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Geothermal energy, as a clean and renewable resource distributed worldwide, has received extensive focus in recent years. With the improvement in drilling and logging technology, the depth of geothermal exploration has gradually increased. Carbonate reservoirs are presently the main layer for geothermal development and use in China that have the characteristics of wide distribution, large reserves, and easy reinjection. The current use is limited to the strong karst development zone, approximately 200 m at the top of the reservoirs. Because of the low permeability and strong heterogeneity, the deep carbonate geothermal reservoirs cannot be commercially developed. This study aims to solve the key technical problems of efficiently developing deep carbonate geothermal reservoirs with extreme thickness. The target section was selected by analyzing comprehensive logging and fracture imaging logging data. An innovative simulation technology combining hydraulic jetting and acid fracturing is developed, which has the characteristics of fixed-point fracturing, effective sealing, strong penetration, and a large stimulation range. A production enhancement test was conducted for carbonate geothermal wells in the following order: comprehensive logging, imaging logging, casing cementing, perforation, pumping test, small pressure test, hydraulic injection acid fracturing, pumping test (after fracturing), and other construction processes. Comprehensive logging is an effective means to interpret the macroscopic pore and permeability properties of a reservoir and can be used to initially select the target geothermal reservoir. Fracture imaging logging can provide a more intuitive understanding of fracture development and distribution characteristics. The results show that the fracture density of geothermal well D22 does not decrease substantially with increasing depth, and the fracture width tends to decrease with depth clearly. The experimental geothermal well D22, which has the largest thickness of carbonate geothermal reservoir exposed in the Xiong'an New Area, was selected to perform a pilot field test of stimulation. The results show that the water inflow of the target section at 3024–3174 m increased from 4.72 m3·h−1 before stimulation to 44.10 m3·h−1 after stimulation, increasing by 8.3-fold. The unit water inflow increased from 0.024 m3·(h·m)−1 before stimulation to 0.745 m3·(h·m)−1 after stimulation, increasing by 30-fold. The reservoir permeability coefficient increased from 4.4×10−3 m·d−1 to 146.3×10−3 m·d−1. The wellhead water temperature increased from 60.0 °C before stimulation to 66.5 °C after stimulation. Therefore, the development potential of deep and thick carbonate geothermal reservoirs can be substantially improved through the developed stimulation. This research can provide technical support for the large-scale development of geothermal resources in China.

Disturbance of the cholinergic system plays a crucial role in the pathological progression of neurological diseases that cause dyskinesia-like behaviors. However, the molecular mechanisms underlying this disturbance remain elusive. Here, we showed that cyclin-dependent kinase 5 (Cdk5) was reduced in cholinergic neurons of midbrain according to the single-nucleus RNA sequencing analysis. Serum levels of CDK5 also decreased in patients with Parkinson’s disease accompanied by motor symptoms. Moreover, Cdk5 deficiency in cholinergic neurons triggered paw tremors, abnormal motor coordination, and motor balance deficits in mice. These symptoms occurred along with cholinergic neuron hyperexcitability and increases in the current density of large-conductance Ca2+-activated K+ channels (BK channels). Pharmacological inhibition of BK channels restrained the excessive intrinsic excitability of striatal cholinergic neurons in Cdk5-deficient mice. Furthermore, CDK5 interacted with BK channels and negatively regulated BK channel activity via phosphorylation of threonine-908. Restoration of CDK5 expression in striatal cholinergic neurons reduced dyskinesia-like behaviors in ChAT-Cre;Cdk5f/f mice. Together, these findings indicate that CDK5-induced phosphorylation of BK channels involves in cholinergic-neuron-mediated motor function, providing a potential new therapeutic target for treating dyskinesia-like behaviors arising from neurological diseases.

