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To date, the classification of mesiodens has been based on the location, crown orientation, and morphology; however, there is no assistance aid focusing on choosing surgical approach. This study aimed to introduce and evaluate a new surgical assistance aid for mesiodens extraction based on surgical approach. For the retrospective trial part of this study, case data from mesiodens patients who had surgery at the Affiliated Stomatological Hospital was collected, and a new surgical assistance aid was developed. A prospective randomized controlled trial was conducted on mesiodens patients who were seen in our department (patients with one mesiodens were included). The predictor variable was surgical approach either with or without the surgical assistance aid. Subjects were randomized to one of the two study groups. For subjects assigned to the group using the surgical assistance guide, the approach was selected according to the aid detailed in this study. For subjects assigned to the group without the surgical assistant aid, 2 residents chose an approach based on their judgment and review of relevant imaging and physical examination. The preoperative evaluation time, operative time, and complications associated with surgery were recorded separately for the two groups. The age and sex were also recorded. Variables were analyzed using the independent t-test and χ2 test. The level of statistical significance is P <.05. In the retrospective trial part, a new surgical assistance aid for mesiodens extraction was developed based on the ideal surgical approach. In the prospective randomized controlled trial, the experimental group (n = 50) was statistically significant in preoperative evaluation time (4.51 ± 0.34 mins vs 5.43 ± 0.34 mins) and operative time (31.87 ± 5.57 mins vs 36.32 ± 5.28 mins) compared to the control group (n = 50) (P <.001). There was no significant intergroup difference in complications associated with surgery (P >.05). The new surgical assistance aid developed in this study guides surgeons to ease the selection of surgical approaches and shorten the operative time. [ABSTRACT FROM AUTHOR]

It was found that the Na modification is beneficial to the synthesis of Ru single-atomic catalyst anchored on GO Na, which was prepared by one-step hydrothermal process. Importantly, the strong metal-support interaction facilitates the electron transfer from Ru SA to GO Na via d-π conjugation, thus lowering the electron density of Ru SA. Experimental results and DFT calculations confirmed that the low electron density of Ru SA can significantly weaken the absorption of H* intermediates and simultaneously accelerate the desorption of generated H 2 from catalyst surface. As a result, the Ru SA/GO Na displayed exceptional HER activity with an extremely low over-potential of 20 mV at 10 mA cm−2, outperforming the benchmark commercial Pt (21 mV over-potential) and Ru nanoparticles (212 mV over-potential) catalysts. When Eosin Y was employed as a light harvester, this Ru SA/GO Na achieves outstanding photocatalytic hydrogen production with a record-high apparent quantum efficiency of 65.2% at 520 nm. Moreover, single-atomic Pt, Pd, Au and Rh were also successfully anchored on the Na-functionalized GO support, suggesting the universality of Na-induced single-atomic synthesis. This work not only provides an effective method for the synthesis of single-atomic metal catalysts but also establishes the connection between the electronic structures of catalyst and performances. [ABSTRACT FROM AUTHOR]

Thermally induced error has proven to be the major source of machining error for the machine tool working in a non-temperature-controlled workshop. Current research on thermal error modeling and compensation is implemented based on the measured thermal deformation of machine tool, and the data is obtained referring to spindle idling rather than metal cutting condition, resulting in the disadvantages of the established model with low adaptability to varying conditions. In this paper, a modeling and compensation method based on the dimensional error of the machined parts is proposed to address the issue and verified through machine tools in an automatic production line. Compared with the modeling based on thermal deformation, the method formulates a more direct relations between temperature rise and machining error. The thermal error modeling is carried out by measuring the dimension deviation of the inner hole diameter of the motor end cover and the screened representative temperature variables. Meantime, considering the temperature coefficient in model is difficult to converge when modeling with the single-day data, the unified modeling with the multi-day data is realized by improving the conventional multiple linear regression model. Finally, the generalized model used for thermal error compensation in x direction of the machine tool is obtained. The real-time compensation of the thermal error based on the established model is realized with the machine tool machining in mass production. The verification results show that this error modeling and compensation method can reduce the machining error of the end cover by more than 52%, irrespective of experiencing various complicated working conditions. Stability and robustness of the modeling are also validated through application on the other machine tool with the same configuration and real machining over seven days. • Dimensional error of machined parts represents thermal effect of machine tool more directly. • Thermal error modeling with real cutting condition guarantees strong robustness. • A generalized error model arises from processing multiday data obtained on production line. • Thermal error model is duplicable to other machine tool and has stability of prediction accuracy. [ABSTRACT FROM AUTHOR]

