Test Procedure Research Articles

Precise Tool to Target Positioning Widgets (TOTTA) in Spatial Environments: A Systematic Review.

TOTTA outlines the spatial position and rotation guidance of a real/virtual tool (TO) towards a real/virtual target (TA), which is a key task in Mixed reality applications. The task error can have critical consequences regarding safety, performance, and quality, such as surgical implantology or industrial maintenance scenarios. The TOTTA problem lacks a dedicated study and it is scattered in different domains with isolated designs. This work contributes to a systematic review of the TOTTA visual widgets, studying 70 unique designs from 24 papers. TOTTA is commonly guided by the visual overlap -an intuitive, pre-attentive "collimation" feedback- of simple shaped widgets: Box, 3D Axes, 3D Model, 2D Crosshair, Globe, Tetrahedron, Line, Plane. Our research discovers that TO and TA are often represented with the same shape. They are distinguished by topological elements (e.g. edges/vertices/faces), colors, transparency levels, and added. shapes, widget quantity, and size. Meanwhile some designs provide continuous "during manipulation feedback" relative to the distance between TO and TA by text, dynamic color, sonification, and amplified graphical visualization. Some approaches trigger discrete "TA reached feedback" such as color alteration, added sound, TA shape change, and added text. We found the lack of golden standards, including in testing procedures, as current ones are limited to partial sets with different and incomparable setups (different target configurations, avatar, background, etc.). We also found a bias in participants: right-handed, young male, non-color impaired.

Greener lightweight foam concrete using seaweed industrial by-product to replace natural sand with inorganic salt as a stabilizer

In recent years, the seaweed industry has expanded, resulting in higher volumes of seaweed industrial by-products (SWB). People commonly dispose SWB on land, which raises environmental concerns due to its hazardous chemical content. The use of waste materials as alternatives to natural sand has gained attention due to its potential to reduce environmental impact. Therefore, this study aimed to develop a greener lightweight foam concrete (LFC) by incorporating 0-30% SWB as a replacement for natural sand in fine aggregates and evaluate its performance. Furthermore, the study investigated the inclusion of inorganic salt concentrations ranging from 0 to 15% into the concrete mixture to improve performance. The production, sampling, and testing procedures followed the SNI 8640:2018 standards. Properties like density, water absorption, drying shrinkage, and compressive strength were analyzed for SWB percentage (0-30%), salt concentration (0-15%), foaming pressure (0.20, 0.39, and 0.59 MPa), and curing duration (7, 14, and 28 days). Viable specimens were further examined for microstructure, energy intensity, CO2 emission, and production cost. Specimen FS5 met standards with a density of 707.1 kg/m3, compressive strength of 2.12 MPa, water absorption of 25.45% (v/v), and drying shrinkage of 0.13%. The energy intensity, CO2 emission, and total cost of greener LFC were calculated to be 159.88 MJ/m3, 188.98 kg of CO2/m3, and IDR 682,130/m3, respectively. Ultimately, this work greatly contributes to the field of green manufacturing and environmental sustainability by successfully decreasing energy intensity, CO2 emissions, and environmental harm in LFC production processes.

Effects of variation in exercise training load on cognitive performances and neurotrophic biomarkers in patients with coronary artery disease.

