Effect Of Loading Research Articles

Effects of higher dietary acid load: a narrative review with special emphasis in children.

Metabolic effects of high diet acid load (DAL) have been studied for years in adults, although only recently in children. Contemporary diets, especially those of Western societies, owe their acidogenic effect to high animal-origin protein content and low contribution of base-forming elements, such as fruits and vegetables. This imbalance, where dietary acid precursors exceed the body's buffering capacity, results in an acid-retaining state known by terms such as "eubicarbonatemic metabolic acidosis," "low-grade metabolic acidosis," "subclinical acidosis," or "acid stress". Its consequences have been linked to chronic systemic inflammation, contributing to various noncommunicable diseases traditionally considered more common in adulthood, but now have been recognized to originate at much earlier ages. In children, effects of high DAL are not limited to growth impairment caused by alterations of bone and muscle metabolism, but also represent a risk factor for conditions such as obesity, insulin resistance, diabetes, hypertension, urolithiasis, and chronic kidney disease (CKD). The possibility that high DAL may be a cause of chronic acid-retaining states in children with growth impairment should alert pediatricians and pediatric nephrologists, since its causes have been attributed traditionally to inborn errors of metabolism and renal pathologies such as CKD and renal tubular acidosis. The interplay between DAL, overall diet quality, and its cascading effects on children's health necessitates comprehensive nutritional assessments and interventions. This narrative review explores the clinical relevance of diet-induced acid retention in children and highlights the potential for prevention through dietary modifications, particularly by increasing fruit and vegetable intake alongside appropriate protein consumption.

Load-Dependent Characteristics of Cruciate-Retaining and Posterior-Stabilized Total Knee Arthroplasty: A Biomechanical Study.

Increased load bearing across the patellofemoral and tibiofemoral articulations has been associated with total knee arthroplasty (TKA) complications. Therefore, the purpose of this study was to quantify the biomechanical characteristics of the patellofemoral and tibiofemoral joints and simulate varying weight-bearing demands after posterior cruciate ligament-retaining (CR) and posterior-stabilized (PS) TKAs. Eight fresh-frozen cadaveric knees (average age, 68.4 years; range, 40-86 years) were tested using a custom knee system with muscle-loading capabilities. The TKA knees were tested with a CR and then a PS TKA implant and were loaded at 6 different flexion angles from 15° to 90° with progressively increasing loads. The independent variables were the implant types (CR and PS TKA), progressively increased loading, and knee flexion angle (KFA). The dependent variables were the patellofemoral and tibiofemoral kinematics and contact characteristics. The results showed that at higher KFAs, the position of the femur translated significantly more posterior in CR implants than in PS implants (36.6 ± 5.2 mm and 32.5 ± 5.7 mm, respectively). The patellofemoral contact force and contact area were significantly greater in PS than in CR implants at higher KFAs and loads (102.4 ± 12.5 N and 88.1 ± 10.9 N, respectively). Lastly, the tibiofemoral contact force was significantly greater in the CR than the PS implant at flexion angles of 45°, 60°, 75°, and 90° KFA, the average at these flexion angles for all loads tested being 246.1 ± 42.1 N and 192.8 ± 54.8 N for CR and PS implants, respectively. In this biomechanical study, CR TKAs showed less patellofemoral contact force, but more tibiofemoral contact force than PS TKAs. For higher loads across the joint and at increased flexion angles, there was significantly more posterior femur translation in the CR design with a preserved posterior cruciate ligament and therefore significantly less patellofemoral contact area and force than in the PS design. The different effects of loading on implants are an important consideration for physicians as patients with higher load demands should consider the significantly greater patellofemoral contact force and area of the PS over the CR design.

The effect of occlusal loading on secondary tooth eruption: An experimental study using a rat model.

