Experimental and numerical studies have been performed on the thermal and chemical effects of buffer gas composition on low temperature ignition of iso-octane and n-heptane. Experiments were ...conducted using a recently developed rapid compression machine in the temperature range of 600–850K. Three buffer gases were studied including nitrogen (N2), argon (Ar), and a mixture of Ar and carbon dioxide (CO2) at a mole ratio of 65.1%/34.9%. Iso-octane was studied at 20bar, ϕ=1, and a dilution level of buffer gas to O2 of 3.76:1 (mole ratio). n-Heptane was studied at 9bar, ϕ=1, and a dilution level of buffer gas to O2 of 5.63:1 (mole ratio). For experiments where two-stage ignition was observed, the buffer gas composition had no impact on the first-stage ignition time but, as expected, it caused differences in the total heat release, pressure and temperature rise after the first-stage ignition. As a consequence, significant differences were observed for the total ignition delay time as a function of the buffer gas composition, with up to 40% and 42.5% faster total ignition time for iso-octane and n-heptane, respectively, by using Ar instead of N2. The chemical effects of the buffer gas composition were studied experimentally by comparing the results of the N2 and Ar/CO2 (65.1%/34.9%) mixtures, recognizing that while the Ar/CO2 mixture has the same heat capacity as N2, its predicted combined third-body collision efficiency is about 76% higher than N2. The experimental results showed negligible chemical effects on the first-stage and total ignition delay times. Numerical simulations were carried out over a wider range of temperatures for pure N2, Ar, and CO2 as buffer gases. Results showed that thermal effects are very pronounced and dominated at the negative temperature coefficient and two-stage ignition conditions, which is consistent with the experimental results and previous studies in the literature. However, the simulation results also showed at temperatures higher than 850K, the chemical effects of CO2 became more important than the thermal effects.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Prostate cancer is one of the most common cancers in the world. The results of treatment after hypofractionated radiotherapy only have been reported from several small randomized clinical trials. ...Therefore, we conducted a meta-analysis to compare clinical outcomes of hypofractionated radiotherapy versus conventional radiotherapy in the treatment of intermediate- to high-risk localized prostate cancer.
Relevant studies were identified through searching related databases till August 2018. Hazard ratio (HR) or risk ratio (RR) with its corresponding 95% confidence interval (CI) was used as pooled statistics for all analyses.
The meta-analysis results showed that overall survival (HR = 1.12, 95% CI: 0.93-1.35, p = 0.219) and prostate cancer-specific survival (HR = 1.29, 95% CI: 0.42-3.95, p = 0.661) were similar in two groups. The pooled data showed that biochemical failure was RR = 0.90, 95% CI: 0.76-1.07, p = 0.248. The incidence of acute adverse gastrointestinal events (grade ≥ 2) was higher in the hypofractionated radiotherapy (RR = 1.70, 95% CI: 1.12-2.56, p = 0.012); conversely, for late grade ≥ 2 gastrointestinal adverse events, a significant increase in the conventional radiotherapy was found (RR = 0.75, 95% CI: 0.61-0.91, p = 0.003). Acute (RR = 1.01, 95% CI: 0.89-1.15, p = 0.894) and late (RR = 0.98, 95% CI: 0.86-1.10, p = 0.692) genitourinary adverse events (grade ≥ 2) were similar for both treatment groups.
Results suggest that the efficacy and risk for adverse events are comparable for hypofractionated radiotherapy and conventional radiotherapy in the treatment of intermediate- to high-risk localized prostate cancer.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
To evaluate the effectiveness of repetitive thoracic paravertebral block (TPVB) under ultrasound (US) guidance for acute pain associated to herpes zoster (HZ) and its prophylactic effects on ...post-herpetic neuralgia (PHN).
Patients who suffered from acute pain associated to HZ within 1 week of rash onset were randomized in a ratio of 1:1 to receive a seven-day course antiviral therapy, antiviral therapy with additional US-guided repetitive TPVB using transverse short axial (TSA) approach every 48 h for a week after antiviral therapy. All patients were allowed to receive rescue analgesics. The primary endpoint was HZ burden of illness (HZ-BOI) measured by a severity-by-duration composite pain assessment conducted 1-month post inclusion. Adverse events were also recorded.
A total of 96 patients completed the entire 6-month follow-up. The BOI-30
AUC
was 112.5 (95%CI: 105.2, 119.9) in control group, and 82.7 (95%CI: 75.4, 90.1) in TPVB group (F = 32.252, p<.001) at D30 after inclusion. Compared with control group, significant reductions of BOI-30-90
AUC
, and BOI-90-180
AUC
were observed in TPVB group (F = 11.392, p=.001 at D90; F = 7.467, p=.007 at D180, respectively). At 3 and 6 months after inclusion, the incidence of PHN in TPVB group was significantly lower than control group. Quality of life (QoL) in TPVB group also showed greater improvements at all the time points in all domains of EQ-5D-3L (p<.05). No serious adverse events were observed.