This study compared the effects of linear (LP) and nonlinear (NLP) training periodization on cognitive functions, neurotrophic biomarkers [plasma brain-derived neurotrophic factor (BDNF), insulin-like growth factor-1 (IGF-1)], and cathepsin-B in patients with coronary artery disease (CAD). Forty-four patients with CAD reported to our laboratory on two occasions to undergo testing procedures before and after training sessions, and were then blindly randomized to NLP or LP for 36 training sessions. Visit 1 included blood samples and a maximal cardiopulmonary exercise testing to get maximal oxygen uptake (V̇o2peak). Visit 2 included cognitive functions assessment. Thirty-nine patients completed the study (LP: n = 20, NLP: n = 19), with no observed changes in cognitive performances after the training intervention in either group. IGF-1 concentration decreased in both groups (time-effect: P < 0.001), whereas BDNF concentration increased (time-effect: P < 0.05) without group interaction, and cathepsin-B did not change after the intervention. Associations were found between ΔV̇o2peak and ΔBDNF (R2 = 0.18, P = 0.04), and ΔIGF-1 and Δshort-term/working memory (R2 = 0.17, P = 0.01) in the pooled sample, with ΔIGF-1 and ΔBDNF accounting for 10% of the variance in Δshort-term/working memory. In the LP group, associations were found between ΔV̇o2peak and ΔBDNF (R2 = 0.45, P = 0.02), ΔBDNF and Δshort-term/working memory (R2 = 0.62, P = 0.004), ΔIGF-1 and Δshort-term/working memory (R2 = 0.31, P = 0.01), and ΔIGF-1 and Δexecutive function (R2 = 0.22, P = 0.04). This study indicates that linear and nonlinear training periodization led to an increase in BDNF, and a decrease in IGF-1, without change in cognitive function in individuals with stable CAD.NEW & NOTEWORTHY We used a novel and supervised iso-energetic training, integrating both moderate- and high-intensity aerobic exercises. Our findings indicate that greater variation in training load did not yield cognitive enhancements, although both protocols exhibited positive effects on brain-derived neurotrophic factor (BDNF) levels. Moreover, this study establishes a clear positive association between short-term and working memory and neurotrophic biomarkers. In addition, the independent predictive value of change in insulin-like growth factor-1 (IGF-1) on improvement in short-term and working memory highlight the close relationship between neurotrophic markers and cognition. Consequently, our results advocate for exercise training interventions targeting neurotrophic biomarkers to enhance cognitive function among individuals with coronary artery disease.

Real world economic evaluation of CT-FFR in patients with suspected coronary artery disease

Abstract Background Incorporation of CT-derived fractional flow reserve (CT-FFR) enhances the precision of Coronary CT Angiography (CCTA) to detect hemodynamically significant coronary artery disease (CAD). However, the financial consequences remain unclear. Purpose Our objective is to assess the economic implications of CT-FFR in the Dutch Healthcare system. Methods This retrospective, single-center cost effectiveness analysis includes patient data of a previously published study assessing the impact of routine CT-FFR availability on clinical management. We collected medical resource use for both diagnostic and therapeutic cardiovascular care with a follow-up duration of 1 year. Costs of CT-FFR analysis were set at €1000, its current price for Dutch hospitals. Median total costs at were compared using the Wilcoxon rank sum test, including a sensitivity analysis in which cost estimations (without registered maximum tariffs) were increased or decreased with 10%. Results A total of 360 patients, classified as having low to intermediate risk of CAD, were enrolled in the study – 224 in the CCTA group and 136 in the CT-FFR group. In addition to undergoing more (invasive) diagnostic testing and revascularization procedures over the studied period, patients in the CCTA-group had more outpatient clinic consultations (p&amp;lt;0.001), presented more frequently to the emergency department (p=0.035) and spend more nights in the hospital (p=0.11). Median costs were €3.347 (IQR €1.066 – €4.862) in the CCTA-group and €1.436 (IQR €1.362 - €3.943) in the CT-FFR group (p=0.091). Increasing cost estimation with 10% revealed a median of €3.431 in the CCTA-group versus €1.479 in the CT-FFR group (p=0.078), decreasing with 10% showed median costs of €3.263 in the CCTA-group and €1.392 in the CT-FFR group (p=0.118). In our sample, CT-FFR guided care would have been significantly cheaper than CCTA-guided care at or below a market price of €770. Conclusion Despite the significant reduction in additional diagnostic testing and hospital visits in the CT-FFR group, CT-FFR guided care was not cheaper than CCTA-guided care at its current market price of €1.000. Economic cost-effectiveness would have occurred from a price of €770 per analysis. The large difference between medians suggests that the lack of significance might partially be attributed to insufficient power in this relatively small sample size. Additionally, this study did not account for costs associated with loss of productivity and quality of life. However, less additional diagnostic testing, less revascularization procedures and less hospital consultations and admissions leads to reduction in hospital resource consumption and patient burden, which is an important advantage of CT-FFR as the number of referred patients increases yearly.

