115 research outputs found

    A Prospective Study of the Incidence of Retinopathy of Prematurity in China: Evaluation of Different Screening Criteria

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    To investigate the incidence of Retinopathy of Prematurity (ROP) in Beijing, North China, and to evaluate the effectiveness of different ROP screening criteria, we conducted a prospective cohort study in a single-neonatal intensive care unit (NICU). A total of 2997 premature infants with birth weight (BW) ≤ 2000 g and/or gestational age (GA) ≤ 34 weeks had completed ROP screening. ROP was diagnosed in 356 (11.9%) infants. The mean GA was 30.46 ± 1.98 weeks and the mean BW was 1477.35 ± 371.29 g. Of the 59 (2.0%) infants receiving treatment, the mean GA was 29.37 ± 2.10 weeks, and the mean BW was 1240.80 ± 330.71 g. The incidence of ROP declined from 14.7% in 2009 and 11.1% in 2010 to 9.5% in 2011. The United Kingdom (UK) criteria could reduce the screening number by 40.8%, and 3 infants with type I ROP needing treatment were missed, but none in 2011. The United States (US) criteria could reduce the screening number by 66.5%, and 10 infants with type I ROP needing treatment were missed, including one in 2011. So the UK criteria may be appropriate for screening of ROP in our NICU in 2011. Future multisite epidemiologic studies are required to establish suitable ROP screening criteria in China

    NUMERICAL SIMULATION OF ICE MILLING LOADS ON PROPELLER BLADE WITH COHESIVE ELEMENT METHOD

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    In ice-infested waters, propellers of a polar ship are likely to be exposed to ice loads in different scenarios. Propeller milling with ice is one of the most dangerous cases for ice-propeller interaction. In this study, we try to simulate dynamic milling process of ice-propeller and reproduce resulting physical phenomena. Cohesive element method is used to model ice in the simulation. To simulate material properties of ice, an elastoplastic softening constitutive law is developed. Both crushing and fracture failures are included in the ice-propeller milling process. The ice loads in 6 Dofs acting on blades of a propeller are calculated in time domain. The average and standard deviations of simulated dominant ice loads are compared with those from model test. A good agreement is achieved. By varying propeller rotation speed, advance velocity and cutting depth on ice block, the sensitivity study has been carried out. The results show that dominant ice loads are affected much by the three parameters. It is shown that decreasing rotation speed, or increasing advance velocity and cutting depth may lead to higher ice loads. Care should be taken to avoid over-loading on propeller when operating in ice for polar ship

    Asiatic Acid Exhibits Anti-inflammatory and Antioxidant Activities against Lipopolysaccharide and d-Galactosamine-Induced Fulminant Hepatic Failure

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    Inflammation and oxidative stress are essential for the pathogenesis of fulminant hepatic failure (FHF). Asiatic acid (AA), which is a pentacyclic triterpene that widely occurs in various vegetables and fruits, has been reported to possess antioxidant and anti-inflammatory properties. In this study, we investigated the protective effects of AA against lipopolysaccharide (LPS) and d-galactosamine (GalN)-induced FHF and the underlying molecular mechanisms. Our findings suggested that AA treatment effectively protected against LPS/d-GalN-induced FHF by lessening the lethality; decreasing the alanine transaminase and aspartate aminotransferase levels, interleukin (IL)-1β, IL-6, and tumor necrosis factor-α production, malondialdehyde formation, myeloperoxidase level and reactive oxygen species generation (i.e., H2O2, NO, and O2−), and increasing the glutathione and superoxide dismutase contents. Moreover, AA treatment significantly inhibited mitogen-activated protein kinase (MAPK) and nuclear factor-kappa B (NF-κB) signaling pathway activation via the partial induction of programmed cell death 4 (PDCD4) protein expressions, which are involved in inflammatory responses. Furthermore, AA treatment dramatically induced the expression of the glutamate-cysteine ligase modifier subunit, the glutamate-cysteine ligase catalytic subunit, heme oxygenase-1, and NAD (P) H: quinoneoxidoreductase 1 (NQO1), which are largely dependent on activation of the nuclear factor-erythroid 2-related factor 2 (Nrf2) through the induction of AMP-activated protein kinase (AMPK) and glycogen synthase kinase-3β (GSK3β) phosphorylation. Accordingly, AA exhibited protective roles against LPS/d-GalN-induced FHF by inhibiting oxidative stress and inflammation. The underlying mechanism may be associated with the inhibition of MAPK and NF-κB activation via the partial induction of PDCD4 and upregulation of Nrf2 in an AMPK/GSK3β pathway activation-dependent manner

    Identity Authentication Security Management in Mobile Payment Systems

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    Mobile payment is a new payment method offering users mobility, reachability, compatibility, and convenience. But mobile payment involves great uncertainty and risk given its electronic and wireless nature. Therefore, biometric authentication has been adopted widely in mobile payment in recent years. However, although technology requirements for secure mobile payment have been met, standards and consistent requirements of user authentication in mobile payment are not available. The flow management of user authentication in mobile payment is still at its early stage. Accordingly, this paper proposes an anonymous authentication and management flow for mobile payment to support secure transaction to prevent the disclosure of users\u27 information and to reduce identity theft. The proposed management flow integrates transaction key generation, encryption and decryption, and matching to process users\u27 personal information and biometric characteristics based on mobile equipment authentication carrier