US-guided repetitive TPVB significantly reduced the HZ-BOI and the PHN incidence compared to antiviral therapy alone. It might be considered as an early intervention and preventive strategy to the development of PHN after acute HZ.
KEY MESSAGE
This is a prospective randomized comparative study. We made a hypothesis that US-guided repetitive thoracic paravertebral block (TPVB) using a transverse short axial (TSA) approach to treat thoracic herpes zoster (HZ) in acute phase could reduce the burden of illness associated to acute pain. Moreover, this therapy might be a feasible preventive strategy to reduce the incidence of post-herpetic neuralgia.
To investigate a novel strategy in constructing tissue-engineered corneal stromal equivalent based on amniotic membrane and keratocytes.
The ultrathin amniotic membrane (UAM) was laminated, with ...corneal stromal cells (CSCs) distributed between the space of the layered UAMs. Calcein AM staining was used to evaluate cellular viability, morphology, and arrangement. Immunostaining, qRT-PCR, and Western blot were performed to detect gene and protein expression in keratocytes. Optical coherence tomography visualized the cross sections and thickness of the UAM construction. The microstructure of the CSC-secreted extracellular matrix (ECM) was investigated by scanning electron microscopy and transmission electron microscopy (TEM). To evaluate the feasibility of the multilayer UAM-CSC lamination for surgery, the corneal substitute was used to perform lamellar keratoplasty. Slit lamp microscopy and corneal fluorescein staining were performed in postsurgery observation.
The CSCs maintained their keratocyte phenotype and secreted well-organized ECM on the aligned UAM surface. The four-layer UAM-CSC lamination attained half thickness of the human cornea (250 ± 18 μm) after 8 weeks' culture, which also showed promising optimal transparency. In TEM images, the CSC-generated ECM displayed stratified, multilayered lamellae with orthogonal fibril arrangement, which was similar to the human cornea microstructure. Furthermore, the stromal equivalent was successfully preformed in lamellar keratoplasty. Four weeks post surgery, the substitute was well integrated into the recipient cornea and completely epithelialized without myofibroblast differentiation.
Our study established a novel 3D biomimetic corneal model to replicate the corneal stromal organization with multilayer UAM, which was capable of promoting the development of corneal stroma-like tissues in vitro, establishing a new avenue for basic research and therapeutic potential.
A semi-analytical method is proposed to investigate the dynamic response of a non-circular tunnel with visco-elastic imperfect interface in poroelastic medium. Biot’s dynamic theory is used to ...simulate the saturated poroelastic medium, and the governing equations are solved by reducing them into three Helmholtz equations that the potential functions satisfy. The visco-elastic interface model with elastic and viscosity coefficients is adopted to analyze the interface effect around the non-circular lined tunnel. The analytic solutions of displacements and stresses are expanded in terms of wave functions. Some numerical examples are provided to analyze the effect of visco-elastic interface on the dynamic stress around the tunnel.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Foodborne illnesses caused by bacterial microorganisms are common worldwide and constitute a serious public health concern. In particular, microorganisms belonging to the Enterobacteriaceae and ...Vibrionaceae families of Gram-negative bacteria, and to the Staphylococcus genus of Gram-positive bacteria are important causative agents of food poisoning and infection in the gastrointestinal tract of humans. Recently, variants of these bacteria have developed resistance to medically important chemotherapeutic agents. Multidrug resistant Escherichia coli, Salmonella enterica, Vibrio cholerae, Enterobacter spp., and Staphylococcus aureus are becoming increasingly recalcitrant to clinical treatment in human patients. Of the various bacterial resistance mechanisms against antimicrobial agents, multidrug efflux pumps comprise a major cause of multiple drug resistance. These multidrug efflux pump systems reside in the biological membrane of the bacteria and actively extrude antimicrobial agents from bacterial cells. This review article summarizes the evolution of these bacterial drug efflux pump systems from a molecular biological standpoint and provides a framework for future work aimed at reducing the conditions that foster dissemination of these multidrug resistant causative agents through human populations.