Efficiency of multivariate tests in trials in progressive supranuclear palsy

Measuring disease progression in clinical trials for testing novel treatments for multifaceted diseases as progressive supranuclear palsy (PSP), remains challenging. In this study we assess a range of statistical approaches to compare outcomes as measured by the items of the progressive supranuclear palsy rating scale (PSPRS). We consider several statistical approaches, including sum scores, a modified PSPRS rating scale that had been recommended by FDA in a pre-IND meeting, multivariate tests, and analysis approaches based on multiple comparisons of the individual items. In addition, we propose two novel approaches which measure disease status based on Item Response Theory models. We assess the performance of these tests under various scenarios in an extensive simulation study and illustrate their use with a re-analysis of the ABBV-8E12 clinical trial. Furthermore, we discuss the impact of the FDA-recommended scoring of item scores on the power of the statistical tests. We find that classical approaches as the PSPRS sum score demonstrate moderate to high power when treatment effects are consistent across the individual items. The tests based on Item Response Theory (IRT) models yield the highest power when the simulated data are generated from an IRT model. The multiple testing based approaches have a higher power in settings where the treatment effect is limited to certain domains or items. The study demonstrates that there is no one-size-fits-all testing procedure for evaluating treatment effects using PSPRS items; the optimal method varies based on the specific effect size patterns. The efficiency of the PSPRS sum score, while generally robust and straightforward to apply, varies depending on the specific patterns of effect sizes encountered and more powerful alternatives are available in specific settings. These findings can have important implications for the design of future clinical trials in PSP and similar multifaceted diseases.

Unified Platform for Automated Tests of Inverter-Based Resources with Harware-in-the-loop

Testing of inverter-based resources (IBRs) faces challenges in establishing standardized procedures across all product development stages. Most of the testing approaches use Hardware-in-the-Loop (HIL) during the early stages independently from the final product testing, which can lead to discrepant results. To solve these issues, this paper proposes a unified platform for automatically testing IBRs. It can be used during all product development stages, from pure simulation to Controller Hardware-in-the-Loop (CHIL) and finally on the complete commercial product, ensuring uniform test procedures with different test setups. A case study describing compliance tests of grid-connection codes of photovoltaic (PV) inverters are presented to demonstrate the proposed approach. Experimental tests were performed in accordance to Brazilian grid-connection codes in an ISO/IEC 17025 accredited laboratory. The results obtained with the proposed platform in CHIL and full-hardware showed high similarity with the ones obtained with the accredited laboratory, validating the proposed approach. In addition, the platform can be used to perform tests not specified in standards and to verify the performance of IBRs in operating conditions that are often difficult to be tested in laboratory. Ensuring consistent test procedures, the platform facilitates comparable results along all the testing stages, reducing the product development cycle.

Misoprostol as Oral Solution or Oral Tablet for Induction of Labour (MISOBEST): A Randomised Controlled Non-Inferiority Trial.

To assess if off-label oral solution of misoprostol compared with licensed oral tablet of misoprostol approved for induction of labour (IOL) is as efficient in resulting in vaginal delivery within 24 h, using a non-inferiority design. Prospective, randomised, non-inferiority, open-label, blinded endpoint trial. Two tertiary level hospitals, Stockholm, Sweden, January 2022 to May 2023. In all, 874 women, without previous caesarean section, with an unripe cervix and a singleton, cephalic foetus at 37 + 0 to 42 + 0 gestational weeks, with a normal cardiotocography, planned for IOL were included. Women were randomised 1:1 to intervention (25 μg oral solution of misoprostol) or control (25 μg oral tablet of misoprostol) two-hourly for a maximum of eight doses. Subsequent methods of induction followed clinical practice. The primary outcome was vaginal delivery within 24 h tested using non-inferiority testing procedures at a non-inferiority margin of 5 percentage points. Secondary efficacy outcomes were tested for superiority of either treatment. Analyses were by intention-to-treat. There were 207 (47.4%) vaginal deliveries within 24 h for women receiving oral solution and 192 (43.9%) vaginal deliveries within 24 h for women receiving oral tablet, establishing non-inferiority with an absolute risk difference of 3.4% (95% CI -3.2% to 10.0%). Women receiving oral solution required fewer doses to reach active labour than women receiving oral tablet (5.7 vs. 6.1, p = 0.007). There were no significant differences for other secondary or safety outcomes. Off-label oral solution of misoprostol was non-inferior to the licensed oral tablet regarding efficacy of IOL defined as vaginal delivery within 24 h. Clinicaltrials.gov identifier: NCT05424445.

