Multi-objective optimization and evaluation of supercritical CO_(2) Brayton cycle for nuclear power generation

The supercritical CO_(2) Brayton cycle is considered a promising energy conversion system for Generation IV reactors for its simple layout,compact structure,and high cycle efficiency.Mathematical models of four Brayton cycle layouts are developed in this study for different reactors to reduce the cost and increase the thermohydraulic performance of nuclear power generation to promote the commercialization of nuclear energy.Parametric analysis,multi-objective optimizations,and four decision-making methods are applied to obtain each Brayton scheme’s optimal thermohydraulic and economic indexes.Results show that for the same design thermal power scale of reactors,the higher the core’s exit temperature,the better the Brayton cycle’s thermo-economic performance.Among the four-cycle layouts,the recompression cycle(RC)has the best overall performance,followed by the simple recuperation cycle(SR)and the intercooling cycle(IC),and the worst is the reheating cycle(RH).However,RH has the lowest total cost of investment(C_(tot))of$1619.85 million,and IC has the lowest levelized cost of energy(LCOE)of 0.012$/(kWh).The nuclear Brayton cycle system’s overall performance has been improved due to optimization.The performance of the molten salt reactor combined with the intercooling cycle(MSR-IC)scheme has the greatest improvement,with the net output power(W_(net)),thermal efficiencyη_(t),and exergy efficiency(η_(e))improved by 8.58%,8.58%,and 11.21%,respectively.The performance of the lead-cooled fast reactor combined with the simple recuperation cycle scheme was optimized to increase C_(tot) by 27.78%.In comparison,the internal rate of return(IRR)increased by only 7.8%,which is not friendly to investors with limited funds.For the nuclear Brayton cycle,the molten salt reactor combined with the recompression cycle scheme should receive priority,and the gas-cooled fast reactor combined with the reheating cycle scheme should be considered carefully.

Coupling Effect of Cryogenic Freeze-Thaw Cycles and Chloride Ion Erosion Effect in Pre-Cracked Reinforced Concrete

Chloride (Cl−) ion erosion effects can seriously impact the safety and service life of marine liquefied natural gas(LNG) storage tanks and other polar offshore structures. This study investigates the impact of different low-temperaturecycles (20°C, –80°C, and −160°C) and concrete specimen crack widths (0, 0.3, and 0.6 mm) on the Cl−ion diffusion performance through rapid erosion tests conducted on pre-cracked concrete. The results show thatthe minimum temperature and crack width of freeze-thaw cycles enhance the erosive effect of chloride ions. TheCl− ion concentration and growth rate increased with the increasing crack width. Based on the experimental modeland in accordance with Fick’s second law of diffusion, the Cl− ion diffusion equation was modified by introducingcorrection factors in consideration of the freeze-thaw temperature, crack width, and their coupling effect.The experimental and fitting results obtained from this model can provide excellent reference for practical engineeringapplications.

Dynamic simulation analysis of molten salt reactor-coupled air-steam combined cycle power generation system

A nonlinear dynamic simulation model based on coordinated control of speed and flow rate for the molten salt reactor and combined cycle systems is proposed here to ensure the coordination and stability between the molten salt reactor and power system.This model considers the impact of thermal properties of fluid variation on accuracy and has been validated with Simulink.This study reveals the capability of the control system to compensate for anomalous situations and maintain shaft stability in the event of perturbations occurring in high-temperature molten salt tank outlet parameters.Meanwhile,the control system’s impact on the system’s dynamic characteristics under molten salt disturbance is also analyzed.The results reveal that after the disturbance occurs,the controlled system benefits from the action of the control,and the overshoot and disturbance amplitude are positively correlated,while the system power and frequency eventually return to the initial values.This simulation model provides a basis for utilizing molten salt reactors for power generation and maintaining grid stability.

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.

