203 research outputs found

    Synthetic Approach towards P3EHT-b-PSS Conjugated and Ionic Block Copolymer

    Get PDF
    This work is focused on the design, synthesis and characterization of block copolymers (BCPs) containing both conjugated and polyelectrolyte blocks. This type of rod-coil BCP is considered to have microphase separation which is different compared to coil-coil BCPs. The conjugated block used for studies is regioregular poly(3-alkylthiophene) (P3AT), which can be synthesized by Grignard metathesis (GRIM) polymerization. The polyelectrolyte block used is polystyrene sulfonate with well-defined structure, which can be synthesized by atom transfer radical polymerization (ATRP). Chapter II is focused on evaluation of synthetic routes for P3EHT-b-PSS, including using bifunctional initiator to synthesize both blocks, and separately synthesizing end-functionalized polymer blocks for Cu-Catalyzed Azide-Alkyne Cycloaddition (CuAAC). The advantages and disadvantages of these synthetic routes were summarized to find the best to synthesize P3EHT-b-PSS. Chapter III is focus on the detailed synthesis of propynyl-terminated P3EHT and azido-terminated PNSS, which are the two blocks used for CuAAC to synthesize P3EHT-b-PNSS. The optimum conditions for synthesizing both blocks were found. This synthetic route can achieve better MW, PDI and end-group control compared to other reported synthetic attempts for similar end-group functionalities. CuAAC was also tried to synthesize P3EHT-b-PNSS by using previously mentioned polymer blocks

    A Cumulative migration method for computing rigorous transport cross sections and diffusion coefficients for LWR lattices with Monte Carlo

    Get PDF
    A new method for computing homogenized assembly neutron transport cross sections and diffusion coefficients that is both rigorous and computationally efficient is proposed in this paper. In the limit of a homogeneous hydrogen slab, the new method is equivalent to the long-used, and only-recently-published CASMO transport method. The rigorous method is used to demonstrate the sources of inaccuracy in the commonly applied “out-scatter” transport correction. It is also demonstrated that the newly developed method is directly applicable to lattice calculations performed by Monte Carlo and is capable of computing rigorous homogenized transport cross sections for arbitrarily heterogeneous lattices. Comparisons of several common transport cross section approximations are presented for a simple problem of infinite medium hydrogen. The new method has also been applied in computing 2-group diffusion data for an actual PWR lattice from BEAVRS benchmark.Idaho National Laboratory (Contract DE-AC07-05ID14517

    The relationship between depressive mood and non-suicidal self-injury among secondary vocational school students: the moderating role of borderline personality disorder tendencies

    Get PDF
    BackgroundNon-suicidal self-injury (NSSI) has become an important public health issue of global concern, often occurring in adolescents, and depressive mood is closely related to NSSI. In addition, NSSI is considered a symptom of borderline personality disorder. It has been found that adolescents in secondary vocational schools are more vulnerable to behavior and emotional disorders than those in general high schools. This study investigated the risk factors associated with NSSI affecting secondary vocational school students and analyzed the role of borderline personality disorder tendencies in promoting the occurrence of NSSI among students with depressive moods.MethodsA total of 1,848 Chinese secondary vocational students completed a self-report questionnaire. The homemade NSSI behavior questionnaire, Patient Health Questionnaire-9 and Personality Diagnostic Questionnaire-4 were used in this survey. Binary logistic regression and PROCESS software analysis were used to explore the influencing factors associated with NSSI and to test for moderating effects.ResultsFemale (OR = 3.412, 95% CI 2.301–5.060), drinking history (OR = 2.007, 95% CI 1.383–2.911), history of suicidal death exposure (OR = 3.161, 95% CI 1.999–4.999), depressive mood (OR = 2.436, 95% CI 1.668–3.558) and borderline personality disorder tendencies (OR = 2.558, 95% CI = 1.764–3.711) were independent risk factors for NSSI. Borderline personality disorder tendencies (B = 0.047, p = 0.000) moderated the relationship between depressive mood and NSSI. The stronger the borderline personality tendencies, the more NSSI behavior occurred when they were depressive.ConclusionsBorderline personality disorder tendencies in secondary vocational school adolescents significantly enhance the association of depressive mood with NSSI. There is a moderating role for borderline personality disorder tendencies in depressive mood and NSSI

    Three-dimensional Turbulent Reconnection within Solar Flare Current Sheet

    Full text link
    Solar flares can release coronal magnetic energy explosively and may impact the safety of near-earth space environments. Their structures and properties on macroscale have been interpreted successfully by the generally-accepted two-dimension standard model invoking magnetic reconnection theory as the key energy conversion mechanism. Nevertheless, some momentous dynamical features as discovered by recent high-resolution observations remain elusive. Here, we report a self-consistent high-resolution three-dimension magnetohydrodynamical simulation of turbulent magnetic reconnection within a flare current sheet. It is found that fragmented current patches of different scales are spontaneously generated with a well-developed turbulence spectrum at the current sheet, as well as at the flare loop-top region. The close coupling of tearing-mode and Kelvin-Helmholtz instabilities plays a critical role in developing turbulent reconnection and in forming dynamical structures with synthetic observables in good agreement with realistic observations. The sophisticated modeling makes a paradigm shift from the traditional to three-dimension turbulent reconnection model unifying flare dynamical structures of different scales.Comment: 15 pages, 8 figure, accepted for publication in ApJ

