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Cold hole expansion is a crucial technology for enhancing the fatigue life of hole structures. This paper presents the design and optimization of a novel multi-convex hulls expansion tool for deep small holes in Inconel 718 superalloy using the finite element method (FEM) and experimental techniques. The results from the FEM model, which was used to investigate the compressive residual stress (CRS) distribution and contact force during the expansion process, indicate that the curved single convex hull (CSCH) structure is more suitable for deep small hole expansion (DSHE). However, accounting for the strength limitations of the actual expansion tool, a multi-convex hulls expansion tool structure was proposed. The FEM model was employed to compare the effects of various tool structures on the hole wall CRS distribution and the contact force during the expansion process. The obtained optimal parameters for enhancing deep small holes in Inconel 718 superalloy under high temperature and high load conditions are as follows: expansion section hull spacing l1 = 0.4 mm, taper ratio C = 0.008, number of convex hulls in the sizing section n = 10, and sizing section hull spacing l2 = 1 mm. Moreover, an optimized convex hull expansion amount allocation scheme was obtained through an experimental study. The results of the FEM simulations and experimental study demonstrate that the optimized multi-convex hulls expansion tool (with an expansion rate of 1.92%) can induce the formation of a high CRS layer and a refined surface without causing significant microcracks in the hole walls. [ABSTRACT FROM AUTHOR]

The ribosomally synthesized and post-translationally modified peptide (RiPPs) class of natural products has undergone significant expansion due to the rapid growth in genome sequencing data. Using a bioinformatics approach, we identify the dehydrazoles, a novel class of hypermodified RiPPs that contain both side chain dehydration of Ser residues, and backbone heterocyclization at Ser, Thr, and Cys residues to the corresponding azol(in)es. Structure elucidation of the hypermodified peptide carnazolamide, a representative class member, shows that 18 post-translational modifications are installed by just five enzymes. Complete biosynthetic reconstitution demonstrates that dehydration is carried out by an unusual DUF4135 dehydration domain fused to a zinc-independent cyclase domain (CcaM). We demonstrate that CcaM only modifies Ser residues that precede an azole in the core peptide. As heterocyclization removes the carbonyl following the Ser residue, CcaM likely catalyzes dehydration without generating an enolate intermediate. Additionally, CcaM does not require the leader peptide, and this core-dependence effectively sets the order for the biosynthetic reactions. Biophysical studies demonstrate direct binding of azoles to CcaM consistent with this azole moiety-dependent dehydration. Bioinformatic analysis reveals more than 50 related biosynthetic gene clusters that contain additional catalysts that may produce structurally diverse scaffolds. Ribosomally synthesized and post-translationally modified peptides (RiPPs) are natural products with significant chemical complexity. Here, the authors identify the dehydrazoles, a class of hypermodified RiPPs with side chain dehydration and backbone heterocyclization, and identify enzymes involved in their biosynthesis and modifications. [ABSTRACT FROM AUTHOR]

Extracellular vesicles (EVs) have tremendous potential as nano/micron-sized drug delivery carriers. Their physical, chemical and biological characteristics distinguish them as unique carriers with specific pharmacokinetic, circulating metabolic, and biodistribution patterns in the delivery of therapeutic cargoes. They are critical mediators in the pathology of many diseases, including inflammatory diseases, fibrosis, and cancer, but they are also essential mediators in immunomodulation, cancer treatment, infectious defense, and tissue repair. In this review, we emphasize recent advances in oncology therapy using macrophage EVs, mesenchymal stem cell EVs, milk EVs, and plant EVs, as well as the advantages of EVs as delivery platforms and their prospective clinical applications and use. [ABSTRACT FROM AUTHOR]

A novel refractive index (RI) sensor based on a D-shaped single-mode-graded-index multimode-single-mode fiber (D-SGIMS) structure is presented and investigated in detail. A CO2 laser was used to process the SGIMS structure, which produced a strong evanescent field. The structural parameters were determined via simulations, and the experimental results were consistent with those of the theoretical analysis. The transmission spectra and RI sensitivity of the fabricated sensors with different lengths were compared via experiments, the results of which indicated that the maximum RI sensitivity was 811.00 nm/RIU in the range 1.333–1.419. Therefore, the proposed D-SGIMS structure can provide high-precision measurement capabilities and can be applied in the field of biochemistry. [ABSTRACT FROM AUTHOR]