Involvement of the ABA-and H_(2)O_(2)-Mediated Ascorbate-Glutathione Cycle in the Drought Stress Responses of Wheat Roots

Abscisic acid(ABA),hydrogen peroxide(H_(2)O_(2)) and ascorbate(AsA)–glutathione(GSH)cycle are widely known for their participation in various stresses.However,the relationship between ABA and H_(2)O_(2) levels and the AsA–GSH cycle under drought stress in wheat has not been studied.In this study,a hydroponic experiment was conducted in wheat seedlings subjected to 15%polyethylene glycol(PEG)6000–induced dehydration.Drought stress caused the rapid accumulation of endogenous ABA and H_(2)O_(2) and significantly decreased the number of root tips compared with the control.The application of ABA significantly increased the number of root tips,whereas the application of H_(2)O_(2) markedly reduced the number of root tips,compared with that under 15%PEG-6000.In addition,drought stress markedly increased the DHA,GSH and GSSG levels,but decreased the AsA levels,AsA/DHA and GSH/GSSG ratios compared with those in the control.The activities of the four enzymes in the AsA–GSH cycle were also markedly increased under drought stress,including glutathione reductase(GR),ascorbate peroxidase(APX),monodehydroascorbate reductase(MDHAR)and dehydroascorbate reductase(DHAR),compared with those in the control.However,the application of an ABA inhibitor significantly inhibited GR,DHAR and APX activities,whereas the application of an H_(2)O_(2) inhibitor significantly inhibited DHAR and MDHAR activities.Furthermore,the application of ABA inhibitor significantly promoted the increases of H_(2)O_(2) and the application of H_(2)O_(2) inhibitor significantly blocked the increases of ABA,compared with those under 15% PEG-6000.Taken together,the results indicated that ABA and H_(2)O_(2) probably interact under drought stress in wheat;and both of them can mediate drought stress by modulating the enzymes in AsA–GSH cycle,where ABA acts as the main regulator of GR,DHAR,and APX activities,and H_(2)O_(2) acts as the main regulator of DHAR and MDHAR activities.

Dual‑Atom Nanozyme Eye Drops Attenuate Inflammation and Break the Vicious Cycle in Dry Eye Disease

Dry eye disease(DED)is a major ocular pathology worldwide,causing serious ocular discomfort and even visual impairment.The incidence of DED is gradually increasing with the highfrequency use of electronic products.Although inflammation is core cause of the DED vicious cycle,reactive oxygen species(ROS)play a pivotal role in the vicious cycle by regulating inflammation from upstream.Therefore,current therapies merely targeting inflammation show the failure of DED treatment.Here,a novel dual-atom nanozymes(DAN)-based eye drops are developed.The antioxidative DAN is successfully prepared by embedding Fe and Mn bimetallic single-atoms in N-doped carbon material and modifying it with a hydrophilic polymer.The in vitro and in vivo results demonstrate the DAN is endowed with superior biological activity in scavenging excessive ROS,inhibiting NLRP3 inflammasome activation,decreasing proinflammatory cytokines expression,and suppressing cell apoptosis.Consequently,the DAN effectively alleviate ocular inflammation,promote corneal epithelial repair,recover goblet cell density and tear secretion,thus breaking the DED vicious cycle.Our findings open an avenue to make the DAN as an intervention form to DED and ROSmediated inflammatory diseases.

Effects of dry-wet cycles on the mechanical properties of sandstone with unloading-induced damage

