•The robustness assessment framework from multiple perspectives is developed.•A novel cyber-physical network model combined with the AC power flow is proposed.•A novel weak interdependency model ...based on geographical features is constructed.•Optimal improvement strategies are applied to enhance robustness of CPSs.
As technologies are advancing at a rapid pace, the robustness of cyber-physical systems becomes increasingly critical. This paper presents a methodological framework for enhancing the robustness of cyber-physical systems in different failure scenarios. In particular, an AC power flow model and routing scheme are combined to model cyber-physical systems. A weak interdependency is then introduced to accurately characterize cascading failures. Different improvement strategies are finally proposed by comparing their influences on cyber-physical systems from both structural and functional perspectives. For validating the performance of the proposed framework, a case study has been conducted on several simulations. The results have shown that the key node protection strategy can alleviate the impacts of initial failures, while interdependency adjustment strategies can mitigate cascading failures. Specifically, the robustness of using the betweenness-based protection strategy has increased by 60%. The application of the performance degree based interdependency adjustment strategy has still resulted in improving robustness by 24% even if the proportion of node removals is 35%.
Because of the advantages of integrating water pressure blasting and hydraulic fracturing, the use of hydraulic fracturing after water pressure control blasting is a method that is used to fully ...transform the structure of a coal-rock mass by increasing the number and range of hydraulic cracks. An experiment to study hydraulic fracturing after water pressure blasting on cement mortar samples (300 × 300 × 300 mm
3
) was conducted using a large-sized true triaxial hydraulic fracturing experimental system. A traditional hydraulic fracturing experiment was also performed for comparison. The experimental results show that water pressure blasting produces many blasting cracks, and follow-up hydraulic fracturing forces blasting cracks to propagate further and to form numerous multidirectional hydraulic cracks. Four macroscopic main hydraulic cracks in total were noted along the borehole axial and radial directions on the sample surfaces. Axial and radial main failure planes induced by macroscopic main hydraulic cracks split the sample into three big parts. Meanwhile, numerous local hydraulic cracks were formed on the main failure planes, in different directions and of different types. Local hydraulic cracks are mainly of three types: local hydraulic crack bands, local branched hydraulic cracks, and axial layered cracks. Because local hydraulic cracks produce multiple local layered failure planes and lamellar ruptures inside the sample, the integrity of the sample decreases greatly. The formation and propagation process of many multidirectional hydraulic cracks is affected by a combination of water pressure blasting, water pressure of fracturing, and the stress field of the surrounding rock. To a certain degree, the stress field of surrounding rock guides the formation and propagation process of the blasting crack and the follow-up hydraulic crack. Following hydraulic fracturing that has been conducted after water pressure blasting, the integrity of the sample is found to be far lower than after traditional hydraulic fracturing; moreover, both the water injection volume and water injection pressure for hydraulic fracturing after water pressure blasting are much higher than they are for traditional hydraulic fracturing.
Genome editing via CRISPR/Cas9 has become an efficient and reliable way to make precise, targeted changes to the genome of living cells. CXCR4 is a co-receptor for the human immunodeficiency virus ...type 1 (HIV-1) infection and has been considered as an important therapeutic target for AIDS. CXCR4 mediates viral entry into human CD4(+) cells by binding to envelope protein, gp120. Here, we show that human CXCR4 gene is efficiently disrupted by CRISPR/Cas9-mediated genome editing, leading to HIV-1 resistance of human primary CD4(+) T cells. We also show that the Cas9-mediated ablation of CXCR4 demonstrated high specificity and negligible off-target effects without affecting cell division and propagation. The precise and efficient genome editing of CXCR4 will provide a new strategy for therapeutic application against HIV-1 infection.
•A three stage model for analyzing power grid resilience is proposed.•Percolation is used to analyze the accuracy of structural resilience.•Functional model is constructed to study functional ...resilience.•Multiple restorations are compared and the optimal restoration is established.
This paper introduces a novel three-stage analysis framework for investigating power network resilience in the face of failures. First, we introduce network modeling and resilience metrics, followed by an examination of network performance and restoration. The evaluation analysis is validated using IEEE118 and two generated small-world and scale-free networks, each consisting of 300 nodes, respectively. Our evaluation specifically focuses on assessing network resilience from both structural and functional perspectives. Simulation results have demonstrated that degree-based attacks have the most significant impact on reducing the size of the largest network component, while betweenness-based attacks lead to the fastest decrease in network efficiency. These findings have been further supported by percolation theory. Furthermore, the electrical-betweenness recovery strategy demonstrates superior performance compared to other recovery strategies. The proposed approach provides valuable insights for decision-makers in the development of mitigation techniques and optimal protection strategies.
