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Space-based gravitational wave detection is extremely sensitive to disturbances. The Keplerian configuration cannot accurately reflect the variations in spacecraft configuration. Planetary gravitational disturbances are one of the main sources. Numerical simulation is an effective method to investigate the impact of perturbation on spacecraft orbits. This study shows that, in the context of the Taiji project, Earth's gravity is an essential factor in the change in heliocentric formation configuration, contributing to the relative acceleration between spacecrafts in the order of O (10 − 6) m · s − 2 . Considering 00:00:00 on 27 October 2032 as the initial orbiting moment, under the influence of Earth's gravitational perturbation, the maximum relative change in armlengths and variation rates of armlengths for Taiji is 1.6 × 10 5 km , 32 m · s − 1 , respectively, compared with the unperturbed Keplerian orbit. Additionally, by considering the gravitational perturbations of Venus and Jupiter, the armlength and relative velocity for Taiji are reduced by 16.01 % and 17.45 % , respectively, compared with when only considering that of Earth. The maximum amplitude of the formation motion indicator changes with the orbit entry time. Results show that the relative velocity increase between the spacecrafts is minimal when the initial orbital moment occurs in July. Moreover, the numerical simulation results are inconsistent when using different ephemerides. The differences between ephemerides DE440 and DE430 are smaller than those between DE440 and DE421. [ABSTRACT FROM AUTHOR]

The flavor-changing neutral current (FCNC) decays of charmed hadrons with missing energy (Ɇ) can serve as potentially promising hunting grounds for hints of new physics, as the standard-model backgrounds are very suppressed. A few of such processes have been searched for in recent experiments, specifically D0→ Ɇ by Belle and D0→ π0Ɇ and Λ c + → pɆ by BESIII, resulting in upper bounds on their branching fractions. We consider them to illuminate the possible contributions of the quark transition c → uɆ with a couple of invisible spinless bosons carrying away the missing energy, assuming that they are not charge conjugates of each other and hence can have unequal masses. We find that these data are complementary in that they constrain different sets of the underlying operators and do not cover the same ranges of the bosons' masses, but there are regions not yet accessible. From the allowed parameter space, we show that other D-meson decays, such as D → ρɆ, and the charmed-baryon ones Ξc → (Σ, Λ)Ɇ can have sizable branching fractions and therefore may offer further probes of the new-physics interactions. We point out the importance of D0 → γɆ which are not yet searched for but could access parts of the parameter space beyond the reach of the other modes. In addition, we look at a scenario where the invisibles are instead fermionic, namely sterile neutrinos, and a scalar leptoquark mediates c → uɆ. We discuss the implications of the aforesaid bounds for this model. The predictions we make for the various charmed-hadron decays in the different scenarios may be testable in the near future by BESIII and Belle II. [ABSTRACT FROM AUTHOR]

Lewis acid zeolites play an important role in industrially important green reactions closely related to fine chemical and biomass conversion. Titanium-doped TS-1 zeolite is a milestone Lewis acid zeolite widely used in industrially significant green oxidation processes with hydrogen peroxide as an oxidant under mild conditions. TS-1 zeolites are normally synthesized in basic conditions under hydrothermal treatment. Up to now, there has still been no success in synthesizing active TS-1 Lewis acid zeolites by using inorganic alkali, e.g., NaOH or KOH as base, which is cheaper and more stable compared to the quaternary ammonium hydroxide or organic amines used in traditional synthesis. Here, an inorganic base of NaOH was employed in synthesizing active TS-1 zeolites for the first time. The crucial factor was the control of adverse effects of sodium cations on the incorporation of active titanium cations. Higher catalytic activity was achieved by further reducing the size of the TS-1 crystal by using the seed-added strategy, which uses the catalytic activity of a commercial catalyst, the production cost being much lower than commercial TS-1 catalysts, indicating great commercial potential and the possibility of preparing other cheap Lewis acid catalysts by using inorganic alkali. [ABSTRACT FROM AUTHOR]

Titanium silicalite-1 (TS-1) is a milestone heterogeneous catalyst with single-atom tetrahedral titanium incorporated into silica framework for green oxidation reactions. Although TS-1 catalysts have been industrialized, the strategy of direct hydrothermal synthesis usually produces catalysts with low catalytic activities, which has still puzzled academic and industrial scientists. Post-treatment processes were widely chosen and were proven to be an essential process for the stable production of the high-activity zeolites with hollow structures. However, the reasons why post-treatment processes could improve catalytic activity are still not clear enough. Here, high-performance hollow TS-1 zeolites with nano-sized crystals and nano-sized cavities were synthesized via post-treatment of direct-synthesis nano-sized TS-1 zeolites. The influencing factors of the fabricating processes on their catalytic activities were investigated in detail, including the content of alkali metal ions, the state of titanium centers, hydrophilic/hydrophobic properties, and accessibility of micropores. The post-treatment processes could effectively solve these adverse effects to improve catalytic activity and to stabilize production. These findings contribute to the stable preparation of high-performance TS-1 catalysts in both factories and laboratories. [ABSTRACT FROM AUTHOR]

The price of spinel has sharply risen in recent years, and its market acceptance is extending. Among the many sources of spinel, Man Sin in Myanmar is the most famous for its bright neon pinkish red to reddish pink color, named "Jedi" spinel commercially. In this paper, spinel samples with the bright neon pinkish red to reddish pink from Man Sin in Myanmar were studied non-destructively with X-ray fluorescence spectrometer (EDXRF), Fourier transform infrared spectrometer (FTIR), fluorescence spectroscopy, a UV-Vis spectrophotometer and Raman spectroscopy. The results show that the samples from Man Sin in Myanmar are the magnesia-alumina spinels. The high content of the red-chromogenic element Cr, an intermediate content of V and Zn, and a low content of the chromogenic element Fe may be responsible for the distinctive neon color of the spinel samples. The presence of Ti may also serve as a basis for the identification of its origin in Man Sin in Myanmar. The fluorescence spectrum analysis of spinels shows them to have multiple excitation peaks in the region 600–800 nm, which are caused by the jump of Cr3+ between the 2E→4A2 inter-energy band lattice. The amount of Zn affects the fluorescence spectrum intensity of spinels. The higher the Zn content, the stronger the fluorescence intensity. The spinel structure is uncomplicated and four more obvious absorption peaks appear in the IR spectrum, and the direction of the absorption peaks is shifted if a homogeneous substitution of the AB2O4 structure occurs; the Raman spectra of spinel samples have four vibrational peaks at 100–2000 cm−1, 310 cm−1, 407 cm−1, 665 cm−1 and 763 cm−1, which has spinel species-identification significance. [ABSTRACT FROM AUTHOR]