Sandstone is the fundamental material in various engineering and construction projects.However,the mechanical integrity of sandstone can be compromised by initial unloading damage resulting from activities such as engineering excavations.Furthermore,this degradation is further exacerbated under periodic dry-wet environmental conditions.This study investigated the effects of dry-wet cycles and unloading on the mechanical properties of jointed fine sandstone using uniaxial and triaxial compression tests.These tests were performed on rock samples subjected to varying unloading degrees and different numbers of dry-wet cycles.The results demonstrate that with an increase in the unloading degree from 0%to 70%,there is a corresponding decrease in peak stress ranging from 10%to 33%.Additionally,the cohesion exhibits a reduction of approximately 20%to 25%,while the internal friction angle experiences a decline of about 3.5%to 6%.These findings emphasize a significant unloading effect.Moreover,the degree of peak stress degradation in unloading jointed fine sandstone diminishes with an increase in confining pressure,suggesting that confining pressure mitigates the deterioration caused by dry-wet cycles.Additionally,as the number of dry-wet cycles increases,there is a notable decline in the mechanical properties of the sandstone,evidencing significant dry-wet degradation.Utilizing the Drucker Prager criterion,this study establishes a strength criterion and fracture criterion,denoted asσ1(m,n)and,to quantify the combined impacts of dry-wet cycles and unloading on jointed fine sandstone,which provides a comprehensive understanding of its mechanical behavior under such conditions.

Durable K-ion batteries with 100% capacity retention up to 40,000 cycles

Currently,the major challenge in terms of research on K-ion batteries is to ensure that they possess satisfactory cycle stability and specific capacity,especially in terms of the intrinsically sluggish kinetics induced by the large radius of K+ions.Here,we explore high-performance K-ion half/full batteries with high rate capability,high specific capacity,and extremely durable cycle stability based on carbon nanosheets with tailored N dopants,which can alleviate the change of volume,increase electronic conductivity,and enhance the K+ion adsorption.The as-assembled K-ion half-batteries show an excellent rate capability of 468 mA h g^(−1) at 100 mA g^(−1),which is superior to those of most carbon materials reported to date.Moreover,the as-assembled half-cells have an outstanding life span,running 40,000 cycles over 8 months with a specific capacity retention of 100%at a high current density of 2000 mA g^(−1),and the target full cells deliver a high reversible specific capacity of 146 mA h g^(−1) after 2000 cycles over 2 months,with a specific capacity retention of 113%at a high current density of 500 mA g^(−1),both of which are state of the art in the field of K-ion batteries.This study might provide some insights into and potential avenues for exploration of advanced K-ion batteries with durable stability for practical applications.

Investigation into the Methodology and Implementation of Life Cycle Engineering under China’s Carbon Reduction Target in the Process Industry

The industrial sector is the primary source of carbon emissions in China.In pursuit of meeting its carbon reduction targets,China aims to promote resource consumption sustainability,reduce energy consumption,and achieve carbon neutrality within its processing industries.An effective strategy to promote energy savings and carbon reduction throughout the life cycle of materials is by applying life cycle engineering technology.This strategy aims to attain an optimal solution for material performance,resource consumption,and environmental impact.In this study,five types of technologies were considered:raw material replacement,process reengineering,fuel replacement,energy recycling and reutilization,and material recycling and reutilization.The meaning,methodology,and development status of life cycle engineering technology abroad and domestically are discussed in detail.A multidimensional analysis of ecological design was conducted from the perspectives of resource and energy consumption,carbon emissions,product performance,and recycling of secondary resources in a manufacturing process.This coupled with an integrated method to analyze carbon emissions in the entire life cycle of a material process industry was applied to the nonferrous industry,as an example.The results provide effective ideas and solutions for achieving low or zero carbon emission production in the Chinese industry as recycled aluminum and primary aluminum based on advanced technologies had reduced resource consumption and emissions as compared to primary aluminum production.

