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To study the relationship between rock mechanical properties and resistivity under deep-underground environmental conditions, a rock resistivity test system, which can realize the simultaneous control of temperature, pressure, seepage, and the chemical environment, was developed; further, a corresponding specimen-sealing method was explored. The system primarily comprises a triaxial system, chemical permeation system, temperature control system, and test control system. The reliability of the system was verified through tests and preliminary experiments. The resistivity of fractured granite specimens under coupling of seepage and temperature and the resistivity of unfrozen and freeze–thawed coals during triaxial compression were tested with this test system. The test results show that the temperature-induced resistivity change is greater at low seepage pressures for fractured granites, and the effect of seepage on rock resistivity is greater at lower temperatures. The resistivity change patterns of unfrozen and freeze–thawed coals during triaxial compression differ quite significantly. The resistivity of unfrozen coal specimens exhibits a decreasing trend in the initial compression stage and then gradually increases with rises in the deviatoric stress. After freezing and thawing, the electrical resistivity of coal decreases during the entire compression process.

The Mott–Schottky effect between Cu nanoclusters and Co nanoclusters on 3D nitrogen-doped porous carbon nanosheet frameworks enhances the catalytic activity of the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER).

Pyridine-N species were induced by CeO2-doping, so that the Fe2N active state was formed through Fe–N elements.

This figure illustrates the electrolysis system at the fish body, power supply at the tail and the cathode (HER)/anode (UOR) catalyzed the designed catalysts with the superhydrophilic and superaerophobic properties at two shark fins.

In literature, the creation of an interface between a highly conductive crystalline phase and an amorphous phase with unsaturated sites has been proven to be an effective strategy in the design of electrocatalysts for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). However, the procedural complexity and limited formation of interfaces have compromised the envisioned effects. In this work, the dense crystalline Fe

A rapid and sensitive high-performance liquid chromatography-high-resolution orbitrap mass spectrometry method was developed for the simultaneous screening of 354 organic poisons and metabolites in blood and urine, including drugs, medications, pesticides, rodenticides, veterinary drugs, alkaloids, and mycotoxins with a multi-toxicant chromatography-mass spectrometry information library. The method and library showed good prospects in clinical poisoning screening and forensic toxicological identification. Blood and urine samples were extracted successively with ethyl acetate in acidic and alkaline conditions; then, the extract was blown to nearly dry by nitrogen gas and redissolved with methanol-aqueous solution (v:v, 50:50), and the dissolved solution was analyzed by LC-MS/MS after filtering. Precursor ions' m/z was set for identification, retention time, fragment ions, and isotopic pattern which were used for confirmation. No interference peaks were found in the blank samples, showing good specificity. The LODs of toxicants in urine and blood were 1.00×10

Although lung cancer treatment strategies have improved in recent years, the 5-year overall survival of non-small cell lung cancer (NSCLC) remains less than 15%. Chemotherapy is considered the most promising option in the comprehensive treatment of NSCLC. Fucoxanthin (FX) is a natural product derived from brown algae and has extensive applications in medicine. Previous studies reported that FX effectively inhibits the growth of NSCLC cells in vitro and in vivo. However, the mechanism underlying the anti-NSCLC effect of FX remains unknown. In this study, NSCLC cell lines and a xenograft nude mouse model were used to examine the anti-NSCLC activities of FX in vitro and in vivo. Network pharmacology analysis and inhibitors or activators of the PI3K/Akt signaling pathway were used to explore the anti-NSCLC mechanisms of FX. The results indicated that FX could inhibit proliferation, migration, and invasion, arrest cell cycle at the G0/G1 phase, and induce apoptosis of NSCLC cells in vitro. Additionally, FX suppressed tumor growth in vivo. The PI3K/Akt signaling pathway was found to be involved in the anti-NSCLC activity of FX. In conclusion, FX inhibits malignant biological behaviors of NSCLC by suppressing the phosphorylation of both PI3K and AKT, and subsequently inactivating PI3K/AKT signaling pathway.

