Test Instrument Research Articles

The extended finite element method in endodontics: A scoping review and future directions for cyclic fatigue testing of nickel-titanium instruments.

The present study reviews the current literature regarding the utilization of the extended finite element method (XFEM) in clinical and experimental endodontic studies and the suitability of XFEM in the assessment of cyclic fatigue in rotary endodontic nickel-titanium (NiTi) instruments. An electronic literature search was conducted using the appropriate search terms, and the titles and abstracts were screened for relevance. The search yielded 13 hits after duplicates were removed, and four studies met the inclusion criteria for review. No studies to date have utilized XFEM to study cyclic fatigue or crack propagation in rotary endodontic NiTi instruments. Challenges such as modelling material inputs and fatigue criteria could explain the lack of utilization of XFEM in the analysis of mechanical behavior in NiTi instruments. The review showed that XFEM was seldom employed in endodontic literature. Recent work suggests potential promise in using XFEM for modelling NiTi structures.

Guided inquiry with Moodle to improve students’ science process skills and conceptual understanding

This study aims to improve and describe science process skills (SPS) and conceptual understanding (CU) college students through guided inquiry learning with Moodle (GI-Moodle). This quasi-experimental study used a pretest-posttest non-equivalent control group design. College students taking general biology courses at Faculty of Applied Science and Engineering (FSTT), Universitas Pendidikan Mandalika (UNDIKMA) participated in this study. They were divided into three classes: the experiment, control 1, and control 2. Their SPS was measured using an essay test instrument containing 18 items, while the CU was examined using 50 items multiple choice test and 5 items essay test. The obtained data were analyzed using the analysis of covariance (ANCOVA) test. The analysis results identified different average students’ SPS and CU before and after they attended the learning processes using GI-Moodle, guided inquiry with WhatsApp group (GI-WAG), and structured inquiry with WhatsApp group (SI-WAG). The experiment class attended learning using GI-Moodle presented a more significant increase of SPS and CU than the students attending the other two learning with GI-WAG and SI-WAG. Therefore, the GI with Moodle learning can be used to improve students’ SPS and CU during post COVID-19 pandemic. Besides, further studies are suggested to use a more number and broader participants and identify the influence of GI-Moodle on other variables.

Exploring morphometric transformations in temperature-sensitive NiTi instruments alongside real-time intracanal temperature dynamics.

This study was twofold: (i) it aimed to investigate the morphometric changes of three temperature-sensitive nickel-titanium (NiTi) instruments at different temperatures, and (ii) to conduct an invivo real-time analysis of intracanal temperature changes. Changes in the shape and length of XP-Endo Shaper, XP-Endo Finisher, and XP-Endo Finisher-R were evaluated in real time whilst heated in a temperature-controlled water bath from 22 to 45°C. Instruments were fixed to a laminated water-resistant 1 mm graph paper attached to a stone block. Instruments were imaged whilst subjected to increasing temperature using a digital camera attached to an operating microscope. From recorded videos, still frames were extracted at 10-s intervals and changes in the length and shape of each instrument were measured and changes were plotted against time. Moreover, the intracanal temperature of distal roots of lower molars was measured invivo for patients attending the clinic for non-surgical root canal treatments. The temperature was measured using a K-type thermocouple probe inserted into the mid-root level after irrigating the canal with a solution set at room temperature (22°C) or heated to 45°C. The intraoral and intracanal temperatures were recorded using a video camera for 180 s at 5-s intervals to plot the change in the intraoral and intracanal temperature, after both irrigation solution temperatures, with time. The shape transformation of XP-Endo Shaper began at 31.5 ± 2.0°C and reached its optimal transformation at 35.1 ± 1.0°C. For the Finisher and Finisher-R, shape transformations began at 29.2 ± 1.9 and 26.9 ± 2.2°C reaching the optimal transformation at 33.9 ± 1.4 and 32.7 ± 1.7°C, respectively. The average decreases in lengths of XP-Endo Shaper, Finisher, and Finisher-R after full transformation were 0.43 ± 0.23, 1.07 ± 0.22, and 1.15 ± 0.22 mm, respectively. The intracanal temperature reached 32.9 ± 0.8 and 33.2 ± 1.0°C after 3 min of application of irrigation solutions set at 22 or 45°C, respectively. The tested instruments exhibited diverse changes in their shapes and lengths at varying temperatures. Despite the temperature of the irrigation solution, the intracanal temperature consistently remained lower than the intracanal temperature once equilibrium was reached. This highlights the importance of considering the temperature of irrigation solution during invitro testing of endodontic instruments.

