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Salvia daiguii Y.K.Wei & Y.B.Huang, a new species from China, is described. Salvia daiguii belongs to Salvia subg. Glutinaria (Raf.) G.X.Hu, C.L.Xiang & B.T.Drew, sect. Sobiso (Raf.) G.X.Hu, A.Takano & B.T.Drew, and is distinguished from morphologically similar species by differences in its habit, leaves, inflorescences and flowers. It has a narrow distribution in a karst region of Yongding District, Hunan Province, central China. A key to the Chinese species of section Sobiso is also presented.
Background: Longitudinal data on health-related quality of life (HRQOL) and fatigue in paediatric Duchenne muscular dystrophy (DMD) are limited. Recently, fatigue was reported to be the greatest predictor of poor HRQOL in paediatric DMD. Understanding the trajectory of HRQOL and its relationship with fatigue may facilitate the development of improved therapeutic strategies. Our objective was to describe three-year changes in HRQOL and fatigue in children with DMD. Methods: Patients identified via the Canadian Neuromuscular Disease Registry received mailed questionnaires (2013–2016). HRQOL was assessed using the PedsQLTM GCS and NMM domains, and fatigue was assessed using the MFS domain (patient- and parent-report). Mean three-year change in scores were computed. Pearson correlations were computed between three-year change in HRQOL and fatigue. Results: Mean decline in MFS scores for patient- and parent-reports were 1.03 and 1.19, respectively. Mean decline in GCS scores for patient- and parent-report were 1.75 and 4.13, respectively. Mean change in NMM scores for patient- and parent-report were 0.72 and -8.36, respectively. Change in MFS score was associated with changes in GCS (r=0.72, p<0.001) and NMM scores (r=0.84, p<0.001) by patient-report. Conclusions: Children with DMD experience worse fatigue and HRQOL over time. Parents perceive a greater decline in HRQOL over time compared to patients.
Background: Fatigue is frequent and disabling in adults with neuromuscular disorders, but not well characterized in paediatric neuromuscular disorders. Recently, fatigue was reported to be associated with poor health-related quality of life in children with Duchenne muscular dystrophy (DMD). Determinants of fatigue—a modifiable symptom—have not been studied in DMD. Our objective was to explore risk factors for fatigue in children with DMD. Methods: Patients aged 4–17 years identified via the Canadian Neuromuscular Disease Registry received mailed questionnaires. Fatigue was assessed using the PedsQLTM Multidimensional Fatigue Scale (patient- and parent-report). Standardized measures for depressive symptoms, sleep disturbances, functional ability and physical activity were used. Spearman’s correlations and Wilcoxon rank-sum tests were computed. Results: Of 194 eligible patients, 64 have responded to date. DMD patients reported greater fatigue than healthy controls from published data. Depressive symptoms were associated with greater fatigue, by patient-report (ρ=-0.44, P<0.001) and parent-report (ρ=-0.40, P=0.002). Sleep disturbances were associated with greater fatigue, by patient-report (ρ=-0.41, P=0.007) and parent-report (ρ=-0.51, P<0.001). Greater functional ability was associated with less fatigue, by parent-report (ρ=0.30, P=0.02). Physical activity and ambulatory status were not associated with fatigue. Conclusions: Fatigue is a significant issue in DMD. Depressive symptoms and sleep disturbances are associated with fatigue, warranting attention in therapeutic strategies to reduce fatigue.
A new approach is proposed to analyze Bremsstrahlung X-rays that are emitted from laser-produced plasmas (LPP) and are measured by a stack type spectrometer. This new method is based on a spectral tomographic reconstruction concept with the variational principle for optimization, without referring to the electron energy distribution of a plasma. This approach is applied to the analysis of some experimental data obtained at a few major laser facilities to demonstrate the applicability of the method. Slope temperatures of X-rays from LPP are determined with a two-temperature model, showing different spectral characteristics of X-rays depending on laser properties used in the experiments.
Limitations in sample size, overly inclusive antibiotic classes, lack of adjustment of key risk variables, and inadequate assessment of cases contribute to widely ranging estimates of risk factors for Clostridium difficile infection (CDI).
To incorporate all key CDI risk factors in addition to 27 antibiotic classes into a single comprehensive model.
Retrospective cohort study.
Kaiser Permanente Southern California.
Members of Kaiser Permanente Southern California at least 18 years old admitted to any of its 14 hospitals from January 1, 2011, through December 31, 2012.
Hospital-acquired CDI cases were identified by polymerase chain reaction assay. Exposure to major outpatient antibiotics (10 classes) and those administered during inpatient stays (27 classes) was assessed. Age, sex, self-identified race/ethnicity, Charlson Comorbidity Score, previous hospitalization, transfer from a skilled nursing facility, number of different antibiotic classes, statin use, and proton pump inhibitor use were also assessed. Poisson regression estimated adjusted risk of CDI.
