Resistance Ability Research Articles

In Vitro Antibiofilm Activity of Fosfomycin Alone and in Combination with Other Antibiotics against Multidrug-Resistant and Extensively Drug-Resistant Pseudomonas aeruginosa.

Due to its rapid resistance development and ability to form biofilms, treatment of Pseudomonas aeruginosa infections is becoming more complicated by the day. Drug combinations may help reduce both resistance and biofilm formation. Using the microtiter plate assay, we investigated the in vitro inhibition of biofilm formation and the disruption of preformed biofilms in multidrug-resistant and extensively drug-resistant clinical isolates of P. aeruginosa in the presence of peak plasma levels of eight antipseudomonal antibiotics alone and in combination with fosfomycin: ceftazidime, piperacillin/tazobactam, cefepime, imipenem, gentamicin, amikacin, ciprofloxacin and colistin. Combination therapy was significantly superior to monotherapy in its inhibition of biofilm formation. The highest inhibition rates were observed for combinations with colistin, cefepime and ceftazidime. Our results support fosfomycin combination therapy as an enhanced prophylactic option. Moreover, combinations with β-lactam antibiotics and colistin demonstrated a more potent inhibition effect on biofilm formation than protein synthesis inhibitors.

Experimental and simulation studies on the waterproofing performance of anchored sealing gasket for shield tunnel lining

Anchored sealing gasket can be prefabricated together with prefabricated segment in the prefabrication factory, which can significantly improve the on-site construction convenience and waterproofing performance of shield tunnel segments. This paper proposed a novel anchored sealing gasket with a closed bottom and a symmetric pair of anchored feet on both sides, and the mechanical properties, waterproofing performance, and leakage mechanism of the gasket was investigated by experimental and numerical simulation methods. Test results show that for traditional sealing gasket, leakage occurs at the contact surface between the sealing gasket and the segment, while for anchored sealing gasket, leakage occurs only at the contact surface between the sealing gaskets, which indicates that the anchored sealing gasket feet can effectively prevent leakage between the sealing gasket and the shield segment. Compared with the traditional sealing gasket, the waterproofing ability of the anchored sealing gasket under the same working conditions is increased by 114%. The dynamic simulation of the waterproofing behavior of the anchored sealing gasket, considering the effect of water pressure, was carried out based on the flow-solid coupling model established by the Coupled Euler-Lagrangian (CEL) method. It was found that the waterproofing behavior of the anchored sealing gasket can be divided into four stages: the segment compression stage, the water compression stage, the water wedge stage, and the water breakthrough stage. The water resistance ability between the anchored sealing gasket and the segment is much higher than between the sealing gaskets. The anchor feet can prevent leakage at the interface between the gasket and the segment effectively. In addition, it was found that the test value of the waterproofing capacity of the anchored sealing gasket was close to the peak value of the maximum contact stress between the sealing gaskets during the water wedging stage, and this peak value can be used as a prediction method for the waterproofing capacity of the anchored sealing gasket to investigate the effect of joint deformation on waterproofing capacity. Finally, based on the experimental and simulation results, the waterproofing mechanism of the anchored sealing gasket was revealed, providing a reference for the waterproofing design of anchored sealing gaskets for prefabricated underground structures joints in the future.

Multifaceted Plant Growth Promoting Traits and Abiotic Stress Resistance Abilities Exhibited by Chrysanthemum Rhizobacteria