The cable-driven system characterized by tendon-sheath structure has been widely applied in the field of flexible actuation due to its lightweight, durability, and flexible layout. However, the inherent issues of friction and backlash in the mechanism result in hysteresis, which impose certain limitations on the application of efficient and high-precision actuation scenarios. In this study, a novel control method of force transmission for tendon-sheath actuation system is proposed, based on modified friction model with compensation parameters. The control method adopts a hybrid control strategy based on inverse model feedforward control, which improves the response time and disturbance rejection capability of the cable-driven system. Real-time detection and compensation of cable bending angles are achieved by introducing an angle identification model, which significantly improves system stability. Experimental results demonstrate that the proposed control strategy increases the response speed and accuracy of the force control for the cable-driven system, with a steady-state maximum peak error of 0.157 N, a step response time of 0.102 s, and a root mean square error of 0.117 N under sinusoidal signals. Finally, the cable-driven actuator and control strategy are applied to the assisted exoskeleton for elbow joint in extravehicular spacesuit, helping wearers overcome joint resistance in working conditions. The results show that when the elbow joint bending angle is 40°, the maximum interaction torque in the bending direction is reduced from 7.94 N m to 0.48 N m, with an average assistance efficiency of 71.8%. The exoskeleton system provides effective assistance to wearers during joint movements and greatly reduces biological energy consumption. • Force tracking control of tendon-sheath system without sheath sensing. • Modified force transmission model with compensation parameters. • Hybrid control strategy based on model with real time identification function. • Elbow joint assistive exoskeleton based on the cable-driven actuator. [ABSTRACT FROM AUTHOR]

[Display omitted] • Feed system thermal error model based on positioning error decoupling is proposed. • Thermally induced error is affected by motion and non-motion heating. • Feed system already has thermal errors when it is not working. • Thermal error model based on MLR has physical meaning and good robustness. • MLR has better accuracy than data-driven models over long time prediction. Thermal error modeling and compensation considering of the measured positioning error decoupling for the lathe with a slant bed is proposed. Due to the complex coupling factors of thermal error, the current compensation methods exhibit limited applicability and generalization. The linear fitting method is used to decouple geometric error and thermal error from the positioning error. The motion heating and non-motion heating experiments of X-direction feed system were carried out to investigate the principle of thermal error generation and the impact factors. The multiple linear regression model of the thermal error was established based on the analysis of the thermal error measurement results. To verify the effectiveness of the proposed model, the thermal error at two working conditions was predicted, and then the error compensation was carried out. The results show that the positioning error is reduced by more than 84% and 92% with the present method compared with that without compensation. This research provides effective method for the generation principle and compensation of thermally induced errors of lathe with a slant bed. [ABSTRACT FROM AUTHOR]

Highlights • Hydration behaviors of the CSP-OPC binary system are investigated comprehensively. • CSP can retard the conversion of AFt to AFm. • CSP can optimize the pore structure of the hardened cement paste at long term curing period. • CSP with 5% can contribute to the early compressive strength of cement mortar. Abstract This study presents the influence of coral sand powder (CSP) on the hydration and mechanical behaviours of Portland cement paste at the curing ages from 1 day to 90 days. The early hydration kinetics of Portland cement incorporated with CSP is studied by isothermal calorimetry test. The hydrates and pore structures of cement paste are determined by X-ray diffraction (XRD) and mercury intrusion porosimetry (MIP), respectively. Experimental results show that CSP can promote acceleration period to end in advance. XRD results imply that CSP can react with tricalcium aluminate (C 3 A) to form monocarbonate (Mc) and hemicarbonate (Hc), which can suppress the conversion of Al-phase products, viz. from AFt to AFm. From the MIP results, the addition of CSP can refine the pore structure of Portland cement paste at long-term curing age, although negative effect of CSP on the total porosity can be observed. Low replacement level of CSP (5 wt%) improves the compressive strength of cement mortar at ages from 1 day to 7 days. However, from 28 days to 90 days, the addition of CSP decreases the strength of cement mortar regardless of replacement levels. [ABSTRACT FROM AUTHOR]