Hydrangea serrata extract exerts tumor inhibitory activity against hepatocellular carcinoma HepG2 cells via inducing p27/CDK2-mediated cell cycle arrest and apoptosis

Objective:To examine the inhibitory effect of Hydrangea serrata extract against hepatocellular carcinoma HepG2 cells and its underlying mechanisms.Methods:The effects of Hydrangea serrata extract on growth inhibition of tumor cells and spheroids were assessed using MTT and 3D culture assays.Quantitative real-time PCR and Western blot analyses were employed to investigate the changes in mRNA and protein expression levels of molecules related to cell cycle and apoptosis.Results:Hydrangea serrata extract effectively inhibited the growth of both tumor cells and spheroids.The extract also significantly upregulated p27 mRNA expression and downregulated CDK2 mRNA expression,leading to cell cycle arrest.Moreover,increased BAX/Bcl-2 ratio as well as caspase-9 and-3 were observed after treatment with Hydrangea serrata extract,indicating the induction of tumor cell apoptosis.Conclusions:Hydrangea serrata extract has the potential to alleviate tumors by effectively modulating cell-cycle-related gene expressions and inducing apoptosis,thereby inhibiting tumor growth.

Antitumor Effect of Apcin on Endometrial Carcinoma via p21-Mediated Cell Cycle Arrest and Apoptosis

Objective Endometrial carcinoma(EC)is a prevalent gynecological malignancy characterized by increasing incidence and mortality rates.This underscores the critical need for novel therapeutic targets.One such potential target is cell division cycle 20(CDC20),which has been implicated in oncogenesis.This study investigated the effect of the CDC20 inhibitor Apcin on EC and elucidated the underlying mechanism involved.Methods The effects of Apcin on EC cell proliferation,apoptosis,and the cell cycle were evaluated using CCK8 assays and flow cytometry.RNA sequencing(RNA-seq)was subsequently conducted to explore the underlying molecular mechanism,and Western blotting and coimmunoprecipitation were subsequently performed to validate the results.Animal studies were performed to evaluate the antitumor effects in vivo.Bioinformatics analysis was also conducted to identify CDC20 as a potential therapeutic target in EC.Results Treatment with Apcin inhibited proliferation and induced apoptosis in EC cells,resulting in cell cycle arrest.Pathways associated with apoptosis and the cell cycle were activated following treatment with Apcin.Notably,Apcin treatment led to the upregulation of the cell cycle regulator p21,which was verified to interact with CDC20 and consequently decrease the expression of downstream cyclins in EC cells.In vivo experiments confirmed that Apcin treatment significantly impeded tumor growth.Higher CDC20 expression was observed in EC tissue than in nonmalignant tissue,and increased CDC20 expression in EC patients was associated with shorter overall survival and progress free interval.Conclusion CDC20 is a novel molecular target in EC,and Apcin could be developed as a candidate antitumor drug for EC treatment.

Improved Diurnal Cycle of Precipitation on Land in a Global Non-Hydrostatic Model Using a Revised NSAS Deep Convective Scheme

In relatively coarse-resolution atmospheric models,cumulus parameterization helps account for the effect of subgridscale convection,which produces supplemental rainfall to the grid-scale precipitation and impacts the diurnal cycle of precipitation.In this study,the diurnal cycle of precipitation was studied using the new simplified Arakawa-Schubert scheme in a global non-hydrostatic atmospheric model,i.e.,the Yin-Yang-grid Unified Model for the Atmosphere.Two new diagnostic closures and a convective trigger function were suggested to emphasize the job of the cloud work function corresponding to the free tropospheric large-scale forcing.Numerical results of the 0.25-degree model in 3-month batched real-case simulations revealed an improvement in the diurnal precipitation variation by using a revised trigger function with an enhanced dynamical constraint on the convective initiation and a suitable threshold of the trigger.By reducing the occurrence of convection during peak solar radiation hours,the revised scheme was shown to be effective in delaying the appearance of early-afternoon rainfall peaks over most land areas and accentuating the nocturnal peaks that were wrongly concealed by the more substantial afternoon peak.In addition,the revised scheme enhanced the simulation capability of the precipitation probability density function,such as increasing the extremely low-and high-intensity precipitation events and decreasing small and moderate rainfall events,which contributed to the reduction of precipitation bias over mid-latitude and tropical land areas.

