inks, agrochemicals, explosives, and animal tissues. This system can be implemented in the form of a backpack MS with a sampling probe for forensic analysis or in the form of a compact MS with an intrasurgical probe for tissue analysis.

Reduction of global 5-hydroxymethylcytosine is a poor prognostic factor in breast cancer patients, especially for an ER/PR-negative subtype.

DNA methylation at the 5 position of cytosine (5 mC) is an epigenetic hallmark in cancer. The 5 mC can be converted to 5-hydroxymethylcytosine (5 hmC) through a ten-eleven-translocation (TET). We investigated the impact of 5 mC, 5 hmC, TET1, and TET2 on tumorigenesis and prognosis of breast cancer. Immunohistochemistry was used to assess the levels of 5 mC, 5 hmC, TET1, and TET2 in the corresponding tumor adjacent normal (n = 309), ductal carcinoma in situ (DCIS, n = 120), and invasive ductal carcinoma (IDC, n = 309) tissues for 309 breast ductal carcinoma patients. 5 mC, 5 hmC, TET1-n, and TET2-n were significantly decreased during DCIS and IDC progression. In IDC, the decrease of 5 hmC was correlated with the cytoplasmic mislocalization of TET1 (p < 0.001) as well as poor disease-specific survival (DSS) (adjusted hazard ratio [AHR] 1.95, p = 0.003) and disease-free survival (DFS) (AHR 1.91, p = 0.006). The combined decrease of 5 mC and 5 hmC was correlated with worse DSS (AHR 2.19, p = 0.008) and DFS (AHR 1.99, p = 0.036). Stratification analysis revealed that the low level of 5 mC was associated with poor DSS (AHR 1.89, p = 0.044) and DFS (AHR 2.02, p = 0.035) for the ER/PR-positive subtype. Conversely, the low level of 5 hmC was associated with worse DSS (AHR 2.77, p = 0.002) and DFS (AHR 2.69, p = 0.006) for the ER/PR-negative subtype. The decreases of 5 mC, 5 hmC, TET1-n, and TET2-n were biomarkers of tumor development. The global reduction of 5 hmC was a poor prognostic factor for IDC, especially for ER/PR-negative subtype.

A randomized trial comparing concurrent chemoradiotherapy with single-agent cisplatin versus cisplatin plus gemcitabine in patients with advanced cervical cancer: An Asian Gynecologic Oncology Group study.

OBJECTIVE: A recent randomized trial demonstrated that concurrent chemoradiotherapy (CCRT) with weekly cisplatin and gemcitabine, followed by two adjuvant cycles of cisplatin and gemcitabine improved survival for advanced cervical cancer patients. An Asian Gynecologic Oncology Group (AGOG) study was designed to determine whether only adding gemcitabine in the chemoradiation phase without adjuvant chemotherapy could improve survival. METHODS: Between March 2009 and March 2013, 74 eligible patients with International Federation of Obstetrics and Gynecology stage III/IVA cervical cancer or stage I/II with positive pelvic/para-aortic nodal metastasis were enrolled. Thirty-seven patients were randomized to arm C (weekly cisplatin 40mg/m(2)) and 37 patients were randomized to arm CG (weekly cisplatin 40mg/m(2) and gemcitabine 125mg/m(2)), for six cycles. Six eligible patients were excluded before the beginning of treatment. RESULTS: An interim analysis showed superimposable progression-free (PFS) and overall survival (OS), a decision of closing accrual was made. A 3-year PFS was similar in both arms (arm C 65.1% vs. arm CG 71.0%, p=0.71), and a 3-year OS was 74.1% in arm C vs. 85.9% in arm CG (p=0.89), but crossed over at 5years. Grade 2-4 hematological toxicities, including neutropenia (p=0.028) and thrombocytopenia (p=0.001), were more frequent in arm CG than arm C. CONCLUSIONS: Despite limitation in power, it suggests that only adding gemcitabine at the CCRT phase does not provide substantially superior results, but treatment toxicities could increase. Further studies are required to determine the role of post-CCRT adjuvant chemotherapy in advanced cervical cancer.

Change of scaling-induced proinflammatory cytokine on the clinical efficacy of periodontitis treatment.

