High Resistance Research Articles

Organophosphate and carbamate susceptibility profiling of Anopheles gambiae sl. across different ecosystems in southern Benin

Background To overcome the spread of high pyrethroid resistance in the main malaria vectors and malaria disease persistence, it is crucial to look for effective and better resistance management strategies. Understanding the phenotypic profile of Anopheles gambiae sl. against alternatives insecticides like organophosphates and carbamates is crucial. Methods Anopheles larvae and pupae were collected from the breeding sites in rice fields, pineapple crop areas, and peri-urban areas. WHO susceptibility tests were conducted on unfed female mosquitoes aged 3–5 days old. Mosquitoes were exposed to malathion 5%, pirimiphos-methyl 0.25%, and bendiocarb 0.1% using the standard WHO protocol. Polymerase chain reaction (PCR) techniques were used to detect species, kdr and Ace-1 mutations. Results Anopheles gambiae sl. from Sèdjè-Dénou rice field population was resistant to bendiocarb (0.1%) with a mortality rate of 72.2% whereas Anopheles gambiae sl. populations from Zinvié-Dokomey (rice field), Zè-Tozounmè (pineapple field), and Adjagbo (peri-urban area) were suspected to be resistant with mortality rates of 90%, 93.5%, 95.4% respectively. However, all of them were susceptible to organophosphates (malathion and pirimiphos-methyl) with a mortality rate of 100%. PCR assay revealed that 100% of the mosquitoes tested were Anopheles coluzzii. The frequencies of Ace-1R mutation in all Anopheles coluzzii populations tested were low (3–27%). Conclusions Organophosphates (malathion and pirimiphos-methyl) have maintained their efficacy against Anopheles coluzzii populations from Sèdjè-Dénou (rice field), Zè Tozounmè (pineapple field), Zinvié Dokomey (rice field), or Adjagbo (peri-urban area). The good efficacy of these organophosphates against Anopheles coluzzii populations from the southern part of Benin are observed in the current study. The use of pirimiphos-methyl for IRS in this part of the country would be a successful alternative for malaria control in this area.

Within-plant genetic drift to control virus adaptation to host-resistance genes.

Manipulating evolutionary forces imposed by hosts on pathogens like genetic drift and selection could avoid the emergence of virulent pathogens. For instance, increasing genetic drift could decrease the risk of pathogen adaptation through the random fixation of deleterious mutations or the elimination of favorable ones in the pathogen population. However, no experimental proof of this approach is available for a plant-pathogen system. We studied the impact of pepper (Capsicum annuum) lines carrying the same major resistance gene but contrasted genetic backgrounds on the evolution of Potato virus Y (PVY). The pepper lines were chosen for the contrasted levels of genetic drift (inversely related to Ne, the effective population size) they exert on PVY populations, as well as for their contrasted resistance efficiency (inversely related to the initial replicative fitness, Wi, of PVY in these lines). Experimental evolution was performed by serially passaging 64 PVY populations every month on six contrasted pepper lines during seven months. These lines exhibited highly divergent evolutionary trajectories, ranging from viral extinctions to replicative fitness gains. The sequencing of the PVY VPg cistron, where adaptive mutations are likely to occur, allowed linking these replicative fitness gains to parallel adaptive nonsynonymous mutations. Evolutionary trajectories were well explained by the genetic drift imposed by the host. More specifically, Ne, Wi and their synergistic interaction played a major role in the fate of PVY populations. When Ne was low (i.e. strong genetic drift), the final PVY replicative fitness remained close to the initial replicative fitness, whereas when Ne was high (i.e. low genetic drift), the final PVY replicative fitness was high independently of the replicative fitness of the initially inoculated virus. We show that combining a high resistance efficiency (low Wi) and a strong genetic drift (low Ne) is the best solution to increase resistance durability, that is, to avoid virus adaptation on the long term.

