Multi-Objective Optimization of the Ultrasonic Scalpel Rod and Tip with Improved Performance:Vibration Frequency,Amplitude,and Service Life

Ultrasonic scalpel design for minimally invasive surgical procedures is mainly focused on optimizing cutting performance.However,an important issue is the low fatigue life of traditional ultrasonic scalpels,which affects their long-term reliability and effectiveness and creates hidden dangers for surgery.In this study,a multi-objective optimal design for the cutting performance and fatigue life of ultrasonic scalpels was proposed using finite element analysis and fatigue simulation.The optimal design parameters of resonance frequency and amplitude were determined.By setting the transition fillet and keeping the gain structure away from the node position to enable the scalpel to have a high service life with excellent cutting performance.The frequency modulation method of setting the vibration node bosses at the node position and setting the vibration antinode grooves at the antinode position was compared.Then,the mechanism of the influence of various design elements,such as tip,shank,node position,and antinode position,on the resonance frequency,amplitude,and fatigue life of the ultrasonic scalpel was analyzed,and the optimal design principles of the ultrasonic scalpel were obtained.The proposed ultrasonic scalpel design was confirmed by simulations,impedance measurements,and liver tissue cutting experiments,demonstrating its feasibility and enhanced performance.This research introduces innovative design strategies to improve the fatigue life and performance of ultrasonic scalpels to address an important issue in minimally invasive surgery.

Effectiveness of Short Message Service Support on Adherence to Chemotherapy Treatment among Patients Attending Cancer Treatment Facilities in Kenya

Introduction: Cancer is a chronic debilitating disease that unnerves patients, communities, and nations. At some point in cancer patient’s disease experience, chemotherapy is used, and the patient is expected to adhere to treatment to improve survival and quality of life. Methods: This multisite Cluster Randomized Trial (CRT) evaluated the effectiveness of mobile phone Short Message Service (SMS) support on the adherence to treatment schedules among adult cancer patients in Kenya. Data was collected using questionnaires. Ethical approvals were obtained from relevant Ethical Review Boards (ERBs). Results: The mean adherence was 83%. There was a significant difference between treatment arms in relation to the adherence. The intervention arm had a higher mean adherence difference, M = 3.913, 95% CI 2.632-5.193, t (402) = 6.006, p ≤ 0.001), with Cohen’s d = 0.60. Although not significant, (χ2dd = 0.151, df = 1, p = 2.064), more women were perfect adheres than males. Perfect adherers were satisfied with SMS support (χ2dd = 7.620, df = 1, p = 0.06), were in the intervention arm (χ2dd = 22.942, df = 1, p ≤ 0.001), and had trust in the care provider (χ2dd = 10.591 p ≤ 0.001). SMS support was not significant in the multivariate analysis but had an estimated effect size of 0.958 (z = 1.424, p = 0.154, CI = 0.242-3.781), indicating that mean adherence was slightly better in the presence of the intervention. Conclusions: SMS-support intervention has demonstrated superiority in influencing adherence. Further, health system-related factors have a significant influence on the adherence to chemotherapy treatment. Interventions to re-design health systems that are responsive to unmet care needs of cancer patients must be explored. .

Experimental study of water aging on asphalt during service life of pavements

In order to further simulate the real condition of pavements during the service life,moisture is considered in long-term aging tests based on the existing researches about thermal aging and oxidation aging of asphalt.Water is injected into the pressure aging vessel（PAV）to simulate the aging process during the service life.The performance-based strategic highway research program（SHRP）parameters G/sinδ and S（t）are adopted to evaluate the high-temperature properties and low-temperature properties of the aged asphalt,respectively.The Thailand 90# asphalt,the modified Thailand 90# asphalt and the Shell 70# asphalt are used in the test.It is found that the moisture has a significant influence on parameter G/sinδ when combined with heat and oxygen,so water aging makes high-temperature performance decay more seriously.But the low-temperature performance does not change remarkably after water aging.Since the influences of temperature,oxygen and water are taken into account in the PAV test,the accuracy of asphalt aging tests can be improved and the long-term aging process of asphalt pavement can be exactly simulated.