This study aimed to assess the impact of occlusal loading on secondary tooth eruption and to determine the extent to which altering the occlusal loading influences the magnitude of secondary eruption through an experimental rat model. The present sample consisted of 48 male Wistar rats. At the onset of the experiment, 24 rats were 4 weeks old (young rats) and 24 rats were 26 weeks old (adult). Within each age group, the rats were further divided into two equal subgroups (12 rats each), receiving either a soft- or hard-food diet for the 3-month duration of the experiment. The primary outcome was the tooth position changes relative to stable references in the coronal plane by evaluating the distance between the mandibular first molars and the inferior alveolar canal. Microcomputed tomography scans were taken from all rats at three standardized intervals over the 3-month study period. Descriptive statistics were calculated by age and diet over time, and the evolution of the outcomes were plotted by age and diet over time. Longitudinal data analysis via generalized estimating equations was performed to examine the effect of age, diet and time on the primary outcomes. Secondary tooth eruption was observed in all age groups (young and adult) regardless of diet consistency (soft or hard food). In young rats, the secondary eruption was greater in the animals fed a soft diet than those fed a hard diet. In adult rats, minimal difference in secondary tooth eruption were found between different diet consistencies. Occlusal loading influences secondary tooth eruption in teeth with an established occlusal contact. The quantity of eruption in growing rats is higher when occlusal loading is less, providing a certain amount of secondary tooth eruption occurs. This difference, however, is not evident in adult rats, at least during the given 3-month time frame.

Attenuation Effect of Azolla spp. on Lambda-Cyhalothrin Toxicity to Aquatic Organisms.

Wetlands play a crucial role in providing valuable ecosystem services, including the removal of various pollutants. In agricultural basins, wetlands are exposed to agrochemical loads. This study aims to assess the attenuation effect of the ubiquitous macrophyte Azolla spp. on the toxicity of lambda-cyhalothrin to sensitive aquatic organisms. An indoor mesocosm experiment was conducted to compare the concentration of lambda-cyhalothrin at different time points after pesticide application in vegetated and unvegetated treatments, including a control without pesticide addition. Toxicity tests were performed throughout the experiment on three organisms: a fish (Cnesterodon decemmaculatus), a macroinvertebrate (Hyalella curvispina), and an amphibian (Boana pulchella). The results demonstrated that lambda-cyhalothrin concentration and toxicity in water were significantly lower in the Azolla spp. treatment. Furthermore, the half-life of lambda-cyhalothrin decreased from 1.2days in the unvegetated treatment to 0.4days in the vegetated treatment. The vegetated treatment also resulted in a significantly lower mortality rate for both H. curvispina and C. decemmaculatus. However, no mortality was observed in B. pulchella for any of the treatments. Sublethal effects were observed in this organism, such as lateral bending of the tail and impairment of the ability to swim, which were attenuated in the vegetated treatment. We conclude that Azolla spp. can effectively reduce the concentration and toxicity of lambda-cyhalothrin, suggesting its potential use in farm-scale best management practices to mitigate the effects of pesticide loads from adjacent crops.

Explainable highway performance degradation prediction model based on LSTM

With the dense and huge highway network in China, the highway maintenance management system has become the most concerned issue for Chinese highway managers in recent years. Therefore, based on the highway network in Guizhou Province of China, this paper established the semi-rigid asphalt pavement performance multi-output Long Short-Term Memory (LSTM) prediction model with regional applicability, including Pavement Surface Condition Index (PCI), Pavement Rutting Depth Index (RDI), Pavement Riding Quality Index (RQI) and Pavement Skidding Resistance Index (SRI) and the hyperparameters of the model were optimized by Bayesian optimization algorithm and the casual analysis of the model was conducted based on SHapley Additive exPlanations (SHAP), providing a reference for China's highway network-level preventive maintenance decision-making. The results prove that the established model can effectively predict the performance of the following year through the data of the previous two years. The established model has a better comprehensive prediction effect in comparison to similar multi-output models. The average coefficient of determination (R2) of the four prediction indexes can reach 0.823. Besides, the prediction effect among the indexes is stable and multiple pavement performance indexes can be effectively and reliably predicted at the same time. In addition, the contribution of input feature variables to output is quantified based on SHAP. According to quantified the contribution, the association relationship of the neural network model is set-valued mapped to the causality relationship in the post hoc. The input feature variables with the main contribution are extracted for causal analysis. The causal analysis shows that the degradation of the four pavement performances all have obvious time memory characteristics and have significant differences, but their pavement performance degradation is the result of nonlinear changes caused by the coupling effects of traffic load, road age, climate, and pavement structure.

A Coupled Effect of Eccentric Loading and Upward Seepage on Collapse Settlement of Strip Footings on Reinforced Sand

A Coupled Effect of Eccentric Loading and Upward Seepage on Collapse Settlement of Strip Footings on Reinforced Sand

Kinetics and Kinematics of the Push Press, Push Jerk, and Split Jerk.