All memristor neuromorphic networks have great potential and advantage in both technology and computational protocols for artificial intelligence. It is crucial to find suitable elementary units for both performing featured neuromorphic functions and fabrication in large scale. Here a simple memristive structure, Nb/HfOx/Pd, is proposed for this goal. Its two resistive switching mechanisms, Mott transition of NbO2 and oxygen vacancy (Vo) migration, can be controlled by modulating external bias directions. Negative bias activates reversible phase transition and restrains Vo filament formation to allow the memristor to mimic the firing action potential. Positive bias activates Vo filament formation and restrains the other to allow the memristor to mimic synaptic plasticity and learning protocols. The system can respond adaptively to naturally generated action potentials and modified synaptic signals from the same memristive structure. In addition, some special features related to signal encoding and recognition are discovered when the system is settled according to chaos circuit theory. Our study provides a novel approach for designing elementary units for neuromorphic computations. [ABSTRACT FROM AUTHOR]

With the popularization of electric vehicles (EVs), more and more charging stations are deployed in the urban area. This brings practical interest to the operation optimization of the charging station in a competitive charging market. As EV drivers are sensitive to the charging cost, the charging price is one of the major concerns during the operation optimization for the charging station. This paper considers this important problem and makes the following contributions. Firstly, a charging demand simulation method is proposed to generate the potential charging demand based on the transportation network and EV trip characteristic. By multiple scenarios generation, the uncertainties in the charging demand can be incorporated. Secondly, a competitor awareness model is proposed to predict the possible charging pricing policies of the competitors. This method can discover the implicit relationship between pricing policy and the status of the competitors without the requirement of the competitors’ utility functions. Thirdly, a Grey wolf optimization (GWO)-based charging price determination algorithm is proposed considering the uncertain charging demand, the pricing policies of the competitors and the charging willingness of EVs. Numerical results demonstrate that the proposed method can improve the competitiveness and the operation profit of the charging station. [ABSTRACT FROM AUTHOR]

Background: In orthodontics, mechanical stress plays an important role in the process of bone remodeling. Mechanical stress has an effect on osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs). However, the mechanism remains to be studied. The aim of this study is to investigate the effects of demethyltransferase fat mass and obesity-associated (FTO) on osteogenic differentiation of BMSCs under mechanical stress condition. Methods and results: The rat BMSCs were cultured in vitro, followed by flow cytometry to identify the cell surface antigens. Osteogenic differentiation of BMSCs was induced by mechanical stress by using the flexcell tension system for 6 h every day and 3 days in total. BMSCs were transfected by using plasmid for FTO knockdown. The expression level of FTO, hypoxia-inducible factor (HIF)-1α, runt-related transcription factor 2 (RUNX2), bone morphogenetic proteins (BMPs) and alkaline phosphatase (ALP) were measured by real-time qPCR, western blotting. ALP activity were determined by ALP staining assays. The expression of FTO and HIF-1α in BMSCs with mechanical stress were significantly higher than BMSCs without mechanical stress, also, the expression of osteogenic differentiation markers were higher in BMSCs with mechanical stress. Knockdown of FTO decreased expression of osteogenic differentiation marker and ALP activity in stretched BMSCs. In addition, the expression of HIF-1α was decreased after knocking down FTO. Conclusions: FTO promotes the expression of HIF-1α and osteogenic differentiation under the condition of mechanical stress. This finding may facilitate the clinical application of orthodontics and the mechanism research of mechanical stress-induced osteogenesis. [ABSTRACT FROM AUTHOR]

Temperate phages are potential therapeutic agents, but only a few temperate phages infecting multidrug-resistant Acinetobacter baumannii have been identified. In this study, we isolated 5W, a temperate phage that infects multidrug-resistant A. baumannii, from pond water using the enrichment method. A member of the Siphoviridae family, 5W has a narrow host range and infected only four of 19 A. baumannii clinical isolates. It exhibited rapid adsorption (> 90% in 6 min), a latency period of 20 min, and a burst size of ~ 180 plaque-forming units (PFU/cell). 5W contains a linear double-stranded DNA (dsDNA) genome of 43,032 bp with a GC content of 39.85%. The 5W genome contains 61 open reading frames, including lysogen-forming genes, but lacks any known virulence and antibiotic resistance genes. The lysin of 5W is an N-acetyl-β-d-muramidase belonging to the GH_108 family. The α-helical structure and highly positively charged amino acids in the C-terminal region indicate potential antibacterial activity against A. baumannii, and the M/S subunits of the restriction endonuclease are inserted into the lysogenic gene cluster. Comparative genome analysis revealed high similarity with two different prophages in A. baumannii ABCR01, suggesting that 5W may be derived from recombination of other prophages. [ABSTRACT FROM AUTHOR]