    Integrated analysis of transcriptomics and metabolomics of peach under cold stress

    Get PDF
    Low temperature is one of the environmental factors that restrict the growth and geographical distribution of peach (Prunus persica L. Batsch). To explore the molecular mechanisms of peach brunches in response to cold, we analyzed the metabolomics and transcriptomics of ‘Donghe No.1’ (cold-tolerant, CT) and ‘21st Century’ (cold-sensitive, CS) treated by different temperatures (-5 to -30°C) for 12 h. Some cold-responsive metabolites (e.g., saccharides, phenolic acids and flavones) were identified with upregulation only in CT. Further, we identified 1991 cold tolerance associated genes in these samples and they were significantly enriched in the pathways of ‘galactose metabolism’, ‘phenylpropanoid biosynthesis’ and ‘flavonoids biosynthesis’. Weighted gene correlation network analysis showed that soluble sugar, flavone, and lignin biosynthetic associated genes might play a key role in the cold tolerance of peach. In addition, several key genes (e.g., COMT, CCR, CAD, PER and F3’H) were substantially expressed more in CT than CS under cold stress, indicating that they might be major factors during the adaptation of peach to low temperature. This study will not only improve our understanding towards the molecular mechanisms of peach trees under cold stress but also contribute to the screening and breeding program of peach in the future

    Lactation-associated macrophages exist in murine mammary tissue and human milk

    Full text link
    Macrophages are involved in immune defense, organogenesis and tissue homeostasis. Macrophages contribute to the different phases of mammary gland remodeling during development, pregnancy and involution postlactation. Less is known about the dynamics of mammary gland macrophages in the lactation stage. Here, we describe a macrophage population present during lactation in mice. By multiparameter flow cytometry and single-cell RNA sequencing, we identified a lactation-induced CD11c+^{+}CX3CR1+^{+}Dectin-1+^{+} macrophage population (liMac) that was distinct from the two resident F4/80hi^{hi} and F4/80lo^{lo} macrophage subsets present pregestationally. LiMacs were predominantly monocyte-derived and expanded by proliferation in situ concomitant with nursing. LiMacs developed independently of IL-34, but required CSF-1 signaling and were partly microbiota-dependent. Locally, they resided adjacent to the basal cells of the alveoli and extravasated into the milk. We found several macrophage subsets in human milk that resembled liMacs. Collectively, these findings reveal the emergence of unique macrophages in the mammary gland and milk during lactation

    MafB-restricted local monocyte proliferation precedes lung interstitial macrophage differentiation.

    Full text link
    peer reviewedResident tissue macrophages (RTMs) are differentiated immune cells that populate distinct niches and exert important tissue-supportive functions. RTM maintenance is thought to rely either on differentiation from monocytes or on RTM self-renewal. Here, we used a mouse model of inducible lung interstitial macrophage (IM) niche depletion and refilling to investigate the development of IMs in vivo. Using time-course single-cell RNA-sequencing analyses, bone marrow chimeras and gene targeting, we found that engrafted Ly6C+ classical monocytes proliferated locally in a Csf1 receptor-dependent manner before differentiating into IMs. The transition from monocyte proliferation toward IM subset specification was controlled by the transcription factor MafB, while c-Maf specifically regulated the identity of the CD206+ IM subset. Our data provide evidence that, in the mononuclear phagocyte system, the ability to proliferate is not merely restricted to myeloid progenitor cells and mature RTMs but is also a tightly regulated capability of monocytes developing into RTMs in vivo

    Check on the features of potted 20-inch PMTs with 1F3 electronics prototype at Pan-Asia

    Full text link
    The Jiangmen underground neutrino observatory (JUNO) is a neutrino project with a 20-kton liquid scintillator detector located at 700-m underground. The large 20-inch PMTs are one of the crucial components of the JUNO experiment aiming to precision neutrino measurements with better than 3% energy resolution at 1 MeV. The excellent energy resolution and a large fiducial volume provide many exciting opportunities for addressing important topics in neutrino and astro-particle physics. With the container #D at JUNO Pan-Asia PMT testing and potting station, the features of waterproof potted 20-inch PMTs were measured with JUNO 1F3 electronics prototype in waveform and charge, which are valuable for better understanding on the performance of the waterproof potted PMTs and the JUNO 1F3 electronics. In this paper, basic features of JUNO 1F3 electronics prototype run at Pan-Asia will be introduced, followed by an analysis of the waterproof potted 20-inch PMTs and a comparison with the results from commercial electronics used by the container #A and #B
    corecore