Abstract Soriano, MA, Jiménez-Ormeño, E, Lake, JP, McMahon, JJ, Gallo-Salazar, C, Mundy, P, and Comfort, P. Kinetics and kinematics of the push press, push jerk, and split jerk. J Strength Cond Res 38(8): 1359–1365, 2024—The aim of this study was to explore the kinetics and kinematics across incremental loads with the push press (PP), push jerk (PJ), and split jerk (SJ). Eighteen resistance-trained men performed the 1 repetition maximum (1RM) tests (visit 1) 3–7 days before an incremental loading protocol (60, 75, and 90% 1RM) of the 3 exercises (visit 2). Kinetics and kinematics were derived from force-time data and compared using a repeated-measures analysis of variance with load and exercise as within-subject factors. Dependent variables for the biomechanics assessment were categorized as output (power and impulse), driver (force and work), and strategy (displacement and duration) metrics. The interrepetition reliability was assessed using the intraclass correlation coefficient and coefficient of variation. The PP, PJ, and SJ 1RM performance were 89.7 ± 15.4, 95.6 ± 14.4, and 103.0 ± 16.9 kg, respectively. Driver, strategy, and outcome metrics displayed moderate-to-excellent (intraclass correlation coefficient: 0.58–0.98) reliability with acceptable variability (% coefficient of variation: 2.02–10.00). Increased load resulted in significantly large increases in force, work, displacement, duration, power, and impulse (p < 0.001, = 0.534–0.903). Exercise selection had a significant and large effect on power, impulse, work, and force (p < 0.016, = 0.387–0.534). There was a significant and large effect of load × exercise interaction on work, displacement, and duration (p < 0.019, = 0.158–0.220). Practitioners are encouraged to use heavier loads (90 > 75 > 60% 1RM) during the SJ exercise to maximize output, driver, and strategy kinetics and kinematics.

Fabrication and characterization of optical filters from polymeric aerogels loaded with diamond scattering particles

We have developed a suite of infrared-blocking filters made by embedding diamond scattering particles in a polyimide aerogel substrate. We demonstrate the ability to tune the spectral performance of the filters based on both the composition of the base aerogel material and the properties of the scattering particles. We summarize the fabrication, optical modeling, and characterization of these filters. We investigate two polyimide base aerogel formulations and the effects of loading them with diamond scattering particles of varying sizes and relative densities. We describe a model for the filters’ behavior using a combination of Maxwell Garnett and Mie scattering techniques. We present optical characterization results for diamond-loaded aerogel filters with cutoff frequencies (50% transmittance) ranging between 2.5 and 15 THz, and confirm that the measured spectral performance is in agreement with our optical models. We also measure the filters’ refractive indices in the microwave and report findings in agreement with Maxwell Garnett model predictions (typically n<1.08).

Damage evolution and fracture characteristics of coal rock impacted by self‐excited pulse water jet under different stress loading conditions

AbstractIn this paper, based on smoothed‐particle hydrodynamics‐finite element method, numerical models of plunger squeezing water at a sinusoidal velocity were established to simulate self‐excited pulse water jet (SEPWJ). RHT constitutive model was adopted to describe the damage and failure of coal rock impacted by water jet. The morphological evolutions of broken pits and timeliness of rock‐breaking efficiency of SEPWJ and continuous water jet (CWJ) under the conditions with and without stress loadings were obtained and compared. The evolution laws of damage and stress inner coal rock induced by jet impact, and the failure mechanism were revealed. And the influences of different stress loading magnitudes on the fracture characteristics of coal rock were investigated. The results show that the morphologies of broken pits formed by self‐excited pulse jet undergo changes in a semi‐circular, U‐shaped, V‐shaped, and bullet shaped in sequence under the stress‐free loading condition. When applying one‐dimensional (1D) and 2D stress loadings, the shallow but wide broken pits with laminar main cracks along the stress loading direction and the inverted trapezoidal bowl broken pits are formed, respectively. With the increase of 1D stress, the depth and width of broken pits slightly decrease as a quadratic parabolic function and linearly increase, respectively. And the broken pit width and area both show an exponential slow decreasing trends with the increasing 2D stress. SEPWJ can induce higher stresses to cause the earlier occurrence of initial damage and the shorter duration of damage accumulation to coal rock than CWJ, which leads to a better rock‐breaking effect. The surface and deeper coal rock elements are broken mainly due to compressive shear stresses. The 2D stress loading delays the initial damage occurrence and prolongs the damage accumulation duration due to inhibitory effect of stress loading on jet impact.