Increasing Resistance of Nosocomial and Community-Acquired Escherichia coli in Clinical Samples from Hospitals and Clinics in Sana’a City

Antimicrobial resistance in Escherichia coli presents a global challenge associated with nosocomial infections and increased mortality rates. Understanding resistance profiles is crucial for guiding treatment strategies and ensuring effective antibiotic use. This study aimed to investigate the prevalence and in vitro resistance of E. coli to community-acquired and nosocomial infections. Various clinical samples from 700 patients were cultured on MacConkey’s medium and blood agar. The disk diffusion method was used to determine the antibiotic susceptibility profile of the E. coli isolates following the guidelines of the Clinical and Laboratory Standards Institute (CLSI). Urine, pus, seminal fluid, vaginal swabs, and other body fluids were among the clinical samples analyzed. Of the 112 E. coli isolates, 48.2% were from inpatients and 51.8% were from outpatients, with the majority (66%) isolated from urine samples. Higher resistance levels were observed in the urinary isolates than that in the previously recorded data from the same institutions. Notably, isolates exhibited high resistance to penicillin (98.2%), ampicillin (97.3%), first-generation cephalosporins (90.2%), erythromycin (72.2%), and roxithromycin (95.4%), whereas lower resistance was noted against piperacillin-tazobactam (25.0%), nitrofurantoin (12.5%), and imipenem (9.8%). The overall multidrug resistance rate was 62.5%, with higher rates observed in nosocomial infections (70%) compared to community-acquired isolates (55.6%). However, this difference was not statistically significant (p>0.05). This study underscores the prevalence of E. coli isolates (27.0%) and highlights the concerning level of resistance, particularly to older antibiotics. These findings emphasize the importance of judicious antibiotic use and ongoing surveillance.

A novel oxide ceramic matrix composite with integrated high-temperature EMW absorption and mechanical performance

Oxide ceramic matrix composites (OCMC) are extensively used as thermal structural materials due to good high-temperature resistance, mechanical properties, and oxidation resistance, but they are rarely regarded as electromagnetic wave absorbing materials due to the high resistivity of oxide ceramics/fibers. However, high-performance Al2O3 fiber can be used to design and fabricate OCMC with integrated high-temperature microwave absorbing and mechanical properties by introducing dielectric material into Si-based ceramic matrix. The N610/Si3N4-SiOC composites have the prior mechanical performance because the uniformly distributed Si3N4 matrix made the fiber bear effectively. After that, the Sc2O3 modified SiOC matrix was filled into inter- and intra-fascicular pores forming interfacial polarization, dipole polarization, multiple reflection and scattering to attenuate the incident electromagnetic wave (EMW). The effective absorption bandwidth (EAB) and the minimum reflection coefficient (RCmin) of N610/Si3N4-SiOC(Sc) composites at the thickness of 2.75 mm reach 3.0 GHz and −42 dB in the X band, respectively. In addition, the EMW absorption performance of the composite is relatively stable with EABmax and RCmin of 3.5 GHz and −41 dB in 4–18 GHz at high temperatures. This work provides a strategy for designing and fabricating OCMC with excellent mechanical properties and EMW absorption properties.

Poultry slaughterhouse wastewater as a source of bacterial antimicrobial resistance.

Slaughterhouses produce huge volumes of effluents throughout the production chain that, when discharged untreated into bodies of water, can become a source of environmental contamination. This is particularly worrisome if these effluents are used for irrigation since they increase contamination levels and spread pathogens and resistance determinants to humans and animals. Therefore, in this study, we assessed antimicrobial resistance in bacteria isolated from inlet water, equalization wastewater tanks, treatment plant wastewater, and treated wastewater in slaughterhouse facilities in Rio de Janeiro, Brazil. Four samples were collected at each of the collection points, between June 2021 and July 2022. Following bacterial isolation and identification, the samples were analyzed for antimicrobial resistance using the disk diffusion method to test aminoglycoside, beta-lactam, and fluoroquinolone antimicrobials. A total of 229 bacteria were isolated, with 74 isolates selected from the genera Citrobacter (12), Enterobacter (14), Klebsiella (35), Serratia (5), and Pseudomonas (8). Inlet water had the lowest number of isolates and was the only point with gentamicin-resistant isolates. Raw effluent from the equalization tank showed the highest number of isolated bacteria and resistance levels, followed by treated wastewater and the treatment plant. Across all samples, a high rate of cefoxitin-resistance was observed among the isolated bacteria. Klebsiella pneumoniae stood out as the species that demonstrated the greatest resistance to a variety of antimicrobials. These results highlight the importance of water quality monitoring in mitigating public health and environmental risks and high antimicrobial resistance levels.

