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Besides the normal hearing pathway known as air conduction (AC), sound can also transmit to the cochlea through the skull, known as bone conduction (BC). During BC stimulation, the cochlear walls demonstrate rigid body motion (RBM) and compressional motion (CPM), both inducing the basilar membrane traveling wave (TW). Despite numerous measuring and modeling efforts for the TW phenomenon, the mechanism remains unclear, especially in the case of BC. This paper proposes a 3D finite element cochlea model mimicking the TW under BC. The model uses a traditional "box model" form, but in a spiral shape, with two fluid chambers separated by the long and flexible BM. The cochlear fluid was enclosed by bony walls, the oval and round window membranes. Contingent boundary conditions and stimulations are introduced according to the physical basis of AC and BC. Particularly for BC, both RBM and CPM of the cochlea walls are simulated. Harmonic numerical solutions are obtained at multiple frequencies among the hearing range. The BM vibration amplitude ( U BM ) and its relation with volume displacement difference between the oval and round windows (Δ Vol) , as well as the pressure difference at the base of the cochlea ( P SV 0 - P ST 0 ), are analyzed. The simulated BM response at 12 mm from the base is peaked at about 3 k Hz, which is consistent with published experimental data. The TW properties under AC and BC are the same and have a common mechanism. (1) U BM is proportional to Δ V o l at low frequencies. (2) U BM is also proportional to P SV 0 - P ST 0 , within 5 dB error at high frequencies such as 16 k Hz. This study partly reveals the common quantitative relations between the TW and related factors under AC and BC hearing. [ABSTRACT FROM AUTHOR]

A Gram-staining negative, facultative anaerobic, motile and short rod-shaped bacterium, designated strain yh7-1T, was isolated from rhizosphere soil of Citrus sinenesis collected from the garden of Citrus sinenesis in Ailao Mountain, south-west China. Cells grew at 15–45 °C, pH 5.0–9.0 and were able to tolerate up to 1% (w/v) NaCl on R2A medium. The respiratory lipoquinone was Q-10 and the major cellular fatty acids contained summed feature 8 (C18:1 ω7c or C18:1 ω6c) and C18:0. Polar lipids in the cellular membrane were phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, two unidentified phospholipids and one unidentified aminophospholipid. The genomic DNA G+C content was 69.9 mol%. On basis of 16S rRNA gene sequence analysis, strain yh7-1T showed the highest similarities with Chthonobacter albigriseus KCTC 42450T (97.6%), Mongoliimonas terrestris KCTC 42635T (97.0%) and lower than 97.0% to other species. Phylogenetic trees based on 16S rRNA gene sequences indicated that strain yh7-1T clustered with C. albigriseus KCTC 42450T. The ANI values ranged between 78.1 and 82.7% for C. albigriseus KCTC 42450T, M. terrestris KCTC 42635T and strain yh7-1T, which were lower than the prokaryotic species delineation threshold of 95.0–96.0%. The digital DNA–DNA hybridization values between C. albigriseus KCTC 42450T, M. terrestris KCTC 42635T and strain yh7-1T indicated that the new isolate represents a novel genomic species. According to the phenotypic and genotypic characteristics, strain yh7-1T should belong to the genus Chthonobacter, for which the name Chthonobacter rhizosphaerae sp. nov. (type strain yh7-1T = CGMCC 1.17236T = CCTCC AB 2019258T = KCTC 82185T) is proposed. [ABSTRACT FROM AUTHOR]

A transient three-dimensional powder-scale model was established for understanding the flow field and mass transfer within the molten pool during the selective laser melting (SLM) of Inconel 718 alloy by considering some important physical phenomena, such as, a transition from powder to solid, nonlinearities produced by temperature-dependent materials' properties, and fluid flow in the calculation. The influence of laser power or scanning speed on the flow field and cooling rate was discussed in detail. The simulation results reveal that the motion of molten pool and higher cooling rate promote the mass transfer and benefit the solute distribution by increasing laser power. However, with increasing the scanning speed, the melt flow speed and cooling rate are elevated, resulting in an agglomeration of the solute elements, which is ascribed to the shorter dwelling time of liquid. Therefore, the segregation of Nb can be effectively suppressed by increasing laser power or decreasing scanning speed, which can decrease the dwelling time of liquid. [ABSTRACT FROM AUTHOR]

Increasing use of anaerobically digested swine manure in the farmland makes it necessary to understand its impact on N2O emissions, regarding the source of N2O and the corresponding mechanism of action. We used a 15N-labeled sulfate modifying the soil in order to identify the sources of N2O and the pathways of nitrification and denitrification. Three soil moisture contents (50% WHC, 75% WHC, and 100% WHC) along with three levels of anaerobically digested swine manure (0 g·kg−1, 10 g·kg−1, and 25 g·kg−1) were tested using randomized block design. Although the combined effect of contents of anaerobically digested swine manure and the soil moisture contents added to the system stimulated the utilization of soil N and promoted denitrification, the process of nitrification dominated. In anaerobically digested swine manure-treated soils, the rate of contribution of anaerobically digested swine manure to N2O accounted for 68.6–99.8%. In the 25 g·kg−1 treatment, the maximum of N2O produced by denitrification and nitrification were 14.1% and 93.1%. [ABSTRACT FROM AUTHOR]