Prestressed concrete continuous bridge girders: comparison of the Chinese and Southern African codes

To provide a reference for designers, taking a 30 m + 40 m + 30 m prestressed concrete continuous beam bridge as an example, this paper compares the differences between Chinese Codes and Southern African Codes in terms of load effect, prestressing requirements and design safety. The results show that the actual number of prestressed strands required by the Southern African Code in the mid-span section is 11.63 %-12.50 % larger than that required by the Chinese Code. The actual number of prestressed strands required by the Southern African Code in the fulcrum section is 16.33 %-30.00 % lower than that required by the Chinese Code. The safety margin factor of the section designed by the Southern African Code is higher than that of the Chinese Code, and has a higher safety reserve.

Analysis of Tall Building by using Different Dimensions Under Wind Load Effects

Abstract: The expense of land is increasing day by day because of rapid increase in the population whereas vegetation is diminishing, due to diminished vegetation contamination is expanded. In this Research paper, we analyze the various types of the dimensions of the building considering them side ratios too and the effect of windward forces on the building in mainly X and Z direction. This paper is about the study of four-building models as Dimensions (30m*30m), (40m*25m), (55m*20m), (80m*15m) having their horizontal Aspect ratios viz. 1, 1.6, 2.75 & 5.33 at an angle of 0 degrees. The height of the building is 90m. Therefore, the research is proceeding to balance out the structure from an increasingly affordable perspective. To find out the best performance and economical for the lateral wind-force resisting system of different models of 25 storey buildings are modelled in STAAD-PRO, assuming the site location as AGRA (Uttar Pradesh), India. For the different structural systems that are compared for minimum and maximum storey displacement, storey drift. The structural system used is prototype. The axial force, shear force, moment, and reactions at various windward sides are used to compare the best performance of the structure. Above all, wind forces in x- direction shows the adequate displacement and drift values when compared to z- direction but from the economic point of view Model-2 gives the satisfactory result from all the above.

EFFECT OF LIVE LOADS ON TOP SLAB OF CAST-IN-PLACE REINFORCED CONCRETE BOX CULVERTS

Reinforced concrete box culverts (RCBCs) designed according to old codes, using lighter truck weights (e.g., H15), may require posting when rated for current design and permit vehicles. When load ratings are calculated based on current AASHTO Specifications, they can be negatively affected by the conservative live-load attenuation through soil fill. This study evaluates the positive bending strains induced by live-load distribution through soil fill when load rating cast-in-place (CIP) RCBCs. Eighteen (18) single and multi-cell RCBCs in Kentucky were load tested and the effects of truck live loads analyzed. Fill heights, HF, varied from 0m (0ft) to 3.57m (11.7ft), clear cell spans, S, from 3.05m (10.0ft) to 6.71m (22.0ft), and culvert spans from 6.71m (22.0ft) to 18.59m (61.0ft). Field data were collected using strain gauges attached to the interior surfaces of culverts. Irrespective of how many cells the RCBCs had, strain variations with fill height in the top slabs were similar. At fill heights greater than 3.05m (10.0ft), maximum strains in the top slabs measured less than 10 microstrain, a value at which live-load effects are considered negligible. Combining live-load strains measured on the Kentucky culverts with ones from field tests in Missouri and Louisiana, a live-load tensile strain envelope is proposed to load rate the top slabs of RCBCs for positive bending when cell spans are less than 4.6m (15.0ft).

Stability analysis of an unreinforced concrete gravity dam

This project involved undertaking a stability analysis of an unreinforced concrete gravity dam. The stability assessment considered the 1 in 10 000 year and probable maximum flood events as well as the effects of ice and seismic loading, concluding that the above-ground dam section did not meet modern factors of safety and that further works would be required to stabilise the dam.

