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Background: The aim of this retrospective matched‐paired cohort study was to clarify the effectiveness of preserving the vagus nerve in totally laparoscopic radical distal gastrectomy (TLDG). Methods: One hundred eighty-three patients with gastric cancer who underwent TLDG between February 2020 and March 2022 were included and followed up. Sixty-one patients with preservation of the vagal nerve (VPG) in the same period were matched (1:2) to conventional sacrificed (CG) cases for demographics, tumor characteristics, and tumor node metastasis stage. The evaluated variables included intraoperative and postoperative indices, symptoms, nutritional status, and gallstone formation at 1 year after gastrectomy between the two groups. Results: Although the operation time was significantly increased in the VPG compared with the CG (198.0 ± 35.2 vs. 176.2 ± 35.2 min, P < 0.001), the mean time of gas passage in the VPG was significantly lower than that in the CG (68.1 ± 21.7 h vs. 75.4 ± 22.6 h, P = 0.038). The overall postoperative complication rate was similar between the two groups (P = 0.794). There was no statistically significant difference between the two groups hospital stay, total number of harvested lymph nodes, and mean number of examined lymph nodes at each station. During follow-up, the morbidity of gallstones or cholecystitis (8.2% vs. 20.5%, P = 0.036), chronic diarrhea (3.3% vs. 14.8%, P = 0.022), and constipation (4.9% vs. 16.4%, P = 0.032) were significantly lower in the VPG than in the CG in this study. Moreover, injury to the vagus nerve was found to be an independent risk factor for gallstone formation or cholecystitis and chronic diarrhea in univariate analysis and multivariate analysis. Conclusion: The vagus nerve plays an imperative role in gastrointestinal motility, and hepatic and celiac branch preservation mainly exerts efficacy and safety in patients who undergo TLDG. [ABSTRACT FROM AUTHOR]

The pandemic of Gompertz virus disease remains a pressing issue in agricultural production. Moreover, the dynamics of various infectious diseases is usually investigated by the method of mathematical modelling. A new mathematical model for dynamics on Gompertz virus disease impulsive system is proposed and analyzed in this paper. We prove the dynamic characteristics about the permanence and globally exponential stability of Gompertz virus disease model. Moreover, we also give the sufficient condition that one positive solution which satisfies E (t) ≥ q 2 if R 1 ∗ > 1 exists. Eventually, numerical simulations are utilized to validate the validity of the theoretically analyzed conclusion in this paper. [ABSTRACT FROM AUTHOR]

The prognostic significance of neural invasion (NI) in gastric cancer (GC) has not been established. This study is to investigate the characteristic and prognostic value of NI in GC. 592 patients who had undergone gastrectomy for GC were retrospectively analyzed. NI was defined when cancer cells infiltrated into the perineurium or neural fascicles by hematoxylin and eosin staining of surgical specimens. NI and the other clinical factors were analyzed. NI was detected in 270 of the 592 patients. NI was associated with tumor size, site, depth of invasion, lymph node metastasis, TNM stage, D dissection, tumor differentiation, Lauren classification, and blood vessel invasion. NI was associated with the overall survival. Multivariate analysis indicated that NI was not an independent prognostic factor for total patients, while NI independently predicted prognosis for age < 60 and lymph node metastasis negative patients by subgroup analysis. Concomitant existence of NI with tumor size ≥3cm, TNM stage III, or diffused Lauren classification independently predicted prognosis. The frequency of NI is high in GC patients and increases with disease progression. NI is related to poor survival in GC patients who underwent curative gastrectomy and provides independent prognostic value for young and lymph node metastasis negative patients. [ABSTRACT FROM AUTHOR]

Surface hopping (SH) is a popular mixed quantum-classical method for modeling nonadiabatic excited state processes in molecules and condensed phase materials. The method is simple, efficient, and easy to implement, but the use of classical and independent nuclear trajectories introduces an overcoherence in the electronic density matrix which, if ignored, often leads to spurious results, such as overestimated reaction rates. Several methods have been proposed to incorporate decoherence into SH simulations, but a lack of insightful benchmarks makes their relative accuracy unknown. Herein, we run numerical simulations of common coherence-corrected SH methods including Truhlar's decay-of-mixing (DOM) and Subotnik's augmented SH using a Donor-bridge-Acceptor (DbA) model system. Numerical simulations are carried out in the superexchange regime, where charge transfer proceeds from a donor to an acceptor as a result of donor-bridge and bridge-acceptor couplings. The computed donor-to-acceptor reaction rates are compared to the reference Marcus theory results. For the DbA model under consideration, augmented SH recovers Marcus theory with quantitative accuracy, whereas DOM is only qualitatively accurate depending on whether predefined parameters in the decoherence rate are chosen wisely. We propose a general method for parameterizing the decoherence rate in the DOM method, which improves the method's reaction rates and presumably increases its transferability. Overall, the decoherence method of choice must be chosen with great care and this work provides insight using an exactly solvable model. [ABSTRACT FROM AUTHOR]

We present a new interpretation of the decoherence correction in surface hopping by examining the inconsistency of the traditional time-dependent Schrödinger equation and propose an elegant decoherence correction algorithm to deal with wave packet branching. In contrast to the widely used approaches based on decoherence rates, our branching corrected surface hopping (BCSH) resets the wavefunction directly after wave packet branching is identified through prediction of trajectory reflection. The appealing simplicity and reliability of BCSH are demonstrated in a series of widely studied one-dimensional and two-dimensional scattering models using exact quantum solutions and existing surface hopping approaches as references. The BCSH approach exhibits a high performance in all investigated systems, showing good potential for applications in general nonadiabatic dynamics simulations. [ABSTRACT FROM AUTHOR]

We present a semiclassical Moyal dynamics (SMD) method based on the phase space formulation of quantum dynamics. In contrast to the quantized Hamiltonian dynamics approach by Prezhdo et al. using the Heisenberg equation of motion, SMD adopts the Moyal equation of motion to derive the time evolution of expectation values and uses an auxiliary phase space distribution technique to systematically terminate the coupled equations of motion. Thereby, tedious derivation of commutators is essentially not required, and semiclassical dynamics of arbitrary orders can be realized. The appealing simplicity, flexibility, and reliability of SMD are demonstrated in three representative model systems with strong quantum effects. [ABSTRACT FROM AUTHOR]

