Microwave-assisted exploration of the electron configuration-dependent electrocatalytic urea oxidation activity of 2D porous NiCo_(2)O_(4) spinel

Urea holds promise as an alternative water-oxidation substrate in electrolytic cells.High-valence nickelbased spinel,especially after heteroatom doping,excels in urea oxidation reactions(UOR).However,traditional spinel synthesis methods with prolonged high-temperature reactions lack kinetic precision,hindering the balance between controlled doping and highly active two-dimensional(2D)porous structures design.This significantly impedes the identification of electron configuration-dependent active sites in doped 2D nickel-based spinels.Herein,we present a microwave shock method for the preparation of 2D porous NiCo_(2)O_(4)spinel.Utilizing the transient on-off property of microwave pulses for precise heteroatom doping and 2D porous structural design,non-metal doping(boron,phosphorus,and sulfur)with distinct extranuclear electron disparities serves as straightforward examples for investigation.Precise tuning of lattice parameter reveals the impact of covalent bond strength on NiCo_(2)O_(4)structural stability.The introduced defect levels induce unpaired d-electrons in transition metals,enhancing the adsorption of electron-donating amino groups in urea molecules.Simultaneously,Bode plots confirm the impact mechanism of rapid electron migration caused by reduced band gaps on UOR activity.The prepared phosphorus-doped 2D porous NiCo_(2)O_(4),with optimal electron configuration control,outperforms most reported spinels.This controlled modification strategy advances understanding theoretical structure-activity mechanisms of high-performance 2D spinels in UOR.

Microwave shock motivating the Sr substitution of 2D porous GdFeO_(3) perovskite for highly active oxygen evolution

The incorporation of partial A-site substitution in perovskite oxides represents a promising strategy for precisely controlling the electronic configuration and enhancing its intrinsic catalytic activity.Conventional methods for A-site substitution typically involve prolonged high-temperature processes.While these processes promote the development of unique nanostructures with highly exposed active sites,they often result in the uncontrolled configuration of introduced elements.Herein,we present a novel approach for synthesizing two-dimensional(2D)porous GdFeO_(3) perovskite with A-site strontium(Sr)substitution utilizing microwave shock method.This technique enables precise control of the Sr content and simultaneous construction of 2D porous structures in one step,capitalizing on the advantages of rapid heating and cooling(temperature~1100 K,rate~70 K s^(-1)).The active sites of this oxygen-rich defect structure can be clearly revealed through the simulation of the electronic configuration and the comprehensive analysis of the crystal structure.For electrocatalytic oxygen evolution reaction application,the synthesized 2D porous Gd_(0.8)Sr_(0.2)FeO_(3) electrocatalyst exhibits an exceptional overpotential of 294 mV at a current density of 10 mA cm^(-2)and a small Tafel slope of 55.85 mV dec^(-1)in alkaline electrolytes.This study offers a fresh perspective on designing crystal configurations and the construction of nanostructures in perovskite.

Understanding the oxidation chemistry of Ti_(3)C_(2)T_(x)(MXene)sheets and their catalytic performances

Transition metal carbides and nitrides(MXenes)nanosheets are attractive two-dimensional(2D)materials,but they suffer from oxidation/degradation issues during storage and/or applications due to their sensitivity to water and oxygen.Despite the great research progress,the exact oxidation kinetics of Ti_(3)C_(2)T_(x)(MXene)and their final products after oxidation are not fully understood.Herein,we systematically tracked the oxidation process of few-layer Ti_(3)C_(2)T_(x) nanosheets in an aqueous solution at room temperature over several weeks.We also studied the oxidation effects on the electrocatalytic properties of Ti_(3)C_(2)T_(x) for hydrogen evolution reaction and found that the overpotential to achieve a current density of 10 mA cm^(-2)increases from 0.435 to 0.877 V after three weeks of degradation,followed by improvement to stabilized values of around 0.40 V after eight weeks.These results suggest that severely oxidized MXene could be a promising candidate for designing efficient catalysts.According to our detailed experimental characterization and theoretical calculations,unlike previous studies,black titanium oxide is formed as the final product in addition to white Ti(IV)oxide and disordered carbons after the complete oxidation of Ti_(3)C_(2)T_(x).This work presents significant advancements in better understanding of 2D Ti_(3)C_(2)T_(x)(MXene)oxidation and enhances the prospects of this material for various applications.