Objective: Ischemia/reperfusion (IR)-induced myocardial arrhythmias are a common clinical manifestation in patients with myocardial infarction after reperfusion therapy. Mitochondria play a critical role in cardioprotection. Here, we investigated the effects of KH176 as a new mitochondrial-acting drug on IR-induced ventricular arrhythmias, mitochondrial function, pro-inflammatory cytokines production, and the role of mitochondrial ATP-dependent K (mK-ATP) channels in rats' hearts. Methods: The hearts of Sprague Dawley rats (250 ± 30 g; 36 rats) underwent 35 min of ischemia followed by 120 min of reperfusion. Myocardial in vivo ischemia was induced by ligation of the left anterior descending coronary artery. KH176 at concentrations of 10 and 50 μM was intraperitoneally injected to rats 10 min before reperfusion onset. Ventricular arrhythmias were quantified during reperfusion, and cardiac mitochondrial function, nitric oxide, and pro-inflammatory cytokines levels were measured by fluorometric, spectrophotometric, and ELISA techniques. Results: Administration of KH176 significantly reduced lactate-dehydrogenase release and the number, duration, incidence, and severity of ventricular arrhythmias induced by reperfusion injury. IR-induced elevation of mitochondrial reactive oxygen species production, and cardiac pro-inflammatory cytokines TNF-α, IL-6, and IL-1β, as well as reduction of mitochondrial membrane potential, ATP and nitric oxide levels were significantly restored by KH176 at 50 μM. However, the blockade of mK-ATP channels by 5-hydroxydecanoate considerably inhibited the effects of KH176 on all parameters except nitric oxide. Conclusion: KH176 showed strong cardiac antiarrhythmic effects on IR-induced injury through improving mitochondrial function and reducing inflammatory and oxidative responses, and these protective effects are mediated by cardiac mK-ATP channels. Graphical Abstract [ABSTRACT FROM AUTHOR]

This study characterizes the spatial patterns of the overall and monthly trends in sea surface temperature (SST) and chlorophyll-a (Chl-a) of the Gulf of Mexico (GoM) to investigate the seasonal variations in oceanic climate trends. We also investigate the trends in mesoscale eddies using three parameters to identify ocean-eddy-related energetic features in their area, strength, and intensity. Multidecadal remote-sensing-based observations of monthly SST, Chl-a, and sea surface height are used to detect trends at both basin and grid scales. Prominent warming trends are found in most regions of the GoM in all months, with the largest trends in the northern GoM. Winter cooling trends are also detected along the Texas and Florida coast. The overall summer warming trend (~0.22 °C/decade) is larger than the winter trend (~0.05 °C/decade), suggesting seasonal variations of increase in SST with warming. Chl-a trends and variations are confined on the continental shelf and slope in the northern GoM. The largest increase trends are found near the Mississippi River Delta. No obvious Chl-a trend is detected in the deepwater of the GoM, consistent with previous studies. Small but significant changes are found in eddy characteristics, indicating the eddy activities might be slowly affected by climate change in the GoM. The detailed monthly trends at per-grid scale are valuable for regional resource management, environmental protection, and policy making in the GoM. [ABSTRACT FROM AUTHOR]

The future sixth generation (6G) is going to face the significant challenges of massive connections and green communication. Recently, reconfigurable intelligent surfaces (RIS) and non-orthogonal multiple access (NOMA) have been proposed as two key technologies to solve the above problems. Motivated by this fact, we consider a downlink RIS-aided NOMA system, where the source aims to communicate with the two NOMA users via RIS. Considering future network supporting real-time service, we investigate the system performance with the view of effective capacity (EC), which is an important evaluation metric of delay sensitive systems. Specifically, we derive the analytical expressions of the EC of the near and far users. To obtain more useful insights, we deduce the analytical approximation expressions of the EC in the low signal-to-noise-ratio approximation by utilizing Taylor expansion. Moreover, we provide the results of orthogonal multiple access (OMA) for the purpose of comparison. It is found that (1) The number of RIS components and the transmission power of the source have important effects on the performance of the considered system; (2) Compared with OMA, NOMA system has higher EC due to the short transmission time. [ABSTRACT FROM AUTHOR]

C. Guo et al. (Hearing phenotypes of patients with hearing loss homozygous for the GJB2 c.235delc mutation) investigate the hearing phenotypes of 244 Chinese patients with hearing loss associated with the homozygous c.235delC mutation of GJB2 and report a significant variation in their binaural hearing loss phenotypes, including severity of hearing loss, and audiogram shapes. Although SNHL is induced by various factors through different approaches and mechanisms, the major cause for SNHL is irreversible loss of either inner ear hair cells (HCs) or degeneration of spiral ganglion neurons (SGNs). [Extracted from the article]

Protein lysine acetylation (Kac) is an important post-translational modification in both animal and plant cells. Global Kac identification has been performed at the proteomic level in various species. However, the study of Kac in oil and resource plant species is relatively limited. Soybean is a globally important oil crop and resouce plant. In the present study, lysine acetylome analysis was performed in soybean leaves with proteomics techniques. Various bioinformatics analyses were performed to illustrate the structure and function of these Kac sites and proteins. Totally, 3148 acetylation sites in 1538 proteins were detected. Motif analysis of these Kac modified peptides extracted 17 conserved motifs. These Kac modified protein showed a wide subcellular location and functional distribution. Chloroplast is the primary subcellular location and cellular component where Kac proteins were localized. Function and pathways analyses indicated a plenty of biological processes and metabolism pathways potentially be influenced by Kac modification. Ribosome activity and protein biosynthesis, carbohydrate and energy metabolism, photosynthesis and fatty acid metabolism may be regulated by Kac modification in soybean leaves. Our study suggests Kac plays an important role in soybean physiology and biology, which is an available resource and reference of Kac function and structure characterization in oil crop and resource plant, as well as in plant kingdom. [ABSTRACT FROM AUTHOR]

Dengue virus (DENV) is a mosquito-borne pathogen that causes a spectrum of diseases including life-threatening dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). Vascular leakage is a common clinical crisis in DHF/DSS patients and highly associated with increased endothelial permeability. The presence of vascular leakage causes hypotension, circulatory failure, and disseminated intravascular coagulation as the disease progresses of DHF/DSS patients, which can lead to the death of patients. However, the mechanisms by which DENV infection caused the vascular leakage are not fully understood. This study reveals a distinct mechanism by which DENV induces endothelial permeability and vascular leakage in human endothelial cells and mice tissues. We initially show that DENV2 promotes the matrix metalloproteinase-9 (MMP-9) expression and secretion in DHF patients' sera, peripheral blood mononuclear cells (PBMCs), and macrophages. This study further reveals that DENV non-structural protein 1 (NS1) induces MMP-9 expression through activating the nuclear factor κB (NF-κB) signaling pathway. Additionally, NS1 facilitates the MMP-9 enzymatic activity, which alters the adhesion and tight junction and vascular leakage in human endothelial cells and mouse tissues. Moreover, NS1 recruits MMP-9 to interact with β-catenin and Zona occludens protein-1/2 (ZO-1 and ZO-2) and to degrade the important adhesion and tight junction proteins, thereby inducing endothelial hyperpermeability and vascular leakage in human endothelial cells and mouse tissues. Thus, we reveal that DENV NS1 and MMP-9 cooperatively induce vascular leakage by impairing endothelial cell adhesion and tight junction, and suggest that MMP-9 may serve as a potential target for the treatment of hypovolemia in DSS/DHF patients. Author summary: DENV is the most common mosquito-transmitted viral pathogen in humans. In general, DENV-infected patients are asymptomatic or have flu-like symptoms with fever and rash. However, in severe cases of DENV infection, the diseases may progress to dengue hemorrhagic fever (DHF) or dengue shock syndrome (DSS), the leading causes of morbidity and mortality in school-age children in tropical and subtropical regions. DENV-induced vascular leakage is characterized by enhanced vascular permeability without morphological damage to the capillary endothelium. This study reveals a possible mechanism by which DENV NS1 and MMP-9 cooperatively induce vascular leakage. NS1 also recruits MMP-9 to degrade β-catenin, ZO-1, and ZO-2 that leads to intervene endothelial hyperpermeability in human endothelial cells and mouse vascular. Moreover, the authors further reveal that DENV activates NF-κB signaling pathway to induce MMP-9 expression in patients, mice, PBMC, and macrophages though NS1 protein. This study would provide new in signs into the pathogenesis of DENV infection, and suggest that MMP-9 may act as a drug target for the prevention and treatment of DENV-associated diseases. [ABSTRACT FROM AUTHOR]