Based on augmented Tikhonov regularization (ATR) method and matrix perturbation method, a new computational inverse method is proposed to reconstruct impact loads acting on composite laminated cylindrical shell with random characteristics. Firstly, the stability and effectiveness of augmented Tikhonov regularization method are investigated in solving deterministic inverse problem about impact load identification of composite laminated cylindrical shell structure. Secondly, exploiting the matrix perturbation method, the impact load identification of composite laminated cylindrical shell structure with uncertain factors is transformed into a range of traditional impact load identification with deterministic structure. Lastly, using the knowledge of statistical theory, the statistical features of identified impact force are also analyzed. Numerical simulations validate that the proposed algorithm in this paper successfully solves the impact load identification of composite laminated cylindrical shell with and without random characteristics. [ABSTRACT FROM AUTHOR]

Due to the lack of typical clinical manifestations, the incomplete Kawasaki disease (KD) is easily misdiagnosed and missed. The sudden death risk in incomplete KD cases is similar to typical KD. In this study, we report a case of a 1-year-old boy who died suddenly without any warning after incomplete KD. The boy was admitted due to fever and a cough, with preliminary diagnosis of acute severe bronchial pneumonia, but no typical KD characteristics. After antibiotics and supportive treatment, the condition worsened. Finally, the boy died after the ineffective rescue. The pathology revealed that the boy suffered from incomplete KD. From this case, we experience that, when infants or children have a long-lasting fever, the possibility of KD should not be ignored. In addition, when managing such patients, the frequency of heart ultrasound should be increased as appropriate. [ABSTRACT FROM AUTHOR]

The performance of the mean field theory to account for charge transfer rate in molecular dimers and charge transport mobility in molecular stacks with small intermolecular electronic coupling and large local electron-phonon coupling (i.e., in the hopping regime) is carefully investigated against various other approaches. Using Marcus formula as a reference, it is found that mean field theory with system-bath interaction and surface hopping approaches yield fully consistent charge transfer rates in dimers. However, in contrast to the dimer case, incorporating system-bath interaction in the mean field approach results in a completely wrong temperature dependence of charge carrier mobility in larger aggregates. Although the mean field simulation starting from the relaxed geometry of a charged molecule and neglecting system-bath interaction can reproduce thermally activated transport, it is not able to characterize properly the role of additional nonlocal electron-phonon couplings. Our study reveals that the mean field theory must be used with caution when studying charge transport in the hopping regime of organic semiconductors, where the surface hopping approach is generally superior. [ABSTRACT FROM AUTHOR]

Dynamic forces are very important boundary conditions in practical engineering applications, such as structural strength analysis, health monitoring and fault diagnosis, and vibration isolation. Moreover, there are many applications in which we have found it very difficult to directly obtain the expected dynamic load which acts on a structure. Some traditional indirect inverse analysis techniques are developed for load identification by measured responses. These inverse problems about load identification mentioned above are complex and inherently ill-posed, while regularization methods can deal with this kind of problem. However, most of regularization methods are only limited to solve the pure mathematical numerical examples without application to practical engineering problems, and they should be improved to exclude jamming of noises in engineering. In order to solve these problems, a new regularization method is presented in this article to investigate the minimum of this minimization problem, and applied to reconstructing multi-source dynamic loads on the frame structure of hydrogenerator by its steady-state responses. Numerical simulations of the inverse analysis show that the proposed method is more effective and accurate than the famous Tikhonov regularization method. The proposed regularization method in this article is powerful in solving the dyanmic load identification problems. [ABSTRACT FROM AUTHOR]

Laparoscopic proximal gastrectomy (LPG) with double-tract reconstruction (DTR) is performed as a function-preserving surgery for patients with adenocarcinoma of esophagogastric junction. However, whether LPG with DTR has postoperative advantages over laparoscopic total gastrectomy (LTG) is debatable. To evaluate benefits of LPG with DTR, we compared short-term surgical outcomes between LPG with DTR and LTG for adenocarcinoma of esophagogastric junction (AEG). Twelve patients who underwent LPG with DTR for AEG between February 2016 and August 2017 were included. Twenty-four patients who underwent LTG in the same period were matched to LPG with DTR cases for demographics, comorbidities, tumor characteristics, and tumor node metastasis stage. Short-term surgical outcomes were compared between the two groups. Demographics of the LPG with DTR group and LTG group were comparable. The number of harvested lymph nodes in the LPG with DTR group was less than that in the LTG group, and the amount of estimated blood loss, the operative time, the days of gas-passing, start of diet, postoperative hospital stay were not significantly different between the groups. Furthermore, the postoperative reflux symptom in the LPG with DTR group was not significantly different with that in the LTG group. However, the increasing percentages of the serum albumin, total protein, and hemoglobin levels in the LPG with DTR group were significantly higher than those in the LTG group. This study reveals that LPG with DTR may be a valuable procedure for the treatment of AEG because it has the advantages over LTG in terms of postoperative serum albumin, total protein, and hemoglobin. [ABSTRACT FROM AUTHOR]

The electron-phonon coupling is critical in determining the intrinsic charge carrier and exciton transport properties in organic materials. In this study, we consider a Su-Schrieffer-Heeger (SSH) model for molecular crystals, and perform numerical benchmark studies for different strategies of simulating the mixed quantum-classical dynamics. These methods, which differ in the selection of initial conditions and the representation used to solve the time evolution of the quantum carriers, are shown to yield similar equilibrium diffusion properties. A hybrid approach combining molecular dynamics simulations of nuclear motion and quantum-chemical calculations of the electronic Hamiltonian at each geometric configuration appears as an attractive strategy to model charge dynamics in large size systems 'on the fly,' yet it relies on the assumption that the quantum carriers do not impact the nuclear dynamics. We find that such an approximation systematically results in overestimated charge-carrier mobilities, with the associated error being negligible when the room-temperature mobility exceeds ∼4.8 cm2/Vs (∼0.14 cm2/Vs) in one-dimensional (two-dimensional) crystals. [ABSTRACT FROM AUTHOR]

