Analysis Of Parameters Research Articles

Desert-oasis evolutionary process in the Tarim Basin since ∼ 2.2 ka B.P. during the late Holocene and their environmental implications

Oases, serving as ideal locations for human settlements in arid regions, exhibit extreme sensitivity to regional climatic fluctuations. Consequently, the oasis deposition sediments play a pivotal role in the study of regional paleoenvironmental changes and the exploration of prehistoric human-environment interactions. The YSD and STM sections, both typical aeolian-lacustrine sections located at the edge of the Tarim Basin, were investigated in this study. By analyzing optically stimulated luminescence (OSL) dating results and grain-size proxy indicators, the environmental evolution patterns in the Tarim Basin since approximately 2.2 ka BP were reconstructed. Additionally, the parametric end-member analysis on the grain-size data was conducted to explore the environmental significance revealed by each end-member. The research findings indicate that: (1) ∼ 2.2–1.8 ka B.P., sediment morphology and grain-size parameters indicate that the climate in the Tarim Basin recorded by the STM section was relatively dry, with rivers gradually receding and frequent sand-drift activities. During the development of the YSD section (∼1.67–1.5 ka B.P.), the environmental conditions in the Tarim Basin transitioned to a relatively humid phase, with the Yarkand River experienced multiple episodes of natural diluvial deposition. The grain-size data of two sections both comprise five sedimentary dynamic components, serving as sensitive indicators of regional humidity conditions and winter monsoon intensity. (2) The oasis development in the Tarim Basin during the late Holocene (particularly refers to between ∼ 2.2 ka B.P. and ∼ 1.4 ka B.P.) exhibits a significant positive correlation with temperature records. (3) Environmental changes and human activities jointly regulate the spatial and temporal distribution and number of archeological sites during the development of both sections. However, the dominance of the two factors varied across different historical periods.

Improvement of titanium film uniformity by magnetron sputtering with electromagnetic coil design

A novel magnetron assembly based on a combination of permanent magnet and adjustable electromagnetic coil is proposed for improved uniformity of the magnetron sputtering deposition process. The design of the magnetron sputtering system containing a rotating substrate and an off-axis arranged magnetron. A numerical framework has been developed to describe the evolution of the plasma density and distribution of sputtered particles. Specifically, the finite element method (FEM) was used to calculate the magnetic field and to model the magnetron sputtering discharge, and binary-collision Monte Carlo method was used to determine the transport of sputtered atoms to the substrate. Through parametric analyses, it was found that increasing the substrate-to-target distance, gas pressure, and coil current intensity benefits the uniform distribution of particles. The condition where the off-axis displacement of the magnetron effectively enhances uniformity. A strategy for optimizing deposition uniformity by combining adjustable current with an off-axis magnetron arrangement was proposed, which reduce the non-uniformity of film thickness by 77.6 % compared to the traditional fixed magnetic field model.

Analysis of the Wear Parameters and Microstructure of High-Carbon Steel in Order to Identify Its Tribological Properties

Alloyed high-carbon steels are materials primarily intended for components operating under conditions of intense tribological wear. The carbides present in the microstructure of these materials significantly contribute to improving the wear resistance of such alloys. However, changes in the morphology of these precipitates can considerably alter the wear rate, leading to a deterioration in the properties of the materials. Therefore, this study aims to analyze the influence of several factors on the tribological wear of alloyed high-carbon steel. The research included friction tests under various load conditions and different sliding paths. Additionally, the samples were subjected to heat treatment to change the morphology of the observed precipitates. The tribological tests were conducted in a block-on-ring configuration under dry friction conditions. The tribological tests were analyzed statistically using analysis of variance (ANOVA). The results of the statistical analysis indicated that the primary factor influencing the observed differences between the samples was the heat treatment time of the material. Additionally, there were no significant statistical differences when pressure and friction path were varied. These findings, in conjunction with the SEM studies, allowed for the evaluation of the wear mechanism. The results demonstrated that, within the adopted tribological system, no alterations in the wear mechanism were observed with changes in test parameters. The observed differences in wear properties between the samples were found to be related to their heat treatment. The heat treatment resulted in alterations to the particle size distribution, with the annealing of the material at an elevated temperature leading to the dissolution of finer particles within the material. An increase in the average diameter of the carbide present in the material was observed to improve the wear resistance of the alloy tested.

