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Anabolic-androgenic steroid (AAS) use is known to be associated with other psychiatric disorders, such as body image disorders, conduct disorder/sociopathy, and other substance use disorders (SUD) – but the causal pathways among these conditions remain poorly delineated.
We created a directed acyclic graph to diagram hypothesized relationships among AAS use and dependence, body image disorder (BID), conduct disorder/sociopathy, and other SUD. Using proportional hazards models, we then assessed potentially causal relationships among these variables, using a dataset of 233 male weightlifters, of whom 102 had used AAS.
BID and conduct disorder/sociopathy both strongly contributed to the development of AAS use, but did not appear to contribute further to the progression from AAS use to AAS dependence. Other SUD beginning prior to first AAS use – whether broadly defined or restricted only to opioids – failed to show an effect on AAS use or progression to AAS dependence. Conversely, AAS use contributed significantly to the subsequent first-time development of opioid use disorders but did not significantly increase the risk for first-time development of non-opioid SUD, taken as a whole.
Our analysis suggests that AAS use and other SUD are mutually attributable to underlying conduct disorder/sociopathy. SUD do not appear to represent a ‘gateway’ to subsequent AAS use. AAS use may represent a gateway to subsequent opioid use disorder, but probably not to other SUD.
Lactococcus lactis ssp. lactis JCM5805 has been shown to be a rare lactic acid bacterium that can activate plasmacytoid dendritic cells in both murine and human species. In this study, we carried out a randomised placebo-controlled double-blind experiment to evaluate its effect on the pathogenesis of influenza-like illness during the winter season. A total of 213 volunteers were divided into two groups, which received either yogurt made with L. lactis JCM5805 or a placebo beverage daily for 10 weeks. In the JCM5805 group, the cumulative incidence days of ‘cough’ and ‘feverishness’, which are defined as major symptoms of an influenza-like illness, were significantly decreased compared with the placebo group. In addition, peripheral blood mononuclear cells prepared from volunteers were cultured in the presence of inactivated human influenza virus A/H1N1 (A/PR/8/34). IFN-α elicited by A/H1N1 tended to be higher in the JCM5805 group compared with the placebo group, and an IFN-α-inducible antiviral factor, interferon-stimulated gene 15 (ISG15), elicited by A/H1N1 was significantly higher in the JCM5805 group compared with the placebo group after the intake period. These results suggest that intake of JCM5805 is able to prevent the pathogenesis of an influenza-like illness via enhancement of an IFN-α-mediated response to the influenza virus.
In 2013, an unusual increase of paratyphoid fever cases in travellers returning from Cambodia was reported in Japan. From December 2012 to September 2013, 18 cases of Salmonella Paratyphi A infection were identified. Microbiological analyses revealed that most isolates had the same clonal identity, although the epidemiological link between these cases remains unclear. It was inferred that the outbreak was caused by a common and persistent source in Cambodia that was likely to have continued during 2014. The information of surveillance and laboratory data from cases arising in travellers from countries with limited surveillance systems should be timely shared with the country of origin.
Structure-related ionization energy (IE) of vacuum-deposited titanyl-phthalocyanine (OTiPc) thin films was investigated by using in situ ultraviolet photoelectron spectroscopy (UPS) and X-ray diffractometry. Distinct molecular orientations (i.e. lying-flat and standing-up orientation) in different polymorphous (i.e. monoclinic β-phase and triclinic α-phase) were observed on a surface of polycrystalline (poly-) Au and octadecyltrichlorosilane-self assembled monolayer (OTS-SAM). For the two structures IE of the highest occupied molecular orbital (HOMO) of OTiPc thin films altered significantly by 0.55 eV. The different IE was attributed to surface dipole potential and strong intermolecular interaction.
We observed significant reduction of thermal conductivity in semiconducting composite films of Si and molybdenum (Mo)-silicide nanocrystals (NCs). These films were synthesized by phase separation due to annealing at 700 -1000°C from sputtered amorphous Mo–Si alloy. Transmission electron microscope images showed that the NCs were grown to diameters of∼10 nm in the films by annealing at 800°C. Raman scattering spectra showed lower shift of peak positions of Si transverse optical (TO) phonon due to the confinement effect and the tensile stress. The electrical resistivity of the films was 0.17- 9 Ωm at room temperature and showed a semiconducting temperature dependence at 20-400 K. Thermal conductivity of the film was reduced to 4.4 W/mK by enhancement of phonon scattering at NC interfaces, suggesting that the composite film is promising as a high-efficiency Si-based thermoelectric material.
In this paper we propose a few helium ion microscope (HIM)-based methods for sample preparation and modification. In particular we report the use of the HIM to make thin wedge SrTiO3 samples without significant artifacts, the possibility to reshape thin metal lines on an electron transparent membrane and the new method of HIM sample preparation by in situ heating of the samples during He-beam illumination.