Semiclassical Marcus electron transfer theory is often employed to investigate the charge transport properties of organic semiconductors. However, quite often the electronic couplings vary several orders of magnitude in organic crystals, which goes beyond the application scope of semiclassical Marcus theory with the first-order perturbative nature. In this work, we employ a generalized nonadiabatic transition state theory (GNTST) [Zhao et al., J. Phys. Chem. A 110, 8204 (2004)], which can evaluate the charge transfer rates from weak to strong couplings, to study charge transport properties in prototypical organic semiconductors: quaterthiophene and sexithiophene single crystals. By comparing with GNTST results, we find that the semiclassical Marcus theory is valid for the case of the coupling <10 meV for quaterthiophene and <5 meV for sexithiophene. It is shown that the present approach can be applied to design organic semiconductors with general electronic coupling terms. Taking oligothiophenes as examples, we find that our GNTST-calculated hole mobility is about three times as large as that from the semiclassical Marcus theory. The difference arises from the quantum nuclear tunneling and the nonperturbative effects. [ABSTRACT FROM AUTHOR]

Objectives: Gastric cancer (GC) is one of the most common cancers in the world, causing a large number of deaths every year. The Slit‐Robo signalling pathway, initially discovered for its critical role in neuronal guidance, has recently been shown to modulate tumour invasion and metastasis in several human cancers. However, the role of Slit‐Robo signalling and the molecular mechanisms underlying its role in the pathogenesis of gastric cancer remains to be elucidated. Materials and methods: Slit2, Robo1 and USP33 expressions were analysed in datasets obtained from the Oncomine database and measured in human gastric cancer specimens. The function of Slit2‐Robo1‐USP33 signalling on gastric cancer cells migration and epithelial‐mesenchymal transition (EMT) was studied both in vitro and in vivo. The mechanism of the interaction between Robo1 and USP33 was explored by co‐IP and ubiquitination protein analysis. Results: The mRNA and protein levels of Slit2 and Robo1 are lower in GC tissues relative to those in adjacent healthy tissues. Importantly, Slit2 inhibits GC cell migration and suppresses EMT process in a Robo‐dependent manner. The inhibitory function of Slit2‐Robo1 is mediated by ubiquitin‐specific protease 33 (USP33) via deubiquitinating and stabilizing Robo1. USP33 expression is decreased in GC tissues, and reduced USP33 level is correlated with poor patient survival. Conclusions: Our study reveals the inhibitory function of Slit‐Robo signalling in GC and uncovers a role of USP33 in suppressing cancer cell migration and EMT by enhancing Slit2‐Robo1 signalling. USP33 represents a feasible choice as a prognostic biomarker for GC. [ABSTRACT FROM AUTHOR]

Highlights • Solubilities in the mixed system of (NaF-Na 2 CO 3 -H 2 O) and (NaF-Na 2 CO 3 -NaHCO 3 -H 2 O) were determined at 308.15 K and 323.15 K. • The solubility products of double salt NaF·Na 2 SO 4 and mixing parameters in Na-F-SO 4 -H 2 O system were obtained. • A Pitzer-based solid-liquid equilibrium model in Na-F-Cl-SO 4 -CO 3 -HCO 3 -H 2 O system was developed up to 363.15 K. • Model calculations are in good agreement with the reference data. Abstract Fluoride is highly related to human health. Thermodynamic equilibrium models can used as be powerful predictive and interpretive tools to evaluate its potential hazards. A few works have ever been conducted to deal with fluoride involved aqueous solutions. However, bicarbonate and sulfate, which have a positive relationship with the concentration of fluoride in aqueous solutions, have not been evaluated. In this work, the solubilities in the NaF-Na 2 CO 3 -H 2 O system and the NaF-Na 2 CO 3 -NaHCO 3 -H 2 O system were determined with the isothermal dissolution method at (308.15 and 323.15) K and atmosphere pressure. Using this set of experimental data and those from the literature, a thermodynamic equilibrium model in the mixed system Na-F-CO 3 -HCO 3 -H 2 O was developed based on the Pitzer specific interaction model. The model gave very good agreement with the experimental solubility data. For the Na-F-SO 4 -H 2 O system, the solubility products of the double salt NaF·Na 2 SO 4 and ternary Pitzer parameters were determined from experimental data available in the literature. Combining the parameters evaluated in this work and those from previous literature, a solid-liquid equilibrium model was developed for the Na-F-Cl-SO 4 -CO 3 -HCO 3 -H 2 O system at temperatures up to 363.15 K. The model was validated by comparing solubility predictions with experimental data given in literature, and those were not used in the parameterization process. [ABSTRACT FROM AUTHOR]

An efficient near-infrared (NIR) down-conversion in Ce 3+ -Yb 3+ codoped oxyfluoride glass ceramics (GC) have been investigated with different annealing temperature. With an 430 nm (Ce 3+ : 4f → 5d) excitation, the NIR emission at around 1000 nm (Yb 3+ : 2 F 5/2  →  2 F 7/2 ) was obtained which confirming efficient energy transfer between Ce 3+ ions and Yb 3+ ions. Subsequently, the possible mechanism of energy transfer was investigated and discussed. Finally, the energy conversion efficiency was measured which the Si solar cell covered by Ce 3+ -Yb 3+ codoped oxyfluoride GC. The maximum efficiency which increased by 0.3% indicated that the Ce 3+ /Yb 3+ sample had the potential applications for solar cells. [ABSTRACT FROM AUTHOR]

For the dynamic load identification for stochastic structures, ill-posedness and randomness are main causes that lead to instability and low accuracy. Monte-Carlo simulation (MCS) method is a robust and effective random simulation technique for the dynamic load identification problems of stochastic structures. However, it needs large computational cost and is also inefficient for practical engineering applications because of the requirement of a large quantity of samples. In order to improve its computational efficiency, this paper proposes a novel computational algorithm for the dynamic load identification of stochastic structures. First, the newly developed algorithm transforms dynamic load identification problems for stochastic structures into equivalent deterministic dynamic load identification problems. Second, a new regularization method is proposed to realize the deterministic dynamic load identification. Third, the assessments of the statistics of identified loads are obtained based on statistical theory. Finally, the stability and robustness of the proposed algorithm are well validated by two engineering examples. It is demonstrated that the newly developed regularization method outperforms the traditional Tikhonov regularization method in computational accuracy. Moreover, the newly proposed algorithm can significantly improve the computational efficiency of MCS and is very stable and effective in solving the dynamic load identification for stochastic structures. [ABSTRACT FROM AUTHOR]