Research on the Deformation Control Measures during the Construction Period of Super High-Rise Buildings with an Asymmetric Plan

Based on the Guangzhou Business Center project, a typical super high-rise building with an asymmetric plan, taking the construction speed, closure time of mega braces and belt trusses as influencing factors, a parametric analysis on its lateral and vertical deformations, as well as the maximum stress of key structural members was conducted. The analysis results indicated that the construction speed had a relatively small impact on the deformation and the maximum stress of key members. However, synchronous closure of belt truss compared with the delayed closure would result in smaller horizontal and vertical deformation differences, as well as the stress of belt truss. Meanwhile, the closure timing of the mega braces had little influence on the vertical deformation difference and the stress of belt truss. And the earlier the closure, the smaller the horizontal drift ratio, the greater the maximum stress of the mega braces. Further, deformation control measurements were brought forward. On the one hand, FEM simulation was carried out according to the above construction suggestions. On the other hand, real-time monitoring was also used. Finally, by comparing both results, proposed construction deformation control measures and simulation methods were verified.

Experimental and Numerical Study on the Performance of Steel–Coarse Aggregate Reactive Powder Concrete Composite Beams with Uplift-Restricted and Slip-Permitted Connectors under Negative Bending Moment

An innovative form of steel–concrete composite beam, the steel–coarse aggregate reactive powder concrete (CA-RPC) composite beam with uplift-restricted and slip-permitted (URSP) connectors, is introduced in this paper. The aim is to enhance the cracking resistance under negative bending moments, which is a difficult problem for traditional composite beams, and to make the cost lower than using ordinary reactive powder concrete (RPC). An experimental investigation of the behavior of six specimens of simply supported steel–CA-RPC composite beams with URSP connectors under negative bending moments is presented in this paper. The test results validated that the cracking load of steel–CA-RPC composite beams could be approximately three times that of the ordinary steel–concrete composite beams while the bearing capacity and stiffness are almost the same. A numerical model, using the concrete damaged plasticity (CDP) model to simulate the behavior of the CA-RPC material, was proposed and successfully calculated the overall load–displacement relationship of the composite beams with sufficient accuracy compared with the experimental results, and the distribution of cracks and the failure mode of the beams could also be captured by this model. Furthermore, a parametric analysis was carried out to find out how the application of prestress, CA-RPC, and URSP connectors could affect the cracking resistance of the composite beams, and the results indicated that using CA-RPC and prestress made the main contributions and that the usage of URSP could boost the effect of the other two factors. The plastic resistance moment of the beams was also compared with the calculation results using the methods introduced in Eurocode 4, and it was proved that the calculation results were lower than the experimental results by approximately 10%, which meant that the method was reliable for this kind of composite beam.

Effect of exercise intensity on growth performance, serum biochemistry parameters, liver antioxidant capacity, and intestinal health of common carp (Cyprinus carpio) in recirculating aquaculture system

This study examined the impact of different exercise intensities on the growth performance, serum biochemistry, liver antioxidant capacity, and intestinal health of common carp (Cyprinus carpio). A total of 270 common carp with an initial weight of 63.91 ± 1.45 g were divided into three groups: a Sustained Exercise group [SE, 1 bl/s (body length per second), 24 h/day], an Intermittent Exercise group (IE, 1 bl/s, 8 h/day), and a Control group (CG, 3 cm/s) for a 90-days experiment. The results demonstrated that exercise substantially improved weight gain rates in common carp. Analysis of serum biochemical parameters revealed that increased exercise intensity significantly reduced levels of triglycerides (TG), total cholesterol (T-CHO), and glucose (GLU) (P < 0.05). Post-exercise evaluations also indicated significant reductions in immune-related markers, including lysozyme (LZM), aspartate aminotransferase (AST), and alanine aminotransferase (ALT). Regarding liver antioxidant enzyme activities, the levels of glutathione peroxidase (GSH-Px) and total superoxide dismutase (T-SOD) were significantly higher in the IE group relative to the CG group (P < 0.05). Conversely, the total antioxidant capacity (T-AOC) was significantly lower in the SE group than in the CG group (P < 0.05). In terms of intestinal health, intermittent exercise significantly reduced the expression of pro-inflammatory cytokine genes and increased gut villus length. Additionally, an increase in exercise intensity significantly enhanced the activities of intestinal amylase and lipase. Analysis of the intestinal microbiota through 16S rRNA sequencing revealed that intermittent exercise fostered a more diverse microbial community. Specifically, with an increase in exercise intensity, the relative abundance of Fusobacteriota rose, while those of Firmicutes decreased. At the genus level, the abundances of Cetobacterium and Aeromonas increased, contrasting with declines in Muribaculaceae, Bacteroides, and Escherichia-Shigella. PICRUSt2 functional predictions suggest that exercise might modify the intestinal environment by increasing the prevalence of pathogenic bacterial communities, potentially leading to intestinal damage and adversely affecting the physiological state of the intestine. An observed increase in riboflavin metabolism in the SE group likely contributed to its markedly improved growth performance relative to other groups. In summary, sustained exercise at 1 bl/s improved growth and intestinal digestive enzyme activity in common carp. However, it also induced stress, potentially compromising physiological health, liver function, and immune strength, consequently elevating the risk of disease. These findings provide crucial insights for optimizing growth and physiological health in common carp and other fish species in recirculating aquaculture systems through exercise.