Proinflammatory cytokines are key inflammatory mediators in periodontitis. This study aimed to investigate the relationship between proinflammatory cytokines in saliva and periodontal status. To investigate the usefulness of cytokines in the therapeutic approach for periodontal disease, the relationship between stimulated cytokine changes and the periodontitis treatment outcome was investigated in this study. Saliva was obtained from 22 patients diagnosed by dentists as having chronic periodontitis. The proinflammatory cytokine (interleukin-1α (IL-1α), interleukin-1ß (IL-1ß), interleukin-6 (IL-6), interleukin-8 (IL-8), tumor necrosis factor α (TNF-α), and tumor necrosis factor ß (TNF-ß)) levels were determined using a commercially available kit. The IL-1ß and IL-6 levels increased, whereas the TNF-ß levels decreased with the severity of periodontitis (4 mm pocket percentage). Poststimulation IL-1α, IL-6, and IL-8 levels were higher in patients who had an improved treatment outcome. The differences of IL-6 levels (cut point: 0.05 µg/g) yielded a sensitivity and specificity of 90.0% and 81.82%, respectively, for predicting the periodontitis treatment outcome. Among the proinflammatory cytokines, stimulated IL-6 was an excellent marker for predicting the periodontitis treatment outcome.

Autonomous in situ analysis and real-time chemical detection using a backpack miniature mass spectrometer: concept, instrumentation development, and performance.

A major design objective of portable mass spectrometers is the ability to perform in situ chemical analysis on target samples in their native states in the undisturbed environment. The miniature instrument described here is fully contained in a wearable backpack (10 kg) with a geometry-independent low-temperature plasma (LTP) ion source integrated into a hand-held head unit (2 kg) to allow direct surface sampling and analysis. Detection of chemical warfare agent (CWA) simulants, illicit drugs, and explosives is demonstrated at nanogram levels directly from surfaces in near real time including those that have complex geometries, those that are heat-sensitive, and those bearing complex sample matrices. The instrument consumes an average of 65 W of power and can be operated autonomously under battery power for ca. 1.5 h, including the initial pump-down of the manifold. The maximum mass-to-charge ratio is 925 Th with mass resolution of 1-2 amu full width at half-maximun (fwhm) across the mass range. Multiple stages of tandem analysis can be performed to identify individual compounds in complex mixtures. Both positive and negative ion modes are available. A graphical user interface (GUI) is available for novice users to facilitate data acquisition and real-time spectral matching.

Scaling-stimulated salivary antioxidant changes and oral-health behavior in an evaluation of periodontal treatment outcomes.

AIM: Our goal was to investigate associations among scaling-stimulated changes in salivary antioxidants, oral-health-related behaviors and attitudes, and periodontal treatment outcomes. MATERIALS AND METHODS: Thirty periodontitis patients with at least 6 pockets with pocket depths of >5 mm and more than 16 functional teeth were enrolled in the study. Patients were divided into three groups: an abandoned group (AB group), a nonprogress outcome group (NP group), and an effective treatment group (ET group). Nonstimulated saliva was collected before and after scaling were received to determine superoxide dismutase (SOD) and the total antioxidant capacity (TAOC). RESULTS: Salivary SOD following scaling significantly increased from 83.09 to 194.30 U/g protein in patients who had irregular dental visit patterns (<1 visit per year). After scaling, the TAOC was significantly higher in patients who had regular dental visits than in patients who had irregular dental visits (3.52 versus 0.70 mmole/g protein, P < 0.01). The scaling-stimulated increase in SOD was related to a higher severity of periodontitis in the NP group, while the scaling-stimulated increase in the TAOC was inversely related to the severity of periodontitis in the AB group. CONCLUSIONS: These results demonstrate the importance of scaling-stimulated salivary antioxidants as prognostic biomarkers of periodontal treatment.

Development of a mass spectrometry sampling probe for chemical analysis in surgical and endoscopic procedures.

A sampling probe based on ambient desorption ionization was designed for in vivo chemical analysis by mass spectrometry in surgical and endoscopic procedures. Sampling ionization of analytes directly from tissue was achieved by sealing the sampling tip against the tissue surface without allowing leakage of the auxiliary gas used for desorption ionization. The desorbed charged species were transferred over a long distance (up to 4 m) through a flexible tube of internal diameter as small as 1/16 in. to the inlet of the mass spectrometer used for analysis. The conditions used for desorption electrospray ionization (DESI) were optimized to achieve biocompatibility for clinical applications while obtaining adequate efficiency for the analysis. This optimization involved the removal of high voltage and use of pure water as a spray solvent instead of the organic solvents or aqueous mixtures normally used. Improved sensitivity was achieved under these conditions by increasing the gas flow rate in the transfer tube. The destructive effect on tissue surfaces associated with typical desorption ionization was avoided by altering the local gas dynamics in the sample area without compromising the overall analysis efficiency.