Background Conventional strategies for mycotoxin reduction includes both prevention and decontamination strategies. Decontamination of aflatoxin has been a continuing challenge for the food industry. Novel processing methods are continuously explored to achieve complete aflatoxin degradation in food products. Scope and approach The present review provides an update on recent research for aflatoxin decontamination by conventional methods including thermal processing and chemical treatments. Novel aflatoxin decontamination technologies like microwave heating, gamma and electron beam irradiation, ultraviolet and pulsed light, electrolyzed water and cold plasma are reviewed in detail. This review provides a brief introduction, decontamination mechanism, degradation efficiency, advantages and limitations of these novel technologies. Key findings and conclusion Although conventional thermal technologies are known to cause aflatoxin degradation, they are not adequate for complete aflatoxin degradation in food products. Novel technologies like pulsed light, electrolyzed water and cold plasma have shown complete degradation of aflatoxin on different substrates. However, application on food products need further studies along with the degradant toxicology and its interaction with food components. Novel processing technologies shows significant potential for future applications in decontaminating aflatoxin in the food industry. [ABSTRACT FROM AUTHOR]

In the present paper, density functional theory calculations were carried out on a detailed oxygen reduction reaction (ORR) process catalysed by nitrogen-doped β-graphyne (βGy). Nitrogen-doping can increase the positive charge of the adjacent carbon atom and the graphyne work function, promoting O 2 decomposition. Our calculations revealed that N-doped βGy can efficiently facilitate the ORR process via a four-electron mechanism, regardless of doping position. Additionally, our results revealed that the N doping site was essential for tuning the ORR catalytic activity. N1 doping was shown to more effectively promote the ORR than N2 doping. In addition, our research enhances the current understanding of catalytic activity at the molecular level. [ABSTRACT FROM AUTHOR]

Nanjing City Wall in Nanjing, China, an important cultural heritage of the city, has deteriorated owing to factors such as the presence of microorganisms, salt crystallization, exfoliation, and cracks in the bricks and stones. For this research, the present status regarding the deterioration of the Nanjing City Wall was first surveyed, after which we attempted to identify the factors causing the deterioration. Herein, a simulation model expressing the infiltration of rainwater into the city wall is proposed, and based on the simulation results, the influence of rainwater on the deterioration of the wall is examined. The simulation results showed that the rainwater increases the moisture content of the inside bricks and plaster only very slowly. [ABSTRACT FROM AUTHOR]

Development of detection platforms having portable, easy-to-use, and cost-effective designs is essential for environmental monitoring as well as food safety inspection. Herein, we proposed a smartphone-based handheld sensing strategy integrated with nitrogen-doped carbon dots (NCDs) test strip by employing three-dimensional (3D) printing technology for visual detection of Hg2+. Using this handheld detection platform, the FL color of test strips varied from red to purple with the increase of Hg2+ concentration. A great linear response between the R/B value and Hg2+ concentration in the range of 0 μM− 125 μM was shown, with a detection limit of 0.024 μM. Further, the constructed platform was applied for quantitative detection of Hg2+ in real water samples. Interestingly, as-prepared NCDs allowed the monitoring of Hg2+ with the dual-signal ratiometric model. Finally, the NCDs were used to detect Hg2+ in biological systems with satisfactory results. This work will contribute to the new strategy to design easy-to-use and user-friendly devices for on-site quantitation of targets. • On-site detection integrates nitrogen-doped carbon dots (NCDs) test strip, smartphone and 3D-printed accessory. • Handheld sensing platform was applied for on-site detection of Hg2+ in real water samples. • As-prepared NCDs can be developed as an optical dual-mode probe for ratiometric detection of Hg2+. • The NCDs can be used to detect Hg2+ in living cells and zebrafish. [ABSTRACT FROM AUTHOR]