A total of 401,234 patients with 2,638 cases of incident CDI (0.7%) were detected. The final model demonstrated highest CDI risk associated with increasing age, exposure to multiple antibiotic classes, and skilled nursing facility transfer. Factors conferring the most reduced CDI risk were inpatient exposure to tetracyclines and first-generation cephalosporins, and outpatient macrolides.
Although type and aggregate antibiotic exposure are important, the factors that increase the likelihood of environmental spore acquisition should not be underestimated. Operationally, our findings have implications for antibiotic stewardship efforts and can inform empirical and culture-driven treatment approaches.
Infect. Control Hosp. Epidemiol. 2015;36(12):1409–1416
Dysregulation of the striatum and altered corticostriatal connectivity have been associated with psychotic disorders. Social anhedonia has been identified as a predictor for the development of schizophrenia spectrum disorders. The aim of the present study was to examine corticostriatal functional connectivity in individuals with high social anhedonia.
Twenty-one participants with high social anhedonia score and 30 with low social anhedonia score measured by the Chinese version of the Revised Social Anhedonia Scale were recruited from university undergraduates (age 17–21 years) to undergo resting-state functional MRI scans. Six subdivisions of the striatum in each hemisphere were defined as seeds. Voxel-wise functional connectivity analyses were conducted between each seed and the whole brain voxels, followed by repeated-measures ANOVA for the group effect.
Participants with high social anhedonia showed hyper-connectivity between the ventral striatum and the anterior cingulate cortex and the insula, and between the dorsal striatum and the motor cortex. Hypo-connectivity in participants with high social anhedonia was also observed between the ventral striatum and the posterior cingulate cortex. Partial correlation analyses further showed that the functional connectivity between the ventral striatum and the prefrontal cortex was associated with pleasure experience and emotional suppression.
Our findings suggest that altered corticostriatal connectivity can be found in participants with high levels of social anhedonia. Since social anhedonia has been considered a predictor for schizophrenia spectrum disorders, our results may provide novel evidence on the early changes in brain functional connectivity in at-risk individuals.
Two-step growth method of low pressure chemical vapor deposition(LPCVD) process was employed to fabricate the ZnO:B-TCO film; For the first layer, the seed layer with a heavy doping concentration was deposited on the glass substrate, the film having higher deposition rate were then grown on the top of the first layer; It shows that the doping situations of the seed layer play an important role in electrical and optical performance of the whole ZnO:B-TCO layer, and the combination of this two properties is optimal when the doping ratio (B2H6/DEZ) was 0.4;
The unique properties of silicon oxide materials, no matter intrinsic or doped, utilized in thin film solar cells (TFSCs) in the area of photovoltaic (PV) are making TFSCs one of the most attractive photovoltaic technologies for the development of high-performing electricity production units to be integrated in everyday life. In comparison to other silicon materials, the particular diphasic structure of silicon oxide materials, in which hydrogenated microcrystalline silicon (μc-Si:H) crystallites are surrounded by an oxygen-rich hydrogenated amorphous silicon (a-Si:H) phase, causes them present excellent photoelectrical material properties, such as a low-parasitic absorption in the broadband spectral range, independent controllability of longitudinal and lateral conductivity, refractive indices (3.5-2.0), band gap (2.0-2.6 eV) and conductivity tenability (with orders of 1-10-9 S/cm) with oxygen doping, and so on. Various types of silicon oxide materials, including intrinsic, p- or n- type, further applied in TFSCs have also played significant roles in improving the efficiency of various types of single-, dual-, and triple-junction thin-film solar cells from both the optical and electrical points of view. In this paper, we present our latest progress in studying the performance improvement role of intrinsic or doped silicon oxide materials in pin-type a-Si:H, a-SiGe:H, and μc-Si:H single-junction solar cells. By effectively tuning the band gap values of intrinsic a-SiOx:H materials with oxygen doping and adopting the layers with a suitable band gap (1.86 eV) as the P/I buffer layers of a-Si:H solar cells fabricated on metal organic chemical vapor deposition (MOCVD) boron-doped zinc oxide (ZnO:B) substrates, a significant Voc increases up to 909 mV and an excellent external quantum efficiency (EQE) response of 75% at the 400 nm typical wavelength can be achieved by matching the band gap discontinuity between the p-type nc-SiOx:H window and a-Si:H intrinsic layers. The serious leakage current characteristics of pin-type narrow-gap (Eg<1.5 eV) a-SiGe:H single-junction solar cells can also be finely tuned by integrating an n-type μc-SiOx:H layer with a small oxygen content in addition to improving the long-wavelength response, an effective approach gives rise to the highest FF of 70.62% for pin-type a-SiGe:H single-junction solar cells with an average band gap of 1.48 eV. In addition, our studies proved that the application of p-type μc-SiOx:H window layers in μc-Si:H single-junction solar cells can effectively improve the short-wavelength light coupling by suppressing the parasitic absorption and promoting the anti-reflectivity with a graded refractive index profile. On the basis of the optimum single-junction solar cells with omnipotent silicon oxide materials, an initial efficiency of 16.07% has been achieved for pin-type a-Si:H/a-SiGe:H/μc-Si:H triple-junction solar cells with an active area of 0.25 cm2. The omnipotent properties of silicon oxide layers in TFSCs, including effective optical coupling and trapping, suitability in compensating for the band gap discontinuity, the shunt-quenching capacity, and so on, make them likely to be extended to other types of solar cells such as polycrystalline chalcopyrite Cu(In,Ga)Se2 (CIGS) and perovskite-sensitized solar cells, opening up new opportunities for acquiring solar cells with higher performance.