Purpose: To analyse the relationship between multiple anatomic characteristics of the knee (tibia and femur) and isolated meniscal injury in women and men. Methods: Forty-seven patients with isolated medial meniscal injuries, 62 patients with isolated lateral meniscal injuries, and 70 control subjects were included. Medial posterior tibial slope (MTS), lateral posterior tibial slope (LTS), medial tibial plateau depth (MTD), coronal tibial slope (CTS), femoral notch width (NW), femoral condylar width (FCW), intercondylar notch depth (ND), femoral notch width index (NWI), intercondylar notch shape index (NSI), and cruciate ligaments tensity (CLT) were measured from magnetic resonance images. Anatomic characteristics differing between groups were compared, and risk factors for isolated meniscal injury were identified by multivariate forward stepwise logistic regression for men and women separately. Results: Risk factors for an isolated medial meniscal injury were a steeper MTS and a lowered MTD in men, and a steeper MTS and an increased NWI in women. Risk factors for isolated lateral meniscal injury were a steeper LTS and an increased NW in men, and a steeper LTS and a lowered ND in women. Risk factors for both medial and lateral meniscal injuries were a higher CTS, an increased NWI, and a looser CLT in men, and a higher CTS, an increased NSI, and a looser CLT in women. Conclusion: The anatomic characteristics of the tibial plateau, femur, and cruciate ligaments influence the risk of suffering isolated meniscal injury, and the risk factors differ between men and women. This study provides a reference for developing identification criteria for those at risk of isolated meniscal injury. Level of evidence: III. [ABSTRACT FROM AUTHOR]

The effective control of the tip-leakage flow and loss is of great significance to improve the aerodynamic performance of the turbine. In this paper, the evolution mechanism of tip-leakage flow in a transonic high pressure turbine with a squealer tip is investigated with numerical simulation methods. The impacts of squealer geometric, such as the inclined pressure side rim and squealer rim width, on the vortex structure in the gap and tip-leakage loss are discussed. The results show that the scraping vortex inside the cavity plays the role of aero-labyrinth seal, and forms interlocking sealing labyrinth structure with the rims on both sides, which has an effective sealing effect on the tip-leakage flow. The inclined pressure side squealer rim inhibits the development of the pressure side squealer corner vortex, which is beneficial to expand the influence range of the scraping vortex and enhance the sealing effect on the tip-leakage flow. The increase of the suction side squealer rim width reduces the effective flow area at the gap exit, which is conducive to reduction of the tip-leakage flow rate and tip-leakage loss. However, the increase of the pressure side squealer rim width strengthens the pressure side squealer corner vortex and limits the development space of the scraping vortex, causing the adverse effects on the control of tip-leakage flow. [ABSTRACT FROM AUTHOR]

With the continuous development of society, people have entered a new era. People's material needs have been basically met, and people are paying more and more attention to spiritual life and ecological health. After the problem of food and clothing was solved, people began to pursue leisure sports, which is a brand new direction of consumption. The coastal area has taken the lead in developing the exciting experience of leisure sports. The leisure environment in this area is very romantic and can also bring people a very exciting experience. In recent years, many people have gone to the coastal area to experience this kind of leisure sports, which has also promoted tourism. The economic development of the city in the coastal area has promoted the change of its development mode. We monitor rainfall in coastal areas, which plays an important role in the development of leisure sports. If we can predict the weather changes in advance, we can make timely countermeasures, make reasonable plans for sports time, and make reasonable arrangements for sports content. In this paper, the relationship between cloud cover changes and rainfall data is obtained by monitoring remote sensing cloud images, and a corresponding model is established. This paper also designs some cloud image parameters, uses the corresponding algorithm to explore the relationship between cloud image and rainfall, improves and optimizes the algorithm combined with matrix characteristics, and finally proposes a more efficient algorithm. After a series of experiments, it is proved that the algorithm proposed in this paper has higher timeliness and better accuracy. The research results of this project have been applied to the forecast of rainfall trends in coastal areas. At the same time, certain suggestions and strategies have been put forward for the development of leisure sports activities in coastal areas, which also laid the foundation for the development of subsequent leisure activities. [ABSTRACT FROM AUTHOR]