We report a surface hopping approach in which the implemented linear vibronic coupling Hamiltonian is constructed and the electronic wavefunction is propagated in the reciprocal space. The parameters of the linear vibronic coupling model, including onsite energies, phonon frequencies, and electron–phonon couplings, are calculated with density-functional theory and density-functional perturbation theory and interpolated in fine sampling points of the Brillouin zone with maximally localized Wannier functions. Using this approach, we studied the relaxation dynamics of the photo-excited hot carrier in a one-dimensional periodic carbon chain. The results show that the completeness of the number of Hilbert space k points and the number of phonon q points plays an important role in the hot carrier relaxation processes. By calculating the relaxation times of hot carriers under different reciprocal space sampling and extrapolating with the stretched–compressed exponential function, the relaxation times of hot electrons and holes in the quasi-continuous energy band are obtained. By considering the feedback effect in the hopping processes and analyzing the time-dependent phonon energy in different normal modes, we found that the long-wave longitudinal optical phonons play a major role in the relaxation dynamics of hot electrons and holes. We, therefore, provided herein an efficient and accurate approach for modeling the photophysical processes in periodic solid-state material systems. [ABSTRACT FROM AUTHOR]

Disordered or even seemingly amorphous, donor–acceptor type, conjugated copolymers with high charge-carrier mobility have emerged as a new class of functional materials, where transport along the conjugated backbone is key. Here, we report on non-adiabatic molecular dynamics simulations of charge-carrier transport along chains of poly (indacenodithiophene-co-benzothiadiazole), within a model Hamiltonian parameterized against first-principles calculations. We predict thermally activated charge transport associated with a slightly twisted ground-state conformation, on par with experimental results. Our results also demonstrate that the energy mismatch between the hole on the donor vs the acceptor units of the copolymer drives localization of the charge carriers and limits the intra-chain charge-carrier mobility. We predict that room-temperature mobility values in excess of 10 cm2 V−1 s−1 can be achieved through proper chemical tuning of the component monomer units. [ABSTRACT FROM AUTHOR]

We synthesize Ce-doped oxyfluoride glass ceramics (GCs) with different melting times employing the conventional melt-quenching method. We investigate the crystal structure and photoluminescence properties of Ce-doped GCs in detail in order to evaluate the effect of melting times on the downshifting properties. The photoluminescence properties revealed that the Ce doped GCs have an intense emission band in the broad region from 480 to 600 nm under 427 nm excitation. We improve the energy-conversion efficiency of a-Si solar cells by 0.41%, from 5.02% to 5.43%, by incorporating the Ce-doped GCs with a melting time of 1.5 h. The above results indicate that Ce-doped GCs can be a promising candidate as downshifting materials for applications in a-Si solar cells. [ABSTRACT FROM AUTHOR]

Composites with good mechanical and tribological properties are in high demand for engineering applications. Toward this aim, the Mo–12Si–8.5B alloy with 2.5–10 wt% ZrB 2 ceramic was prepared. The effects of the ZrB 2 content on the microstructure, mechanical properties, and tribological behavior were thoroughly investigated. The composites exhibited reduced density and enhanced hardness and strength owing to the dispersion strengthening of ZrB 2 particles, thus resulting in improved wear resistance. The frictional properties are highly dependent on the ZrB 2 content and counterpart materials. When coupled with GCr15 steel, it shows much slighter abrasive and adhesive wear; therefore, it presents a more preferable anti-wear performance. The wear rate of the composite with 7.5 wt% ZrB 2 showed a minimum value of 2.71 × 10−7 mm3N−1m−1. [ABSTRACT FROM AUTHOR]

In this paper, we propose an impulsive predator–prey model with communicable disease in the prey species only and investigate its interesting biological dynamics. By the Floquet theory of impulsive differential equation and small amplitude perturbation skills, we have deduced the sufficient conditions for the globally asymptotical stability of the semi-trivial periodic solution and the permanence of the proposed model. We also give the existences of the “infection-free” periodic solution and the “predator-free” solution. Finally, numerical results validate the effectiveness of theoretical analysis for the proposed model in this paper. [ABSTRACT FROM AUTHOR]

In this work, graphene is tried to use to improve the performance of polycrystalline CdZnTe high-energy radiation and photon detectors. A graphene intermediate layer is prepared by spin-coating process on the surface of polycrystalline CdZnTe film, which forms a photoconductive Au/graphene/CdZnTe/FTO structure. XRD, Raman, photoelectric response and other characterisation methods are adopted to investigate the effect of graphene layer on the electrical characteristics and UV photo-response performance of CdZnTe photoconductive structure. It is demonstrated that graphene layer can significantly improve the contact property of Au/CdZnTe structure, and obviously enhance its UV photo-response and the UV sensitivity increased with one order of magnitude. [ABSTRACT FROM AUTHOR]

We report on a first-principle theoretical investigation of the optical absorption and emission spectra of poly(3-hexylthiophene) (P3HT) aggregates by means of a multiscale all-atom hybrid approach, which combines: (i) molecular dynamics simulations of (intrachain) conformational and (interchain) positional disorder, (ii) quantum-chemical calculations of intrachain excited states and excitonic interactions, and (iii) solving of a Frenkel–Holstein model that includes coupling of the electronic excitations to a dominant high-frequency molecular vibration. The modeling work points to the co-existence of ordered nano-aggregates into disordered domains, with the former dominating the emission spectrum while both regions contribute to the absorption spectrum. The measured photoluminescence line shape and the Stokes shift are both reproduced by the theory for aggregates comprising polymer chain with lengths ∼35–40 repeating units. [ABSTRACT FROM AUTHOR]