Identification and Application of Wave Field Characteristics of Channel Waves in Extra-Thick Coal Seams

Channel wave seismic activity often occurs with thin and medium-thick coal seams being the main target layer. To address the problem of channel wave applicability detection in extremely thick coal seams, the propagation and identification characteristics of channel waves remain the focus of research. Therefore, this paper takes the in-seam wave exploration of a 27 m extremely thick coal seam as an example and uses the staggered mesh finite difference method to construct a three-dimensional medium model for numerical simulation. An analysis of the physical parameters of coal and rock, along with the dispersion characteristics of channel waves in extra-thick coal seams, is utilized, through the Zoeppritz equation and the total reflection propagation method, to calculate the imaging. We found the following: (1) The dispersion areas and weak dispersion areas along the detection direction are extremely thick coal seams. (2) There are apparent channel waves in extra-thick coal seams, with a waveform similar to body waves; the length of the wave train is shorter than that of the conventional channel wave, and the arrival time can be estimated accurately. The amplitude of the apparent channel wave is affected by the degree of dispersion, with lower attenuation and higher resolution. The characteristic of total reflection in extremely thick coal seams is that the incident angle is equal to the critical angle, and the dispersion characteristics are weak. (3) The channel waves with weak dispersion characteristics in extra-thick coal seams are mainly Love-type waves.

Analysis of Erythrocyte Parameters in Multiple and Long-Term Blood Donors from Northern Pomerania (Poland)

Background/Aims: Assessment of the levels of vital blood parameters in donors is essential to evaluate their health status, ensure their suitability for donation, preserve the integrity of the circulatory system, and facilitate comprehensive health monitoring. The aim of our study was to analyse the levels of haemoglobin, haematocrit, erythrocyte count, MCV, MCH, and MCHC in 12 groups of first-time donors and experienced donors of both sexes at the John Paul II Regional Blood Donation and Treatment Centre in Słupsk, northern Poland. The donors were divided into three age groups (18-30 years, 31-45 years, and 46-65 years). Methods: Using MANOVA multivariate significance tests, we examined the main effects of donor-related factors (age, sex, donor stage) on morphological blood parameters to evaluate different haematological parameters, such as Hb, Ht, RBC, MCV, MCH, and MCHC, and identified statistically significant relationships between all variables. Results: The multivariate analysis of these three main factors showed that the variation in haemoglobin (Hb) levels accounted for 46% of the explained dependence in this statistical model. In particular, approximately half of the variability in the multivariate statistical analysis was attributed to the role of Hb and haematocrit (Ht). In addition, the β-coefficient values for Hb and Ht were statistically higher in relation to donor sex and donor type (single versus repeat). These β-coefficient values from our data represent the strength and direction of the relationship between the haematological parameters (Hb and Ht) and the specific donor characteristics. A higher β-coefficient indicates a stronger influence of donor sex and donor type on these parameters, suggesting that these factors contribute significantly to the variation in the Hb and Ht levels. Based on our results, the comprehensive analysis of the entire statistical model of metabolic biomarkers revealed the following hierarchy: Hb &gt; Ht &gt; MCHC &gt; MCV &gt; RBC &gt; MCH. The results obtained showed strong statistical relationships, as indicated by the high values of the key statistical indicators in our analysis. The coefficient of determination (R²) showed that the model explained a significant proportion of the variance in the data, while the F-test statistic confirmed the significance of the predictors. Conclusion: These strong statistical dependencies provided a clear justification for selecting this model over others, as it effectively represented the underlying relationships within the data. These statistics help to assess how well the model matches the actual data, thereby helping to reduce the risks associated with blood donation, optimise donor safety, and maintain the quality and efficiency of blood transfusion services.