The Effect of Squat Training with Barbell and Resistance Band on Leg Power of Volleyball Athletes

The purpose of this study was to determine (1) the effect of squat training with barbell on increasing leg power of volleyball athletes, (2) the effect of squat training with resistance band on increasing leg power of volleyball athletes, (3) the difference in the effect of squat training with barbell and resistance band squats on increasing leg power of volleyball athletes. The type of research is experimental. The sample used is volleyball athletes totalling 20 athletes with an age range of 14-16 years. The leg power test instrument uses a vertical jump. Data analysis techniques using Paired Sample Test and Independent Samples Test. The results showed that (1) There is a significant effect of squat training with barbell on leg power of volleyball athletes (p 0.000 < 0.05), (2) There is a significant effect of squat with resistance band on leg power of volleyball athletes (p 0.000 < 0.05), (3) There is a significant difference in squat training with barbell and resistance band squats on increasing leg power of volleyball athletes. Squat training with resistance band is better than squats with barbell on increasing the leg power of volleyball athletes, with a difference of 1.30. The implication of the research results that to increase the leg power of volleyball athletes can be done by applying squat training with barbell and resistance band. This means that athletes are given exercises that are in accordance with their characteristics so that in the training process they feel happy and motivated to follow the training process, so that the training objectives will be maximised. Then another implication is that by encouraging coaches to apply suitable exercises can trigger athlete involvement in training.

Accuracy of the Bedside Examination in Patients with suspected Acute Unilateral Peripheral Vestibulopathy.

Acute unilateral peripheral vestibulopathy (AUPVP) is a frequent form of peripheral vestibular vertigo characterized by unilateral vestibular organ dysfunction. Diagnostic challenges in anamnesis and bedside examination can lead to potential misdiagnoses. This study investigated the sensitivity of bedside examinations in diagnosing AUPVP. This retrospective analysis examined 136 AUPVP inpatients at a level 3 university hospital between 2017 and 2019. Demographic data and bedside test results were collected. Instrumental otoneurological tests included caloric testing and video head impulse test (HIT). The sensitivity of each bedside parameter was computed based on the instrumental diagnostics, and statistical analyses were performed. The study included 76 men and 60 women, with a mean age of 59.2 years. Spontaneous nystagmus exhibited a sensitivity of 92%, whereas the absence of skew deviation was identified with a sensitivity of 98%. Abnormal bedside HIT showed a sensitivity of 87%. The combined HINTS (HIT, nystagmus, and test of skew) had a sensitivity of 83%. The Romberg test and Fukuda test demonstrated sensitivities of 26% and 48%, respectively. The sensitivity of bedside tests varied from 26% to 98%. This aligns with previous literature, highlighting the challenge of differentiating AUPVP from vestibular pseudoneuritis solely through bedside examination. Although the tests excel in excluding central causes, they are insufficient for diagnosing AUPVP with certainty. In addition, the bedside examination sensitivities vary widely, and early radiological imaging can be misleading. Therefore, this study underlines the necessity of prompt otoneurological testing for accurate exclusion of vestibular pseudoneuritis and thus improve patient outcomes.

Arthroscopic and open reconstruction of the posterolateral corner of the knee have equally good clinical results: first results of a prospective 12-month follow-up study.

