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In this article, a classical predator–prey system with linear cross-diffusion and Holling-II type functional response and subject to homogeneous Neuamnn boundary condition is considered. The spatially homogeneous Hopf bifurcation curve and Turing bifurcation curve of the constant coexistence equilibrium are established with the help of the linearized analysis. When the bifurcation parameters are restricted to the Turing instability region and near the Turing bifurcation curve, the associated amplitude equations of the original system near the constant coexistence equilibrium are obtained by means of multiple-scale time perturbation analysis. According to the obtained amplitude equations, the stability and classification of spatiotemporal patterns of the original system near the constant coexistence equilibrium are determined. It is shown that the cross-diffusion in the classical predator–prey system plays an important role in formation of spatiotemporal patterns. Also, the theoretical results are verified numerically. [ABSTRACT FROM AUTHOR]

Myocardial infarction (MI) is a lethal cardiovascular disease worldwide. Emerging evidence has revealed the critical role of gut dysbiosis and impaired gut-brain axis in the pathological progression of MI. Tanshinone IIA (Tan IIA), a traditional Chinese medicine, has been demonstrated to exert therapeutic effects for MI. However, the effects of Tan IIA on gut-brain communication and its potential mechanisms post-MI are still unclear. In this study, we initially found that Tan IIA significantly reduced myocardial inflammation, apoptosis and fibrosis, therefore alleviating hypertrophy and improving cardiac function following MI, suggesting the cardioprotective effect of Tan IIA against MI. Additionally, we observed that Tan IIA improved the gut microbiota as evidenced by changing the α-diversity and β-diversity, and reduced histopathological impairments by decreasing inflammation and permeability in the intestinal tissues, indicating the substantial improvement of Tan IIA in gut function post-MI. Lastly, Tan IIA notably reduced lipopolysaccharides (LPS) level in serum, inflammation responses in paraventricular nucleus (PVN) and sympathetic hyperexcitability following MI, suggesting that restoration of Tan IIA on MI-induced brain alterations. Collectively, these results indicated that the cardioprotective effects of Tan IIA against MI might be associated with improvement in gut-brain axis, and LPS might be the critical factor linking gut and brain. Mechanically, Tan IIA-induced decreased intestinal damage reduced LPS release into serum, and reduced serum LPS contributes to decreased neuroinflammation with PVN and sympathetic inactivation, therefore protecting the myocardium against MI-induced injury. [ABSTRACT FROM AUTHOR]

Recently, nanozyme has found wide applications in various fields such as colorimetric sensors, biomedicine, and the environment. However, the development of highly active and multifunctional nanozyme remains a challenge. Herein, rod-shaped Co3O4/CeO2 heterostructure nanozyme was fabricated through a two-step method comprising a hydrothermal and mechanical grinding process. This method enables efficient creating of well-defined nanocomposite interfaces, resulting abundant oxygen vacancies in the Co3O4/CeO2 heterostructure, as evidenced by high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, and Raman spectroscopy characterizations. Benefiting from the above characteristics, Co3O4/CeO2 heterostructure exhibits peroxidase-mimicking activity and excellent catalytic performance. Therefore, a colorimetric sensor was constructed for the fast and sensitive quantitative analysis of tannic acid with good linearity in the range of 0.05–3.0 μM and a low detection limit of 29.8 nM. Furthermore, Co3O4/CeO2 nanozyme also shows remarkable efficiency in degrading the pollutant rhodamine B, achieving nearly complete degradation within 20 min. The findings spotlight the potential of highly active nanozymes for environmental sensing and remediation applications, emphasizing the importance of interface engineering in heterogeneous nanostructures to enhance their catalytic performance. [ABSTRACT FROM AUTHOR]

Immune checkpoint inhibitor (ICI)-induced myocarditis involves intensive immune/inflammation activation; however, its molecular basis is unclear. Here, we show that gasdermin-E (GSDME), a gasdermin family member, drives ICI-induced myocarditis. Pyroptosis mediated by GSDME, but not the canonical GSDMD, is activated in myocardial tissue of mice and cancer patients with ICI-induced myocarditis. Deficiency of GSDME in male mice alleviates ICI-induced cardiac infiltration of T cells, macrophages, and monocytes, as well as mitochondrial damage and inflammation. Restoration of GSDME expression specifically in cardiomyocytes, rather than myeloid cells, in GSDME-deficient mice reproduces ICI-induced myocarditis. Mechanistically, quantitative proteomics reveal that GSDME-dependent pyroptosis promotes cell death and mitochondrial DNA release, which in turn activates cGAS-STING signaling, triggering a robust interferon response and myocardial immune/inflammation activation. Pharmacological blockade of GSDME attenuates ICI-induced myocarditis and improves long-term survival in mice. Our findings may advance the understanding of ICI-induced myocarditis and suggest that targeting the GSDME-cGAS-STING-interferon axis may help prevent and manage ICI-associated myocarditis. One-sentence summary: GSDME inflames ICI-associated myocarditis. ICI-induced myocarditis is fatal, but its mechanism is unclear. Here, the authors identify GSDME as a key driver by promoting cGAS-STING signaling, enhancing our understanding of its pathogenesis. [ABSTRACT FROM AUTHOR]