Master Curve Method of Cumulative Damage for Prediction of Service Life

Aim To study the theory and method for the prediction of service life of solid rocket propellant grain. Methods With the aid of discontiguous diagnostic technology and method of accumulated damage using accelerated aging or heat air oven, the aging isotherms for void content versus aging time were determined. According to the principle of time temperature equivalence the viscoelastic master curve for the prediction of service life were obtained. Results and Conclusion The service life of HMX CMDB solid rocket propellant grain were obtained. Because the critical storage life is measured, the accuracy of predicting the service life of the grain has been increased greatly.

Fatigue Life Prediction under Service Load Considering Strengthening Effect of Loads below Fatigue Limit

Lightweight design requires an accurate life prediction for structures and components under service loading histories. However, predicted life with the existing methods seems too conservative in some cases, leading to a heavy structure. Because these methods are established on the basis that load cycles would only cause fatigue damage, ignore the strengthening effect of loads. Based on Palmgren-Miner Rule （PMR）, this paper introduces a new method for fatigue life prediction under service loadings by taking into account the strengthening effect of loads below the fatigue limit. In this method, the service loadings are classified into three categories： damaging load, strengthening load and none-effect load, and the process for fatigue life prediction is divided into two stages： stage I and stage II, according to the best strengthening number of cycles. During stage I, fatigue damage is calculated considering both the strengthening and damaging effect of load cycles. While during stage II, only the damaging effect is considered. To validate this method, fatigue lives of automobile half shaft and torsion beam rear axle are calculated based on the new method and traditional methods, such as PMR and Modified Miner Rule （MMR）, and fatigue tests of the two components are conducted under service loading histories. The tests results show that the percentage errors of the predicted life with the new method to mean life of tests for the two components are –3.78% and –1.76% separately, much lesser than that with PMR and MMR. By considering the strengthening effect of loads below the fatigue limit, the new method can significantly improve the accuracy for fatigue life prediction. Thus lightweight design can be fully realized in the design stage.

Service Life Prediction of Lining Concrete of Subsea Tunnel under Combined Compressive Load and Carbonation

Qingdao Jiaozhou Bay subsea tunnel is the second self-built tunnel in China with the designed service life over 100 years.The durability of lining concrete are one of an important factors to determinate the service life of tunnel.Considering the main environmental loads and mechanical loads of subsea tunnel,the durability properties of lining concrete under combined action of compressive load and carbonation has been studied through the critical compressive load test,accelerated carbonation test,natural carbonation test and capillary suction test.The tests results show that critical compressive load apparently accelerates the carbonation and deteriorates the anti-permeability of concrete.Under the combined action of critical compressive load and carbonation,the durability of lining concrete decreases.Based on the carbonization life criteria and research results,for the high-performance concrete with proposed mix ratio,the predicted service life of lining concrete for Jiaozhou bay subsea tunnel is about 80 years which fails to reach the required service life.It is necessary to adopt other measurements simultaneously to improve the durability of lining concrete.

Reliability-based service life prediction of existing concrete structures under marine environment

Chloride-induced corrosion of the reinforcement is considered as one of the major mechanisms resulting in the reduction of structural resistance of reinforced concrete structural elements located in marine and other aggressive environments. A study of reinforced concrete structures located at the Fangcheng dock in the Beibu Gulf port, China, was present. The result from field survey indicates that the concrete cover depth and chloride diffusion coefficient fit best normal distribution and lognormal distribution, respectively. The service life of structure is about 55 a, while initiation time is 45 a. Sensitivity analysis indicates that the most influential factor of the structure service life prediction is concrete cover, followed by diffusion coefficient, diffusion decay index, critical chloride concentration, surface chloride concentration, current density and localized pitting corrosion. Finally, the effects of diffusion decay index and critical chloride concentration on structure service life prediction are discussed.