We systematically investigated the tuning of the reduction potentials ( E 0 ) for the first row transition metal (M = Cr, Mn, Fe, Co, Ni) complexes with the functionalized 1,4,7-Triazacyclononane-N,N',N”-triacetate (TCTA) ligands by means of DFT calculations. To predict reliable E 0 , the modified UB3LYP functional and equilibrium concept between high and low spin states were utilized. The functional groups NH 2 , CN, −F, and NO 2 were attached to the carbon atoms carefully selected by considering the LUMO and steric hindrance. Based on firmed accuracy of DFT calculations, finally we obtained the calculated E 0 for a series of complexes. It was found that electron donating group such as NH 2 will cause a negative shift of E 0 while electron withdrawing groups have the opposite effect. The overall trend of the calculated E 0 s according to ligand modifications were predicted to have the order as −NH 2 < Pristine < −F ≈ −CN < −NO 2 . In addition, optimized geometries, LUMO, vertical electron attachment and energy components constituting E 0 were discussed in detail to assist the further understanding for E 0 s. Consequently, we suggested that 16 complexes can play a role as an electrolyte in aqueous redox flow battery. They can be classified into 5 groups having similar E 0 ranges: Group I (- 0.6 V ∼ − 0.7 V), Group II (around 0.0 V), Group III (around 0.3 V), Group IV (0.6 ∼ 0.8 V) and Group V (1.1 ∼ 1.2 V). Especially, it is expected that [MnL F ] , [MnL CN ] and [NiL NH2 ] can be used as promising catholyte candidates possibly possessing high E 0 s which almost reach to the reduction potential limitation 1.25 V in aqueous redox flow battery. Our systematic approach to tune E 0 can be applied to the design of other complexes via rational ligand modification. [ABSTRACT FROM AUTHOR]

The food additives sodium bisulfite, sodium hypochlorite, citric acid, and ammonium persulfate were evaluated for their effectiveness in degrading aflatoxin in samples of distillers wet grains (DWG) and condensed distillers solubles (CDS) obtained from an industrial ethanol plant. Aqueous food additive solutions, 0.5% by weight, were added to DWG or CDS at the level of 0.5 ml/g of sample, and the materials were heated at 90°C for 1 h. Sodium bisulfite was not effective in degrading aflatoxin in either DWG or CDS. Among the four food additives tested, sodium hypochlorite was the most effective. However, it bleached the substrate and left an off-odor. Citric acid and ammonium persulfate reduced aflatoxin levels by 31 to 51%. Citric acid is the most promising additive for degrading aflatoxin because it has been classified as generally recognized as safe by the U.S. Food and Drug Administration. Aflatoxin reduction was enhanced by increasing the citric acid addition level and prolonging the heating time. Reductions of 65 and 80% in DWG and CDS, respectively, were obtained by the addition of 2.5% (by weight) citric acid and heating at 90°C for 1 h. Aflatoxin levels in DWG and CDS were gradually reduced with prolonged heating at 90°C, even without the addition of food additives. Aflatoxin reductions of 53 and 73% were achieved in DWG and CDS as a result of heating at 90°C for 5 h. [ABSTRACT FROM AUTHOR]

Herein, polyaniline/8-hydroxyquinoline (PAn-HQ) composites with various monomer feed ratios were developed as novel and efficient electrode materials to remove heavy metal ions including Hg(II), Cd(II), Pb(II), Cu(II), Ni(II), and Zn(II) from water resources. Besides detailed structural, morphological, and thermal stability studies, electrochemical properties of fabricated composites were investigated. Compare with PAn with increasing HQ concentration in the initial feed ratio, more resistant, compact, and sticky structures were observed, as well as excellent mechanical and thermal stability of the composites. Due to significant features of the prepared composites, the considerable removal capacity of heavy metal ions has been achieved through electrodeposition technique. Optimum experimental conditions such as HQ concentration, electrodeposition time, ionic strength, pH, and metal ion concentration were considered. Based on our findings, using 0.06 M HQ concentration, remarkable heavy metal ion removal occurs in an aqueous solution with adjusted pH including 1.0 M KNO 3 and 50 mg L−1 initial concentration of metal ion during 24 min electrodeposition. The desorption study by the eluting adsorbent in deionized water at time intervals and adjusted acidic pH values revealed that the initial removal capability of the PAn-HQ composites preserves even after 10 cycles of electrodeposition/desorption. Finally, as-prepared PAn-HQ composites were employed to remove heavy metal ions from a collected real sample from Caspian Sea. The modified PAn-HQ electrodes fabricated via a facile and manageable electrochemical procedure are believed to offer significant adsorption capacity in environmental remediation to remove heavy metal ions. [Display omitted] • PAn-HQ composites were developed for electrochemical removal of heavy metal ions. • PAn-HQ with 0.06 M HQ provided superior R% up to 10 regeneration cycles. • Significant R% was obtained in 24 min, pH of 5, 293 K, and 50 mg L−1 concentration. • Cu(II), Pb(II), Cd(II), Hg(II), Ni(II), and Zn(II) were removed up to about 78%− 97%. • PAn-HQ 3 removed ions of CSW sample simultaneously with 70.26%− 92.01% efficiency. [ABSTRACT FROM AUTHOR]