Plant growth-promoting rhizobacteria (PGPR) boost plant growth and agricultural sustainability in an ecologically friendly way. The cultivation of chrysanthemum, a globally significant flower crop, has relied heavily on substantial agrochemical inputs that have detrimental impact on the environment. To assess the potential of chrysanthemum rhizobacteria to reduce this reliance, bacterial strains were retrieved from the plant rhizosphere and subjected to an assessment of various plant growth-promoting traits. Out of the 34 rhizobacterial isolates, 21 demonstrated the production of the plant growth hormone auxin, 21 had phosphate solubilization ability, 22 were capable of nitrogen fixation, and 21 could produce ammonia. Based on these findings, seven preeminent PGPR strains, characterized by multifaceted plant growth-promoting traits, were selected for subsequent studies and identified as species belonging to Acinetobacter, Bacillus, Pantoea, Serratia and Staphylococcus. The selected strains were systematically analyzed for their capacity to endure an array of abiotic stresses. A majority of these strains demonstrated adaptation under osmotic stress ranging from -0.15 to -0.49 MPa, temperatures of 20°C and 30°C, and salt stress within the range of 3 to 7% NaCl, which suggests their potential to promote plant growth across diverse environmental conditions. Additionally, the secretion of hydrolytic enzymes such as protease, pectinase and amylase was examined, and only the Staphylococcus hominis PGPR-12 strain demonstrated the ability to produce all three extracellular hydrolases. These findings underscore the potential application of multiple isolates possessing promising plant-probiotic properties to enhance plant growth across various conditions, thereby necessitating further exploration through pot and field assays.

Soil drought stress and high-temperature effects on photosystem II in different juvenile spruce provenances

Abstract With prolonged periods of drought and temperature extremes becoming more frequent, the stress on Norway spruce has increased, as its ecological optimum is in colder and more humid environments. However, it is a tree species with a good adaptability, due to its great geographic and intraspecific variability. In this study, we tested the sensitivity of chlorophyll a fluorescence tools for the early detection of drought and heat stress, as well as their combined effect, in four Slovak Carpathian provenances, under controlled laboratory conditions. Responses in photosynthetic parameters of fast and slow (light response curves) kinetics of chlorophyll a fluorescence were analysed in spruce seedlings under four treatments: control, drought, heat, and combined drought + heat. Heat and drought + heat stresses led to the decrease of photosynthetic efficiency to a greater extent than in the case of only individual drought stress. The less sensitive parameter impacted by the stresses was the maximum quantum yield of PSII photochemistry (Fv/Fm), while the more sensitive parameters were: the performance index based on absorption of light energy (PIABS), the effective quantum yield of the PSII (ΦPSII), and the coefficients of non-photochemical fluorescence quenching (NPQ, qN). The significant variability in responses of individual provenances was also observed. Seedlings from two studied provenances responded better to these abiotic stresses (Pa-680 and Pa-1500); however, Pa-1500 provenance from the highest altitude showed the best ability of resistance to soil drought stress, as well as to high temperature effect. This rapid screening of photosystems II efficiency showed the importance of the selection of more resistant populations to concurrent stresses as one of the measures to mitigate climate change impacts.

A facile approach to prepare Cu(I) based adsorbents for selective CO adsorption with excellent oxidation resistance ability

A facile approach to prepare Cu(I) based adsorbents for selective CO adsorption with excellent oxidation resistance ability

The Impact of the Different Types of Dance Cheerleading on the Physical Aspect, Adaptive Ability and Level of Resilience of Middle School Students

The purpose of this study is to compare the effects of different types of dance cheerleading on the physical fitness and health level of junior high school students in Kaili City, and to explore the relationship between its effects on physical fitness, adaptive ability and level of resistance to frustration. The subjects of the investigation included students in the Street Dance Cheerleading group, Jazz Cheerleading group and Flower Ball Cheerleading group, participating in the "Physical Education and Health" course. Through the research design of description-comparison-correlation, the data were collected by questionnaire method and analyzed using mathematical statistics software. The results showed that different types of cheerleading had a significant effect on secondary school students' physical ability, adaptability and level of resistance to frustration. It is recommended that schools and educational organizations should strengthen the promotion of cheerleading activities while paying attention to the differences in gender and types of cheerleading in order to improve the overall physical fitness of students and develop their teamwork spirit.

Investigation on the Preparation and Performances of Epoxy-Modified Asphalt Binder and Its Mixtures.