Ultrasound-guided foam sclerotherapy for treating incompetent great saphenous veins--results of 5 years of analysis and morphologic evolvement study.

BACKGROUND: Varicose veins of the lower leg is a common disease and is associated with long-term morbidity. It has been treated using high ligation with stripping and endovenous laser surgery of the great saphenous vein (GSV). OBJECTIVES: To investigate the clinical outcomes of GSV insufficiency after ultrasound-guided foam sclerotherapy (UGFS) using 3% sodium tetradecyl sulfate (STS). METHODS: Between 2005 and 2009, patients with symptomatic varicose veins secondary to GSV insufficiency were enrolled; 3% STS foam was injected into the GSV under ultrasound visualization. Ultrasound examinations and clinical follow-up were performed at 3- to 6-month intervals. Follow-up visits continued through April 2011. RESULTS: Two hundred 88 limbs of 233 patients were enrolled. The mean follow-up interval was 37.8 months. Occlusion was achieved for 89.6% of the incompetent veins in two sessions of UGFS. The mean number of therapy sessions per leg was 1.53. The internal diameters of the treated veins reduced to 66.9% 3 months and 32.7% at 12 months. CONCLUSIONS: UGFS is effective in sealing incompetent GSV segments. It is a minimally invasive procedure and can be redone several times in cases of recurrence. UGFS is simpler and less painful than stripping surgery and endovenous laser treatment.

Impact of intracranial extension on survival in stage IV nasopharyngeal carcinoma: identification of a subset of patients with better prognosis.

OBJECTIVE: T-stage is an imperfect prognostic indicator for patients with nasopharyngeal carcinoma. We evaluated the effect of extent of intracranial involvement on survival after conventional radiotherapy in patients with Stage T4 nasopharyngeal carcinoma. METHODS: We conducted a retrospective analysis of the results of computed tomography, magnetic resonance imaging and treatment outcomes in 84 consecutive patients with Stage T4 nasopharyngeal carcinoma during the period September 1993 to December 2002 in Taiwan. The patients were subcategorized into those who had limited intracranial involvement (primary nasopharyngeal tumors with involvement of the unilateral cavernous sinus or the parasellar region only) or extensive involvement (extension of the tumors to the bilateral cavernous sinus or the parasellar region, into the orbit and the ethmoid sinus anteriorly, or to the prepontine region and the posterior cranial fossa). RESULTS: Extensive intracranial involvement was found in 51.2% of the patients. Among these patients, the 5-year rate of overall survival after conventional radiotherapy was only 3.4%. In contrast, the 5-year survival among patients with limited intracranial involvement was 42.9%. This difference was significant (P < 0.001). In the multivariate analysis, extensive intracranial involvement, advanced age and a nodal status of N3 correlated with poor overall survival (all P < 0.05). CONCLUSIONS: Among patients with T4 nasopharyngeal carcinoma, better treatment outcomes were associated with limited intracranial involvement. We conclude that a subdivision of Stage T4 nasopharyngeal carcinoma disease based on the extent of intracranial involvement would provide better prognostic information.

MALDI ion trap mass spectrometer with charge detector for large biomolecule detection.

Up to now, all commercial matrix-assisted laser desorption/ionization (MALDI) mass spectrometers still can not efficiently analyze very large biomolecules. In this work, we report the development of a novel MALDI ion trap mass spectrometer which can enrich biomolecular ions to enhance the detection sensitivity. A charge detector was installed to measure the large ions directly. With this design, we report the first measurement of IgM with the mass-to-charge ratio (m/z) at 980 000. In addition, quantitative measurements of the number of ions can be obtained. A step function frequency scan was first developed to get a clear signal in the m/z range from 200,000 to 1,000,000.

Reduction in osmidrosis using a suction-assisted cartilage shaver improves the quality of life.