This experimental study presents a comparison of differently tensile stressed silicon nitride (SiN) layers and their response to irradiation in a vacuum ultraviolet (VUV) curing system. Therefore, three types of silicon nitride with initial stress levels of 450 MPa, 700 MPa and 980 MPa were deposited by plasma enhanced chemical vapor deposition (PECVD). In contrast to industrial standard VUV curing with broadband lamps ≥ 220 nm radiation wavelengths, we analyzed the effects of curing with single wavelengths at 172 nm and 222 nm. The samples were characterized by Fourier Transform Infrared Spectroscopy, ellipsometry, and wafer bow measurement. It could be shown that high energy photons are able to dehydrogenize SiN films more than lower energetic photons compared with lower Si-N-Si crosslinking effects. Furthermore, we could show that a dual combined 172 nm and 222 nm VUV curing procedure can produce films with very low hydrogen concentration and high percentage of structural units consisting of Si-N-Si bonds. In conclusion of this study, an up to +900 MPa stress increasing process could be established.
We carried out laser ablation of three organic molecules, rubrene (Rb), Oralith Brilliant Pink R (BP) and quinacridonequinone (QQ) in a poor solvent, water. As a result, nanoparticles of BP and QQ were formed, but those of Rb were not formed because of photodissociation. For a rigid molecule, QQ, optical properties of colloidal solutions were investigated in relation to the size of the included nanoparticles. A linear correlation between the blue shift of the absorption peak energy and the decrease in the diameter of the nanoparticles was found, indicating that the nanoparticle diameter can be easily estimated from the absorption spectrum of a colloidal solution. From the solution, a nanoparticle film was fabricated on an electrode by the electrophoretic deposition method.
Embedded Si nano-particles of average size around 5nm were synthesized in an amorphous Si matrix by two stage ion implantation processes. It has been observed that amorphous Si (a-Si) layers were recrystallized using 50 MeV Au ions with enhanced regrowth rate with activation energy in the range of 0.29 eV. During the crystallization process Si nanocrystals were formed in the a-Si layers due to sudden quenching of the molten tracks created by MeV Au ions. The recrystalizations were confirmed by Rutherford backscattering spectrometry-Channeling (RBSC) technique. The structural modification and nanocluster creation that emerged during recrystallization process was observed in high-resolution transmission electron microscopy and photoluminescence (PL) spectroscopy. The PL emission was observed over a broad band of 2.8 – 3.4 eV and centered at 3.25 eV. The Si nano-crystal formation can be explain by a mechanism combining the melting within the ion tracks by thermal spike process and the subsequent recrystallization nucleated from the crystalline sides at the interface.
In this work, the first-principles computational scheme of electron-ion dynamics based on the time-dependent density functional theory is presented as a tool to study dynamical phenomena induced by light. Two applications of computations for photo-induced phenomena are shown. The one is structural change induced by intense and short laser shot with a purpose to simulate experiments using the femtosecond laser. The other is photo-excitation and subsequent carrier splitting into electrons and holes, which is a key process needed in photovoltaic materials.
Ge quantum dots were grown on Si(100)-(2x1) using pulsed laser deposition while the laser is also exciting the substrate during film growth. The growth mode and morphology was probed by scanning tunneling microscopy (STM). Epitaxial growth at a substrate temperature of ∼250 °C was achieved by using laser excitation of the substrate. The morphology of the quantum dots changed with increased laser excitation energy density although the faceting of the individual quantum dots remained the same. A purely electronic mechanism of enhanced surface diffusion of the Ge adatoms is proposed.
Co-implantation, with overlapping implantation projected ranges, of Si and of the doping species (P, As, or B), followed by a single thermal anneal step, is proved to be a viable route to form doped Si-nc’s embedded in SiO2, with diameters of a few nanometers. Extensive results of the evolution of the Si-nc’s related photoluminescence, as a function of the dopant implanted dose, are presented and discussed. Atomic Probe Tomography (APT) is used to image directly the spatial distribution of the various species at the atomic scale. The 3D APT data demonstrate that n-type dopant atoms (P and As) are efficiently introduced in the "bulk" of the Sinanocrystals, whereas B atoms are preferentially located at their periphery, at the Si/SiO2 interface.
