Principal Maximum Research Articles

Psychometric evaluation of the Chinese version of the nurse turnover intention scale: a translation and validation study

BackgroundGlobally, the issue of high nurse turnover rates is prevalent in China. The COVID-19 pandemic exacerbated the attrition rate of nurses. Turnover intention is the most reliable predictor of nurse turnover. However, there is currently a lack of proper evaluation tools in China. This study aimed to translate the Nurses Turnover Intention Scale (NTIS) into Chinese and examine the psychometric characteristics of the Chinese version of the NTIS among clinical nurses in China.MethodsApproximately 418 nurses were recruited from three tertiary general hospitals in Jiangxi, Guangdong, and Zhejiang provinces. This study used Brislin’s double-back translation, back-translation, and cross-cultural adaptation methods to translate the scale. Internal consistency, split-half reliability, and test-retest reliability were used to measure the reliability of the Chinese scale version. The validity of the Chinese scale version’s content was evaluated via the Delphi method. Exploratory and confirmatory factor analyses were carried out to evaluate the construct validity of the Chinese scale versions. In exploratory factor analysis, principal component analysis and maximum variance rotation method were used in this study. In the confirmatory factor analysis, Amos 24.0 software was used for analysis.ResultsThe NTIS in Chinese has ten elements: a Cronbach α coefficient of 0.864, a Cronbach α coefficient of 0.852∼0.903 for the three dimensions, and a split-half reliability and test-retest reliability of 0.878 and 0.960, respectively. This indicates that the Chinese version of the NTIS has good internal consistency and time stability. The scale-level content validity index (S-CVI) was 0.957, which indicated that the Chinese version of NTIS had good content validity. The total variance contribution rate was 79.055%, and three common factors were identified via exploratory factor analysis. The examined three-factor structure was confirmed by confirmatory factor analysis, which confirmed that all fit indices were appropriate.ConclusionsThe Chinese version of the NTIS was appropriate in terms of reliability and validity. This scale can be used to evaluate nurses’ turnover intention, and the outcomes can aid nurse management in designing training initiatives and implementing preventive measures to decrease nurse turnover.

Physical and numerical tests on adjustable–height structures of high–speed railway transition section

The disparity in stiffness and differential settlement between the subgrade and rigid structures can lead to track irregularities within transition sections, resulting in significant train vibrations and impacts. This study proposes an adjustable–height subgrade structure for transition sections by introducing a raft slab to divide the subgrade into upper and lower parts. When settlement occurs in the subgrade, the raft slab can be elevated using height–adjustment techniques to compensate for the settlement. To this end, large–scale physical model tests are conducted under train loading to verify the design's rationality and to elucidate the influence of settlement magnitude and train speed on the stress and deformation of the slab. The experimental results indicate that the maximum principal stress and maximum shear stress of the slab generally increase with settlement magnitude and train speed, and the area near the abutment end is the most unfavorable position for the deformation of the slab. However, it is still lower than the design compressive strength of the C40 concrete structure. Thus, the designed adjustable–height structure meets the load–bearing requirements under train loading. Additionally, a numerical simulation model of the adjustable–height structure is developed to investigate the recovery capabilities and stress distribution of the settled raft slab. The results indicated that whether the lifting operation employed linear load or equal load methods, the raft slab primarily endured compressive stress, and there is stress concentration at the lifting points. For the same lifting displacement, the linear load method proved to be more reasonable than the equal load method. These findings have significant practical and theoretical implications for ensuring the safe and smooth operation of high–speed railways, effectively addressing the post–construction settlement deformation control challenges in ballastless track transition sections.

