Study on a Strong Polymer Gel by the Addition of Micron Graphite Oxide Powder and Its Plugging of Fracture.

It is difficult to plug the fracture water channeling of a fractured low-permeability reservoir during water flooding by using the conventional acrylamide polymer gel due to its weak mechanical properties. For this problem, micron graphite powder is added to enhance the comprehensive properties of the acrylamide polymer gel, which can improve the plugging effect of fracture water channeling. The chemical principle of this process is that the hydroxyl and carboxyl groups of the layered micron graphite powder can undergo physicochemical interactions with the amide groups of the polyacrylamide molecule chain. As a rigid structure, the graphite powder can support the flexible skeleton of the original polyacrylamide molecule chain. Through the synergy of the rigid and flexible structures, the viscoelasticity, thermal stability, tensile performance, and plugging ability of the new-type gel can be significantly enhanced. Compared with a single acrylamide gel, after adding 3000 mg/L of micrometer-sized graphite powder, the elastic modulus, the viscous modulus, the phase transition temperature, the breakthrough pressure gradient, the elongation at break, and the tensile stress of the acrylamide gel are all greatly improved. After adding the graphite powder to the polyacrylamide gel, the fracture water channeling can be effectively plugged. The characteristics of the networked water flow channel are obvious during the injected water break through the gel in the fracture. The breakthrough pressure of water flooding is high. The experimental results are an attempt to develop a new gel material for the water plugging of a fractured low-permeability reservoir.

Drop-On-Demand Microdroplet Generation under Charge Injection by Corona Discharge.

In printing, microreactors, and bioassays, the precise control of micrometer-scale droplet generation is essential but challenging, often restricted by the equipment and nozzles used in traditional methods. We introduce a needle-plate electrode corona discharge technique that injects charges into an oil layer, enabling the precise manipulation of droplet polarization and splitting. This method allows for meticulous adjustment of microdroplet formation regarding location, size, and quantity by modulating the discharge voltage, discharge time, and electrode positioning. It enables the immediate initiation and cessation of droplet production, thereby facilitating on-demand droplet generation. Our study on the voltage-dependent droplet stretch coefficient shows that as the voltage increases, the droplets transition from controlled splitting to regular Taylor cone-like ejections, eventually reaching the Rayleigh limit and fully breaking apart. These advancements significantly improve microfluidic droplet manipulation, offering considerable benefits for applications in targeted drug delivery, rapid disease diagnostics, and precise environmental monitoring.

Skin-Inspired All-Natural Biogel for Bioadhesive Interface.

Natural material-based hydrogels are considered ideal candidates for constructing robust bio-interfaces due to their environmentally sustainable nature and biocompatibility. However, these hydrogels often encounter limitations such as weak mechanical strength, low water resistance, and poor ionic conductivity. Here, inspired by the role of natural moisturizing factor (NMF) in skin, a straightforward yet versatile strategy is proposed for fabricating all-natural ionic biogels that exhibit high resilience, ionic conductivity, resistance to dehydration, and complete degradability, without necessitating any chemical modification. A well-balanced combination of gelatin and sodium pyrrolidone carboxylic acid (an NMF compound) gives rise to a significant enhancement in the mechanical strength, ionic conductivity, and water retention capacity of the biogel compared to pure gelatin hydrogel. The biogel manifests temperature-controlled reversible fluid-gel transition properties attributed to the triple-helix junctions of gelatin, which enables in situ gelation on diverse substrates, thereby ensuring conformal contact and dynamic compliance with curved surfaces. Due to its salutary properties, the biogel can serve as an effective and biocompatible interface for high-quality and long-term electrophysiological signal recording. These findings provide a general and scalable approach for designing natural material-based hydrogels with tailored functionalities to meet diverse application needs.

Efficacy and safety of novel immune checkpoint inhibitor-based combinations versus chemotherapy as first-line treatment for patients with extensive-stage small cell lung cancer: A network meta-analysis.

