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Objective : The facial nerve trace on the ipsilateral side of the vestibular schwannoma was reconstructed by diffusion tensor imaging tractography to identify the adjacent relationship between the facial nerve and the tumor, and to improve the level of intraoperative facial nerve protection.Methods : The clinical data of 30 cases of unilateral vestibular schwannoma who underwent tumor resection via retrosigmoid approach were collected between January 2019 and December 2020. All cases underwent magnetic resonance imaging examination before operation. Diffusion tensor imaging and anatomical images were used to reconstruct the facial nerve track of the affected side, so as to predict the course of the nerve and its adjacent relationship with the tumor, to compare the actual trace of the facial nerve during operation, verify the degree of coincidence, and evaluate the nerve function (House-Brackmann grade) after surgery.Results : The facial nerve of 27 out of 30 cases could be displayed by diffusion tensor imaging tractography, and the tracking rate was 90% (27/30). The intraoperative locations of facial nerve shown in 25 cases were consistent with the preoperative reconstruction results. The coincidence rate was 92.6% (25/27). The facial nerves were located on the anterior middle part of the tumor in 14 cases, anterior upper part in eight cases, anterior lower part in seven cases, and superior polar in one case. Intraoperative facial nerve anatomy was preserved in 30 cases. Among the 30 patients, total resection was performed in 28 cases and subtotal resection in two cases. The facial nerve function was evaluated 2 weeks after operation, and the results showed grade I in 12 cases, grade II in 16 cases and grade III in two cases.Conclusion : Preoperative diffusion tensor imaging tractography can clearly show the trajectory and adjacent position of the facial nerve on the side of vestibular schwannoma, which is beneficial to accurately identify and effectively protect the facial nerve during the operation, and is worthy of clinical application and promotion.

The electron transition between oxygen vacancies and cationic vacancies shortens the band gap of KDP crystals.

S parameters of the ADP samples tend to be consistent with little change with the increase of depth and Fe3+ concentration.

The FeK2+ defect introduces two defect states (at 2.4 eV and 6.6 eV) into the bandgap of the KDP crystal as well as absorption peaks at around 278 nm in the xy plane.

To develop and validate anA total of 280 patients with BPN (n=128) or MPN (n=152) were collected retrospectively and randomized into the training set (n=196) and validation set (n=84). Pretherapeutic clinicobiological markers, PET/CT metabolic features and radiomic features were analyzed and selected to develop prediction models by the machine-learning method [Least Absolute Shrinkage and Selection Operator (LASSO) regression]. These prediction models were validated using the area under the curve (AUC) of the receiver-operator characteristic (ROC) analysis and decision curve analysis (DCA). Then, the factors of the model with the optimal predictive efficiency were used to constructed a nomogram to provide a visually quantitative tool for distinguishing BPN from MPN patients.We developed 3 independent models (Clinical Model, Radiomics Model and Combined Model) to distinguish patients with BPN from those with MPN in the training set. The Combined Model was validated to hold the optimal efficiency and clinical utility with the lowest false positive rate (FPR) in classifying the solid pulmonary nodules in two sets (AUCs of 0.91 and 0.94, FPRs of 18.68% and 5.41%, respectively; P0.05). Thus, the quantitative nomogram was developed based on the Combined Model, and a good consistency between the predictions and the actual observations was validated by the calibration curves.This study presents a machine-learning nomogram integrated clinico-biologico-radiological features that can improve the efficiency and reduce the FPR in the noninvasive differentiation of BPN from MPN.

The structure, total system energies, electronic structures and optical absorption of the [010] screw dislocation in potassium dihydrogen phosphate (KH2PO4, KDP) crystals are investigated in the framework of the density functional theory with the HSE06 functional. To describe the complete stress field, six supercells under different shear stress caused by the [010] dislocation are constructed. The results have confirmed that the shear stress will deform the crystal structure and narrow the band gap. One of the more significant findings to emerge from this study is that when the crystal is under a large shear stress, in other words, in the vicinity of the dislocation core the dehydration will occur and it will enhance the linear and nonlinear absorption of the KDP crystal. The H atom and hydroxyl are contributed by different PO4 tetrahedra, respectively. The data reported here appear to support the assumption that the [010] dislocation has a harmful influence on the resistance of KDP to the laser irradiation. In spite of its limitations, these findings have significant implications to understand how to improve LIDT of the KDP crystal and have a number of important implications for future practice.