A multi-node thermodynamic model on temperature-vacuum swing adsorption (TVSA) for carbon capture: Process design and performance analysis

The adsorption technology plays a significant role in the carbon capture domain for mitigating the CO2 emissions, whereas the heterogeneous character is presented in practical adsorption process. In this study, a multi-node thermodynamic model is established for temperature-vacuum swing adsorption (TVSA) considering the end non-uniform adsorption. It shows superior performance for the assessment of practical TVSA cycle compared with lumped model. Through the influence analysis of different operation parameters based on multi-node model, specific exergy consumption increases from 41.6 to 62.4 kJ/mol caused by simultaneous drop of heat consumption and lift of work consumption as feed pressure raises from 1.0 to 3.0 bar. Exergy efficiency ranges between 13.8 % and 15.0 % as CO2 concentration increases from 10 % to 20 %. However, those under ppm-level are below 0.86 %, presenting the higher exergy consumption but lower desorption capacity represented for direct air capture. The heat consumption of front half part of adsorption bed is 39.7 % higher than the latter one, proving the potential cascaded desorption of subzone heating is superior for reducing the energy consumption. Furthermore, exergy consumption is lifted due to enhancement of work consumption of vacuum pump as vacuum pressure reduces from 1.0 to 0.02 bar, resulting exergy efficiency drops from 19.6 % to 13.4 %.

Computationally effective machine learning approach for modular thermal energy storage design

This research presents an innovative approach that integrates computational fluid dynamics (CFD) and machine learning (ML) for the design and optimization of thermal energy storage (TES) systems. Heat discharging parametric analyses conducted using CFD serve as the basis for training ML models, including linear regression, K-nearest neighbor (KNN) regression, gradient boost regression (GBR), XGBoost, LightGBM, and neural network (NN). NN emerges as the most suitable for predicting time-dependent variations of concrete and heat transfer fluid (HTF) temperatures. The trained ML models offer an efficient alternative to traditional CFD simulations, enabling the prediction of temperatures in concrete thermal energy storage (CTES) modules under varying inlet conditions, velocities, and time. Leveraging these ML models, the research demonstrates the design of modular CTES cascaded systems with multiple modules in series and parallel configurations, significantly reducing computational cost and time by over 99% compared to full-scale CFD simulations. For instance, in predicting 4-hour time-dependent thermal behavior, CFD takes 97 s per data point and 238,500 s for a single module, compared to ML models’ 16-20 ms per data point and around 290 s per module, indicating their efficiency and scalability in predicting thermal discharge, especially for modular CTES system design and optimization. ML models also demonstrate computational efficiency for designing CTES systems involving multiple modules, taking approximately 765 s - 1047 s for various CTES system configurations, indicating their effectiveness over CFD in predicting thermal discharge for modular CTES systems. The integration of CFD and ML provides a streamlined workflow for designing and optimizing CTES systems, reducing computational efforts, cost, and time. Moreover, this workflow can be updated with additional training data to implement it for unique modular designs with different conditions. Such a generalization of this ML-based approach makes it applicable to a wide range of thermal energy storage designs and geometries, offering a promising avenue for future research and development in the field of thermal energy storage.

Evidence for landslides in Sisyphi Cavi (Noachis Terra, Mars): Slope evolution and role of endogenous preparatory factors

The surface of Mars is characterized by the presence of numerous gravity-induced processes and mass movements with greatly variable sizes and peculiarities. Detailed geomorphological studies have recently made it possible to identify many landslide-like landforms along the slopes bordering pits of Sisyphi Cavi in Noachis Terra, the southern hemisphere of Mars. These pieces of evidence are generally characterized by extended trenches, sometimes associated with uphill- or downhill-facing scarps. In this study, the gravity-induced processes observed in this region of Mars, and especially those present in a closed pit of the eastern sector, are described for the first time. A quantitative stress-strain analysis was performed, and it excludes a type of deformation process that could invoke creep processes (“viscosity-driven”) but rather favors instability induced by stress-perturbations in the slope more concentrated over time (“force-driven”). In particular, we performed a parametric analysis on both viscosity and stiffness parameters of the materials involved. It demonstrates that the time necessary for the rheological evolution of deformational processes associated with the observed landforms are compatible with genesis of short-term instabilities. This finding has significant implications for the origin of the depressed forms within and close to the study area, which are characterized by unstable slopes present at their edges. It is therefore not necessary to invoke the role of “viscosity-driven” creep processes to explain the origin of the shapes associated with the observed gravity-induced slope instabilities. The reported results drive towards a new interpretative scenario of morphological evolution of the widespread pits in the study area in terms of efficiency of endogenous processes (such as hypabyssal magmatism) which characterize the studied area of Mars, even if it is not possible to exclude the role of exogenous processes.

