bluuebunny/crossref_metadata_2025 huggingface dataset:
Event-triggered finite-time consensus control of leader–follower multi-agent systems with unknown velocities
Authors: Zhi Yuanyuan , Zhao Zhanshan , Qi Mingce
Published: March 2023

We proposed an event-triggered finite-time consensus (FTC) control scheme for second-order leader–follower nonlinear multi-agent systems (MASs) with unknowable velocities and external disturbances. Because of the immeasurable problem of system velocities, a terminal sliding mode observer (TSMO) which forces velocity errors to converge to zero in a finite time is introduced. Then, construct a distributed event-triggered control law by backstepping method, so that each follower can update the control law independently based on its state error threshold. It is demonstrated that the control scheme can achieve FTC stability and simultaneously ensure the global robustness of the system via the Lyapunov stability analysis. Meantime, the control scheme reduces frequent updates of the control law. Furthermore, there exists a positive lower bound for the inter event time sequence so that the Zeno phenomenon is rejected. In conclusion, the validity of the consensus control protocol is verified by the numerical simulations.
Observer-based event-triggered adaptive neural control for time-delay nonlinear systems with input saturation and external disturbances
Authors: Wu Peng , Liu Wenhui , Lu Yuan
Published: March 2023

In this article, the issue of adaptive event-triggered tracking control is investigated for time-delay nonlinear systems with input saturation and external disturbances. In the whole process of control design, the radial basis function neural networks are utilized to approximate uncertain nonlinearities. To estimate the unknown states, a neural network-based observer is constructed. Pade approximation method is adopted to eliminate the effect of input delay. A smooth non-affine function is introduced to replace input saturation, and an auxiliary variable is employed to obtain the actual control input. An event-triggered strategy is designed to reduce the utilization of communication and computation resources. Moreover, the command filtering technique is applied to handle the issue of “explosion of complexity” in the conventional backstepping method. The designed controller can assure that all the signals in the closed-loop system are semi-globally uniformly ultimately bounded. Therefore, the proposed event-triggered neural control scheme can not only save network resources, but also improve the robustness of the system by dealing with input constraints and external disturbances. Finally, two simulation examples are given to verify the availability and feasibility of the designed controller.
Lithofacies classification and itssignificance on oil and gas exploration of the Permain Fengcheng mixed shale in the Hashan area, northwestern Junggar Basin, China
Authors: Zhou Jian , Lin Chengyan , Liu Huimin , Zhang Guanlong , Zhang Kuihua , Yu Hongzhou , Wang Qianjun , Cai Qianru
Published: March 2023

The Fengcheng Formation in the Hashan area of the northwestern Junggar Basin is a complex fine-grained sedimentary rock deposited in a saline-alkaline lake basin and influenced by mechanical, volcanic, chemical, and biological processes. The Fengcheng Formation, influenced by synsedimentary volcanism, has a complex mineral composition, abundant organic matter, and frequent sedimentary structure. As a result, the commonly used lithofacies classification scheme based on rock composition and grain size is difficult to characterize accurately, hampering the evaluation of the Fengcheng Formation's hydrocarbon exploration potential. Therefore, the shale lithofacies classification scheme of Fengcheng Formation was proposed. This scheme classifies the Fengcheng Formation shales into four categories and eight sub-categories based on terrigenous clasts, carbonate minerals, and volcanic clasts, as well as organic matter content and sedimentary structure. Furthermore, this scheme considers the organic and tuffaceous matter, which is essential for evaluating hydrocarbon generation properties, reservoir properties, and the brittleness of fine-grained sedimentary rocks.
Nasal Presentations of Rosai–Dorfman Disease: Clinical Manifestation and Treatment Outcomes
Authors: Xu Haoyuan , Zhang Huankang , Li Wanpeng , Zhang Chen , Wang Huan , Wang Dehui
Published: March 2023

Purpose

There has been a lack of evidence-based management strategies on the nasal presentations of Rosai–Dorfman disease (RDD). We aim to investigate the clinical manifestation, treatment, and outcomes in patients with nasal RDD.