Since the seminal work of Tully [J. Chem. Phys. 93, 1061 (1990)], two-level scattering models have been extensively adopted as the standard benchmark systems to assess the performance of different trajectory surface hopping methods for nonadiabatic dynamics simulations. Here, we extend the branching and phase corrections to multilevel systems and combine them with both the traditional fewest switches surface hopping (FSSH) and its variant global flux surface hopping (GFSH) algorithms. To get a comprehensive evaluation of the proposed methods, we construct a series of more challenging and diverse three-level and four-level scattering models and use exact quantum solutions as references. Encouragingly, both FSSH and GFSH with the branching and phase corrections produce excellent and nearly identical results in all investigated systems, indicating that the new surface hopping methods are robust to describe multilevel problems and the reliability is insensitive to the definition of self-consistent hopping probabilities in the adiabatic representation. Furthermore, the branching correction is found to be especially important when dealing with strongly repulsive potential energy surfaces, which are common in realistic systems, thus promising for general applications. [ABSTRACT FROM AUTHOR]

Numerical simulation of oil reservoirs is one of the most commonly used methods for reservoir production prediction, but its accuracy is based on accurate geological modeling and high-quality history matching. Therefore, numerical simulation is time-consuming and costly and requires extensive information. Traditional back-propagation neural networks and their improved algorithms are widely used for production prediction, but they are not suitable for time-series prediction problems. Based on variations in oil production, this study proposes a reservoir production prediction model based on a combined convolutional neural network (CNN) and a long short-term memory (LSTM) neural network model optimized by the particle swarm optimization (PSO) algorithm. First, the model extracts important temporal data features through the upper CNN, which is next imported to the lower LSTM network to further extract correlation features in the time dimension; then, it iteratively optimizes the key hyperparameters in the CNN-LSTM model through the PSO algorithm; finally, it uses the trained model for reservoir prediction. Compared with the training results of the LSTM neural network and CNN model, the PSO–CNN-LSTM model has higher prediction accuracy in time-series production prediction. Our proposed hybrid model is a data-driven method and is based on routinely available production data. Quick and accurate production prediction can lead to better informed operational decisions and optimization of recovery and economics. • This study proposes a production prediction model based on CNN-LSTM model optimized by PSO algorithm. • The hybrid CNN-LSTM model can better characterize spatial and temporal correlations than the single CNN or LSTM model.. • The PSO algorithm can speed up the process of obtaining the optimal hyperparameters. • The PSO algorithm can optimize the architecture of any deep-learning model with challenges in the time-series problem. [ABSTRACT FROM AUTHOR]

Polycrystalline CdZnTe thick films with an average grain size of 30 μm and thickness of 270 μm were successfully grown on SnO 2 :F (FTO)-coated glass substrates by close-spaced sublimation method. Electrical properties and UV response of CdZnTe thick films after Br–MeOH etching and ZnCl 2 annealing treatment were investigated. By means of the photo-current measurements, the value of mobility–lifetime ( μτ ) products for CdZnTe films were firstly reported. The results showed that Br–MeOH etching significantly improved UV detection sensitivity of CdZnTe thick films, and made the surface distribution of UV sensitivity more homogeneous. It was also found that a ZnCl 2 annealing process did not improve the electrical properties. [ABSTRACT FROM AUTHOR]

Solar power is the ideal use of solar energy. It is better to adopt tracking mode to track the sun automatically, and the solar receiver can get more solar energy for tracking system lets incident sunlight keep parallel to collector. The auto-tracking modes include program tracking mode, photoelectric tracking mode and hybrid tracking mode. Considering that program tracking mode has accumulative error although it can be all-weather tracking, and photoelectric sensor tracking has better tracking sensitivity and higher tracking precision only in the sunny day, solar auto-tracking system generally adopts hybrid tracking mode which is a combination of program tracking mode and photoelectric sensor tracking mode; for photoelectric sensor tracking mode eliminates accumulated error of program tracking mode, the system can achieve the goal of all-weather high-precision tracking. In this mode, photoelectric tracking mode uses light intensity detection information of photoelectric sensor to adjust the tracking system's position, so the design of photoelectric sensor's structure can directly affect solar auto-tracking system's tracking accuracy and running stability. At present, the most widely used types of photoelectric sensor are baffled type, pyramidal type, tube type, etc. Baffled type photoelectric sensor is vertically arranged on the base; making use of barrier, when there exists the included angle between barrier and incident light, light sensors on both sides will receive different light intensity, and then sun position can be determined. It has lower price and convenient installation with simple structure, but its motor rotates frequently and the system has lower tracking accuracy, for it is easily affected by external lights from different directions. Pyramidal type photoelectric sensor makes full use of cosine principle, and the light exposure to silicon photocell of the pyramid side, is equal to the area multiplied by incident light angle cosine. Even though its accuracy is higher than baffled type's, it is still influenced by environmental astigmatism. Tube type has higher tracking precision than others, but the solar incident angle and the height of the tube are conditioned by each other so that it causes the mutual influence between system's tracking stability and tracking precision. Photoelectric sensor, whose structural design has a great influence on the system's tracking accuracy and operational stability, is the detecting element of photoelectric tracking. In order to solve existing sensors' problems, such as single form, low tracking accuracy, bad stability, this paper designs a kind of photoelectric sensor, which is a combination of pyramidal type photoelectric sensor and box type photoelectric sensor, and can track accurately. The pyramid type photoelectric sensor is outside the box type and roughly tracks, while the box type accurately tracks. The concave-mirror, inside the box type, has reflection effect so that it can effectively reduce the box height of the sensor, and the box type and the pyramid type photoelectric sensor can be disassembled to work alone. LM324 comparator, as the core of the system, controls the motor to drive actuator to track sun in the circuit of the sensor. This paper then builds controller models and simulates by MATLAB/Simulink, and the fuzzy PID (proportional integration differentiation) control can let the tracking system return to steady state under disturbance. This control method can achieve optimal control, which means not only the simulation result is intuitional and believable, but also the method can greatly save the cost. The system can quickly return to steady state even in a case of interference, therefore, it has realized tracking feature without error, and also has proved that the fuzzy PID control method can maintain certain performance of the system, and the system has great robustness. Tracking system has better performance with the fuzzy PID controller. In addition, it is simple and continent with Simulink to establish the model and then simulate, and the simulation results are intuitively credible. Simulink can realize the different systems' real simulation better, and then get better simulation results. [ABSTRACT FROM AUTHOR]