Thermodynamic analysis of an advanced adiabatic compressed air energy storage system integrated with a high-temperature thermal energy storage and an Organic Rankine Cycle

Advanced adiabatic compressed air energy storage (AA-CAES) system has drawn great attention owing to its large-scale energy storage capacity, long lifespan, and environmental friendliness. However, the performance of the air turbine during the discharging process is limited by the low temperature of the compression heat. Thus, this study proposes an integrated AA-CAES system incorporating high-temperature thermal energy storage and an Organic Rankine Cycle (ORC). The high-temperature thermal energy storage is introduced to heat the discharging compressed air to enhance the air turbine performance, and the Organic Rankine Cycle is integrated to utilize the waste heat. Notably, two preheaters are deployed in a special tandem to recover the heat from the air exiting the turbine and the water exiting the hot water tank, respectively. This paper develops a thermodynamic model to simulate the proposed system, assessing the effects of heat storage temperature, ambient temperature, and inlet conditions of the air turbine on performance metrics, including exergy efficiency and exergy destruction. The simulation results indicate that, compared to thermal oil and Hitec salt, employing solar salt as the heat storage medium for the solar thermal collection and storage unit yields the best performance. The energy storage efficiency, roundtrip efficiency, exergy efficiency, exergy conversion coefficient, and energy storage density of this system are 115.6 %, 65.7 %, 78 %, 79.4 %, and 5.51 kWh/m3, respectively. Exergy analysis reveals that the exergy efficiency of interheaters (IH) is the lowest at 76.7 %, while air turbines (ATBs) exhibit the highest exergy efficiency at 91.2 %. Moreover, due to the irreversible processes of compression, expansion, and throttling, ATBS, compressors, and throttle valves collectively contribute to an exergy destruction rate as high as 79.2 %. The parameter analysis demonstrates that low ambient temperature, high inlet temperature, and high inlet pressure of the air turbine enhance energy storage performance.

Seismic performance of friction damped posttensioned steel frame equipped with SMA strands

The post-tensioned friction dissipating (PTFD) connection for steel frames has drawn significant attention from researchers due to its excellent seismic performance. A simplified numerical algorithm suitable for modeling the SMA strands is proposed. The simplified numerical model of the SMA-PTFD is established. Parametric analysis is performed based on hysteresis analysis and transient dynamic analysis to reveal the influence of SMA strands on the seismic performance of SMA-PTFD frames. The changing rule of seismic response of SMA-PTFD frames, along with the fmax for SMA strands and the Fmax for the friction device, is systematically investigated. The value of the objective function can be reduced by about 50 % when the fmax is increased from 1 kN to 13 kN. The fundamental frequency is 1.25 Hz for three analyzed conditions. The value of the second frequency is significantly affected by Fmax. The values of the second frequency are 1.5 Hz, 1.58 Hz, and 1.42 Hz. The characteristics of seismic response, including displacement and cable force, are deeply studied. The seismic response is also investigated in the frequency domain. The results presented in this work reveal the collaborative energy dissipation mechanism of the friction device and SMA strands.

Design, fabrication and vibration characteristics of a novel composite auxetic structure embedded with resonators