Methods

We retrospectively reviewed available medical records of patients diagnosed with nasal RDD from 2014 to 2021 at our department.

Results

A total of 26 patients were included with a marked female preponderance (2.25:1). The most common symptom and affected sites were nasal congestion (31%) and nasal cavity (73%), respectively. The average times of biopsies was 1.5 times (range: 1–3). The histiocytes were positive about S100 and CD68 and negative for CD1a with common emperipolesis. The mean duration of follow-up was 34 months (range, 3–87). One patient with concomitant nasal small B-cell lymphoma achieved complete remission after chemoradiotherapy. Recommended treatments were endoscopic resection (92%) and oral corticosteroids (21%). Surgery was performed to remove the resectable lesion as completely as possible. Corticosteroids induced almost 100% overall remission. Of the relapses, two patients achieved an overall response and one remained in progressive stage after subsequent excision. Two patients only received dissection biopsy that responded to oral corticosteroid administration and combined therapies of lenalidomide and dexamethasone, respectively.

Conclusions

Diffuse lesions in nasal cavity and sinuses, and even widely affected nasal skull base, laryngopharynx, orbit, and cavernous sinus, should be considered the possibility of Rosai–Dorfman disease. Characteristic immunohistochemical staining is helpful for the diagnosis. Endoscopic surgical therapy remains the mainstream treatment for patients enduring an unbearable course. Oral corticosteroid administration serves as an adjuvant therapy for first-line treatments.
Hidden Structures: How Knowledge of New Practices Moves Among Educators in One Rural School District
Authors: Karnopp Jennifer R.
Published: March 2023

Background/Context:

Rural districts often struggle to provide organizational structures that support knowledge-building and sharing among educators, contributing to the challenge of change implementation in rural contexts. Although prior scholarship identifies social relationships centered on trust as important for fostering educator learning, we know little about how knowledge regarding a change initiative moves through a district lacking formal organizational learning supports and the role that informal relationships may play in fostering educator knowledge-building for organizational learning in an under-resourced rural context.

Purpose/Objective/Research Question/Focus of Study:

This article explores the network of knowledge related to a recent change initiative in a rural district striving to implement new instructional practices. Of particular interest is how knowledge is created and shared among educators and the role that organizational structures and informal relationships play in educators’ knowledge-building and sharing processes.

Research Design:

I present a conceptual model that brings together knowledge-creation and structuration theories. Using a sequential mixed methods design, I examine the information and advice interactions and knowledge-building experiences of educators in one rural school district. Analytical methods include social network analysis of survey data and thematic analysis of interview data.

Conclusions/Recommendations:

Findings suggest that informal relationships were consequential to organizational learning in this district with few formally designated learning supports, though friendship relationships were not consequential. Instead, knowledge-building interactions occurred when individual educators had a positive prior relationship; when mundane organizational structures, such as the master schedule and the assignment of informal or extracurricular roles, facilitated informal interactions; and when educators were motivated to engage in such interactions. This article makes three important contributions to our understandings of organizational learning in this under-resourced rural district context: (1) through mundane organizational structures, principals influence informal knowledge interactions; (2) educator agency is critical for change implementation; and (3) recursive educator interactions may constitute an informal organizational learning structure. This informal structure supporting organizational learning that was invisible to school leadership—fed by recursive informal interactions and supported by mundane organizational structures—represents a fertile area for future research.
Danmu video as the resemiotised: An attitudinal analysis of Home Visit
Authors: Jing Yi , Xu Qingxin
Published: March 2023