Nonequilibrium processes involving electronic and vibrational degrees of freedom in nanoscale materials are under active experimental investigation. Corresponding theoretical studies are much scarcer. The review starts with the basics of time-dependent density functional theory, recent developments in nonadiabatic molecular dynamics, and the fusion of the two techniques. Ab initio simulations of this kind allow us to directly mimic a great variety of time-resolved experiments performed with pump-probe laser spectroscopies. The focus is on the ultrafast photoinduced charge and exciton dynamics at interfaces formed by two complementary materials. We consider purely inorganic materials, inorganic-organic hybrids, and all organic interfaces, involving bulk semiconductors, metallic and semiconducting nanoclusters, graphene, carbon nanotubes, fullerenes, polymers, molecular crystals, molecules, and solvent. The detailed atomistic insights available from time-domain ab initio studies provide a unique description and a comprehensive understanding of the competition between electron transfer, thermal relaxation, energy transfer, and charge recombination processes. These advances now make it possible to directly guide the development of organic and hybrid solar cells, as well as photocatalytic, electronic, spintronic, and other devices relying on complex interfacial dynamics. [ABSTRACT FROM AUTHOR]

The energy crisis and environmental pollution have become increasingly prominent, therefore human beings have been exploring and making use of new energy resources. Solar energy, a new energy resource that is clean, renewable, economical, universal, etc., has grown fast worldwide. Taking advantage of solar energy can solve the energy shortage, and solar energy has an important effect on our country's future development. Solar power is considered to be one of the most ideal utilizations of solar energy. The solar thermal power generation is widely concerned. Among dish, groove, and tower solar thermal power generation, dish solar thermal power generation has the highest photoelectric conversion efficiency, and it belongs to point collector generation technology, which makes it worth to develop. The ever-changing solar radiation direction and the instability of the solar radiation energy lead to the inaccuracy of tracking systems and lower utilization. When the incident sunlight parallels the solar collector, the conversion efficiency is higher. Tracking mode can greatly improve the solar utilization rate. Research shows that energy receiving rate improves 37.7% when solar thermal power generation uses tracking mode. Accurate sun tracking can greatly improve the receiver's thermal efficiency. Compared to fixed systems, power output of single-axis and dual axis tracking systems can increase 25% and 41% under the same condition. It is clear that an accurate auto-tracking control system can make solar collectors receive more solar radiation energy to improve the solar energy utilization. Although the tracking system is more complex and costs higher than the fixed system, increasing the annual output power can reduce cost effectively. Program tracking mode, which is not affected by the weather, has high adaptability. When the control software calculates the sun's position, inevitably it would have round-off error. Photoelectric tracking mode has higher tracking accuracy because it can automatically track the sun and is seriously influenced by the weather. Auto-tracking mode of the dish solar tracking system commonly uses hybrid tracking that is a combination of program tracking mode and photoelectric tracking mode. Each tracking mode makes up for the other, so as a result, the precision and stability of the tracking system is further improved and guaranteed. The tracking system works outside, therefore it is easily influenced by environmental factors so tracking accuracy and stabilization is lower. In order to improve tracking accuracy of the dish solar auto-tracking system, this paper chose the more precise transmission mechanism to match the system and mainly focuses on the transmission mechanism error of the dish solar tracking system. Based on a working platform of the existing 1 kW dish solar auto-tracking system, this paper designs a kind of transmission mechanism. The azimuth angle uses double worm single worm wheel; two worms work together to drive the worm wheel. The running speed and direction of the worms are the same, and the screw nut transmission mechanism with self-locking function tracks the altitude angle. Second, deduce the driving equation of the altitude angle and azimuth angle. Thenusesa software named ADAMS is used to do the system's simulation. The simulation focuses on spring equinox, summer solstice, autumn equinox, and winter solstice in 2013 in Lanzhou based on kinematics of the tracking transmission mechanism. The analytical result shows that kinematics errors of the tracking transmission mechanism are nearly +0.021°. Compared to the minimum systematic error, which is ±0.20º, the kinematics errors are just 10%. At the same time, the errors of the dish solar auto-tracking system are analyzed. It lays a theoretical foundation of the study to improve the precision of the dish solar auto-tracking system. Transmission mechanism error is only part of the dish solar auto-tracking system's errors; relevant follow-up studies on other errors of the system are ongoing. [ABSTRACT FROM AUTHOR]

In this study, the Indium (In) doped Cd1 -xMn x Te ( xMn=0.1, CdMnTe) crystals with excess Te in the amount of 0 and 1.2 at% were grown by the Bridgman method. The segregation coefficient of In dopants distributions in the CdMnTe crystals with and without excess Te were determined to be 0.08 and 0.11, respectively. The IR transmission microscopy shown that the size of Te inclusions in CdMnTe crystal with excess Te increased to 5-13 μm with the concentrations of (2-3)×105 cm-3. The PL spectra indicated the formation of Te antisite donor and the compensation of Cd vacancies by Te antisites. The Current-Voltage measurements were performed and the resistivity of the CdMnTe crystal with excess Te was in the range of 108-109 Ω·cm, increased by one order as compared to the crystal without excess Te. Under the radiation of 59.5 keV 241Am, The CdMnTe planar detectors fabricated from the crystal with excess Te revealed the energy resolution of 8.4%, however, no energy response is resolved in the CdMnTe detectors without excess Te. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Abstract: An indium-doped detector grade Cd0.9Zn0.1Te crystal was grown by the THM technique from Te-rich solution. The as-grown crystal showed the dark resistivity of (1–3)×1010 Ωcm. Through IR transmission microscopy Te inclusion with regular triangular or circular shapes could be observed, and the size of Te inclusion was around 7μm and the concentration was ∼105 cm−3. The impurity concentrations were greatly reduced for the THM grown CZT, as compared to the Bridgman method grown CZT. A resolution of 8.5% was achieved under the 662keV 137Cs gamma ray radiation at room temperature for the as-grown CZT samples. [Copyright &y& Elsevier]