Three ester-containing gemini surfactants (CmDEGs) were used to construct UV-responsive micellar systems with sodium trans-ortho-methoxycinnamate (trans-NaOMCA) as photo-sensitive additive. The effect of tail-chain length and spacer chain length on the UV-responsive ability was preliminarily explored. Longer tail chain and shorter spacer chain are favorable factors for enhancing UV-responsive ability. The addition of trans-NaOMCA into N,N′-bis(2-(dodecanoyloxy)ethyl)-N,N,N′,N′-tetramethyl-1,3-propane diammonium dibromide (C12DEG3) aqueous solution leads to a peak in zero-shear viscosity (η0) versus composition curve, and its further addition induces aqueous two-phase separation. For the C12DEG3/trans-NaOMCA/H2O mixed micellar systems, the UV responsiveness of significant decrease in η0 ascribes to microstructural transitions arising from the changes in counterion binding modes due to the trans-cis photoisomerization of NaOMCA. In comparison with the gemini surfactant 12-3-12, C12DEG3 has ester groups introduced in its tail chains. The introduction of ester groups leads to a significant effect on enhancing the photo-responsive ability in viscosity decrease of the constructed UV-responsive micellar systems. Furthermore, the effect of the addition of an amino acid–based surfactant sodium lauroylglutamate (SLGlu) into the C12DEG3/trans-NaOMCA/H2O mixed system on the UV-responsive behaviors was explored. In addition to UV-induced significant decrease in η0 and phase transition from aqueous two-phase systems (ATPS) to isotropic single-phase systems, the addition of SLGlu can also cause UV-induced increase in η0 and lead to richer UV-induced phase transition behaviors. The reason leading to these differences due to the presence of SLGlu was discussed based on 1H NMR spectra, molecular dynamics (MD) simulation, and molecular electrostatic potential (MEP) analysis. [ABSTRACT FROM AUTHOR]

We study the fragmentation function of the gluon to color-octet 3S1 heavy quark-antiquark pair using the soft gluon factorization (SGF) approach, which expresses the fragmentation function in a form of perturbative short-distance hard part convoluted with one-dimensional color-octet 3S1 soft gluon distribution (SGD). The short distance hard part is calculated to the next-to-leading order in αs and all orders in velocity expansion. By deriving and solving the renormalization group equation of the SGD, threshold logarithms are resummed to all orders in perturbation theory. The comparison with gluon fragmentation function calculated in NRQCD factorization approach indicates that the SGF formula resums a series of velocity corrections in NRQCD which are important for phenomenological study. [ABSTRACT FROM AUTHOR]

Background: Currently, insufficient bone volume always occurs in the posterior maxilla which makes implantation difficult. Short implants combined with transcrestal sinus floor elevation (TSFE) may be an option to address insufficient bone volume. Purpose: The clinical performance of short implants combined with TSFE was compared with that of conventional implants combined with TSFE according to the survival rate. Method: In this systematic review and meta-analysis, we followed the Meta-Analysis of Observational Studies in Epidemiology (MOOSE) guidelines. Articles were identified through PubMed, Embase, the Cochrane Library, and manual searching. Eligibility criteria included clinical human studies. The quality assessment was performed according to the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines. The odds ratio (OR) with its confidence interval (CI) was considered the essential outcome for estimating the effect of short implants combined with TSFE. Results: The registration number is INPLASY202050092. Eleven studies met the inclusion criteria, including 1 cohort study and 10 cross-sectional studies. With respect to the 1-year survival rate, no significant effect was observed between short implants (length ≤ 8 mm) and conventional implants combined with TSFE (I2=0%, OR=1.04, 95% CI: 0.55-1.96). Similarly, no difference was seen between the two groups regarding the survival rate during the healing period (I2=10%, OR=0.74, 95% CI: 0.28-1.97) and 3-year loading (OR=1.76, 95% CI: 0.65-4.74). Conclusion: There was no evidence that the survival rate of short implants combined with TSFE was lower or higher than that of conventional implants combined with TSFE when the residual bone height was poor and the implant protrusion length of short implants was less than or similar to conventional implants. Nevertheless, the results should be interpreted cautiously due to the lack of random controlled trials in our meta-analysis. [ABSTRACT FROM AUTHOR]

In this study, the dynamic response of buried fluid-conveying pipelines subjected to blast loading using the Love shell theory has been investigated. The fluid is considered as ideal fluid, and the velocity potential is used to describe the fluid pressure acting on the pipeline. The governing equations of the buried fluid-conveying pipelines are derived through Hamilton's principle. The modal superposition method and the Newmark integral method are used to analyze the dynamic response of the pipelines under blast loading. Results show that the displacement amplitudes of the pipelines are larger in the soil with a higher acoustic impedance. The Winkler foundation can enhance the stiffness of the pipelines. Moreover, the increase in the scaled distance leads to the decrease in the displacement amplitudes of the pipelines. The increase in the fluid velocity results in the rise of the displacement amplitudes of the pipelines. In addition, the maximum displacement increases first and then decreases with the increase in length-to-radius ratio of the pipelines. With the increase in thickness-to-radius ratio, the maximum displacement of the pipelines tends to decrease. [ABSTRACT FROM AUTHOR]

In the present study, we analyze the nonlinear forced vibration of thin-walled metal foam cylindrical shells reinforced with functionally graded graphene platelets. Attention is focused on the 1:1:1:2 internal resonances, which is detected to exist in this novel nanocomposite structure. Three kinds of porosity distribution and different kinds of graphene platelet distribution are considered. The equations of motion and the compatibility equation are deduced according to the Donnell's nonlinear shell theory. The stress function is introduced, and then, the four-degree-of-freedom nonlinear ordinary differential equations (ODEs) are obtained via the Galerkin method. The numerical analysis of nonlinear forced vibration responses is presented by using the pseudo-arclength continuation technique. The present results are validated by comparison with those in existing literature for special cases. Results demonstrate that the amplitude–frequency relations of the system are very complex due to the 1:1:1:2 internal resonances. Porosity distribution and graphene platelet (GPL) distribution influence obviously the nonlinear behavior of the shells. We also found that the inclusion of graphene platelets in the shells weakens the nonlinear coupling effect. Moreover, the effects of the porosity coefficient and GPL weight fraction on the nonlinear dynamical response are strongly related to the porosity distribution as well as graphene platelet distribution. [ABSTRACT FROM AUTHOR]