A new scale for older resident satisfaction with residential integrated care in China: Development and validation

The factors that affect resident satisfaction with emerging residential integrated care for older people in China have been unclear due to a lack of validated instruments. Based on psychometric assessment procedures, we developed a new scale for older resident satisfaction with residential integrated care (SORSRIC). The scale was developed using a two-step process and a sample of 16 Chinese institutions and 333 residents. Exploratory and confirmatory factor analysis was used to evaluate reliability and validity. Principal component analysis and maximum variance methods were used to orthogonally rotate the items to extract seven factors. These were: resident expectations, perceived quality (physical care), perceived quality (mental care), perceived value, resident satisfaction, resident complaints, and resident loyalty. The CR value of each dimension of the pre-tested, formal scale was greater than 0.80, and the AVE value was greater than 0.50. This 24-item instrument showed good reliability and structural validity and can be applied to improve the experience and outcomes for older people in residential care.

Research on the design method of flexural capacity of RC beams strengthen by ultra-high-performance concrete

Due to the increase in traffic volume, load level, and service life of existing bridges, the bending bearing capacity of reinforced concrete beams (hereinafter referred to as RC beams) has decreased, leading to safety issues. In order to solve the problem of insufficient flexural bearing capacity of RC beams, this article adopts the method of ultra-high performance concrete (UHPC) flexural strengthening RC beams, establishes a finite element model of UHPC-RC reinforcement system, and conducts stress analysis with reinforcement thickness, reinforcement range, reinforcement form, and reinforcement height as parameters to determine the optimal scheme of the reinforcement system. Based on the calculation results, a theoretical formula for the maximum principal stress and maximum deflection of the reinforcement system is proposed. To verify the feasibility of the plan, a reinforcement design was carried out on an existing beam, and it was found that the bending bearing capacity of the RC beam increased by 21%; the high tensile strength of UHPC and the addition of steel fibers have a good limiting effect on cracks; The steel plate of the reinforcement system can be used as a template, reducing construction costs and having good economy.

Dynamic response characteristics and instability mechanism of layered surrounding rock tunnels affected by geostress under dynamic and static loads

Ensuring the safe excavation of layered surrounding rock tunnels requires a comprehension of the dynamic response characteristics and instability mechanism of the rock under dynamic and static loads. The impact of variations in geostress on tunnel stability is a concern that cannot be disregarded as long-distance tunnel construction continues to grow. This paper provides a detailed description of the maximum principal stress dynamic response and deformation characteristics of the tunnel's layered surrounding rock with the change of geostress under dynamic and static loads using model tests and numerical simulation methods. The effects of different loads, different geostress, different locations, and different failure modes on the maximum principal stress and displacement of the tunnel's layered surrounding rock are comparatively analyzed. A prediction model of the maximum principal stress and maximum displacement of the layered surrounding rock affected by geostress under the dynamic load is proposed by dimensional analysis. At last, based on the prediction model, the critical lateral pressure coefficient was obtained to be 0.74 and the maximum displacement of 12.98 mm appears at the left spandrel when the tunnel depth reaches the maximum of 963 m.

Land use and land cover mapping using Landsat-8 and Sentinel-2 data in Al Qunfudhah coast, western Saudi Arabia: A comparative study

Al Qunfudhah Governorate has assumed a tourist status in the strip of Saudi coastal cities on the Red Sea coast. Agriculture, food industries, and engineering industries are among the most important economic activities in the city. As a result, Land use and land cover (LULC) detection is essential for several reasons: urban planning, sustainability, resource management and environmental preservation. This research aims to identify the LULC of the Al Qunfudhah area in western Saudi Arabia by comparing Landsat-8 and Sentinel-2 data outputs and evaluating their accuracy results. Various methods are used to process satellite image data to enhance the contrast between surface features. Some of these techniques are true colour composite (TCC) images, enhanced true colour composite (ETCC) images, false colour composite (FCC) images, principal component analysis (PCA), band ratios and Maximum Likelihood Algorithm (MLA) Supervised Classification. By utilising band combination methods, PCA methods, and band ratio methods, we were able to map a variety of features, including vegetation cover, mangroves, Sabkha and non-Sabkha deposits, wadi basins, shallow and deep shelf areas, islands, sand and mud sediments, rocky reefs and urban areas. As part of the study, ArcGIS 10.8's supervised classification tool was employed to categorise the study region's features and calculate the percentage of each class. In both Landat-8 and Sentinel-2 classification images, the same classes were identified (i.e. sand and mud sediments, sabkhas, wadi basins, aeolian sand and loess sediments, islands, urban areas, vegetation, and mangroves). The accuracy of the classification results was determined using a reliable statistical approach. The accuracy assessments of Landsat-8 and Sentinel-2 revealed accuracy rates of 87% and 89.1% respectively, along with kappa coefficients of 84.9% and 87.3%. For the investigated area, the Landsat-8 and Sentinel-2 satellites were effective in producing LULC maps.