NCAPD2 serves as a potential prognostic biomarker for lung adenocarcinoma and promotes cell proliferation,migration,invasion and cell cycle in vitro

Objectives:The pro-oncogenic effects of NCAPD2 have been extensively studied across various tumor types;however,its precise role within the context of lung adenocarcinoma(LUAD)remains elusive.This study aims to elucidate the biological functions of NCAPD2 in LUAD and unravel the underlying mechanistic pathways.Methods:Utilizing bioinformatics methodologies,we explored the differential expression of NCAPD2 between normal and tumor samples,along with its correlations with clinical-pathological characteristics,survival prognosis,and immune infiltration.Results:In the TCGA-LUAD dataset,tumor samples demonstrated significantly elevated levels of NCAPD2 expression compared to normal samples(p<0.001).Clinically,higher NCAPD2 expression was notably associated with advanced T,N,and M stages,pathologic stage,gender,smoking status,and diminished overall survival(OS).Moreover,differentially expressed genes(DEGs)associated with NCAPD2 were predominantly enriched in pathways related to cell division.Immune infiltration analysis revealed that NCAPD2 expression levels were linked to the infiltration of memory B cells,naïve CD4+T cells,activated memory CD4+T cells,and M1 macrophages.In vitro experiments demonstrated that silencing NCAPD2 suppressed LUAD cell proliferation,migration,invasion,epithelial-mesenchymal transition(EMT),and cell cycle progression.Conclusions:In summary,NCAPD2 may represent a promising prognostic biomarker and novel therapeutic target for LUAD.

Crystalline and amorphous metal sulfide composite electrode materials with long cycle life:Preparation and performance of hybrid capacitors

Crystalline@amorphous NiCo_(2)S_(4)@MoS_(2)(v-NCS@MS)nanostructures were designed and constructed via an ethylene glycol-induced strategy with hydrothermal synthesis and solvothermal method,which simultaneously realized the defect regulation of crystal NiCo_(2)S_(4) in the core.Taking advantage of the flexible protection of an amor-phous shell and the high capacity of a conductive core with defects,the v-NCS@MS electrode exhibited high specif-ic capacity(1034 mAh·g^(-1) at 1 A·g^(-1))and outstanding rate capability.Moreover,a hybrid supercapacitor was assembled with v-NCS@MS as cathode and activated carbon(AC)as anode,which can achieve remarkably high specific energy of 111 Wh·kg^(-1) at a specific power of 219 W·kg^(-1) and outstanding capacity retention of 80.5%after 15000 cycling at different current densities.

Summer Atmospheric Water Cycle under the Transition Influence of the Westerly and Summer Monsoon over the Yarlung Zangbo River Basin in the Southern Tibetan Plateau

This study compares the summer atmospheric water cycle,including moisture sources and consumption,in the upstream,midstream,and downstream regions of the Yarlung Zangbo River Basin in the southern Tibetan Plateau.The evolutions of moisture properties under the influence of the westerly and summer southerly monsoon are examined using 5-yr multi-source measurements and ERA5 reanalysis data.Note that moisture consumption in this study is associated with clouds,precipitation,and diabatic heating.Compared to the midstream and downstream regions,the upstream region has less moisture,clouds,and precipitation,where the moisture is brought by the westerly.In early August,the vertical wet advection over this region becomes enhanced and generates more high clouds and precipitation.The midstream region has moisture carried by the westerly in June and by the southerly monsoon from July to August.The higher vertical wet advection maximum here forms more high clouds,with a precipitation peak in early July.The downstream region is mainly affected by the southerly-driven wet advection.The rich moisture and strong vertical wet advection here produce the most clouds and precipitation among the three regions,with a precipitation peak in late June.The height of the maximum moisture condensation is different between the midstream region(325 hPa)and the other two regions(375 hPa),due to the higher upward motion maximum in the midstream region.The diabatic heating structures show that stratiform clouds dominate the upstream region,stratiform clouds and deep convection co-exist in the midstream region,and deep convection systems characterize the downstream region.