With the rapid development of shipbuilding and aerospace industries, the mechanical performance requirements for structures are becoming increasingly demanding. Conventional vibration reduction structures cannot meet the requirements for lightweight, high load capacity, low frequency and broadband vibration reduction. Therefore, it is necessary to consider new structural topologies and material systems. Inspired by the lightweight and high strength characteristics of composite materials, the negative Poisson's ratio characteristics and the locally resonating phononic crystal, the carbon fiber composite auxetic structure embedded with resonators is proposed. Embedded resonators within composite auxetic structures can be strategically positioned to introduce gaps, thereby enhancing the vibration damping performance. The basic auxetic structure is prepared by simpler methods including molding and bonding, and the outer shell of resonator is made by 3D printing technology. The method enables the design of appropriate outer shell based on various cavity types within the structure, ensuring a stable connection between resonators and the structure itself. The range of the band gap can be predicted based on the negative effective mass. Vibration behavior and band gap characteristics of the structure are proved through vibration experiments and numerical simulations. It is revealed that the structure can generate local resonant band gaps at lower frequencies. Meanwhile, the coupling relationship between the auxetic structure and the resonator makes an impact to the band gap range. Therefore, the proposed structure can meet the required multi-functional integrated performance requirements. Furthermore, the parametric analysis is carried out, and the relevant conclusions can provide theoretical guidance for designing porous composite structures with effective low-broadband vibration reduction capabilities.

A theoretical model for the load-transfer analyses of load distributive compression anchor integrating DSC-based interface nonlinear model

An innovative anchorage technology named load distributive compression anchor (LDCA) has recently been employed in a multitude of geotechnical engineering. The anchoring structure comprises multiple anchor bodies, thereby overcoming the bearing defects associated with conventional load-concentrated anchors and providing superior bearing performance. The complex structural configuration of LDCA considerably complicates the process of load-transfer theoretical modeling. A lack of relevant studies from theoretical solution perspective is yet evident in previous works. In this paper, a theoretical model was proposed for the load-transfer analyses of LDCA, of which the soil-anchor interface mechanical behavior was specially characterized by a disturbed state concept (DSC)-based nonlinear model. The mechanical simulation for the connections in different anchor bodies was incorporated into the theoretical analysis framework through the utilization of finite difference method. Three groups of 3D finite element (FE) models were established to simulate the load-transfer behaviors of LDCAs with different numbers of anchor bodies. The theoretical calculations agree well with the FE numerical results and the in-situ pullout test data, thereby confirming the applicability of the load-transfer theoretical model. The axial force and interface shear stress distributions, as well as the bearing capacity for LDCAs, were discussed based on theoretical calculations and FE simulations. Sensitivity analysis of several key design parameters was conducted to investigate their effects on the bearing capacity of LDCAs. The findings achieved in this study can provide insights into the understanding of the load-transfer behaviors of LDCA, and contribute to the bearing performance evaluation.

Temporal Statistical Analysis and Retrospective Assessment of Mortality Rate in the United States from 1999 to 2018

Objectives: To retrospectively examine the mortality trend in the USA from 1999 to 2018 using a basic statistical model while examining multiple variables. The inferential and descriptive statistical tools will be prioritized to elucidate the mortality of both years in simple terms. Methods: We conducted a retrospective observational descriptive analysis of data on the 10 leading causes of death in the United States by age, race, and sex over 2 decades (1999 to 2018). The data in this report are based on information from all death certificates filed in the 50 states and the District of Columbia. The causes of death are classified by the International Classification of Diseases, 10th Revision (ICD–10), which is ranked according to the number of deaths (Cause-of-death statistics are based on the underlying cause of death). This report supplements “Deaths: Final Data for 2020,” the National Center for Health Statistics’ annual report of final mortality statistics. SPSS (statistical package for social sciences) version 29 Software in Excel sheet was used to analyze the generated datasets. Descriptive and inferential (parametric and non-parametric) analyses were used. The statistically significant relationships and assumptions were made using the chi-square/t-test, Kruskal-Wallis, and Fischer's exact tests with the significance level set at p ≤ 0.05. The analysis and determination of the level of agreement between the initial diagnosis and findings from the new analysis done. Results: The proportion of age-adjusted death rates of the heart (such as coronary artery disease) account for the highest proportion of 24%, while Malignant neoplasms (cancers) represent 23%, Chronic lower respiratory diseases contribute 6%, Unintentional injuries (accidents) also play a significant role, accounting for 5% of deaths. The regression analysis reveals a strong and statistically significant relationship between the number of causes in females and males. There was a high death rate of around 60 years in 1999 and a consistent decline over the years, reaching below 40 by 2018, with a 15/100,000 death fluctuation mark. Asian or Pacific Islander has the lowest age adjustment value of 8762.4, American Indian or Alaska Native, Hispanic, or Latino(11673.2), Black or African American, Hispanic, or Latino (12992.1), White, not Hispanic or Latino(15457.1), Black or African American (15708.2), Hispanic or Latino(19624.1), American Indian or Alaska Native, not Hispanic or Latino (16287.9).Asian or Pacific Islander, not Hispanic or Latino( 8791.3), and 99.2% of the variability in the dependent variable and standard error of 6.7240. Conclusions: Cardiovascular death remains the most common cause of death, with a significant decrease in the death rate from 1999 to 2018 due to improved health care and the provision of measures to improve health care. The regression analysis reveals a strong and statistically significant relationship between the number of causes in females and males. Therefore, based on the results, the number of causes in females strongly predicts the number of causes in males.