A Noninvasive Clinical Method to Measure in Vivo Mechanical Strains of the Lamina Cribrosa by OCT

To measure mechanical strain of the lamina cribrosa (LC) after intraocular pressure (IOP) change produced 1 week after a change in glaucoma medication. Cohort study. Adult glaucoma patients (23 eyes, 15 patients) prescribed a change in IOP-lowering medication. Noninvasive OCT imaging of the eye. Deformation calculated by digital volume correlation of OCT scans of the LC before and after IOP lowering by medication. Among 23 eyes, 17 eyes of 12 persons had IOP lowering ≥ 3 mmHg (reduced IOP group) with tensile anterior-posterior Ezz strain= 1.0% ± 1.1% (P= 0.003) and compressive radial strain (Err)=-0.3% ± 0.5% (P= 0.012; random effects models accounting inclusion of both eyes in some persons). Maximum in-plane principal (tensile) strain and maximum shear strain in the reduced-IOP group were as follows: Emax= 1.7% ± 1.0% and Γmax= 1.4% ± 0.7%, respectively (both P < 0.0001 vs. zero). Reduced-IOP group strains Emax and Γmax were significantly larger with greater % IOP decrease (P < 0.0001 and P < 0.0001, respectively). The compliances of the Ezz, Emax, and Γmax strain responses, defined as strain normalized by the IOP decrease, were larger with more abnormal perimetric mean deviation or visual field index values (all P ≤ 0.02). Strains were unrelated to age (all P ≥ 0.088). In reduced-IOP eyes, mean LC anterior border posterior movement was only 2.05 μm posteriorly (P= 0.052) and not related to % IOP change (P= 0.94, random effects models). Only Err was significantly related to anterior lamina depth change, becoming more negative with greater posterior LC border change (P= 0.015). Lamina cribrosa mechanical strains can be effectively measured by changes in eye drop medication using OCT and are related to degree of visual function loss in glaucoma. Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

AI-based denoising of head impact kinematics measurements with convolutional neural network for traumatic brain injury prediction.

Wearable devices are developed to measure head impact kinematics but are intrinsically noisy because of the imperfect interface with human bodies. This study aimed to improve the head impact kinematics measurements obtained from instrumented mouthguards using deep learning to enhance traumatic brain injury (TBI) risk monitoring. We developed one-dimensional convolutional neural network (1D-CNN) models to denoise mouthguard kinematics measurements for tri-axial linear acceleration and tri-axial angular velocity from 163 laboratory dummy head impacts. The performance of the denoising models was evaluated on three levels: kinematics, brain injury criteria, and tissue-level strain and strain rate. Additionally, we performed a blind test on an on-field dataset of 118 college football impacts and a test on 413 post-mortem human subject (PMHS) impacts. On the dummy head impacts, the denoised kinematics showed better correlation with reference kinematics, with relative reductions of 36% for pointwise root mean squared error and 56% for peak absolute error. Absolute errors in six brain injury criteria were reduced by a mean of 82%. For maximum principal strain and maximum principal strain rate, the mean error reduction was 35% and 69%, respectively. On the PMHS impacts, similar denoising effects were observed and the peak kinematics after denoising were more accurate (relative error reduction for 10% noisiest impacts was 75.6%). The 1D-CNN denoising models effectively reduced errors in mouthguard-derived kinematics measurements on dummy and PMHS impacts. This study provides a novel approach for denoising head kinematics measurements in dummy and PMHS impacts, which can be further validated on more real-human kinematics data before real-world applications.