Defects have always been considered as one of the important factors to reduce the laser damage thresholds of potassium dihydrogen phosphate (KH2PO4, KDP). However, crystal defects often do not exist singly but combine with each other to form clusters. In this study, hybrid density functional theory was used to investigate how the cluster defects affect the damage threshold of KDP crystals. The concentration of oxygen vacancy defects has little effect on the electronic structure, only influencing the torsion of the surrounding bond. Moreover, the cluster defects comprising FeP2− + VO2+ could cause a slight local variation of the lattice for KDP crystals. The defect state induced by FeP2− defect could introduce three defect states at 0.5, 1.2 and 4.0 eV, respectively. It could also introduce absorption peaks at around 200 nm in the yz plane. When the FeP2− + VO2+ cluster defect forms, the defect state shifts to CBM at about 1.0 eV as a whole due to electron depletion and accumulation for the H atom and its attached O atom. It could have an influence on electronic and optical properties by strengthening the charge transfer along the direction of x in the crystals. The calculation results could provide a good suggestion to improve the quality of the crystals by decreasing the concentration of the cluster defects in KDP crystal.

Single atom catalysts (SAC) for water splitting hold the promise of producing H2 in a highly efficient and economical way. As the performance of SACs depends on the interaction between the adsorbate atom and supporting substrate, developing more efficient SACs with suitable substrates is of significance. In this work, inspired by the successful fabrications of borophene in experiments, we systematically study the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) activities of a series of 3d transition metal-based SACs supported by various borophene monolayers (BMs=α_sheet, α1 _sheet, and β1 _sheet borophene), TM/BMs, using density functional theory calculations and kinetic simulations. All of the TM/BMs systems exhibit superior HER performance compared to Pt with close to zero thermoneutral Gibbs free energy (ΔGH* ) of H adsorption. Furthermore, three Ni-deposited systems, namely, Ni/α_BM, Ni/α1 _BM and Ni/β1 _BM, were identified to be superior OER catalysts with remarkably reduced overpotentials. Based on these results, Ni/BMs can be expected to serve as stunning bifunctional electrocatalysts for water splitting. This work provides a guideline for developing efficient bifunctional electrocatalysts.

Following the implementation of the strictest water resource management system in China, it has become increasingly important to understand and improve the surface water quality and the rate at which water function zones reach the water quality standard. Based on the monthly monitoring data from 450 monitoring sites at the provincial borders of 27 provinces in China in 2019, the overall surface water quality at provincial boundaries in China was as follows: 61.7% of the water was classified under Class I–III; and 5%, 8.6%, and 12.2% of the water was classified under Class IV, V, and inferior V, respectively. The main standard items are DO, CODMn, COD, BOD5, NH3-N, and TP. The Canadian Council of Ministers of the Environment-water quality index (CCME-WQI) showed that the provincial boundary water quality exceeded the fair level, and F1 was the most influential factor. Then, 27 factors that directly or indirectly affect the water quality of surface water at the provincial boundaries of 27 provinces were identified, and the indirect influencing factors were integrated into the ecological environmental quality index and human activities quantitative index. Finally, the 27 factors were integrated into six factors, and the relationship between these indicators and CCME-WQI as well as the concentration of influencing elements with respect to regulatory standard limits were analyzed. The proportion of building land was the most significant factor affecting the quality of the aquatic environment in provincial boundaries. In addition, the economic development level, proportion of farmland, and degree of social development were identified as significant influencing factors. The six factors have different degrees of impact on the concentrations of major elements with respect to standard limits. This study basically explores water resource management and offers significant reference and guidelines for the improvement of the quality of surface water at provincial boundaries in China.