Computationally guided design and synthesis of dual-drug loaded polymeric nanoparticles for combination therapy

Single-drug therapies or monotherapies are often inadequate,particularly in the case of life-threatening diseases like cancer.Consequently,combination therapies emerge as an attractive strategy.Cancer nanomedicines have many benefits in addressing the challenges faced by small molecule therapeutic drugs,such as low water solubility and bioavailability,high toxicity,etc.However,it remains a significant challenge in encapsulating two drugs in a nanoparticle.To address this issue,computational methodologies are employed to guide the rational design and synthesis of dual-drug-loaded polymer nanoparticles while achieving precise control over drug loading.Based on the sequential nanoprecipitation technology,five factors are identified that affect the formulation of drug candidates into dual-drug loaded nanoparticles,and then screened 176 formulations under different experimental conditions.Based on these experimental data,machine learning methods are applied to pin down the key factors.The implementation of this methodology holds the potential to signif-icantly mitigate the complexities associated with the synthesis of dual-drug loaded nanoparticles,and the co-assembly of these compounds into nanoparticulate systems demonstrates a promising avenue for combination therapy.This approach provides a new strategy for enabling the streamlined,high-throughput screening and synthesis of new nanoscale drug-loaded entities.

Management of gestational diabetes mellitus via nutritional interventions:The relevance of gastric emptying

Gestational diabetes mellitus(GDM)represents one of the most common medical complications of pregnancy and is important to the well-being of both mothers and offspring in the short and long term.Lifestyle intervention remains the mainstay for the management of GDM.The efficacy of nutritional approaches(e.g.calorie restriction and small frequent meals)to improving the maternal-neonatal outcomes of GDM was attested to by Chinese population data,discussed in two articles in recent issues of this journal.However,a specific focus on the relevance of postprandial glycaemic control was lacking.Postprandial rather than fasting hyperglycaemia often represents the predominant manifestation of disordered glucose homeostasis in Chinese women with GDM.There is now increasing appreciation that the rate of gastric emptying,which controls the delivery of nutrients for digestion and absorption in the small intestine,is a key determinant of postprandial glycaemia in both health,type 1 and 2 diabetes.It remains to be established whether gastric emptying is abnormally rapid in GDM,particularly among Chinese women,thus contributing to a predisposition to postprandial hyperglycaemia,and if so,how this influences the therapeutic response to nutritional interventions.It is essential that we understand the role of gastric emptying in the regulation of postprandial glycaemia during pregnancy and the potential for its modulation by nutritional strategies in order to improve postprandial glycaemic control in GDM.

Rationalizing the impact of oxygen vacancy on polysulfide conversion kinetics for highly efficient lithium-sulfur batteries

The“shuttle effect”of lithium polysulfides(LiPSs)is a huge challenge for practical use of high-energydensity lithium-sulfur(Li-S)batteries,and one of the main reasons is the sluggish kinetics of sulfur conversion.Metal oxides are able to expedite the sulfur electrochemistry,and the structural defects enhance the adsorption-conversion ability of metal oxides for polysulfides.However,a significant research gap still remains regarding the relationship between the oxygen vacancy concentration and the adsorptivecatalytic performance of metal oxides.Herein,we establish a correlation between oxygen vacancy concentration and adsorptive-catalytic properties by using tungsten oxide(WO_(x))as model catalysts.It is revealed that high-concentration oxygen vacancy is beneficial for enhancing the binding between tungsten oxide and LiPSs,reducing the energy barrier of Li_(2)S decomposition,and promoting polysulfide conversion kinetics.Consequently,the Li-S batteries using the tungsten oxide with high-concentration oxygen vacancies deliver high initial discharge capacity of 1169 mA h g^(-1)at 0.2 C and 865 mA h g^(-1)at 2 C,low attenuation rate of 0.064%per cycle over 1100 cycles at 2 C.With a high sulfur area loading of 5.34 mg cm^(-2),the Li-S batteries still exhibit high initial gravimetric capacity of 982 mA h g^(-1)at 0.1 C and areal capacity of 5.92 mA h cm^(-2).This work promotes the feasibility of defect engineering on metal oxides as an effective mean to enhance the practicality of Li-S batteries.