Creep damage evolution by cavity nucleation and growth considering the cavity closure under cyclic loading conditions

AbstractCreep damage assessment is crucial for ensuring the long‐term reliability of key components operating at high temperatures. However, the existing studies on creep damage are mainly focused on constant loading conditions, while the effect of cyclic loading, which is a common loading mode in practice, remains unclear. In this paper, a series of stress‐controlled cyclic creep tests on the Inconel 718 superalloy were performed to investigate the influence of cyclic loading on creep damage evolution. The ex‐situ microstructural analyses, including fracture surface observations and EBSD measurements, were conducted to reveal the damage mechanisms under cyclic creep conditions. Furthermore, a cavity nucleation and growth model that accounts for the additional cavity closure was developed for the healing effect of cyclic creep damage evolution. The prediction results were consistent with the experimental data of cavity nucleation life and experimental life within a factor of 2.

Effects of training load on heart rate variability and blood pressure in track and field athletes and skiers

BACKGROUND: Adaptation of human body to the harsh conditions of the European North remains a topic of ongoing interest, despite numerous studies on the subject. There is a need to study population groups whose daily activities involve physical activity in extreme northern conditions. One such group includes athletes who participate in endurance sports. For athletes engaged in cyclical sports, competitive activities becomes can be particularly demanding, requiring sustained physical exertion and maximum power generation. Training and competing in harsh conditions place significant strain on the body’s cardiovascular regulation mechanisms. Over time, this may result in detrimental structural and biochemical changes in the cardiovascular system. AIM: To identify the patterns of changes in heart rate regulation among track and field athletes and skiers after a training load. MATERIAL AND METHODS: Athletes from the Arkhangelsk region, including skiers and track and field athletes in the mass sports categories, who regularly compete in regional events, took part in the study. The studies took place in the medical offices of sports complexes, where the UPFT-1/30“Psychophysiologist” device was used to record and analyze cardiointervalograms. Blood pressure was recorded before and after training sessions using the Criticare System 8100H monitor. RESULTS: The initial variational span (VR) values of the duration of cardio intervals before exercise were slightly lower than the reference values in both the group of skiers and the group of athletes. At the same time, the mean square deviation (SD) values initially fell within normal range. Following the training load, both groups experienced a statistically significant decrease in SD and VR values, falling below the lower limit of the permissible range. Furthermore, spectral analysis of the cardiac intervals before exercise indicated a high level of neurohumoral regulation. After exercise, there was a statistically significant decrease in the initial values of TP in both groups, aligning with the average level of neurohumoral regulation. CONCLUSION: The results obtained in track and field athletes with a predominant anaerobic training load and skiers with a predominant aerobic load suggest that the training load of a predominantly aerobic nature may lead to less pronounced stress on the regulatory systems. This hypothesis was further supported by the results of the changes in blood pressure.

Modeling and Transmission Characteristics Study of a Resonant Underwater Wireless Electric Power Transmission System

Compared to the traditional wet-mate underwater power supply method, Magnetic Coupling Resonant Wireless Power Transfer (MCR-WPT) technology boasts advantages such as excellent insulation, high safety, and convenient operation, showing promising application prospects in the field of power supply for underwater vehicles and other mobile underwater devices. In order to explore the transmission characteristics of this technology underwater, this article first establishes a traditional mathematical model, and then modifies the underwater model through analysis of changes in coil self-inductance and mutual inductance, as well as the impact of eddy current losses. Using the modified mathematical model of the underwater MCR-WPT system, the transmission characteristics are analyzed, and simulations and experimental validations are performed using MATLAB R2022a software. In the study of frequency characteristics, it is found that the system operates optimally when both ends of the circuit work at the resonant state; that is, when finput = fresonance = 100 kHz, the output performance is at its best, and the optimal resonant frequency significantly improves power and transmission efficiency. When the input frequency is less than 87.3 kHz or greater than 122.9 kHz, the output power decreases to less than half of the maximum power. In the investigation of load effects, the optimal load for maximizing system output power was identified, but the load that maximizes transmission efficiency is different from this optimal load. This study provides strong theoretical support and guidance for improving the performance of underwater wireless power transmission systems.

A novel MOF-808 derived material for oxidative desulfurization: the synergistic effect of hydrophobicity and electron transfer.