Danmu has been gaining increasing popularity in Chinese video-sharing platforms where users can project their comments directly onto the original video. Its popularity resonates with the general trend where user-generated content plays an increasingly important role. This article investigates possible meaning-making shifts produced by danmu from the perspective of resemiotisation. By deploying the Appraisal framework, particularly the attitude system, this study examines the attitudinal meanings expressed in a video and its danmu version. Comparisons between the two sets of attitudinal meanings reveal two patterns of meaning-making shifts. One is a shift in perspective, that is from whose perspective a certain scenario is presented. The other is a shift in the characterisation of one participant in the video. These findings raise our awareness of the possible manipulation of meaning afforded by danmu, which allows viewers to contribute directly to the meaning making of the danmu video. Danmu’s enablement of viewers’ co-production greatly extends the meaning and the meaning potential that could be afforded by the original video, which calls for a reconsideration of the purpose of video sharing, and the relationship between the original producer and viewers.
Strategy use in a spoken dialog system–delivered paired discussion task: A stimulated recall study
Authors: Gokturk Nazlinur , Chukharev-Hudilainen Evgeny
Published: March 2023

With recent technological advances, researchers have begun to explore the potential use of spoken dialog systems (SDSs) for L2 oral communication assessment. While several studies support the feasibility of building these systems for various types of oral tasks, research on the construct validity of SDS-delivered tasks is still limited. Thus, this study examines the cognitive processes engaged by an SDS-delivered paired discussion task, focusing on strategic competence, an essential component of L2 oral communication ability. Thirty adult test-takers completed a paired discussion task with an SDS acting as an interlocutor and provided stimulated recalls about their strategy use in the task. Three trained raters independently evaluated the test-takers’ oral task responses using a holistic rating scale devised for the task. Findings revealed the use of six categories of construct-relevant strategies during task performance. While no statistically significant differences were found in the use of these categories between high- and low-ability test-takers, marked differences were observed in the use of individual strategies within the categories between the test-takers at the two levels. These findings provide insight into how test-takers at different ability levels cognitively interact with SDS-delivered paired discussion tasks and offer implications for the design and validation of such tasks.
A brief overview of a mouse model of cerebral hypoperfusion by bilateral carotid artery stenosis
Authors: Ishikawa Hidehiro , Shindo Akihiro , Mizutani Akane , Tomimoto Hidekazu , Lo Eng H , Arai Ken
Published: March 2023

Vascular cognitive impairment (VCI) refers to all forms of cognitive disorder related to cerebrovascular diseases, including vascular mild cognitive impairment, post-stroke dementia, multi-infarct dementia, subcortical ischemic vascular dementia (SIVD), and mixed dementia. Among the causes of VCI, more attention has been paid to SIVD because the causative cerebral small vessel pathologies are frequently observed in elderly people and because the gradual progression of cognitive decline often mimics Alzheimer’s disease. In most cases, small vessel diseases are accompanied by cerebral hypoperfusion. In mice, prolonged cerebral hypoperfusion is induced by bilateral carotid artery stenosis (BCAS) with surgically implanted metal micro-coils. This cerebral hypoperfusion BCAS model was proposed as a SIVD mouse model in 2004, and the spreading use of this mouse SIVD model has provided novel data regarding cognitive dysfunction and histological/genetic changes by cerebral hypoperfusion. Oxidative stress, microvascular injury, excitotoxicity, blood-brain barrier dysfunction, and secondary inflammation may be the main mechanisms of brain damage due to prolonged cerebral hypoperfusion, and some potential therapeutic targets for SIVD have been proposed by using transgenic mice or clinically used drugs in BCAS studies. This review article overviews findings from the studies that used this hypoperfused-SIVD mouse model, which were published between 2004 and 2021.
Predicting brain temperature in humans using bioheat models: Progress and outlook
Authors: Sung Dongsuk , Rejimon Abinand , Allen Jason W , Fedorov Andrei G , Fleischer Candace C
Published: March 2023

Brain temperature, regulated by the balance between blood circulation and metabolic heat generation, is an important parameter related to neural activity, cerebral hemodynamics, and neuroinflammation. A key challenge for integrating brain temperature into clinical practice is the lack of reliable and non-invasive brain thermometry. The recognized importance of brain temperature and thermoregulation in both health and disease, combined with limited availability of experimental methods, has motivated the development of computational thermal models using bioheat equations to predict brain temperature. In this mini-review, we describe progress and the current state-of-the-art in brain thermal modeling in humans and discuss potential avenues for clinical applications.
Temperature dysregulation during therapeutic hypothermia predicts long-term outcome in neonates with HIE
Authors: Mietzsch Ulrike , Flibotte John J , Law Janessa B , Puia-Dumitrescu Mihai , Juul Sandra E , Wood Thomas R
Published: March 2023