Effect of drying-wetting cycles on pore characteristics and mechanical properties of enzyme-induced carbonate precipitation-reinforced sea sand

Enzyme-induced carbonate precipitation(EICP)is an emanating,eco-friendly and potentially sound technique that has presented promise in various geotechnical applications.However,the durability and microscopic characteristics of EICP-treated specimens against the impact of drying-wetting(D-W)cycles is under-explored yet.This study investigates the evolution of mechanical behavior and pore charac-teristics of EICP-treated sea sand subjected to D-W cycles.The uniaxial compressive strength(UCS)tests,synchrotron radiation micro-computed tomography(micro-CT),and three-dimensional(3D)recon-struction of CT images were performed to study the multiscale evolution characteristics of EICP-reinforced sea sand under the effect of D-W cycles.The potential correlations between microstructure characteristics and macro-mechanical property deterioration were investigated using gray relational analysis(GRA).Results showed that the UCS of EICP-treated specimens decreases by 63.7% after 15 D-W cycles.The proportion of mesopores gradually decreases whereas the proportion of macropores in-creases due to the exfoliated calcium carbonate with increasing number of D-W cycles.The micro-structure in EICP-reinforced sea sand was gradually disintegrated,resulting in increasing pore size and development of pore shape from ellipsoidal to columnar and branched.The gray relational degree suggested that the weight loss rate and UCS deterioration were attributed to the development of branched pores with a size of 100-1000 m m under the action of D-W cycles.Overall,the results in this study provide a useful guidancee for the long-term stability and evolution characteristics of EICP-reinforced sea sand under D-W weathering conditions.

Effects of pressure relief holes on coal burst:Insights from true-triaxial unloading tests

Drilling pressure relief is one of the methods to reduce the risk of coal bursts in deep mines.However,the effect of the drill hole orientations has not been studied well enough to understand their impact on the burst failure mechanism.In this study,we investigated two designs of drill hole orientations.The first design includes drill holes located on the upper free face of the rectangular samples and labelled as upper hole(UH)and centre hole(CH)e the long axes of the drill holes are aligned with minor principal stress,s3,direction.The second design includes drill holes at the top(TH)and the side(SH)of the rectangular samples in which the long axes of the drill holes are aligned with the maximum,s1,and intermediate principal stress,s2,directions,respectively.The coal samples with the proposed drill hole orientations were subjected to the true-triaxial unloading coal burst tests.The results show that the drill holes reduce the risk of coal bursts.However,we found that the intensity of coal burst was significantly reduced with the SH-type,followed by the CH-types.We also observed that the coal burst intensity is reduced better for the CH,UH,TH,and SH-type drilling patterns.However,it was found that the orientations of drill holes have little influence on the failure mode(splitting).The acoustic emission(AE)activities for coal with drill holes noticeably decreased,especially for the UH and CH layouts.The drill holes reduced the upper limit of the AE entropy(chaos of microcracks generation).However,regarding reducing the coal burst risk,the TH and SH are less effective than UH and CH.

Layer chicken microbiota:a comprehensive analysis of spatial and temporal dynamics across all major gut sections