Low productivity, high cost, and imbalance between swelling behavior and mechanical properties have limited extensive applications of bacterial cellulose pellicles (BCPs). To remove the drawbacks, two-step fermentation and in-situ modification of chitosan oligosaccharide (COS) were jointly used to improve the yield and mechanical properties of BCPs in this work. Based on the optimization of the culture components, a higher yield of 5.5 g/L, which is 1.9-fold of the control produced under static fermentation, was achieved at the agitation speed of 220 rpm for 3 h (total incubation time 10 d), revealing that high agitation speed in the early incubation can promote BCP production and shorten the production time. In-situ addition of COS can induce the self-assembly of bacterial nanofibers to form a compact network of BCPs through intermolecular H-bond instead of intramolecular H-bond, increasing the yield and mechanical properties. The yield increased to 10.8 g/L, approximately 2.0-fold that of the control. The Young's modulus, toughness, yield strength, and resilience of BCP were increased by 5.7, 2.9, 3.1, and 4.0 folds, respectively. COS modification significantly improved BCP production and balanced the swelling behavior and mechanical properties, which removed the drawbacks of BCP production to a certain degree and would promote an extensive application of BCPs. [ABSTRACT FROM AUTHOR]

Senescence of vascular smooth muscle cells (VSMCs) contributes to aging-related cardiovascular diseases by promoting arterial remodelling and stiffness. Ferroptosis is a novel type of regulated cell death associated with lipid oxidation. Here, we show that pro-ferroptosis signaling drives VSMCs senescence to accelerate vascular NAD+ loss, remodelling and aging. Pro-ferroptotic signaling is triggered in senescent VSMCs and arteries of aged mice. Furthermore, the activation of pro-ferroptotic signaling in VSMCs not only induces NAD+ loss and senescence but also promotes the release of a pro-senescent secretome. Pharmacological or genetic inhibition of pro-ferroptosis signaling, ameliorates VSMCs senescence, reduces vascular stiffness and retards the progression of abdominal aortic aneurysm in mice. Mechanistically, we revealed that inhibition of pro-ferroptotic signaling facilitates the nuclear-cytoplasmic shuttling of proliferator-activated receptor-γ and, thereby impeding nuclear receptor coactivator 4-ferrtin complex-centric ferritinophagy. Finally, the activated pro-ferroptotic signaling correlates with arterial stiffness in a human proof-of-concept study. These findings have significant implications for future therapeutic strategies aiming to eliminate vascular ferroptosis in senescence- or aging-associated cardiovascular diseases. Ferroptosis is a novel form of regulated cell death associated with lipid oxidation. Here, the authors demonstrate that the proferroptosis signal is activated and drives vascular aging by inducing senescence in vascular smooth muscle cells. [ABSTRACT FROM AUTHOR]

When cells proliferate, stress on DNA replication or exposure to endogenous or external insults frequently results in DNA damage. DNA-Damage Response (DDR) networks are complex signaling pathways used by multicellular organisms to prevent DNA damage. Depending on the type of broken DNA, the various pathways, Base-Excision Repair (BER), Nucleotide Excision Repair (NER), Mismatch Repair (MMR), Homologous Recombination (HR), Non-Homologous End-Joining (NHEJ), Interstrand Crosslink (ICL) repair, and other direct repair pathways, can be activated separately or in combination to repair DNA damage. To preserve homeostasis, innate and adaptive immune responses are effective defenses against endogenous mutation or invasion by external pathogens. It is interesting to note that new research keeps showing how closely DDR components and the immune system are related. DDR and immunological response are linked by immune effectors such as the cyclic GMP-AMP synthase (cGAS)–Stimulator of Interferon Genes (STING) pathway. These effectors act as sensors of DNA damage-caused immune response. Furthermore, DDR components themselves function in immune responses to trigger the generation of inflammatory cytokines in a cascade or even trigger programmed cell death. Defective DDR components are known to disrupt genomic stability and compromise immunological responses, aggravating immune imbalance and leading to serious diseases such as cancer and autoimmune disorders. This study examines the most recent developments in the interaction between DDR elements and immunological responses. The DDR network’s immune modulators’ dual roles may offer new perspectives on treating infectious disorders linked to DNA damage, including cancer, and on the development of target immunotherapy. [ABSTRACT FROM AUTHOR]