Transient Analysis of Flow Unsteadiness And Machine Instabilities In a Centrifugal Compressor at Surge and Second Quadrant Operation

Abstract Instabilities in turbomachinery operation originate from intrinsic flow unsteadiness, sudden variations of operating conditions, and interactions with the surrounding system, affecting both system stability and machine reliability. The flow unsteadiness, presenting a characteristic behaviour, requires a deep understanding of the underlying flow fundamentals, a careful analysis using advanced experimental methods and a clear distinction on how the system might lead to instabilities. The identified approach addresses deep surge and second quadrant characterization. The analysis presented here benefits from the responsiveness and flexibility of the experimental test rig, fine tuning of the system layout, the instrumentation installation, and the transient tests procedure. The main focus area is the time-frequency analysis of flow and pressure signals at transients, thus providing a proper reconstruction of flow mechanisms and instability evolution. Valuable techniques include: short-time fast Fourier transform, wavelet analysis, and Wigner-Ville distribution; coherence between flow and pressure, to trace waves propagation, is considered too. These, presented outlining their strengths and weaknesses, are evaluated considering real time field applicability with regards to computational resources too. The experimental campaigns and data processing are presented, with a test matrix covering a wide range of parameters, including system layout and surge volume size, rotational speeds, flow rates ranging from nominal point to full second quadrant operation. These data are vital for system modeling validation for a full compressor-system digital twin. Results indicate the importance of ensuring reliable data acquisition and analysis, with adequate instrumentation range, accuracy, synchronization, responsiveness and positioning.

Theoretical framework for learning through structural plasticity

A growing body of research indicates that structural plasticity mechanisms are crucial for learning and memory consolidation. Starting from a simple phenomenological model, we exploit a mean-field approach to develop a theoretical framework of learning through this kind of plasticity, capable of taking into account several features of the connectivity and pattern of activity of biological neural networks, including probability distributions of neuron firing rates, selectivity of the responses of single neurons to multiple stimuli, probabilistic connection rules, and noisy stimuli. More importantly, it describes the effects of stabilization, pruning, and reorganization of synaptic connections. This framework is used to compute the values of some relevant quantities used to characterize the learning and memory capabilities of the neuronal network in training and testing procedures as the number of training patterns and other model parameters vary. The results are then compared with those obtained through simulations with firing-rate-based neuronal network models. Published by the American Physical Society 2024

Compact and Simple Antenna Inspection Testing Range for 5G Smartphones

Abstract Over-the-air (OTA) antenna performance evaluation in the millimeter-wave (mmWave) band often relies on Compact Antenna Test Range (CATR) systems, which require large reflectors and a substantial measurement range volume. Such setups are impractical for rapid testing in space-constrained environments such as antenna fault diagnosis in smartphone manufacturing facilities. This paper presents a novel design methodology for highly compact antenna inspection testing range utilizing offset parabolic reflectors specifically designed for 5G smartphones. The proposed design system employs three small offset parabolic reflectors configured to account for beam tilting caused by smartphone back covers, eliminating the need to physically reposition the smartphone during testing. By directing electromagnetic fields toward a fixed receiver antenna from multiple angles corresponding to different antenna module positions, the system streamlines the test procedure, significantly reducing measurement time and measurement range volume. The proposed antenna inspection testing range provides a cost-effective and efficient solution for 5G antenna fault diagnosis in manufacturing facilities, ensuring rapid and reliable inspection while minimizing space requirements on the production line.

