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Software is widely used in many application domains. The most popular software are used by millions every day. How to accurately predict and assess the reliability of developed software is becoming increasingly important for project managers and developers. Previous studies have primarily used the software reliability growth model (SRGM) to evaluate and predict software reliability, but prediction results cannot be accurate at particular times or in particular situations. One of the main reasons is that simplified assumptions and abstractions are usually made to simplify the problem when developing SRGMs. Selecting an appropriate SRGM should depend on the key characteristics of the software project. In this article, we propose a deep learning-based approach for software reliability prediction and assessment. Specifically, we clearly demonstrate how to derive mathematical expressions from the computational methods of deep learning models and how to determine the correlation between them and the mathematical formula of SRGMs, and then, we use the back-propagation algorithm to obtain the SRGM parameters. Furthermore, we further integrate some deep learning-based SRGMs and also propose a method for the weighted assignment of combinations. Three real open source software failure datasets are used to evaluate the performance of the proposed models compared to selected SRGMs. The experimental results reveal that our proposed deep learning-based models and their combinations perform better than several classical SRGMs. [ABSTRACT FROM AUTHOR]

Co-doped ZnO thin films have attracted much attention in the field of transparent conductive oxides (TCOs) in solar cells, displays, and other transparent electronics. Unlike conventional single-doped ZnO, co-doped ZnO utilizes two different dopant elements, offering enhanced electrical properties and more controllable optical properties, including transmittance and haze; however, most previous studies focused on the electrical properties, with less attention paid to obtaining high haze using co-doping. Here, we prepare high-haze Ga- and Zr-co-doped ZnO (GZO:Zr or ZGZO) using atmospheric pressure plasma jet (APPJ) systems. We conduct a detailed analysis to examine the interplay between Zr concentrations and film properties. UV-Vis spectroscopy shows a remarkable haze factor increase of 7.19% to 34.8% (+384%) for the films prepared with 2 at% Zr and 8 at% Ga precursor concentrations. EDS analysis reveals Zr accumulation on larger and smaller particles, while SIMS links particle abundance to impurity uptake and altered electrical properties. XPS identifies Zr mainly as ZrO2 because of lattice stress from Zr doping, forming clusters at lattice boundaries and corroborating the SEM findings. Our work presents a new way to fabricate Ga- and Zr-co-doped ZnO for applications that require low electrical resistivity, high visible transparency, and high haze. [ABSTRACT FROM AUTHOR]

• Ga and Zr co-doped ZnO with high haze, high transmittance, and high conductivity. • GZO:Zr deposited by APPJ in one step without changing processing parameters. • High haze (~35%) is achieved by the rougher surface of the as-deposited films. • A facile and cost-effective method suitable for commercial mass production. [Display omitted] Creating textured front electrodes to improve optical path length is promising to enhance the power conversion efficiency of solar cells. Deposition of transparent conductive oxides with textured surfaces usually requires additional processing steps, such as etching and coating nanoparticles. However, this makes the process complicated and inefficient. We demonstrate a one-step fabrication process to deposit high haze gallium and zirconium co-doped zinc oxides (GZO:Zr) prepared by atmospheric pressure plasma jets. GZO:Zr (2 at%) films achieve a low resistivity (7.88 × 10–4 Ω cm), a high haze (34.8%), and a great FoM (8.22 × 10−3 Ω−1). The haze factor increases from 7.19% to 34.8% (+384%) when 2% Zr is doped into GZO films. Such an enhancement of haze is attributed to the increased surface roughness and deterioration of crystallinity. AFM results show that roughness increases from 18.4 to 122 nm after 2% Zr is doped. SEM images show that spherical particles appeared on the film surface when Zr was doped into GZO films. Unlike conventional methods, our method produces hazy transparent electrodes in one step without changing any operational parameters and is suitable for industrial-scale mass production. Our findings pave the way for new applications of co-doping in transparent conductive oxides. [ABSTRACT FROM AUTHOR]

Abstract: An organosilicon/silicon oxide (SiOx) multilayered barrier structure was consecutively deposited onto the polyethylene terephthalate (PET) substrate by plasma-enhanced chemical vapor deposition (PECVD) using tetramethylsilane (TMS) monomer and TMS–oxygen gas mixture, respectively. The thickness of the SiOx film directly deposited onto the PET substrate was firstly designed to perform the best barrier property to water vapor permeation, which also possessed the optimal surface uniformity and Sih name="sbnd" />Si structural order. By insetting an adequate thickness of the organosilicon layer plasma-polymerized from TMS monomer between the SiOx film and PET substrate, the water vapor transmission rate (WVTR) was further improved. The residual internal stress of such organosilicon/SiOx barrier structure was significantly lower than that of a single SiOx film deposited directly on the substrate. The improvement on the structural quality and surface densification of the organosilicon/SiOx barrier structures was discussed and observed from their chemical bond configurations and surface morphologies. Accordingly, low water vapor permeation below the MOCON detection limit (<1×10−2 g/m2/day) was achievable from the PET substrate coated with the 6-pairs of the organosilicon/SiOx multilayered barrier structure by PECVD using the same monomer precursor. [Copyright &y& Elsevier]