A functionalized modified metal-organic framework material, T-MOF-808, was synthesized through hydrophobic modification with tetraethyl orthosilicate (TEOS) and chlorotrimethylsilane (TMCS). Then a supported oxidative desulfurization catalyst, [C12Py]3(NH4)3Mo7O24/T-MOF-808(s), was prepared by using a heteropoly acid ionic liquid as the active component. The prepared samples were characterized using FT-IR, XRD, SEM, TEM, XPS, etc. [C12Py]3(NH4)3Mo7O24/T-MOF-808(s) was used in the oxidative desulfurization of dibenzothiophene (DBT). At the same time, the effects of different loadings of the active component, oxygen sulfur ratios, reaction temperatures, and reaction time were also investigated. [C12Py]3(NH4)3Mo7O24/T-MOF-808-15%(s) could oxidize 100% of DBT in 40 min at 60 °C. Significantly, the catalyst exhibited no discernible decline in catalytic activity after 14 runs. In addition, the efficiency of sulfur removal was 85.76% in actual diesel oil. It was found that the cooperative impact of hydrophobic modification and electron transfer makes an important contribution to the high activity. The hydrophobic modification provides a novel approach for using MOF materials in the oxidative desulfurization process.

Durability of partially cured GFRP reinforcing bars in alkaline environments with or without sustained tensile load

Corrosion of steel reinforcing bars (rebars) in reinforced concrete structures can be addressed by using corrosion-resistant materials like Fiber-Reinforced Polymers (FRP). However, in France, FRP rebars are primarily restricted to temporary applications due to lack of comprehensive durability data. While numerous studies have explored FRP durability in alkaline environments, understanding the combined effect of alkali ions and sustained loading remains limited. Furthermore, the impact of incomplete matrix curing on the long-term performance of FRP rebars is limited.Accordingly, this paper investigates the durability of Glass FRP (GFRP) rebars exposed to alkali environments at varying temperatures. A batch of partially cured rebars was selected for this study, with part of them undergoing post-curing to investigate the effect of curing state on the ageing behaviour. Additionally, some partially cured specimens were subjected to combined sustained tensile loading at 20 % and 40 % of ultimate strength. Mechanical, physico-chemical and microstructural characterizations were conducted after various exposure durations. Results revealed that incomplete curing minimally impacted long-term tensile properties but significantly affected the interlaminar shear strength of aged rebars. Moreover, applying a combined load had little influence on residual properties at 20°C but led to rapid reduction in GFRP residual tensile strength at higher ageing temperatures (40 and 60°C).

Dimensionless analysis-based permeability model of reinforced concrete under tension

Water permeability of reinforced concrete is essential for transportation of ingress ions inside concrete structures. The coupling effect of permeability and loading presents a challenge for the experimental simulation of water-permeate reinforced concrete subjected to tension. This renders the development of the model based on dimensionless analysis, using a series of experimental tests from an innovative experimental system that allows simultaneous measurement of permeability and crack width. The experiments focused on both ordinary concrete and high strength concrete under tension. The relationship between permeability and variables such as deformation, diameter of rebars, tensile load, and crack width under tension was formulated through multiple regression analysis using the testing data. The load to deformation characteristics determines the permeability of the concrete under tension. The proposed model accounts for the influence of continuous loading on permeability, as demonstrated by the robust analysis and proposed yield effective point. The robust analysis demonstrates that the diameter of the rebar, load, and crack width exert minimal influence on the permeability of concrete at lower significance levels. However, permeability variations become pronounced from 0.5 threshold, with significant changes observed between 0.5 and 0.9 thresholds. The findings indicate a differential impact of the variables on the permeability of concrete under tension. The yield-effective points delineate the relationship between the rebar diameter, load, and crack-width on the permeability of concrete with a threshold of 0.5, 0.5, and 0.58, respectively. At a threshold of 0.78, higher permeability will occur in the concrete, attributed to the prevalence of deformation. This deformation highlights the parameters with the most significant influence on the permeability of concrete under tension. The robust analysis and yield effective point derivative are useful parameters to measure concrete permeability and evaluate the behavior of the permeability model under tension.

Production of sustainable polyester composite building material using industrial waste plastic core, hemp fabric, and shrimp shell powder: Effect of quasi-isotropic fiber stacking and particle loading

Production of sustainable polyester composite building material using industrial waste plastic core, hemp fabric, and shrimp shell powder: Effect of quasi-isotropic fiber stacking and particle loading