The present study investigated the effects of forced overexpression of Phox2a/2b, two transcription factors, in the locus coeruleus (LC) of aged rats on noradrenergic and dopaminergic phenotypes in brains. Results showed that a significant increase in Phox2a/2b mRNA levels in the LC region was paralleled by marked enhancement in expression of DBH and TH per se. Furthermore, similar increases in TH protein levels were observed in the substantial nigra and striatum, as well as in the hippocampus and frontal cortex. Overexpression of Phox2 genes also significantly increased BrdU-positive cells in the hippocampal dentate gyrus and NE levels in the striatum. Moreover, this manipulation significantly improved the cognition behavior. The in vitro experiments revealed that norepinephrine treatments may increase the transcription of TH gene through the epigenetic action on the TH promoter. The results indicate that Phox2 genes may play an important role in improving the function of the noradrenergic and dopaminergic neurons in aged animals, and regulation of Phox2 gene expression may have therapeutic utility in aging or disorders involving degeneration of noradrenergic neurons. [ABSTRACT FROM AUTHOR]

The structure and morphology of Al interdigital transducers as a function of Ni underlayer thickness were studied. The Al (111) texture intensity increases first and then decreases as Ni underlayer thickness increases. 6-nm Ni underlayer results in the strongest Al (111) texture with flattest surface, which exhibits almost 10 times longer life in electromigration measurement than those without Ni underlayer. 1.5 GHz surface acoustic wave filters fabricated with Al film on 6-nm Ni underlayer also have improved power durability compared with those without Ni underlayer from 29.0 to 32.5 dBm. It is observed that those fine grains in the 6-nm Ni underlayer greatly enhance Al (111) texture. Together with increased adhesion force, strong Al (111) texture accounts for the improved resistance to electromigration and acoustomigration via the reduction of gains boundaries, resistivity, and fine grains at the interface, which is promising for high power surface acoustic wave filters. [ABSTRACT FROM AUTHOR]

High-quality a-plane AlN epitaxial films were successfully deposited on r-plane sapphire using a thin ZnO buffer layer for surface acoustic wave (SAW) applications. Structural properties of AlN epitaxial films on different thicknesses of ZnO buffer and the related SAW characteristics were investigated systematically. The results demonstrate that AlN films were epitaxially grown on ZnO buffered-substrate with orientation relationship of (112¯0)[101¯0] AlN//(112¯0)[101¯0] ZnO//(011¯2)[2¯110] Al2O3. A thin ZnO buffer layer with moderate thickness significantly facilitated the crystal quality of a-plane AlN films, and in turn enhanced the SAW characteristics. High frequency SAW devices with a center frequency of ~ 1500 MHz corresponding to a high phase velocity of 6000 m/s were achieved on the obtained AlN films. The as-grown a-plane AlN epitaxial films with 40 nm optimized ZnO buffer exhibit high crystal quality with a FWHM value of the rocking curve of 0.76° and good performance of SAW devices with low insertion loss and large out-of-band rejection. This work offers an effective approach to achieve high-quality a-plane AlN epitaxial films on sapphire substrates for the AlN-based SAW devices applications. [ABSTRACT FROM AUTHOR]

High quality ZnO/SiC composite structure have great potential in integrating surface acoustic wave devices with semiconductor devices. To achieve high quality ZnO on 6H-SiC, ZnO films were sputtered with various power by radio frequency magnetron sputtering. It was observed that all films possessed hexagonal wurtzite crystal structure with c-axis orientation. With the increasing of sputtering power, the growth rate rose steadily while the in-plane orientation of ZnO thin films gradually degraded. The FWHM of rocking curve, stress, intensity of visible emission reached a maximum at 125 W and then decreased with sputtering power further increasing. Films deposited at 75 W exhibited narrowest rocking curve of 1.44°, lowest visible emission and stress with orientation relationship: $${(0002)_{{\text{ZnO}}}}\parallel {(0006)_{{\text{SiC}}}}$$ and $${[11\bar {2}0]_{{\text{ZnO}}}}\parallel {[11\bar {2}0]_{{\text{SiC}}}}$$ . TEM and XPS results show that the interlayer is responsible for the degraded in-plane orientation, while the various point defects in non-equilibrium sputtering results in those visible emission. Those results demonstrate that increasing sputtering power greatly deteriorate quality of ZnO on 6H-SiC by interlayer and amount of point defects, while exorbitant sputtering power can recover these properties by increasing adatom mobility to some degree. [ABSTRACT FROM AUTHOR]