Arthroscopic reconstruction techniques for higher-grade posterolateral corner (PLC) injuries (Fanelli Type B, PoLIS LI-B) have not yet been validated in clinical studies. The open reconstruction technique described by Arciero is well-established and showed good restoration of joint stability in previous studies. This study aimed to compare clinical outcomes of this established open surgery technique to a newly developed arthroscopic technique in a prospective randomized clinical trial. Between 2019 and 2021, this study focused on chronic high-grade PLC injuries (Fanelli Type B, PoLIS LI-B). Group A consisted of patients treated with conventional open surgery following Arciero's technique, while Group B included patients treated with Arciero's arthroscopic technique. All cases underwent additional PCL reconstruction. After a minimum 12-month follow-up, clinical scores and objective stability assessments were compared between the groups. In total, 26 (group A 12, group B 14) eligible patients with a mean follow-up of 14.9 ± 7.2 months were evaluated in the present study. Knee stability and patient-reported outcome scores (PROMS) were significantly improved when comparing pre- and post-operative values (p < 0.0001). No clinically relevant differences in PROMS (Lysholm: A 83.9 ± 11.4 vs. B 85.3 ± 13.8; IKDC: A 76.91 ± 12.6 vs. B 76.8 ± 15.7) were shown in both groups. Additionally, no statistically significant differences were detected between groups with respect to external rotation, range of motion and instrumental stability testing. Arthroscopic reconstruction showed significantly shorter operation time (p = 0.0109). There were no clinical failures or neurovascular complications of the surgical procedures. Both surgical techniques for isolated chronic PLC Fanelli Type B injuries significantly improved the knee stability, were equivalent with respect to PROMs and led to good clinical results. However, arthroscopic PLC reconstruction was associated with a shorter surgery time compared to open PLC reconstruction. Therefore, arthroscopic PLC reconstruction may be a viable option in the hands of an experienced surgeon. Prospective cohort study, II.

A Predictive Model for Wellbore Temperature in High-Sulfur Gas Wells Incorporating Sulfur Deposition

HSG (high-sulfur gas) reservoirs are prevalent globally, yet their exploitation is hindered by elevated levels of hydrogen sulfide. A decrease in temperature and pressure may result in the formation of sulfur deposits, thereby exerting a notable influence on gas production. Test instruments are susceptible to significant corrosion due to the presence of hydrogen sulfide, resulting in challenges in obtaining bottom hole temperature and pressure test data. Consequently, a WTD (wellbore temperature distribution) model incorporating sulfur precipitation was developed based on PPP (physical property parameter), heat transfer, and GSTP (gas–solid two-phase) flow models. The comparison of a 2.53% temperature error and a 4.80% pressure error with actual field test data indicates that the established model exhibits high accuracy. An analysis is conducted on the impact of various factors, such as production, sulfur layer thickness, reservoir temperature, and reservoir pressure, on the distribution of the wellbore temperature field and pressure field. Increased gas production leads to higher wellhead temperatures. The presence of sulfur deposits reduces the flow area and wellhead pressure. A 40% concentration of hydrogen sulfide results in a 2 MPa pressure drop compared to a 20% concentration. Decreased reservoir pressure and temperature facilitate the formation of sulfur deposits at the wellhead.

Optimal Instrument Selection Using Bayesian Model Averaging for Model Implied Instrumental Variable Two Stage Least Squares Estimators

Model-Implied Instrumental Variable Two-Stage Least Squares (MIIV-2SLS) is a limited information, equation-by-equation, noniterative estimator for latent variable models. Associated with this estimator are equation-specific tests of model misspecification. One issue with equation-specific tests is that they lack specificity, in that they indicate that some instruments are problematic without revealing which specific ones. Instruments that are poor predictors of their target variables (“weak instruments”) is a second potential problem. We propose a novel extension to detect instrument-specific tests of misspecification and weak instruments. We term this the Model-Implied Instrumental Variable Two-Stage Bayesian Model Averaging (MIIV-2SBMA) estimator. We evaluate the performance of MIIV-2SBMA against MIIV-2SLS in a simulation study and show that it has comparable performance in terms of parameter estimation. Additionally, our instrument-specific overidentification tests developed within the MIIV-2SBMA framework show increased power to detect specific problematic and weak instruments. Finally, we demonstrate MIIV-2SBMA using an empirical example.