Objective: The purpose of this study was to determine the effect of browsing TikTok for 20 min on patients’ preoperative anxiety. Method: A randomized controlled trial was conducted at the Department of Anesthesiology of The First Affiliated Hospital, Zhejiang University School of Medicine from January 2021 to March 2021. The 80 patients were randomly divided into two groups. The experimental group browsed TikTok for 20 min, but the control group did not. Preoperative anxiety was measured with the help of the Amsterdam Preoperative Anxiety and Information Scale (APAIS) and anxiety visual analog test (AVAT). Preoperative anxiety, systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR) were checked before and after 20 min of TikTok browsing. Patient satisfaction with anesthesia was evaluated as the patient entered and exited the operating room. Results: The pretest APAIS scores, AVAT scores, vital signs and patient satisfaction were similar in both groups (p > 0.05). Compared with the control group, patient anxiety levels and systolic blood pressure decreased significantly after 20 min of TikTok browsing (p < 0.05), and patient satisfaction with anesthesia was significantly higher (p < 0.05). In the experimental group, after patients browsed TikTok for 20 min, all of the physiological and behavioral variables of anxiety were significantly reduced (p < 0.05). Conclusions: TikTok is a popular, simple, effective, noninvasive and inexpensive method for decreasing preoperative anxiety, and browsing TikTok can lower a patient's blood pressure and heart rate to some extent.

Intrinsic point defects are regarded as one of the dominant factors that can induce initial structural breakdown under laser irradiation and reduce the laser damage thresholds of potassium dihydrogen phosphate (KDP) and its analog ammonium dihydrogen phosphate (ADP) crystals. In this work, we theoretically investigated the structural stress and extra optical absorption induced by the cation defects (Hi, VP, VK, and VN) in both crystals. VP5− is identified as one of the main defects that can contribute to the reduced laser damage threshold of KDP. It can collapse the PO43− skeletal structure of KDP and introduce extra optical absorption at 310–620 nm. The relatively higher laser damage threshold of ADP is attributed to the difficulties in forming VP defects in the crystal. The dominant cation defects Hi+ and VN3+ in ADP cause less local stress than VP5− in KDP and do not introduce any defect states and extra optical absorption that may reduce the optical damage threshold. These calculation results agree well with the experiments. It is therefore suggested to control the VP concentration during the KDP crystal growth and treatment to effectively enhance its resistance to laser irradiation.

The structures and properties of one-dimensional (1D) sandwich molecular wires constructed with altering 3d transition metal (TM) and the metallofullerene (TM@C60) entities, [TM&(TM@C60)]∞, are stu...

Purpose The purpose of this paper is to shed light on the deleveraging impact of the anti-corruption campaign since the 18th National Congress of the Communist Party of China (CPC) on private firms with political connections, relative to those without political connections. Design/methodology/approach In this paper, taking the anti-corruption campaign employed from the end of 2012 as an exogenous shock, the authors design a quasi-experiment difference-in-difference approach to examine how the loss and failure of political connections impacts private firms’ debt financing. Findings The authors find that the loss and failure of political connections following the anti-corruption campaign since the 18th CPC National Congress causes the yearly new debt ratios of treatment firms with political connections to decrease, relative to those of control firms without political connections. This outcome is more pronounced for provinces with more cadres excluded in the anti-corruption campaign since the 18th CPC National Congress, which rendered politically connected firms susceptible to lose connections with central or provincial cadres. To explore the mechanism, the authors find that following the anti-corruption campaign since the 18th CPC National Congress, politically connected firms limit rent-seeking activities, whereas resource acquisition is weakened. The authors also find that the impact of the anti-corruption campaign since the 18th CPC National Congress on the debt financing of politically connected firms, relative to their counterparts, is more pronounced for groups with high levels of information asymmetry and for less explicit guarantee groups. Finally, politically connected firms are more likely to be dominated by internal funds in dealing with a loss of advantages in debt financing, compared with their counterparts without political connections. Research limitations/implications The findings in this study suggest that the loss or failure of previous political connections following Xi’s anti-corruption campaign make politically connected firms lose the advantages in debt financing through the rent-seeking, resource acquisition, information asymmetry, implicit guarantee channels, which provide new evidence for research on the impact of the anti-corruption campaign since the 18th CPC National Congress on private firms’ financing behaviors via the loss or failure of existing political connections. Practical implications The findings in the study will have some inspiration for policy makers and entrepreneur. Originality/value This study provides new evidence on the different impacts of Xi’s anti-corruption campaign on private firm’s debt financing between politically connected and unconnected firms.