Introduction. Hyperlipidemia is an underlying process behind cardiovascular disease. Chinese medicine (CM) may be effective in treating hyperlipidemia, but there is a lack of studies with high methodological quality. A major reason for this is heterogeneity in outcome reporting. Therefore, this study explores the degree of outcome reporting variation in CM trials for hyperlipidemia. It then generates a list of potentially important outcomes for developing a core outcome set (COS). Methods. A systematic review of literature focusing on studies of CM for hyperlipidemia was conducted. Outcomes were listed verbatim and grouped into 8 domains. Outcome frequency and definition uniformity were analyzed. Results. 3,702 studies and 452 individual outcomes were identified. These outcomes were reported 27,328 times, of which 1.6% were reported as primary outcomes, and 13.3% were defined. The most frequent outcome was total triglyceride, represented in 86.7% of the studies, followed by total cholesterol (86.0%), total effective rate (75.1%), high-density lipoprotein cholesterol (73.2%), and low-density lipoprotein cholesterol (60.5%). However, 43.6% of outcomes were reported only once. The largest outcome domain was "pathological or pathophysiological outcomes," which included 67.0% of outcomes. Of the "response rate related outcomes" domain, total effective rate was the most frequently reported outcome (n = 2,780), and 95.3% of the studies gave a clear definition. However, these definitions were often contradictory. Only 10 papers reported cardiovascular events, 3 of which referred to them as primary outcomes. Moreover, ten patient-reported outcomes were reported in the retrieved literature 19 times in total. The majority of the outcomes did not report measurement instruments (MIs) (269/453, 59.4%). MIs of the surrogate outcomes were reported more frequently. Conclusion. Outcome reporting in CM trials for hyperlipidemia is inconsistent and ill-defined, creating barriers to data synthesis and comparison. Thus, we propose and are developing a COS for CM trials for hyperlipidemia. [ABSTRACT FROM AUTHOR]

In this paper, we study the FCNC decay processes of B and B c meson, in which one invisible particle is emitted. Both the spin-0 and spin-1 cases are considered. The model-independent effective Lagrangian is introduced to describe the coupling between the light invisible boson and quarks. The constraints of the coupling coefficients are extracted by experimental upper limits of the missing energy in B meson decays. The bounds are used to predict the upper limits of branching fractions of corresponding B c decays, which are of the order of 10 - 6 or 10 - 5 when final meson is pseudoscalar or vector, respectively. The maximum branch ratios are achieved when m χ ≈ 3.5 –4 GeV, where m χ is the mass of the invisible particle. [ABSTRACT FROM AUTHOR]

The objective of this work is to study the effect of strain gradient, electric field gradient, and magnetic field gradient on the potential and field distributions of multiferroic fibrous composites subjected to generalized anti-plane shear deformation. A detailed energy variational formulation with strain, strain gradient, electric field, electric field gradient, magnetic field, and magnetic field gradient as independent variables is provided, and the equilibrium equations with the complete boundary conditions are simultaneously determined. Three internal characteristic lengths of the underlying microstructure are introduced in the constitutive equations. The general solutions in cylindrical polar coordinates consisting of the modified Bessel functions of first and second kind are derived. One inclusion problem's solution is also obtained. The derived solutions are applied to a CoFe 2 O 4 -PZT-4 composite to demonstrate the effect of strain gradient, electric field gradient, and magnetic field gradient. Numerical results provide insights into the role of characteristic lengths on the potential and field distributions of a multiferroic fibrous composite. [ABSTRACT FROM AUTHOR]

In recent years, advanced oxidation technologies employ peroxynitrite activation have exhibited exceptional effectiveness in eliminating various emerging contaminants. In this study, different calcination temperatures were used to derive Co 3 O 4 nanospheres with varying surface morphologies. This method effectively addresses the issue of high cost associated with high-performance catalyst synthesis or poor catalytic performance of low-cost catalysts. The active species like O 2 •−, •OH, SO 4 •−, 1O 2 played significant role in TC degradation and 1O 2 was the dominant reactive oxygen species (ROS). The study also proposed possible degradation pathways based on the 15 intermediates identified through HPLC-MS. Furthermore, the developmental toxicity of the identified intermediates was evaluated using a quantitative conformational relationship prediction method. This paper delves into the reaction mechanism of Co 3 O 4 nanospheres in the activation of PMS and examines the impact of surface morphology on their catalytic performance, providing a new approach to developing a persulfate catalyst that is cost-effective and has high catalytic performance, with a simple synthesis step. [Display omitted] • Different surface morphologies of Co 3 O 4 are synthesized at various temperatures. • Co-T produced at 300 °C has the best catalytic performance. • The mechanism of Co-T enhanced degradation of TC by PMS was discussed. • The possible TC degradation pathways are proposed. [ABSTRACT FROM AUTHOR]

Background: Epidemiological studies have shown that young women often suffer from primary dysmenorrhea (PD) which is a common cause that affects their routine work and quality of life. Chinese herbal medicine has been widely used for PD in China. A systematic review found that Xuefu Zhuyu (XFZY) has a promising effect on PD management, yet there is a dearth of high-quality evidence in support of this claim. We want to conduct a randomized controlled trial to evaluate the efficacy and safety of XFZY for PD patients.Methods: This is a protocol for a multicenter, randomized, placebo-controlled trial. A total of 248 participants with PD will be recruited at 6 centers and randomized into two groups-a herbal treatment group and a placebo group. The participants will receive either XFZY or placebo, three times per day, for 3 menstrual cycles, with a 12-week follow-up. The primary outcome will be the mean change in pain intensity as measured by VAS, while the change in menstrual pain duration, the change in peak pain intensity as measured by VAS, the Cox Menstrual Symptom Scale (CMSS), quality of life EQ-5D-5L, cumulative painkiller consumption, and health economics will be included as secondary outcomes. Adverse events will also be reported.Discussion: This protocol describes a multicenter, double-blind, randomized, placebo-controlled trial that investigates the efficacy and safety of XFZY for primary dysmenorrhea. Validated evaluation tools will assess dysmenorrhea severity. We believe that this research will provide important evidence regarding the use of XFZY to treat dysmenorrhea.Trial Registration: Chinese Clinical Trial Registry ChiCTR1900026819 . Registered on 23 October 2019. [ABSTRACT FROM AUTHOR]

Piezoelectric actuators play an important role in modern electronic devices. In this work, 0.7Bi(1−x)SmxFeO3–0.3BaTiO3 lead-free piezo-ceramics are fabricated through the rapid thermal quenching technique for enhancing the electric-field-induced strain response. All the ceramic samples own a typical perovskite structure, and the morphotropic phase boundary can be achieved after Sm substitution. Additionally, a high TC of 403 °C and excellent ferroelectricity can be obtained at room temperature for the x = 0.03 composition, together with a large peak-to-peak strain value (∆S = 0.5%). Furthermore, a larger strain value ∆S of 0.45% at 150 °C can also be realized in 0.7Bi0.95Sm0.05FeO3–0.3BaTiO3 ceramic. Our results could further stimulate the investigations on lead-free ceramics for piezoelectric actuator applications. [ABSTRACT FROM AUTHOR]