DNA polymerase-β (DNA pol-β) plays a crucial role in the pathogenesis of Parkinson's disease (PD). The aim of this study was to investigate the neuroprotective effects of a DNA polymerase-β inhibitor 2′,3′-dideoxycytidine (DDC) in PD models. In the in vitro studies, primary cultured neurons were challenged with 1-methyl-4-phenylpyridinium ion (MPP). The expression of DNA pol-β was assessed using western blot. The neuroprotective effect of DNA pol-β knockdown and DNA pol-β inhibitor DDC was determined using cell viability assay and caspase-3 activity assay. We found that MPP induced neuronal death and the activation of caspase-3 in a dose-dependent manner. The expression of DNA pol-β increased after the neurons were exposed to MPP. DNA pol-β siRNA or DNA pol-β inhibitor DDC attenuated neuronal death induced by MPP. In the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mouse model of PD, MPTP treatment triggered behavioral deficits and nigrostriatal lesions. Pretreatment with DDC attenuated MPTP-induced behavioral deficits, dopaminergic neuronal death and striatal dopamine depletion in the MPTP mouse model. These results indicate that DNA pol-β inhibitors may present a novel promising therapeutic option for the neuroprotective treatment of PD. [ABSTRACT FROM AUTHOR]

Pulse responses were studied for the heterojunctions within the structure of Ti/poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS)/Ti. The pulse response was found to resemble that of the action potential after the pulse width was modulated to a time scale of nanoseconds. Using the pulse as a stimulation protocol to simulate synaptic plasticity produced spike rate-dependent plasticity-like phenomena. Thus, the application scope of this conducting polymer-based memristor can be extended from a time scale of milliseconds to one of nanoseconds, depending on the requirement of neuromorphic circuits. Current oscillations were observed with a period within 100 ns. The mechanisms of the behavior response were analyzed according to memristor protocol. An interface barrier is thought to primarily account for the origin of the capacitive feature and the charge q, i.e., one of the basic characteristic of the memristor. The chain structure of this conducting polymer should primarily account for the origin of its inductive feature and the flux φ, i.e., another basic characteristic of the memristor. [ABSTRACT FROM AUTHOR]

High performance piezoelectric ceramics with high Curie temperatures ( T ) are the bottle necks of relevant high temperature devices. In this study, the electrical performance and microstructure of Li and Mn codoped Aurivillius-type composite ceramics with a composition CaBi(LiMn)NbTiO ( x = 0-0.8) were systematically investigated. The results indicated that uniform intergrowth structure with a lattice similar to that of the end member CBT could be formed at a low x value ( x < 0.4). Phase separation occurred when more A-site Ca ions were replaced by Bi ions. Nevertheless, all composite samples showed d values about 2 to 3 times of that of the constituent phase CaBiTiO and BiTiNbO with still a high depolarization temperature. The performance of the samples was found to be related to the density and larger lattice distortion along the polarization a axis. The results also demonstrated that formation of the compound system was an effective way in improving the performance of Aurivillius-type high T piezoelectric ceramics. [ABSTRACT FROM AUTHOR]

Highly c-axis oriented aluminum nitride (AlN) films, which can be used in flexible surface acoustic wave (SAW) devices, were successfully deposited on polyimide (PI) substrates by direct current reactive magnetron sputtering without heating. The sputtering power, film thickness, and deposition pressure were optimized. The characterization studies show that at the optimized conditions, the deposited AlN films are composed of columnar grains, which penetrate through the entire film thickness (~2 μm) and exhibit an excellent (0002) texture with a full width at half maximum value of the rocking curve equal to 2.96°. The film surface is smooth with a root mean square value of roughness of 3.79 nm. SAW prototype devices with a center frequency of about 520 MHz and a phase velocity of Rayleigh wave of about 4160 m/s were successfully fabricated using the AlN/PI composite structure. The obtained results demonstrate that the highly c-axis oriented AlN films with a smooth surface and low stress can be produced on relatively rough, flexible substrates, and this composite structure can be possibly used in flexible SAW devices. [ABSTRACT FROM AUTHOR]