In this paper, a direct numerical simulation (DNS) of dielectric fluid flow subjected to unipolar injection under an alternating current (AC) electric field is carried out. The effect of frequency f of pulsed direct current (PDC) and AC on the transient evolution of electroconvection and their subcritical bifurcations are investigated in details. Electroconvection under PDC or AC tends to exhibit oscillating flow due to the periodic boundary condition of charge density and potential compared to the direct current (DC) case. The results demonstrate that under the PDC field, the linear criterion Tc decreases with increasing frequency, while the nonlinear stability criterion Tf is hardly affected. Under the AC field, a critical frequency fc = 0.0316 is found, which separates electroconvection into two typical flow regimes—periodic flow regime (f

DNA G-quadruplexes occur in oncologically relevant regions, thus are interesting targets for cancer research and treatment. Here, the authors solved the 1:1 and 4:2 (ligand/DNA) NMR structures of human telomeric DNA in complex with platinum(II)-tripod ligand and show that the binding is dynamic.

In this study, sodium alginate (SA), dimethyl dodecyl betaine (BS), and chitosan (CS) were used for single, binary, and ternary modifications on the surface of semi-carbonized fibers (Sf) prepared using acrylic fiber. Batch method was used to investigate the adsorption characteristic of oxytetracycline (OTC) on the tested materials, and the effects of pH, temperature, and ionic strength on oxytetracycline adsorption were compared. The structural particularities of the tested materials was studied using scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR). Results showed that: (1) Langmuir model can better fitted the adsorption isotherms of OTC than Henry and Freundlich models, with the maximum adsorption capacity (qm) maintained at 16.11– 65.25 mmol/kg. The qm of oxytetracycline presented the trend of ternary > binary > single modification. (2) In the pH range of 1–9 and ionic strength range of 0.01–0.5 mol/L, the adsorption amount of OTC on different modified Sfs increased first and then decreased with increasing pH and ionic strength, reaching the maximum value at pH 5 and ionic strength of 0.1 mol/L. (3) OTC adsorption on different modified Sfs increased with the increase in temperature, and the adsorption was a spontaneous, endothermic, and entropy-increasing process, which conformed to the pseudo-second-order kinetic equation. (4) SEM and FTIR results proved that the modifiers were modified on the surface and that they changed the surface properties of Sf. The adsorption amount of OTC on 100SA/BS/ CS-Sf still reached about 50% of the original material after three times of regeneration. [ABSTRACT FROM AUTHOR]

To prospectively evaluate the feasibility, safety and efficacy of the percutaneous pedicle screw fixation through the pedicle of fractured vertebra in the treatment of type A thoracolumbar fractures using Sextant system in the retrospective non- randomized case-control study.

[Display omitted] Oral administration of chemotherapy agents, such as docetaxel (DTX), is expected to reduce side effects significantly and increase dosing frequency. However, they often suffer from poor oral bioavailability, impeding their oral application. Dietary lipids such as triglycerides favor lymphatic transport nor vein system, bypassing the first-pass metabolism. Inspired by this concept, we developed a triglyceride-like prodrug of DTX (named as OATG) and explored the effect of lipid types on the OATG oral delivery. The plasma profile in rats revealed that long chain triglyceride (LCT)-based lipid formulations (LBLF) were more promising for OATG delivery than medium chain triglyceride (MCT) ones. The OATG LBLF elicited a markedly enhanced absorption compared with oral Taxotere or DTX LBLF, resulting in relative bioavailability 6.11 or 2.47-fold higher, respectively. The coincident intestinal behaviors of lipid excipients and TG-like prodrug facilitate the oral absorption of the prodrug. The effectiveness of the prodrug formulation was also examined in beagles with absolute bioavailability up to 41.08%, in sharp contrast to that of control DTX group (8%). Besides, the OATG oral formulation could be schedule-intensively administrated with no hypersensitivity, gastrointestinal and hematological toxicity. The current strategy provides an effective lipid formulation and a promising chance for chemotherapy at home. [ABSTRACT FROM AUTHOR]