Exploring Patient Empowerment in Major Depressive Disorder: Correlations of Trust, Active Role in Shared Decision-Making, and Symptomatology in a Sample of Italian Patients.

Background/Objectives: Empowerment in medicine and psychiatry involves patients gaining control over health-related decisions, improving treatment adherence, outcomes, and satisfaction. This concept is especially significant in psychiatric care due to the complex challenges of mental health conditions, including stigma and impairment of emotional and cognitive functioning. We aim to investigate the correlations between patient trust, decision-making involvement, symptom severity, and perceived empowerment among individuals with Major Depression. Methods: Patients with Major Depressive Disorder were recruited in the "Policlinico G. Rodolico" psychiatry outpatient clinic from November 2022 to June 2023. Inclusion criteria: ages 18-65, ability to consent, stable condition, psychiatric medication history, and recent consultation. Exclusion criteria: psychotic features, bipolar disorder, substance abuse, high suicide risk, and severe comorbidities. Measures included the User Scale for Measuring Empowerment in Mental Health Services (SESM), Trust in Oncologist Scale (TiOS), Clinical Decision-Making Style for Patients (CDMS-P), and Hamilton Depression Rating Scale (HAM-D). Analysis used Kendall's Tau correlation and Two-One-Sided Tests procedure. Results: Seventy-three patients completed the study. No relationship was found between decision-making involvement and perceived empowerment (τ = -0.0625; p = 0.448), or between trust in psychiatrists and empowerment (τ = 0.0747; p = 0.364). An inverse correlation existed between patient involvement in therapy management and trust (τ = -0.2505; p = 0.002). Depression severity inversely correlated with empowerment (τ = -0.2762; p = <.001), but not with trust or decision-making involvement. Conclusions: The lack of significant correlations suggests that decision-making involvement and trust alone may not suffice to enhance empowerment. Trust may encourage patient passivity, while skepticism might drive active involvement. Higher empowerment is associated with less depressive symptoms, highlighting its potential connection with patient outcomes.

Reflex Sympathetic Dystrophy (Complex Regional Pain Syndrome I): A Descriptive Case Study

Complex regional pain syndrome type I (CPRS I, formerly known as reflex sympathetic dystrophy) is a painful neuropathic disorder that develops after trauma affecting the limbs without overt nerve injury. The clinical features are spontaneous pain, hyperalgesia, impairment of motor function, swelling and autonomic abnormalities. Besides pain, autonomic (sympathetic) disturbances are characteristic clinical symptoms. These include regional abnormalities of cutaneous, vascular and sudomotor function. At present CPRS I is a pure clinical diagnosis and no objective test procedure exists to diagnose this entity with high sensitivity and specificity. The primary objective of physiotherapeutic modalities is goal-oriented function restoration, henceforth it’s been proven that this syndrome has poor prognosis. Keywords: Hyperalgesia, Autonomic abnormalities, Sympathetic disturbances, Sudomotor abnormalities, CPRS I.

Testing the thermal performance of water cooling towers

Abstract The essential service water system (ESWS) in nuclear power plants circulates the water that cools fan coolers, cooling water heat exchangers, and condensers and other components before dissipating the heat into the environment. Because this includes cooling the systems that remove decay heat from both the primary system and the spent fuel rod cooling ponds, the ESWS is a safety-critical system. In locations without a large body of water in which to dissipate the heat, water is recirculated via a cooling tower. Cooling towers fall into two main categories: Natural draft and Mechanical draft. Since, the mechanical draft cooling towers are much more widely used; the focus is on them in this work to measure its performance. Therefore; the present work addresses the thermal acceptance test for mechanical draft water cooling tower in order to determine its thermal capability in accordance with the cooling technology institute (CTI) code recommendations. Both the Characteristic Curve and the Performance Curve Methods are used. A detailed description of the test procedure according to the CTI ATC-105 test code is presented, and the test code is applied on the Egypt second research reactor (ETRR-2) cooling tower as a case study. All the instruments used in the reactor plant are calibrated prior the test and the measured data is collected at regular intervals according to the code recommendations. The test result shows a tower capability of about 105 % and so the tower is thermally accepted.