Dexmedetomidine (DEX) is widely used in perioperative settings for analgesia and sedation; however, little is known about its effects on the hypoxia-induced progression of tumor cells. In the present study, the effects of DEX on hypoxia-induced growth and metastasis of lung cancer cells and colorectal cancer cells was examined. A549 cells and HCT116 cells were treated with normoxia, hypoxia, co-treatment of hypoxia and DEX, and atipamezole (an α2 adrenoceptor antagonist) for 4 h. The proliferation rate of cells was determined by MTT assays. Cell metastatic potential was evaluated by Transwell assays. Survivin and hypoxia inducible factor (HIF)-1α were detected by western blotting. Matrix metalloproteinase (MMP)-2 and MMP-9 were measured using reverse transcription-quantitative PCR. It was demonstrated that hypoxia treatment promoted the proliferation and may promote the metastasis of the two cancer cell lines. DEX substantially contributed to the survival and aggressiveness of the two cancer cell lines following hypoxia. Furthermore, DEX upregulated the expression of survivin, MMP-2, MMP-9 and HIF-1α in the two cancer cell lines in response to hypoxia. Finally, the effects of DEX on the hypoxia-induced growth and metastatic potential of cancer cells were reversed by atipamezole. Collectively, DEX enhances the hypoxia-induced progression of lung cancer cells and colorectal cancer cells by regulating HIF-1α signaling, which may be associated with the α2 adrenoceptor pathway. [ABSTRACT FROM AUTHOR]

Oxidative stress plays an important role in aging-related neurodegeneration. This study used littermates of WT and Nox2-knockout (Nox2KO) mice plus endothelial cell-specific human Nox2 overexpression-transgenic (HuNox2Tg) mice to investigate Nox2-derived ROS in brain aging. Compared with young WT mice (3-4 months), aging WT mice (20-22 months) had obvious metabolic disorders and loss of locomotor activity. Aging WT brains had high levels of angiotensin II (Ang II) and ROS production; activation of ERK1/2, p53, and γH2AX; and losses of capillaries and neurons. However, these abnormalities were markedly reduced in aging Nox2KO brains. HuNox2Tg brains at middle age (11-12 months) already had high levels of ROS production and activation of stress signaling pathways similar to those found in aging WT brains. The mechanism of Ang II-induced endothelial Nox2 activation in capillary damage was examined using primary brain microvascular endothelial cells. The clinical significance of Nox2-derived ROS in aging-related loss of cerebral capillaries and neurons was investigated using postmortem midbrain tissues of young (25-38 years) and elderly (61-85 years) adults. In conclusion, Nox2 activation is an important mechanism in aging-related cerebral capillary rarefaction and reduced brain function, with the possibility of a key role for endothelial cells. [ABSTRACT FROM AUTHOR]

This article aims to analysis high photocatalytic/PMS activation synergy ability of graphitic carbon nitride (g-C 3 N 4) by improving the carriers transfer efficiency and reducing energy band based on controlling the morphology of materials. In this study, tubular g-C 3 N 4 (TCN) with porous structure was prepared by an acid-induced-assembly step and the photocatalysis/PMS activation effects were discussed. Compared with bulk g-C 3 N 4 (BCN), TCN could exhibit enhanced visible light absorption, effectively inhibit electrons and holes recombination in the system, which significantly improved PMS-assisted visible light catalytic efficiency. 97.15 % Rhodamine B (RhB) and 62.3 % Tetracycline (TC) degradation were achieved within 60 min. In addition, the synergistic effect of PMS activation and TCN photocatalysis has a broad pH application range, which is very beneficial for application in practical aqueous systems. Quenching experiments showed that the synergistic effect of photocatalysis/PMS activation on TCN principally the cause of formating 1O 2. Based on the intermediate products detected by liquid chromatography-mass spectrometry (LC-MS) technology, a possible photodegradation pathway of TC was proposed. This paper provides an original perspective to improve carriers transfer and reduce energy band due to conduct the morphology g-C 3 N 4 , which could further broaden the applications in the field of environmental governance. [Display omitted] • Tubular g-C 3 N 4 (TCN) was prepared by acid-induced-assembly step. • The synergy of photocatalysis-PMS activation on TCN was discussed. • The possible degradation pathways and degradation mechanism were proposed. [ABSTRACT FROM AUTHOR]

Abstract Bio-inspired composites with hexagonal platelet and cylindrical inclusions were studied. A novel algorithm termed staggered hardcore algorithm (SHCA) was used to rapidly generate 3D periodic representative volume elements (RVE) for bio-inspired composites with staggered non-uniformly dispersed inclusions. The spatial dispersions of inclusions in these generated RVEs were assessed using autocorrelation analysis, demonstrating the effectiveness of the SHCA algorithm. Orthotropic elastic properties of two different bio-inspired composites were computed and compared with analytical models, namely modified shear-lag, Mori-Tanaka and Halpin-Tsai, as well as available experimental data from the literature. For lower inclusion volume fractions, the computed results correlated well with experimental data and the analytical results. However, for higher inclusion volume fractions and aspect ratios the analytical results diverged, particularly Mori-Tanaka and modified shear-lag models which was similarly reported in previous studies. The capabilities of the computational model were further demonstrated through a comparative study of orthotropic elastic constants for the cylindrical and hexagonal inclusion composites. The study revealed the necessity to use 3D micromechanical models with realistic inclusion dispersions for accurately assessing the response of high inclusion volume fraction bio-inspired composites. [ABSTRACT FROM AUTHOR]

In this study, the main defect, i.e., lack of fusion (LOF), occurring at the sidewalls in narrow gap laser-arc hybrid welding (NGHW) was confirmed to depend on the cross-sectional shape of previous pass, which was classified into four types, namely concave, convex, middle convex, and inclined shapes. Only the concave shape was effective in suppressing the LOF because the sharp corner between the weld and sidewalls could not be completely filled by next pass in the other three types. The effects of the welding parameters on the concave degree of weld cross-sectional shape were obtained from the dimensionless analysis related to the driving forces in the molten pool. It was found that the welding parameters, namely the arc current, welding speed, and groove width had a significant effect on the concave degree, whereas the laser power and laser-arc distance had no direct effect. A semi-quantitative criterion was proposed to predict the occurrence of the LOF. The LOF was suppressed when the ratio of the electromagnetic force to the liquid viscosity force was larger than 3.21 × 105, and the ratio of the surface tension gradient to the liquid viscosity force was larger than 1.28 × 104. The suppression mechanism of the LOF in NGHW was discussed in terms of the forces and melt flow in the molten pool. [ABSTRACT FROM AUTHOR]