Selected properties of X120Mn12 steel welded joints by means of the plasma-MAG hybrid method

The article describes properties of welds made of high wear resistance X120Mn12 steel obtained by the hybrid PTA-MAG (plasma transferred arc – metal active gas) method. The specimens were 8 mm thick rectangular (200 mm × 350 mm) sheets metal. The analyzed butt welds were made with the parameters selected according to the criterion of smallest cross-sectional area of welds and the narrowest HAZ (heat affected zone). The outcome of metallographic tests of weld, HAZ and parent material, hardness distribution and XRD (X-ray diffraction) patterns of selected areas are presented. The IIT (Instrumented Indentation Test) method was used to describe the distribution of mechanical properties shaped by thermal cycle annealing of the welding process. The investigation shows that the application of the PTA-MAG hybrid heat source for welding manganese steel enables the use of the filler material ER307 (AWS-A5.9). The hybrid PTA-MAG welding system has the relatively high potential to be an efficient alternative to welding standard processes for X120Mn12 steel due to the HAZ overheating limitation. The zone of high-risk weld cracking is the part of the HAZ close to the fusion area that has been reheated during weldment formation. Heat input about 0.6 kJ/mm is needed to provide full deep penetration butt weld without defects and with a vapor capillary of wide enough to cover the weld gap. The increase of hardness in the welded joint is smooth distributed and going up to 10% compared to the base material. The width of HAZ was &lt;1 mm. Intensive carbides precipitation in HAZ has been avoided successfully.

Experiences of experts in intelligence measurement of South African school learners

This qualitative research study emerged from the essential need for reliable and valid intelligence test instruments for South African school learners, who are characterised as a diverse population with their variety in culture, ethnicity, and language, as well as having unequal socio-economic and educational backgrounds. The aim of this research study was to use a qualitative interpretive description research design to explore and describe the experiences of both experts in intelligence test development and/or adaptation as well as psychologists and psychometrists who have administered intelligence tests to South African school learners in various contexts. Twelve psychologists and/or psychometrists were interviewed, of which six were also experts in test development and/or adaptation, which yielded four themes after thematic analysis, namely, utilised intelligence measurements in the current South African school learner context are less relevant; the South African education system is a major issue specifically within lower socio-economic status (SES) contexts; it does not seem feasible to design or adapt suitable intelligence measures that are valid and reliable in the current South African school learner context; and key informants’ recommendations from their experiences.Contribution: This research study contributes to the understanding of the measurement of intelligence of South African school learners in diverse contexts. Findings of this research study can guide the strategic process to design an intelligence instrument suitable for a South African population of school learners, informing fair assessment practices for multiethnic equalisation.

Science Fun Learning for the Students Affected of Natural Disasters

Fun learning will attract students to classroom learning activities learning, especially for victims of natural disasters. Students who experience natural disasters fear doing various things at home and outside the home (school). This study aims to find out whether fun science learning carried out by planting plants can improve students' understanding of learning science. This quantitative descriptive research uses test instruments to measure students' knowledge of family medicinal plant material. The population in this study was elementary school students who were victims of the earthquake natural disaster earthquake in 2022, while the research sample was 15 elementary school students. This sampling is done randomly. The data obtained were analyzed descriptively to determine improved student understanding of learning science. The results of data analysis showed that science fun learning applied through outdoor learning activities by planting family medicinal plants can increase students' understanding related to science material. However, the improvement is categorized as low based on the N-gain score 0.2. The recommendation of this study is to improve student understanding of when fun science learning should be supplemented with other methods by referring to the local wisdom of participants. Thus, the feeling of trauma that saddens the survivors will be slightly forgotten with fun activities and education.