UCLA Loneliness Scale in Nepal

The intention of this examination was to present innovative empirical evidence regarding the adaptation of the UCLA Loneliness Scale to Nepal and investigate the validity and reliability of the scale for Nepalese young elderly. The participants in this study were 513 young senior citizens aged in the age range 60 and 74. Among the participants, 243 (47.4%) were male, 270 (52.6%) were female and the mean age was found to be 65.86 (SD = 4.203). Principal Component Analysis (PCA) and Maximum Likelihood Analysis were used to evaluate the UCLA loneliness scale. The factor analysis resulted in one factor, where factor loadings of the items varied between 0.561 and 0.784 measuring in SPSS 20. The LISREL 8.8 program showed the factor loadings through ordinal analysis in the range of 0.695 and 0.917, and accordingly calculated Average Variance Explained (AVE) was 0.72. The computation of Cronbach alpha level was 0.945 and composite reliability was 0.98 in the examination of internal consistency of the variables. Findings suggested that the UCLA loneliness scale was found appropriate for use among Nepalese young senior citizens.

Application of Principal Component Analysis and Maximum Likelihood Estimation Method to Identify the Determinant Factors Intention to Use of Paylater in E-Commerce

This research aims to analyze which factors are most determining in influencing interest in using pay-later. This type of research is multivariate analytical research using a quantitative approach. All pay-later service customers who engage in e-commerce make up the study's population. Purposive sampling and non-probability sampling were employed in the sample-taking process based on this study. There are one hundred samples. Researchers have made observations to gather data. The author intends to employ principal component analysis and maximum likelihood estimation techniques for data analysis. Following the completion of the study, the following findings were made. The principal component analysis method's RMSE value is 0.02. The maximum likelihood estimates method's root mean square error is 0.015. Therefore, it can be said that the principal component analysis approach is appropriate for usage because it can explain factor formation due to its strong factor loading value and low RMSE value. The influence of advantages is the most important element determining interest in pay-later utilizing the principal component analysis method since it has the highest loading factor value in decision-making.

Assessment of biomechanical behavior of immature non-vital incisors with various treatment modalities by means of three-dimensional quasi–static finite element analysis

The objectives of this study were to evaluate the stress distribution and risk of fracture of a non-vital immature maxillary central incisor subjected to various clinical procedures using finite element analysis (FEA). A three-dimensional model of an immature central incisor was developed, from which six main models were designed: untreated immature tooth (C), standard apical plug (AP), resin composite (RC), glass-fibre post (GFP), regeneration procedure (RET), and regeneration with induced root maturation (RRM). Mineral trioxide aggregate (MTA) or Biodentine® were used as an apical or coronal plug. All models simulated masticatory forces in a quasi–static approach with an oblique force of 240 Newton at a 120° to the longitudinal tooth axis. The maximum principal stress, maximum shear stress, risk of fracture, and the strengthening percentage were evaluated. The mean maximum principal stress values were highest in model C [90.3 MPa (SD = 4.4)] and lowest in the GFP models treated with either MTA and Biodentine®; 64.1 (SD = 1.7) and 64.0 (SD = 1.6) MPa, respectively. Regarding the shear stress values, the dentine tooth structure in model C [14.4 MPa (SD = 0.8)] and GFP models [15.4 MPa (SD = 1.1)] reported significantly higher maximum shear stress values compared to other tested models (p < 0.001), while no significant differences were reported between the other models (p > 0.05). No significant differences between MTA and Biodentine® regarding maximum principal stress and maximum shear stress values for each tested model (p > 0.05). A maximum strain value of 4.07E−03 and maximum displacement magnitude of 0.128 mm was recorded in model C. In terms of strengthening percentage, the GFP models were associated with the highest increase (22%). The use of a GFP improved the biomechanical performance and resulted in a lower risk of fracture of a non-vital immature maxillary central incisor in a FEA model.