A new fungal nonribosomal peptide-polyketide hybrid synthase, namely CogA, was discovered by genome mining from fungus Cordyceps gunnii. Its ability to synthesize 4-hydroxyl 2-pyrrolidinone alkaloid (1) via nonenzyme-catalyzed N-1-C-2 closure was confirmed by heterologous expression of it in Aspergillus nidulans. Further engineered biosynthesis of the fluoro-substituted 2-pyrrolidinone alkaloid analogues (4 and 5) has also been achieved in vivo. [ABSTRACT FROM AUTHOR]

Density functional theory calculations were carried out to study how the position of single-atom doping affects the electronic properties of three graphyne models. We found that the position of the dopant (B, N, or O) plays an important role in tuning the electronic structure of graphynes. For α-graphyne, the electronic structure is significantly different for different positions of B and O doping. For β-graphyne, the electronic structure depends remarkably on the doping position for O doping, but not much for B and N doping, whereas for γ-graphyne, it depends on the position for B and O doping, but not for N doping. [ABSTRACT FROM AUTHOR]

Multiband orthogonal frequency division multiplexing (OFDM) subcarrier allocation is a good scheme to fully utilize the available bandwidth under the restriction of dispersion- and chirp-induced power fading in electro-absorption modulator (EAM)-based intensity-modulation-direct-detection (IMDD) OFDM system. In this paper, a modified Tone Reservation (TR) technique combined with subcarrier interleaving is proposed to reduce high peak to average power ratio (PAPR) while minimizing the penalty of subcarrier-to-subcarrier intermixing interference. In the experiment, by incorporating of these two techniques, the receiver sensitivity is improved by about 1.8 dB when a 20 Gbps OFDM signal transmitted along 100 km long single mode fiber in an EAM-based multiband IMDD–OFDM system. [ABSTRACT FROM AUTHOR]

The reaction mechanism for CO 2 absorption in amine solvent was investigated by theoretical analysis. The reactants were CO 2 and six amines, and the reactions were designed with or without additional water or amine molecule. These molecules increase the interaction between reactants and withdraw a proton from amino group of amine. From the additional amine model that shows lowest activation energy, zwitterionic and termolecular mechanisms seem to be suitable for CO 2 capturing reaction in amine solvents. Moreover, the additional amine model can be applied to understand the enhancement effect of CO 2 absorption in blended amine solvents. We report a new attempt that describes reaction mechanism in blended amine solvent by applying additional amine base. The results of CO 2 capture ability were analogous to experimental observation. Comparing our results and previous QM/MM and ab initio MD calculations, it was found that the QM treatment including the reactants and surrounding water molecules would be very critical and the QM region should be properly selected large enough in QM/MM. [ABSTRACT FROM AUTHOR]

In order to investigate the effect of thermal expansion on the ball screw feed drive system of a precision boring machine tool, theoretical modeling of and experimental study on thermally induced error along with heat generation characteristics are focused in this paper. A series of thermal experiments are conducted on the machine tool to measure and collect the thermodynamic data with the feed drive system operating at different speeds. Based on the heat generation and transfer analysis of ball screw system, thermal expansion of screw shaft in the axial direction is modeled mathematically. Relationships between the thermal error and axial elongation are established to characterize the thermal error distribution considering the thermal expansion coefficient as a temperature-variant parameter. It turns out that the thermal error varies with different working positions through the ball screw length and working time nonlinearly, and there definitely exists certain transform from the thermal expansion to the thermal error obtained by measurement. In addition, regression analysis is employed to carry out the theoretical modeling of thermal error with the temperature data of the critical heat generation points. The relations between temperature rise and thermal error are formulated directly while taking the thermal expansion as an implicit variable. Experiments under a different condition are preformed and the proposed methods for thermal error modeling prove to be effective and accurate enough to be used in the machining process as well. [ABSTRACT FROM AUTHOR]