Background: Improvement of health-related quality of life (HRQOL) is a major goal in chronic disease management and HRQOL has become an important outcome in clinical trials. Longitudinal data on HRQOL are needed to elucidate change over time and to assess effectiveness of interventions; such research is lacking in the paediatric Duchenne Muscular Dystrophy (DMD) population. Methods: We followed up participants from our initial HRQOL study in 2013 a year and a half later. Multidimensional generic and disease-specific measures from the Pediatric Quality of Life Inventory were used to assess HRQOL from child and parent perspectives. Mean changes in HRQOL were calculated. Results: Data collection is ongoing and currently, data from 16 families (out of the initial 98) are available. Preliminary results indicated that by both child and parent reports, there were declines in all domains of HRQOL except for social function, in which there was a slight improvement. Mean decline in HRQOL scores ranged from 1.6 to 8.6 for child reports; and 3.3 to 7.7 for parent reports. Conclusion: HRQOL of boys with DMD deteriorates over time. Our results may be helpful in interpreting patient reported outcomes in forthcoming clinical trials and determining minimally clinically important changes in this population.
Thin films of AgSbS2 (150 nm) are prepared (75 min at 40 °C) via chemical deposition using a solution mixture containing SbCl3, Na2S2O3 and AgNO3. As-deposited films are amorphous. When they are heated in nitrogen at 180-320 °C, crystalline cubic-AgSbS2 films are formed. They show an optical band gap 1.89 eV and photoconductivity 1.8x10-5 Ω-1cm-1. Silver antimony sulfide-selenide film, AgSb(SxSe1-x)2, is produced from the initial amorphous film when it is heated in presence of Se-vapor. XRD analysis confirms the formation of solid solution AgSbS1.25Se0.75 or AgSbSe2 depending on the extent of Se-vapor available during heating. SnO2:F/CdS/AgSbS2/C solar cell shows Voc 610 mV, Jsc 0.88 mA/cm2,FF 0.53 and η 0.28%. In SnO2:F/CdS/Sb2S3/AgSb(SxSe1-x)2/C solar cell, Voc is 582 mV, Jsc 0.99 mA/cm2, FF 0.51 and η 0.29%.
We report a stable CdS/Sb2S3/SnSe heterojunction thin film solar cell deposited on SnO2:F (FTO) – coated glass substrates. Thermal evaporation at 10-5 Torr with substrate temperature of 400 °C was used to deposit Sb2S3 and SnSe thin films of 450 nm and 160 nm, respectively. Thin film Sb2S3 has an optical band gap (Eg) of 1.48 eV and photoconductivity (σp) of 4x10-7 Ω-1 cm-1 and thin film SnSe has an Eg of 1.28 eV and σp of 2 Ω-1 cm-1. The chemically deposited CdS thin film heated at 400 °C shows an Eg of 2.34 eV and σp of 0.1 Ω-1 cm-1. Stabilized solar cell structures with these thin films, FTO/CdS/Sb2S3/SnSe/C-Ag, showed open circuit voltage (Voc) of 0.60 V, short circuit current density (Jsc) of 5.51 mA/cm2 and power conversion efficiency (η) of 0.96% with a fill factor FF of 0.29. In the absence of the SnSe layer, Jsc decreases to 4.77 mA/cm2.
Cu2ZnSnS4 (henceforth CZTS) absorber layers are successfully synthesized by a sulfurization technique of physical vapor deposited precursors. In our previous report, we have clarified that the off-stoichiometry composition of Cu-poor and Zn-rich is desirable to achieve high conversion efficiency. By using CZTS compound target that provide such active composition, we could conduct a simple single sputtering method to prepare CZTS absorber. In our laboratory, a two-stage process of precursor preparation followed by sulfurization is a major fabrication method from the start of this study. We think that this method is suitable for a mass production. An optimization of the sulfurization process is a quite important issue because the active composition was already revealed. In this paper, TG/DTA system available in the H2S atmosphere is introduced to optimize the sulfurization condition. As a result, bump-free CZTS films were prepared successfully and the fluctuation of J-V properties in one substrate was drastically suppressed.