Inconel 718 alloys were fabricated by selective laser melting under different scanning speeds to investigate the change of the morphology of molten pool, direction of grain growth, and tensile properties. Results show that as the scanning speed increases from 1,000 to 1,450 mm·s−1, the ratio between depth and width of molten pool increases, yet their overlapping regimes decrease. Meanwhile, increasing scanning speed can promote the solidified structure evolve from cell to columnar dendrites, and decrease the dendrite spacing from 0.54 to 0.39 µm; the average columnar grain size also decreases from 84.42 to 73.51 µm. At different scanning speeds, the preferred orientation of grains along the building is mainly <001> direction. In addition, the tensile properties of samples under different scanning speeds present a non-monotonic transition. The maximum ultimate tensile strength and elongation can reach 1,014±19 MPa and 19.04±1.12 (%), respectively, at the scanning speed of 1,300 mm·s−1. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the efficacy of fronto-orbit reconstruction surgery on pediatric metopic synostosis via an image-based 3D reconstruction in Chinese population. Methods: Thirty pediatric metopic synostosis patients who received fronto-orbital reconstruction surgery in the Children's Hospital of Nanjing Medical University, Department of Neurosurgery, from January 2007 to December 2018 were analyzed in the study. Here we use the Mimics 20.0 software to reconstruct patients' cranial thin-section CT scan images from pre- and post-operation and control groups. Then the data of intracranial volume, frontal volume, orbital hypertelorism, ECA, ZF, and ORA were analyzed using the paired t-test or Wilcoxon matched-pairs signed-ranks test. Results: The age of these patients was 15.83 ± 16.12 months. After surgery, the mean frontal volume was enlarged from 92.75 ± 26.97 to 138.62 ± 47.97 cm3 (P < 0.0001), and the intracranial volume was enhanced from 976.87 ± 230.83 to 1059.44 ± 217.98 cm3 (P < 0.0001). In the meantime, the ECA was changed from 108.02 ± 8.17 to 134 ± 5.59° (P < 0.0001). In line with the alteration of the parameters mentioned above, the head shapes in all patients were also significantly improved after the surgery with no obvious complications. Conclusion: Fronto-orbit reconstruction surgery is a safe and effective treatment for pediatric metopic synostosis. Computer-aided 3D reconstruction could serve as a quantitative strategy to evaluate the efficacy of craniofacial surgery. [ABSTRACT FROM AUTHOR]

Advances in additive manufacturing have been mostly driven by developments in software and hardware for 3D printing. However, the limited number of printable polymers still restricts the applications of this technique. Researchers have made progress in the development of advanced polymeric materials that are compatible with 3D printing, by using a wide array of chemical interactions. In this prospective article, we discuss how 3D-printing technology can benefit from a supramolecular toolbox of dynamic covalent and non-covalent bonds. Furthermore, we aim to highlight how this toolbox is helping to overcome the main challenges in processability, functionality, and sustainability for 3D printing. [ABSTRACT FROM AUTHOR]

Polymer memristors with light weight and mechanical flexibility are preeminent candidates for low-power edge computing paradigms. However, the structural inhomogeneity of most polymers usually leads to random resistive switching characteristics, which lowers the production yield and reliability of nanoscale devices. In this contribution, we report that by adopting the two-dimensional conjugation strategy, a record high 90% production yield of polymer memristors has been achieved with miniaturization and low power potentials. By constructing coplanar macromolecules with 2D conjugated thiophene derivatives to enhance the π–π stacking and crystallinity of the thin film, homogeneous switching takes place across the entire polymer layer, with fast responses in 32 ns, D2D variation down to 3.16% ~ 8.29%, production yield approaching 90%, and scalability into 100 nm scale with tiny power consumption of ~ 10−15 J/bit. The polymer memristor array is capable of acting as both the arithmetic-logic element and multiply-accumulate accelerator for neuromorphic computing tasks. Though polymer memristors are promising for low‐power flexible edge computing applications, realizing efficient nanometer‐scale arrays remains a challenge. Here, the authors report a record high 90% production yield in nm‐scale 2D conjugated polymer memristors with homogeneous resistive switching. [ABSTRACT FROM AUTHOR]

We investigated the effect of CYP2C19 polymorphisms on the clinical outcomes of clopidogrel therapy in patients after stenting procedure for cerebral artery stenosis in northeast China. 568 patients performed CYP2C19 genotype screening in the neurosurgery department of our hospital; 154 patients were finally recruited according to the inclusion and exclusion criteria, and followed-up for 6 months. Ischemic events including (1) transient ischemic attack (TIA); (2) stent thrombosis; (3) ischemic stroke; and (4) death were defined as primary clinical endpoints. The frequencies of CYP2C19*1, *2 and *3 alleles in 568 patients were 63.1%, 31.1% and 5.8%, respectively. 154 patients were classified into extensive (65 patients; 42.2%), intermediate (66 patients; 42.9%), and poor (23 patients; 14.9%) metabolizer groups. A χ2 test showed a significant difference in primary clinical endpoints at 6 months (P = 0.04), and a multivariate Cox regression analysis indicated that the CYP2C19 loss-of-function (LOF) alleles associated with post-procedure prognosis. The Kaplan–Meier curve revealed that there was no significant difference in ischemic events between *2 and *3 alleles carriers. Our study verifies that CYP2C19 *2 and *3 have significant impact on the clinical outcomes of clopidogrel therapy in patients with stenting procedure for cerebral artery stenosis in China. [ABSTRACT FROM AUTHOR]

In this study, we aimed to investigate the role of SH2 domain-containing protein tyrosine phosphatase-2 (SHP-2) in cardiac remodeling after myocardial infarction (MI) and explore the underlying molecular mechanism. MI model was established by ligation of the left anterior descending coronary artery. C57/BL6J mice were randomly administered with 3.0 mg/kg/day PHPS1 (PHPS1-treated group) or normal saline (model group) by intraperitoneal injection. After 4 weeks of infusion, the effects of PHPS1 on cardiac remodeling were evaluated. Echocardiography results showed that PHPS1 treatment aggravated the MI-induced deterioration of cardiac function, with worse cardiac function parameters. PHPS1 treatment significantly increased the infarcted area, as well as the fibrotic area and the expression of collagen I and collagen III. Western blots and immunofluorescence staining showed that PHPS1 treatment up-regulated the expression of p-GRK2, p-SMAD2/3 and p-ERK1/2, while U0126 reversed the effect of PHPS1. The present study indicated that PHPS1 treatment contributed to myocardial fibrosis and infarction by activating ERK/SMAD signaling pathway, suggesting that SHP-2 may be a promising treatment target for cardiac remodeling after MI. [ABSTRACT FROM AUTHOR]