Assessment of residual prestress in existing concrete bridges: The Kalix bridge

The direct socio-economic consequences of the deterioration of aging infrastructure systems have triggered a continuous process of revising and updating current design standards and guidelines for critical network components. Specifically, long-term degradation processes demand the analysis and evaluation of vital structural assets such as prestressed concrete bridges. It is crucial to develop theoretically consistent, user-friendly, and non-destructive methodologies that engineering professionals can employ to prevent and mitigate potential catastrophic outcomes during the service life of these bridges. This study provides a thorough review of the available testing methods employed over the years for prestressed concrete bridges and introduces a comprehensive framework for evaluating existing methods for residual prestress force assessment. Through a multi-criteria selection process, the three most feasible tests were designed and carried out on an existing 66-year-old balanced cantilever box girder bridge exposed to freezing temperatures that affected the instrumentation plan and test execution. Finally, predictive models compliant with standard codes were calibrated based on the experimental results and the life cycle loss of prestress forces was evaluated to assess relevant bounding intervals. Findings reveal limited on-site testing and discrepancies between calculated residual forces and predictions by standard codes. The saw cut method showed a 18% difference from the initial applied prestress according to the prestress protocol, suggesting the use of a cover meter and concrete modulus evaluation for improved accuracy. The strand cutting method resulted in a 14% difference, emphasizing the need for stress redistribution assessment. The second-order deflection method showed a 6% difference, indicating a focus on enhanced boundary conditions and thorough sensitivity analysis for future investigations.

The Effect of Remuneration and Work Motivation on the Performance of Administrative Employees

This study aims to determine and analyze the effect of Remuneration and Work Motivation on the Performance of Administrative Employees at RSUP Prof. Dr. R. D. Kandou. This study used a quantitative approach. The population in this study was administrative employees at RSUP Prof. Dr. R. D. Kandou. The sampling technique uses a simple random sampling technique. Data collection techniques by distributing questionnaires, while secondary data through literature studies by reading various literature. Data analysis techniques use Research Instrument Test (validity and reliability test), t test, F test, r square test and multiple linear regression analysis with the help of SPSS software. The results of this study show that: (1) Remuneration has a positive and significant effect on performance; (2) Work Motivation has a positive and significant effect on Performance; (3) Remuneration and Work Motivation have a positive and significant effect on Performance. The performance of administrative employees at RSUP Prof. Dr. R. D. Kandou is influenced by remuneration of 41.4% and work motivation of 31.4%. It is partially concluded that the variable of Work Motivation most dominantly affects the Performance of Administrative Employees. Suggestions that can be conveyed to RSUP Prof. Dr. R. D. Kandou that it is necessary to continue to monitor and evaluate employee performance so that the services provided to the community are maximized. Moreover, motivation at work is one of the factors that can improve the performance of administrative employees at RSUP Prof. Dr. R. D. Kandou.

INTEREST IN INVESTING IN MUTUAL FUNDS USING FINTECH APPLICATIONS: DETERMINANTS AND IMPACT ON MUTUAL FUND PURCHASE DECISIONS

The aim of this research was to analyze interest in investing in mutual funds using an applicationfintech: determinants and their impact on mutual fund purchasing decisions as well as to test the influence of motivation and knowledge on interest in investing in mutual funds and their impact on mutual fund purchasing decisions as well as finding out the most dominant variables. The population in this study were respondents who used the applicationfintech mutual funds. Samples are determined by techniquePurposive Sampling, with 130 respondents. The data collection technique used was a questionnaire. The analysis techniques used in this research are instrument testing (validity test and reliability test), classical assumption test, descriptive statistical analysis, factor analysis, hypothesis testing and coefficient of determination using the SPSS programfor windows 23.0. The research results show that there is a simultaneous or partial influence of motivation and knowledge on interest in investing in mutual funds, there is a simultaneous or partial influence of motivation and knowledge on mutual fund purchasing decisions, and there is an influence of interest in investing in mutual funds on mutual fund purchasing decisions. Based on the partial test results, it can be seen that motivation has the greatest influence on interest in investing in mutual funds and knowledge has the greatest influence on mutual fund purchasing decisions.