TNFα-targeting therapy with the use of the drugs Etanercept, Infliximab, and Adalimumab is used in the clinical treatment of various inflammatory and immune diseases. Although all of these reagents function to disrupt the interaction between TNFα and its receptors, clinical investigations showed the advantages of Adalimumab treatment compared with Etanercept and Infliximab. However, the underlying molecular mechanism of action of Adalimumab remains unclear. In our previous work, we presented structural data on how Infliximab binds with the E-F loop of TNFα and functions as a TNFα receptor-binding blocker. To further elucidate the variations between TNFα inhibitors, we solved the crystal structure of TNFα in complex with Adalimumab Fab. The structural observation and the mutagenesis analysis provided direct evidence for identifying the Adalimumab epitope on TNFα and revealed the mechanism of Adalimumab inhibition of TNFα by occupying the TNFα receptor-binding site. The larger antigen-antibody interface in TNFα Adalimumab also provided information at a molecular level for further understanding the clinical advantages of Adalimumab therapy compared with Infliximab. [ABSTRACT FROM AUTHOR]

A process-based crop growth model (Vegetation Interface Processes (VIP) model) is used to estimate crop yield with remote sensing over the North China Plain. Spatial pattern of the key parameter—maximum catalytic capacity of Rubisco (V cmax) for assimilation is retrieved from Normalized Difference of Vegetation Index (NDVI) from Terra-MODIS and statistical yield records. The regional simulation shows that the agreements between the simulated winter wheat yields and census data at county-level are quite well with R 2 being 0.41–0.50 during 2001–2005. Spatial variability of photosynthetic capacity and yield in irrigated regions depend greatly on nitrogen input. Due to the heavy soil salinity, the photosynthetic capacity and yield in coastal region is less than 50μmolCm−2 s−1 and 3000kgha−1, respectively, which are much lower than that in non-salinized region, 84.5μmolCm−2 s−1 and 5700kgha−1. The predicted yield for irrigated wheat ranges from 4000 to 7800kgha−1, which is significantly larger than that of rainfed, 1500–3000kgha−1. According to the path coefficient analysis, nitrogen significantly affects yield, by which water exerts noticeably indirect influences on yield. The effect of water on yield is regulated, to a certain extent, by crop photosynthetic capacity and nitrogen application. It is believed that photosynthetic parameters retrieved from remote sensing are reliable for regional production prediction with a process-based model. [Copyright &y& Elsevier]

Background & Aims: X-linked inhibitor of apoptosis protein (XIAP)-associated factor 1 (XAF1) antagonizes the anti-caspase activity of XIAP. XAF1 messenger RNA is present in normal tissues but undetectable in various cancers and thus poses a potential tumor suppressor gene. The aim of this study was to examine the novel pattern of methylation of XAF1 in gastric and colon cancers and locate the important CpG sites for transcriptional regulation and tumor progression. Methods: XAF1 expression was detected by reverse-transcription polymerase chain reaction (PCR) and Western blot analysis. Four different fragments around the transcription start site of XAF1 were cloned and examined putative promoter activities by luciferase reporter assay. Each CpG site in fragment F291 was mutated by site-directed mutagenesis technique, and the change of promoter activity of this fragment was detected by luciferase reporter assay. Methylation status of XAF1 was determined by methylation-specific PCR (MSP) and bisulfite DNA sequencing PCR analysis. Results: Down-regulation of XAF1 in association with hypermethylation was detected in 3 of 4 human gastric cancer cell lines and 6 of 8 colon cancer cell lines. Of the 4 promoter fragments, F291 showed the highest promoter activity, which could be down-regulated obviously by the mutation of particular CpG sites. Moreover, aberrant hypermethylation of these important CpG sites was strongly associated with the development of gastric and colon cancers. Conclusions: A cluster of methylated CpG sites instead of CpG islands located in the promoter area resulted in gene silencing of XAF1, and CpGs at −2nd, −1st, and +3rd positions are functionally more important in its transcriptional regulation. [Copyright &y& Elsevier]

Three widely used methods to calculate the response functions for NaI(Tl) detectors were investigated. The methods were Berger–Seltzer''s method (Nucl. Instrum. Methods 104 (1972) 317), general Monte Carlo (MC) programs, such as EGS4 (The EGS4 code system, Stanford Linear Accelerator Center, 1985) and MCNP4B (MCNP—a general Monte Carlo N-particle transport code, Los Alamos National Laboratory Report, LA-12625-M, 1997), and special MC programs. The pulse height spectra in a 3″×3″ NaI(Tl) detector due to several gamma-ray sources have been measured to verify the calculated results of these methods. The energies of the sources ranged from 0.4118 to 7.11 MeV. The spectra generated by Berger–Seltzer''s method and the general MC programs did not agree well with the experimental data. PETRANS 1.0, the special MC program developed in house, was fairly accurate since it also considered the scintillation efficiency and the single escape peak shift. [Copyright &y& Elsevier]