An active fault-tolerant pulse-width-modulated tracker using the nonlinear autoregressive moving average with exogenous inputs model-based state-space self-tuning control is proposed for continuous-time multivariable nonlinear stochastic systems with unknown system parameters, plant noises, measurement noises, and inaccessible system states. Through observer/Kalman filter identification method, a good initial guess of the unknown parameters of the chosen model is obtained so as to reduce the identification process time and enhance the system performances. Besides, by modifying the conventional self-tuning control, a fault-tolerant control scheme is also developed. For the detection of fault occurrence, a quantitative criterion is exploited by comparing the innovation process errors estimated by the Kalman filter estimation algorithm. In addition, the weighting matrix resetting technique is presented by adjusting and resetting the covariance matrix of parameter estimates to improve the parameter estimation for faulty system recovery. The technique can effectively cope with partially abrupt and/or gradual system faults and/or input failures with fault detection.

With the rapid development of 3D scanners, the cultural heritage artifacts can be stored as a point cloud and displayed through the Internet. However, due to natural and human factors, many cultural relics had some surface damage when excavated. As a result, the holes caused by these damages still exist in the generated point cloud model. This work proposes a multi-scale upsampling GAN (MU-GAN) based framework for completing these holes. Firstly, a 3D mesh model based on the original point cloud is reconstructed, and the method of detecting holes is presented. Secondly, the point cloud patch contains hole regions and is extracted from the point cloud. Then the patch is input into the MU-GAN to generate a high-quality dense point cloud. Finally, the empty areas on the original point cloud are filled with the generated dense point cloud patches. A series of real-world experiments are conducted on real scan data to demonstrate that the proposed framework can fill the holes of 3D heritage models with grained details. We hope that our work can provide a useful tool for cultural heritage protection. [ABSTRACT FROM AUTHOR]

Mental health is a major public health issue that affects social development. This study aims to explore the psychological state of residents of Hainan Island and its influencing factors during the COVID-19 pandemic and to provide a scientific basis for the formulation of psychological counseling measures to be used after the pandemic. We used the nonprobability snowball sampling method to conduct an online survey from February 21 to February 28, 2020, and collected a sample of 533 respondents. Using a binary logistic regression model and network analysis, the psychological state of residents and the main factors were analyzed during the concentrated outbreak of COVID-19 (from January 20 to February 16, 2020). The study found that during the pandemic, 92.7% of the respondents were in a poor state of mind, and 54.2% experienced severe psychological stress. The mental state is spatially expressed as a pattern of "high in the middle and low in the surroundings." Second, within the four-week sample, the overall psychological tension showed an inverted U-shaped trend. Respondents feeling stressed were most common in the second week, when they accounted for 87.99% of the total. Third, individual characteristics such as gender, age, fixed expenditure, and family size significantly affect the mental state. Women, the elderly, residents with fixed expenditures, and residents with large families are at greater risk of psychological stress. Finally, external factors such as the distance between residents and the location of cases and the node degree of the pandemic transmission network have a significant impact on the psychological state. However, residents in the least developed areas of Hainan Island, which are far away from active cases and have a low node degree, are more prone to psychological pressure. The government needs to pay special attention to these groups when constructing a long-term mechanism of psychological crisis intervention and increase public health resource investment in underdeveloped areas. [ABSTRACT FROM AUTHOR]