Chemically deposited thin film stack of SnSe-ZnSe-Cu2-xSe was heated in nitrogen with Se vapor at 350-400 oC to produce Cu2ZnSnSe4 (CZTSe) thin films. For this, a thin film of SnSe with 180 nm thickness was deposited at 26 °C from a chemical bath containing tin(II) chloride, triethanolamine, sodium hydroxide, sodium selenosulfate, and a small quantity of polyvinylpyrrolidone. Thin films of ZnSe and Cu2-xSe were subsequently deposited on this SnSe film, also from chemical bath. The CZTSe thin film produced this way shows X-ray diffraction pattern matching that of Cu2ZnSnSe4 (kesterite/stannite) and have a Zn-rich composition. The film has an optical band gap of 0.9-1.0 eV and p-type electrical conductivity, 0.2-0.06 Ω-1 cm-1.
We made dynamical black hole mass measurements from nineteen Seyfert 2 galaxies which host sub-parsec H2O maser disks using the H2O megamaser technique. The nearly perfect Keplerian rotation curves in many of these maser systems guarantee the high accuracy and precision of the black hole mass measurements. With the stellar velocity dispersion (σ∗) of the galaxy bulges measured with the Dupont 2.5 m telescope at Las Campanas Observatory in the South and the Apache Point Observatory (APO) 3.5m telescope in the North, we found that H2O maser galaxies, most of which host pseudo bulges rather than classical bulges, do not all follow the MBH–σ∗ relation shown in the literature. This result is well consistent with the latest findings by Kormendy & Ho (2013) that only early type galaxies and galaxies with classical bulges follow a tight MBH–σ∗ relation. Such a tight correlation may not exist in pseudo bulge galaxies.
Triple supermassive black holes (SMBH) can form during the hierarchical mergers of massive galaxies with an existing binary. Perturbations by a third black hole may accelerate the merging process of an inner binary, for example through the Kozai mechanism. We analyze the evolution of simulated hierarchical triple SMBHs in galactic centers, and find resonances in the evolution of the semi-major axis, the eccentricity and the inclination, for both the inner and the outer orbits of the triple system, which are not only Kozai like. Through resonant oscillations, SMBH can trigger a significant increase of the inner SMBH binary eccentricity shortening the merger timescale expected from gravitational wave (GW) emission. As hierarchical triple SMBHs may be frequent in massive galaxies, the influence of orbital resonances is of great importance to our understanding of black hole coalescence and gravitational wave detection. Although Kozai mechanism is believed to play an important role in this process, detailed studies on the pattern of these resonances is necessary.
An excellent candidate for an earth abundant absorber material is WSe2 which can be directly grown as a p-type semiconductor with a band gap near 1.4 eV. In this work we present the structural, optical, and electrical properties of thin film WSe2 grown via the selenization of sputter deposited tungsten films. We will show that highly textured films with an optical band gap in range of 1.4 eV, and absorption coefficients greater than 105/cm across the visible spectrum can be easily achieved. In addition we will present Hall Effect and carrier density measurements as well, where will show densities in the 1017cm-3 range and p-type Hall mobilities greater than 10 cm2/V-s range can be obtained. We employ these results to numerically simulate solar cells based on this material, where we will show efficiencies greater than 20% are possible.
Secondary phases are likely to occur in the Cu2ZnSnS4 (CZTS) films since the CZTS is thermodynamically stable in only a narrow region of the phase diagram. The CZTS solar cell performance can be influenced by the existence and precipitated position of secondary phases. Therefore, locally investigate the distribution of secondary phases is important to further improve CZTS solar cell efficiency. In this study, two different kinds of transmission electron microscopy imaging techniques, bright field scanning TEM image (BF-STEM) and High-angle annular dark-field (HAADF) image, are applied to analyze the distribution of secondary phases. Due to the atomic number differences between CZTS and secondary phases, secondary phases are evident in the HAADF images. Therefore, HAADF image is a more powerful and convenient method to analyze the secondary phases than the BF-STEM image.
III-V compound multi-junction solar cells have high efficiency potential of more than 50% due to wide photo response, while limiting efficiencies of single-junction solar cells are 31-32%. In order to realize high efficiency III-V compound multi-junction solar cells, understanding and controlling imperfections (defects) are very important. This paper reviews fundamentals of defects and defect management for III-V compound materials, single-junction, multi-junction, space and concentrator solar cells.