Transformer is the most important equipment in the power system. The research and development of fault diagnosis technology for Internet of Things equipment can effectively detect the operation status of equipment and eliminate hidden faults in time, which is conducive to reducing the incidence of accidents and improving people's life safety index. Objective: To explore the utility of Internet of Things in power transformer fault diagnosis system. Methods: A total of 30 groups of transformer fault samples were selected, and 10 groups were randomly selected for network training, and the rest samples were used for testing. The matter-element extension mathematical model of power transformer fault diagnosis was established, and the correlation function was improved according to the characteristics of three ratio method. Each group of power transformer was diagnosed for four months continuously, and the monitoring data and diagnosis were recorded and analyzed result. GPRS communication network is used to complete the communication between data acquisition terminal and monitoring terminal. According to the parameters of the database, the working state of the equipment is set, and various sensors are controlled by the instrument driver module to complete the diagnosis of transformer fault system. Results: The detection success rate of the power transformer fault diagnosis system model established in this paper is as high as 95.6%, the training error is less than 0.0001, and it can correctly identify the fault types of the non training samples. It can be seen that the technical support of the Internet of Things is helpful to the upgrading and maintenance of the power transformer fault diagnosis system. [ABSTRACT FROM AUTHOR]

Delayed emergence from anesthesia was previously reported in a case study of a child with Glycine Encephalopathy. To investigate the neural basis of this delayed emergence, we developed a zebrafish glial glycine transporter (glyt1 − / −) mutant model. We compared locomotor behaviors; dose–response curves for tricaine, ketamine, and 2,6-diisopropylphenol (propofol); time to emergence from these anesthetics; and time to emergence from propofol after craniotomy in glyt1−/− mutants and their siblings. To identify differentially active brain regions in glyt1−/− mutants, we used pERK immunohistochemistry as a proxy for brain-wide neuronal activity. We show that glyt1−/− mutants initiated normal bouts of movement less frequently indicating lethargy-like behaviors. Despite similar anesthesia dose–response curves, glyt1−/− mutants took over twice as long as their siblings to emerge from ketamine or propofol, mimicking findings from the human case study. Reducing glycine levels rescued timely emergence in glyt1−/− mutants, pointing to a causal role for elevated glycine. Brain-wide pERK staining showed elevated activity in hypnotic brain regions in glyt1−/− mutants under baseline conditions and a delay in sensorimotor integration during emergence from anesthesia. Our study links elevated activity in preoptic brain regions and reduced sensorimotor integration to lethargy-like behaviors and delayed emergence from propofol in glyt1−/− mutants. [ABSTRACT FROM AUTHOR]

Place attachment has been a research focus in the fields of park and recreation management. Place attachment plays an important role in promoting sustainable development of parks and mountain tourism destination, however, there are limited studies that identified the spatial patterns of place attachment, especially in the context of mountain tourism destinations in China. Also, the geospatial spectrum of visitors is usually broad, examining the multivariate relationships among spatial proximity, perceived authenticity, and place attachment are essential for mountain tourism destinations to promote destination image and strengthen emotional bonding with targeted visitor groups. In this study, we selected an iconic and highly visited park, Jiuzhai Valley National Park in China, as our study site and conducted an on-site visitor survey to collect 557 samples. Study uses factor analysis and the structure equation model to analyze the relationship among spatial proximity, perceived authenticity, and place attachment. Results validate the two-dimension structure of place attachment and perceived authenticity. Study findings suggest that spatial proximity has significant impacts on existential authenticity and place identity, but has no significant impacts on place dependence. Perceived authenticity has a positive impact on place attachment. Study results advance the theories of place attachment and provide effective strategies to enhance emotional attachment between visitors and mountain tourism destinations. [ABSTRACT FROM AUTHOR]

Trigeminal neuralgia is a debilitating condition, and the pain easily spreads to other parts of the face. Here, we established a mouse model of partial transection of the infraorbital nerve (pT-ION) and found that the Connexin 36 (Cx36) inhibitor mefloquine caused greater alleviation of pT-ION-induced cold allodynia compared to the reduction of mechanical allodynia. Mefloquine reversed the pT-ION-induced upregulation of Cx36, glutamate receptor ionotropic kainate 2 (GluK2), transient receptor potential ankyrin 1 (TRPA1), and phosphorylated extracellular signal regulated kinase (p-ERK) in the trigeminal ganglion. Cold allodynia but not mechanical allodynia induced by pT-ION or by virus-mediated overexpression of Cx36 in the trigeminal ganglion was reversed by the GluK2 antagonist NS102, and knocking down Cx36 expression in Nav1.8-expressing nociceptors by injecting virus into the orofacial skin area of Nav1.8-Cre mice attenuated cold allodynia but not mechanical allodynia. In conclusion, we show that Cx36 contributes greatly to the development of orofacial pain hypersensitivity through GluK2, TRPA1, and p-ERK signaling. [ABSTRACT FROM AUTHOR]

The chemical composition variation of the TiAl-4722 alloys was examined in a batch of the industrial scale master ingots, and in the corresponding castings prepared by conventional vacuum arc remelting (VAR) combined with induction skull melting (ISM) and investment casting processes. The content changes of major elements and interstitial elements were evaluated based on the chemical analysis at the top and bottom of the ingots and castings. Results show that the contents of C, N, H, Fe and Si have almost no change in the ingots and castings, suggesting that the chemical analysis on these elements can be based on the batch analysis. The O content keeps almost the same in different ingots, but exhibits relatively large differences in castings, which was probably influenced by the reaction between the shell mold and the molten alloy, and the spalling of face coat of the shell mold during casting. For the major elements of Al, Nb and Cr, the composition difference between the top and the bottom of the ingots is less than that of the castings. But for the O element, the trend is different, especially for the castings, suggesting that the investment casting is a homogenization process for Cr and Nb, but a differentiation process for O. The contents of major elements in castings fluctuate mainly in the same range as that in the ingots, indicating that the contents of the major elements are controllable during investment casting. [ABSTRACT FROM AUTHOR]