Thermoplastic Vulcanizates with an Integration of High Wear-Resistant and Anti-Slip Properties Based on Styrene Ethylene Propylene Styrene Block Copolymer/Styrene Ethylene Butylene Styrene Block Copolymer/Solution-Polymerization Styrene-Butadiene Rubber

Distinguished from traditional vulcanized rubber, which is not reusable, thermoplastic elastomer (TPV) is a material that possesses both the excellent resilience of traditional vulcanized rubber and the recyclability of thermoplastic, and TPVs have been widely studied in both academia and industry because of their outstanding green properties. In this study, new thermoplastic elastomers based on solution polymerized styrene butadiene rubber (SSBR) and thermoplastic elastomers (SEPSs/SEBSs) were prepared by the first dynamic vulcanization process. The high slip resistance and abrasion resistance of SSBR are utilized to improve the poor slip resistance of SEPSs/SEBSs, which provides a direction for the recycling of shoe sole materials. In this paper, the effects of different ratios of the rubber/plastic phase (R/P) on the mechanical properties, rheological properties, micro-morphology, wear resistance, and anti-slip properties of SSBR/TPE TPVs are investigated. The results show that the SSBR/TPE TPVs have good mechanical properties. The tensile strength, tear strength, hardness, and resilience of the TPVs decrease slightly with an increasing R/P ratio. Still, TPVs have a tensile strength of 18.1 MPa when the ratio of R/P is 40/100, and this reaches the performance of the vulcanized rubber sole materials commonly used in the market. In addition, combined with microscopic morphology analysis (SEM), it was found that, with the increase in the R/P ratio, the size of the rubber particles gradually increased, forming a stronger crosslinking network, but the rheological properties of TPVs gradually decreased; crosslinking network enhancement led to the increase in the size of the rubber particles, and the increase in the size of rubber particles made the material in the abrasion of rubber particles fall easily, thus increasing its abrasion volume. Through dynamic mechanical analysis and anti-slip tests, when the R/P ratio was 40/100, the tan δ of TPVs at 0 °C was 0.35, which represents an ordinary vulcanized rubber sole material in the market. The viscoelasticity of TPVs increased with the increase in the R/P ratio, which improved the anti-slip performance of TPVs. SSBR/TPE TPVs are expected to be used in footwear and automotive fields due to their excellent abrasion resistance and anti-slip performance.

SALINITY, VERTICILLIUM WILT TOLERANCE AND GENETIC DIVERSITY ANALYSIS OF UPLAND COTTON GENOTYPES

Cotton is one of the most economically important crops. Screening and selection salt-tolerant cotton genotypes using DNA molecular markers not only introduces tolerant cultivars valuable for hybridization and breeding programs, but also identifies DNA regions implicated in the salinity tolerance mechanism. Screening and selection of cotton genotypes resistant to salinity stress and Verticillium wilt disease using DNA molecular markers not only introduces tolerant cultivars valuable for hybridization and breeding programs, but also identifies DNA regions implicated in the tolerance mechanism. The lowest Disease Severity Index was recorded in AP-317 (0.37) and Tashkent-2 (0.32) varieties. A total of 63 bands were generated based on 12 ISSR primers, 50 of which were polymorphic. The highest PIC value was recorded for UBC841 (0.466). AP-317 of Azerbaijan origin and Kirqizistan-174 of Kyrgyzstan origin were the most distant (0.358) genotypes and at the same time showed high resistance to Verticillium wilt. The obtained results showed that ISSR markers were an effective tool for determining genetic variation and identification of cotton cultivars.