BACKGROUND: Axillary osmidrosis is a benign disorder that causes functional and emotional problems in Asian patients. Surgical treatments have proven effective in treating this disease, but changes in quality of life after surgical procedures have not been investigated so far. OBJECTIVE: To evaluate quality of life in patients with osmidrosis before and after surgery with suction-assisted cartilage shaver using the Dermatology Life Quality Index (DLQI). METHODS: Seventy patients with axillary osmidrosis (aged 14-49, 8 men and 62 women) who were treated using a suction-assisted cartilage shaver at the Department of Dermatology, Chang Gung Memorial Hospital, from May 2006 to November 2008 were included. Patients completed the DLQI before and 6 to 35 (mean 18.3) months after treatment. Scores for patient satisfaction and improvement were also investigated. RESULTS: Mean DLQI score before treatment was 11.3 (range 5-27). After 6 to 35 (mean 18.3) months of postoperative follow-up, DLQI scores (mean 0.8, range 0-4) declined significantly (93% reduction). Fifty-nine patients (84.2%) reported odor reduction of 90% or more; 24 patients (34.3%) were greatly satisfied, and 41 were (58.6%) absolutely satisfied with this procedure. CONCLUSION: Our data demonstrate that the suction-assisted cartilage shaver can greatly improve functional and social disabilities in patients with axillary osmidrosis. The authors have indicated no significant interest with commercial supporters.

Assessing the endocrine disrupting potentials and genotoxicity in environmental samples from Taiwanese rivers.

BACKGROUND: Surface waters receive a variety of organic pollutants via wastewater discharge, and sediment represents a sink for hydrophobic contaminants. In this study, we used in vitro yeast-based reporter gene assays and a Bacillus subtilis Rec-assay to examine the occurrence of endocrine disrupting activities and genotoxic potentials in samples collected from three Taiwanese rivers. Levels of 51 polycyclic aromatic hydrocarbons (PAHs) in muscles of fish captured from same rivers were also analyzed to assess in vivo pollution of PAHs. RESULTS: Antagonist activities for androgen receptor and retinoid X receptor (RXR) were detected in river water extracts at environmentally relevant concentrations., and sediment extracts exhibited RXR agonist, RXR antagonist, and genotoxic potentials concurrently. Σ16 PAHs in fish muscles ranged from 44.9-242.4 ng g- 1 dry weight, representing 38 to 59% of the total 51 PAHs concentrations, and methylated PAHs of low molecular weight PAHs were often detected as well. CONCLUSION: Taiwanese river sediment samples concomitantly exhibited RXR disrupting potentials and genotoxic activities, whereas RXR agonist and antagonist activities were simultaneously detected in several dry-season sediment extracts. PAH levels in fish muscles were categorized as minimally polluted by aromatic compounds, nonetheless, the presence of methylated PAHs in muscles samples may be of concern owing to the higher toxic potentials than their parent compounds.

Metastasis of mediastinal epithelioid angiosarcoma to the finger.

Epithelioid angiosarcoma (EA) is a rare malignant, vascular tumor that is usually observed in middle-aged and elderly males. Cutaneous metastasis of EA is extremely rare. We report the case of a 41-year-old woman presenting with a painful bluish, bulla-like lesion on the distal extent of the left third finger. The patient had recently been diagnosed with mediastinal EA with disseminated metastases. The skin biopsy specimen revealed metastatic EA. This is thought to be the first reported metastasis of EA to the finger. Whenever a patient has metastatic disease, acrometastases should be considered in the differential diagnosis of inflammatory lesions of the digits and a skin biopsy should be performed.

Association between P478S polymorphism of the filaggrin gene and risk of psoriasis in a Chinese population in Taiwan.

Abnormal keratinocyte terminal differentiation is one of the important characteristics of psoriatic lesions. Filaggrin (FLG) is a key protein that facilitates the terminal differentiation of the epidermis. Thus, FLG genetic variants may modify the risk of psoriasis. In total, 314 patients with psoriasis and 611 control subjects were analyzed for the presence of FLG R501X, 2282del4 mutations, and P478S (rs11584340, C/T base change) polymorphism by polymerase chain reaction (PCR). The analysis revealed that both the R501X and 2282del4 mutations were not present in a subset of 200 patients (64%) with psoriasis. In contrast, a marginally significant difference (P = 0.020) was found in the distribution of rs11584340 genotype frequencies between psoriatic patients and controls. The frequency of the TT genotype in psoriasis patients was significantly higher than in controls (37.9% vs. 29.1%, respectively, P = 0.007). The T allele frequency of patients (60.5%) was also significantly higher than that of controls (53.9%) (P = 0.007). After adjusting for age and gender, carriers of the TT genotype were 1.46 (95% CI, 1.08-1.96) times more likely than non-carriers to have psoriasis (P = 0.013). In conclusion, our results suggest that FLG P478S polymorphism may confer susceptibility to the development of psoriasis among Taiwanese Chinese.