Background The gut microbiota influences chicken health,welfare,and productivity.A diverse and balanced microbiota has been associated with improved growth,efficient feed utilisation,a well-developed immune system,disease resistance,and stress tolerance in chickens.Previous studies on chicken gut microbiota have predominantly focused on broiler chickens and have usually been limited to one or two sections of the digestive system,under con-trolled research environments,and often sampled at a single time point.To extend these studies,this investigation examined the microbiota of commercially raised layer chickens across all major gut sections of the digestive system and with regular sampling from rearing to the end of production at 80 weeks.The aim was to build a detailed picture of microbiota development across the entire digestive system of layer chickens and study spatial and temporal dynamics.Results The taxonomic composition of gut microbiota differed significantly between birds in the rearing and pro-duction stages,indicating a shift after laying onset.Similar microbiota compositions were observed between proven-triculus and gizzard,as well as between jejunum and ileum,likely due to their anatomical proximity.Lactobacil-lus dominated the upper gut in pullets and the lower gut in older birds.The oesophagus had a high proportion of Proteobacteria,including opportunistic pathogens such as Gallibacterium.Relative abundance of Gallibacterium increased after peak production in multiple gut sections.Aeriscardovia was enriched in the late-lay phase compared to younger birds in multiple gut sections.Age influenced microbial richness and diversity in different organs.The upper gut showed decreased diversity over time,possibly influenced by dietary changes,while the lower gut,specifi-cally cecum and colon,displayed increased richness as birds matured.However,age-related changes were inconsist-ent across all organs,suggesting the influence of organ-specific factors in microbiota maturation.Conclusion Addressing a gap in previous research,this study explored the microbiota across all major gut sections and tracked their dynamics from rearing to the end of the production cycle in commercially raised layer chickens.This study provides a comprehensive understanding of microbiota structure and development which help to develop targeted strategies to optimise gut health and overall productivity in poultry production.

Tackling the proton limit under industrial electrochemical CO_(2)reduction by a local proton shuttle

Industrial CO_(2)electroreduction has received tremendous attentions for resolution of the current energy and environmental crisis,but its performance is greatly limited by mass transport at high current density.In this work,an ion‐polymer‐modified gas‐diffusion electrode is used to tackle this proton limit.It is found that gas diffusion electrode‐Nafion shows an impressive performance of 75.2%Faradaic efficiency in multicarbon products at an industrial current density of 1.16 A/cm^(2).Significantly,in‐depth electrochemical characterizations combined with in situ Raman have been used to determine the full workflow of protons,and it is found that HCO_(3)^(−)acts as a proton pool near the reaction environment,and HCO_(3)^(−)and H_(3)O^(+)are local proton donors that interact with the proton shuttle−SO_(3)^(−)from Nafion.With rich proton hopping sites that decrease the activation energy,a“Grotthuss”mechanism for proton transport in the above system has been identified rather than the“Vehicle”mechanism with a higher energy barrier.Therefore,this work could be very useful in terms of the achievement of industrial CO_(2)reduction fundamentally and practically.

Digital Twins for Engineering Asset Management:Synthesis,Analytical Framework,and Future Directions

Effective engineering asset management(EAM)is critical to economic development and improving livability in society,but its complexity often impedes optimal asset functionalities.Digital twins(DTs)could revolutionize the EAM paradigm by bidirectionally linking the physical and digital worlds in real time.There is great industrial and academic interest in DTs for EAM.However,previous review studies have predominately focused on technical aspects using limited life-cycle perspectives,failing to holistically synthesize DTs for EAM from the managerial point of view.Based on a systematic literature review,we introduce an analytical framework for describing DTs for EAM,which encompasses three levels:DT 1.0 for technical EAM,DT 2.0 for technical-human EAM,and DT 3.0 for technical-environmental EAM.Using this framework,we identify what is known,what is unknown,and future directions at each level.DT 1.0 addresses issues of asset quality,progress,and cost management,generating technical value.It lacks multi-objective self-adaptive EAM,however,and suffers from high application cost.It is imperative to enable closed-loop EAM in order to provide various functional services with affordable DT 1.0.DT 2.0 accommodates issues of human-machine symbiosis,safety,and flexibility management,generating managerial value beyond the technical performance improvement of engineering assets.However,DT 2.0 currently lacks the automation and security of human-machine interactions and the managerial value related to humans is not prominent enough.Future research needs to align technical and managerial value with highly automated and secure DT 2.0.DT 3.0 covers issues of participatory governance,organization management,sustainable development,and resilience enhancement,generating macro social value.Yet it suffers from organizational fragmentation and can only address limited social governance issues.Numerous research opportunities exist to coordinate different stakeholders.Similarly,future research opportunities exist to develop DT 3.0 in a more open and complex system.