Intermetallic Ti-45Al-8Nb-(W, B, Y) (at.%) and Ti-46Al-5Nb alloys are directionally solidified at a constant growth rate of 30 µm·s-1 using a Bridgman type apparatus. The quenched microstructures and lengths of different phase regions were observed and measured after various growing times of 0-30 min. Results show that the phase transformations in different phase regions are mainly depending on the high temperature microstructure and the supercooling degree during quenching process. After isothermal holding, the primary phase grows into the liquid phase, the dendrites change from equiaxed to columnar grains, and the length of the L+ß phase region, L+ß+a phase region and mushy zone varies, indicating that the entire directional solidification process can be described by a static equilibrium - nonequilibrium - dynamic equilibrium evolution process. In addition, the gap between the original growth interface and front interface shows that the actual crystal growth rate is not equal to the drawing velocity during directional solidification. [ABSTRACT FROM AUTHOR]

To improve the microstructure and microhardness, Ti-48Al (at.%) alloy was rapidly solidified by melt spinning under different cooling rates. The microstructure and microhardness of rapidly solidified Ti-48Al alloy were systematically investigated. Results show that the average lamellar colony size of the alloy reduces from 60.6 µm to 11 µm as the cooling rate increases from 2.3×105 to 5.1×105 K·s-1, caused by the increase of nucleation rate at a higher cooling rate. At the high cooling rate of (4.3- 5.1)×105 K·s-1, the a phase is the primary phase, and a few metastable a phases are reserved, which then transform into a2 phase and subsequently lead to the formation of a2 equiaxed grain. The lamellar spacing also decreases with the increase of cooling rate. The relationship between lamellar spacing (d) and cooling rate (v) is d=33.6v -1.34. The microhardness increases with the increase of cooling rate because the refined lamellar spacing and grain size can improve the microhardness. [ABSTRACT FROM AUTHOR]

Interleukin (IL)-35, which has an anti-inflammatory role in acute respiratory distress syndrome (ARDS)/acute lung injury (ALI), is relatively promising as a drug target. Studies have shown that curcumin may play a therapeutic role in ALI and enhance the suppressive function of regulatory T cells (Tregs). To illustrate the effect of curcumin on the regulation of Treg cell differentiation and expression of IL-35, we built a cecal ligation and puncture (CLP)–induced acute lung injury mouse mode with curcumin pretreatment. The expression of IL-35 in serum, severity of lung injury, IL-17A in lung tissue, survival rate, Treg-related cytokines levels in serum, nuclear factor-kappa B (NF-κB)'s nuclear translocation in lung tissue, and splenic CD4+CD25+FOXP3+ Tregs were assessed. Furthermore, the proportion of Tregs, STAT5, and IL-35 expression during naïve CD4+ T cell differentiation in vitro was measured. Compared with the CLP group, the increased IL-35 expression in CLP with the curcumin pretreatment (CLP + Cur) group was consistent with the decreased severity of lung injury, IL-17A protein levels in lung tissue, and Treg-related cytokines levels. Pretreatment with curcumin, the survival rate climbed to 50%, while the mortality rate was 100% in the CLP group. In addition, splenic CD4+CD25+FOXP3+ Treg cells increased in the CLP + Cur group. In vitro, CD4+CD25+FOXP3+ Treg cells from naïve CD4+ T cells, STAT5 proportion, and IL-35 expression increased after curcumin treatment. These findings showed that curcumin might regulate IL-35 by activating the differentiation of Treg cells to control the inflammation in acute lung injury. [ABSTRACT FROM AUTHOR]

Background and Objective: Without a specific antiviral treatment or vaccine, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global pandemic, affecting over 200 countries worldwide. A better understanding of B- and T-cell immunity is critical to the diagnosis, treatment and prevention of coronavirus disease 2019 (COVID-19). Methods: A cohort of 129 patients with COVID-19 and 20 suspected cases were enrolled in this study, and a lateral flow immunochromatographic assay (LFIA) and a magnetic chemiluminescence enzyme immunoassay (MCLIA) were evaluated for SARS-CoV-2 IgM/IgG detection. Additionally, 127 patients with COVID-19 were selected for the detection of IgM and IgG antibodies to SARS-CoV-2 to evaluate B-cell immunity, and peripheral blood lymphocyte subsets were quantified in 95 patients with COVID-19 to evaluate T-cell immunity. Results: The sensitivity and specificity of LFIA-IgM/IgG and MCLIA-IgM/IgG assays for detecting SARS-CoV infection were > 90%, comparable with reverse transcription polymerase chain reaction detection. IgM antibody levels peaked on day 13 and began to fall on day 21, while IgG antibody levels peaked on day 17 and were maintained until tracking ended. Lymphocyte and subset enumeration suggested that lymphocytopenia occurred in patients with COVID-19. Conclusions: LFIA-IgM/IgG and MCLIA-IgM/IgG assays can indicate SARS-CoV-2 infection, which elicits an antibody response. Lymphocytopenia occurs in patients with COVID-19, which possibly weakens the T-cell response. [ABSTRACT FROM AUTHOR]

A series of novel quinolinyl imidazolidin-2-imine nickel complexes with different substituents on the imidazolidin-2-imine ligand were synthesized and characterized. The complexes in the presence of methylaluminoxane (MAO) as a cocatalyst catalyzed the copolymerization of norbornene (N) and styrene (S) or para-chlorostyrene (CS) with high activity (up to 1070 kg·mol−1·h−1). The installation of sterically bulky substituents on the imidazolidine-2-imine ligand was effective for the increase of the molecular weight and the comonomer content, affording high molecular weight copolymers with tunable CS content (0.57 mol%–11.7 mol%), in which the existence of Cl group can provide reaction site for the further functionalization of copolymers as well as the synthesis of graft or cross-linked polymers. The linear relationship between the comonomer content and the glass transition temperature of the copolymers and the monomer reactivity ratios in the copolymerization indicated the formation of the expected functionalized cyclic olefin copolymers (COC). [ABSTRACT FROM AUTHOR]