We use ab initio calculations to explore the geometry, bonding and electronic properties of Mxene/blue phosphorene (BLP) heterobilayers. Perfect lattice-matched and energetically stable Mxene/BLP heterobilayers are firstly predicted to be vertically stacked with less than 1% lattice mismatch. The electronic properties of the heterobilayers are consistent with the substrate Mxene and the states projected on the isolated components are preserved. The unchanged electronic properties for the components upon the formation of the heterobilayers indicate the physical vdW interaction between the BLP monolayers and Mxene sheet, instead of the chemical bonds. The most stable BLP/Y 2 CX 2 (X = O, and Y = Hf, Zr) are found to be a semiconductor with a type-II band alignment where the excited electrons and holes are localized in different layers. However, for BLP/Y 2 CX 2 (X = F, and Y = Hf, Zr), the most stable structure is metallic with a strong band bending which lead to the existence of a partial flat band along the Γ point to the M point that mainly originates from the BLP monolayes. The appearance of the spatial separation of electron and hole and the partial flat band in these heterostructures have potential applications in optoelectronic devices and strong electron-electron correlation field. Our analysis also suggests that Mxene is a promising substrate to grow BLP monolayer epitaxially. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel ultrathin porous Bi 2 WO 6 with rich surface oxygen vacancies is reported. • The oxygen vacancies promote the O 2 chemisorption and electron transfer. • The ultrathin porous structure enhances the adsorption capacity of V O -rich BWO to tetracycline molecules. • The ultrathin porous Bi 2 WO 6 nanosheets have a degradation efficiency approximately 52.6 times than bulk Bi 2 WO 6. Exploring advanced photocatalysts for antibiotics degradation is highly desired but remains a challenge due to the lack of reasonable structural design and molecular oxygen activation. Herein, we deliberately design novel ultrathin porous Bi 2 WO 6 with rich surface oxygen vacancies (V O -rich BWO) to enhance the tetracycline adsorption and photocatalytic reactive oxygen species generation. The oxygen vacancies in V O -rich BWO can narrow its bandgap to enhance the light absorption and introduce defect level, which can promote electron separation and transfer. Furthermore, the multiplication of oxygen vacancies increases the adsorption energy of O 2 , thus enhancing the chemisorption of O 2 , thereby activating O 2 to produce more •O 2 −. Meanwhile, the porous structure enhances the adsorption capacity of V O -rich BWO to tetracycline molecules, allowing for a more efficient use of the •O 2 −. Taking advantage of the synergy, the rich oxygen vacancies Bi 2 WO 6 nanosheets are able to degrade adsorbed tetracycline in situ with a degradation efficiency approximately 52.6 times that of bulk BWO, thus holding great potential for removing organic pollutants. [ABSTRACT FROM AUTHOR]

Generating realistic non-uniformly distributed three-dimensional representative volume element (RVE) for modeling the response of high fiber volume fraction composites is challenging. A novel rapid approach employing a random event-driven molecular dynamics simulation (EDMD) was proposed in this study for this purpose. Distributions of continuous unidirectional fibers in the RVEs were assessed using two approaches, namely Voronoi tessellations and radial distribution functions. The developed method was highly efficient in generating RVEs with realistic fiber dispersions. Furthermore, applying the corresponding periodic boundary conditions (PBCs) for finite element modeling is also arduous. A technique was developed within the commercial finite element software ABAQUS to rapidly produce required matching mesh patterns on opposite surfaces of the RVE, and to apply the corresponding PBCs using custom scripts. By coupling the EDMD approach and custom scripts within ABAQUS to rapidly generate and mesh RVEs with high fiber volume fractions, evaluation of the RVE response was greatly simplified. In- and out-of-plane elastic properties of unidirectional glass/epoxy composite in a range of 10–80% fiber volume fractions were determined and compared with analytical models, and available experimental data, with good correlation. [ABSTRACT FROM AUTHOR]

The hepatic VX2 carcinoma model in rabbits is widely used for the preclinical study of hepatocellular carcinoma. In the present study, a modification was made to the conventional method to establish the animal model, as the conventional method gives rise to frequent tumor seeding due to the drop-out of tumor fragments. In order to evaluate each distinct method of establishing the model, the rabbits were divided into two groups: Group A (the conventional method; n=20) and group B (the modified method; n=20). All surgical details were recorded for reference. At 14 days post-surgery, contrast-enhanced computed tomography (CECT) and autopsy were conducted. Microscopic morphology of tumor cells was observed using hematoxylin and eosin (H&E) and transmission electron microscopy (TEM). Vascular endothelial growth factor (VEGF) and cluster of differentiation (CD)31 were detected via immunochemistry and reverse transcription-polymerase chain reaction. In total, 19 rabbits in each group succeeded in model establishment. Throughout the surgery, group A experienced a longer surgery time compared with group B (group A vs. group B, 22.57±1.34 vs. 20.17±1.50 min; P<0.001), an increased tumor fragment drop-out frequency (group A vs. group B, 1.84±0.96 vs. 1.16±0.38; P=0.008) and an increased peritoneal nodule incidence (group A vs. group B, 35 vs. 5%, P=0.042). As for CECT, H&E and TEM, hepatic VX2 allografts in the two groups demonstrated similar imaging presentations and tumor cell morphology. In addition, VEGF and CD31 levels did not differ between the two groups. In conclusion, the modified method for the establishment of hepatic VX2 carcinoma model in rabbits may decrease tumor fragment drop-out frequency during surgery and incidence of tumor seeding without affecting the properties of VX2 carcinoma. [ABSTRACT FROM AUTHOR]

In order to investigate the largest motor vehicle ownership load within the scope of a city with atmospheric environmental indicators as constraint, this article estimates traffic atmospheric environmental capacity (TAEC) and carrying capacity (TAECC) in Tianjin using the A-value method recommended by the Chinese national standard. Our results indicate that NO X carrying capacity is a key restraining factor of TAEC. According to the current vehicle emission levels per year and air quality standard, Tianjin can accommodate 4.21 million vehicles. Classified by the vehicle type, heavy trucks and large-sized passenger cars are identified as the most important restrictive factors of TAECC. Then we analyze change of TAECC and TAECC’s service life under the circumstances of clean vehicle strategy and mobility management strategy. Clean vehicles strategy represented by the elimination of heavy-polluting vehicles can reduce emissions of vehicles so that it can rapidly enhance the TAECC in the short term. Mobility management strategy represented by the car purchase restriction, which reduces total motor vehicle travel, is indispensable for improvement of TAECC in the long term. On the whole, the clean vehicles strategy and mobility management strategy should be implemented gradually. [ABSTRACT FROM AUTHOR]

We study the invisible scalar of S in charmed meson and baryon decays with flavor-changing neutral currents (FCNCs) based on the model-independent effective Lagrangian between the quarks and invisible scalar. From the bounds of the coupling constants extracted from the recent BES III experiment on the decay of D 0 → π 0 ν ¯ ν , we predict that the decay branching ratios of D + → π + S , D s + → K + S , Λ c → p S , Ξ c 0 (+) → Σ 0 (+) S , and Ξ c 0 → Λ S can be as large as 10.6 , 2.53 , 2.39 , 0.963 , 5.77 , and 2.92 × 10 − 4 with m S ≈ 1.1 GeV , respectively. Some of these decay modes are accessible to the ongoing experiments, such as BES III, LHCb and Belle II, as well as the future ones, such as FCC-ee. [ABSTRACT FROM AUTHOR]

A Ruddlesden–Popper oxide (Pr 0.9 La 0.1 ) 2 (Ni 0.74 Cu 0.21 Nb 0.05 )O 4+δ (PLNCN)-infiltrated BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ (BZCY) is developed as an electrode for protonic ceramic fuel cells (PCFCs). PLNCN nanoparticles are evenly dispersed on the surface of BZCY skeleton by using the infiltration technology. The electrochemical behavior of the PLNCN-infiltrated BZCY electrodes are evaluated in terms of infiltration loading and temperature. The impedance results of symmetric cells suggest that the optimized loading of PLNCN is approximately 46.1 wt%. Power density of the single cell as high as 0.77 W cm −2 is achieved at 700 °C by using the 43.6 wt% PLNCN-infiltrated BZCY cathode, and the cell could be operated without degradation at 600 °C for 200 h; this finding indicates a promising alternative cathode for PCFCs. [ABSTRACT FROM AUTHOR]