Epoxy-modified asphalt binder has been widely used in steel deck pavement due to its excellent properties and it is a potential candidate for long life pavements. However, its short reserve time limits its widespread application in pavement engineering. Therefore, this work developed a novel epoxy-modified asphalt binder composed of a laboratory-made curing agent as a solution. Firstly, optimization of preparation temperature of this new material was studied to balance the requirements of enough construction time and the material strength and elongation. The epoxy-modified asphalt binder, prepared at the optimal temperature of 140 °C, had a reserve time exceeding 120 min, whereas the tensile strength and the elongation at failure were 2.22 MPa and 216%, respectively, which satisfied the standard requirements of paving epoxy material well. Secondly, the asphalt mixture property tests demonstrate excellent high-temperature rutting resistance, water stability and low-temperature anti-cracking ability. Additionally, the compatibility and colloidal stability of this epoxy-modified asphalt binder were analyzed in terms of microphase structure. The uniform microphase distribution of this binder showed by the laser confocal microscope observation in both short-term aging case and long-term aging case, indicates the great compatibility between asphalt and epoxy resin during paving process and service life. Furthermore, fatigue tests were conducted to evaluate the long-term durability. The fatigue life of epoxy-modified asphalt mixtures increased by 435%, 427%, 342%, and 276% under the stress ratios of 0.3, 0.4, 0.5, and 0.6, respectively, compared to those of SBS-modified asphalt mixtures. All these results indicate that the new epoxy-modified asphalt material is promising for applications in pavement engineering, especially suitable for long-life road pavement.

Exploring Resistant Sources of Chickpea against Fusarium oxysporum f. sp. ciceris in Dryland Areas

Fusarium wilt is a fungal disease that has a significant impact on chickpeas worldwide. This study examined the response of 58 chickpea genotypes to Fusarium wilt. The experiment was conducted over two growing seasons at the Sararoud and Maragheh research stations at the Drylands Agricultural Research Institute of Iran. Genotype resistance was screened through wilt incidence records and nonparametric stability statistic evaluation. The identified resistant genotypes were then evaluated in the greenhouse for their response to four isolates of Fusarium oxysporum f. sp. ciceris (races 1/BC, 2, 4, and 6). Out of 58 genotypes, 32 exhibited moderate resistance, while 24 showed strong resistance abilities. Under warmer conditions, disease severity was higher, with scores at the Sararoud location being higher than those at the Maragheh location. Of the total genotypes across all locations and years, 41.4% were resistant, 55.17% were moderately resistant, 1.72% were susceptible, and 1.72% were highly susceptible. The nonparametric stability measures S(1), S(2), and S(3) identified FLIP 05-42C and FLIP 05-43C as stable and resistant genotypes. The study found that Azad/Hashem K3 was stable based on the non-parametric stability measure S(6). Other resistant genotypes were identified using stability parameters NP(1), NP(3), and NP(4), while FLIP 05-104C was identified by NP(2). The genotypes selected by nonparametric stability parameters showed resistance against at least two Fusarium oxysporum f. sp. ciceris races. The screening method and nonparametric stability statistics used in this study were effective in identifying sources of resistance to Fusarium oxysporum f. sp. ciceris.

Investigation on nanoindentation and TOF-SIMS applications in the hydrogen and oxygen absorption behavior of Zr-Sn-Nb alloys

This paper focuses on nanoindentation and TOF-SIMS (time-of-flight secondary ion mass spectrometry) small-scale test methods in the study of hydrogen absorption and oxygenation behavior analysis of Zr-Sn-Nb oxidized at 650°C −1200 °C. The CSM (Continuous Stiffness Method) test demonstrates the hardness fluctuations caused by element proliferation in post-high temperature oxidation microstructures. The deformation resistance ability of typical microstructures is as follows: β-Zr layer > α-Zr(O) layer > ZrO2 layer. In addition, hydrogen-induced softening occurred in steam-containing hydrogen conditions (HIT=2～3Gpa), compared to steam (HIT=5～16Gpa). The 1200℃ load-displacement curve demonstrates that the pop-in (or pop-out) effect exists in the Zr-Sn-Nb alloy, related to the influence of hydrogen charge, essentially to dislocation nucleation, winding, and movement. TOF-SIMS provides an effective method for small molecular chemical elements, such as H and O, while ZrO, ZrO2, ZrO2H, ZrO3H, OH, and O2 ions also be found. Based on these results, this study also hypothesizes the OH- dominated oxidation reaction equation.