Improvement of Service Life of Small Furnace Covers on 150 t Refining Ladles

The factors restricting the life of the refining furnace cover were introduced,including the airflow erosion of the refining dust removal system,the melting loss caused by the arc radiation of the electrode,the chemical erosion and penetration of slag and gas,and the condition of refining slag.The improvement measures are adjusting the material of the small furnace cover from corundum to chrome corundum,using a large shaking table to vibrate,optimizing the size design of the small furnace cover,and appropriately thickening the weak areas in the triangular area.The average service life of the refining furnace cover has been increased from one week to two months,reaching 4 maintenance cycles,which meets the needs of the refining production.

Effects of Operation Conditions on Service Life of Ladle Lining

Effects of operation conditions such as ladle temperature, remining time of molten steel, slag basicity, slag oxidation, slag viscosity , vacuum treatment, ultra-high temperature, gas blowing and stirring, intermittent operation, and different refining equipment on service life of ladle lining refractories were researched. The following conclusions are drawn ： （1） molten steel temperature rising, remaiaing time prolonging, slag oxidation ability enhancing, slag viscosity and basicity decreasing can aecelerate the corrosion of ladle lining ; （2） ultra-high temperature and vacuum treatment of ladle not only acceler- ate the fusion corrasion of ladle lining, but also make the carbon containing refractories react forming gases leading to more corrosion, so carbon containing refractories are not stdtable.for the smelting conditions of long term vacuum treatment and ultra-high temperature, especially carbon containing refractories added with conventional additives such as A1 and Si powders ; （ 3 ） argon blowing does not accelerate the corrosion of ladle lining obvioasly, but oxygen blowing does; （4） the corrosion degree of refractories varies with the refining equipment, and the service life of ladle lining decreases according to a certain proportion with the refining ratio increasing.

Study on the mechanical properties and service life of H13 mandrels

The microstructures and mechanical properties of H13 mandrels made by Baosteel and foreign companies were investigated in this study. Based on the comparison research, the processes were optimized, such as steelmaking, heat treatment and multiple forging processes. The quality of Baosteel mandrels was greatly improved by increasing the homogenizing of an annealing temperature and refining processes. The results of the pilot trial showed that the average number of piercing steel tubes for Baosteel mandrels was over 3000 ,which reached the level of imported mandrels.

Service Life Design for Concrete Engineering in Marine Environments of Northern China Based on a Modified Theoretical Model of Chloride Diffusion and Large Datasets of Ocean Parameters

In this study,through experimental research and an investigation on large datasets of the durability parameters in ocean engineering,the values,ranges,and types of distribution of the durability parameters employed for the durability design in ocean engineering in northern China were confirmed.Based on a modified theoretical model of chloride diffusion and the reliability theory,the service lives of concrete structures exposed to the splash,tidal,and underwater zones were calculated.Mixed concrete proportions meeting the requirement of a service life of 100 or 120 years were designed,and a cover thickness requirement was proposed.In addition,the effects of the different time-varying relationships of the boundary condition(Cs)and diffusion coefficient(Df)on the service life were compared;the results showed that the time-varying relationships used in this study(i.e.,Cscontinuously increased and then remained stable,and Dfcontinuously decreased and then remained stable)were beneficial for the durability design of concrete structures in marine environment.

Sociodemographic Predictors of Health-Related Quality of Life and Healthcare Service Utilisation among Young Refugees in South Australia

Although refugee adolescents and children are recognised as a health risk population, few studies have explored their Health-related Quality of Life (HRQOL). The present study investigated 1) the sociodemographic predictors of HRQOL such as ethnicity, trauma exposure, and length of residency in Australia in a multiethnic paediatric population with refugee experiences and 2) the relationship between mental healthcare utilisation and HRQOL. Method: Participants were 458 adolescents and children, aged 4 - 17 years, living in South Australia. Parents provided data across the sample and adolescents also completed questionnaires. Overall HRQOL and its composite functional dimensions were assessed using the Paediatric Quality of Life (PedsQL) instrument. Questions from the Child and Adolescent Component of the Australian National Survey of Mental Health and Wellbeing were used to assess service utilisation. Results: Migration region/ethnicity predicted better HRQOL as well as physical, emotional and psychosocial functioning for both children and adolescents. African youths indicated higher HRQOL than those from the former Yugoslavia and the Middle East/South Asia respectively. Pre-migration trauma exposure was associated with lower HRQOL;and longer stay in Australia was related to lower emotional functioning in children. There was a negative association between healthcare service utilisation and PedsQL scores, with participants accessing services demonstrating lower HRQOL. Conclusion: Using more rigorous methods, future research is needed to investigate additional sociodemographic predictors of HRQOL, and protective/risk factors that impact on HRQOL of young refugees.