Purpose: Currently, there are multiple active clinical trials involving poly(ADP-ribose) polymerase (PARP) inhibitors in the treatment of glioblastoma. The noninvasive quantification of baseline PARP expression using positron emission tomography (PET) may provide prognostic information and lead to more precise treatment. Due to the lack of brain-penetrant PARP imaging agents, the reliable and accurate in vivo quantification of PARP in the brain remains elusive. Herein, we report the synthesis of a brain-penetrant PARP PET tracer, (R)-2-(2-methyl-1-(methyl-11C)pyrrolidin-2-yl)-1H-benzo[d]imidazole-4-carboxamide ([11C]PyBic), and its preclinical evaluations in a syngeneic RG2 rat glioblastoma model and healthy nonhuman primates. Methods: We synthesized [11C]PyBic using veliparib as the labeling precursor, performed dynamic PET scans on RG2 tumor-bearing rats and calculated the distribution volume ratio (DVR) using simplified reference region method 2 (SRTM2) with the contralateral nontumor brain region as the reference region. We performed biodistribution studies, western blot, and immunostaining studies to validate the in vivo PET quantification results. We characterized the brain kinetics and binding specificity of [11C]PyBic in nonhuman primates on FOCUS220 scanner and calculated the volume of distribution (VT), nondisplaceable volume of distribution (VND), and nondisplaceable binding potential (BPND) in selected brain regions. Results: [11C]PyBic was synthesized efficiently in one step, with greater than 97% radiochemical and chemical purity and molar activity of 148 ± 85 MBq/nmol (n = 6). [11C]PyBic demonstrated PARP-specific binding in RG2 tumors, with 74% of tracer binding in tumors blocked by preinjected veliparib (i.v., 5 mg/kg). The in vivo PET imaging results were corroborated by ex vivo biodistribution, PARP1 immunohistochemistry and immunoblotting data. Furthermore, brain penetration of [11C]PyBic was confirmed by quantitative monkey brain PET, which showed high specific uptake (BPND > 3) and low nonspecific uptake (VND < 3 mL/cm3) in the monkey brain. Conclusion: [11C]PyBic is the first brain-penetrant PARP PET tracer validated in a rat glioblastoma model and healthy nonhuman primates. The brain kinetics of [11C]PyBic are suitable for noninvasive quantification of available PARP binding in the brain, which posits [11C]PyBic to have broad applications in oncology and neuroimaging. [ABSTRACT FROM AUTHOR]

Purpose: To quantify the synaptic vesicle glycoprotein 2A (SV2A) changes in the whole central nervous system (CNS) under pathophysiological conditions, a high affinity SV2A PET radiotracer with improved in vivo stability is desirable to minimize the potential confounding effect of radiometabolites. The aim of this study was to develop such a PET tracer based on the molecular scaffold of UCB-A, and evaluate its pharmacokinetics, in vivo stability, specific binding, and nonspecific binding signals in nonhuman primate brains, in comparison with [11C]UCB-A, [11C]UCB-J, and [18F]SynVesT-1. Methods: The racemic SDM-16 (4-(3,5-difluorophenyl)-1-((2-methyl-1H-imidazol-1-yl)methyl)pyrrolidin-2-one) and its two enantiomers were synthesized and assayed for in vitro binding affinities to human SV2A. We synthesized the enantiopure [18F]SDM-16 using the corresponding enantiopure arylstannane precursor. Nonhuman primate brain PET scans were performed on FOCUS 220 scanners. Arterial blood was drawn for the measurement of plasma free fraction (fP), radiometabolite analysis, and construction of the plasma input function. Regional time-activity curves (TACs) were fitted with the one-tissue compartment (1TC) model to obtain the volume of distribution (VT). Nondisplaceable binding potential (BPND) was calculated using either the nondisplaceable volume of distribution (VND) or the centrum semiovale (CS) as the reference region. Results: SDM-16 was synthesized in 3 steps with 44% overall yield and has the highest affinity (Ki = 0.9 nM) to human SV2A among all reported SV2A ligands. [18F]SDM-16 was prepared in about 20% decay-corrected radiochemical yield within 90 min, with greater than 99% radiochemical and enantiomeric purity. This radiotracer displayed high specific binding in monkey brains and was metabolically more stable than the other SV2A PET tracers. The fP of [18F]SDM-16 was 69%, which was higher than those of [11C]UCB-J (46%), [18F]SynVesT-1 (43%), [18F]SynVesT-2 (41%), and [18F]UCB-H (43%). The TACs were well described with the 1TC. The averaged test–retest variability (TRV) was 7 ± 3%, and averaged absolute TRV (aTRV) was 14 ± 7% for the analyzed brain regions. Conclusion: We have successfully synthesized a novel SV2A PET tracer [18F]SDM-16, which has the highest SV2A binding affinity and metabolical stability among published SV2A PET tracers. The [18F]SDM-16 brain PET images showed superb contrast between gray matter and white matter. Moreover, [18F]SDM-16 showed high specific and reversible binding in the NHP brains, allowing for the reliable and sensitive quantification of SV2A, and has potential applications in the visualization and quantification of SV2A beyond the brain. [ABSTRACT FROM AUTHOR]

A two-dimensional Green's function suitable for a coated isotropic thermoelastic semi-infinite plane with a line heat source above the surface has been obtained using the method of images. Firstly, based on the control equations of the isotropic thermoelastic materials and the two-dimensional heat conduction equations, the general solutions to three harmonic functions have been obtained. Secondly, six potential function equations have been acquired using the method of images. Finally, three equations that are expressed by three harmonic functions have been obtained by substituting six series of harmonic functions into the boundary conditions of the coated surface. In this way, nine recursive equations have been determined. By taking Green's function of the isotropic semi-infinite thermoelastic plane with a line heat source above the surface as the first term, the thermoelastic coupling field for the coated semi-infinite plane has been calculated using the recursive formula. The interface temperature increment component and the interface stress components of the coating structures have been calculated numerically. By analyzing the thermal stress of different coated materials, valuable conclusions such as the interface effect, tensile failure, and shear delamination have been obtained, which can provide a reliable basis for the design and analysis of thermal barrier coating structures. [ABSTRACT FROM AUTHOR]