Mode I cohesive law of birch wood-biobased adhesive systems

ABSTRACT The development and assessment of bio-based wood adhesives face challenges due to the limitations of conventional test procedures, particularly in predicting adhesive performance in real-world applications. This study investigated the mode I cohesive law of two birch wood-biobased adhesive systems, comparing them with conventional fossil-fuel-based systems. The experimental approach, developed during the ‘90s at Lund University, involves direct measurement of the traction-separation relation and allows evaluation of post-peak behaviour and fracture mechanical property characterisation. SEM analysis confirmed fracture development within the bond line for all tests. The birch–fish-adhesive bonds demonstrated peak stress of approx. 4 MPa, with serrated fracture surfaces and favourable fracture properties (specific fracture energy approx. 370 Nm/m2, brittleness approx. 40 GPa/m). Birch wood bonded with lignin-based adhesive showed lower, yet reasonable, levels of peak stress (approx. 3 MPa) but less favourable fracture properties (specific fracture energy approx. 110 Nm/m2, brittleness approx. 90 GPa/m), suggesting room for further optimisation.

Mastery learning guided by AI is superior to directed self-regulated learning in flexible bronchoscopy training - an RCT.

Simulation-based training has proven effective for learning flexible bronchoscopy. However, no studies have tested the efficacy of training towards established proficiency criteria i.e., mastery learning (ML). We wish to test the effectiveness of ML compared to Directed Self-Regulated Learning (DSRL) on novice bronchoscopists' end-of-training performance. In a standardized simulated setting, novices without prior bronchoscopy experience trained using an artificial intelligence (AI) guidance system that automatically recognizes the bronchial segments. They were randomized into two groups: the ML group and the DSRL group. The ML group trained until they completed two procedures meeting the proficiency targets: 18 inspected segments, 18 structured progressions, &lt;120 seconds procedure time. The DSRL group trained until they no longer perceived any additional benefits from training. Both groups then did a finalizing test, without the AI-guidance enabled. 24 participants completed the study, with 12 in each group. Both groups had a high mean number of inspected segments (ML=17.2 segments, DSRL=17.3 segments, P=.85) and structured progressions (ML=15.5 progressions, DSRL=14.8 progressions, P=.58), but the ML group performed the test procedure significantly faster (ML=107 seconds, DSRL=180 seconds, P&lt;.001). The ML did not spend significantly longer time training (ML=114 minutes, DSRL=109 minutes, P=.84). ML is a very efficient training form allowing novice trainees to learn how to perform a thorough, systematic, and quick flexible bronchoscopy. ML does not require longer time spent training compared to DSRL, and we therefore recommend training of future bronchoscopists by this method.

The acceptability of implementation of group B Streptococcus testing: Perspectives from women and health professionals in the GBS3 trial: A qualitative study

ObjectiveTo determine the acceptability of different methods of routine testing for group B Streptococcus (GBS) colonisation to pregnant women and health care professionals (HCPs), and to examine barriers and facilitators to their implementation. DesignQualitative study, embedded in a cluster randomised trial SettingFour NHS maternity units participating in the GBS3 Trial: two conducting routine antenatal enriched culture medium (ECM) testing; and two using routine rapid intrapartum testing.Sample39 women and 25 HCPs purposively sampled to ensure representation of women with various birthing experiences and different professions.MethodsWomen were interviewed approximately 12 weeks postpartum by telephone or online video call, using a semi-structured topic guide. HCPs were interviewed during the testing period of the trial. Interviews were transcribed for thematic analysis and summarised using the framework method. ResultsFour categories of interest emerged: (1) views of routine testing; (2) acceptability of the testing procedure; (3) preferences on the types of test; (4) improving the testing procedure. Routine GBS testing was well received by both women and HCPs. Most participants found the procedure acceptable and were willing to receive the offer of testing in the future. Preferences for different testing methods varied, with participants emphasising the importance of evidence and informed choice. ConclusionsRoutine GBS testing is acceptable to most women and HCPs. Areas for consideration and the practicalities of implementing testing in maternity services are highlighted.