Background The emergence and prevalence of infections with multidrug-resistant organisms (MDROs) pose great challenges for clinical anti-infective therapy. Cardiac surgery is characterized by high surgical difficulty, strict aseptic operation requirements, and long operation time. Previous research data on postoperative MDR bacterial infection are limited. Therefore, it is of great clinical significance to understand the clinical characteristics of adult patients with MDRO infection after cardiac surgery and the risk predictors of infection. Methods The complete medical records of adult patients with MDR bacterial infection after cardiac surgery from January 2018 to October 2021 were collected to understand the clinical characteristics of MDR bacterial infection in a specific environment and to evaluate the risk predictors of MDR bacterial infection after surgery. Results From January 2018 to October 2021, a total of 176 adult patients suffered from MDR bacterial infection after cardiac surgery. A total of 306 strains of MDR bacteria were detected in clinical samples, and 97 patients (55.1%) suffered from multiple bacterial infections. The most common bacterial distribution was Acinetobacter baumannii (114/306, 37.3%). The main clinical manifestations were lower respiratory tract infection (51/176, 29.0%), followed by bloodstream infection (12/176, 6.8%), mediastinal infection (2/176, 1.1%), urinary tract infections (2/176, 1.1%) and skin soft tissue infections (1/176, 0.6%). Preinfection exposure to vancomycin (PConclusion The incidence of MDR bacterial infection is high in adult patients undergoing cardiac surgery, and these organisms are highly resistant to commonly used antibiotics. Therefore, it is of great importance to strengthen perioperative management of inpatients in cardiac surgery, achieve early identification of risk factors for postoperative MDR bacterial infection, and ensure containment of the occurrence and spread of drug-resistant bacterial infection.

Rat body weights in the groups fed different EPA:omega-6 fatty acid ratios.

Table S1 shows the composition of diets fed to F344 rats.

Prostaglandin E2 (PGE2) has been linked to a higher risk of colorectal cancer. PGE2 in colon tissue can be reduced by increasing dietary eicosapentaenoic acid (EPA). The dose-dependent relationships between dietary EPA, serum EPA:arachidonate (AA) ratio, urinary PGE2 metabolites, and colonic eicosanoids were evaluated to develop biomarkers for prediction of colonic PGE2. Male rats were fed diets containing EPA:ω6 fatty acid ratios of 0, 0.1, 0.2, 0.4, or 0.6 for 5 weeks. Increasing the dietary EPA:ω6 fatty acid ratio increased EPA:AA ratios in serum and in the proximal, transverse, and distal colon (P < 0.001). The urinary PGE2 metabolite was reduced (P = 0.006). EPA-rich diets reduced colonic tissue PGE2 concentrations by 58% to 66% and increased PGE3 by 19- to 28-fold. Other AA–derived eicosanoids were reduced by 35% to 83%. The changes were not linear, with the largest changes in eicosanoids observed with the lower doses. A mathematical model predicts colonic tissue eicosanoids from the EPA:AA ratio in serum and the EPA dose. Every 10% increase in serum EPA:AA was associated with a 2% decrease in the (geometric) mean of PGE2 in the distal colon. These mathematical relationships can now be applied to individualized EPA dosing in clinical trials. Cancer Prev Res; 7(10); 1011–22. ©2014 AACR.

Table S2 shows the molar % of fatty acids in the colon at the fed EPA:AA ratios.

The purpose of this paper is to explore the numerical simulation of damage process and results of a new environmentally friendly material, recycled coarse aggregate self-compacting concrete (RCASCC). Random aggregate model of mesoscopic viewpoint was used for the experimental simulation of RCASCC. Results show that the specimens with 50% substitution rate exhibited the best performance among the specimens (i.e., with rates of 25%, 50%, 75%, and 100%). The stress-strain curves after dimensionless treatment were fitted using the uniaxial compressive principal equation of concrete with control parameters a = 0.9 and b = 11, and the fitting degree of the curve was relatively good. Meanwhile, the change process of internal cracking was shown intuitively. The crack expansion process became more obvious in the specimens and beams with a high substitution rate of RCA. The simulation results of the bending process of RCASCC beams analyzed by the concrete damaged plasticity (CDP) model and extended finite element (XFEM) were compared with the test results. Both simulation results validated the applicability of the CDP model and XFEM in the mechanical tests of RCASCC and can provide valuable reference for future research on the mechanical properties of recycled aggregate self-compacting concrete.