Content Framework for Modern Vehicle Technology Integration into Motor Vehicle Mechanic Work Curriculum in Technical Colleges in Gombe State, Nigeria

The main purpose of this study was to develop a content framework for inclusion of Modern Vehicle Technology into Motor Vehicle Mechanics Work MVMW curriculum in Government Science and Technical Colleges (GSTC) in Gombe State in order to enhance knowledge, attitude and skills for self-employment in modern vehicle maintenance and repairs and employable skills among MVMW trade students in technical colleges. The study was guided by 4 research questions. The population consisted of all the 30 MVMW trade teachers in Gombe State. The study adopted developmental research which was aimed to improve the current MVMW trade curriculum. A structured questionnaire was developed by the researcher with four point rating scale. The questionnaire was validated by four (4) experts from different field of Automobile Technology and trial tested on MVMW trade teachers. Mean and standard deviation was used to answer the responses while factor analysis and Cronbach Alpha was used to determine the validity and reliability of the instrument. The findings revealed that MVT content has four (4) units: these include: Introduction to MVT, Safety Rules and Regulation on MVT, Instrument for MVT Engine Testing and Measurement, It was recommended that: National Board for Technical Education (NBTE) should integrate these elements into the MVMW trade curriculum. Curriculum planners should adopt these clusters in designing the MVMW trade curriculum among other.

Delirium detection in the emergency department: A diagnostic accuracy meta-analysis of history, physical examination, laboratory tests, and screening instruments.

Geriatric emergency department (ED) guidelines emphasize timely identification of delirium. This article updates previous diagnostic accuracy systematic reviews of history, physical examination, laboratory testing, and ED screening instruments for the diagnosis of delirium as well as test-treatment thresholds for ED delirium screening. We conducted a systematic review to quantify the diagnostic accuracy of approaches to identify delirium. Studies were included if they described adults aged 60 or older evaluated in the ED setting with an index test for delirium compared with an acceptable criterion standard for delirium. Data were extracted and studies were reviewed for risk of bias. When appropriate, we conducted a meta-analysis and estimated delirium screening thresholds. Full-text review was performed on 55 studies and 27 were included in the current analysis. No studies were identified exploring the accuracy of findings on history or laboratory analysis. While two studies reported clinicians accurately rule in delirium, clinician gestalt is inadequate to rule out delirium. We report meta-analysis on three studies that quantified the accuracy of the 4 A's Test (4AT) to rule in (pooled positive likelihood ratio [LR+] 7.5, 95% confidence interval [CI] 2.7-20.7) and rule out (pooled negative likelihood ratio [LR-] 0.18, 95% CI 0.09-0.34) delirium. We also conducted meta-analysis of two studies that quantified the accuracy of the Abbreviated Mental Test-4 (AMT-4) and found that the pooled LR+ (4.3, 95% CI 2.4-7.8) was lower than that observed for the 4AT, but the pooled LR- (0.22, 95% CI 0.05-1) was similar. Based on one study the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) is the superior instrument to rule in delirium. The calculated test threshold is 2% and the treatment threshold is 11%. The quantitative accuracy of history and physical examination to identify ED delirium is virtually unexplored. The 4AT has the largest quantity of ED-based research. Other screening instruments may more accurately rule in or rule out delirium. If the goal is to rule in delirium then the CAM-ICU or brief CAM or modified CAM for the ED are superior instruments, although the accuracy of these screening tools are based on single-center studies. To rule out delirium, the Delirium Triage Screen is superior based on one single-center study.

A Systematic Review of Physical Modelling Techniques, Developments and Applications in Slope Stability Analyses