Ductile fracture behavior of in situ TiB2 particle reinforced 7075 aluminum matrix composite in various stress states

The fracture behavior of an in situ TiB2 particle reinforced 7075 aluminum matrix composite in various stress states was investigated by mechanical tests, microscopic characterization, and numerical simulations. Four sets of tensile specimens, one group of shear specimens, and one group of compression specimens were designed, and mechanical experiments were conducted on these six groups of specimens. The strain distributions of the six groups of specimens during deformation were investigated by in situ strain testing and finite element simulation. The fracture morphology of the specimens was characterized to analyze the damage mechanism in different stress states. It was found that the fracture mechanism of the material is mainly interfacial debonding and particle fracture, manifested as tensile fracture under high stress triaxiality and shear fracture under low stress triaxiality. For the tensile fracture, the nucleated voids grew with the maximum principal stress; for the shear fracture, they showed significant shape change with the maximum shear stress but little volume change. Based on the fracture mechanisms uncovered by the experiments, a modified ductile fracture criterion, considering the influence of both the maximum principal stress and maximum shear stress, was developed for the composite. Comparison with the modified Mohr–Coulomb, Lou–Yoon–Huh, Hu, and Mu models shows that the proposed model can predict the ductile fracture behavior of the aluminum matrix composites more accurately.

Enhanced microwave metrology using an optical grating in Rydberg atoms.

An enhanced measurement of the microwave (MW) electric (E) field is proposed using an optical grating in Rydberg atoms. Electromagnetically induced transparency (EIT) of Rydberg atoms appears driven by a probe field and a control field. The EIT transmission spectrum is modulated by an optical grating. When a MW field drives the Rydberg transition, the central principal maximum of the grating spectrum splits. It is interesting to find that the magnitude of the sharp grating spectrum changes linearly with the MW E-field strength, which can be used to measure the MW E-field. The simulation result shows that the minimum detectable E-field strength is nearly 1/8 of that without gratings, and its measurement accuracy could be enhanced by about 60 times. Other discussion of MW metrology based on a grating spectrum is also presented.

Effects of different custom-made mouthguard palatal extensions on the stress-state of dentoalveolar structures: a 3D-FEA.

The present study aimed to simulate the influence of palatal extensions for custom-made mouthguards (MGs) on protecting dentoalveolar structures and to provide a theoretical basis for designing a comfortable MG. Based on finite element analysis (3D-FEA), five groups of maxillary dentoalveolar models of wearing MGs were established: no MG on palatal side (NP), on palatal gingival margin (G0), 2 mm from the palatal gingival margin (G2), 4 mm from the palatal gingival margin (G4), 6 mm from the palatal gingival margin (G6), and 8 mm from the palatal gingival margin (G8). A cuboid was created to simulate the solid ground impacted in falls, a gradually increasing force was applied from 0 to 500 N on the vertical ground, and the distribution and peak values of the Critical modified von-Mises stress, maximum principal stress, and displacement of dentoalveolar models were calculated. Stress distribution range, stress, and deformation peak value of dentoalveolar models increased as the impact strength increased, at 500 N. Maximum critical modified von-Mises stress, peak maximum principal stress and maximum displacement of dentoalveolar models G4, G3, G2, G1, G0, and NP were 154.5 MPa, 154.5 MPa, 154.4 MPa, 154.7 MPa, 154.4 MPa, and 154.7 MPa; 191.65 MPa, 192.11 MPa, 191.62 MPa, 191.81 MPa, 191.56 MPa, and 191.62 MPa; and 88.78 μm, 88.57 μm, 88.19 μm, 88.67 μm, 88.43 μm, and 89.04 μ, respectively. However, the position of the MG palatal edge had little effect on stress distribution, stress, and deformation peak values of the dentoalveolar models. Different extension ranges of the MG palatal edge have little effect on the protective effects of MGs on maxillary teeth and maxilla. An MG with palatal extension on the gingival margin is more appropriate than other models and may help dentists to design a suitable MG and increase its usage. MGs with palatal extensions on the gingival margin may provide a more comfortable wearing experience for individuals involved in sports and encourage increased MG usage.