DADP crystals with different deuterium as 0%, 30%, 50%, and 70% were grown via traditional temperature reduction method and the samples were gained from the as-grown crystals in the directions of Ι -type (θ = 90°,φ = 45°). The transmittance spectrum, UV absorption spectrum, and Raman spectrum were implemented to describe the properties of DADP crystals, and the deuteration of ADP crystals makes a difference on the absorption peaks in these spectrums. Particularly, the optical band gap Eg decreases with the accretion of deuterium content. The third-order nonlinear optical characteristics were systematically represented and tested by means of Z-scan measurements with Pico-second pulse laser irradiation at λ = 355 nm, with the results listing the reverse saturable absorption and self-focusing effect. The investigations may contribute to replenish and elucidate the application and laser-induced damage of DADP crystals.

Ammonium dihydrogen phosphate (NH4H2PO4, ADP) is an excellent nonlinear optical crystal and has had wide application. It was the same type of potassium dihydrogen phosphate (KH2PO4, KDP) with a similar crystal structure. The difference in structure and properties of ADP crystal in the presence of defects, especially cluster defects, was one of the important issues of concern in the research. In this work, first-principles calculation, coupled with HSE06 functional and the van der Waals-Wannier function method, was applied to investigate the structural stability and electronic properties induced by oxygen vacancy cluster defects and FeP2-+VO2+ cluster defects. And some spectra experiments, such as Raman spectroscopy, the Fourier transform infrared spectroscopy and the ultraviolet absorption spectroscopy, were also applied to investigate the detailed influence for ADP crystal doped with different Fe3+ concentration, which was grown with the “point-seed” rapid growth method. Combined with the theoretical results and the spectra tests, it confirmed that the structural changes in ADP crystal caused by oxygen vacancy cluster defect and FeP2-+VO2+ cluster defect were smaller than that in KDP crystal, mainly due to the restriction of hydrogen bonds and NH4+ group. With the increase of defect concentration, the microstructure stress could also damage the crystal structure due to the microscopic stress induced by Fe3+. The defect states moved towards right from 1.1 eV to 6.6 eV with the concentration of oxygen vacancy increasing. Similarly, the defect state composed of Fe 3d and O 2p states induced by FeP2- defect also moved to the conduction band minimum. The absorption peaks around 220-350 nm induced by FeP2- defect and FeP2-+VO2+ cluster defect were along the xy plane. It provided a good suggestion based on the calculation that it was very important to minimize defects or control cluster defect concentration during crystal growth.

Various uncertain influencing factors and incomprehensible mechanisms have posed daunting challenges to the management and treatment of regional surface water environment quality. The unified measures and the “one-size-fits-all” management approach limit the treatment effectiveness. Therefore, considering natural and human activities which are major factors affecting the surface water environment quality, the present study proposed a set of zoning management and control schemes for nitrogen and phosphorus concentrations in surface water based on its natural attributes. Selecting DEM, rainfall, vegetation type, soil type, and land use, and employing “grid transformation”, “data extraction”, “attribute superposition” of GIS software and “correlation analysis”, “cluster analysis”, and “principal component analysis” of SPSS software, the Haihe River Basin was divided into the prevention zone, the control zone, and the non-control zone with different natural attribute sets by the correlation coefficient R2 and the nitrogen and phosphorus pollution therein. Based on the nitrogen and phosphorus data of 276 surface water quality monitoring sites, the multiple nonlinear stepwise regression analysis was conducted to construct the relationship between a single water quality indicator and its natural attributes in the three zones. The results are of essential practical significance to surface water environment quality zoning management and survey in the Haihe River Basin. Meanwhile, it provides innovative insights into environmental zoning management in other regions.