High-efficient electrooxidation of ethylene glycol and ethanol on PdSn alloy loaded by versatile poly(3,4-ethylenedioxythiophene)

Developing a novel catalyst with lower noble-metal loading and higher catalytic efficiency is significant for promoting the widespread application of direct alcohol fuel cells (DAFCs). In this work, poly(3,4-ethylenedioxythiophene) (PEDOT) supported the PdSn alloy (PdSn/PEDOT) were simply synthesized and their electrocatalytic performance toward the oxidation of ethylene glycol and ethanol (EGOR and EOR) were investigated in alkaline media, respectively. In comparison with other control catalysts, the optimized Pd4Sn6/PEDOT catalyst exhibits the highest mass activity (7125/4166 mA mgPd−1) and specific activity (26/15 mA cm−2) towards EGOR/EOR. The mass activity of Pd4Sn6/PEDOT for EGOR and EOR are 11.9 and 10.9 times higher than commercial Pd/C, respectively. Moreover, chronoamperometry (CA) and successive cyclic voltammetry (CV) tests show that the CO resistance ability and durability of the Pd4Sn6/PEDOT catalyst were superior to Pd4Sn6, Pd/PEDOT and commercial Pd/C catalysts, which can be attributed to the d-band center of Pd can be effectively downshifted and the interface strain effect between electrons caused by the conjugated structure between PEDOT groups. This work provides an effective strategy for the development of highly efficient anode catalysts of DAFCs.

Ca2+, Fe3+ co-crosslinked tannic acid-bridged sodium alginate gel membrane for organic solvent nanofiltration

It is necessary to prepare a nanofiltration membrane with high permeation flux that can be used in the field of organic solvents. Gel membranes have a high solvent permeation flux, but their chained macromolecular structure is often unstable. In this study, tannic acid-bridged sodium alginate (TAx-Ca/FeSA) organic solvent nanofiltration (OSN) membranes were prepared by the phase transition method using aqueous Ca2+ and Fe3+ solutions as cross-linking agents. TA can interact with SA through hydrogen bonding hydrophobic bonding and other interactions to form an interpenetrating three-dimensional network structure. Compared with Ca/FeSA membrane, the average pore size of TA0.125-Ca/FeSA membrane was reduced from 1.03 nm to 0.74 nm, and the porosity was increased from 47.62 to 59.2 %. In addition, the TA0.125-Ca/FeSA membrane has the characteristics of a negative charge, super hydrophilicity, and high mechanical properties, exhibits a high permeation flux of 48.97 L·m−2·h−1·bar−1 with a rejection of 96.25 % for Congo red ethanol solution, has excellent solvent resistance, stain resistance, and self-cleaning ability. The TA0.125-Ca/FeSA membrane was demonstrated to have great potential for application in the fields of purification and solvent recovery.

A self-floating integrated hydrogel evaporator with efficient salt resistance and thermal localization for efficient solar water desalination

Solar-driven interfacial evaporation technology was considered a promising way to effectively alleviate the global freshwater crisis. However, it is still a major challenge to design evaporators with efficient thermal management, salt resistant and self-floating ability to realize efficient clean water production. Here, we design a double-layer hydrogel evaporator with self-floating system. The evaporator is prepared from expanded polystyrene board, poly (vinyl alcohol), polyvinylpyrrolidone, agar and conductive carbon black. The structural design of the evaporator improves water transport capacity of the evaporation system and effectively reduces heat loss, so that the evaporator has efficient salt resistance and thermal localization. The evaporator demonstrates an outstanding evaporation rate and evaporation efficiency of 2.77 kg m-2h−1 and 94.25 % under 1 kW m−2 illumination. Additionally, the evaporator exhibits good stability in the 10-cycle solar evaporation experiment. Furthermore, the evaporator exhibits excellent salt resistance in 3.5 wt% NaCl solution during continuous evaporation for 9 h at 1 kW m−2 illumination. Moreover, the purification rates of the organic wastewater 4-nitrophenol and methylene blue by the evaporator reached 99.8 % and 100 %, respectively. This evaporator has stable and efficient capability of solar water purification, providing a new way for large-scale solar desalination and water purification.