BACKGROUND: Patients with extensive-stage small cell lung cancer (ES-SCLC) have an exceptionally poor prognosis and immune checkpoint inhibitors (ICIs) combined with etoposide-platinum is recommended as standard first-line therapy. However, which combination pattern is the best still remains unknown. This network meta-analysis was performed to compare the efficacy and safety of currently available patterns including an antiangiogenic agent containing regimen and probed into the most appropriate therapy for patients. METHODS: Hazard ratios (HRs) and odds ratios (ORs) were generated using R software. The outcomes of overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and adverse events of grade 3 or higher (grade ≥ 3 adverse events [AEs]) were analyzed. RESULTS: A total of 10 randomized controlled trials (RCTs) involving 5544 patients were included for analysis. Drug combination patterns included adebrelimab, atezolizumab, durvalumab, durvalumab plus tremelimumab, ipilimumab, pembrolizumab, serplulimab, benmelstobart plus anlotinib, tislelizumab, tiragolumab plus atezolizumab and toripalimab in combination with chemotherapy. The novel antiangiogenic agent containing regimen benmelstobart + anlotinib + chemotherapy showed the highest possibility to present the best PFS and OS versus chemotherapy. Compared with ICI plus chemotherapy, it also achieved significantly better PFS and presented a tendency of OS benefit. As for safety and toxicity, patients treated with benmelstobart + anlotinib + chemotherapy and durvalumab + tremelimumab + chemotherapy suffered a higher likelihood of more grade ≥ 3 AEs without unexpected AEs. CONCLUSION: PD-1/PD-L1 inhibitors-based combinations are associated with significant improvement in both PFS and OS for treatment-naïve ES-SCLC patients. Benmelstobart plus anlotinib with chemotherapy (CT) yielded better survival benefit versus CT alone or other ICIs + CT with caution for more adverse effects along with the addition of an antiangiogenic agent.

Digitization and carbon emissions: how does the development of China's digital economy affect carbon intensity?

The digital economy and the pursuit of carbon peak and carbon neutrality have emerged as crucial focal points for China's future development. However, the intricate relationship between the digital economy and carbon intensity remains uncertain. Based on the construction of the digital economy evaluation index system, using panel data for 30 provinces in China from 2011 to 2019, this study estimates the impact of the digital economy development on carbon intensity by adopting the system-generalized method of moments (SYS-GMM) technique. The results show that the digital economy can effectively reduce the carbon intensity. This conclusion was supported by robustness tests. However, the carbon emission reduction effect of the digital economy exhibits heterogeneity with respect to the digital economy dimensions and regions. In addition to digital industrialization and industrial digitization reducing the carbon intensity, the digital economy development carrier has an inverted U-shaped nonlinear relationship with carbon intensity. Additionally, the digital economy has a more obvious inhibitory effect on carbon intensity in the eastern region. Most importantly, besides the mediating effects of technological progress and financial development, this paper finds that the digital economy can increase carbon intensity through human capital accumulation. These conclusions provide a certain scientific basis for the effective implementation of China's digital economy and carbon peak and carbon-neutral development strategy.

A trajectory planning method for a casting sorting robotic arm based on a nature-inspired Genghis Khan shark optimized algorithm.