Few reliable or easily obtainable biomarkers to predict long-term outcome in infants with hypoxic-ischemic encephalopathy (HIE) have been identified. We previously showed that mattress temperature (MT), as proxy for disturbed temperature regulation during therapeutic hypothermia (TH), predicts injury on early MRI and holds promise as physiologic biomarker. To determine whether MT in neonates treated with TH for moderate-severe HIE is associated with long-term outcome at 18–22 months, we performed a secondary analysis of the Optimizing Cooling trial using MT data from 167 infants treated at a core temperature of 33.5°C. Median MTs from four time-epochs (0–6 h, 6–24 h, 24–48 h, and 48–72 h of TH) were used to predict death or moderate-severe neurodevelopmental impairment (NDI), using epoch-specific derived and validated MT cutoffs. Median MT of infants who died or survived with NDI was consistently 1.5–3.0°C higher throughout TH. Infants requiring a median MT above the derived cut-offs had a significantly increased odds of death or NDI, most notably at 0–6 h (aOR 17.0, 95%CI 4.3–67.4). By contrast, infants who remained below cut-offs across all epochs had 100% NDI-free survival. MTs in neonates with moderate-severe HIE during TH are highly predictive of long-term outcome and can be used as physiologic biomarker.
Clinicopathological features and prognosis of primary pulmonary rhabdomyosarcoma in middle-aged and elderly patients: a case report and literature review
Authors: Xiaoxia Jin , Guihua Zheng , Jiatai Wang , Xinghua Zhu , Xudong Chen , Yingze Wei
Published: March 2023

To date, only 34 cases of primary pulmonary rhabdomyosarcoma (PPRMS) in the middle-aged and elderly population have been published. However, analyses of the clinicopathological characteristics and prognosis of PPRMS in this population have not been performed. A 75-year-old man visited our hospital because of abdominal pain and discomfort. His serum lactate dehydrogenase, neuron specific enolase, and progastrin-releasing peptide levels were elevated. Positron emission tomography–computed tomography revealed a lobulated mass of 7.6 × 5.5 cm2 in the lower lobe of the left lung with abnormally high fluoro-2-deoxy-d-glucose metabolism. Histologically, the tumor cells were small with little cytoplasm, deep nuclear staining, and heavily stained nuclear chromatin. Immunohistochemically, the tumor cells were positive for desmin, MyoD1 myogenin, synaptophysin, and CD56. Cytogenetic analysis for FOXO1A translocation was negative. Finally, the patient was diagnosed with PPRMS. He received combined chemotherapy with vincristine 1 mg, actinomycin 0.4 mg, cyclophosphamide 0.8 mg; however, only one course of chemotherapy was completed, and the patient died 2 months after diagnosis. PPRMS in middle-aged and elderly people is a highly malignant soft tissue tumor with significant clinicopathological characteristics.
Subacromial Balloon Spacer Implantation for Massive Irreparable Rotator Cuff Tears Is Associated With Restoration of the Acromiohumeral Interval and Glenohumeral Center of Pressure: A Systematic Review and Meta-Analysis of Controlled Laboratory Studies
Authors: Kunze Kyle N. , Moran Jay , Taylor Samuel A. , Fu Michael C. , Rodeo Scott A. , Warren Russell F. , Dines David M. , Gulotta Lawrence V. , Dines Joshua S.
Published: March 2023

Background:

Biodegradable subacromial balloon spacers (SBSs) have become increasingly used for the treatment of massive irreparable rotator cuff tears given their theorized clinical benefits; however, the relationship between biomechanical functions of the balloon spacer and clinical benefits remains unclear.

Purpose:

To perform a systematic review and meta-analysis of controlled laboratory studies investigating the use of SBSs for massive irreparable rotator cuff tears.