In this paper, a novel image encryption algorithm based on the Once Forward Long Short Term Memory Structure (OF-LSTMS) and the Two-Dimensional Coupled Map Lattice (2DCML) fractional-order chaotic ...system is proposed. The original image is divided into several image blocks, each of which is input into the OF-LSTMS as a pixel sub-sequence. According to the chaotic sequences generated by the 2DCML fractional-order chaotic system, the parameters of the input gate, output gate and memory unit of the OF-LSTMS are initialized, and the pixel positions are changed at the same time of changing the pixel values, achieving the synchronization of permutation and diffusion operations, which greatly improves the efficiency of image encryption and reduces the time consumption. In addition the 2DCML fractional-order chaotic system has better chaotic ergodicity and the values of chaotic sequences are larger than the traditional chaotic system. Therefore, it is very suitable to image encryption. Many simulation results show that the proposed scheme has higher security and efficiency comparing with previous schemes.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The gut microbiota is an important influencing factor of metabolic health. Although dietary interventions with probiotics, prebiotics, and synbiotics can be effective means to regulate obesity and ...associated comorbidities, the underlying shifts in gut microbial communities, especially at the functional level, have not been characterized in great details. In this study, we sought to investigate the effects of synbiotics on the regulation of gut microbiota and the alleviation of high-fat diet (HFD)-induced metabolic disorders in mice.
Specific pathogen-free (SPF) male C57BL/6J mice were fed diets with either 10% (normal diet, ND) or 60% (high-fat diet, HFD) of total calories from fat (lard). Dietary interventions in the HFD-fed mice included (i) probiotic (Bifidobacterium animalis subsp. lactis and Lactobacillus paracasei subsp. paracasei DSM 46331), (ii) prebiotic (oat β-glucan), and (iii) synbiotic (a mixture of i and ii) treatments for 12 weeks. Besides detailed characterization of host metabolic parameters, a multi-omics approach was used to systematically profile the microbial signatures at both the phylogenetic and functional levels using 16S rRNA gene sequencing, metaproteomics and targeted metabolomics analysis.
The synbiotic intervention significantly reduced body weight gain and alleviated features of metabolic complications. At the phylogenetic level, the synbiotic treatment significantly reversed HFD-induced changes in microbial populations, both in terms of richness and the relative abundance of specific taxa. Potentially important species such as Faecalibaculum rodentium and Alistipes putredinis that might mediate the beneficial effects of the synbiotic were identified. At the functional level, short-chain fatty acid and bile acid profiles revealed that all dietary interventions significantly restored cecal levels of acetate, propionate, and butyrate, while the synbiotic treatment reduced the bile acid pools most efficiently. Metaproteomics revealed that the effects of the synbiotic intervention might be mediated through metabolic pathways involved in carbohydrate, amino acid, and energy metabolisms.
Our results suggested that dietary intervention using the novel synbiotic can alleviate HFD-induced weight gain and restore gut microbial ecosystem homeostasis phylogenetically and functionally.
•Synbiotic (SYN) intervention alleviated HFD-induced metabolic disorders.•SYN regulated the microbial population at the diversity and taxonomic levels.•HFD reduces SCFAs production which is restored by dietary interventions.•HFD promotes bile acids formation which is ameliorated by SYN.•SYN regulated microbial functional activities and metabolic pathways.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Four mesophilic actinobacteria (HY002
T
, HY442, HY366
T
and HY285) isolated from the faeces of bats collected in southern China were found to be strictly aerobic, non-motile, rod-shaped, ...oxidase-negative, Gram-stain-positive and catalase-positive. Strains HY002
T
and HY366
T
contained
meso
-diaminopimelic acid as the diagnostic diamino acid and MK-9(H
2
) the sole respiratory quinone. Arabinose, galactose and ribose were detected in the whole-cell hydrolysates of both type strains. The main cellular fatty acids (> 10.0%) of all strains were C
16 : 0
, C
18 : 1
ω
9
c
, 10-methyl-C
18 : 0
and summed feature 3. Strains HY002
T
and HY366
T
contained diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol and phosphatidyl inositol mannosides as the major polar lipids. The phylogenetic/phylogenomic analyses based on 16S rRNA gene and genomic sequence comparison revealed that the four strains belong to the genus
Gordonia
, most closely related to
G. neofelifaecis
NRRL B-59395
T
(98.2–98.3% sequence similarity) on the EzBioCloud database. The G+C contents of strains HY002
T
and HY366
T
based on genomic DNA were 66.5 and 66.9%, respectively. The DNA–DNA relatedness values between the two types strains and members of the genus
Gordonia
were far below 70 % (18.6–23.1 %). All genotypic and phenotypic data indicated that the four strains are representatives of two novel separate species, for which the names
Gordonia zhenghanii
sp. nov. and
Gordonia liuliyuniae
sp. nov. are proposed, with HY002
T
(=CGMCC 4 7757
T
=JCM 34 878
T
) and HY366
T
(=CGMCC 1 19146
T
=JCM 34 879
T
) as the respective type strains.
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