Dry wear and corrosive wear behavior of laser-cladded Co19.6Cr19.6Fe19.6Ni19.6(B13.72Si5.88)19.6Y2 and Fe43.6Ni17.4Cr9Co6B17.5Si1.5Nb5 coatings

Corrosive wear is a key factor affecting the safe operation of offshore engineering equipment. In this study, Co19.6Cr19.6Fe19.6Ni19.6(B13.72Si5.88)19.6Y2 and Fe43.6Ni17.4Cr9Co6B17.5Si1.5Nb5 coatings were prepared on the surface of 304 stainless steel using laser cladding technology. Dry wear and corrosive wear behavior of both coatings and 304 stainless steel were comparatively studied under different loads. The results show that both coatings are mainly composed of FCC solid solution, boride, and Laves phases. The average microhardness of Co19.6Cr19.6Fe19.6Ni19.6(B13.72Si5.88)19.6Y2 and Fe43.6Ni17.4Cr9Co6B17.5Si1.5Nb5 coatings are 578.6 HV0.2 and 632.5 HV0.2, respectively. The dry wear resistance of Fe43.6Ni17.4Cr9Co6B17.5Si1.5Nb5 coating is approximately 3 times that of 304 stainless steel under all friction load conditions. It can be found that the Fe43.6Ni17.4Cr9Co6B17.5Si1.5Nb5 coating with high hardness is less sensitive to friction load changes during dry wear process. In 3.5 wt% NaCl solution, the corrosive wear resistance of CoCrFeNiBSiY coating under friction loads of 30 N and 50 N is 2.68 times and 2.83 times that of 304 stainless steel, respectively. The excellent corrosive wear resistance performance of the CoCrFeNiBSiY coating is mainly attributed to its superior corrosion resistance and repassivation ability. During the corrosive wear process, a dense passivation film is formed on the surface of both coatings, which significantly reduces their friction coefficient and volume loss rate.

Enterprise digital transformation and supply chain resilience

Digitalization provides new opportunities for enhancing supply chain resilience and security levels. This paper, using Chinese listed companies as research samples, characterizes enterprise supply chain resilience in terms of supply chain resistance and recovery ability. By constructing an empirical econometric model, it examines the impact of enterprise digitalization level on supply chain resilience. The results show that the level of digitalization significantly enhances supply chain resilience. Furthermore, heterogeneity tests indicate that the improvement effect of enterprise digitalization on supply chain resilience is more significant in state-owned enterprises and companies with higher levels of marketization.

Improvement of butt-fusion welding procedure and performance evaluation method for thick-walled bimodal polyethylene pipes

High-density polyethylene (HDPE) pipes have been continuously improved by the progress made by the resin industry and pipe manufacturers. Together with the advanced technology of welding equipment in terms of structure reliability and automations, HDPE pipes have been gradually applied to higher pressure level, bigger diameter, and thicker walls in operations which have become the preferred piping system for nuclear safety application in transporting cooling seawater. There are substantial differences in parameter settings when applying heat and force during different welding procedures, as well as the complicated evaluation methods for mechanical properties, which causes communication barriers between engineers and researchers. Thus, it is necessary to comprehensively study the welding procedures and evaluation methods to standardize the evaluation protocols in the industry. In this paper, based on the assumptions of temperature effect and molecular chain diffusion dynamics at the welding interface, the optimization of the welding procedure is proposed. Some well-established evaluation methods have been used for performance assessment and their feasibilities are discussed. The idea of creating crack along the weld interface is adopted as new method to evaluate the material ability of fracture resistance. Specimens with unilateral notch and weld interface crack are proposed and subjected for quasi-static axial tensile test. The fracture stress and fracture energy at the welding interface are used to differentiate the quality of the joint from different welding procedures. The fracture morphologies of the weld interface are analyzed. A complete picture is drawn for the mechanical fracture resistance of the weld interface. The method used in this paper can be corelated to the pipeline design conditions, therefore could be applied to the real-time engineering applications. Moreover, the evaluation method proposed in this paper is simple, reliable, and easy to implement.