The Arabidopsis thaliana ecotype Ct-1 achieves higher salt tolerance relative to Col-0 via higher tissue retention of K+ and NO3-

Agriculture is vital for global food security, and irrigation is essential for improving crop yields. However, irrigation can pose challenges such as mineral scarcity and salt accumulation in the soil, which negatively impact plant growth and crop productivity. While numerous studies have focused on enhancing plant tolerance to high salinity, research targeting various ecotypes of Arabidopsis thaliana has been relatively limited. In this study, we aimed to identify salt-tolerant ecotypes among the diverse wild types of Arabidopsis thaliana and elucidate their characteristics at the molecular level. As a result, we found that Catania-1 (Ct-1), one of the ecotypes of Arabidopsis, exhibits greater salt tolerance compared to Col-0. Specifically, Ct-1 exhibited less damage from reactive oxygen species (ROS) than Col-0, despite not accumulating antioxidants like anthocyanins. Additionally, Ct-1 accumulated more potassium ions (K+) in its shoots and roots than Col-0 under high salinity, which is crucial for water balance and preventing dehydration. In contrast, Ct-1 plants were observed to accumulate slightly lower levels of Na+ than Col-0 in both root and shoot tissues, regardless of salt treatment. These findings suggest that Ct-1 plants achieve high salinity resistance not by extruding more Na+ than Col-0, but rather by absorbing more K+ or releasing less K+. Ct-1 exhibited higher nitrate (NO3-) levels than Col-0 under high salinity conditions, which is associated with enhanced retention of K+ ions. Additionally, genes involved in NO3- transport and uptake, such as NRT1.5 and NPF2.3, showed higher transcript levels in Ct-1 compared to Col-0 when exposed to high salinity. However, Ct-1 did not demonstrate significantly greater resistance to osmotic stress compared to Col-0. These findings suggest that enhancing plant tolerance to salt stress could involve targeting the cellular processes responsible for regulating the transport of NO3- and K+. Overall, our study sheds light on the mechanisms of plant salinity tolerance, emphasizing the importance of K+ and NO3- transport in crop improvement and food security in regions facing salinity stress.

Fundamental structural study of hexagonal boron nitride (h-BN) and boron nitride nanotube (BNNT) at low and high temperatures

The molecular structure stability at low and high temperature is important for an industrial application. The boron nitride-based materials, such as hexagonal boron nitride (h-BN) and boron nitride nanotubes (BNNTs), have been interested due to their high oxidation resistance and thermal stability. In this study, ex-situ and in-situ characterization techniques (e.g., Raman spectroscopy, X-ray Diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR)) were applied to investigate the structural change of BNNT and h-BN at high (up to 800 °C) and low (down to -50 °C) temperatures. The Raman spectroscopy results showed that at high temperatures (800 °C), h-BN exhibited a significant red shift under both inert and oxidizing conditions, while BNNT showed no peak shift, indicating its more stable structural resistance compared to h-BN. Both h-BN and BNNT showed no peak shift after cooling to low temperatures (-50 °C). Stability of h-BN and BNNT up to a high temperature of 800 °C was revealed from the thermogravimetric analysis (TGA) and FTIR spectroscopy results. The FTIR results also indicate that under oxidizing conditions, heating h-BN results in the formation of more hydroxyl groups compared to BNNT. The in-situ XRD results showed a greater magnitude of lower 2θ shift with increasing temperatures for h-BN compared to BNNT. Additionally, there was a more significant increase in FWHM values with respect to temperatures for h-BN than BNNT regardless of the sample under inert or oxidizing conditions. The characterization results from this study indicate that BN-based materials, especially BNNT, are suitable candidates for high temperature chemical reaction applications.