A life‐cycle assessment (LCA) study was completed to assess the environmental impacts of an on‐site wastewater treatment system in the fresh‐cut fruit processing industry consisting of a membrane bioreactor (MBR), followed by reverse osmosis (RO) and ultraviolet (UV) disinfection. The system boundaries comprised raw materials extraction and processing, transportation, construction, operation, and waste disposal. SimaPro 8.0.4.26 was used as the software tool, supported by two impact assessment methods (ReCiPe v1.11 and TRACI v2.1). Analysis showed that the treatment capacity of the MBR and tertiary technologies contributed the least damage to the ecosystem when compared with the other three scenarios and can provide water for reuse. Treating wastewater in municipal wastewater treatment plants (WWTPs) mitigated eutrophication like the MBR system but resulted in more environmental impacts from climate change and human health when compared with the on‐site treatment system. Findings will be informative to stakeholders in the fresh‐cut agri‐food sector seeking input into selecting the appropriate treatment approach, with water reuse a goal. Practitioner Points: Life‐cycle analysis was completed on a fruit processing facility using MBR + RO + UV.On site treatment with MBR + RO UV provides least amount of environmental impact.Use of MBR + RO + UV treatment on fruit wastewater allows for water reuse.ReCiPe v1.11 and TRACI v2.1 give similar LCA results, with TRACI recommended for North American analysis. [ABSTRACT FROM AUTHOR]

The nonlinear dynamical behaviors of economic models have been extensively examined and still represented a great challenge for economists in recent and future years. A proposed boundedly rational game incorporating consumer surplus is introduced. This paper aims at studying stability and bifurcation types of the presented model. The flip and Neimark–Sacker bifurcations are analyzed via applying the normal form theory and the center manifold theorem. This study helps determine an appropriate choice of decision parameters which have significant influences on the behavior of the game. The duopoly game that is formed by considering bounded rationality and consumer surplus is more realistic than the ordinary duopoly game which only has profit maximization. And then, some numerical simulations are provided to verify the theoretical analysis. Finally, we compare the dynamical behaviors of the built model with that of Bischi–Naimzada model so as to better understand the performance of the duopoly game with consumer surplus. [ABSTRACT FROM AUTHOR]

In this paper, a discrete-time dynamic duopoly model, with nonlinear demand and cost functions, is established. The properties of existence and local stability of equilibrium points have been verified and analyzed. The stability conditions are also given with the help of the Jury criterion. With changing of the values of parameters, the system shows some new and interesting phenomena in terms to stability and multistability, such as V-shaped stable structures (also called Isoperiodic Stable Structures) and different shape basins of attraction of coexisting attractors. The eye-shaped structures appear where the period-doubling and period-halving bifurcations occur. Finally, by utilizing critical curves, the changes in the topological structure of basin of attraction and the reason of "holes" formation are analyzed. As a result, the generation of global bifurcation, such as contact bifurcation or final bifurcation, is usually accompanied by the contact of critical curves and boundary. [ABSTRACT FROM AUTHOR]

Spinal supraspinous ligament (SL) osteogenesis is the key risk of ankylosing spondylitis (AS), with an unclear pathogenesis. We previously found that transforming growth factor β1 (TGF‐β1), bone morphogenetic proteins (eg BMP2) and type III TGF‐β1 receptor (TβRIII) expression were markedly up‐regulated in AS‐SLs. However, the roles of these closely related molecules in AS are unknown. Here, we showed that BMP2, TGF‐β1, TβRIII and S100A4 (a fibroblast marker) were abundant in active osteogenic AS‐SL tissues. In vitro, AS‐SL fibroblasts (AS‐SLFs) showed high BMP2, TGF‐β1 and TβRIII expression and auto‐osteogenic capacity. We further evaluated the role of TβRIII in the osteogenesis of normal SLFs. BMP2 combined with TGF‐β1 induced the osteogenesis of TβRIII‐overexpressing SLFs, but the activity was lost in SLFs upon TβRIII knockdown. Moreover, our data suggested that BMP2 combined with TGF‐β1 significantly activated both TGF‐β1/Smad signalling and BMP2/Smad/RUNX2 signalling to induce osteogenesis of SLFs with TβRIII up‐regulation. Furthermore, our multi‐strategy molecular interaction analysis approach indicated that TGF‐β1 presented BMP2 to TβRIII, sequentially facilitating BMP2 recognition by BMPR1A and promoting the osteogenesis of TβRIII‐overexpressing SLFs. Collectively, our results indicate that TGF‐β1 combined with BMP2 may participate in the osteogenic differentiation of AS‐SLF by acting on up‐regulated TβRIII, resulting in excessive activation of both TGF‐β1/Smad and BMP2/BMPR1A/Smad/RUNX2 signalling. [ABSTRACT FROM AUTHOR]