• Abnormal synaptic plasticity and synaptic homeostasis imbalance in depression. • Aberrant presynaptic SNARE-mediated vesicle release affects synaptic transmission. • Postsynaptic related pathways response to synaptic transmission regulates depression. Depressive disorder is the leading cause of disability worldwide, yet the mechanisms underlying depression are not fully understood. Vesicle release is essential for synaptic neurotransmission, the abnormalities of vesicle release and synaptic plasticity are associated with various neuropsychiatric disorders. Neural circuits are ensembles of interconnected neurons that collectively perform specific functions. To some extent, depression may be caused by a disruption in the structural and functional connections of the neural circuits underlying emotion regulation. In this review, we summarized the role of abnormalities of vesicle release and synaptic transmission, as well as the related regulatory molecules and signal pathways in the regulation of depression. [ABSTRACT FROM AUTHOR]

• Gravity center of walking human body follows trigonometric function approximately. • Backpack load based energy harvester can collect energy from human walking. • Walking speed and load weight determines mechanical energy available for recovery. • Initial oil pressure of storage device is critical to efficient energy harvesting. • Hydraulic energy conversion outstrips electricity in power density and storage. Considerable energy can be harvested from human motions, and energy generated by human walking induced backpack load motion is capable of powering mechatronic systems to reduce energy consumption effectively. This paper mainly deals with the design and performance analysis of the energy recovery system with backpack load based on fluid power transmission technique. The kinematics modeling of the displacement of the gravity center of human body during walking was conducted to describe the generation of mechanical energy within the human gait cycle. Combined with the experimental measurement of gait characteristics, the displacement of cyclical motion of the gravity center was obtained. The energy recovery mechanism was designed making use of the vibration excitation of the backpack load motion to directly convert the human walking induced mechanical energy into hydraulic energy and achieve energy storage with accumulator instantaneously. Through numerical simulation and experimental verification, the energy harvesting results under different walking speeds and backpack loads are analyzed. It is shown that the average output power of the recovery mechanism goes over 6 W at a walking speed of 1.53 m/s with a backpack load of 15 kg, and the captured energy can be increased with the higher speed and larger load. The characteristics of accumulator is critical to achieve continuous energy conversion with increase of walking time. The comparison indicated that the output power and power density of the system proposed in this paper is superior to those based on electric generation, which provided potential solution for energy saving of the hydraulic exoskeleton. [ABSTRACT FROM AUTHOR]

• Hydration and mechanical properties of CSP-CSA system are studied up to 90 days. • CSP can promote the formation of AFt and inhibit the formation of AFm. • The conversion from Hc to Mc does not happen in CSP-CSA binary system. • CSP can accelerate the carbonation of AFt. • CSP can optimize the pore structure of the hardened cement paste in the long term. Recently, the studies on the application of coral reef debris to construction attracted wide attention and interest of researchers, especially in China. Coral reef debris and its powder can be used as fine aggregate and mineral admixture in concrete, respectively. The main component of coral reef debris is calcium carbonate (CaCO 3), up to 90%. In our previous research, the effects of coral sand powder on the hydration behavior and mechanical properties of Portland cement are well investigated. It is well known that calcium sulfoaluminate cement, with low production energy, reduced CO 2 emissions, fast bonding and rapid strength development, etc. has been used for decades in concrete. This paper will give a detailed fundamental research on the hydration kinetics, microstructure development and mechanical properties of the coral sand powder-calcium sulfoaluminate cement binary system up to 90 days of curing. Isothermal calorimetry test, X-ray diffraction analysis, thermogravimetric analysis, mercury intrusion porosimetry and compressive strength tests are used to evaluate the properties of the calcium sulfoaluminate cement incorporated with different contents of coral sand powder (5%, 15% and 25%). The obtained results show that coral sand powder reacts with ye'elimite to generate hemicarboaluminate. Coral sand powder optimizes the pore structure of calcium sulfoaluminate cement at long time curing. [ABSTRACT FROM AUTHOR]