In order to meet the efficiency and smooth trajectory requirements of the casting sorting robotic arm, we propose a time-optimal trajectory planning method that combines a heuristic algorithm inspired by the behavior of the Genghis Khan shark (GKS) and segmented interpolation polynomials. First, the basic model of the robotic arm was constructed based on the arm parameters, and the workspace is analyzed. A matrix was formed by combining cubic and quintic polynomials using a segmented approach to solve for 14 unknown parameters and plan the trajectory. To enhance the smoothness and efficiency of the trajectory in the joint space, a dynamic nonlinear learning factor was introduced based on the traditional Particle Swarm Optimization (PSO) algorithm. Four different biological behaviors, inspired by GKS, were simulated. Within the premise of time optimality, a target function was set to effectively optimize within the feasible space. Simulation and verification were performed after determining the working tasks of the casting sorting robotic arm. The results demonstrated that the optimized robotic arm achieved a smooth and continuous trajectory velocity, while also optimizing the overall runtime within the given constraints. A comparison was made between the traditional PSO algorithm and an improved PSO algorithm, revealing that the improved algorithm exhibited better convergence. Moreover, the planning approach based on GKS behavior showed a decreased likelihood of getting trapped in local optima, thereby confirming the effectiveness of the proposed algorithm.

Multiomics and blood-based biomarkers of moyamoya disease: protocol of Moyamoya Omics Atlas (MOYAOMICS).

BACKGROUND: Moyamoya disease (MMD) is a rare and complex cerebrovascular disorder characterized by the progressive narrowing of the internal carotid arteries and the formation of compensatory collateral vessels. The etiology of MMD remains enigmatic, making diagnosis and management challenging. The MOYAOMICS project was initiated to investigate the molecular underpinnings of MMD and explore potential diagnostic and therapeutic strategies. METHODS: The MOYAOMICS project employs a multidisciplinary approach, integrating various omics technologies, including genomics, transcriptomics, proteomics, and metabolomics, to comprehensively examine the molecular signatures associated with MMD pathogenesis. Additionally, we will investigate the potential influence of gut microbiota and brain-gut peptides on MMD development, assessing their suitability as targets for therapeutic strategies and dietary interventions. Radiomics, a specialized field in medical imaging, is utilized to analyze neuroimaging data for early detection and characterization of MMD-related brain changes. Deep learning algorithms are employed to differentiate MMD from other conditions, automating the diagnostic process. We also employ single-cellomics and mass cytometry to precisely study cellular heterogeneity in peripheral blood samples from MMD patients. CONCLUSIONS: The MOYAOMICS project represents a significant step toward comprehending MMD's molecular underpinnings. This multidisciplinary approach has the potential to revolutionize early diagnosis, patient stratification, and the development of targeted therapies for MMD. The identification of blood-based biomarkers and the integration of multiple omics data are critical for improving the clinical management of MMD and enhancing patient outcomes for this complex disease.

Research and development of fully enclosed wire-shell support structure technology for deep soft rock roadway based on TRIZ theory.

The TRIZ theory was used to accurately discover the problems to be solved in the design of roadway surrounding rock control technology. This paper tried to solve the complex issue of surrounding rock control in deep roadways from a new perspective. Based on the functional component analysis and causal axis analysis of the problem's primary reason, simultaneously, the surrounding rock control technology was optimized through technical contradiction analysis, physical contradiction analysis, and substance and field model analysis. As a result, a fully enclosed wire-shell support technology was proposed. Finally, taking the typical soft rock roadway engineering of Pansan Coal Mine in Huainan Mining Area, Anhui Province, China, as the engineering background, the engineering application and effect evaluation were completed. This paper provides a reference for controlling the instability of deep soft rock roadways in coal mines. A new idea of optimizing roadway support engineering based on TRIZ theory was proposed.

Study on the Effect of Cations on the Surface Energy of Nano-SiO2 Particles for Oil/Gas Exploration and Development Based on the Density Functional Theory.