Study Design:

Systematic review and meta-analysis; Level of evidence, 4.

Methods:

PubMed, OVID/Medline, and Cochrane databases were queried in July 2022 for biomechanical data pertaining to SBS implantation in cadaveric models of irreparable rotator cuff tears. Random-effects meta-analysis of continuous outcomes using the DerSimonian-Laird method was performed to estimate pooled-treatment effect sizes between the irreparable rotator cuff tear state and the state in which an SBS was implanted. Data reported variably or in formats not amenable to analysis were presented descriptively.

Results:

Five studies involving 44 cadaveric specimens were included. At 0° of shoulder abduction, SBS implantation resulted in a mean inferior humeral head translation of 4.80 mm (95% CI, 3.20-6.40; P < .001) relative to the irreparable rotator cuff tear state. This decreased to 4.39 mm and 4.35 mm at 30° and 60° of abduction, respectively. At 0° of abduction, implantation of an SBS was associated with a 5.01-mm (95% CI, 3.56-6.46, P < .001) anterior translation of the glenohumeral center of contact pressure relative to the irreparable tear state. This translation changed to 5.11 mm and 5.49 mm at 30° and 60° of abduction. In 2 studies, SBS implantation restored the glenohumeral contact pressure to that of the intact state and significantly reduced subacromial pressure distribution over a rotator cuff repair state. In 1 study, a high balloon fill volume (40 mL) resulted in a significant 10.3 ± 1.4–mm more anterior humeral head position relative to the intact cuff state.

Conclusion:

SBS implantation in cadaveric models of irreparable rotator cuff tears results in significant improvements in humeral head position at 0°, 30°, and 60° of shoulder abduction. Balloon spacers may also improve glenohumeral and subacromial contact pressures, although insufficient evidence currently exists to corroborate these findings. High balloon fill volumes (40 mL) may confer supraphysiologic anteroinferior translation of the humeral head.
Labor Unbound? Assessing the Current Surge in Labor Activism
Authors: Vallas Steven Peter , Johnston Hannah
Published: March 2023

Where will the current surge of labor activism lead? To address this question we examine two distinctive currents of labor struggle—one rooted in “new economy” firms and a second in the nation's logistics sector—where post-pandemic conditions have confronted workers with important opportunities and challenges. If the workers’ movement is to make enduring gains, it will need to foster organizational alliances that stretch across distinct sectors of the economy, build support among consumers and the broader public, and challenge culture war rhetoric through appeal to workers’ shared needs.
Highway to the Danger Zone: Spatial Considerations of Catalytic Converter Theft
Authors: Reinhard Daniel , McDowell Molly
Published: March 2023

Limited research exists on catalytic converter theft despite it being a persistent issue for years. This study relies on police data for catalytic converter thefts ( n  =  414) in a medium-sized city for 18 months in 2021–2022. The study also uses vehicle registrations in the county, and Census data. Negative binomial regression models use Census Block Groups ( n  =  92) and consider neighborhood and environmental characteristics. The most likely vehicles to have catalytic converters stolen are the Honda Element, Toyota Prius, and Ford E-Series van. More than half of thefts occurred in parking garages and parking lots. Regression models find that the most consistent predictor of catalytic converter theft is adjacency to arterial roadways. Results suggest police departments should target efforts at parking garages and lots near highways, close to downtown, in areas that experience other kinds of crime. The situation changes when considering additional neighborhood characteristics, though highways are still a significant predictor.
Impact of additive manufacturing on reaction to fire
Authors: Nazé Thomas , Poutch Franck , Bonnet Fanny , Jimenez Maude , Bourbigot Serge
Published: March 2023