    Genome-Wide Transcriptional Profiling of the Response of Staphylococcus aureus to Cryptotanshinone

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    Staphylococcus aureus (S. aureus) strains with multiple antibiotic resistances are increasingly widespread, and new agents are required for the treatment of S. aureus. Cryptotanshinone (CT), a major tanshinone of medicinal plant Salvia miltiorrhiza Bunge, demonstrated effective in vitro antibacterial activity against all 21 S. aureus strains tested in this experiment. Affymetrix GeneChips were utilized to determine the global transcriptional response of S. aureus ATCC 25923 to treatment with subinhibitory concentrations of CT. Transcriptome profiling indicated that the antibacterial action of CT may be associated with its action as active oxygen radical generator; S. aureus undergoes an oxygen-limiting state upon exposure to CT

    Analysis on the endogenous mechanism of big data and tower management framework in intelligent manufacturing enterprises

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    This paper makes an in-depth comparative analysis of years of experience in intelligent manufacturing projects and literature research related to Big Data. The 4.0 value chain model and concept are put forward to carry out the logical analysis of the endogenous relationship drive and endogenous management mechanism of intelligent manufacturing. The intelligent manufacturing business management process under the 4.0 value chain is established, and the tower Big Data management framework of intelligent manufacturing enterprises is innovatively proposed. This paper discusses the connotation, elements and drive relationship of enterprise Big Data from three dimensions of business operation, information drive and management policies. The hierarchical structure and related connotation of Big Data are revealed, and the basic characteristics of intelligent manufacturing enterprises Big Data are analyzed. The purpose of this paper is to clarify the difference of the concept between enterprise Big Data and mass data and open the Big Data fundamental research driven by digitization management. It provides basic innovative ideas and scientific research methods for the new generation of digital virtual simulation, digital factory construction and industrial chain management

    Subinhibitory Concentrations of Thymol Reduce Enterotoxins A and B and α-Hemolysin Production in Staphylococcus aureus Isolates

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    BACKGROUND: Targeting bacterial virulence factors is now gaining interest as an alternative strategy to develop new types of anti-infective agents. It has been shown that thymol, when used at low concentrations, can inhibit the TSST-1 secretion in Staphylococcus aureus. However, there are no data on the effect of thymol on the production of other exotoxins (e.g., alpha-hemolysin and enterotoxins) by S. aureus. METHODOLOGY/PRINCIPAL FINDINGS: Secretion of alpha-hemolysin, SEA and SEB in both methicillin-sensitive and methicillin-resistant S. aureus isolates cultured with graded subinhibitory concentrations of thymol was detected by immunoblot analysis. Hemolysin and tumor necrosis factor (TNF) release assays were performed to elucidate the biological relevance of changes in alpha-hemolysin, SEA and SEB secretion induced by thymol. In addition, the influence of thymol on the transcription of hla, sea, and seb (the genes encoding alpha-hemolysin, SEA and SEB, respectively) was analyzed by quantitative RT-PCR. Thymol inhibited transcription of hla, sea and seb in S. aureus, resulting in a reduction of alpha-hemolysin, SEA and SEB secretion and, thus, a reduction in hemolytic and TNF-inducing activities. CONCLUSIONS/SIGNIFICANCE: Subinhibitory concentrations of thymol decreased the production of alpha-hemolysin, SEA and SEB in both MSSA and MRSA in a dose-dependent manner. These data suggest that thymol may be useful for the treatment of S. aureus infections when used in combination with beta-lactams and glycopeptide antibiotics, which induce expression of alpha-hemolysin and enterotoxins at subinhibitory concentrations. Furthermore, the structure of thymol may potentially be used as a basic structure for development of drugs aimed against these bacterial virulence factors

    Systematic review of the perioperative immunotherapy in patients with non-small cell lung cancer: evidence mapping and synthesis

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    ObjectivesThis study aimed to use evidence mapping to provide an overview of immune checkpoint inhibitors (ICIs) as perioperative treatments for non-small cell lung cancer (NSCLC) and to identify areas of this field where future research is most urgently needed.MethodsMultiple databases (PubMed, EMBASE, Cochrane Library, and Web of Science) were searched to identify clinical trials published up to November 2021 that examined the effect of perioperative ICIs for perioperative treatment of NSCLC. Study design, sample size, patient characteristics, therapeutic regimens, clinical stages, short-term and long-term therapeutic outcomes, surgery associated parameters, and therapeutic safety were examined.ResultsWe included 66 trials (3564 patients) and used evidence mapping to characterize the available data. For surgery associated outcomes, sixty-two studies (2480 patients) provided complete information regarding the use of surgery after neoadjuvant immunotherapy and data on R0 resection were available in 42 studies (1680 patients); for short-term clinical outcomes, 57 studies (1842 patients) evaluated pathologic complete response (pCR) after neoadjuvant immunotherapy and most of included studies achieved pCR in the range of 30 to 40%; for long-term clinical outcomes, 15 studies (1932 patients) reported DFS, with a median range of 17.9-53.6 months; and only a few studies reported the safety profiles of perioperative immunotherapies.ConclusionOur evidence mapping systematically summarized the results of all clinical trials and studies that examined ICIs as perioperative treatments for NSCLC. The results indicated more studies that evaluate long-term patient outcomes are needed to provide a stronger foundation for the use of these treatments
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