Although nano SiO2 exhibits excellent application potential in the field of oil and gas exploration and development, such as drilling fluid, enhanced oil/gas recovery, etc., it is prone to agglomeration and loses its effectiveness due to the action of cations in saline environments of oil and gas reservoirs. Therefore, it is crucial to study the mechanism of the change in energy between nano SiO2 and cations for its industrial application. In this paper, the effect of cations (Na+, K+, Ca2+, and Mg2+) on the surface energy of nano SiO2 particles is investigated from the perspective of molecular motion and electronic change by density functional theory. The results are as follows: Due to the electrostatic interactions, cations can migrate towards the surface of nano SiO2 particles. During the migration process, monovalent cations are almost unaffected by water molecules, and they can be directly adsorbed on the surface by nano SiO2 particles. However, when divalent cations migrate from a distance to the surface of nano SiO2 particles, they can combine with water molecules to create an energy barrier, which can prevent them from moving forward. When divalent cations break through the energy barrier, the electronic kinetic energy between them and nano SiO2 particles changes more strongly, and the electrons carried by them are more likely to break through the edge of the atomic nucleus and undergo charge exchange with nano SiO2 particles. The change in interaction energy is more intense, which can further disrupt the configuration stability of nano SiO2. The interaction energy between cations and nano SiO2 particles mainly comes from electrostatic energy, followed by Van der Waals energy. From the degree of influence of four cations on nano SiO2 particles, the order from small to large is as follows: K+ < Na+ < Mg2+ < Ca2+. The research results can provide a theoretical understanding of the interaction between nano SiO2 particles and cations during the application of nano SiO2 in the field of oil and gas exploration and development.

Clinical Characteristics and Prognoses of Chronic Subdural Hematoma Patients with and without Head Trauma: A Retrospective Comparative Study.

OBJECTIVE: Head trauma is considered as the main cause of chronic subdural hematoma (CSDH). However, many patients develop CSDH with no identified cause. Herein, we conduct a comparative study to investigate the differences in clinical characteristics and surgical outcomes of CSDH patients with and without a history of head trauma. METHODS: We retrospectively reviewed CSDH patients who underwent surgical treatment in our hospital between January 2013 and December 2021. Patients were categorized into a with head trauma (WHT) group and a without head trauma (WOHT) group for comparative analysis. RESULTS: A total of 219 patients were included, 119 (54.3%) cases in the WHT group and 100 (45.7%) cases in the WOHT group. More cancer patients were found in the WOHT group than in the WHT group (P = 0.045). Both at discharge and 6-month follow-up, patients in the WOHT group achieved better clinical outcomes than the WHT group cases (P = 0.025 and 0.034, respectively). Furthermore, ordered multiclass logistic regression analyses indicated that a history of head trauma (odds ratio 2.151, 95% confidence interval 1.052-4.386; P = 0.036) was a risk factor significantly related to the unfavorable outcomes at 6-month follow-ups of CSDH. However, we did not find significant differences between the 2 groups in clinical manifestations, radiological characteristics, postoperative complications, mortality, and recurrence rates. CONCLUSIONS: CSDH patients with a history of head trauma may be more susceptible to unfavorable outcomes; thus, they should be carefully evaluated and given more attention during hospitalization and after discharge.

Gene polymorphism of MTHFR rs1801133 and susceptibility to childhood leukemia in Chinese population.

Background: The purpose of this study is to investigate the genotype and allele distribution of MTHFR rs1801133 in the Chinese population, and to analyze the relationship between gene polymorphism of MTHFR rs1801133 and risk of childhood leukemia. Methods: Blood samples and clinical data of childhood leukemia cases (n=1132) and age-matched healthy controls (n=1053) were collected. Genotypes and allele distribution of MTHFR rs1801133 were detected by PCR-RFLP. Logistic regression model was generated to analyze the relation between MTHFR rs1801133 and susceptibility to childhood leukemia and the chemotherapy response. Results: Age, sex, BMI and family history of tumor were comparable between childhood leukemia cases and healthy controls. Genotypes and allele distribution of MTHFR rs1801133 were remarkably correlated to the risk of childhood leukemia. Genotype risk of MTHFR rs1801133 was parallel to the susceptibility to childhood leukemia. Specifically, compared with people carrying AA allele of MTHFR rs1801133, higher risk of childhood leukemia may occur in people carrying AG+GG allele of MTHFR rs1801133 with a younger age (<15 years) or complete remission from chemotherapy. Conclusions: MTHFR rs1801133 gene polymorphism has a significant correlation with childhood leukemia. It is an important genetic susceptibility gene of childhood leukemia. The reliability of the results requires to be further validated by the high-quality research involving a large sample size in multi-center hospitals.