Tribological investigation of ceramic incorporated novel compositionally graded multilayer tungsten alloys

In this study, novel compositionally graded tungsten alloys incorporating ceramics were prepared using mechanical alloying and pressure-assisted vacuum hot press (VHP) sintering. Three distinct tungsten compositions (W1, W2, and W3) were developed with varying alloying elements and reinforcements, were stacked layer-wise, and then sintered using VHP. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques were employed to analyze the morphology and microstructural features of synthesized alloys. The effect of alloying elements and reinforcements on mechanical properties and wear behavior was examined. The results showed improvement in mechanical characteristics and enhanced wear resistance of the compositionally graded tungsten alloys. The hardness was increased due to the formation of carbide phases during milling and sintering. The W1 side exhibited a hardness of 8.4 GPa, while the W3 side reached a hardness of 13.3 GPa. Additionally, the wear behavior of both sides (W1 and W3) was also investigated under different applied loads. At a load of 10 N, the W1 surface exhibited a minimum specific wear rate of 3 × 10−6 mm3/Nm, attributed to the presence of MWCNTs and WC phase. However, the W3 surface reinforced with TiC and cBN showed a minimum specific wear rate of 9 × 10−7 mm3/Nm at a higher load of 20 N. This indicates that the W3 side possessed superior hardness and wear resistance ability as compared to the W1 side of compositionally graded tungsten alloys. The novel compositionally graded approach is useful for developing tungsten alloys with tailored mechanical properties for wear resistance applications.

Soft skills unveiled: a comprehensive exploration of employer preferences and employability essentials

Soft skills have become a critical factor in enhancing individual employability. A deeper understanding of the specific soft skills valued by employers in various types of enterprises enables higher education institutions to more precisely cultivate these qualities in students. This study focuses on 15 essential soft skill indicators categorized into three key facets: personal, social, and methodological skills. Through the analysis of 366,077 job advertisements, we establish keyword libraries for different indicators, facilitating the identification of the types of soft skills emphasized in each advertisement. Our findings reveal that small and medium-sized enterprises (SMEs) prioritize a range of soft skills, except for creativity/innovation skills, analytical skills, and continuous improvement skills. On the other hand, state-owned enterprises (SOEs) exhibit a demand for as many as 14 out of 15 soft skill indicators, surpassing private enterprises, except for creativity/innovation skills. However, this emphasis on different soft skills does not necessarily result in salary differentials. Soft skill requirements linked to personal traits, such as professional ethics, commitment to work, stress resistance, and self-learning abilities, do not correlate with higher salaries. Conversely, soft skills related to socialization, like teamwork, leadership, and social networking, are associated with higher salaries. The results of this study reveal employers’ demand for various soft skills. Nevertheless, it is worth noting that this demand is not adequately reflected in salary levels. Employers should carefully consider and strive for a more equitable representation of soft skills in the determination of salaries.

Alloying strategy to stabilize monocrystalline zinc anode under high utilization and working capacity

Zn(002) has been proven as a dendrite-free anode for Zn batteries. However, stable Zn plating/stripping behavior at an areal capacity exceeding 5 mAh cm−2 has remained unfulfilled so far. In this study, we show that the planar deposit on pure Zn (002) substrate is loosely stacked with high corrosion tendency by the aqueous electrolyte, the key obstacle to achieving considerable efficiency under high-capacity working conditions. To mitigate the side reactions, we introduce an alloying approach by combining monocrystalline Zn(002) with eutectic Al and Cu. The alloying strategy enhances the electrostatic interaction between deposits and substrate, favoring a dense-packed deposition morphology with improved corrosion resistant ability. Solid solution property of Al and Cu in Zn matrix also ensures the structure stability during repeated plating/stripping cycles. As a result, significant extension in cycle life of Zn alloy (002)-based symmetric cells even under 50 mA cm−2 and 25 mAh cm−2 and performance with high utilization also achieves a leading level without extra methods on surface protection. The modified Zn alloy (002) anode induces high anode utilization, paving the way for Zn batteries to meet the requirements of practical applications.

