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First-principles calculations have been performed to study the structural, energetic, and electronic properties of δ-Re6MO12 (Re = Ho, Gd, Y; M = U, W). The calculated results indicated that the energetic tendencies for the formation of Frenkel-pair defects of δ-Re6MO12 are consistent with the experimental results, and the Frenkel-pair defects have a significant influence on radiation-induced phase transformation. Density of states (DOS) analysis showed hybridizations between W 5d and O 2p states in Y6WO12 and between U 6d and O 2p states in Re6UO12 (Re = Ho, Gd, Y) are observed, but the interaction orbital is much stronger in Re6UO12 (Re = Ho, Gd, Y) than that in Y6WO12. Bader charge analysis revealed that bond in Re6UO12 (Re = Ho, Gd, Y) is more covalent than bond in Y6WO12. It was proposed that bond may play a more significant role in determining their radiation tolerance. [ABSTRACT FROM AUTHOR]

A 21-year-old Chinese woman presented with a 1-year history of recurrent necrotic papulovesicular lesions distributed on her face, chest and extremities. EBER positivity of the atypical lymphocytes can be detected in all three subtypes of HV-LPD with the percentage of positive cells as the diseases progress, which is essential for differentiating HV-LPD from other lymphoproliferative diseases, such as subcutaneous panniculitis-like T-cell lymphoma and primary cutaneous peripheral T-cell lymphoma. Learning points HV-LPD is a progressive EBV-associated lymphoproliferative disease, including the spectrum from classic HV to severe HV and HVLL. [Extracted from the article]

Background: Physical inactivity is a key contributor to the global burden of disease and disproportionately impacts the wellbeing of people experiencing mental illness. Increases in physical activity are associated with improvements in symptoms of mental illness and reduction in cardiometabolic risk. Reliable and valid clinical tools that assess physical activity would improve evaluation of intervention studies that aim to increase physical activity and reduce sedentary behaviour in people living with mental illness. Methods: The five-item Simple Physical Activity Questionnaire (SIMPAQ) was developed by a multidisciplinary, international working group as a clinical tool to assess physical activity and sedentary behaviour in people living with mental illness. Patients with a DSM or ICD mental illness diagnoses were recruited and completed the SIMPAQ on two occasions, one week apart. Participants wore an Actigraph accelerometer and completed brief cognitive and clinical assessments. Results: Evidence of SIMPAQ validity was assessed against accelerometer-derived measures of physical activity. Data were obtained from 1010 participants. The SIMPAQ had good test-retest reliability. Correlations for moderate-vigorous physical activity was comparable to studies conducted in general population samples. Evidence of validity for the sedentary behaviour item was poor. An alternative method to calculate sedentary behaviour had stronger evidence of validity. This alternative method is recommended for use in future studies employing the SIMPAQ. Conclusions: The SIMPAQ is a brief measure of physical activity and sedentary behaviour that can be reliably and validly administered by health professionals. [ABSTRACT FROM AUTHOR]

Onchocerciasis in camels is caused by adult Onchocerca spp. and results in great economic losses to the camel industry. However, only a few studies on Onchocerca have been conducted, especially regarding the intermediate host and vector(s). In the present study, 192 camels were examined from December and January during 2013 and 2016, and the filarial larvae suspected to be Onchocerca spp. were further identified. Furthermore, aquatic dipteran insects in the living environment of camels were collected from May to September between 2013 and 2017 and dissected. Eventually, onchocercal lesions were observed in 95 of 192 (49%) camels and the captured insects were classified into 49 species from 42 genera in 21 families, among which 18 species were newly recorded in Inner Mongolia and 14 were haematophagous species. The filarial larvae were found in Culicoides puncticollis and identified as Onchocerca fasciata, indicating that C. puncticollis is the vector of O. fasciata in Inner Mongolia. These findings provide an estimate of onchocerciasis infection in camels and an alternative method of identifying insects and screening vectors using molecular methods. Important data are also provided for the diagnosis and control of onchocerciasis, thereby further filling the gap in knowledge regarding transmission vectors in China. [ABSTRACT FROM AUTHOR]

OBJECTIVE: This study aimed to investigate the efficacy and molecular mechanisms of ZSP1603 as a novel anti-fibrotic compound. MATERIALS AND METHODS: The unilateral left pulmonary fibrosis model was established in the Sprague Dawley (SD) rats. The bilateral pulmonary fibrosis model was established in the C57BL/6J mice. The therapeutic treatment regimen began after the induction of pulmonary fibrosis. The preventive treatment regimen began on the first day of bleomycin administration. Animals were randomly divided into the sham, model, Nintedanib, and ZSP1603 treatment groups. Haematoxylin and eosin (H&E) and Masson's trichrome staining were performed to evaluate pulmonary injury, inflammation, and fibrosis. Cell Counting Kit-8 (CCK-8) assay and Western blot were used to investigate the effects and mechanisms of ZSP1603 on the proliferation of primary human pulmonary fibroblasts (pHPFs). The messenger ribonucleic acid (mRNA) expression of transforming growth factor (TGF)-ß1, tissue inhibitor of metalloproteinase 1 (TIMP-1), and collagen 1A1 (COL1A1) in pHPFs was detected by quantitative Real Time-Polymerase Chain Reaction (PCR). RESULTS: ZSP1603 inhibited the proliferation of pHPFs in vitro by blocking the platelet-derived growth factor receptor-β (PDGF-Râ) and extracellular signal-regulated kinase (ERK) signalling pathway. ZSP1603 also inhibited the differentiation of pHPFs by reducing the expression of TGF-â1, TIMP-1, and COL1A1. ZSP1603 significantly attenuated pulmonary injury, inflammation, and fibrosis in vivo in four independent animal studies of pulmonary fibrosis. CONCLUSIONS: ZSP1603 is an effective anti-fibrotic compound with clear mechanisms. [ABSTRACT FROM AUTHOR]