The key to the coordination of photovoltaic power generation and conventional energy power load lies in the accurate prediction of photovoltaic power generation. At present, prediction models have problems with accuracy and system operation stability. Based on the neural network algorithm, this research carries the prediction of energy photovoltaic power generation and establishes a BP neural network prediction model and a wavelet neural network prediction model. Moreover, this research studies the influence of various factors on the prediction t of photovoltaic power generation, and analyzes the relationship between the various factors. In addition, in this study, a comparative test is constructed to analyze the model performance, and a statistical graph is drawn to take a visual comparison of performance. The research shows that the model proposed in this paper has certain effects and has certain advantages in the prediction of photovoltaic power generation. [ABSTRACT FROM AUTHOR]

In this paper, we present the application of a new method measuring Hubble parameter H(z) by using the anisotropy of luminosity distance ( d L ) of the gravitational wave (GW) standard sirens of neutron star (NS) binary system. The method has never been put into practice so far due to the lack of the ability of detecting GW. However, LIGO's success in detecting GW of black hole (BH) binary system merger announced the potential possibility of this new method. We apply this method to several GW detecting projects, including Advanced LIGO (aLIGO), Einstein Telescope (ET) and DECIGO, and evaluate its constraint ability on cosmological parameters of H(z). It turns out that the H(z) by aLIGO and ET is of bad accuracy, while the H(z) by DECIGO shows a good one. We simulate H(z) data at every 0.1 redshift span using the error information of H(z) by DECIGO, and put the mock data into the forecasting of cosmological parameters. Compared with the previous data and method, we get an obviously tighter constraint on cosmological parameters by mock data, and a concomitantly higher value of Figure of Merit (FoM, the reciprocal of the area enclosed by the 2 σ confidence region). For a 3-year-observation by standard sirens of DECIGO, the FoM value is as high as 170.82. If a 10-year-observation is launched, the FoM could reach 569.42. For comparison, the FoM of 38 actual observed H(z) data (OHD) is 9.3. We also investigate the undulant universe, which shows a comparable improvement on the constraint of cosmological parameters. These improvement indicates that the new method has great potential in further cosmological constraints. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Zhejiang University: Science B is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The storage and transportation of raw milk at low temperatures promote the growth of psychrotrophic bacteria and the production of thermo-stable enzymes, which pose great threats to the quality and shelf-life of dairy products. Though many studies have been carried out on the spoilage potential of psychrotrophic bacteria and the thermo-stabilities of the enzymes they produce, further detailed studies are needed to devise an effective strategy to avoid dairy spoilage. The purpose of this study was to explore the spoilage potential of psychrotrophic bacteria from Chinese raw milk samples at both room temperature (28 °C) and refrigerated temperature (7 °C). Species of Yersinia, Pseudomonas, Serratia, and Chryseobacterium showed high proteolytic activity. The highest proteolytic activity was shown by Yersinia intermedia followed by Pseudomonas fluorescens (d). Lipolytic activity was high in isolates of Acinetobacter, and the highest in Acinetobacter guillouiae. Certain isolates showed positive β-galactosidase and phospholipase activity. Strains belonging to the same species sometimes showed markedly different phenotypic characteristics. Proteases and lipases produced by psychrotrophic bacteria retained activity after heat treatment at 70, 80, or 90 °C, and proteases appeared to be more heat-stable than lipases. For these reasons, thermo-stable spoilage enzymes produced by a high number of psychrotrophic bacterial isolates from raw milk are of major concern to the dairy industry. The results of this study provide valuable data about the spoilage potential of bacterial strains in raw milk and the thermal resistance of the enzymes they produce. [ABSTRACT FROM AUTHOR]

