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This study aims at exploring alterations of major metabolites and metabolic pathways in retinopathy of prematurity (ROP) infants and identifying biomarkers that may merit early diagnosis of ROP. METHODS. We analyzed targeted metabolites from 81 premature infants (<34 weeks of gestational age), including 40 ROP cases (15 males and 25 females, birth weight 1.263 ± 0. 345 kg, gestational age 31.20 ± 4.62 weeks) and 41 cases (30 males, 11 females, birth weight 1.220 ± 0.293 kg, gestational age 30.96 ± 4.17 weeks) of well-matched non-ROP controls. Metabolites were measured by ultra-performance liquid chromatographytandem mass spectrometry. Standard multivariate and univariate analysis was performed to interpret metabolomic results. RESULTS. Glycine, glutamate, leucine, serine, piperidine, valine, tryptophan, citrulline, malonyl carnitine (C3DC), and homocysteine were identified as the top discriminant metabolites. In particular, discriminant concentrations of C3DC and glycine were also confirmed by univariate analysis as statistically significant different between ROP and non-ROP infants. CONCLUSIONS. This study gained an insight into the metabolomic aspects of ROP development. We suggest that higher blood levels of C3DC and glycine can be promising biomarkers to predict the occurrence, but not the severity of ROP.

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The last two decades have witnessed the rising prevalence of both co-publishing and retraction.Focusing on research collaboration, this paper utilizes a unique dataset to investigate factors contributing to retraction probability and elapsed time between publication and retraction. Data analysis reveals that the majority of retracted papers are multi-authored and that repeat offenders are collaboration prone. Yet, all things being equal, collaboration, in and of itself, does not increase the likelihood of producing flawed or fraudulent research, at least in the form of retraction. That holds for all retractions and also retractions due to falsification, fabrication, and plagiarism (FFP). The research also finds that publications with authors from elite universities are less likely to be retracted, which is particularly true for retractions due to FFP. China stands out with the fastest retracting speed compared to other countries. Possible explanations, limitations, and policy implications are also discussed.

A Pd-catalyzed decarboxylative approach for the modular synthesis of highly functionalized pyrroles is presented. This protocol utilizes readily available cyclic carbonates and amines as reaction partners and only generates CO2 and H2O as byproducts. This methodology could be operated at room temperature and open to air, thus serving as an ideal means for the derivatization of bioactive compounds. Mechanism investigations suggested that the stereoselective formation of the (Z)-configured γ-amino ketone intermediate is crucial for the success of the reaction.

Semiconductor power modules are core components of power electronics in electrified vehicles. Packaging technology often has a critical impact on module performance and reliability. This paper presents a comprehensive review of the automotive power module packaging technologies. The first part of this paper discusses the driving factors of packaging technology development. In the second section, the design considerations and a primary design process of module packaging are summarized. Besides, major packaging components, such as semiconductor dies, substrates, and die bonding, are introduced based on the conventional packaging structure. Next, technical details and innovative features of state-of-the-art automotive power modules from major suppliers and original equipment manufacturers are reviewed. Most of these modules have been applied in commercial vehicles. In the fourth part, the system integration concept, printed circuit board embedded packaging, three-dimensional packaging, press pack packaging, and advanced materials are categorized as promising trends for automotive applications. The advantages and drawbacks of these trends are discussed, and it is concluded that a preferable overall performance could be achieved by combining multiple technologies. INDEX TERMS Electric vehicles, power electronics, semiconductor device packaging TABLE I PRIMARY DESIGN CONSIDERATIONS OF MODULE PACKAGING Design considerations Details Size Volume, weight, power density, energy density. Electrical performance Current rating, voltage rating, switching frequency range, power loss, electrical insulation, electromagnetic interference (EMI). Thermal management Temperature distribution, thermal resistance (Rth), heat capacity, coefficient of thermal expansion (CTE). Mechanical strength Thermal stress distribution, material properties (Tensile strength, flexural strength, peel strength, etc.), external shock and vibration. Reliability and fatigue Joints failure, crack propagation, delamination, lifetime under temperature and power cycling. Manufacturability and assembly Manufacture procedure, process temperature and pressure, external connections.

Lightweight materials such as porous ceramics have attracted increasing attention for applications in energy conservation, aerospace and automobile industries. However, porous ceramics are usually weak and brittle; in particular, tiny defects could cause catastrophic failure, which affects their reliability and limits the potential use greatly. Here we report a SiC/SiO 2 nanowire network constructed from numerous well-bonded SiC nanowires coated by a biphasic structure consisting of amorphous SiO 2 and nanocrystal SiC. The as-obtained SiC/ SiO 2 nanowire network is lightweight (360 ± 10 mg cm −3 ), mechanically strong (compressive strength of 16 MPa), and damage-tolerant. The high strength of the network is attributed to the biphasic mixed structure of the binding coating which can restrict the deformation of nanowires upon compression. The lightweight and strong SiC/SiO 2 nanowire network shows potential for engineering applications in harsh environments.

A water-mediated catalytic decarboxylation process toward the formation of polysubstituted furans and (E)-allylic alcohols has been reported. This protocol features wide functional group tolerance, easy operation, and only CO 2 -byproduct generation. These reactions can be performed on a large scale open to air under extremely ambient conditions. A range of control experiments revealed the crucial role of the water for the successful conversions as well as the origin of the chemoselectivity and exclusive stereoselectivity.