We describe a scalable synthesis process for the production and patterning of polymer matrix nanocomposites (PMNCs) using femtosecond laser irradiation to target specific functional behaviors. A modified, in situ chemical vapor deposition (CVD), nanoinfusion process was used to nucleate and grow nanoparticles in the bulk of an optically transparent polytetrafluoroethylene-co-hexafluoropropylene (FEP) polymer matrix. Metallic nanoparticles synthesized with this process can have a strong optical absorption at their surface plasmon resonance (SPR) frequency and we have utilized this property to selectively irradiate and pattern nanocomposites via femtosecond, photothermal heating. If the nanoparticle environment includes species used for chemical vapor deposition, the heat causes a localized decomposition of the precursor species in the immediate vicinity of the nanoparticle leading to a variety of core-shell nanostructures. Using this processing scheme, we have grown shells of tungsten oxide around silver nanoparticles within the polymer matrix resulting in a 40 nm red shift in the SPR of the silver nanoparticles in regions of the material exposed to femtosecond laser pulses. This process has also been adapted to polymers containing tungsten oxide nanoparticles so that the photocatalytic behavior of the particles could be used to the decompose precursor species in the immediate vicinity of the irradiated nanoparticles. These results demonstrate that, by using optical masks and laser processing, it is possible to synthesize nanocomposites with a high degree of control over the location, composition, size, and distribution of nanoparticles within a polymer matrix resulting in patterned materials with tailored electrical, optical, and photocatalytic properties.
We have employed atomic force and Kelvin-Probe force microscopy to study graphene sheets exfoliated on TiO2 under the influence of local heating achieved by laser irradiation. Exfoliation and irradiation took place under ambient conditions, the measurements were performed in ultra high vacuum. We show that after irradiation times of 6 min, an increase of the surface potential is observed which indicates a decrease of p-type carrier concentration. We attribute this effect to the removal of adsorbates like water and oxygen. After irradiation times of 12 min our topography images reveal severe structural modifications of graphene. These resemble the nanocrystallite network which form on graphene/SiO2 but after much longer irradiation times. From our results we propose that short laser heating at moderate powers might offer a way to clean graphene without inducing unwanted structural modifications.
We synthesized amorphous semiconductor films composed of Mo-encapsulating Si clusters (MoSin : n∼10) on solid substrates. The MoSi10 films had Si networks similar to hydrogenated amorphous Si and an optical gap of 1.5 eV. Electron spin resonance signals were not observed in the films indicating that dangling bonds of Si were terminated by Mo atoms. We fabricated thin-film-transistors using the MoSi10 film as a channel material. The electric field effect of the film was clearly observed. This suggests that the density of mid-gap states in the film is low enough for the field effect to occur.
We present a first-principles lattice dynamics for the assembly of the transition-metal (M)-encapsulated Sin clusters in amorphous phase (a-MSin), which has been proposed as a potential candidate for the channel material of the next-generation thin-film transistors (TFTs) [N. Uchida et al., Appl. Phys. Express1, 121502 (2008)]. The shape of calculated vibrational density of states (VDOS) curve of a-MoSi10 is similar to the counterpart of the high pressure phase of a-Si (HPA-Si) although the present systems are obtained as a result of pressure relaxation. Its radial distribution function (RDF) among Si themselves is characterized by the absence of a gap between the first and second shells, which is also the case in . We further present the VDOS of a-WSi10, whose curve shape is again similar to that of HPA-Si. A difference between a-MoSi10 and a-WSi10 is that the W-atom displacement components extracted from the vibration eigenvectors are mainly distributed over a lower frequency range (< ~ 150 cm-1) than the Mo counterpart (~ 150 cm-1 to ~ 300 cm-1). This may be attributed to a larger atomic mass of W than Mo.
We present the ionization of decaborane (B10H14) and formation of hydrogen- and boron-contents-controlled B10-yHx+ through the charge transfer from ambient gas ion to decaborane molecules in an external quadrupole static attraction ion trap. The charge transfer energy is estimated from the experimentally observed products. PBE0/6-311+G(d)//B3LYP/6-31G(d) level of DFT calculations are conducted to investigate the mechanism of charge transfer from ambient gas ion. The calculation of the difference of ionization energies and mismatch of orbital energies between decaborane and ambient gas reveals the mechanism of ionization.
This article proposes clause-level evaluation detection, which is a fine-grained type of opinion mining, and describes an unsupervised lexicon building method for capturing domain-specific knowledge by leveraging the similar polarities of sentiments between adjacent clauses. The lexical entries to be acquired are called polar atoms, the minimum human-understandable syntactic structures that specify the polarity of clauses. As a hint to obtain candidate polar atoms, we use context coherency, the tendency for the same polarity to appear successively in a context. Using the overall density and precision of coherency in the corpus, the statistical estimation picks up appropriate polar atoms from among the candidates, without any manual tuning of the threshold values. The experimental results show that the precision of polarity assignment with the automatically acquired lexicon was 83 per cent on average, and our method is robust for corpora in diverse domains and for the size of the initial lexicon.
A large deformation of bulk wood using slipping between the wood cells has been found just like a plastic deformation generated by slip band in metallic materials. This phenomenon is caused by the hierarchical structure of the wood cell, and the intercellular layer becomes selectively softened in moistened states of wood. In such conditions, bulk wood subject to compression at elevated temperatures can easily be deformed perpendicular to the longitudinal direction of the cells by shear flow stress after being collapsed.