PEGylated and folate-targeted chitosan polymeric nanoparticles (FPNs) for the treatment of gastric carcinoma were prepared successfully. OQC-anchored folate conjugates were synthesized and used in assembling FPNs nano-system for enhancing intracellular uptake against folate receptor overexpressing cancer cells. The results indicated that folate-targeted chitosan polymeric nanoparticles (CPNs) can reverse drug-resistant SGC-7901 cells of 5-fluorouracil (5-FU) compared with non-targeted CPNs. Increased therapeutic efficiency of 5-FU/METHFR shRNA co-loaded PNs were also tested in SGC-7901 cells and compaed with 5-FU or METHFR shRNA in solution, which was associated with increased cell inhibition function for single drug group and synergistic effects of 5-FU and METHFR shRNA at 2.0 µg/mL FPNs concentration. In addition, the cell accumulation levels of 5-FU in SGC-7901 cells was time dependent for these nanoparticles. FPNs (effective diameter: 83.2 ± 1.1 nm; polydispersity index: 0.193) could significantly boost cellular accumulation of 5-FU and overcome the drug efflux mechanism of MDR than 5-FU-loaded NPNs and 5-FU in solution. In conclusion, ligand-targeted PNs can be used as a potentially effective drug delivery system. [ABSTRACT FROM AUTHOR]

Enhancing ion conductance and controlling transport pathway in organic electrolyte could be used to modulate ionic kinetics to handle signals. In a Pt/Poly(3-hexylthiophene-2,5-diyl)/Polyethylene+LiCFSO/Pt hetero-junction, the electrolyte layer handled at high temperature showed nano-fiber microstructures accompanied with greatly improved salt solubility. Ions with high mobility were confined in the nano-fibrous channels leading to the semiconducting polymer layer, which is favorable for modulating dynamic doping at the semiconducting polymer/electrolyte interface by pulse frequency. Such a device realized synaptic-like frequency selectivity, i.e., depression at low frequency stimulation but potentiation at high-frequency stimulation. [ABSTRACT FROM AUTHOR]

Anthracene-based cylindrical macrotricyclic polyether (1) containing two dibenzo-30-crown-10 cavities has been proved to be an efficient host for the templated complexation with N,N′-dipropyl-1,4,5,8-naphthalenetetracarboxylic diimide in the presence of lithium ions in both solution and solid state. Host 1 could also form 1:1 complex with the bispyridinium salt with two β-hydroxyethyl groups in solution and in the solid state. Moreover, it was also found that the switchable complexation processes between the macrotricyclic host and two different kinds of guests could be chemically controlled by the addition and removal of lithium ions. [ABSTRACT FROM AUTHOR]

In recent years, with the growing concerns on environmental protection and human health, new materials, such as lead-free piezoelectric materials, have received increasing attention. So far, three types of lead-free piezoelectric systems have been widely researched, i.e., perovskites, bismuth layer-structured ferroelectrics, and tungsten-bronze type ferroelectrics. This article presents a new type of environmental friendly piezoelectric material with simple structure, the transition-metal(TM)-doped ZnO. Through substituting Zn site with small size ion, we obtained a series of TM-doped ZnO with giant piezoresponse, such as ZnVO of 170 pC/N, ZnCrO of 120 pC/N, ZnMnO of 86 pC/N and ZnFeO of 127 pC/N. The tremendous piezoresponses are ascribed to the introduction of switchable spontaneous polarization and high permittivity in TM-doped ZnO. The microscopic origin of giant piezoresponse is also discussed. Substitution of TM ion with small ionic size for Zn results in the easier rotation of noncollinear TM-O1 bonds along the c axis under the applied field, which produces large piezoelectric displacement and corresponding piezoresponse enhancement. Furthermore, it proposes a general rule to guide the design of new wurtzite semiconductors with enhanced piezoresponses. That is, TM-dopant with ionic size smaller than Zn substitutes for Zn site will increase the piezoresponse of ZnO significantly. Finally, we discuss the improved performances of some TM-doped ZnO based piezoelectric devices. [ABSTRACT FROM AUTHOR]