Improving polymer electrolyte membrane fuel cell performance and preventing flooding by exciting gas flow

Effective water management is necessary to prevent the performance degradation of polymer electrolyte membrane fuel cells (PEMFCs). In this study, acoustic pressure waves (AWs) are superimposed on an oxygen gas flow passing through a cathode to evaluate its potential to mitigate the flooding issue in flow channels. The goal is to expedite droplet removal by exciting droplets at frequencies close to their natural frequency. In-situ experiments are conducted to investigate the influence of AWs on two-phase flows in the cathode channel and the corresponding PEMFC performance. When AWs are applied, the frequency of water discharge from the cathode channel increases, and reduces the internal accumulated water, resulting in the pressure drop decreases. The internal flooding is also decreased, resulting in the reduction of the high frequency resistance attributed to decreased contact resistance. The external excitation improves the PEMFC performance owing to the effective and frequent water discharge induced by the increase in the local inertial force related to the droplet oscillation. The water management method propose in this study is considered to be an efficient method not only for PEMFC systems but also for other systems requiring water management.

Acid sites-CeOx doping CrZrCeOx catalyst with high SO2 resistance for marine SCR application: Surface analysis and mechanism study

This paper mainly talked about acid sites-CeOx doping CrZrCeOx catalyst with high SO2 resistance for marine NH3– SCR (selective catalytic reduction). The NO removal efficiency of the Cr:Zr:Ce = 8:2:1 catalyst reached 90 % with 500 ppm SO2 and 85 % with 1000 ppm SO2 for 20 h, respectively. It was inferred that the main roles of CeOx species were acid sites but not redox sites. CeOx addition promoted the SCR performance and SO2 resistance, which significantly changed the adsorbed species on the surface. CeOx acted as sacrifice sites to protect CrOx actives sites through reducing the combination of Cr and sulfates. The Cr:Zr:Ce = 8:2:1 catalyst followed Langmuir-Hinshelwood (L-H) mechanism and the reaction process was derived in this paper. It indicated that the Cr:Zr:Ce = 8:2:1 catalyst would be a promising marine SCR catalyst with good SO2 resistance in the future.

Comparisons between In-Check DIAL® and PF810® in evaluation and training inspiratory capacity for using dry powder inhalers

BackgroundDry powder inhalers (DPIs) rely on both internal resistance and patients’ inspiratory capacity for effective operation. Optimal inspiratory technique is crucial for DPI users. This study assessed the accuracy and repeatability of two available devices, PF810® and In-Check DIAL®, and analyzed their measurement errors and consistency in detecting inspiratory capacity.MethodsThe accuracy and repeatability of peak inspiratory flow (PIF) and forced inspiratory vital capacity (FIVC) against various internal resistances of the two devices were assessed using standard waveforms generated by a breathing simulator. The agreement of PIF measurements between the two devices in healthy volunteers and chronic obstructive pulmonary disease (COPD) patients was analyzed with the intraclass correlation coefficient and Bland–Altman graphical analysis.ResultsPF810® showed great accuracy and repeatability in measuring PIF, except for square waveforms at the lowest flow rate (20 L/min). In-Check DIAL® exhibited poor accuracy against high resistance levels. In scenarios with no resistance, In-Check DIAL® had significantly smaller measurement errors than PF810®, but larger errors against high resistance levels. The two devices showed excellent agreement (ICC > 0.80, P < 0.05), except for healthy volunteers against medium to high resistance (R3-R5) where the ICC was insignificant. Bland–Altman plots indicated small disagreements between the two devices for both healthy volunteers and COPD patients.ConclusionsIn-Check DIAL® exhibited poor accuracy and larger measurement errors than PF810® when detecting PIFs against higher internal resistances. However, its good performance against lower internal resistances, along with its cost-effectiveness and convenience made it appropriate for primary care. PF810® showed good accuracy and repeatability and could detect additional parameters of inspiratory capacity beyond PIF, though required further studies to confirm its clinical benefits.

1H NMR analysis of metabolites from leaf tissue of resistant and susceptible oil palm breeding materials against Ganoderma boninense.