Abstract
Electrocatalytic reduction of carbon monoxide into fuels or chemicals with two or more carbons is very attractive due to their high energy density and economic value. Herein we demonstrate ...the synthesis of a hydrophobic Cu/Cu
2
O sheet catalyst with hydrophobic n-butylamine layer and its application in CO electroreduction. The CO reduction on this catalyst produces two or more carbon products with a Faradaic efficiency of 93.5% and partial current density of 151 mA cm
−2
at the potential of −0.70 V versus a reversible hydrogen electrode. A Faradaic efficiency of 68.8% and partial current density of 111 mA cm
−2
for ethanol were reached, which is very high in comparison to all previous reports of CO
2
/CO electroreduction with a total current density higher than 10 mA cm
−2
. The as-prepared catalyst also showed impressive stability that the activity and selectivity for two or more carbon products could remain even after 100 operating hours. This work opens a way for efficient electrocatalytic conversion of CO
2
/CO to liquid fuels.
Reflood plays an important role in preventing the serious accident process. In this paper, the reflood oxidation performances of Cr-coated Zr-Sn-Nb alloy cladding tubes at 1000 °C, 1100 °C and 1200 ...°C were studied by high-temperature steam oxidation followed by in-situ water quenching. The oxidation kinetics, macroscopic morphology, phase transformation and microstructural evolution were investigated. Cr coating can provide excellent anti-reflood oxidation protection for Zr-Sn-Nb alloy, resulting in an oxidation rate constant of only 1/4–1/7 of that of uncoated Zr-Sn-Nb alloys. However, the cladding tube degraded into fragments due to excessive thermal stress during the in-situ water quenching after reflood oxidation at 1200 °C for 4000 s. After reflood oxidation at 1000 °C and 1100 °C, the most prominent feature of the surface is a porous flocculation structure main due to the formation of volatile products, while after 1200 °C, it is a fine mackerel scale-like structure accompanied by protruding whiskers main owing to Cr3+ rapidly migrates outward to the outer surface via short circuit paths. After oxidation, the cross-section of Cr-coated Zr-Sn-Nb alloys exhibits a multi-layer structure. The thickness of each layer changes approximately linearly with oxidation time. However, due to the redox reaction, compared to that after oxidation for 2000s, the Cr2O3 layer becomes thinner and the residual Cr coating becomes thicker after oxidation at 1200 °C for 4000 s.
Abstract
Background
Neoadjuvant chemoradiotherapy followed by esophagectomy is the standard of care for locally advanced esophageal squamous cell carcinoma (ESCC). However, approximately 30% of ...patients still develop distant metastases and have a high incidence of treatment-related adverse events. Immunotherapy, as a new modality for anti-cancer treatment, has shown promising clinical benefits for patients with ESCC. The synergistic effects of immunotherapy and radiotherapy make their combination promising as neoadjuvant treatment for locally advanced ESCC.
Methods
All participants who meet the inclusion criteria will be enrolled after signing the informed consent form. Patients with thoracic segment esophageal cancer with clinical stage T2–3 N0 M0 or T2–3 N + M0 will be included. A total of 25 patients are to be recruited for the study. Twelve patients will be recruited in phase I, with at least two achieving major pathological response (MPR) before entering phase II. They will be treated with radical surgery within 4–8 weeks after the completion of two cycles of neoadjuvant radiotherapy in combination with camrelizumab according to the study schedule. The primary endpoint is the major pathological remission rate of all per-protocol patients. The secondary endpoints are the R0 resection rate, pathological complete remission rate, and adverse events. The interim analysis will be conducted after 12 patients have been enrolled. The trials will be terminated when more than two treatment-related deaths occur or fewer than five patients have major pathological remission.
Discussion
We designed this prospective single-arm phase II clinical study to evaluate the combination of camrelizumab and standard radiotherapy as preoperative neoadjuvant therapy for patients with resectable ESCC as part of the quest for better treatment options for patients with locally advanced ESCC.
Trial registration
This trial protocol has been registered on the NIH Clinical Trials database (
www.clinicaltrials.gov/
, NCT05176002. Registered on 2022/01/04). The posted information will be updated as needed to reflect protocol amendments and study progress.