Docosahexaenoic acid (DHA) is enriched in membrane phospholipids of the central nervous system (CNS) and has a role in aging and neuropsychiatric disorders. DHA is metabolized by the enzyme Alox15 to 17S-hydroxy-DHA, which is then converted to 7S-hydroperoxy,17S-hydroxy-DHA by a 5-lipoxygenase, and thence via epoxy intermediates to the anti-inflammatory molecule, resolvin D1 (RvD1 or 7S,8R,17S-trihydroxy-docosa-Z,9E,11E,13Z,15E,19Z-hexaenoic acid). In this study, we investigated the distribution and function of Alox15 in the CNS. RT-PCR of the CNS showed that the prefrontal cortex exhibits the highest Alox15 mRNA expression level, followed by the parietal association cortex and secondary auditory cortex, olfactory bulb, motor and somatosensory cortices, and the hippocampus. Western blot analysis was consistent with RT-PCR data, in that the prefrontal cortex, cerebral cortex, hippocampus, and olfactory bulb had high Alox15 protein expression. Immunohistochemistry showed moderate staining in the olfactory bulb, cerebral cortex, septum, striatum, cerebellar cortex, cochlear nuclei, spinal trigeminal nucleus, and dorsal horn of the spinal cord. Immuno-electron microscopy showed localization of Alox15 in dendrites, in the prefrontal cortex. Liquid chromatography mass spectrometry analysis showed significant decrease in resolvin D1 levels in the prefrontal cortex after inhibition or antisense knockdown of Alox15. Alox15 inhibition or antisense knockdown in the prefrontal cortex also blocked long-term potentiation of the hippocampo-prefrontal cortex pathway and increased errors in alternation, in the T-maze test. They indicate that Alox15 processing of DHA contributes to production of resolvin D1 and LTP at hippocampo-prefrontal cortical synapses and associated spatial working memory performance. Together, results provide evidence for a key role of anti-inflammatory molecules generated by Alox15 and DHA, such as resolvin D1, in memory. They suggest that neuroinflammatory brain disorders and chronic neurodegeneration may ‘drain’ anti-inflammatory molecules that are necessary for normal neuronal signaling, and compromise cognition. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Zhejiang University: Science B is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Stroke is a serious disease with complex pathomechanism and limited therapeutic effect in clinic. Our previous research has found obvious therapeutic effect of Puerarin (Pur) on stroke injury of rat. The aim of this study is to investigate the transcriptome changes of oxygen-glucose deprivation/reoxygenation (OGD/R)-injured astrocytes before and after the intervention of Pur. Cells activity and apoptosis detection indicated that the activity of OGD/R-injured astrocytes was improved, and the apoptosis was ameliorated by Pur. Affymetrix GeneChip Rat Genome 230 2.0 Array assays indicated that after intervention of Pur, mRNA expressions of 31 genes were up-regulated and 40 genes were down-regulated in OGD group, whereas mRNA expression of 36 genes were up-regulated, and 88 genes were down-regulated in OGD/R group. Pathway analysis indicated that the olfactory transduction pathway and the JAK (janus kinase) 2/STAT (signal transducer and activator of transcription) three pathways were down-regulated by Pur during OGD/R injury of astrocytes. These data indicated that Pur regulates transcriptome and expresses protective effect on astrocytes during OGD/R injury, and may be a potential therapeutic agent for the treatment of stroke. [ABSTRACT FROM AUTHOR]

This present paper focus on transcriptome changes of astrocytes before and after oxygen glucose deprivation (OGD) injury. Cortical astrocytes of Sprague-Dawley (SD) rats were cultured in OGD condition for 6 h, and the damage of cells was analyzed by cell's activity detection, lactate dehydrogenase leakage rate detection, annexin V-FITC (fluorescein isothiocyanate)/PI (propidium iodide) apoptosis detection, and transcriptome change detection through Affymetrix GeneChip Rat Genome 230 2.0 Array; some regulated genes were detected by quantitative real-time polymerase chain reaction (qPCR). After OGD injury, activity of astrocytes was decreased, and apoptosis of injured cells was increased. mRNA expressions of 404 genes were upregulated and 454 genes were downregulated, including upregulation of MAPK signal pathway and downregulation of PI3k/Akt pathway. Otherwise, pathways of the focal adhesion (percentage of all regulated genes, 11.4 %), HIF-1 (10.2 %), and one carbon pool by folate (3.4 %), etc. were upregulated, and steroid biosynthesis (7 %), basal cell carcinoma (9.9 %), and terpenoid backbone (5.6 %), etc. were down-regulated. These results indicate that apoptosis of astrocytes induced by OGD injury is associated with the MAPK and PI3k/Akt pathways. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Zhejiang University: Science B is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: Transfacet screws have been used as an alternative posterior fixation in the cervical spine. There is lack of spinal stability of the transfacet screws either as stand-along constructs or combined with anterior plate. This study was designed to evaluate spinal stability of transfacet screws following posterior ligamentous injury and combined with anterior plate, respectively, and compare transfacet screws to lateral mass screw-rod constructs.Methods: Flexibility tests were conducted on eight cadaveric specimens in an intact and injury, and instrumented with the transfacet screw fixation and lateral mass screw-rod construct at C5-C7 levels either after section of the posterior ligamentous complex or combined with an anterior plate and a mesh cage for C6 corpectomy reconstruction. A pure moment of ±2.0 Nm was applied to the specimen in flexion-extension, lateral bending, and axial rotation. Ranges of motion (ROM) were calculated for the C5-C7 segment.Results: ROM with the transfacet screws was 22 % of intact in flexion-extension, 9 % in lateral bending and 11 % in axial rotation, while ROM with the lateral mass screw-rod construct was 9 % in flexion-extension, 8 % in lateral bending and 22 % in axial rotation. The only significant difference between two constructs was seen in flexion-extension (5.8 ± 4.2° vs. 2.4 ± 1.2°, P = 0.002). When combined with an anterior plate and mesh cage, the transfacet screw fixation reduced ROM to 3.0° in flexion-extension, 1.2° in lateral bending, and 1.1° in axial rotation, which was similar to the lateral mass screw-rod construct.Conclusions: This study identified the transfacet screw fixation, as stand-alone posterior fixation, was equivalent to the lateral mass screw-rod constructs in axial rotation and lateral bending except in flexion-extension. When combined with an anterior plate, the transfacet screw fixation was similar to the lateral mass screw-rod construct in motion constraint. The results suggested the transfacet screw fixation a biomechanically effective way as supplementation of anterior fixation. [ABSTRACT FROM AUTHOR]