In this paper, a repeated two-stage oligopoly game where two boundedly rational firms produce homogeneous product and apply gradient adjustment mechanism to decide their individual R&D investment is considered. Results concerning the equilibrium in the built model and the stability are discussed. The effects of system parameters on the complex dynamical behaviors of the built game are analyzed. We find that the system can lose stability through a flip bifurcation or a Neimark–Sacker bifurcation. In addition, the coexistence of multiattractors is also discussed using the so-called basin of attraction. At the end of this research, the social welfare of the given duopoly game is also studied. [ABSTRACT FROM AUTHOR]

In this paper, the local and global dynamics of a two-stage Bertrand dynamic duopoly model with R&D spillover are studied. This paper aims to study the complex dynamics of the built model by changing the speed of adjustment and other parameters. Combining analysis tools and numerical techniques, we discuss the stability of the system and calculate the stability conditions at first. Then we infer the dynamic phenomena of the system with different sets of parameters and get some interesting results. If two firms operate under different market environment, the system will exhibit two kinds of chaotic intermittent phenomena. While if they operate in same market environment, the system will exhibit the synchronization and on–off intermittency. Finally, through the study of complex basins and multistability, we see how the number of attractors and the size or shape of the basin will change with the change of parameters. [ABSTRACT FROM AUTHOR]

Based on the oligopoly game theory and the intellectual property rights protection policy, we investigate the complex dynamical behaviors of a mixed duopoly game with quadratic cost. In the new system, a few parameters are improved by considering intellectual property rights protection and the stability conditions of the Nash equilibrium point are discussed in detail. A set of the two-dimensional bifurcation diagrams is demonstrated by using numerical modeling, and these diagrams show abundant complex dynamical behaviors, such as coexistence of attractors, different bifurcation, and fractal structures. These dynamical properties can present the long-run effects of strengthening intellectual property protection. [ABSTRACT FROM AUTHOR]

In this paper, a mixed duopoly dynamic model with bounded rationality is built, where a public-private joint venture and a private enterprise produce homogeneous products and compete in the same market. The purpose of this research is to study the stability and the multistability of the established model. The local stability of all the equilibrium points is discussed by using Jury condition, and the stability region of the Nash equilibrium point has been given. A special fractal structure called "hub of periodicity" has been found in the two-parameter space by numerical simulation. In addition, the phenomena of multistability (also called coexistence of multiple attractors) are also studied using basins of attraction and 1-D bifurcation diagrams with adiabatic initial conditions. We find that there are two different coexistences of multiple attractors. And, the fractal structure of the attracting basin is also analyzed, and the formation mechanisms of "holes" and "contact" bifurcation have been revealed. At last, the long-term profits of the enterprises are studied. We find that some enterprises can even make more profits under a chaotic circumstance. [ABSTRACT FROM AUTHOR]

In this paper, a dynamic two-stage Cournot duopoly game with R&D efforts is built. Then, the local stability of the equilibrium points are discussed, and the stability condition of the Nash equilibrium point is also deduced through Jury criterion. The complex dynamical behaviors of the built model are investigated by numerical simulations. We found that the unique route to chaos is flip bifurcation, and the increase of adjusting speed will cause the system to lose stability and produce more complex dynamic behavior. In addition, we also found the phenomenon of multistability in the given model. Several kinds of coexistence of attractors are shown. In particular, we found that boundary attractors can coexist with internal attractors, which also aggravates the complexity of the system. At last, the chaotic state in the built system has been successfully controlled. [ABSTRACT FROM AUTHOR]