An Adaptable Method for Rapid Fatigue Limit Prediction of Composite Materials Based on Acoustic Emission Technology

ABSTRACTEncouraged by the emerging infrared thermography (IT)–based technique for determining fatigue limit of composite materials, this study introduces a novel approach for the quick fatigue limit determination based on acoustic emission (AE) technology. The AE‐based method expands fatigue testing capabilities beyond the IT‐based methods. Fatigue experiments were conducted for the composite laminates and composite sandwich panels subjected to stepwise increasing cyclic loads. For composite laminate specimens subjected to tension–tension and tension–compression fatigue loads, the fatigue limits obtained by the AE‐based method are in good correlation with those acquired from the IT‐based method as well as the conventional up‐and‐down test procedure. In the tests for out‐of‐plane shearing fatigue limits of composite sandwich panel specimens, where the IT‐based method did not work properly, the AE‐based method performed well and obtained the fatigue limit estimation, which is in line with that derived from the S–N curve data, thereby demonstrating its high adaptability.

Effect of chronic alcohol exposure and single-prolonged stress on conditioned fear behavior

The present study investigated the impact of chronic intermittent ethanol (CIE) exposure and single-prolonged stress (SPS) on the acquisition of fear memories in both male and female Wistar rats. Adult rats were first subjected to CIE by vapor inhalation followed by SPS. Following a subsequent 8-day incubation period, the rats underwent a Pavlovian fear conditioning procedure (tone-shock pairings) followed by cued-tone extinction training, and then testing of extinction recall memory and fear renewal memory. In control animals that had not been exposed to either CIE or SPS, female rats exhibited significantly lower levels of freezing compared to male rats during tone-shock pairings. This lower level of freezing in female rats during conditioning was associated with an increased speed of movement compared to males. Also compared to males, female rats exhibited lower levels of fear extinction, recall, and renewal. Exposure to CIE, SPS, or CIE+SPS had no effect on freezing during the cued-conditioning, extinction, or extinction recall phases of the testing procedure in either sex. In fear renewal, CIE exposure decreased freezing in male but not female rats, while SPS increased freezing in female but not male rats. CIE exposure significantly reduced freezing during the fear renewal phase. Taken together, these results provide further evidence that male and female rats adopt different avoidance strategies for threat responding. These results also revealed that prior exposure to CIE, SPS, or CIE+SPS had minimal effects on threat responding using conditioned freezing as an indicator of fear responsivity.

Preliminary Test Estimation for Parallel 2-Sampling in Autoregressive Model

The purpose of this paper is to discuss the problem of estimation and testing the equality of two autoregressive parameters of two first-order autoregressive processes AR(1), where for each process, the observations are made at different time points. The primary interest is to propose the testing procedures for the homogeneity of autocorrelation parameters ρ1 and ρ2. Furthermore, we are interested in estimating ρ1 under uncertain and weak prior information about the possible equality of ρ1 and ρ2, though we may not have full confidence in the tenacity of this information. A large sample test for the homogeneity of the parameters is developed. Pooled “P” (or restricted estimator) and preliminary test “PT” estimators are proposed, and their properties are investigated and compared with the unrestricted estimator “UE” of ρ1.

Design of the testing procedure for investigation of Eryx conicus dermal armour characteristics

The aim of this work is to develop an experimental method suitable for the mechanical testing of highly non-standard biological samples such as snake skin with osteoderms. The objective of the method is to determine, whether the osteoderms provide a protective function for the animal in its natural environment. For this purpose, a simulation of rodents biting the skin based on uni-axial compressive loading using a synthetic tooth as a penetrator was developed with an emphasis on integration with X-ray scanners to facilitate in-situ testing. To identify and characterise the structure of snake skin and to prove the protective function of osteoderms, all samples were subjected to high resolution X-ray computed tomography. The results of the experiments are presented in the form of stress-strain curves and a map of the tangent modulus.