• Hippocampal HDAC5 regulates histone H4 acetylation and stress susceptibility. • Knockdown of the HDAC5 reverses CSDS-induced depression susceptibility. • HDAC5 overexpression promotes depression susceptibility in microdefeat stress mice. Chronic stress leads to social avoidance and anhedonia in susceptible individuals, a phenomenon that has been observed in both human and animal models. Nevertheless, the underlying molecular mechanisms underpinning stress susceptibility and resilience remain largely unclear. There is growing evidence that epigenetic histone deacetylase (HDAC) mediated histone acetylation is involved in the modulation of depressive-related behaviors. We hypothesized that histone deacetylase 5 (HDAC5), which is associated with stress-related behaviors and antidepressant response, may play a vital role in the susceptibility to chronic stress. In the current study, we detected the levels of HDAC5 and acetylation of histone 4 (H4) in the hippocampus subsequent to chronic social defeat stress (CSDS) in C57BL/6J mice. We found that CSDS induces a notable increase in HDAC5 expression, concomitant with a reduction in the acetylation of histone H4 at lysine 12 (H4K12) in the hippocampus of susceptible mice. Meanwhile, intrahippocampal infusion of HDAC5 shRNA or HDAC inhibitor suberoylanilide hydroxamic acid (SAHA) both reversed the depression susceptibility in susceptible mice that subjected to CSDS. Furthermore, HDAC5 overexpression was sufficient to induce depression susceptibility following microdefeat stress, accompanied by a significant reduction in H4K12 level within the hippocampus of mice. Additionally, the Morris water maze (MWM) results indicated that neither CSDS nor HDAC5 exerted significant effects on spatial memory function in mice. Taken together, these investigations indicated that HDAC5-modulated histone acetylation is implicated in regulating the depression susceptibility, and may be serve as potential preventive targets for susceptible individuals. [ABSTRACT FROM AUTHOR]

• Force interactions between foot and ground within a gait cycle are changing in a dynamic manner. • Capturing the vertical component of force and motion generated by foot can maximize the energy harvested from human walking. • Energy induced by footstep motion can be converted into hydraulic energy directly and stored simultaneously. • Hydraulic energy recovery system is superior in power density and storage to those aimed at generating electricity. Human walking induces a lot of mechanical energy available for harvesting. It is promising to use such energy to reduce the energy supply of wearable electronics and robotic equipment such as exoskeleton. This paper mainly deals with the design and performance analysis of the energy recovery system based on fluid power transmission principle. Firstly, modeling and simulation of single foot walking motion were carried out to investigate the human walking dynamics to explore the variation of energy produced by human walking within a gait cycle. Together with gait characteristics measurement, the foot-ground interaction force in the horizontal and vertical directions is obtained. Then, the energy recovery system based on the working principle of volumetric pump was designed to convert the human walking induced mechanical energy into hydraulic energy directly and achieve energy storage with accumulator in the meantime. The energy recovery results obtained under different conditions of walking speed and load carrying are considered by numerical simulation and experimental verification. It is shown that the output power in average of the recovery mechanism by single foot walking at 5.56 km/h is around 3.2 W, and the captured power can be increased with higher precharge pressure of accumulator. Comparisons indicate that power and its density of the system proposed in this paper are far greater than that achieved by electric generation, providing a potential solution for hydraulically actuated walking mechatronic systems. [ABSTRACT FROM AUTHOR]

Abstract Amyloid-beta protein (Aβ) accumulation in the brain, which is influenced by several factors, is a hallmark of Alzheimer's disease (AD). Despite the important role of histidine in stabilizing the fibrillar structure of the Aβ peptide at neutral pH, the effect of histidine tautomerism on Aβ peptide aggregation is still largely unknown. Histidine is in equilibrium between δ and ε tautomers and there are three histidine residues (H6, H13, and H14) in the Aβ(1–40) peptide. We performed molecular dynamics simulation on (δδδ) and (εεε) histidine tautomers with different initial homodimeric configurations to elucidate structural and aggregation features. Results indicate that (εεε) homodimers have very low propensity or almost no tendency to form β-sheets, whereas (δδδ) dimers predominantly form β-sheets due to interactions between central hydrophobic core (CHC) residues and C-terminal residues. β-sheet formation occurred in the same regions of each dimer chain at the CHC and C-/N- terminals for different configurations of (δδδ). These results suggest that (δδδ) has an important role in AD progression. Our study provides deeper insight into the effect of tautomerism of histidine residues in Aβ(1–40) on amyloid aggregation. Graphical abstract Unlabelled Image Highlights • (εεε) tautomers show low propensity to form β-sheets during homodimerization. • (δδδ) tautomers show high β-sheets amount during homodimerization. • (δδδ) tautomers may play more important role than (εεε) in Alzheimer. [ABSTRACT FROM AUTHOR]