Bioinspired soft robots for deep-sea exploration.

The deep ocean, Earth's untouched expanse, presents immense challenges for exploration due to its extreme pressure, temperature, and darkness. Unlike traditional marine robots that require specialized metallic vessels for protection, deep-sea species thrive without such cumbersome pressure-resistant designs. Their pressure-adaptive forms, unique propulsion methods, and advanced senses have inspired innovation in designing lightweight, compact soft machines. This perspective addresses challenges, recent strides, and design strategies for bioinspired deep-sea soft robots. Drawing from abyssal life, it explores the actuation, sensing, power, and pressure resilience of multifunctional deep-sea soft robots, offering game-changing solutions for profound exploration and operation in harsh conditions.

Magnetic Anomaly Detection Based on a Compound Tri-Stable Stochastic Resonance System.

In the case of strong background noise, a tri-stable stochastic resonance model has higher noise utilization than a bi-stable stochastic resonance (BSR) model for weak signal detection. However, the problem of severe system parameter coupling in a conventional tri-stable stochastic resonance model leads to difficulty in potential function regulation. In this paper, a new compound tri-stable stochastic resonance (CTSR) model is proposed to address this problem by combining a Gaussian Potential model and the mixed bi-stable model. The weak magnetic anomaly signal detection system consists of the CTSR system and judgment system based on statistical analysis. The system parameters are adjusted by using a quantum genetic algorithm (QGA) to optimize the output signal-to-noise ratio (SNR). The experimental results show that the CTSR system performs better than the traditional tri-stable stochastic resonance (TTSR) system and BSR system. When the input SNR is -8 dB, the detection probability of the CTSR system approaches 80%. Moreover, this detection system not only detects the magnetic anomaly signal but also retains information on the relative motion (heading) of the ferromagnetic target and the magnetic detection device.

Carbon-based nanomaterials mediated adsorption and photodegradation of typical organic contaminants in aqueous fulvic acid solution.

In this work, the formation of carbon-based nanomaterials-fulvic acid (CNMs-FA) composites and their capacities for the adsorption and photodegradation of typical organic contaminants in aqueous solutions were investigated. The results suggested that the formation of CNMs-FA composites was dominated by adsorbing FA on CNMs via the physisorption process, which fit the pseudo-first-order kinetic model and the Langmuir isotherm model. The formed CNMs-FA composites were characterized by using the Brunauer-Emmett-Teller, scanning electron microscopy, and infrared spectroscopy techniques and further applied for examining their effects on the adsorption and photodegradation of selected organic contaminants in aqueous solutions. The adsorption of organic contaminants on CNMs-FA composites is mainly involved in hydrogen bonding and electrostatic interactions between organic contaminants and FA species adhering to CNMs. In addition, the CNMs-FA composites are able to promote the photosensitive degradation of organic contaminants due to the photogenerated reactive species including ROS and CNMs-3FA* under sunlight irradiation. This study provided a deeper and more comprehensive understanding of the environmental behavior of CNMs in real natural surface water and clarified the underlying mechanisms.

Preparation and Properties of Poly(vinyl acetate) Adhesive Modified with Vinyl Versatate.