The phase transition kinetics of A508-3 steel during continuous cooling were studied by high temperature transition instrument which was based on thermodilatometry in this paper. The microstructures during continuous heating and cooling were also observed. The transition points were determined to be austenite formation temperatures, Ac1 = 757 °C, Ac3 = 823 °C, and martensitic transformation start and final temperatures, Ms = 382 °C, Mf = 222 °C at the cooling rate of 5 °C/s. The curves of Austenite transition fraction and time during continuous heating show a typical S shape. And the Austenite will show a maximum transition rate value at the middle temperature. The volume fraction of new phases translated from Austenite as functions of time and temperature during the cooling process can be obtained using the lever law. The pearlite transitions can occur in high temperature region at cooling rate smaller than 0.1 °C/s. And Bainite can be gotten at a lower temperature region. The S type curves can be used to describe the relationships between the transition volume fraction and time. Increasing the cooling rate enhances the volume fraction of Martensite at the cooling rate ≥5 °C/s. And only Martensite transition can be observed at the cooling rate > 10 °C/s. And Ms and Mf increase with increasing cooling rate. The Martensite transition kinetics equation with changing temperature were obtained. Finally, the continuous cooling transformation curves of A508-3 steel was constructed, which can be used to predict the microstructure and design the heat treatment technologies.

Urea electrolysis is a promising approach to produce hydrogen while simultaneously purifying urea-rich wastewater. In practice, it is highly desirable but still challenging, through the structure construction strategy, to implement a method with controllable synthesis of ultra-thin nanosheet arrays with rich interfaces, and then apply them into the catalysis operations of hydrogen evolution reaction (HER) and urea oxidation reaction (UOR). In this work, the bifunctional electrocatalyst Ni2P/NiCoP nanosheets anchored nickel foam (NF) were prepared with ultra-thin rich interfaces by regulating the Co– and P-doping. The results showed that the elaborated Ni2P/NiCoP/NF electrode delivered the excellent electrocatalytic activities for both UOR and HER operations. Particularly for UOR, it required only a cell voltage of 1.41 V at 100 mA cm−2, which was 400 mV lower than that in the traditional overall water splitting operation.

In this work, NiFe LDH/Ti3C2Tx/Nickel foam (NF) was successfully prepared as a binder-free electrode by depositing NiFe layered double hydroxide (LDH) nanosheets on Ti3C2Tx/NF substrate through electrodeposition approach. The strong electrostatic interactions between the negatively charged surface of MXene and positively charged NF substrate enabled the direct growth of NiFe LDH nanosheets on Ti3C2Tx/NF substrate. As a result, the as-prepared NiFe LDH/Ti3C2Tx/NF electrode exhibited an excellent OER performance, fast catalytic reaction kinetics and good chemical stability. Its overpotential reached 200 mV at a current density of 10 mA cm−2, and the cycling tests suggested a good cycling stability.

An outstanding oxygen reduction reaction (ORR) electrocatalyst is firstly developed deriving from sustainable rice husk (RH) biomass. Benefiting from self-doped Si in RH, the higher proportion of pyridine N, graphite N and expecially Fe-Nx as well as thiophene S contents were produced in Si-Fe/S/N-RH3 in comparison with those of Si-free Fe/S/N-RH3. Consequently, the half-wave potential of 0.89 V and the onset potential of 0.96 V are achieved for Si-Fe/S/N-RH3, outperforming the benchmark electrocatalyst Pt/C and other Fe-based electrocatalysts reported in alkaline media. Furthermore, it is found that the exisentence of self-doped Si can improve the graphitization degree of the catalyst, leading to the long-term stability (larger than 85% retention after 40000 s) and prominent methanol tolerance for Si-Fe/S/N-RH3. In addition, Si-Fe/S/N-RH3 shows a power density of 86.2 mW cm−2 and excellent durability in Zn-air battery. The work highlights the potential to develop sustainable and cost-effective ORR electrocatalysts from waste biomass as the substitute for precious metal catalysts.

SN-CoSn@C NBs as sulfur cathodes for lithium–sulfur batteries. The subnanometric CoSn clusters with single atom and atomic cluster sites were able to boost the chemisorption and electrocatalytic conversion dynamics of polysulfides.

Catalytic conversion of polysulfides is considered to be an important way to improve the kinetics and inhibit the shuttle effect of lithium–sulfur batteries (LSB).