Graphene/polyaniline (GN/PANI) composites were synthesized by in situ polymerization with the assistance of poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (P123). We show that the addition of P123 enhanced the wettability of GN and hence improved its uniformity in aqueous solution and the dispersity of PANI loaded on GN surface. Structural and morphological analyses indicate that GN has been successfully coated with PANI. P123 was mainly acted as soft temples to improve the control of morphology and increase composites effective specific surface area. Furthermore, it can improve composites capacitive performance as evidenced by electrochemical tests. When the molar ratio of P123 to ANI is 0.0108, the composites exhibit the best performance, in terms of the rate capability, the lowest equivalent series resistance (0.31 Ω) and the charge-transfer resistance (1.46 Ω). Additionally, it achieves a capacity retention of 91.8 % after 1000 charge-discharge cycles at the current density of 500 mA g, an increase of 82 % over the composites without P123. A mechanism for interactions of P123, GN, and PANI is proposed in this work. [ABSTRACT FROM AUTHOR]

Purpose: In unique clinical situations where C1-C2 anterior transarticular screw (ATS) fixation is not available or has failed, an anterior transarticular crossing screw (ATCS) with transcorporal pathway of the screws inside the contralateral promontory of C2 may enhance the stabilization and achieve atlantoaxial arthrodesis. The present study was to describe a novel technique of ATCS fixation for atlantoaxial joint instability and its applied anatomy, and compared it with ATS fixation method.Methods: Direct measurements using digital calipers and a goniometer were conducted on 30 pairs of dried human C1 and C2 vertebrae. The ATS and ATCS with screws (Φ 4.0 mm) were performed on 11 fresh cervical spine specimens. The screw lengths in the C1 and C2, and screw entry angles of the ATS and ATCS were measured, respectively. Cadaver specimens were dissected to observe the incidence of violation to the important structures surrounding the ATS and ATCS fixation technique.Results: There was enough osseous space for ATCS placement. The lateral and incline angle of the ATCS was 36.2° and 28.7°, respectively. Screw purchase in C2 of the ATCS (25.6 mm) was greater than that of the ATS (11.4 mm). The ATCS C1 purchase (14.8 mm) was similar to the ATS C1 purchase (14.9 mm). No violation to the vertebral artery groove, the spinal canal or the atlanto-occipital joint was observed after the ATCS placement.Conclusion: Anterior transarticular crossing screw is a feasible and viable option for atlantoaxial fixation in selected cases. This technique achieved remarkable longer screw purchase and could enhance the atlantoaxial stability. [ABSTRACT FROM AUTHOR]

Background and aims: Belowground interactions can greatly modify fine root (≤2 mm in diameter) traits to increase soil resource acquisition for tree growth. We examined how mixed forests alter fine root traits compared to pure forests. Methods: A pseudo-experimental tree cluster design was used to select small-area plots of single and mixed species in a Pinus massoniana- Lithocarpus glaber (PM-LG) forest and a L. glaber- Cyclobalanopsis glauca (LG-CG) forest. In each plot, soil cores were sampled down to 30 cm at a 0.5 m interval between target and neighbouring trees. Fine roots in soil cores were then divided by species to determine biomass and morphological traits. Results: The mixed PM-LG plots exhibited significantly higher fine root biomass while the mixed LG-CG plots had no significant differences in fine root biomass compared to their respective pure plots. In pure plots, P. massoniana had higher fine root biomass and lower specific root length (SRL) and specific root area (SRA) than L. glaber, whereas fine root traits were similar for L. glaber and C. glauca. Compared with pure plots for a given species, fine root biomass in the entire soil profile decreased for P. massoniana but increased for L. glaber in mixed PM-LG plots. In mixed LG-CG plots, fine root biomass decreased for each species at all soil depths. Conclusions: Whether positive interactions of fine roots occur is dependent on tree species composition. Fine root biomass was greater in mixed forests where tree species showed contrasting growth strategies and root traits, such as PM-LG forests, thus suggesting positive interactions. [ABSTRACT FROM AUTHOR]