Breeding for oil palm resistance against basal stem rot caused by Ganoderma boninense is challenging and time-consuming. Advanced oil palm gene pools are very limited, hence it is assumed that parental palms have experienced genetic drift and lost their resistance genes against Ganoderma. High-throughput selection criteria should be developed. Metabolomic analysis using 1H nuclear magnetic resonance (NMR) spectroscopy is easy, and the resulting metabolite can be used as a diagnostic tool for detecting disease in various host-pathogen combinations. The objective of this study was to identify metabolite variations in Dura (D) and Pisifera (P) parental palms with different resistance levels against Ganoderma and moderately resistant DxP using 1H NMR analysis. Leaf tissues of seven different oil palm categories consisting of: resistant, moderate, and susceptible Dura (D); moderate and susceptible Pisifera (P); resistant Tenera/Pisifera (T/P) parental palms; and moderately resistant DxP variety progenies, were sampled and their metabolites were determined using NMR spectroscopy. Twenty-nine types of metabolites were identified, and most of the metabolites fall in the monosaccharides, amino acids, and fatty acids compound classes. The PCA, PLS-DA, and heatmap multivariate analysis indicated two identified groups of resistance based on their metabolites. The first group consisted of resistant T/P, moderate P, resistant D, and moderately resistant DxP. In contrast, the second group consisted of susceptible P, moderate D, and susceptible D. Glycerol and ascorbic acid were detected as biomarker candidates by OPLS-DA to differentiate moderately resistant DxP from susceptible D and P. The pathway analysis suggested that glycine, serine, and threonine metabolism and taurine and hypotaurine metabolism were involved in the oil palm defense mechanism against Ganoderma. A metabolomic study with 1H NMR was able to describe the metabolite composition that could differentiate the characteristics of oil palm resistance against basal stem rot (BSR) caused by G. boninense. These metabolites revealed in this study have enormous potential to become support tools for breeding new oil palm varieties with higher resistance against BSR.

Bayesian-optimized LSTM-DWT approach for reliable fault detection in MMC-based HVDC systems

As Europe integrates more renewable energy resources, notably offshore wind power, into its super meshed grid, the demand for reliable long-distance High Voltage Direct Current (HVDC) transmission systems has surged. This paper addresses the intricacies of HVDC systems built upon Modular Multi-Level Converters (MMCs), especially concerning the rapid rise of DC fault currents. We propose a novel fault identification and classification for DC transmission lines only by employing Long Short-Term Memory (LSTM) networks integrated with Discrete Wavelet Transform (DWT) for feature extraction. Our LSTM-based algorithm operates effectively under challenging environmental conditions, ensuring high fault resistance detection. A unique three-level relay system with multiple time windows (1 ms, 1.5 ms, and 2 ms) ensures accurate fault detection over large distances. Bayesian Optimization is employed for hyperparameter tuning, streamlining the model’s training process. The study shows that our proposed framework exhibits 100% resilience against external faults and disturbances, achieving an average recognition accuracy rate of 99.04% in diverse testing scenarios. Unlike traditional schemes that rely on multiple manual thresholds, our approach utilizes a single intelligently tuned model to detect faults up to 480 ohms, enhancing the efficiency and robustness of DC grid protection.

Impact of dopants on electrical conductivity of proton-conducting SrHfO3 perovskite

For reliable long-term operation of solid oxide electrochemical devices for the hydrogen energy system, an electrolyte with high ionic conductivity and excellent chemical stability is required. SrHfO3-based perovskites are known for their high chemical resistance; however, their ionic conductivity must be increased. In the present research, the effect of doping with yttrium and ytterbium on the electrical properties of strontium hafnate was studied for the first time. The crystal structure, solubility limit of the dopants, morphology and electrical properties of SrHf1-xMxO3-δ (M = Y, Yb) materials were investigated by the X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, direct current four-probe technique, and impedance spectroscopy. The solubility limits of Y and Yb in SrHfO3 were found to lie slightly below x = 0.10. It was revealed that yttrium doping is more favorable for the grain growth and densification of ceramics. A comparative analysis of the influence of dopant type (Y, Yb and Sc) and concentration on the electrical properties of SrHfO3 is provided.