Two new coumarins, 6-hydroxymethyl-3-prenyl-7-methoxycoumarin (1) and 6-hydroxyethyl-3-prenyl-7- methoxycoumarin (2), together with three known coumarins (3–5), were isolated from the roots and stems of Yunyan-300, a variety of Nicotiana tabacum L. Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. Compounds 1 and 2 were tested for their anti-methicillinresistant Staphylococcus aureus (anti-MRSA) activity and their antioxidant activity. The results revealed that compounds 1 and 2 showed good anti-MRSA inhibitions with IZD of 12.2 ± 1.8 and 11.8 ± 1.5 mm, respectively, and antioxidant activity with an IC50 value of 4.65 and 4.85 μg/mL, respectively. [ABSTRACT FROM AUTHOR]

(*, IBS-D FSN vs. control FSN in BDNF+/- mice; #, IBS-D FSN in BDNF+/+ mice vs. in BDNF+/- mice; †control FSN in BDNF+/+ mice vs. in BDNF+/- mice). (B) TrkB/Fc significantly suppressed the effect of IBS-D FSN at 30, 45 and 60 mmHg (*, IBS-D FSN vs. control; #, IBS-D FSN vs. [Extracted from the article]

Many patients of choroidal neovascularization (CNV) are unresponsive to the current anti-VEGF treatment. The mechanisms for anti-VEGF resistance are poorly understood. We explore the unique property of the apolipoprotein A-I (apoA-I) binding protein (AIBP) that enhances cholesterol efflux from endothelial cells and macrophages to thereby limit angiogenesis and inflammation to tackle anti-VEGF resistance in CNV. We show that laser-induced CNV in mice with increased age showed increased resistance to anti-VEGF treatment, which correlates with increased lipid accumulation in macrophages. The combination of AIBP/apoA-I and anti-VEGF treatment overcomes anti-VEGF resistance and effectively suppresses CNV. Furthermore, macrophage depletion in old mice restores CNV sensitivity to anti-VEGF treatment and blunts the synergistic effect of combination therapy. These results suggest that cholesterol-laden macrophages play a critical role in inducing anti-VEGF resistance in CNV. Combination therapy by neutralizing VEGF and enhancing cholesterol removal from macrophages is a promising strategy to combat anti-VEGF resistance in CNV. By combining advanced age and laser photocoagulation, Zhu et al. establish a novel CNV model of anti-VEGF resistance. They show that lipid accumulation in old macrophages promote angiogenesis, and that apoA-I binding protein (AIBP) inhibits angiogenesis by reducing this lipid accumulation. They further show that the combination of AIBP/apoA-I and anti-VEGF treatment overcomes anti-VEGF resistance and effectively suppresses CNV. [ABSTRACT FROM AUTHOR]

Dear Sir, In early December 2019, a severe acute respiratory infection was firstly reported in Wuhan and then recognized as coronavirus disease 2019 (COVID-19). In response to the WHO statements and international concerns regarding the COVID-19 outbreak, the Chinese Society of Nuclear Medicine (CSNM) promptly put forward a consensus on the management of nuclear medical care (NM care) during the COVID-19 epidemic [[7]]. Retrospective NM findings of COVID-19 In retrospective studies, Qin et al. [[13]] and Zou et al. [[14]] have reported the SP 18 sp F-FDG PET/CT findings in COVID-19 patients. [Extracted from the article]

The effect of growth rates (V=2-50 µm·s-1) on microstructure and microhardness of directionally solidified Ti-44Al-5Nb-1.5Cr-1.5Zr-1Mo-0.1B (at.%) alloy at a constant temperature gradient (G=18 K·mm-1) was investigated. Results indicated that ß phase was the primary phase of the directionally solidified Ti-44Al- 5Nb-1.5Cr-1.5Zr-1Mo-0.1B alloy. As the growth rate increases, the solid/liquid interface turns from cellular growth to dendric growth. The interlamellar spacing (Δs) decreases with the increase of growth rate according to the relationship of Δs=3.39V -0.31. The solidification segregation occurs due to the enrichment of ß-stabilizing element Nb, Cr in primary ß phase during solidification; moreover, the degree of the segregation increases with the growth rate, resulting in the emergence of B2 phase in lamellar colonies at high growth rates. The microhardness (Hv) grows with the growth rate based on the equation of HV=328.69V 0.072, which mainly attributes to the microstructure refinement. [ABSTRACT FROM AUTHOR]

The power generation and thermal stress of a segmented thermoelectric generator (TEG) under a pulsed heat source are analyzed in this paper. The distribution of thermal stress in four-part thermoelectric materials and its development over time are discussed. The influence of duty cycle on the maximum thermal stress is analyzed. The effects of welding layer thickness on thermal stress and output energy are also discussed. The results show that reducing the duty cycle can increase the amount of power generated, accompanied by an increase in thermal stress. Increasing the thickness of the welding layer can effectively reduce the thermal stress in the bismuth telluride layer. Detailed analysis of thermal stress in thermoelectric materials under pulsed heat sources with different duty cycles can provide guidance for the structural design and reliability analysis in the practical application of a TEG. [ABSTRACT FROM AUTHOR]