Purpose: A fabricated mesh cage and/or posterior occipitocervical instrumentation alone has been used for reconstruction of ventral defect of the upper cervical spine. However, using a trimmed mesh cage it was hard to achieve optimal clival screw purchase and it migrated or broke. A specific instrumentation at the craniovertebral junction (CVJ) should incorporate the morphology of the CVJ and biomechanical validation. The purpose of the present study was to develop an innovative clivus plate integrated with the clinical anatomy of CVJ and to evaluate the stability of the clivus plate fixation (CPF), stand-alone or combined with a posterior occipitocervical fixation (POCF). Methods: Dimensions relevant to the clivus plate were measured on 40 adult dry bones and CT images of 30 patients. The CPF was composed of the clivus plate and a titanium mesh cage. The clivus plate was anchored to the clivus, atlas and C3 body and connected to the mesh cage. Six fresh cadaveric head-neck specimens (Oc-C4) were used in this study (46 ± 15 years old, 2 F/4 M). A continuous pure moment of ±1.5 Nm was applied to the specimen in flexion, extension, lateral bending and axial rotation. The status of intact, CPF alone, and CPF plus POCF was tested on each specimen. The CPF was implanted to the specimen following resection of the C1 anterior arch, C2 vertebral body, C2-C3 disc and atlantoaxial ligaments. The POCF was applied with screws anchoring at the occiput, C1, C3 and C4. The range of motion (ROM) and neutral zone (NZ) from the occiput to C3 were calculated. Results: The clivus plate was developed based on measurements of 40 adult dry bones and CT images of 30 patients. The plates were successfully applied to all specimens. No obvious loosening or mismatch was observed. The mean clival length and widest and narrowest diameter of the clivus were 26, 33 and 19 mm, respectively. The clivus screw length was 8 mm for the caudal holes and 10 mm for the cephalad hole. The CPF reduced ROMs to 3.9° in flexion, 2.8° in extension, 4.2° in lateral bending and 6.8° in axial rotation. The combined CPF and POCF constrained motion within 0.6° in all directions and more than the CPF ( P < 0.05). NZs after the CPF were 1.0° in flexion-extension, 2.1° in lateral bending and 2.2° in axial rotation, respectively. NZs after the CPF plus POCF were within 0.2° in all directions and less than the CPF ( P < 0.05). Conclusion: This study demonstrated screw purchase in the adult clivus and developed an innovative clivus plate fixation for reconstructing an extensive ventral defect in the upper cervical spine. The clivus plate fixation combined a posterior instrumentation ensuring reliable upper cervical stability. [ABSTRACT FROM AUTHOR]

An open-cell metallic foam was employed as an analogue material for human trabecular bone to interface with polymethyl methacrylate (PMMA) bone cement to produce composite foam-cement interface specimens. The stress-displacement curves of the specimens were obtained experimentally under tension, shear, mixed tension and shear (mixed-mode), and step-wise compression loadings. In addition, under step-wise compression, an image-guided failure assessment (IGFA) was used to monitor the evolution of micro-damage of the interface. Microcomputed tomography (µCT) images were used to build a subject-specific model, which was then used to perform finite element (FE) analysis under tension, shear and compression. For tension-shear loading conditions, the strengths of the interface specimens were found to increase with the increase of the loading angle reaching the maximum under shear loading condition, and the results compare reasonably well with those from bone-cement interface. Under compression, however, the mechanical strength measured from the foam-cement interface is much lower than that from bone-cement interface. Furthermore, load transfer between the foam and the cement appears to be poor under both tension and compression, hence the use of the foam should be discouraged as a bone analogue material for cement fixation studies in joint replacements. [ABSTRACT FROM AUTHOR]

Based on the two-dimensional steady-state governing equations of isotropic thermoelastic material and the compact general solution expressed in three harmonic functions, the corresponding three harmonic functions contain nine undetermined constants are constructed for a line heat source applied in the interior of a semi-infinite thermoelastic plane. All components of thermoelastic field in the semi-infinite plane can be derived by substituting the harmonic functions into the general solution. And the undetermined constants can be obtained by the compatibility conditions, equilibrium conditions and the different boundary conditions for extended Mindlin problem and extended Lorentz problem. Thus, the Green’s functions in above two cases are obtained, and the numerical results are given graphically by contours. [ABSTRACT FROM AUTHOR]

A nonlinear lateral-torsional coupled vibration model of a planetary gear system was established by taking transmission errors, time varying meshing stiffness and multiple gear backlashes into account. The bifurcation diagram of the system's motion state with rotational speed of sun gear was conducted through four steps. As a bifurcation parameter, the effect of rotational speed on the bifurcation properties of the system was assessed. The study results reveal that periodic motion is the main motion state of planetary gear train in low speed region when n<2 350 r/min, but chaos motion state is dominant in high speed region when n>2 350 r/min, The way of periodic motion to chaos is doubling bifurcation. There are two kinds of unstable modes and nine unstable regions in the speed region when 1 000 r/min n<3 000 r/min. [ABSTRACT FROM AUTHOR]

The universe with adiabatic matter creation is considered. It is thought that the negative pressure caused by matter creation can play the role of a dark energy component, and drive the accelerating expansion of the universe. Using the Type Ia supernovae (SNe Ia) data, the observational Hubble parameter data, the Cosmic Microwave Background (CMB) data and the Baryonic Acoustic Oscillation (BAO) data, we make constraints on the cosmological parameters, assuming a spatially flat universe. Our results show that the model with matter creation is consistent with the SNe Ia data, while the joint constraints of all these observational data disfavor this model. If the cosmological constant is taken into account, a traditional model without matter creation is favored by the joint observations. [ABSTRACT FROM AUTHOR]

Repair of superficial damage to gastrointestinal mucosa occurs by a process called restitution. Goblet cells reside throughout the length of the intestine and are responsible for the production of mucus. However, a kinetic analysis of goblet cell dynamics of small intestine in restitution has hitherto not been reported. The aim of the present study was to investigate the role of goblet cells in the process of restitution of rat small intestine subjected to ischemia and ischemia-reperfusion injury, and therefore intestinal epithelium from rats subjected to both ischemia and ischemia-reperfusion was studied. Detachment of enterocytes was observed after 5-min of reperfusion. After 20-30 minutes of reperfusion, the denuded villous tips were covered with goblet cells. Within 75 min of reperfusion the epithelium restitution was complete. On the other hand, restitution was not observed in ischemia group. These data suggest that goblet cells may play an important role in restitution after ischemia-reperfusion injury. [ABSTRACT FROM AUTHOR]

By forming the square root of the Wheeler-DeWitt equation and applying itto a minisuperspace composed of a Kantowski-Sachs universe, we derive acosmological wave function with conserved current and positive-definiteprobability density. [ABSTRACT FROM AUTHOR]

Derives the equation of the acoustic nonlinearity parameter in organic liquid binary mixtures. Parameter B/A and Jacobson's molecular free length theory in liquids; Equation of acoustic nonlinearity parameter B/A in the liquid binary mixtures; Results and discussion.