To help better interpret computational models in predicting drift of carp eggs in rivers, we present a series of model assessments for the longitudinal egg dispersion. Two three-dimensional Lagrangian particle tracking models, SDrift and FluEgg, are evaluated in a series of channels with increasing complexity. The model evaluation demonstrates that both models are able to accommodate channel complexity and provide a wide range of dispersion coefficients: K l = O (1 − 100) H u ∗ with H being water depth and u ∗ being shear velocity. In a straight channel with K l = O (1) H u ∗ , SDrift predicts weaker longitudinal dispersion than FluEgg in the early stage as a result of weak vertical mixing associated with smooth wall turbulence. With sufficient time, SDrift and FluEgg predict similar egg dispersion, accounting for the differential advection due to the vertical velocity profile. In an idealized curved channel with K l = O (10) H u ∗ , dispersion is driven by both vertical and transverse velocity profiles. SDrift yields slightly larger dispersion coefficients than FluEgg. In a real river with channel-training structures and having K l = O (100) H u ∗ , SDrift predicts a stronger longitudinal dispersion than FluEgg due to substantial local turbulent eddies and velocity gradients. To summarize, FluEgg shows good performance in capturing dispersion due to vertical velocity profiles and cross-channel velocity gradients. SDrift shows excellent model capabilities of revealing various dispersion mechanisms in addition to the vertical and cross-channel velocity variations. They include the initial turbulent diffusion stage with growing dispersion coefficients and strong dispersion due to in-stream hydraulic structures and localized turbulence. • Two Lagrangian egg drift models, FluEgg and SDrift, are evaluated in a series of channels with increasing complexity. • Both models can accommodate channel complexity to predict the fluvial egg dispersion process. • SDrift can provide a realistic representation of various dispersion mechanisms in different channels and rivers. [ABSTRACT FROM AUTHOR]

Sm 0.5 Sr 0.5 CoO 3−δ (SSC) infiltrated Ce 0.9 Gd 0.1 O 2−δ (GDC) composite cathodes are developed for protonic ceramic fuel cells (PCFCs). Although the SSC infiltrated GDC cathodes make little contribute to expending the reaction sites of water formation, it can significantly improve the oxygen reduction dynamics among the whole electrochemical reaction. The symmetric half cell and single cell testing results demonstrate the high electrochemical activity of SSC infiltrated GDC cathodes. Moreover, the single cell is stable at 600 °C for 120 h in humidified H 2 and humidified H 2 CO. The encouraging results indicate that the SSC infiltrated GDC could be the promising composite cathodes for application in PCFCs. [ABSTRACT FROM AUTHOR]

[Display omitted] • La 2 Ti 2 O 7 -In 2 O 3 photocatalyst has been constructed via the interface band structure engineering. • La 2 Ti 2 O 7 -In 2 O 3 shows excellent photocatalytic activity on CIP degradation with good photostability and recyclability. • The interfacial engineering accelerates the charge direction transfer process. • La 2 Ti 2 O 7 -In 2 O 3 can generate ·OH and ·O 2 – efficiently via Z-scheme mechanism. Interfacial regulation in solar-light-responsive heterostructures is considered an effective strategy to address efficient charge transfer. However, the conscious design of interfacial engineering is still a great challenge. Herein, sandwich-like La 2 Ti 2 O 7 /In 2 O 3 hierarchical tubular heterostructure was reasonably designed to modulate the interface structure for efficient photocatalytic ciprofloxacin degradation. Systematic investigations reveal that the Z-scheme charge transfer mechanism is affirmed using the electron paramagnetic resonance spectra, density functional theory calculations and in-situ irradiated XPS spectra. The hierarchical tubular heterostructure is responsible for improved light absorption and active sites, while the strong interfacial interaction can induce the separation and migration of photogenerated charges. Thus, the optimized photocatalyst exhibits high ciprofloxacin degradation rate of 98.2% in 100 min with a pseudo-first-order rate constant of 0.0408 min−1, which is about 98.05-fold and 38.86-fold of the pristine In 2 O 3 and La 2 Ti 2 O 7 , respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • La 2 Ti 2 O 7 -In 2 O 3 photocatalyst has been constructed via the interface band structure engineering. • La 2 Ti 2 O 7 -In 2 O 3 shows excellent photocatalytic activity on CIP degradation with good photostability and recyclability. • The interfacial engineering accelerates the charge direction transfer process. • La 2 Ti 2 O 7 -In 2 O 3 can generate ·OH and ·O 2 – efficiently via Z-scheme mechanism. Interfacial regulation in solar-light-responsive heterostructures is considered an effective strategy to address efficient charge transfer. However, the conscious design of interfacial engineering is still a great challenge. Herein, sandwich-like La 2 Ti 2 O 7 /In 2 O 3 hierarchical tubular heterostructure was reasonably designed to modulate the interface structure for efficient photocatalytic ciprofloxacin degradation. Systematic investigations reveal that the Z-scheme charge transfer mechanism is affirmed using the electron paramagnetic resonance spectra, density functional theory calculations and in-situ irradiated XPS spectra. The hierarchical tubular heterostructure is responsible for improved light absorption and active sites, while the strong interfacial interaction can induce the separation and migration of photogenerated charges. Thus, the optimized photocatalyst exhibits high ciprofloxacin degradation rate of 98.2% in 100 min with a pseudo-first-order rate constant of 0.0408 min−1, which is about 98.05-fold and 38.86-fold of the pristine In 2 O 3 and La 2 Ti 2 O 7 , respectively. [ABSTRACT FROM AUTHOR]

The removal of algae by reactive oxygen species (ROS) through photocatalytic O 2 activation is still a challenge. Herein, we constructed a van der Waals (VDW) heterojunction photocatalyst by coupling BiO 2−x with Bi 3 NbO 7 for photocatalytic inactivation of Microcystic aeruginosa and photodegradation of Microcystin-LR. The oxygen vacancies in BiO 2−x /Bi 3 NbO 7 can effectively promote the chemisorption of O 2 , and the VDW force can drive the photoelectrons in Bi 3 NbO 7 transfer to BiO 2−x through S-scheme transfer path, resulting more electrons reduce O 2 to·O 2 -. Hence, photocatalytic inactivation of algae by BiO 2−x /Bi 3 NbO 7 is 14.17 and 19.05 times higher than BiO 2−x and Bi 3 NbO 7 , respectively. During the photocatalysis, the·O 2 - damages the antioxidant system and cell membrane of algae, resulting in the release of organic matter and Microcystin-LR and finally causing the death of algae. The three-dimensional fluorescence spectroscopy indicates BiO 2−x /Bi 3 NbO 7 can further availably photodegrade the organic matter, and four possible photodegradation pathways of MC-LR are proposed. [Display omitted] • The BiO 2−x and Bi 3 NbO 7 based 2D/2D novel Van der Waals heterostructure is reported. • The oxygen vacancies in BiO 2−x /Bi 3 NbO 7 can promote the chemisorption of O 2. • BiO 2−x /8.0Bi 3 NbO 7 shows the best photocatalytic inactivation of algae. • Charge separation in VDW heterojunction is enhanced via S-scheme mechanism. • Photocatalytic inactivation mechanism of algae is proposed. [ABSTRACT FROM AUTHOR]