Biopolymer stabilization of clayey soil

This study investigates the efficacy of sodium alginate(SA),xanthan gum(XG),guar gum(GG)and chitosan(CS)d each applied at five different solid biopolymer-to-water mass ratios(or dosages)and cured for 7 d and 28 d d on the unconfined compressive strength(UCS)performance of a high plasticity clayey soil.Moreover,on identifying the optimum biopolymer-treatment scenarios,their performance was compared against conventional stabilization using hydrated lime.For a given curing time,the UCS for all biopolymers followed a riseefall trend with increasing biopolymer dosage,peaking at an optimum dosage and then subsequently decreasing,such that all biopolymer-stabilized samples mobilized higher UCS values compared to the unamended soil.The optimum dosage was found to be 1.5%for SA,XG and CS,while a notably lower dosage of 0.5%was deemed optimum for GG.Similarly,for a given biopolymer type and dosage,increasing the curing time from 7 d to 28 d further enhanced the UCS,with the achieved improvements being generally more pronounced for XG-and CS-treated cases.None of the investigated biopolymers was able to produce UCS improvements equivalent to those obtained by the 28-d soilelime samples;however,the optimum XG,GG and CS dosages,particularly after 28 d of curing,were easily able to replicate 7-d lime stabilization outcomes achieved with as high as twice the soil’s lime demand.Finally,the fundamental principles of clay chemistry,in conjunction with the soil mechanics framework,were employed to identify and discuss the clayebiopolymer stabilization mechanisms.

Kinetics and mechanisms of non-radically and radically induced degradation of bisphenol A in a peroxymonosulfate-chloride system

Bisphenol A,a hazardous endocrine disruptor,poses significant environmental and human health threats,demanding efficient removal approaches.Traditional biological methods struggle to treat BPA wastewater with high chloride(Cl^(-))levels due to the toxicity of high Cl^(-)to microorganisms.While persulfate-based advanced oxidation processes(PS-AOPs)have shown promise in removing BPA from high Cl^(-)wastewater,their widespread application is always limited by the high energy and chemical usage costs.Here we show that peroxymonosulfate(PMS)degrades BPA in situ under high Cl^(-)concentrations.BPA was completely removed in 30 min with 0.3 mM PMS and 60 mM Cl^(-).Non-radical reactive species,notably free chlorine species,including dissolved Cl2(l),HClO,and ClO−dominate the removal of BPA at temperatures ranging from 15 to 60°C.Besides,free radicals,including•OH and Cl_(2)^(•−),contribute minimally to BPA removal at 60°C.Based on the elementary kinetic models,the production rate constant of Cl2(l)(32.5 M^(−1) s^(−1))is much higher than HClO(6.5×10^(−4) M^(−1) s^(−1)),and its degradation rate with BPA(2×10^(7) M^(−1) s^(−1))is also much faster than HClO(18 M^(−1) s^(−1)).Furthermore,the degradation of BPA by Cl2(l)and HClO were enlarged by 10-and 18-fold at 60°C compared to room temperature,suggesting waste heat utilization can enhance treatment performance.Overall,this research provides valuable insights into the effectiveness of direct PMS introduction for removing organic micropollutants from high Cl^(-)wastewater.It further underscores the critical kinetics and mechanisms within the PMS/Cl⁻system,presenting a cost-effective and environmentally sustainable alternative for wastewater treatment.

Failure behavior and strength model of blocky rock mass with and without rockbolts

To better understand the failure behaviours and strength of bolt-reinforced blocky rocks,large scale extensive laboratory experiments are carried out on blocky rock-like specimens with and without rockbolt reinforcement.The results show that both shear failure and tensile failure along joint surfaces are observed but the shear failure is a main controlling factor for the peak strength of the rock mass with and without rockbolts.The rockbolts are necked and shear deformation simultaneously happens in bolt reinforced rock specimens.As the joint dip angle increases,the joint shear failure becomes more dominant.The number of rockbolts has a significant impact on the peak strain and uniaxial compressive strength(UCS),but little influence on the deformation modulus of the rock mass.Using the Winkler beam model to represent the rockbolt behaviours,an analytical model for the prediction of the strength of boltreinforced blocky rocks is proposed.Good agreement between the UCS values predicted by proposed model and obtained from experiments suggest an encouraging performance of the proposed model.In addition,the performance of the proposed model is further assessed using published results in the literature,indicating the proposed model can be used effectively in the prediction of UCS of bolt-reinforced blocky rocks.