Statistical analysis of parameters affecting Legionella and total cell growth in premise plumbing systems within buildings: A field study based on an empirical data set

During the storage and distribution of water in buildings, the excessive growth of pathogens can deteriorate the quality of drinking water. This study aims to investigate the factors influencing this growth and propose technical measures for prevention. The analysis is based on an empirical data set comprising 1361 samples from 204 domestic premise plumbing systems. In 14 systems, ultrafiltration plants were installed as microbiological barriers. Legionella cultivation and flow cytometry were used to determine microbiological properties. The study identified elevated total cell counts in tapping valves and pipe end lines in numerous premise plumbing systems, indicating prolonged water stagnation prior to sampling, which facilitates microbiological growth. Higher contamination rates were observed in these systems, with peripheral taps often being contaminated in lieu of the entire system. These systems were classified as microbiologically unstable due to the relevantly higher total cell numbers at hot water taps compared to the hot water tank (>25%). Furthermore, these systems exhibited a Legionella contamination rate that was 22.3% higher than in microbiologically stable systems. In some cases, peripheral contaminations may not accurately represent the entire premise plumbing system. Increasing the discard volume during sampling from 1 L to 3–5 L could provide more precise results during standard testing. Legionella species were primarily detected in the first 1 L of water after tap activation. Additionally, statistically significant relationships were observed between direct temperature and total cell number, as well as between the presence of ultrafiltration and total cell numbers at cold water taps.

Cooling effect and parameter analysis of applying heat insulation layer to tunnel regionalization in construction period based on geothermal level

The construction of high geothermal tunnels presents significant difficulties due to the abnormal rock temperature gradients, including designing a reasonable and cost-effective insulation layer as well as effective cooling measures. In this study, the rock temperature distribution, environmental temperature, and lining surface temperature of the tunnel during the construction period were analyzed through field surveys. A numerical simulation model considering ventilation and heat transfer dynamics was established based on the geothermal measurements and construction characteristics of this tunnel. After validating the 3D numerical model, the effects of installing heat insulation layers according to geothermal levels on the tunnel temperature field control were investigated. Additionally, the impacts of different insulation layer thermal conductivities (λi), ventilation air volume (Wa), and duct thermal conductivities (λd) were analyzed. The results indicate: (1) The comparison of temperature fields in tunnels with insulation layers, which is applied in the range of the rock temperature above 50 °C and without insulation layers was made. The temperature near the excavation face (TAm-1) decreases by up to 0.3% (0.5 °C), tunnel environment temperature with insulation layer applied (TAm-2) decreases by up to 4.2% (2.1 °C), the secondary lining temperature (TSec-lining) decreases by up to 10.5% (4.6 °C), and the wind temperature of air duct outlet (TAir-duct) decreases by up to 0.7% (0.5 °C). (2) The length of the insulation layer increases to the full length of the tunnel, TAm-1 continues to decline by only 0.4°C, TAm-2 by 0.5 °C, TSec-lining by 0.9 °C, and TAir-duct by 0.1 °C, which shows that it is the most economical and reasonable to apply the insulation layer only in the tunnel area where the rock temperature is higher than 50 °C. (3) As λi increases, both the tunnel environment and secondary lining temperatures exhibit linear increases, while increasing Wa and λi cause quadratic decreases and increases in tunnel temperature field parameters, respectively. (4) Range analysis of orthogonal experiments reveals that for tunnel temperature field impact level. For TAm-1, the significance order is Wa >λd >λi. And for TAm-2 and TSec-lining, the significance order is Wa >λi >λd, which can provide the more economical scheme for the insulation layer design and cooling schemes in the high ground temperature tunnel.

Objective Analysis of Traditional Chinese Medicine Syndrome Differentiation of Patients With Diabetes and Prediabetes: Protocol for a Nonrandomized, Exploratory, Observational Case-Control Study Using Digitalized Traditional Chinese Medicine Diagnostic Tools.