A series of vinyl versatate (VV10) modified poly(vinyl acetate) adhesive (HVPVAc) were prepared using soap-free emulsion polymerization. Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy was used to characterize the structure of the modified poly(vinyl acetate) latex. The effect of the VV10 content on particle size, viscosity, mechanical properties, and T-peel strength of the modified poly(vinyl acetate) was determined. No absorption peak at 1675-1500 cm-1 in the ATR-FTIR spectrum was observed as a result of the carbon-carbon double bond reacting completely. With the occurrence of -C-O-C and the disappearance of the carbon-carbon double bond in the FTIR spectrum, a more complex structure formed. The structure improves the mechanical properties. Increasing the VV10 content resulted in an increase in particle size from 63 nm to 221 nm, a steady increase in the viscosity of the HVPVAc latex, an increase in tensile strength from 7 MPa to 13.4 MPa, and a decrease in breaking elongation from 1310% to 1004%. As the VV10 content increased from 0 to 30% by weight, the T-peel strength of the HVPVAc adhesive increased from 8.35 N/mm to 18.97 N/mm, indicating improved adhesive performance.

Surgical treatment of chronic subdural hematoma by twist drill craniotomy: A 9-year, single-center experience of 219 cases.

OBJECTIVE: This study aims to assess the safety and efficiency of twist drill craniotomy (TDC) for surgical treatment of chronic subdural hematoma (CSDH) based on a single-center experience of 219 cases performed over nine years. METHODS: We performed a retrospective analysis of CSDH patients who underwent TDC treatment in our hospital between January 2013 and December 2021. Clinical and radiological characteristics, as well as surgical outcomes of the included patients, were reviewed and analyzed. Factors that may affect hematoma recurrence and outcomes were also investigated. RESULTS: A total of 219 patients (186 males and 33 females) were included. Eighteen (8.2%) patients experienced postoperative complications. The in-hospital mortality and recurrence rates in our series were 0.5% (1/219) and 4.1% (9/217), respectively. 91.7% (199/217) of patients achieved favorable outcomes six months after the operation. Duration of drainage catheter (odds ratio [OR] 0.135, 95% confidence interval [CI] 0.017-1.099; P = 0.030) was the only factor significantly related to the recurrence of CSDH. Moreover, brain infarction (OR 5.175, 95% CI 1.417-18.896; P = 0.013), Alzheimer's disease (OR 20.515, 95% CI 1.950-215.840; P = 0.012), and preoperative dysfunction of coagulation (OR 6.509, 95% CI 1.501-28.217; P = 0.012) were markedly associated with unfavorable functional outcomes. CONCLUSION: TDC with irrigation and closed-system drainage is a minimally invasive, simple, safe, and effective surgical technique that can serve as the first-choice for the treatment of CSDH with a low recurrence rate.

Ru(III)-Periodate for High Performance and Selective Degradation of Aqueous Organic Pollutants: Important Role of Ru(V) and Ru(IV).

In this study, Ru(III) ions were utilized to activate periodate (PI) for oxidation of trace organic pollutants (TOPs, e.g., carbamazepine (CBZ)). The Ru(III)/PI system can significantly promote the oxidation of CBZ in a wide initial pH range (3.0-11.0) at 1 µM Ru(III), showing much higher performance than transition metal ions (i.e., Fe(II), Co(II), Zn(II), Fe(III), Cu(II), Ni(II), Mn(II), and Ce(III)) and noble metal ion (i.e., Ag(I), Pd(II), Pt(II), and Ir(III)) activated PI systems. Probe experiments, UV-vis spectra, and X-ray absorption near-edge structure (XANES) spectra confirmed high-valent Ru-oxo species (Ru(V)=O) as the dominant oxidant in the process. Because of the dominant role of Ru(V)=O, the Ru(III)/PI process exhibited a remarkable selectivity and strong anti-interference in the oxidation of TOPs in complex water matrices. The Ru(V)=O species can undertake 1-e- and 2-e- transfer reactions via the catalytic cycles of Ru(V)=O → Ru(IV) → Ru(III) and Ru(V)=O → Ru(III), respectively. The utilization efficiency of PI in the Ru(III)/PI process for the oxidation of TOPs can approach 100% under optimal conditions. PI stoichiometrically transformed into IO3- without production of undesired iodine species (e.g., HOI and I2). This study developed an efficient and environmentally benign advanced oxidation process for rapid removal of TOPs and enriched understandings on reactivity of Ru(V)=O and Ru catalytic cycles.