High-Strength Controllable Resin Plugging Agent and Its Performance Evaluation for Fractured Formation

Lost circulation is a common and complicated situation in drilling engineering. Serious lost circulation may lead to pressure drop in the well, affect normal drilling operations, and even cause wellbore instability, formation fluid flooding into the wellbore, and blowout. Therefore, appropriate preventive and treatment measures need to be taken to ensure the safe and smooth operation of drilling operations. So, it is necessary to conduct in-depth research on the development and performance of the plugging materials. In this study, urea formaldehyde resin with high temperature resistance and strength was used as the main raw material, and the curing conditions were optimized and adjusted by adding a variety of additives. The curing time, compressive strength, temperature resistance, and other key performance indexes of the resin plugging agent were studied, and a resin plugging agent system with excellent plugging performance was prepared. The formula is as follows: 25% urea formaldehyde resin +1% betaine +1% silane coupling agent KH-570 + 3% ammonium chloride +1% hexamethylenetetramine +1% sodium carboxymethyl cellulose. The optimal curing temperature is between 60 and 80 °C, with a controllable curing time of 1–3 h. Experimental studies examined the rheological and curing properties of the resin plugging agent system. The results showed that the viscosity of the high-strength curable resin system before curing remained stable with increasing shear rates. Additionally, the storage modulus and loss modulus of the resin solutions increased with shear stress, with the loss modulus being greater than the storage modulus, indicating a viscous fluid. The study also investigated the effect of different salt ion concentrations on the curing effect of the resin plugging system. The results showed that formation water containing Na+ at concentrations between 500 mg/L and 10,000 mg/L increased the resin’s curing strength and reduced curing time. However, excessively high concentrations at lower temperatures reduced the curing strength. Formation water containing Ca2+ increased the curing time of the resin plugging system and significantly impacted the curing strength, reducing it to some extent. Moreover, the high-strength curable resin plugging agent system can effectively stay in various fracture types (parallel, wedge-shaped) and different fracture sizes, forming a high-strength consolidation under certain temperature conditions for effective plugging. In wedge-shaped fractures with a width of 10 mm, the breakthrough pressure of the high-strength curable resin plugging agent system reached 8.1 MPa. As the fracture width decreases, the breakthrough pressure increases, reaching 9.98 MPa in wedge-shaped fractures with an outlet fracture width of 3 mm, forming a high-strength plugging layer. This research provides new ideas and methods for solving drilling fluid loss in fractured loss zones and has certain application and promotion value.

Investigation of wear characteristics of granite dust &amp; coconut shell ash reinforced aluminum metal matrix composite using design of experiment

Abstract Context: Recently, one of the most important issue faced by all nations is a waste management. Therefore, it is essential to search for creative solutions to waste reduction, reuse, and recycling. This can be accomplished by adding waste materials to composite materials as a reinforcements. Reusing waste materials enhances the characteristics of existing materials, while also helping the environment by solving the disposal problem. Purpose: The main aim of this paper is to study the wear characteristics of hybrid aluminum metal matrix composite reinforced with coconut shell ash (CSA) and granite dust. Methodology: The hybrid composite samples were manufactured using stir casting by reinforcing CSA (ranging from 0 wt.% to 12 wt.%) and granite dust (maintained at 2 wt. percent) in Al6061 alloy. SEM and EDAX analysis were performed to investigate the microstructure and elemental composition. The wear characteristics of the hybrid composites were determined via pin-on-disc tests. Finally, the Taguchi design of experiment was performed on the specimen having the best wear characteristics by selecting the L27 orthogonal array and identified the influence of process variables on the wear rate. Results: The results of the pin-on-disc experiment showed that the wear rate decreased with increasing CSA %. The Taguchi analysis prooved that the sliding distance has a greater impact on the wear rate than the other parameters. Conclusion: The hybrid composite composed of 02 wt. % granite dust, &amp; 12 wt. % CSA indicates a lower wear rate (56.25%) when compared to matrix alloy. This material can be a superior substitute where high wear resistance is required.