Abstract: High resistivity (3 × 109 Ω cm) polycrystalline CdZnTe thick films with thickness of 25 μm–150 μm were grown on SnO2: F-coated glass substrates by close-spaced sublimation method. The properties of polycrystalline CdZnTe films were studied by XRD, SEM and EDS, respectively. A CdZnTe film Schottky diode detector was also fabricated and investigated using current–voltage and capacitance–voltage methods. The photo-current density of the device was about 1508.69 nA/mm2 under light illumination (λ = 260 nm), at an applied negative voltage of 15 V. The results showed that polycrystalline CdZnTe thick film was suitable for application in ultraviolet detectors. [Copyright &y& Elsevier]

Abstract: Indium-doped Cd1−x Mn x Te (x=0.2, CdMnTe) crystals were annealed under Cd vapor atmosphere to improve the properties of CdMnTe. The quasichemical equilibrium model was adopted to calculate the point defect concentration of CdMnTe, and the annealing condition was obtained to maintain the minimum deviation from stoichiometry of CdMnTe. The Indium-doped CdMnTe wafers before and after Cd vapor annealing were characterized by near-infrared (NIR) transmission spectroscopy, IR transmission microscopy, I–V, and IR transmittance. The results indicated that, the Mn composition of the Indium-doped CdMnTe wafers remained unchanged, the concentrations of Te inclusions reduced from (1–5)×105 cm−3 to (1–4)×104 cm−3, the resistivity increased from (2.0–4.5)×108 Ωcm to (2.7–5.3)×1010 Ωcm, and the IR transmittance heightened from 17%–21% to 56%–59%. Therefore, it is concluded that the structural and electrical properties of the Indium-doped CdMnTe crystals were evidently improved by the stoichiometric Cd vapor annealing. [Copyright &y& Elsevier]

Photophysical properties of diketopyrrolopyrrole derivativessubstituted with oligothiophenes are investigated. All compounds arefound to be fluorescent both in solution and in the solid phase. Atlow temperature in the solid, fluorescence originates from excimer-likeexcited states. Comparison of absorption and fluorescence excitationspectra taken under matrix isolated conditions and on solid filmsshow the presence of both J- and H-type absorption bands in the solidphase. Quantum-chemical calculations, including exciton–phononcoupling to account for deviations from the Born–Oppenheimerapproximation, are performed to simulate the band shape of the lowestabsorption band in the molecular solid. The joint presence of J- andH-bands is explained by the presence of two molecules in the unitcell. The Davydov splitting is substantial for molecules with linearalkyl substituents on the nitrogen atom (on the order of 0.2 eV) butcan be reduced to almost zero by introducing branching at the β-carbonof the alkyl side chain. [ABSTRACT FROM AUTHOR]

Abstract: In this work, we developed X-ray radiation detectors with sandwich structure fabricated from nano-crystalline diamond (NCD) films. These NCD films with different grain size ranging from 15nm to 160nm were grown on silicon substrates using a hot-filament chemical vapor deposition technique. I–V measurement results indicate that with reducing of the grain size, the resistivity of diamond films decreases from 9.5×108 to 6.20×107 Ωcm and the ratio of the photocurrent to the dark-current (I ph /I d ) of the detectors decreases rapidly from 0.45 to 0.09 at an electric field of 50kV/cm. Typical spectral response to 5.9keV 55Fe X-rays shows that counting efficiency and energy resolution of NCD detectors with large grains are better than those of detectors with small grains, due to the less defects and grain-boundaries contained in the film. [Copyright &y& Elsevier]

In this article, a new regularization method is proposed and applied to the identification of multi-source dynamic loads acting on a surface of composite laminated cylindrical shell. In general terms, regularization is the approximation of an ill-posed problem by a family of neighbouring well-posed problems. Based on the construction of a new regularization operator, corresponding regularization method is established. We propose a regularization operator, thus construct a new regularization method, and prove its regular property. The present method is applied to load identification of composite laminated cylindrical shell. The transient displacement response can be obtained by the finite element method. The multi-source dynamic loads on a surface of composite laminated cylindrical shell are successfully identified, which demonstrates the efficiency and robustness of the present method. [ABSTRACT FROM AUTHOR]

Abstract: We present an improved iteration regularization method for solving linear inverse problems. The algorithm considered here is detailedly given and proved that the computational costs for the proposed method are nearly the same as the Landweber iteration method, yet the number of iteration steps by the present method is even less. Meanwhile, we obtain the optimum asymptotic convergence order of the regularized solution by choosing a posterior regularization parameter based on Morozov’s discrepancy principle, and the present method is applied to the identification of the multi-source dynamic loads on a surface of the plate. Numerical simulations of two examples demonstrate the effectiveness and robustness of the present method. [Copyright &y& Elsevier]

Abstract: The design and fabrication of a capacitive Frisch grid structure for CdZnTe (CZT) detector have been investigated in this paper. The simulation results show that a bigger ratio of L/H (metal screen ring length/device height) with the ratio of ɛr /d at 20 mm−1 (relative dielectric constant/the thickness of insulation layer) helps to compress the weighting potential towards the anode, and therefore to improve the energy resolution as showed by the experimental results. The capacitive Frisch grid structures significantly improve spectroscopic performance of planar CZT detectors. In particular, a passivation layer obtained by two-step passivation processing, combined with a Teflon tape was used for an insulated layer of the capacitive Frisch grid detector which can be applied at high voltage. A typical FWHM energy resolution of 4.58% at 662 keV was obtained for a device with dimensions of 5 × 5 × 10 mm3. [Copyright &y& Elsevier]

Abstract: In this paper, the photoluminescence (PL) spectra were detected to characterize Cd0.8Mn0.2Te crystals grown by the vertical Bridgman method. Several monocrystalline (111) face plates with dimension of 30×40×2mm3 were sliced from the as-grown Cd0.8Mn0.2Te ingot, where the PL analysis was conducted. The PL spectra revealed the neutral acceptor bound exciton (A0, X) peaks and the donor–acceptor pair (DAP) peaks. The activation energies derived from the temperature-dependent PL quenching of the (A0, X) peak was estimated to be 5.3meV and 45.8meV, which suggested the binding energy of excitons to acceptors at lower temperatures and the Auger recombination at higher temperatures. A relationship for the bandgap energy of Cd0.8Mn0.2Te as a function of temperature ranging from 10K to 300K was obtained. The composition uniformity of the (111) face Cd0.8Mn0.2Te plates were analyzed with PL spectra, which shown that the variation of Mn concentration is within 0.012 mole fraction. [Copyright &y& Elsevier]