Quantum cosmology with a complex φ4 fieldat finite temperature for the Vilenkin boundarycondition and the Hartle-Hawking boundary condition isstudied. The Euclidean region in minisuperspace isgenerally bounded by a closed curve. The wave function ofthe universe calculated in the WKB approximation cancross, through scattering or tunneling, from the initialclassically allowed region to the final classically allowed region. For a given value of scalarfield, the probability density for the Vilenkin boundarycondition is smallest at zero temperature, and whentemperature increases, the probability density rises remarkably. At the same time, the oppositeresults are given for Hartle-Hawking boundary condition.In addition, the classical trajectories of the universeare calculated in detail. [ABSTRACT FROM AUTHOR]

Gravitational waves (GWs) from extra dimensions, very early universe, and some high-energy astrophysical processes might have at most six polarization states: tensor- and nontensor-mode gravitons. The peak regions or partial peak regions (of the amplitudes or energy densities) of some of such GWs are just distributed in the GHz or higher frequency band, which would be an optimal frequency band for the electromagnetic (EM) response to such high-frequency GWs (HFGWs). In this paper we investigate the EM response to the HFGWs, and for the first time we obtain the concrete form of analytic solutions of the perturbative EM fields caused by all six possible polarizations of the HFGWs in the background stable EM fields and in the proposed three dimensional synchro-resonance system (3DSR system), respectively. It is found that all such six polarizations may in principle show separability and detectability. Moreover, the detection frequency band ( ∼ 10 8 to 10 12 Hz or higher) of the signal photon fluxes by the 3DSR system and the observation frequency range ( ∼ 7 × 10 7 to 3 × 10 9 Hz) of the signals by the FAST (Five-hundred-meter Aperture Spherical Telescope, China) have a certain overlapping property, and thus their coincidence experiments in the future for observations will have high complementarity. [ABSTRACT FROM AUTHOR]

Aiming at exploring the nature of dark energy (DE), we use forty-three observational Hubble parameter data (OHD) in the redshift range 0 to make a cosmological model-independent test of the ΛCDM model with two-point Omh2(z2;z1) diagnostic. In ΛCDM model, with equation of state (EoS) w=-1, two-point diagnostic relation Omh2≡Ωmh2 is tenable, where Ωm is the present matter density parameter, and h is the Hubble parameter divided by 100 kms-1Mpc-1. We utilize two methods: the weighted mean and median statistics to bin the OHD to increase the signal-to-noise ratio of the measurements. The binning methods turn out to be promising and considered to be robust. By applying the two-point diagnostic to the binned data, we find that although the best-fit values of Omh2 fluctuate as the continuous redshift intervals change, on average, they are continuous with being constant within 1 σ confidence interval. Therefore, we conclude that the ΛCDM model cannot be ruled out. [ABSTRACT FROM AUTHOR]

The spatially averaged inhomogeneous Universe includes a kinematical backreaction term QD that is relate to the averaged spatial Ricci scalar ⟨R⟩D in the framework of general relativity. Under the assumption that QD and ⟨R⟩D obey the scaling laws of the volume scale factor aD, a direct coupling between them with a scaling index n is remarkable. In order to explore the generic properties of a backreaction model for explaining the accelerated expansion of the Universe, we exploit two metrics to describe the late time Universe. Since the standard FLRW metric cannot precisely describe the late time Universe on small scales, the template metric with an evolving curvature parameter κD(t) is employed. However, we doubt the validity of the prescription for κD, which motivates us apply observational Hubble parameter data (OHD) to constrain parameters in dust cosmology. First, for FLRW metric, by getting best-fit constraints of ΩmD0=0.25-0.03+0.03, n=0.02-0.66+0.69, and HD0=70.54-3.97+4.24kms-1Mpc-1, the evolutions of parameters are explored. Second, in template metric context, by marginalizing over HD0 as a prior of uniform distribution, we obtain the best-fit values of n=-1.22-0.41+0.68 and ΩmD0=0.12-0.02+0.04. Moreover, we utilize three different Gaussian priors of HD0, which result in different best-fits of n, but almost the same best-fit value of ΩmD0∼0.12. Also, the absolute constraints without marginalization of parameter are obtained: n=-1.1-0.50+0.58 and ΩmD0=0.13±0.03. With these constraints, the evolutions of the effective deceleration parameter qD indicate that the backreaction can account for the accelerated expansion of the Universe without involving extra dark energy component in the scaling solution context. Nevertheless, the results also verify that the prescription of κD is insufficient and should be improved. [ABSTRACT FROM AUTHOR]