AbstractAn extensive evaluation of published articles suggests a lack of research on a systematic literature review relating to physical modelling techniques, developments and application in slope stability studies. However, there is growing interest in using physical model tests in slope stability investigations. The present study systematically reviews the methodologies and applications of physical modelling in slope stability research. The Scopus database was used to identify relevant studies which employed physical model tests in slope stability investigations. A combination of fifteen keywords was used to identify relevant articles. A PRISMA-P method for conducting a systematic review was adopted. Articles were screened and analysed, and extracted data were re-organised using an Excel sheet. Data relating to research objectives, physical model test techniques, instrumentation, scaling laws, numerical modelling, results, and findings were extracted and analysed. The systematic review highlights gaps requiring further studies, particularly in slope reinforcements using vegetation and strength deterioration of reinforcements performance under repeated loading exposures. It is found that scholars have not fully addressed the influence of loss of water on pore water regimes and its impact on stability when vegetation is applied as reinforcements. It is also found that the development of slope materials for soil slopes in physical model tests relies on the artificial development of such materials with minimal consideration of their long-term behaviour. Although other options, such as bio-cementation and desiccation techniques, which simulate the natural environment of the slopes, are neglected in slope material development, the present study recommends that future studies consider such techniques.

A Full-Scale Tidal Blade Fatigue Test using the FastBlade Facility

Fatigue testing of tidal turbine blades requires the application of cyclic loads without the ability to match the natural frequency of the blade due to their high stiffness and the associated thermal issues of testing composite materials at those frequencies (i.e., 18–20 Hz). To solve this, loading the blades with an auxiliary system is necessary; in most cases, a conventional hydraulic system tends to be highly energy-demanding and inefficient. A regenerative digital displacement hydraulic pump system was employed in the FastBlade fatigue testing facility, which saved up to 75 % compared to a standard hydraulic system. A series of equivalent target loads were defined using Reynolds-Averaged Navier Stokes (RANS) simulations (based on on-site collected water velocity data) and utilised in FastBlade to demonstrate an efficient way to perform fatigue testing. During the test, a series of measurements were performed on the blade response and the Fastblade test structure itself, providing novel insights into the mechanical behaviour of a blade, and enabling improved testing practice for FastBlade. Without catastrophic failure, the blade withstood the principal tidal loading for 20 years (equivalent). This test data will enable FastBlade to identify improvements to the testing procedures, i.e., control strategies, load introduction, instrumentation layout, instrument calibration, and test design.

Wear Rate, Tribo-Corrosion, and Plastic Deformation Values of Co-Cr-Mo Alloy in Ringer Lactate Solution.

This study investigates the tribocorrosion performance of a cast Co-Cr-Mo alloy prepared using casting and electromagnetic stirring (EMS) at specific frequencies. The tribocorrosion behaviour of the alloy was evaluated when exposed to Ringer's lactate solution to optimize the EMS parameters and improve its properties. The research focuses on biomedical implant applications and explores how EMS affects alloy wear and corrosion resistance. As did the friction coefficient and wear volume, the wear rate of samples produced with EMS frequencies of 75 Hz and 150 Hz decreased. These improvements are attributed to the ability of EMS to refine grain size and homogenize the microstructure, thereby increasing the resistance to tribocorrosion. Techniques such as scanning electron microscopy (SEM) and profilometry were used for surface and wear analysis, while mechanical properties were evaluated through instrumented indentation tests. The findings confirm that EMS improves the alloy's durability and tribocorrosion resistance, making it highly suitable for demanding biomedical applications such as joint replacements. This highlights the importance of advanced manufacturing techniques in optimizing biomedical alloys for simulated body conditions.

A new nanometre resolution method for probing densification ratio at nanoindentation sites in glass: Unravelling discrepancies in the literature

The region of permanent densification beneath a Berkovich indentation imprint in silica glass is investigated using a novel chemical dissolution technique. The use of the similitude regime in sharp indentation testing allows one to record reliable data with a good spatial resolution that makes it possible to deal with low loads (typically below 10 mN) and, more importantly, crack-free imprints. The densified zone dissolves more quickly than the non densified regions. The analysis of the results, along the vertical axis, indicates that the densification zone is rather homogeneous with a steep transition to the non densified zone. The size of the densification zone, with respect to the initial free surface, is estimated to be around two times the maximum penetration depth of the instrumented indentation test. These findings are compared with those obtained by numerical simulations using different constitutive equations from the literature. A very good concordance between Raman spectroscopy and chemical probe results is found for imprints made with no or few cracking events during indentation testing.