The inverse problem of the initial condition about the boundary value of the chord vibration equation is ill-posed. First, we transform it into a Fredholm integral equation. Second, we discretize it by the trapezoidal formula method, and then obtain a severely ill-conditioned linear equation, which is sensitive to the disturbance of the data. In addition, the tiny error of right data causes the huge concussion of the solution. We cannot obtain good results by the traditional method. In this paper, we solve this problem by the Tikhonov regularization method, and the numerical simulations demonstrate that this method is feasible and effective. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the variational iteration method is applied to neutral functional-differential equations with proportional delays. Illustrative examples are given to show the efficiency of the method. We also compare the performance of the method with that of a particular Runge–Kutta method and a one-leg -method. [Copyright &y& Elsevier]

Charge carrier mobility is at the center of organic electronic devices. The strong couplings between electrons and nuclear motions lead to complexities in theoretical description of charge transport, which pose a major challenge for the fundamental understanding and computational design of transport organic materials. This tutorial reviewdescribes recent progresses in developing computational tools to assess the carrier mobility in organic molecular semiconductors at the first-principles level. Some rational molecular design strategies for high mobility organic materials are outlined. [ABSTRACT FROM AUTHOR]

Abstract: We present three cubically convergent methods for choosing the regularization parameters in linear inverse problems. The detailed algorithms are given and the convergence rates are estimated. Our basic tools are Tikhonov regularization and Morozov''s discrepancy principle. We prove that, in comparison with the standard Newton method, the computational costs for our cubically convergent methods are nearly the same, but the number of iteration steps is even less. Numerical experiments for an elliptic boundary value problem illustrate the efficiency of the proposed algorithms. [Copyright &y& Elsevier]

• A new iteration regularization algorithm is proposed. • The proposed iteration regularization algorithm is strictly proved. • The present method is powerful for load identification for stochastic structure. • The newly developed method saves computational cost remarkably compared with MCS. • Numerical simulations validate the obtained theoretical results. In this paper, we propose a novel fast convergence iterative regularization method on the basis of a new iterative regularization operator to solve the dynamic load identification of stochastic structures. Firstly, the validity and convergence of the proposed algorithm is proved by strict mathematical theory and numerical results of engineering example. Secondly, the dynamic load identification of uncertain structures can be transformed into a series of deterministic inverse problems by the matrix perturbation method. Finally, we also assess the statistical characteristics of identified loads using the statistical theory. Particularly, the proposed method successfully solves the dynamic load identification of stochastic structure. Numerical simulations are given to validate the feasibility of the presented method in this paper. [ABSTRACT FROM AUTHOR]

Both crystal packing and molecular size have strong influences on the charge mobility for organic semiconductors. The crystal structures for oligothiophene (nT) can be roughly classified into two types: the Z = 2 (two molecules in one unit cell) or high temperature (HT) phase and the Z = 4 or low temperature (LT) phase. Through first-principles calculations within the Marcus electron transfer theory coupled with random walk simulation for room temperature charge diffusion constants, we found that the hole mobility of the HT phase is about 3–4 times larger than that of the LT phase because the molecular packing in the HT phase favors the hole transfer (i.e., the frontier orbital wave function phases of the dimer are constructive, which tends to maximize the overlap), while for the LT phase, the molecules are packed in a position that reduces the intermolecular orbital overlap due to phase cancellation. As the molecular size increases from 2T to 8T, the hole mobility tends to increase because the reorganization energy decreases with the chain length. The influences of crystal packing and molecular size on the hole mobility of oligothiophenes were investigated theoretically. The mobility tends to increase as the molecular size increases from 2T to 8T. As compared to the Z = 4 (four molecules in one unit cell) crystal phase, the Z = 2 phase favors hole transfer. [ABSTRACT FROM AUTHOR]

Abstract: The effect of the polarity of the applied bias voltage on the electrical response and the charge collection efficiency of sandwich structural diamond film detectors under 5.5 MeV 241Am alpha-particle irradiation is investigated. Results show that, under the alpha irradiation the detector applied with a negative bias voltage has a higher response current and a better signal-to-noise ratio than that applied with a positive bias voltage. A better energy resolution of about 25.0% is obtained for the detector applied with a negative bias voltage, and however 38.4% for that with a positive bias voltage. Raman scattering studies demonstrate that these changes with the polarity of the bias voltage may be attributed to the different structural imperfection distributions along the thickness direction of the diamond film. [Copyright &y& Elsevier]

An undoped p-type nanocrystalline diamond (NCD) film was grown by an electron assisted hot filament chemical vapor deposition (EA-HFCVD) technology on an n-type single-crystalline Si substrate to fabricate p-NCD/n-Si heterojunction. The structure and morphology of the NCD film, which was analyzed by Raman spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM), showed that the film consisted of 40–60 nm polycrystalline nano-grains. The results showed that with EA-HFCVD method, not only an undoped NCD film with high conductivity but also a p–n heterojunction diode between the NCD film and n-Si substrate was fabricated successfully. The p-NCD/n-Si heterostructure was also used for ultraviolet (UV) photodetector application. Operating at a bias voltage of 10 V, this photodetector showed a significant discrimination between UV and visible light, and the UV/visible-blind ratio was about three orders of magnitude. [ABSTRACT FROM AUTHOR]

Abstract: In order to grow diamond film on alumina ceramic, it is essential to control the diamond nucleation properly. Under a gas pressure lower than that used for growth, a high nucleation density of diamond films on alumina, as high as 108/cm2, is successfully achieved by microwave plasma-enhanced chemical vapor deposition method. Based on this, [100]-textured diamond films are successfully deposited on alumina by controlling the substrate temperature. From the results on SEM, XRD and Raman measurements, the substrate temperature has a strong influence on the textured growth and quality of diamond films on alumina substrates. Too low or too high temperature cannot obtain [100]-textured and good-quality films. The optimum substrate temperature range, for the growth of [100]-textured and good-quality diamond films on alumina, should be 800∼860 °C in our experiments. [Copyright &y& Elsevier]