Establishment of a Finite Element Model of Normal Nasal Bone and Analysis of Its Biomechanical Characteristics.

Nasal bone is a long, paired series of small bones, which is narrow at the top and broad at the bottom, that forms the base of the nasal dorsum. Together with the nasal part of the frontal bone, the frontal process of the maxilla and the middle plate of the ethmoid bone constitute the bone scaffold of the external nose. In this paper, the DICOM image data file was imported into the Mimics software for 3D reconstruction. At the same time, the Geomagic software was used for relevant image processing, and the finite element software ANSYS was used to establish a finite element model to analyze the stress characteristics of the nasomaxillary complex. Results. The maximum principal stress and maximum strain force at the lower segment of nasal bone and the junction of nasal bone and maxilla were relatively large. When the same external force acts on the lower segment of the nasal bone and the angle is 0° (sagittal force), the maximum principal stress and maximum strain force are the smallest. When the angle continues to increase, the maximum principal stress and maximum strain force continue to increase.

Translation and psychometric testing of the sense of competence in Dementia Care Staff Scale in Chinese amongst dementia care staff in nursing homes of China

BackgroundAlthough China has the largest population of persons with dementia, there is no validated tool available to accurately assess formal caregivers’ competence in dementia care in long-term care settings. Appropriately assessing nursing staff’s level of competence in dementia care is the first step to develop precision training interventions to improve the quality of dementia care. The Sense of Competence in Dementia Care Staff scale (SCIDS) is a user-friendly tool with satisfactory reliability and validity. We adapted SCIDS into a Chinese version (SCIDS-C) and validated its uses in China’s socio-cultural context to assess nursing staff’s capability and competence in dementia care at nursing homes.AimsWe aimed to adapt and psychometrically test the tool among frontline nursing staff in long-term care settings in China.MethodsThe research employed a correlational design with repeated measures. In translation section, we adapted and tailored the original scale in the cultural and social context in China’s nursing homes. The scale’s adaptation consists of translating adaptation and semantic equivalence. In psychometric testing phase, we tested the validity and reliability of the scale with 174 nursing staff conveniently from six nursing homes. Construct validity was tested using exploratory factor analysis (EFA), including principal component analysis and maximum variance rotation method. Reliability was tested using Cronbach’s alpha value and intraclass correlation coefficient (ICC).ResultsThe SCIDS-C has 17 items, which belong to the two sub-scales, the Relationship-Centered Care(RCC) and Professional Care(PC). The Cronbach’s alpha value was 0.88, showing a good internal consistency. The full scale’s value of ICC was 0.94 which indicated good reliability. Exploratory factor analysis(EFA) extracted 2 common factors in each sub-scale, cumulative variance contribution rate was 56.71% and 53.92%, respectively. The named four factors are the same as the Sense of Competence in Dementia Care Staff (SCIDS) scale in English, including Building Relationships, Sustaining Personhood, Professionalism and Care Challenges.ConclusionThe SCIDS-C has shown good reliability and validity. It can be used as an appropriate tool to evaluate the competence of nursing care staff to provide dementia care for residents in nursing homes.