Life cycle assessment as a prospective tool for sustainable agriculture and food planning at a local level

Owing to the far-reaching environmental consequences of agriculture and food systems,such as their contribution to climate change,there is an urgent need to reduce their impact.International and national governments set sustainability targets and implement corresponding measures.Nevertheless,critics of the globalized system claim that a territorial administrative scale is better suited to address sustainability issues.Yet,at the subnational level,local authorities rarely apply a systemic environmental assessment to enhance their action plans.This paper employs a territorial life cycle assessment methodology to improve local environmental agri-food planning.The objective is to identify significant direct and indirect environmental hotspots,their origins,and formulate effective mitigation strategies.The methodology is applied to the administrative department of Finistere,a strategic agricultural region in North-Western France.Multiple environmental criteria including climate change,fossil resource scarcity,toxicity,and land use are modeled.The findings reveal that the primary environmental hotspots of the studied local food system arise from indirect sources,such as livestock feed or diesel consumption.Livestock reduction and organic farming conversion emerge as the most environmentally efficient strategies,resulting in a 25%decrease in the climate change indicator.However,the overall modeled impact reduction is insufficient following national objectives and remains limited for the land use indicator.These results highlight the innovative application of life cycle assessment led at a local level,offering insights for the further advancement of systematic and prospective local agri-food assessment.Additionally,they provide guidance for local authorities to enhance the sustainability of planning strategies.

Exploring the mechanical behavior and microstructure of compacted loess subjected to dry-wet cycles and chemical contamination

Due to climatic factors and rapid urbanization,the soil in the Loess Plateau,China,experiences the coupled effects of dry-wet cycles and chemical contamination.Understanding the mechanical behavior and corresponding microstructural evolution of contaminated loess subjected to dry-wet cycles is essential to elucidate the soil degradation mechanism.Therefore,direct shear and consolidation tests were performed to investigate the variations in mechanical properties of compacted loess contaminated with acetic acid,sodium hydroxide,and sodium sulfate during dry-wet cycles.The mechanical response mechanisms were investigated using zeta potential,mineral chemical composition,and scanning electron microscopy(SEM)tests.The results indicate that the mechanical deterioration of sodium hydroxidecontaminated loess during dry-wet cycles decreases with increasing contaminant concentration,which is mainly attributed to the thickening of the electrical double layer(EDL)by Nat and the precipitation of calcite,as well as the formation of colloidal flocs induced by OH,thus inhibiting the development of large pores during the dry-wet process.In contrast,the attenuation of mechanical properties of both acetic acid-and sodium sulfate-contaminated loess becomes more severe with increasing contaminant concentration,with the latter being more particularly significant.This is primarily due to the reduction of the EDL thickness and the erosion of cement in the acidic environment,which facilitates the connectivity of pores during dry-wet cycles.Furthermore,the salt expansion generated by the drying process of saline loess further intensifies the structural disturbance.Consequently,the mechanical performance of compacted loess is sensitive to both pollutant type and concentration,exhibiting different response patterns in the dry-wet cycling condition.

Meiotic nuclear divisions 1 suppresses the proliferation and invasion of pancreatic cancer cells via regulating H2A.X variant histone