It is very significant to improve the diameter accuracy of micro-shafts fabricated by micro-electrical discharge machining (micro-EDM) in micro-tools application. The diameter accuracy includes the uniformity of a single micro-shaft in axial direction and the repeatability of micro-shafts with the same diameter. A newly proposed method, named twin-mirroring-wire tangential feed electrical discharge grinding (TMTF-WEDG), can realize high uniformity and repeatability of micro-shafts via tangentially feeding and constraining of a narrow slit formed by a twin-mirroring-wire on the diameter of micro-shafts, respectively. Controlling the material removal thickness in single-step machining of micro-shafts is necessary to achieve high uniformity and repeatability. This paper focuses on the effects of the several important factors on the material removal thickness of micro-shafts to reveal the effects on the diameter uniformity and repeatability, including the open voltage, capacitance, feed rate in the Z-direction, feed step in the Y-direction, and tangential feed distance. The results indicate that the lower open voltage or the smaller capacitance or higher Z-direction feed rate, the smaller the thickness of the material removed, which is advantageous for controlling the consistency and repeatability of the micro-shafts. Decreasing of Y-direction feed step from 20 to 5 μm is accompanied by a reduction in material removal thickness, and the material removal thickness of less than 0.4 μm is achieved with a smaller feed step of in the Y-direction. As the tangential feed distance S2 decreases, the material removal thickness of the micro-shafts decreases gradually. In this study, the uniformity and repeatability of brass and tungsten micro-shafts are controlled within 1 μm and 2 μm, respectively. [ABSTRACT FROM AUTHOR]

A bulk Poly(vinyl alcohol)/ZIF-8 (PVA/ZIF-8) porous composite with aligned porous structure was prepared by ice-templating method. The microstructure of PVA/ZIF-8 porous composites was characterized by scanning electron microscopy (SEM). The results showed that the composites had regular pore structure and ZIF-8 nanoparticles were evenly distributed on the skeleton of PVA. X-ray diffraction (XRD) test results showed that the crystalline structure of ZIF-8 was well preserved in the composites. The specific surface area of the composite was characterized by nitrogen adsorption/desorption test. The specific surface area of the composite was up to 1160 m2·gt1. PVA/ZIF-8 porous composites could also support a certain weight with almost no volume shrinkage. The carbon dioxide adsorption quantity of the composite was up to 11.3 cm3·gt1, proving that PVA/ZIF-8 porous composite has a good application prospect in the field of carbon dioxide adsorption. [ABSTRACT FROM AUTHOR]

Mitochondrial dysfunction is a hallmark of Alzheimer's disease (AD), which may be related to mitophagy failure. Previous reports suggest that treadmill exercise protects against mitochondrial dysfunction in AD. However, few studies have investigated the relationship between mitophagy and mitochondrial adaptation caused by treadmill exercise in AD. The current study aimed to investigate whether exercise-ameliorated AD is associated with changes in mitophagy activity. Both Wild-type and APP/PS1 transgenic mice were divided into sedentary (WTC and ADC) and exercise (WTE and ADE) groups (n = 9 for each group). WTE and ADE mice were subjected to treadmill exercise for 12 weeks, followed by evaluating the effect of treadmill exercise on learning and memory ability, Aβ plaques, mitochondrial Aβ peptide level, synaptic activity and mitochondrial function. Meanwhile, mitophagy-related proteins PINK1, Parkin, LC3II and P62 were measured in the hippocampal mitochondrial fractions. The results indicated that exercise not only restored learning and memory ability, but also reduced Aβ plaque area, mitochondrial Aβ peptide level, and increased levels of synaptic markers SYN and GAP43, as well as reversed mitochondrial dysfunction (defective mitochondrial ultrastructure, decreased PGC-1α, TFAM and ATP levels) in APP/PS1 transgenic mice. Moreover, exercise increased mitophagy activity as evidenced by a significant decrease in levels of P62 and PINK1 as well as an increase in levels of LC3II and Parkin in ADE mice. These findings suggest that treadmill exercise can enhance mitophagy activity in the hippocampus, which is efficient in ameliorating pathological phenotypes of APP/PS1 transgenic mice. [ABSTRACT FROM AUTHOR]

In this paper, we study the application of the recently proposed soft gluon factorization (SGF) to exclusive quarkonium production or decay. We find that in the nonrelativistic QCD factorization framework there are too many nonperturbative parameters. Thanks to the factorization of kinematical physics from dynamical physics, the SGF significantly reduces the number of nonperturbative parameters. Therefore, the SGF can improve our predictive power of exclusive quarkonium production or decay. By applying to ηc + γ production at B-factories, our result is the closest one to data among all theoretical calculations. [ABSTRACT FROM AUTHOR]

Microstructural improvement of Al-Cu-Li alloys with high Li content plays a critical role for the acquisition of excellent mechanical properties and ultra-low density. In this regard, the Al-Cu-Li alloy castings with high Li content from 1.5wt.% to 4.5wt.% were prepared by near-rapid solidification, followed by two-stage homogenization treatment (490 °C/16 h and 530 °C/16 h). The microstructural evolution and solidification behavior of the as-cast and homogenized alloys with different Li contents were systematically studied by combining experiments with calculations by Pandat software. The results indicate that with the increase of Li content, the grain sizes decrease, the solution ability of Cu in the matrix a-Al phase increases, while the content of secondary dendrites increases and the precipitated phases change from low melting point phases to high melting point phases under the near-rapid solidification. Additionally, by the coupling of near-rapid solidification and two-stage homogenization, the metastable precipitated phases (Al7Cu4Li and AlCu3) can be dissolved effectively in the alloys with Li content of 1.5wt.%-2.5wt.%; moreover, the stable precipitated phases (Al6CuLi3 and Al2CuLi) uniformly distribute at the grain boundaries in the alloys with Li content of 3.5wt.%-4.5wt.%. As a result, the refined and homogenized microstructure can be obtained. [ABSTRACT FROM AUTHOR]