Tackling application limitations of high-safetyγ-butyrolactone electrolytes:Exploring mechanisms and proposing solutions

Developing wide-temperature and high-safety lithium-ion batteries(LIBs)presents significant challenges attributed to the absence of suitable solvents possessing broad liquid range and non-flammability properties.γ-Butyrolactone(GBL)has emerged as a promising solvent;however,its incompatibility with graphite anode has hindered its application.This limitation necessitates a comprehensive investigation into the underlying mechanisms and potential solutions.In this study,we achieve a molecular-level understanding of the perplexing interphase formation process by employing in-situ spectroelectrochemical techniques and density function calculations.Our findings reveal that,even at high salt concentrations,GBL consistently occupies the primary Li^(+)solvation sheath,leading to extensive GBL decomposition and the formation of a high-impedance and inorganic-poor solid-electrolyte interphase(SEI)layer.Contrary to manipulating solvation structures,our research demonstrates that the utilization of filmforming additives with higher reduction potential facilitates the pre-establishment of a robust SEI film on the graphite anode.This approach effectively inhibits GBL decomposition and significantly enhances the battery's lifespan.This study provides the first reported intrinsic understanding of the unique GBLgraphite incompatibility and offers valuable insights for the development of wide-temperature and high-safety LIBs.

Performance of a Combined Energy System Consisting of Solar Collector, Biogas Dry Reforming and Solid Oxide Fuel Cell: An Indian Case Study

An energy production system consisting of a solar collector, biogas dry reforming reactor and solid oxide fuel cell (SOFC) was assumed to be installed in Kolkata, India. This study aims to understand the impact of climate conditions on the performance of solar collectors with different lengths of parabolic trough solar collector (dx) and mass flow rate of heat transfer fluid (m). In addition, this study has evaluated the amount of H2 produced by biogas dry reforming (GH2), the amount of power generated by SOFC (PSOFC) and the maximum number of possible households (N) whose electricity demand could be met by the energy system proposed, considering the performance of solar collector with the different dx and m. As a result, the optimum dx was found to be 4 m. This study revealed that the temperature of heat transfer fluid (Tfb) decreased with the increase in m. Tfb in March, April and May was higher than that in other months, while Tfb from June to December was the lowest. GH2, PSOFC and N in March, April and May were higher than those in other months, irrespective of m. The optimum m was 0.030 kg/s.

Effects of water content, water type and temperature on the rheological behaviour of slag-cement and fly ash-cement paste backfill

The pumping ability and placement performance of fresh cemented paste backfill(CPB) in underground mined cavities depend on its rheological properties. Hence, it is crucial to understand the rheology of fresh CPB slurry, which is related to CPB mixture design and the temperature underground. This paper presented an experimental study investigating the effects of binder type, content, water chemical properties and content, and temperature, on the rheological properties of CPB material prepared using the tailings of a copper mine in South Australia. Portland cement(PC), a newly released commercially manufactured cement called Minecem(MC) and fly ash(FA) were used as the binders added to the mine tailing materials. Various amounts of two different water types were added to the mixtures in the preparation of backfill material slurry. Six different temperatures ranging from 5 to 60 °C were to investigate the effect of temperature on CPB rheology. Overall, the increasing water content and decreasing temperature lead to lower yield stress. Based on the results obtained from the rheological properties of CPB slurry, it was found that at room temperature(25 °C), with regards to the unconfined compressive strength(UCS) performance, the replacement of 4% PC mixed CPB(28 days UCS 425 k Pa) to 3% MC mixed CPB(28 days UCS 519 k Pa), reduced the slurry yield stress from 210.7 to 178.5 Pa. The results also showed that the chemical composition of water affects the yield stress of CPB slurry and that MC mitigates the negative effect of mine-processed water(MW) and thus lead to improve the rheological properties of the slurry. However, the results suggested that the rheological properties of a mixture using MC is very sensitive to the water volume and temperature change. Therefore, using MC in backfill requires better quality control in slump mixing.