Climate change and its related side effects are generating a demand for innovative ways to enhance desalination performance by adopting cost-effective and energy-efficient membrane materials. Molybdenum disulphide (MoS2), a two-dimensional (2D) material, holds the potential to address the deficiency of the current polymeric reverse osmosis (RO) membrane by maximizing the water-energy nexus. The nanoscale thickness of the MoS2 membrane promises better water permeability benefiting from the small diffusion length of the transport of the molecules while maintaining good chemical and mechanical robustness. Although many advantages have been projected, the experimental realization of such near-atomic thickness has not been fully explored because of the technological difficulties associated with the production. This review first highlights the remarkable combination of the ion’s rejection and permeability properties of the MoS2 membrane by discussing two distinct reported approaches for using MoS2 as a membrane for water desalination. Subsequently, the engineering challenges of the MoS2 membrane scalability for water desalination are discussed. Lastly, the possible opportunities for a well-controlled fabrication process critical to achieving and advancing MoS2 membranes from research laboratories to the industrial-scale application are outlined. We aim to provide a collective understanding of the realization of a high permi-selective MoS2 membrane for water desalination.

Etimicin is a fourth-generation aminoglycoside antibiotic. It has potent activity and low toxicity when employed for the treatment of Gram-negative and Gram-positive bacterial infections. The pharmacokinetics of etimicin in humans have not been elucidated completely. Two liquid chromatography-tandem mass spectrometry (LC-MS/MS) bioanalytical methods, without the use of any ion-pairing reagents, were developed and validated for the quantification of etimicin in human samples of serum and urine. Using a deuterated reagent as the internal standard, analytes in serum and urine samples were extracted by protein precipitation and dilution before LC-MS/MS analysis, respectively. For the two methods, chromatographic separations were undertaken under isocratic elution of water–ammonia solution–acetic acid (96:3.6:0.2, v/v/v) and methanol at 50%:50% and a flow rate of 0.35 ml/min within 5 min. A Waters XTerra MS C18 column (2.1 × 150 mm, 3.5 μm) and a column temperature of 40°C were chosen. A Sciex Qtrap 5500 mass spectrometer equipped with an electrospray ion source was used in both methods under multiple-reaction monitoring in positive-ion mode. The two methods showed good linearity, accuracy, and precision with high recovery and a minimal matrix effect in the range of 50.0–20000 ng/ml for serum samples and 50.0–10000 ng/ml for urine samples, respectively. Carry-over effects were not observed. Etimicin remained stable in human samples of serum or urine under the storage, preparation, and analytical conditions of the two methods. These two simple and reliable methods were applied successfully to a dose-escalation, phase I clinical trial of etimicin in Chinese healthy volunteers after intravenous administration of single and multiple doses. Based on these two methods we ascertained, for the first time, the comprehensive pharmacokinetics of etimicin in humans, which will be used for the exploration of the breakpoint research further.

The mass transfer efficiency and structural stability of the electrode are critical for industrialized water electrolysis operations. Herein, the biomimicry-inspired design of Ni

Using polysulfide electrocatalysts has become an effective strategy to improve the durability of lithium–sulfur batteries (LSBs) by regulating the precipitation and dissolution of lithium sulfide in the electrolyte.

The rational design and controllable synthesis of high-performance energy storage materials are important measures to address the growing demand for energy storage devices.

Cold chain logistics has been playing a more and more crucial role in modern society. As a special professional cold chain logistics, emergency cold chain logistics can provide quality assurance for temperature-sensitive products in emergency situations. Due to the fact that demand is uncertain in emergency situations, the cold chain logistics companies have to deal with the issue of uncertainty. However, there is no literature on the emergency cold chain logistics distribution optimization problem with uncertain demand. This research contributes to solving this problem. To deal with uncertain demand in emergency situations, an emergency cold chain logistics distribution optimization model with time windows is proposed based on scenario analysis. The objectives of the model are to minimize the total cost and shorten the delivery time simultaneously. The model can also optimize product procurement and refrigerated vehicle renting. The multi-scenario optimization model is applied to a Chinese cold chain logistics center to verify its effectiveness.