Purpose: The association between polymorphism of vascular endothelial growth factor (VEGF)-634 G>C and malignancy risk has been widely studied, and no conclusive result was available up to now. Methods: Twenty-three case-control studies with 21,917 individuals were included in this meta-analysis through searching the databases of Medline, Embase, and CNKI (up to October 1st, 2010). The odds ratio (OR) and 95% confidence interval (95%CI) were used to investigate the strength of the association. Results: Overall, the pooled analysis showed that there was no association between VEGF-634 G>C and risk of malignancy, and the ORs (95%CIs) were 0.98 (0.85-1.12) for GG versus CC, 1.03 (0.90-1.17) for GC versus CC, 1.00 (0.89-1.13) for G carrier versus CC, and 1.08 (0.94-1.23) for C carrier versus GG. Subgroup analyses according to ethnicity, source of control, type of cancer, and sample size were also performed, and results indicated that VEGF-634 G>C was not associated with risk of malignancy for neither Asians [1.06 (0.81-1.38) for GG vs. CC and 1.08 (0.84-1.39) for GC vs. CC] nor Caucasians [0.93 (0.83-1.05) for GG vs. CC and 0.98 (0.87-1.10) for GC vs. CC]. It was also not associated with risk of breast cancer [0.95 (0.81-1.12) for GG vs. CC], gastric cancer [0.93 (0.47-1.84) for GG vs. CC], and colorectal cancer [1.17 (0.93-1.47) for GG vs. CC]. Conclusions: This meta-analysis suggests that VEGF-634 G>C may be not associated with risk of malignancy. More studies with larger sample size were needed to provide more precise evidence. [ABSTRACT FROM AUTHOR]

Experimental confirmation of various grain scattering theories exist but there are still outstanding questions concerning the characterization of microstructure using ultrasound. In this study, high purity niobium serves as a model material devoid of extrinsic scattering centers (e.g., voids, precipitates, second phase particles etc.) A range of microstructures were obtained by annealing in ultrahigh vacuum at different temperatures (600–800°C) after routine cold-rolling and recrystallization heat treatment. Ultrasonic attenuation is measured as a function of a frequency for each sample. For the samples with an intermediate grain size (typically ∼50 μm), attenuation follows a power law dependence on frequency with an exponent of n∼1.6, which is close to the prediction, n=2, of classical Stochastic scattering theory. However, quantitative comparison shows that the observed attenuation is higher than predicted by the classical theory. The Stanke-Kino unified grain scattering theory may provide an explanation for the lower frequency dependence than traditional theories predict, though it still under predicts the magnitude of the attenuation. In any event, the resulting empirical relations provide a useful approach for practical grain size measurement with an acceptable level of uncertainty. The effect of a layered microstructure typical of some sheets/plates is discussed. [ABSTRACT FROM AUTHOR]

Endometriosis (EMS) is a common gynecological condition with apparent heterogeneity, lack of diagnostic markers, and unclear pathogenesis. A series of bioinformatics methods were employed to explore EMS’s pathological mechanisms and potential biomarkers by analyzing the combined datasets of EMS (GSE7305, GSE7307, GSE58198, E-MTAB-694), which included 34 normal, 127 eutopic, and 46 ectopic endometrium samples. Then, wet-laboratory experiments (including Western blot, qRT-PCR, and Immunohistochemistry, Immunofluorescence, CCK-8, EdU, Wound healing, Transwell, and Adhesion assays) were applied to examine the biomarkers’ expression and function in primary endometrial stromal cells. Bioinformatic analysis indicated that the core pathogenesis of EMS was dysregulated immune-inflammation and tissue remolding processes. Among the upregulated DEGs, BST2 was screened as a potential diagnostic biomarker in EMS, which associated with the revised American Fertility Society (r-AFS) stage and immune-inflammation processes of EMS. Moreover, BST2’s overexpression was affirmed in the RNA and protein levels in EMS tissues. In vitro experiments demonstrated that TNF-α promoted the expression of BST2 in ESCs. And BST2 knockdown inhibited migration, invasion, adhesion, and inflammation except for the proliferation of ESCs, probably via the TNF-α/NF-κB pathway. Through a combination of wet and dry studies, we concluded that the core pathogenesis of endometriosis was dysregulated immune-inflammation and tissue remolding, and BST2 might be a potential diagnostic and therapeutic target in endometriosis. [ABSTRACT FROM AUTHOR]