Review of the impact of heat stress on reproductive performance of sheep

Heat stress significantly impairs reproduction of sheep,and under current climatic conditions is a significant risk to the efficiency of the meat and wool production,with the impact increasing as global temperatures rise.Evidence from field studies and studies conducted using environmental chambers demonstrate the effects of hot temperatures(≥32℃)on components of ewe fertility(oestrus,fertilisation,embryo survival and lambing)are most destructive when experienced from 5 d before until 5 d after oestrus.Temperature controlled studies also demonstrate that ram fertility,as measured by rates of fertilisation and embryo survival,is reduced when mating occurs during the period 14 to 50 d post-heating.However,the contribution of the ram to heat induced reductions in flock fertility is difficult to determine accurately.Based primarily on temperature controlled studies,it is clear that sustained exposure to high temperatures(≥32℃)during pregnancy reduces lamb birthweight and will,therefore,decrease lamb survival under field conditions.It is concluded that both ewe and ram reproduction is affected by relatively modest levels of heat stress(≥32℃)and this is a concern given that a significant proportion of the global sheep population experiences heat stress of this magnitude around mating and during pregnancy.Despite this,strategies to limit the impacts of the climate on the homeothermy,behaviour,resource use and reproduction of extensively grazed sheep are limited,and there is an urgency to improve knowledge and to develop husbandry practices to limit these impacts.

Role of polyethylene particles in peri-prosthetic osteolysis:A review

There is convincing evidence that particles produced by the wear of joint prostheses are causal in the periprosthetic loss of bone,or osteolysis,which,if it progresses,leads to the phenomenon of aseptic loosening.It is important to fully understand the biology of this bone loss because it threatens prosthesis survival,and loosened implants can result in peri-prosthetic fracture,which is disastrous for the patient and presents a difficult surgical scenario.The focus of this review is the bioactivity of polyethylene(PE)particles,since there is evidence that these are major players in the development and progression of osteolysis around prostheses which use PE as the bearing surface.The review describes the biological consequences of interaction of PE particles with macrophages,osteoclasts and cells of the osteoblast lineage,including osteocytes.It explores the possible cellular mechanisms of action of PE and seeks to use the findings to date to propose potential nonsurgical treatments for osteolysis.In particular,a nonsurgical approach is likely to be applicable to implants containing newer,highly cross-linked PEs(HXLPEs),for which osteolysis seems to occur with much reduced PE wear compared with conventional PEs.The caveat here is that we know little as yet about the bioactivity of HXLPE particles and addressing this constitutes our next challenge.

Effects of Glomus mosseae on the toxicity of heavy metals to Vicia faba

A glasshouse pot experiment was conducted to investigate effects of the arbuscular mycorrhizal fungus Glomus mosseae on the growth of Vicia faba and toxicity induced by heavy metals （HMs） （Cu, Zn, Pb and Cd） in a field soil contaminated by a mixture of these metals. There was also uninoculation treatment （NM） simultaneously. Mycorrhizal （GM） plants have significantly increased growth and tolerance to toxicity induced by heavy metals compared with NM plants. P uptake was significantly increased in GM plants. Mycorrhizal symbiosis reduced the transportation of HMs fi＇om root to shoot by immobilizing HMs in the mycorrhizal, shown by increasing the ratios of HMs from root to shoot. Oxidative stress, which can induce DNA damage, is an important mechanism of heavy metal toxicity. GM treatment decreased oxidative stress by intricating antioxidative systems such as peroxidases and non-enzymic systems including soluble protein. The DNA damage induced by heavy metals was detected using comet assay, which showed DNA damage in the plants was decreased by the GM treatment.