Comparison of revascularization and conservative treatment for hemorrhagic moyamoya disease in East Asian Countries: a single-center case series and a systematic review with meta-analysis.

Objective: The optimal treatment approach for hemorrhagic moyamoya disease (HMMD) remains a topic of debate, particularly regarding the comparative efficacy of revascularization versus conservative treatment. Our study, which included a single-center case series and a systematic review with meta-analysis, aimed to determine whether surgical revascularization is associated with a significant reduction in postoperative rebleeding, ischemic events, and mortality compared to conservative treatment among East Asian HMMD patients. Methods: We conducted a systematic literature review by searching PubMed, Google Scholar, Wanfang Med Online (WMO), and the China National Knowledge Infrastructure (CNKI). The outcomes of surgical revascularization and conservative treatment, including rebleeding, ischemic events and mortality, were compared. The authors' institutional series of 24 patients were also included and reviewed in the analysis. Results: A total of 19 East Asian studies involving 1,571 patients as well as our institution's retrospective study of 24 patients were included in the study. In the adult patients-only studies, those who underwent revascularization had significantly lower rates of rebleeding, ischemic events, and mortality compared to those who received conservative treatment (13.1% (46/352) vs. 32.4% (82/253), P < 0.00001; 4.0% (5/124) vs. 14.9% (18/121), P = 0.007; and 3.3% (5/153) vs. 12.6% (12/95), P = 0.01, respectively). In the adult/pediatric patients' studies, similar statistical results of rebleeding, ischemic events, and mortality have been obtained (70/588 (11.9%) vs. 103/402 (25.6%), P = 0.003 or <0.0001 in a random or fixed-effects model, respectively; 14/296 (4.7%) vs. 26/183 (14.2%), P = 0.001; and 4.6% (15/328) vs. 18.7% (23/123), P = 0.0001, respectively). Conclusion: The current single-center case series and systematic review with meta-analysis of studies demonstrated that surgical revascularization, including direct, indirect, and a combination of both, significantly reduces rebleeding, ischemic events, and mortality in HMMD patients in the East Asia region. More well-designed studies are warranted to further confirm these findings.

Gibson assembly interposition improves amplification efficiency of long DNA and multifragment overlap extension PCR.

For difficult overlap extension PCR, a Gibson assembly process was inserted between the two PCR rounds to facilitate the formation of complete gene templates at a moderate temperature. That is, after amplifying each DNA fragment, they were preluded by a Gibson assembly process in equal proportion. Then, the assembled mixture was used as a template for the second PCR round. This idea was tested and verified by taking the cloning example of a single and a double site mutation of the retinoblastoma gene. This scheme associates overlap extension PCR with Gibson assembly exquisitely, significantly improving gene amplification efficiency, particularly in the fusion of long genes and multifragments using overlap extension PCR.

Local Fiscal Pressure and Public Health: Evidence from China.

Under the dual challenges of global downward economic pressure and the COVID-19 pandemic, studying the impact of local government fiscal pressure on public health is a meaningful endeavor. First, this paper analyzes the impact of local government fiscal pressure on public health and clarifies its impact mechanisms. Second, by utilizing panel data of 31 Chinese provinces from 2000 to 2020, two-way fixed-effects and mediating-effects models are developed to identify the effects and impact mechanisms of local government fiscal pressure on public health. The results show that local government fiscal pressure can be detrimental to public health through three main mechanisms: reducing public health fiscal expenditures, hindering industrial structure upgrading, and exacerbating environmental pollution. Heterogeneity analysis finds that the negative effects of local government fiscal pressure on public health mainly exist in Central and Western China. Accordingly, three policy implications are proposed: optimizing the fiscal system, accelerating industrial upgrading, and improving the appraisal system of local officers.