Abstract: The effect of a nickel oxide (NiOx) seed layer on the crystallization and photocatalytic activity of the sequentially plasma-enhanced chemical vapor deposited amorphous titanium oxide (TiOx) thin film processed by a post-annealing process was investigated. The evolution of the crystalline structures, chemical bond configurations, and surface/cross-sectional morphologies of the annealed TiOx films, with and without a NiOx seed layer, was examined using X-ray diffractometer, Fourier transform infrared spectrometry, X-ray photoelectron spectroscopy, atomic force microscopy, and field emission scanning electron microscope measurements. Thermo- and photo-induced hydrophilicity was determined by measuring the contact angle of water droplet. Photocatalytic activity after UV light irradiation was evaluated from the decolorization of a methylene blue solution. The crystallization temperature of the TiOx film, deposited on a NiOx seed layer, was found to be lower than that of a pure TiOx film, further improving the thermo- and photo-induced surface super-hydrophilicity. The TiOx film deposited onto the NiOx seed layer, resulting in significant cluster boundaries, showed a rough surface morphology and proved to alleviate the anatase crystal growth by increasing the post-annealing temperature, which yielded a more active surface area and prohibited the recombination of photogenerated electrons and holes. The photocatalytic activity of the NiOx/TiOx system with such a textured surface therefore was enhanced and optimized through an adequate post-annealing process. [Copyright &y& Elsevier]

Abstract: Hydro-oxygenated amorphous titanium oxide (a-TiO x :OH) films were prepared by plasma-enhanced chemical vapor deposition (PECVD) using precursors of titanium tetraisopropoxide (TTIP) and oxygen. The influences of chemical states and crystal quality on the photocatalytic activity were systematically investigated in the as-deposited and post-annealed films. The degree of the photocatalytic activity was deeply correlated with the porosity related to the hydroxyl (OH) groups in the as-deposited amorphous film. The crystallized anatase structures was observed from the 200°C-deposited a-TiO x :OH film after a post-annealing treatment at 400°C. The photocatalytic activity related to the film with anatase structure was markedly superior to that of an amorphous film with porous structures. The larger the crystal size of the anatase structure, the higher the photocatalytic activity obtained. At elevated annealed temperatures, the inferior anatase structure due to the crystalline transformation led to a low photocatalytic activity. It was concluded that the photocatalytic activity of an amorphous TiO x film prepared using PECVD was determined by the porosity originating from the functional OH groups in the film, whereas the crystalline quality of anatase phase in the annealed poly-TiO x film was crucial to the photocatalytic activity. [Copyright &y& Elsevier]

Ovarian teratomas are by far the most common ovarian germ cell tumor. Most teratomas are benign unless a somatic transformation occurs. The designation of teratoma refers to a neoplasm that differentiates toward somatic-type cell populations. Recent research shows a striking association between ovarian teratomas and anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis, a rare and understudied paraneoplastic neurological syndrome (PNS). Among teratomas, mature teratomas are thought to have a greater relevance with those neurological impairments. PNS is described as a neurologic deficit triggered by an underlying remote tumor, whereas anti-NMDAR encephalitis is characterized by a complex neuropsychiatric syndrome and the presence of autoantibodies in cerebral spinal fluid against the GluN1 subunit of the NMDAR. This review aims to summarize recent reports on the association between anti-NMDAR encephalitis and ovarian teratoma. In particular, the molecular pathway of pathogenesis and the updated mechanism and disease models would be discussed. We hope to provide an in-depth review of this issue and, therefore, to better understand its epidemiology, diagnostic approach, and treatment strategies. [ABSTRACT FROM AUTHOR]

Abstract: In this study, the biodegradable poly(lactic acid) (PLA)/montmorillonite (MMT) nanocomposites were successfully prepared by the solution mixing process of PLA polymer with organically-modified montmorillonite (m-MMT), which was first treated by n-hexadecyl trimethyl-ammonium bromide (CTAB) cations and then modified by biocompatible/biodegradable chitosan to improve the chemical similarity between the PLA and m-MMT. Both X-ray diffraction data and transmission electron microscopy images of PLA/m-MMT nanocomposites indicate that most of the swellable silicate layers were disorderedly intercalated into the PLA matrix. Mechanical properties and thermal stability of the PLA/m-MMT nanocomposites performed by dynamic mechanical analysis and thermogravimetric analysis have significant improvements in the storage modulus and 50% loss in temperature when compared to that of neat PLA matrix. The degradation rates of PLA/m-MMT nanocomposites are also discussed in this study. [Copyright &y& Elsevier]