Steroid 5α-reductase type 2 deficiency (5α-RD2) and androgen insensitivity syndrome (AIS) are difficult to distinguish clinically and biochemically, and adrenal-derived androgens have not been investigated in these conditions using modern methods. The objective of the study was to compare Chinese patients with 5α-RD2, AIS, and healthy men. Sixteen patients with 5α-RD2, 10 patients with AIS, and 39 healthy men were included. Serum androgen profiles were compared in these subjects using liquid chromatography/tandem mass spectrometry (LC-MS/MS). Based on clinical features and laboratory tests, 5α-RD2 and AIS were diagnosed and confirmed by genotyping. Dihydrotestosterone (DHT) and testosterone (T) were both significantly lower in patients with 5α-RD2 than AIS (p < 0.0001). The T/DHT ratio was higher in 5α-RD2 (4.5-88.6) than AIS (13.4-26.7) or healthy men (7.6-40.5). Using LC-MS/MS, a cutoff T/DHT value of 27.3 correctly diagnosed 5α-RD2 versus AIS with sensitivity 93.8% and specificity 100%. Among the adrenal-derived 11-oxygenated androgens, 11β-hydroxyandrostenedione (11OHA4) and 11-ketoandrostenedione (11KA4) were also lower in patients with 5α-RD2 than those of patients with AIS. In contrast, 11β-hydroxytestosterone (11OHT) was higher in 5α-RD2 than AIS. Furthermore, a 11OHT/11OHA4 cutoff value of 0.048 could also distinguish 5α-RD2 from AIS. Thus, both elevated T/DHT values above 27.3 and the unexpected 11-oxygenated androgen profile, with a 11OHT/11OHA4 ratio greater than 0.048, distinguished 5α-RD2 from AIS. These data suggest that the metabolism of both gonadal and adrenal-derived androgens is altered in 5α-RD2.

Waste PET-MOF-Cleanwater: Waste PET-Derived Metal-Organic Framework (MOFs) as Cost-Effective Adsorbents for Removal of Hazardous Elements from Polluted Water / Ren, Jianwei (Editor) [https://orcid.org/0000-0002-6156-0656] ; : UJ Press, 2022, ; ISBN: ; doi:10.36615/9781776419463 Seminar, South Africa; Johannesburg : UJ Press 19-32 (2022). doi:10.36615/9781776419463-02, Published by UJ Press, Johannesburg

This work reviewed the business model of waste PET-to-MOFs from technical feasibility, economic appraisal, commercial viability, and risk assessment. A process model was developed to cover the mass balance, which considered material flows, chemical build-up, and energy requirements. The balance was based on a case of 1 kg/day, and the scalability was proved at a later stage. A financial model was then developed, and the analysis of economic appraisal and commercial viability showed that investing in MOFs will generate roughly a 5% internal rate of return (IRR) on a production capacity of 10 kg daily. Given the fact that these results are positive at a small scale, it is therefore recommended that this investment should proceed. The environmental and opportunity cost that is avoided has not been considered in the financial analysis. This can further strengthen the revenue side of this production. While a return of 5% is not the most attractive, the PET waste that would be redirected to this production contributes to the South African waste management strategy and climate change objectives. In addition, since the South African government bond of ten years yields a return of 8.52% return, this initiative is competitive with a 5% IRR.

Metal-organic frameworks (MOFs)-based atmospheric water harvesting (AWH) has become an interesting research topic to address water scarcity in the arid regions. However, the availability of the cost-effective prototypical MOFs materials poses an actual challenge for their wide applications. In this work, the production of prototypical MOFs from waste PET is recognised as an important stepping-stone towards MOFs-based AWH applications.

Water scarcity and pollution are serious environmental problems and global concerns that affect millions of people. For this reason, there is increasing demand for frequent water quality monitoring. Therefore, there is a need for the development of efficient analytical platforms and methodologies that combine high accuracy, affinity, sensitivity, and selectivity towards various pollutants. Metal-organic frameworks (MOFs) have emerged as promising adsorbents, stationary phases, supports, and active coating for pollutant detection, extraction, sample clean-up, and separation. This chapter summarises the recent advances and trends in the application of MOFs in various analytical methodologies such as solid-phase extraction, solid-phase microextraction, and electrochemical sensors. A brief discussion of the synthesis strategies and their incorporation into various nanomaterials to increase the affinity of the resultant adsorbent towards various analytes is made. The application of MOF-based adsorbents for extraction, preconcentration, separation, and detection of pollutants in water systems is reported.