Stress distribution and displacement in the maxillofacial complex during intrusion and distalization of the maxillary arch using miniplates versus mini-implants: a 3-dimensional finite element study

ObjectivesTo three-dimensionally analyse the stress distribution and displacement pattern in the maxillofacial complex following intrusion and distalization of the maxillary arch using finite element analysis in skeletal class II malocclusion with prognathic maxilla and vertical maxillary excess using miniplates and mini-implants.Materials and methodsFinite Element models of a skull, Y-shaped stainless steel miniplate, mini-implant and a posted arch were generated. Three force levels (1) 200 g (2) 300 g and (3) 500 g per side were applied to the assembly. The models were pre-processed and the analysis was performed using ANSYS version 18.1 software. Alterations in von mises stress, principal maximum stress, principal minimum stress and compressive stress were analysed around the sutures and surface landmarks.ResultsWith miniplates, there was a maximum stress concentration at the zygomatic buttress with even stress distribution at the fronto-maxillary, zygomatico-temporal, zygomatico-frontal and pterygomaxillary sutures along with anatomical landmarks such as frontal process of maxilla, ANS, Point A, prosthion and maxillary process of zygoma. First molars experienced greater distalization effects with buccal flaring when miniplates were used. With mini-implants, canine and premolars also exhibited greater distalization effects. In the root apices, lateral incisors showed increased lingual root movement with mini-implants.ConclusionMiniplates provide a greater distalizing effect while mini-implants produce increased intrusive effect. The distalizing effect is greater when 500 g of force is applied using miniplates with significantly even stress distribution and displacement pattern.

Fishing activity in the Atlantic Moroccan Ocean: Mathematical modeling and optimal control

As it spans the Mediterranean sea and the Atlantic Ocean on the north and west respectively, Morocco is characterized by its marine sources’ diversity. Fishing Activity is considered to be the backbone of the country’s economy. the process of structuring the exploited population, and the marine environment are two major fields that the kingdom must understand to implement management measures to sustain the equilibrium of national fisheries and marine sources. Here, we have built a discrete-time model to describe the dynamic of fishing of two small pelagic species on the Atlantic Coast. The equilibrium between marine population and fishing effort, and maximizing profit are what the control parameter proposed have to achieve. We use a discrete version of Pontryagin’s principal maximum to calculate the optimal system. The numerical simulation is carried out using Matlab.

PATELLAR FRACTURE IN ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION: IN VITRO ANALYSIS.

To determine, by biomechanical analysis, safe patellar cut limits in anterior cruciate ligament (ACL) reconstruction that minimize fracture risks. From three-dimensional reconstruction, triangular cuts were made in the patella, with a depth of 6.5 mm and variable width and length (10 to 20 mm and 8 to 12 mm, respectively, both with an interval of 1 mm). The combinations of cuts constituted 55 models for tests, with five variations in width and 11 variations in length, tested with the finite element method (FEM). The mean of the localized principal maximum (traction force) values was 4.36 Pa (SD 0.87 ± 0.76) and the localized principal minimum (compression force) was -4.33 Pa (SD 1.05 ± 1.11). Comparing width and length to the tension force of the values of the main maximum, we found statistical significance from 11 mm for width and 13 mm for length. In ACL reconstruction, the removal of the patellar bone fragment is safe for fragments smaller than 11 mm in width and 13 mm in length, which corresponds to 24% of the width and 28% of the length of the patella used. Level of Evidence II, Comparative Prospective Study.

Factor analysis of beef gravel quality using Principal Component Analysis (PCA)

Factor analysis aims to reduce the amount of information from the original variable without losing important information. A factor is a collection of reduced variables. Several methods can be used in factor analysis, the most common of which are principal component analysis and maximum likelihood. The principal component analysis technique was used in this study. This technique was chosen because it better represents the purpose of the analysis than others. A case study of beef gravel is used to supplement the explanation of factor analysis using the Principal Component Analysis (PCA) technique. The goal of this study was to identify the most important factors influencing beef gravel quality to maintain product quality. The main factor is the volume of soaking water, and the second is the volume of soaking two dishes. These two factors have a cumulative variance proportion of 55%, indicating that they can influence the quality of the gravel. In contrast, the rest can be influenced by other factors not revealed in the research model.