A number of nanosize Ti silicides, Ti5Si3,Ti5Si4, and TiSi, were found to form simultaneously in the amorphous intermixing layer of annealed ultrahigh-vacuum-deposited Ti thin films on (001)Si. Autocorrelation function analysis has been applied to the high-resolution transmission electron microscope images to identify the phases formed in the initial stages of reaction. The intermediate silicide phases were detected to form earlier than that of the previous study owing to the superior sensitivity in detecting nanocrystals in an amorphous layer. The phase formation can be explained from the constructed metastable free-energy diagram. [ABSTRACT FROM AUTHOR]

The growth of pinhole-free epitaxial Yb and Er silicide thin films on (111)Si has been achieved by capping appropriate amorphous Si(a-Si) layer at room temperature followed by annealing at 700 °C in an ultrahigh vacuum chamber. The thickness of the a-Si capping layer was selected to be such that the consumption of Si atoms from the substrate is minimized. The design and reimplementation of the scheme involving appropriate thickness of a-Si capping layer was based on an understanding of the formation mechanism of the pinholes with epitaxial rare-earth islands as diffusion barriers for Si diffusion at the silicide/Si interfaces. [ABSTRACT FROM AUTHOR]

For linear systems in the continuum in which the particles interact with nearest-neighbor forces, the pair distribution function at short distances can be expressed exactly in a simple form. Results are given for various hard-core interaction potentials, in which the attractive potential is either constant (square-well potential), linear, or V-shaped. The second form is related to the depletion interaction. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The formation of iron silicides on (111)Si and effects of ion implantation on phase transformation have been investigated by sheet resistance measurements, grazing-incidence x-ray diffractometry, transmission electron microscopy, energy-dispersive x-ray analysis, and secondary ion mass spectroscopy. Ion implantation was found to enhance the growth of light-emitting β-FeSi[sub 2]. Phase transformation from FeSi to β-FeSi[sub 2] begins at 600°C and completes at 700°C. P[sup +] implantation was found to lower the transformation temperature from 700 to 600°C. Wider than 20 nm As-decorated grain boundaries were observed in the As[sup +]-implanted samples annealed at 600700°C. The As-rich grain boundaries disappeared after 800°C annealing, leading to a decrease in resistivity. [ABSTRACT FROM AUTHOR]

The evolution of vacancy ordering structures in epitaxial YbSi[sub 2-x] thin films on both (111) and (001)Si has been studied by transmission electron microscopy (TEM). Epitaxial YbSi[sub 2-x] thin films were grown on Si by either room temperature deposition with subsequent thermal annealing or deposition at elevated temperature. Epitaxial YbSi[sub 2-x] was found to form in samples annealed at 300 °C for 30 min and the appearance of additional diffraction spots is attributed to the formation of an ordered vacancy superstructure in the epitaxial YbSi[sub 2-x] thin films. In other samples, the split or streaking of extra diffraction spots is attributed to the formation of out-of-step structures. The variation of out-of-step structures with the annealing temperature is correlated to a change in vacancy concentration that makes compressive stress in the Si sublattice relax. From studying plan-view and cross-sectional TEM samples in conjunction with simulated diffraction patterns, the three-dimensional structures of vacancy ordering were determined. The vacancy ordering structures are expected to exert a strong influence on the physical properties of epitaxial rare-earth silicide nanowires grown on (001)Si. [ABSTRACT FROM AUTHOR]

The thickness of a low-temperature silicon (LT-Si) buffer layer has been found to affect the growth of a SiGe overlayer significantly. 300-nm-thick Si[sub 0.7]Ge[sub 0.3] films were grown on 50- to 300-nm-thick LT-Si buffer layers at 450 °C by solid-source molecular beam epitaxy. The threading dislocation density was found to decrease with the thickness of the LT-Si buffer in the thickness range of 50-200 nm. The density remains at the same low level when the thickness was increased from 200 to 300 nm. A relatively dense misfit dislocation network was observed to form at the SiGe/Si interface in samples with the LT-Si buffer layer thickness exceeding 200 nm. It is suggested that the presence of more point defects in the thicker LT-Si buffer layer is more effective to block the propagation of threading dislocations. [ABSTRACT FROM AUTHOR]

The dominant diffusing species in the formation of an amorphous interlayer between Yb thin films and crystalline Si substrates have been determined by a Mo cluster marker experiment. Metal thin films with multilayered structures were deposited on both (111) and (001)Si substrates in an ultrahigh vacuum electron beam evaporation system. The positions of the Mo cluster markers relative to the Si substrates, before and after heat treatment, were determined by high-resolution transmission electron microscopy and energy dispersive analysis of x-ray as well as autocorrelation function analysis. The displacement of the Mo cluster markers in the amorphous interlayer during the Yb-Si interdiffusion indicates that Si atoms constitute the dominant diffusing species during the growth of amorphous interlayer. [ABSTRACT FROM AUTHOR]

High-resolution transmission electron microscopy in conjunction with autocorrelation function analysis have been applied to investigate the evolution of structural order in germanium ion-implanted amorphous silicon (a-Si) layers. A high density of Si nanocrystallites as small as 1 nm in size was detected in as-implanted a-Si layers. The density of embedded nanocrystalline Si was found to diminish in a-Si layers with annealing temperature first then increase. The results are discussed in the context of free energy change with annealing temperature. [ABSTRACT FROM AUTHOR]