Changes in functions,forms,and locations of lead during its anthropogenic flows to provide services

Knowledge of the changes in a material’s function, form, and location during the transfer and transformation of materials to generate human services will improve our understanding of how humanity interacts with the environment and of how services are formed by human activities. We compared lead’s anthropogenic and biogeochemical cycles and found that the services, pathways, and changes in form requiring the most attention. We traced lead through its life cycle and identified the changes in its functions, forms, and locations by examining technology and engineering information. Lead ore and scrap were the two main anthropogenic sources of lead. When lead provides human services, its main functions included the storage and delivery of electricity, anti-corrosion treatments, and radiation protection; the main forms of lead in these products were Pb, PbO2 and PbSO4, and the main location changed from lithosphere in central China to regions in eastern China.

A Semi-Mechanistic Model for Predicting the Service Life of Composite Coatings on VW63Z Magnesium Alloy

The application of Mg alloys is always accompanied by various coating technology, but a reliable model predicting the service life of coatings on Mg alloys is lacking but urgent. In this work, a semi-mechanistic model was proposed to predict the service life of plasma electrolytic oxidation (PEO) coating/electrophoretic coatings on a VW63Z Mg alloy;the model was decomposed into three parts: a first part depicting the degradation time of organic coating (L_(1)) and the diffusion time of electrolyte in the inorganic coating (L_(2)), respectively;a second part interpreting the breakdown of coatings due to the corrosion process (L_(3));a final part establishing an algorithm converting the accelerated tests into the real service environment (α);the effect of structural stress and dissimilar metal joints on the service life of coatings was also considered. Based on the ongoing accelerated experiments, the semi-mechanistic model could be able to predict the service life of both PEO coatings and composite coatings on VW63Z Mg alloy with a satisfiable precision.

Study on Strength and Life of Anisotropic Single Crystal Blade - Part I: Crystallographic Constitutive Models and Applications

The single crystal blade is one of the key technologies for improving the performance, durability and reliability of aero-engines and ground gas-turbine engines. However, the anisotropic mechanical properties of the single crystal material makes a great deal of difficulties on the development and the application of the single crystal blade, which is a challenge for the engineering application of the single crystal superalloy and the theoretic bases of the application. Some researches on the strength analysis and the life prediction of the anisotropic single crystal blade were carried out by the authors' research team. They are as follows. The crystallographic constitutive models for the plastic and the creep behaviors and the method of the rupture life prediction were established and verified. The tensile or the creep experiments for DD3 single crystal alloy with different orientations under different temperatures and different tensile rates or under different temperatures and different stress levels were carried out. The experimental data and the anisotropic properties at intermediate and high temperatures revealed by the experiments are significant for the application of the single crystal alloy. In addition, the experimental research for a kind of single crystal blade was also made. As the application of the researches the strength analysis and the life prediction were carried out for the single crystal blade of a certain aero-engine. In this part, the constitutive models and their applications are described, and the experimental research work will be described in part II.

The impact of hearing impairment and noise-induced hearing injury on quality of life in the active-duty military population:challenges to the study of this issue

The objectives of this review were to 1)summarize the available evidence on the impact of hearing loss on quality of life(QOL)among U.S.active-duty service members,2)describe the QOL instruments that have been used to quantify the impact of hearing loss on quality of life,3)examine national population-level secondary databases and report on their utility for studying the impact of hearing loss on QOL among active-duty service members,and 4)provide recommendations for future studies that seek to quantify the impact of hearing loss in this population.There is a lack of literature that addresses the intersection of hearing impairment,the military population,and quality of life measures.For audiological research,U.S.military personnel offer a unique research population,as they are exposed to noise levels and blast environments that are highly unusual in civilian work settings and can serve as a model population for studying the impact on QOL associated with these conditions.This review recommends conducting a study on the active-duty service member population using a measurement instrument suitable for determining decreases in QOL specifically due to hearing loss.