Diabetes and prediabetes are diagnosed differentially by Western and Chinese medicine. While Western medicine uses objective laboratory analysis of biochemical parameters to define the severity of diabetes and prediabetes, Chinese medicine uses a comprehensive approach that integrates observation, inquiry, pulse palpation, and tongue diagnosis. The medical information collected is then categorized into different syndromes. However, traditional methods of pulse and tongue diagnoses used to determine syndrome differentiation are highly subjective and skill dependent. This study aims to identify the gap in conventional traditional Chinese medicine (TCM) diagnostic techniques for syndrome differentiation analysis using contemporary diagnostic devices. We devised a protocol for a nonrandomized, exploratory, observational case-control study with equal allocations in 5 arms to investigate the syndrome differentiation of diabetes and prediabetes. We hypothesize that the TCM syndrome differentiation of diabetes and prediabetes in the tropical climate may differ from that defined based on the Chinese demographic. We also speculate that the high-frequency spectral energy may reflect a difference in pulse wave intensity and density between the healthy and diabetes groups. A total of 250 eligible participants will be equally assigned to 1 of 5 arms (healthy or subhealthy, prediabetes, diabetes, prediabetes with hypertension and dyslipidemia, and diabetes with hypertension and dyslipidemia). Participants aged 21-75 years, of any sex or race, and have been diagnosed with diabetes (fasting plasma glucose [FPG] of 7 mmol/L, or 2-hour plasma glucose [2hPG] of 11.1 mmol/L) or prediabetes (impaired FPG of 6.1-6.9 mmol/L, or impaired glucose tolerance with an 2hPG of 7.8-11 mmol/L) will be included. The Health Evaluation Questionnaire, Physical Activity Questionnaire, sugar intake assessment, Constitution in Chinese Medicine Questionnaire, radial pulse diagnosis, and tongue diagnosis will be performed in a single visit. ANOVA for continuous data and chi-square tests of independence will be used for categorical data assessments, with a level of P<.05 considered significant. The recruitment is in progress. We anticipate that the study will conclude in June 2025. As of July 15, 2024, we have enrolled 140 individuals. To the best of our knowledge, this is the first study to use contemporary TCM diagnostic instruments to map expert and empirical knowledge of TCM to its scientific equivalents for the purpose of evaluating the syndrome differentiation of diabetes. We designed this protocol with the exploratory goal to examine objectively the syndrome differentiation of patients with diabetes and those with prediabetes using TCM diagnostic technologies. The data collected and evaluated under standardized conditions using these contemporary diagnostic devices will exhibit a higher degree of stability, hence yielding dependable and unbiased results for syndrome differentiation. Thus, our findings may potentially increase the accuracy of identification, diagnosis, treatment, and prevention of diabetes and prediabetes through a system of targeted treatment. ClinicalTrials.gov NCT05563090; https://clinicaltrials.gov/ct2/show/NCT05563090. DERR1-10.2196/56024.

Time-varying cost modeling and maintenance strategy optimization of plateau wind turbines considering degradation states

Plateau wind power has great potential in reducing carbon emissions; however, compared with other renewable energy, its economics still need to be improved. As an effective approach to enhance its economic feasibility, maintenance strategy optimization aims to reduce maintenance costs per kilowatt-hour and extend equipment lifespan. This paper proposes a multi-objective optimization model for the maintenance decision-making of plateau wind turbines that considers the degradation state. It incorporates: i) modeling the maintenance process of plateau wind turbines by combining time-based and state-based methods; ii) considering the time-varying maintenance costs in complex environments; and iii) employing a multi-objective optimization method to find the optimal strategy that meets maintenance requirements. The complexity considered in the model mainly includes the randomness of the operating duration for each equipment state, the temporal variability of equipment distribution and installation costs, and the uncertainty in maintenance effectiveness. The proposed optimization method is applied to a wind farm in the Yunnan-Guizhou Plateau, China.The results indicate that traditional maintenance strategies underestimate maintenance costs and equipment lifespan losses. Compared with conventional maintenance strategies, this method can reduce equipment maintenance costs by 24.07 % and extend its operating life by 11.58 %. Additionally, this paper has conducted a series of parametric analyses to enhance the generalization performance of the model. The proposed method effectively addresses the economic issues of plateau wind turbine maintenance and provides a valuable decision-making tool for guiding the long-term maintenance of wind turbines in complex environments.