Xu, M.X., 2020. Influence of optimal allocation of water resources on the economic development of coastal industries. In: Guido Aldana, P.A. and Kantamaneni, K. (eds.), Advances in Water Resources, Coastal Management, and Marine Science Technology. Journal of Coastal Research, Special Issue No. 104, pp. 612–616. Coconut Creek (Florida), ISSN 0749-0208.According to the theory of variable fuzzy recognition and the optimal allocation model of water resources, this paper establishes an evaluation index system of water resources optimal allocation scheme to evaluate the optimal allocation scheme of water resources. A case study on the impact of the optimal allocation of water resources on the economic development of coastal industries, taking a coastal city as a research object, concludes that the optimal allocation of water resources is relevant to the economic development of coastal industries. With the development of the economy, the water demand of various industries has gradually increased. After optimizing the allocation of water resources, the water consumption of the primary, secondary and tertiary industries in the region has shown a downward trend.

The hydrogen vacancy (VH) is the most common point defect that may lead to optical damage of potassium dihydrogen phosphate (KDP) and its analog ammonium dihydrogen phosphate (ADP), further limiting their practical application in high-power laser systems. In this work, we have grown KDP and ADP crystals by using a rapid growth method, and investigated the physical origin of the different stability of VH as well as the defect-induced electronic structure and optical absorption in KDP and ADP crystals. The inclusion of van der Waals correction to density functional theory calculations is found to have little influence on VH energetics of KDP whereas it largely reduces the charge transition level e(+/-) of VH by >2 eV in ADP. It is found that hydrogen vacancies mainly contribute to the redshift of the measured absorption edges of both KDP and ADP crystals. Owing to the varied lattice environments and locations, the VH defects exhibit different stability, and electronic and optical properties in KDP and ADP crystals. Notably, the extra optical absorption caused by the positively-charged VH in KDP could be largely reduced by decreasing the defect concentration, whereas ADP exhibits defect-location dependence - the optical damage center of the VH in the NH4+ group could not be eliminated because of electron capture of its neighboring N atoms. The calculation results help us to better understand the origin of laser damage in KDP and ADP crystals.

By dissolving sodium chloride ($\mathrm{Na}\mathrm{Cl}$) in liquid water, we realize an obvious enhancement of stimulated Raman scattering (SRS). Compared with pure water, the performance improvements include spectrum purification, an increased Raman gain, a decreased pump threshold, and an increased conversion efficiency. In the best SRS results, the pump threshold decreases by 45% and the maximum conversion efficiency increases by 10.4%. Then, water becomes a typical Raman-scattering medium that generates narrowband light. Moreover, we find that the bulk structure of water and $\mathrm{Na}\mathrm{Cl}$ solutions can be analyzed in detail by combining the principles of SRS and analysis of the SRS spectra. In water, the $\mathrm{O}---\mathrm{H}$ stretching band is proved to be a superposition of stretching modes of different water clusters. For the solution, the $\mathrm{O}---\mathrm{H}$ stretching vibration of water molecules in hydration shells around ${\mathrm{Cl}}^{\ensuremath{-}}$ ions can be obtained directly, and its variation with respect to solute concentration is investigated using SRS spectra. The superior SRS properties of solutions originate from the hydration shell around the ${\mathrm{Cl}}^{\ensuremath{-}}$ ions. This work suggests that SRS is a promising approach to identifying structures in water and $\mathrm{Na}\mathrm{Cl}$ solutions, and that it can easily be extended to other liquids and solutions.

Marine environmental monitoring technology is the support of marine development, and its development level and innovation capability have become important criteria for measuring a country’s marine science and technology indicators. In order to meet the application demand of large-scale and high-density deployment of marine observation network, a planar open seven-electrode conductivity and platinum resistance temperature integrated sensor is developed by using Micro Electro Mechanical System(MEMS) technology, combined with semiconductor micro and nano precision processing technologies such as mask lithography and physical sputtering. The measurement principle, probe design preparation, packaging and calibration method of this conductivity temperature sensor are presented. By calibrating and fitting the measurement data of this sensor, good measurement accuracy results were obtained. The miniaturized conductivity temperature sensor has the advantages of small size, low power consumption, low cost and high accuracy of probe processing, high batch consistency, and fully meets the application requirements of marine observation network.

A spatial body object morphology analysis basically consists of the volume parameter. However, the challenge lies in the volume calculations of irregular objects. A point cloud slicing method (PCSl...