Application of TCM constitution in lifetime health maintenance

Healthy full life cycle has become an important national strategy,which indicates that attention needs to be given to human health throughout the life course.The full life cycle includes the whole process of conception and birth,development,growth,aging,and death,which has been recorded in Yellow Emperor's Canon of Medicine.From the perspective of traditional Chinese medicine (TCM) constitution theory,the TCM constitution focuses on the life process in a continuous evolution based on individual development at different phases or stages from infancy to senility.The development of TCM constitution is beneficial in accumulating the theoretical and practical experience for promoting the application of TCM constitution health service into the full life cycle,and providing theory,technique and method for TCM health service in the full life cycle,as well.Through this review,we've found that TCM constitution has being widely used for clinical practice,but still needs further improvement.

Effect of precise nursing service mode on postoperative urinary incontinence prevention in patients with prostate disease

BACKGROUND Patients with benign prostatic disease often experience detrusor morphological changes and dysfunction.In severe cases,it leads to bladder detrusor dysfunction,resulting in dysuria,frequent urination,urgent urination,incomplete urination,and other symptoms including renal function injury.An operation to restore normal urination function and to control postoperative complications,as far as possible,is the most common method for benign prostatic disease.AIM To observe the effect of precise nursing service mode on postoperative urinary incontinence prevention in patients with prostate disease.METHODS In total,130 patients diagnosed with benign prostatic disease,from January 2018 to June 2021,in our hospital,were selected and divided into observation and control groups according to their treatment options.Sixty-five cases in the control group were given routine nursing mode intervention and 65 cases in the observation group received precise nursing service mode intervention.The intervention with the observation group included psychological counseling about negative emotions,pelvic floor exercises,and post-hospital discharge care.The complications of the two groups were counted,and the general postoperative conditions of the two groups were recorded.The urinary flow dynamics indexes of the two groups were detected,and differences in clinical international prostate system score(IPSS)and urinary incontinence quality of life questionnaire(I-QOL)scores were evaluated.RESULTS Postoperative exhaust time(18.65±3.23 h and 24.63±4.51 h),the time of indwelling catheter(4.85±1.08 d and 5.63±1.24 d),and hospitalization time(8.78±2.03 d and 10.23±2.28 d)in the observation group were lower than in the control group.The difference was statistically significant(P<0.05).After the operation,the maximum urinary flow rate(Qmax)increased(P<0.05),the residual urine volume(RUV)decreased(P<0.05),and the maximum closed urethral pressure(MUCP)was not statistically significant(P>0.05)compared to pre-operation.The Qmax of the observation group was higher than that of the control group,while the RUV was lower than that of the control group.There was no significant difference in MUCP between the observation and control groups(P>0.05).The I-QOL score of the two groups improved(P<0.05),and the IPSS decreased(P<0.05).After the operation,the I-QOL score of the observation group was higher than that of the control group,and the IPSS was lower than that of the control group(P<0.05).There were no significant differences in the incidence of urethral injury(1.54%and 3.08%),bladder spasm(0.00%and 1.54%),and secondary bleeding(1.54%and 4.62)between the observation and control groups(P>0.05).CONCLUSION The precise nursing service mode can reduce the incidence of postoperative urinary incontinence in patients with prostate disease,thus improving postoperative urodynamics and rehabilitation,and quality of life.

Research on whole life cycle carbon emission model of typical buildings

Based on the theory of life cycle assessment(LCA),this article analyzes the influence factors on carbon emissions from residential buildings.In the article,the life cycle of residential buildings has been divided into five stages:building materials production period,construction period,operation and maintenance period,demolition period,and solid waste recycle and disposal period.Based on this definition,the authors provide a theoretical model to calculate carbon emissions of residential building life cycle.In particular,the factor of human activities was introduced in the calculation of carbon emissions from the buildings.Furthermore,the authors put forward a model for calculation with the unit of carbon emissions for per-capita living space.