The pyruvate dehydrogenase complex (PDH) critically regulates carbohydrate metabolism. Phosphorylation of PDH by one of the pyruvate dehydrogenase kinases 1–4 (PDK1–4) decreases the flux of carbohydrates into the TCA cycle. Inhibition of PDKs increases oxidative metabolism of carbohydrates, so targeting PDKs has emerged as an important therapeutic approach to manage various metabolic diseases. Therefore, it is highly desirable to begin to establish imaging tools for noninvasive measurements of PDH flux in rodent models. In this study, we used hyperpolarized (HP) 13C-magnetic resonance spectroscopy to study the impact of a PDK2/PDK4 double knockout (DKO) on pyruvate metabolism in perfused livers from lean and diet-induced obese (DIO) mice and validated the HP observations with high-resolution 13C-nuclear magnetic resonance (NMR) spectroscopy of tissue extracts and steady-state isotopomer analyses. We observed that PDK-deficient livers produce more HP-bicarbonate from HP-[1-13C]pyruvate than age-matched control livers. A steady-state 13C-NMR isotopomer analysis of tissue extracts confirmed that flux rates through PDH, as well as pyruvate carboxylase and pyruvate cycling activities, are significantly higher in PDK-deficient livers. Immunoblotting experiments confirmed that HP-bicarbonate production from HP-[1-13C]pyruvate parallels decreased phosphorylation of the PDH E1α subunit (pE1α) in liver tissue. Our findings indicate that combining real-time hyperpolarized 13C NMR spectroscopy and 13C isotopomer analysis provides quantitative insights into intermediary metabolism in PDK-knockout mice. We propose that this method will be useful in assessing metabolic disease states and developing therapies to improve PDH flux. [ABSTRACT FROM AUTHOR]

Service-oriented architecture (SOA) has become an increasingly popular choice for building software application in the last years. An SOA system is an elastic structure that utilizes services discovery and integrates these services to perform specified functions. In general, reliability is a critical system attribute when evaluating the quality of a well-built software applications. But it has to be noted that the phenomenon of error propagation could have significant impacts on system reliability. Propagated errors may be masked or propagated to the system interface, which can thereby lead to a system failure. Much research on reliability evaluation for SOA systems have been proposed in the past. However, most of these studies have neglected the phenomenon of error propagation and the issue of link failure. In this article, we take a different view of error propagation, fault tolerance, and the failure behavior of links between services and try to develop an enhanced SOA reliability prediction model incorporating error propagation and fault tolerance (EP–FT). Different fault tolerance techniques will be selected and integrated into the SOA systems. Additionally, sensitivity analysis is also presented and discussed to determine the critical services in the system. Experiments are performed based on four real-world case studies. We will show and discuss the experimental results of the proposed EP–FT reliability model and simulation-based approach in detail. Our experimental results show that the impact of error propagation on system reliability is not negligible, and the SOA systems with fault tolerance demonstrate higher reliability than those that do not. [ABSTRACT FROM AUTHOR]

Neuroendocrine prostate cancer (NEPC) is an aggressive and lethal variant of prostate cancer (PCa), and it remains a diagnostic challenge. Herein we report our findings of using synaptic vesicle glycoprotein 2 isoform A (SV2A) as a promising marker for positron emission tomography (PET) imaging of neuroendocrine differentiation (NED). The bioinformatic analyses revealed an amplified SV2A gene expression in clinical samples of NEPC versus castration-resistant PCa with adenocarcinoma characteristics (CRPC-Adeno). Importantly, significantly upregulated SV2A protein levels were found in both NEPC cell lines and tumor tissues. PET imaging studies were carried out in NEPC xenograft models with 18F-SynVesT-1. Although 18F-SynVesT-1 is not a cancer imaging agent, it showed a significant uptake level in the SV2A+ tumor (NCI-H660: 0.70 ± 0.14 %ID/g at 50–60 min p.i.). The SV2A blockade resulted in a significant reduction of tumor uptake (0.25 ± 0.03 %ID/g, p = 0.025), indicating the desired SV2A imaging specificity. Moreover, the comparative PET imaging study showed that the DU145 tumors could be clearly visualized by 18F-SynVesT-1 but not 68Ga-PSMA-11 nor 68Ga-DOTATATE, further validating the role of SV2A-targeted imaging for noninvasive assessment of NED in PCa. In conclusion, we demonstrated that SV2A, highly expressed in NEPC, can serve as a promising target for noninvasive imaging evaluation of NED. [ABSTRACT FROM AUTHOR]