Grass carp, bighead carp, and silver carp spawn in flowing water. Their eggs, and then larvae, develop while drifting. Hydraulic conditions and water temperature control spawning locations, egg survival, and the downstream distance traveled before the hatched larvae can swim for low velocity nursery habitats. Existing egg drift models simulate the fluvial transport of carp eggs but have limitations in capturing the effect of localized turbulence on egg transport due to inadequate dimensions of hydrodynamics and/or empirical parameterization of river dispersion. We present a three-dimensional Lagrangian particle tracking model that uses fully resolved river hydrodynamics and a continuous random walk algorithm driven by local turbulent kinetic energy and its dissipation rate. We incorporate a new set of equations to compute evolving egg characteristics with fully resolved 3-D hydrodynamics. To demonstrate the performance of the model, we conducted a case study in an eight-kilometer reach of the Missouri River at the discharge of approximately 25% daily flow exceedance. Three-dimensional river hydrodynamics was modeled, calibrated, and evaluated with measurement data. Egg drift was modeled and compared using fully three-dimensional, depth-averaged two-dimensional, and zone-averaged one-dimensional hydrodynamics. The comparison shows a generally good agreement among models of downstream egg transport due to advection but a different dispersion pattern of eggs in the river, as a result of turbulent diffusion and shear induced dispersion. • A model was developed to simulate drifting of fish eggs in large rivers. • The effects of localized turbulence on egg drift are included in the model. • Turbulent transport is modeled using realistic particle tracking algorithms. [ABSTRACT FROM AUTHOR]

Objective: this paper was aimed to study the separation and purification of yeast glucose tolerance factor (GTF) and its effect on intracorporal glucose conversion of body builders. Methods: Yeast high-yield GTF was adopted in order to improve the detection sensitivity of chromium; in separation and purification process, the method high performance liquid chromatography- inductively coupled plasma- mass spectrometry/ atomic emission spectrometry (HPLC-ICPMS/ AES) was applied in microanalysis of the distribution of GTF; according to the analysis results, appropriate separation technique was selected for batch separation and purification; by comparing the blood indexes of fed mice, intracorporal glucose conversion of body builders could be deduced. Results: Chromium/ protein ratio of Peak 1 was much lower than that of Peak 2; Peak1 was micromolecular chromium-binding protein, while Peak 2 was micromolecular chromium-binding protein. N-terminal amino acid sequence analysis results of peak PP1 showed that amino acids in peak PP1 were probably connected with chromium by coordination bonds instead of peptide bonds. In addition, triglyceride and cholesterol level in blood decreased. Conclusion: Chromium-enriched yeast has an improvement effect on diabetes to some degree. [ABSTRACT FROM AUTHOR]

The effects of beam oscillating parameters on weld morphologies are investigated. Weld geometrical sizes were counted statistically. The results showed that the difference in cross-section width from the top to the lower gradually reduced to disappear with the increase of oscillating frequency. Weld cross-section was featured by slender nail when the frequency was 10 Hz or so, which was similar with conventional laser keyhole weld. It changed to dumpy nail, V-shape and U-shape in sequence with the increase of the frequency within the range from 20 Hz to 1000 Hz. The welding speed thresholds transforming the welding from keyhole mode to unstable mode and from unstable mode to heat conduction mode were confirmed as 24 m/min and 48 m/min, respectively. Weld formation mechanisms were summarized by weld overlapping ratio and the transformation of welding mode. [ABSTRACT FROM AUTHOR]

With the increase of service years, external walls of high-rise buildings tend to suffer from a variety of defects which impose great safety risks. Traditional methods for inspecting high-rise building external walls require inspectors to work at height and identify defects manually, which is dangerous and inefficient. In recent years, there has been an increasing trend of using unmanned aerial vehicles (UAV) for inspecting building external walls, but how to manage the information obtained by the UAV is still a problem. In addition, although building information modelling (BIM) with rich geometric and semantic information has been applied in the construction engineering industry, BIM models usually lack updated condition data of facilities. Therefore, this paper presents a method for managing the inspection results of building external walls by mapping defect data from UAV images to BIM models and modelling defects as BIM objects. First, images of building external walls obtained by UAV are processed and useful information such as coordinates are extracted. Considering the small scale of single buildings, a simplified coordinate transformation approach is developed to transform location of real-world defects to coordinates in the BIM model. Meanwhile, a deep learning-based instance segmentation model is developed to detect defects in the captured images and extract their features. In the end, the identified defects are modelled as new objects with detailed information and mapped to the corresponding location of the related BIM component. To validate the feasibility, the proposed method has been applied to a real office building, which successfully mapped and integrated the defects of external walls with the BIM model. This study is applicable to both buildings and infrastructure, and is expected to facilitate structure inspection and decision making in maintenance with integrated data of as-is condition and as-built BIM. • Proposed a framework for mapping and modelling defect data from UAV images to BIM. • Developed a coordinate transformation method to map real-world data to BIM model. • Developed a deep learning model to detect and segment building wall defects in images. • Modelled defects of building wall as BIM objects with detailed features. [ABSTRACT FROM AUTHOR]

Aims Phosphatidylinositol 3 kinases (PI3Ks) play a pivotal role in vascular physiology and pathophysiology. We aimed to investigate the role of p55γ, a regulatory subunit of PI3Ks, in vascular smooth muscle cell (VSMC) proliferation and neointimal formation. Methods and results We identified p55γ as an important factor that suppresses VSMC proliferation and injury-evoked neointimal formation. Western blot and mRNA analyses showed that p55γ expression declined in balloon-injured rat carotid arteries and in response to PDGF-BB and serum treatment in cultured VSMCs. Overexpression of p55γ inhibited, whereas short hairpin RNA knockdown of p55γ promoted PDGF-BB- and serum-induced VSMC proliferation. Importantly, in vivo adenoviral gene transfer of p55γ into carotid arteries attenuated, while knockdown of p55γ enhanced balloon injury-induced neointimal formation. Furthermore, p55γ sequentially up-regulated p53 and p21, resulting in cell-cycle arrest in S phase; small-interfering RNA knockdown of either p53 or p21 blocked p55γ-induced VSMC growth arrest. Mechanistically, p55γ interacted with and stabilized p53 protein by blocking mouse double minute 2 homologue-mediated p53 ubiquitination and degradation, subsequently activating its target gene p21. Concurrently, p55γ up-regulated Bcl-xl expression, resulting in non-apoptotic growth arrest effect. Conclusion These findings mark p55γ as a novel upstream regulator of the p53-p21 signalling pathway that negatively regulates VSMC proliferation, suggesting that malfunction of p55γ may trigger vascular proliferative disorders. [ABSTRACT FROM PUBLISHER]

The symmetry breaking observed in nature is fascinating. This symmetry breaking is observed in both human crowds and ant colonies. In such cases, when escaping from a closed space with two symmetrically located exits, one exit is used more often than the other. Group size and density have been reported as having no significant impact on symmetry breaking, and the alignment rule has been used to model symmetry breaking. Density usually plays important roles in collective behavior. However, density is not well-studied in symmetry breaking, which forms the major basis of this paper. The experiment described in this paper on an ant colony displays an increase then decrease of symmetry breaking versus ant density. This result suggests that a Vicsek-like model with an alignment rule may not be the correct model for escaping ants. Based on biological facts that ants use pheromones to communicate, rather than seeing how other individuals move, we propose a simple yet effective alarm pheromone model. The model results agree well with the experimental outcomes. As a measure, this paper redefines symmetry breaking as the collective asymmetry by deducing the random fluctuations. This research indicates that ants deposit and respond to the alarm pheromone, and the accumulation of this biased information sharing leads to symmetry breaking, which suggests true fundamental rules of collective escape behavior in ants. [ABSTRACT FROM AUTHOR]