Introduction:Among all malignant tumors of the digestive system,pancreatic carcinoma exhibits the highest mortality rate.Currently,prevention and effective treatment are urgent issues that need to be addressed.Methods:The study focused on meiotic nuclear divisions 1(MND1),integrating data from the Gene Expression Profiling Interactive Analysis(GEPIA)database with prognostic survival analysis.Simultaneously,experiments at cellular level were employed to demonstrate the effect of MND1 on the proliferation and migration of PC.The small-molecule inhibitor of MND1 was used to suppress the migration of PC cells by knocking down MND1 using small interfering RNA(siRNA)in Patu-8988 and Panc1 cell lines.Results:The results of Cell Counting Kit-8 indicated that the suppression of MND1 resulted in a decrease in cell proliferation.Wound healing and Transwell assays revealed that MND1 knockdown reduced cell migration and invasion.Flow cytometry revealed that inhibiting MND1 hindered the cell cycle.Furthermore,MND1 could stimulate the proliferation,migration,and invasion of Patu-8988 and Panc1 cells by increasing the expression of MND1.Notably,MND1 had a positive effect on H2AFX expression in PC cells.Elevated MND1 expression suggests the low overall survival rate of individuals diagnosed with PC.Conclusion:These findings suggest that MND1 has the potential to be a gene with the ability to accurately diagnose and treat PC.

Bicycle-related traumatic injuries: a retrospective study during COVID-19 pandemic

BACKGROUND:This study aimed to review bicycle-related injuries during the COVID-19 pandemic to assist with reinforcement or implementation of new policies for injury prevention.METHODS:This is a retrospective descriptive analysis of injuries sustained during cycling for patients 18 years old and above who presented to Singapore General Hospital from January to June 2021.Medical records were reviewed and consolidated.Descriptive analyses were used to summarize patient characteristics,and differences in characteristics subgrouped by triage acuity and discharge status were analyzed.RESULTS:The study included 272 patients with a mean age of 43 years and a male predominance(71.7%).Most presented without referrals(88.2%)and were not conveyed by ambulances(70.6%).Based on acuity category,there were 24(8.8%)Priority 1(P1)patients with 7 trauma activations,174(64.0%)and 74(27.2%)P2 and P3 patients respectively.The most common injuries were fractures(34.2%),followed by superficial abrasion/contusion(29.4%)and laceration/wound(19.1%).Thirteen(4.8%)patients experienced head injury and 85 patients(31.3%)were documented to be wearing a helmet.The majority occurred on the roads as traffic accidents(32.7%).Forty-two patients(15.4%)were admitted with a mean length of stay of 4.1 d and 17(6.3%)undergone surgical procedures.Out of 214(78.7%)discharged patients,no re-attendances or mortality were observed.In the subgroup analysis,higher acuity patients were generally older,with higher proportions of head injuries leading to admission.CONCLUSION:Our study highlights significant morbidities in bicycle-related injuries.There is also a high proportion of fractures in the young healthy male population.Injury prevention is paramount and we propose emphasizing helmet use and road user safety.

The Impact of Network Topologies and Radio Duty Cycle Mechanisms on the RPL Routing Protocol Power Consumption

The Internet of Things(IoT)has witnessed a significant surge in adoption,particularly through the utilization of Wireless Sensor Networks(WSNs),which comprise small internet-connected devices.These deployments span various environments and offer a multitude of benefits.However,the widespread use of battery-powered devices introduces challenges due to their limited hardware resources and communication capabilities.In response to this,the Internet Engineering Task Force(IETF)has developed the IPv6 Routing Protocol for Low-power and Lossy Networks(RPL)to address the unique requirements of such networks.Recognizing the critical role of RPL in maintaining high performance,this paper proposes a novel approach to optimizing power consumption.Specifically,it introduces a developed sensor motes topology integrated with a Radio Duty Cycling(RDC)mechanism aimed at minimizing power usage.Through rigorous analysis,the paper evaluates the power efficiency of this approach through several simulations conducted across different network topologies,including random,linear,tree,and elliptical topologies.Additionally,three distinct RDC mechanisms—CXMAC,ContikiMAC,and NullRDC—are investigated to assess their impact on power consumption.The findings of the study,based on a comprehensive and deep analysis of the simulated results,highlight the efficiency of ContikiMAC in power conservation.This research contributes valuable insights into enhancing the energy efficiency of RPL-based IoT networks,ultimately facilitating their widespread deployment and usability in diverse environments.