Nanometer‐sized magnetic stirring bars containing Pd nanoparticles (denoted as Fe3O4‐NC‐PZS‐Pd) for heterogeneous catalysis in microscopic system were prepared through a facile two‐step process. In ...the hydrogenation of styrene, Fe3O4‐NC‐PZS‐Pd showed an activity similar to that of the commercial Pd/C catalyst, but much better stability. In microscopic catalytic systems, Fe3O4‐NC‐PZS‐Pd can effectively stir the reaction solution within microdrops to accelerate mass transfer, and displays far better catalytic activity than the commercial Pd/C for the hydrogenation of methylene blue in an array of microdroplets. These results suggested that the Fe3O4‐NC‐PZS‐Pd could be used as nanoscale stirring bars in nanoreactors.
Nanostirrers: Nanometer‐sized magnetic stirring bars containing Pd nanoparticles for heterogeneous catalysis in microscopic systems were prepared. They displayed far better catalytic activity than the commercial Pd/C for the hydrogenation of methylene blue in an array of microdroplets.
•FeCoS2/Co4S3/N-doped graphene foam composite was prepared via facile hydrothermal synthesis and chemical vapor deposition process.•The catalyst exhibited remarkable catalytic performance with ...overpotentials of 276 mV for OER and 172 mV for HER at 10 mA·cm−2.•The high catalytic performance was attributed to the Co4S3 and FeCoS2 nanoparticles in-situ grown and evenly distributed on the 3D NGF substrate.•The FeOOH/CoOOH species in situ formed on the surface of FeCoS2/Co4S3/NGF catalyst was the actual catalytic active substance towards OER.
Transition metal sulfide is a kind of electrocatalyst with appropriate cost, high efficiency, and stability. However, introducing additional metal atoms into transition metal complexes to form ternary compounds can more effectively optimize the electronic structure and improve its catalytic performance. In this work, FeCoS2/Co4S3 nanoparticles were groundbreakingly synthesized and loaded on nitrogen-doped graphene foam (NGF) with a 3D network structure by facile hydrothermal synthesis and simple chemical vapor deposition (CVD) process. The transition metal sulfide nanoparticles were uniformly distributed on the surface of NGF substrates. The transition metal sulfide nanostructures can provide a larger surface area, enhance the interaction with the medium, and improve the electrocatalytic performance. The synthesized FeCoS2/Co4S3/NGF catalyst exhibits enhanced HER and OER catalytic performance in 1 M KOH, with overpotentials of 172 mV for the HER and 276 mV for the OER at a current density of 10 mA·cm−2. The performance of the FeCoS2/Co4S3/NGF hybrid catalyst could match the best Fe-Co-S bifunctional electrocatalysts reported in the literature. Strong evidence supports that the FeOOH/CoOOH species in situ formed on the surface of FeCoS2/Co4S3/NGF catalyst was the actual catalytic active substance towards OER. In addition, the Tafel slope, TOF, EIS, and stability test results collaboratively support that Fe-Co-S/NGF shows great potential to be used as a bifunctional electrocatalyst for large-scale overall water electrolysis.
Combined subsegmental surgery (CSS) is considered to be a safe and effective resection modality for early-stage lung cancer. However, there is a lack of a clear definition of the technical difficulty ...classification of this surgical case, as well as a lack of reported analyzes of the learning curve of this technically demanding surgical approach.
We performed a retrospective study of single-port thoracoscopic CSS performed by the same surgeon between April 2016 and September 2019. The combined subsegmental resections were divided into simple and complex groups according to the difference in the number of arteries or bronchi which need to be dissected. The operative time, bleeding and complications were analyzed in both groups. Learning curves were obtained using the cumulative sum (CUSUM) method and divided into different phases to assess changes in the surgical characteristics of the entire case cohort at each phase.
The study included 149 cases, including 79 in the simple group and 70 in the complex group. The median operative time in the two groups was 179 min (IQR, 159-209) and 235 min (IQR, 219-247) p < 0.001, respectively. And the median postoperative drainage was 435 mL (IQR, 279-573) and 476 mL (IQR, 330-750), respectively, with significant differences in postoperative extubation time and postoperative length of stay. According to the CUSUM analysis, the learning curve for the simple group was divided by the inflection point into 3 phases: Phase I, learning phase (1st to 13th operation); Phase II, consolidation phase (14th to 27th operation), and Phase III, experience phase (28th to 79th operation), with differences in operative time, intraoperative bleeding, and length of hospital stay in each phase. The curve inflection points of the learning curve for the complex group were located in the 17th and 44th cases, with significant differences in operative time and postoperative drainage between the stages.
The technical difficulties of the simple group of single-port thoracoscopic CSS could be overcome after 27 cases, while the technical ability of the complex group of CSS to ensure feasible perioperative outcomes was achieved after 44 operations.
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