Preparation of PVDF@TiO2 hybrid membrane and the research of the “hydration layer & rigid layer obstruction-electrostatic coalescence” anti-oil fouling mechanism

In this study, the 3-Aminopropyltriethoxysilane (APTES) was first grafted onto TiO2 nanoparticles (APTES-TiO2 nanoparticles), which were then introduced the membrane surface by reacting with anhydride on the membrane surface and Schiff base reaction with the PEI-TA. There are two types of hollow fiber hybrid membranes with varying nanoparticle distributions were constructed. The influence of hybrid mode on the ability of anti-oil fouling was researched. The results indicated that the PVDF@TiO2 hybrid membrane has a flux recovery rate of 96.68 % and a total flux decline rate of 15.52 %, indicating a good anti-emulsified oil fouling performance. By characterizing the anti-oil droplets adhesion, water-binding capacity, surface charge of membrane and concentrate system coacervate size, the coalescence ability of the hybrid membrane to the oil droplets and the spreading behavior of oil droplets on the surface were uncovered. Ultimately, the anti-fouling mechanism “hydration layer &rigid layer obstruction-electrostatic coalescence” was proposed, which can reasonably explain the weakness of the interplay between the membrane surface and oil droplets, thus slowing down the attaching and spreading of emulsified oil droplets. This study laid the foundation for developing hybrid membranes with high resistance to emulsified oil fouling ability. The proposed anti-fouling mechanism can provide new ideas for the efficient purification of oily wastewater.

A Transcriptome Analysis of Poncirus trifoliata, an Aurantioideae Species Tolerant to Asian Citrus Psyllid, Has Identified Potential Genes and Events Associated with Psyllid Resistance

Citrus huanglongbing (HLB) is a devastating disease for citrus production, largely caused by the Asian citrus psyllid (ACP). Poncirus trifoliata exhibits high resistance to ACP; however, this resistance is weakened when C. sinensis is co-cultivated. This study aimed to identify the differentially expressed genes (DEGs) during ACP feeding and to uncover potential ACP resistance genes in P. trifoliata. In comparison to independent cultivation, 1247 and 205 DEGs were identified in P. trifoliata when co-cultivated with C. sinensis after 7 and 14 days, respectively. Analysis of enriched Gene Ontology categories revealed that DEGs were significantly associated with the cell wall, glucometabolic activities, and secondary metabolites. Additionally, these genes were found to be involved in phytohormone signaling, cell wall metabolism, redox state homeostasis, and secondary metabolites, as well as a number of transcription factor genes (TFs). Furthermore, we examined the impact of the ACP feeding factor on the gene expression patterns in P. trifoliata. Results showed an increase in the JA signaling pathway and various TFs. The RNA-seq results were verified using reverse transcription quantitative PCR. Our findings shed light on the molecular basis of ACP resistance in P. trifoliata and identified potential genes associated with this resistance.

Screening of the Lipid-Lowering Probiotic Lactiplantibacillus Plantarum SDJ09 and its Anti-Obesity Mechanism.

In this study, 39 strains of lactic acid bacteria were screened from several fermented foods. Based on the evaluation of functional and prebiotic properties, Lactiplantibacillus plantarum SDJ09 was selected as a promising candidate. It gave a 48.16% cholesterol reduction and 33.73% pancreatic lipase inhibition in cells; exhibited high resistance to acid, bile salts, and gastrointestinal fluid; and had strong antibacterial activity and high adhesion capabilities. More importantly, the lipid-lowering effect of L. plantarum SDJ09 was also investigated using 3T3-L1 mature adipocytes and HepG2 nonalcoholic fatty liver disease models. L. plantarum SDJ09 effectively decreased triglyceride accumulation by more than 50% in both cell models, in which the expression of PPARγ, C/EBPα, aP2, and LPL in 3T3-L1 cells was significantly downregulated by L. plantarum SDJ09. L. plantarum SDJ09 also improved lipid metabolism by downregulating the expression of HMGCR, SREBP-1c, ACC, and FAS and upregulating the expression of CYP7A1 in HepG2 nonalcoholic steatohepatitis cells. Therefore, L. plantarum SDJ09 has the potential to effectively decrease obesity and non-alcoholic fatty liver disease (NAFLD) by inhibiting lipid accumulation, providing a prospective probiotic agent for anti-obesity.