Inactivation of the tight junction gene CLDN11 by aberrant hypermethylation modulates tubulins polymerization and promotes cell migration in nasopharyngeal carcinoma.

BACKGROUND: Aberrant hypermethylation of cellular genes is a common phenomenon to inactivate genes and promote tumorigenesis in nasopharyngeal carcinoma (NPC). METHODS: Methyl binding domain (MBD)-ChIP sequencing of NPC cells, microarray data of NPC biopsies and gene ontology analysis were conducted to identify a potential tumor suppressor gene CLDN11 that was both hypermethylated and downregulated in NPC. Bisulfite sequencing, qRT-PCR, immunohistochemistry staining of the NPC clinical samples and addition of methylation inhibitor, 5'azacytidine, in NPC cells were performed to verify the correlation between DNA hypermethylation and expression of CLDN11. Promoter reporter and EMSA assays were used to dissect the DNA region responsible for transcription activator binding and to confirm whether DNA methylation could affect activator's binding, respectively. CLDN11 was transiently overexpressed in NPC cells followed by cell proliferation, migration, invasion assays to characterize its biological roles. Co-immunoprecipitation experiments and proteomic approach were carried out to identify novel interacting protein(s) and the binding domain of CLDN11. Anti-tumor activity of the CLDN11 was elucidated by in vitro functional assay. RESULTS: A tight junction gene, CLDN11, was identified as differentially hypermethylated gene in NPC. High methylation percentage of CLDN11 promoter in paired NPC clinical samples was correlated with low mRNA expression level. Immunohistochemistry staining of NPC paired samples tissue array demonstrated that CLDN11 protein expression was relatively low in NPC tumors. Transcription activator GATA1 bound to CLDN11 promoter region - 62 to - 53 and its DNA binding activity was inhibited by DNA methylation. Re-expression of CLDN11 reduced cell migration and invasion abilities in NPC cells. By co-immunoprecipitation and liquid chromatography-tandem mass spectrometry LC-MS/MS, tubulin alpha-1b (TUBA1B) and beta-3 (TUBB3), were identified as the novel CLDN11-interacting proteins. CLDN11 interacted with these two tubulins through its intracellular loop and C-terminus. Furthermore, these domains were required for CLDN11-mediated cell migration inhibition. Treatment with a tubulin polymerization inhibitor, nocodazole, blocked NPC cell migration. CONCLUSIONS: CLDN11 is a hypermethylated and downregulated gene in NPC. Through interacting with microtubules TUBA1B and TUBB3, CLDN11 blocks the polymerization of tubulins and cell migration activity. Thus, CLDN11 functions as a potential tumor suppressor gene and silencing of CLDN11 by DNA hypermethylation promotes NPC progression.

Malignant cutaneous tumors of the scalp: a study of demographic characteristics and histologic distributions of 398 Taiwanese patients.

BACKGROUND: The scalp is a unique anatomic region, in which pilosebaceous follicles are concentrated. OBJECTIVE: We sought to investigate demographic characteristics and histologic distributions of malignant scalp tumors. METHODS: Primary and metastatic scalp malignancies diagnosed histopathologically between 1983 and 2003 were reviewed. Age at diagnosis, sex, and histologic types were analyzed. RESULTS: A total of 398 Taiwanese patients (200 males, 198 females) were selected. Age at diagnosis ranged from 3 to 103 years. Most malignant scalp tumors (69.8%) occurred in those 50 years or older. Basal (41.2%) and squamous (16.6%) cell carcinomas were the most common histologic types. Surprisingly, metastatic tumors (12.8%) came in third, in which lung cancers were the most frequent primary tumor in both male and female patients. LIMITATIONS: In our series, the case number of metastatic scalp malignancies was underestimated because not all patients with metastatic scalp tumors received a scalp skin biopsy. CONCLUSION: Because a wide spectrum of primary and metastatic malignancies can occur on the scalp, scalp inspection should be included in general screening for either skin or internal cancers.

Simulation of shear bands with Soft PARticle Code (SPARC) and FE.