Summary Sound-evoked spikes in the auditory nerve can phase-lock with submillisecond precision for prolonged periods of time. However, the synaptic mechanisms that enable this accurate spike firing remain poorly understood. Using paired recordings from adult frog hair cells and their afferent fibers, we show here that during sine-wave stimuli, synaptic failures occur even during strong stimuli. However, exclusion of these failures leads to mean excitatory postsynaptic current (EPSC) amplitudes that are independent of Ca 2+ current. Given the intrinsic jitter in spike triggering, evoked synaptic potentials and spikes had surprisingly similar degrees of synchronization to a sine-wave stimulus. This similarity was explained by an unexpected finding: large-amplitude evoked EPSCs have a significantly larger synchronization index than smaller evoked EPSCs. Large EPSCs therefore enhance the precision of spike timing. The hair cells’ unique capacity for continuous, large-amplitude, and highly synchronous multiquantal release thus underlies its ability to trigger phase-locked spikes in afferent fibers. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) are a class of small, noncoding RNAs that act as key regulators in various physiological and pathological processes. However, the regulatory mechanisms for miRNAs in colorectal cancer remain largely unknown. Here, we found that miR-103 is up-regulated in colorectal cancer and its overexpression is closely associated with tumor proliferation and migration. In addition, repressing the expression of miR-103 apparently inhibits colorectal cancer cell proliferation and migration in vitro and HCT-116 xenograft tumor growth in vivo. Subsequent software analysis and dual-luciferase reporter assay identified two tumor suppressor genes DICER and PTEN as direct targets of miR-103, and up-regulation of DICER and PTEN obtained similar results to that occurred in the silencing of miR-103. In addition, restoration of DICER and PTEN can inhibit miR-103-induced colorectal cancer cell proliferation and migration. Our data collectively demonstrate that miR-103 is an oncogene miRNA that promotes colorectal cancer proliferation and migration through down-regulation of the tumor suppressor genes DICER and PTEN. Thus, miR-103 may represent a new potential diagnostic and therapeutic target for colorectal cancer treatment. [ABSTRACT FROM AUTHOR]

In order to solve some common problems of CNC-machined spiral bevel gears such as small cutting strip width and poor surface quality, while milled by the ball-end, a machining method of face milling using a disk cutter with a concave end is presented. The research theories are based on the foundation of spiral bevel gears' geometry structure. Firstly, a bigger diameter disk cutter with a concave end is selected. Then, change the setting order of cutter orientation angles. The functions of cutter tilt and yaw angle are separated, and tooth surfaces machined with big cutting strip width and no bottom land gouge can be expected. Since the cutter yaw angle, determined firstly by cutting contact point, positions in the tooth surface machine, the bottom land gouge interference can be avoided effectively. Then, the tilt angles of the gear pair, both side tooth surfaces, are determined by the theory of sculptured surfaces machined by the flat-end cutter, respectively. As a result, the improved cutting strip width and machining efficiency can be realized. Finally, feasibility of this method is verified through machining experiment and measurement of a spiral bevel gear pair. [ABSTRACT FROM AUTHOR]

Hair cell synapses in the ear and photoreceptor synapses in the eye are the first synapses in the auditory and visual system. These specialized synapses transmit a large amount of sensory information in a fast and efficient manner. Moreover, both small and large signals with widely variable kinetics must be quickly encoded and reliably transmitted to allow an animal to rapidly monitor and react to its environment. Here we briefly review some aspects of these primary synapses, which are characterized by a synaptic ribbon in their active zones of transmitter release. We propose that these synapses are themselves highly specialized for the task at hand. Photoreceptor and bipolar cell ribbon synapses in the retina appear to have versatile properties that permit both tonic and phasic transmitter release. This allows them to transmit changes of both luminance and contrast within a visual field at different ambient light levels. By contrast, hair cell ribbon synapses are specialized for a highly synchronous form of multivesicular release that may be critical for phase locking to low-frequency sound-evoked signals at both low and high sound intensities. The microarchitecture of a hair cell synapse may be such that the opening of a single Ca2+ channel evokes the simultaneous exocytosis of multiple synaptic vesicles. Thus, the differing demands of sensory encoding in the eye and ear generate diverse designs and capabilities for their ribbon synapses. [ABSTRACT FROM AUTHOR]

Summary: Heterochromatin assembly in budding yeast requires the SIR complex, which contains the NAD-dependent deacetylase Sir2 and the Sir3 and Sir4 proteins. Sir3 binds to nucleosomes containing deacetylated histone H4 lysine 16 (H4K16) and, with Sir4, promotes spreading of Sir2 and deacetylation along the chromatin fiber. Combined action of histone modifying and binding activities is a conserved hallmark of heterochromatin, but the relative contribution of each activity to silencing has remained unclear. Here, we reconstitute SIR-chromatin complexes using purified components and show that the SIR complex efficiently deacetylates chromatin templates and promotes the assembly of altered structures that silence Gal4-VP16-activated transcription. Silencing requires all three Sir proteins, even with fully deacetylated chromatin, and involves the specific association of Sir3 with deacetylated H4K16. These results define a minimal set of components that mediate heterochromatic gene silencing and demonstrate distinct contributions for histone deacetylation and nucleosome binding in the silencing mechanism. [Copyright &y& Elsevier]

The low-molecular-weight and easily prepared N-thiobenzoyl 1-methyl-histidine methyl ester 3k was utilized to efficiently catalyze the kinetic resolution of racemic secondary alcohols. Comparison of the conformations of amide catalyst 3c and thioamide catalyst 3k was made to understand the origin of the improvement of the enantioselectivity by thioamide modification. [ABSTRACT FROM AUTHOR]

Polycomb-group (Pc-G) proteins repress their target gene expression by assemble complexes in Drosophila and mammals. Three groups of Pc-G genes, controlling seed development, flower development and vernalization response, have been identified in Arabidopsis ( Arabidopsis thaliana L.). MEDEA (MEA), FERTILIZATION INDEPENDENT SEED2 ( FIS2), and FERTILIZATION INDEPENDENT ENDOSPERM ( FIE) are Pc-G genes in Arabidopsis. Their functions in seed development have been extensively explored. The advanced findings of molecular mechanism on how MEA, FIS2 and FIE control seed development in Arabidopsis are reviewed in this paper. [ABSTRACT FROM AUTHOR]

Functional magnetic resonance imaging (fMRI) and positron emission tomography (PET) were used to map brain activation during language tasks. While previous studies have compared performance between alphabetic literate and illiterate subjects, there have been no such data in Chinese-speaking individuals. In this study, we used fMRI to examine the effects of education on neural activation associated with silent word recognition and silent picture-naming tasks in 24 healthy right-handed Chinese subjects (12 illiterates and 12 literates). There were 30 single Chinese characters in the silent word recognition task and 30 meaningful road-signs in the silent picture-naming task. When we compared literate and illiterate subjects, we observed education-related differences in activation patterns in the left inferior/middle frontal gyrus and both sides of the superior temporal gyrus for the silent word recognition task and in the bilateral inferior/middle frontal gyrus and left limbic cingulated gyrus for the silent picture-naming task. These results indicate that the patterns of neural activation associated with language tasks are strongly influenced by education. Education appears to have enhanced cognitive processing efficiency in language tasks. Hum Brain Mapp, 2005. © 2005 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]