Different fertilization regimes can substantially influence soil fungal community composition, yet fewer studies try to control for the effects of nitrogen input. Here, we investigated the impact of fertilization with equal nitrogen upon soil properties and soil fungal diversity and community composition in the North China Plain in a long-term field experiment. Long-term (32 years) fertilization regimes were applied with equal amounts of nitrogen: no chemical fertilizer or organic manure; chemical fertilization only; organic manure fertilization only, and; combination of 1/2 chemical fertilizer and 1/2 organic manure. Then we investigated the influence of these four fertilization regimes to soil properties, fungal diversity and community composition. The results showed that applying organic manure significantly influenced soil properties. Illumina MiSeq sequencing and its analysis revealed that organic manure fertilization significantly changed soil fungal alpha diversity, but chemical fertilization did not. Although soil fungal community composition did not differ significantly among all the fertilization regimes at the phylum and class levels, they did show differences in the abundance of dominant fungi. Yet at the genus level, soil fungal community composition, abundance, and beta diversity was affected by all fertilization regimes. Application of organic manure also reduced the abundance of soil-born fungal pathogens such as Fusarium. Our results suggest that long-term application of organic manure could markedly improve soil properties, altering soil fungal community composition and its diversity. Moreover, organic manure fertilization could limit soil-born fungal diseases, to further contribute to soil ecosystem sustainability. [ABSTRACT FROM AUTHOR]

Embryo implantation is an essential and complex process in mammalian reproduction. However, little evidence has indicated the involvement of autophagy during embryo implantation. To determine the possible role of autophagy in uterine of pregnant mice during the peri-implantation stage, we first examined the expression of autophagy-related markers ATG5 and LC3 on day 4, 5, and 6 of pregnancy (D4, D5, and D6, respectively). Compared with expression on D4, downregulation of the autophagy-related markers was observed on D5 and D6, the days after the embryo attached to the receptivity endometrium. Further examination showed that autophagy-related markers ATG5, ATG12, LC3, cathepsin B, and P62 at the implantation site were significantly decreased when comparing with the inter-implantation site. Fewer number of autophagosomes at the implantation site were also observed by transmission electron microscopy. To confirm the functional role of autophagy during embryo implantation in mice, we administered the autophagy inhibitor 3-methyladenine and chloroquine to mice. After treated with 3-methyladenine, the expression of decidual markers HOXA10 and progesterone receptor were significantly reduced. Furthermore, a reduction in implantation sites and increase in the HOXA10 and PR protein levels were observed in response to chloroquine treatment. In addition, impaired uterine decidualization and dysregulation of the PR and HOXA10 protein levels was observed after autophagy inhibited by 3-methyladenine and chloroquine in in vivo artificial decidualization mouse model. In the last, LC3 and P62 were also observed in normal human proliferative, secretory, and decidua tissues. In conclusion, endometrial autophagy may be essential for embryo implantation, and it may be associated with endometrial decidualization during early pregnancy. Key message: • Autophagy-related markers were significantly decreased at implantation site. • Autophagy inhibition results in abnormal decidualization. • Autophagy is essential for embryo implantation. [ABSTRACT FROM AUTHOR]

Two new anti-tobacco mosaic virus (anti-TMV) xanthones, 4,7-dimethoxy-5-hydroxymethyl-1-methylxanthone (1) and 7-hydroxy-5-hydroxymethyl-4-methoxy-1-methylxanthone (2), were isolated from the whole plants of Comastoma pedunculatum. Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. Compounds 1 and 2 showed high anti-TMV activity with inhibition rates of 48.5 and 63.6%, respectively. These rates are higher than that of positive control. [ABSTRACT FROM AUTHOR]

The article provides a design of all-optical non-gate and NOR gate based on two-dimensional photonic crystal ring resonator structure. This design extracts the energy band structure of two-dimensional photonic crystals by plane wave expansion method and analyzes the steady-state electric field distribution of the device structure by the fi-nite-time-domain difference method. The results demonstrate that the non-gate and NOR gate can achieve logic functions with a response period of 0.388 ps, a contrast ratio of 8.98 dB and 7.88 dB. The high extinction ratio and small structure sizes which are only 15.2 μm×15.2 μm and 13.984 μm×24.928 μm also contribute to convenient integration. The design with ring resonator makes optical logic gate devices more diverse, providing a basis for the optimal design of integrated circuits, and it also has important application research value. [ABSTRACT FROM AUTHOR]

By the use of the gauge/gravity duality, we calculate the imaginary part of heavy quarkonium potential and thermal width with the effect of gluon condensate which is absent in AdS 5 background. Our results show that the dropping gluon condensate reduces the absolute value of imaginary potential and therefore decreases the thermal width both in "exact" and "approximate" approach implying that the heavy quarkonium has a weaker bound with the increase of gluon condensate. In addition, the thermal width will disappear at a critical condensate value, which indicates the dissociation of quarkonium. We conclude that increasing gluon condensate will lead to easier dissociation of heavy quarkonium for fixed temperature. [ABSTRACT FROM AUTHOR]

Background: Although robotic surgery is popular around the world, its safety and efficacy over classical open surgery is still controversial. The purpose of this article is to compare the safety and efficacy of robotic pancreaticoduodenectomy (RPD) and open pancreaticoduodenectomy (OPD).Methods: A literature search of PubMed, Web of Science, and the Cochrane Library database up to July 29, 2018 was performed and the meta-analysis was performed using RevMan 5.2 software with Fixed and random effects models applied. The IRB approval and written consent were not needed for this paper.Results: Twelve non-randomized retrospective studies and 1 non-randomized prospective study consisting of 2403 patients were included in this meta-analysis. There were 788 (33%) patients in the RPD group and 1615 (67%) patients in the OPD group. Although RPD was associated with a longer operative time (weighted mean difference [WMD]: 71.74 min; 95% CI 23.37-120.12; p = 0.004), patient might benefit from less blood loss (WMD: - 374.03 ml; 95% CI - 506.84 to - 241.21; p < 0.00001), shorter length of stay (WMD: - 5.19 day; 95% CI - 8.42 to - 1.97; p = 0.002), and lower wound infection rate (odds ratio: 0.17; 95% CI 0.04-0.80; p = 0.02). No statistically significant difference was observed in positive margin rate, lymph nodes harvested, postoperative complications, reoperation or readmission rate, and mortality rate.Conclusions: Robotic pancreaticoduodenectomy is a safe and feasible alternative to open pancreaticoduodenectomy with regard to short-term outcomes. Further studies on the long-term outcomes of these surgical techniques are needed. [ABSTRACT FROM AUTHOR]