Variations in Cold Resistance and Contents of Bioactive Compounds among Dendrobium officinale Kimura et Migo Strains.

Dendrobium officinale is a valuable traditional Chinese herbal plant that is both medicinal and edible. However, the yield of wild Dendrobium officinale is limited. Adverse stress affects the growth, development, and yield of plants, among which low temperature is the primary limiting factor for introducing Dendrobium officinale to high-latitude areas and expanding the planting area. Therefore, this study aims to explore the variations in growth ability, cold resistance, and contents of bioactive compounds among different Dendrobium officinale strains. Four strains of Dendrobium officinale were selected as experimental materials and were subjected to low-temperature stress (4 °C). The agronomic traits, physiological indices, as well as the expressions of cold resistance-related genes (HSP70, DcPP2C5, DoCDPK1, and DoCDPK6) in the roots and leaves of Dendrobium officinale, were determined. The contents of bioactive compounds, including polysaccharides, flavonoids, and phenols were also measured. Compared with the other strains, Xianju had the highest seed germination and transplantation-related survival rates. Under low-temperature stress, Xianju exhibited the strongest cold resistance ability, as revealed by the changes in water contents, chlorophyll levels, electrical conductivities, enzyme activities, and expressions of the cold resistance-related genes. Additionally, the polysaccharide content of Xianju increased the most, while the stem flavonoid and leaf phenol contents were elevated in all four strains under cold treatment. Therefore, selecting excellent performing strains is expected to expand the planting area, improve the yield, and increase the economic benefits of Dendrobium officinale in high latitude areas with lower temperatures.

Effects of internal migrants' health on economic resilience in China's Yangtze River Delta urban agglomeration: moderating effects of basic public health services.

Internal migrants constitute a significant generality in the socioeconomic development of developing countries. With the frequent occurrence of major public health emergencies, obstacles to labor supply due to health issues among internal migrants not only affect their livelihood stability but also urban economic resilience. Moreover, the design of basic public health service systems tends to favor local residents over internal migrants, further exacerbating the health and employment risks of internal migrants. As a result, urban economic resilience faces significant challenges. The objective of this study was to deconstruct economic resilience into economic resistance and recovery abilities, investigate the net effect and its heterogeneity of internal migrants' health on economic resilience in China's Yangtze River Delta urban agglomeration (CYRD), and the mediating effect from labor participation rate and labor time supply, as well as the moderating effect of basic public health services. Based on the China Migrants Dynamic Survey data (CMDS), the study empirically estimated the effects of internal migrants' health on economic resilience in CYRD through microeconometric analysis methods, mediating and moderating effect model. Our findings indicate that internal migrants' health has a positive effect on economic resilience in CYRD. For each unit increase in migrants' health, it will drive up the average economic resistance ability by 0.0186 and the average recovery ability by 0.0039. Secondly, the net effects of migrants' health on economic resilience show significant structural differences, industry and city heterogeneity. The effect of migrants' health on economic resistance ability is significantly higher than that on economic recovery ability; The effect of migrants' health on economic resilience of the secondary industry is higher than that of the tertiary industry; The cities with high economic resistance and recovery abilities have more prominent positive effect from migrants' health. Thirdly, migrants' health not only has a direct effect on the economic resistance and recovery abilities, but also has a mediating effect on which through labor participation rate and labor time supply. Enhancing the accessibility and quality of basic public health services is beneficial for enhancing the positive effects of internal migrants' health on economic resilience.