The aim of this paper is to numerically investigate the development, thickness and orientation of shear bands, in biaxial test with two approaches towards solving problems of continuum mechanics, namely the meshless "Soft PARticle" method and the mesh based Finite Element method. Soft PArticle Code (SPARC) is a straightforward collocation numerical method based on strong formulation, in which a first order polynomial basis is adopted for the evaluation of spatial derivatives in partial differential equations. A novel nonlinear constitutive model- barodesy for clay, is adopted in this study. The biaxial test, which involves homogeneous, and later inhomogeneous localized deformation is simulated using the Soft PArticle Code and the Finite Element method. The inclination and thickness of the shear bands are evaluated and analysed with the earlier experimental, theoretical and numerical investigations. Furthermore, simulation results are compared and presented to demonstrate the advantages and limitations of SPARC in comparison to FE method.

Intrinsically Stretchable Nanostructured Silver Electrodes for Realizing Efficient Strain Sensors and Stretchable Organic Photovoltaics.

In this study, a new hybrid electrode featuring a high gauge factor of >30, decent stretchability (100% of the original conductivity can be retained after 50 cycles of stretching under a 20% strain without prestrain treatment), high transmittance (>70%) across 400-900 nm, and a good sheet resistance (<50 Ω sq-1) was successfully exploited. These superior properties were revealed to originate from the reversible phase separation endowed by the nanogranular-like morphology formed in Ag. Owing to such discrete nanomorphology, the free volume within this Ag electrode is susceptible to the applied tensile strain and the ensuing change in conductivity enables the realization of an efficient strain sensor. Besides, a representative PTB7-th:PC71BM organic photovoltaic (OPV) using this electrode (with the assistance of a wrinkled scaffold to reinforce the stretchability of the active layer) can exhibit a power-conversion efficiency (PCE) of 6% along with high deformability, for which 75% of its original PCE is retained after 50 cycles of stretching under a 20% strain. Meanwhile, a representative all-polymer OPV consisting of a PTB7-th:N2200 blend, in which the N2200 has a better mechanical stretchability than that of PC71BM, can maintain over 96% of its original PCE after 50 cycles of stretching (under a 20% strain) without employing the wrinkled scaffold. Such promising performance in stretchable OPVs is among the state-of-the-art results reported to date.

Growth and characterization of textured well-faceted ZnO on planar Si(100), planar Si(111), and textured Si(100) substrates for solar cell applications.

In this work, textured, well-faceted ZnO materials grown on planar Si(100), planar Si(111), and textured Si(100) substrates by low-pressure chemical vapor deposition (LPCVD) were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), and cathode luminescence (CL) measurements. The results show that ZnO grown on planar Si(100), planar Si(111), and textured Si(100) substrates favor the growth of ZnO(110) ridge-like, ZnO(002) pyramid-like, and ZnO(101) pyramidal-tip structures, respectively. This could be attributed to the constraints of the lattice mismatch between the ZnO and Si unit cells. The average grain size of ZnO on the planar Si(100) substrate is slightly larger than that on the planar Si(111) substrate, while both of them are much larger than that on the textured Si(100) substrate. The average grain sizes (about 10-50 nm) of the ZnO grown on the different silicon substrates decreases with the increase of their strains. These results are shown to strongly correlate with the results from the SEM, AFM, and CL as well. The reflectance spectra of these three samples show that the antireflection function provided by theses samples mostly results from the nanometer-scaled texture of the ZnO films, while the micrometer-scaled texture of the Si substrate has a limited contribution. The results of this work provide important information for optimized growth of textured and well-faceted ZnO grown on wafer-based silicon solar cells and can be utilized for efficiency enhancement and optimization of device materials and structures, such as heterojunction with intrinsic thin layer (HIT) solar cells.

Finite-size domains in membranes with active two-state inclusions.

The distribution of inclusion-rich domains in membranes with active two-state inclusions is studied by simulations. Our study shows that typical size of inclusion-rich domains (L) can be controlled by inclusion activities in several ways. When there is effective attraction between state-1 inclusions, we find: (i) Small domains with only several inclusions are observed for inclusions with time scales (approximately 10(-3)s) and interaction energy [approximately Omicron(kBT)] comparable to motor proteins. (ii) L scales as 13 power of the lifetime of state-1 for a wide range of parameters. (iii) L shows a switch-like dependence on state-2 lifetime k12(-1). That is, L depends weakly on k12 when k12k12*, the crossover k12* occurs when the diffusion length of a typical state-2 inclusion within its lifetime is comparable to L. (iv) Inclusion-curvature coupling provides another length scale that competes with the effects of transition rates.