Additive manufacturing, including fused deposition modelling, is a growing technology opening up wide perspectives in material sciences. However, the ability to produce suitable fire-retarded materials via this process has never been studied extensively. This work focuses on understanding the relation between reaction to fire and numerous additive manufacturing parameters. The goal was to determine the impact of those parameters on standard fire tests such as flame propagation test (UL94V) and cone calorimetry. The results were compared with material samples formulated via usual processes. On one hand, flame propagation results are impacted by many additive manufacturing parameters, such as the design of the part and the material flow. On the other hand, cone calorimeter results are only influenced by parameters having an impact on the sample mass.
Helping Youth Navigate Privacy Protection: Developing and Testing the Children's Online Privacy Scale
Authors: Andrews J. Craig , Walker Kristen L. , Netemeyer Richard G. , Kees Jeremy
Published: March 2023

As children’s and teens’ internet use has reached record highs, the protection of their online privacy is a pressing issue for parents, consumer groups, social media firms, and federal, state, and international agencies. Even with strategies to help children protect their personal information, questions remain as to what children really know about the risks of interacting online. Thus far, much of the online privacy research has relied on subjective measures of adult beliefs and attitudes, which may not be predictive of children's online privacy behaviors. To address these issues, the authors develop and test a children's online privacy scale tapping different content domains of objective knowledge about online privacy for children and young teens (age 6–15 years). From this conceptualization, evidence is offered in two pretests and four studies supporting the scale's structure, reliability, and validity and its relationships with online privacy education, age categories, personality traits, intent to share personal information online, and online privacy behaviors. Implications for child and young teen online privacy policy are offered.
T1 and T2 Mapping for Characterization of Mediastinal Masses: A Feasibility study
Authors: Beck Kyongmin S. , Chang Suyon , Hyun Kwanyong , Sung Yeoun Eun , Lee Kyo-Young , Jung Jung Im
Published: March 2023

Purpose: To evaluate the feasibility and usefulness of T1 and T2 mapping in characterization of mediastinal masses. Methods: From August 2019 through December 2021, 47 patients underwent 3.0-T chest MRI with T1 and post-contrast T1 mapping using modified look-locker inversion recovery sequences and T2 mapping using a T2-prepared single-shot shot steady-state free precession technique. Mean native T1, native T2, and post-contrast T1 values were measured by drawing the region of interest in the mediastinal masses, and enhancement index (EI) was calculated using these values. Results: All mapping images were acquired successfully, without significant artifact. There were 25 thymic epithelial tumors (TETs), 3 schwannomas, 6 lymphomas, and 9 thymic cysts, and 4 other cystic tumors. TET, schwannoma, and lymphoma were grouped together as “solid tumor,” to be compared with thymic cysts and other tumors (“cystic tumors”). The mean post-contrast T1 mapping ( P < .001), native T2 mapping ( P < .001), and EI ( P < .001) values showed significant difference between these two groups. Among TETs, high risk TETs (thymoma types B2, B3, and thymic carcinoma) showed significantly higher native T2 mapping values (P = .002) than low risk TETs (thymoma types A, B1, and AB). For all measured variables, interrater reliability was good to excellent (intraclass coefficient [ICC]: .869∼.990) and intrarater reliability was excellent (ICC: .911∼.995). Conclusion: The use of T1 and T2 mapping in MRI of mediastinal masses is feasible and may provide additional information in the evaluation of mediastinal masses.
Vitamin D Insufficiency is Associated with Higher Incidence of Dementia, a Large Community-Based Retrospective Cohort Study
Authors: Kiderman David , Ben-Shabat Niv , Tsur Avishai M. , Anis Saar , Watad Abdulla , Cohen Arnon D. , Paz Ziv , Amital Howard
Published: March 2023

Introduction

Active metabolite of vitamin D has neuro-immunomodulatory and neuroprotective properties. However, there is still a debate about the potential association between low serum levels of hydroxy-vitamin D and increased risk for dementia.

Objectives

To determine an association between hypovitaminosis D and dementia for different 25-hydroxyvitamin-D (25(OH)D) serum level cutoffs.

Methods

Patients were identified utilizing the database of Clalit Health Services (CHS), the largest healthcare provider in Israel. For each subject, all available values of 25(OH)D during the study period, which lasted from 2002 to 2019, were obtained. Rates of dementia were compared across different cutoffs of 25(OH)D levels.

Results

Cohort included 4278 patients, of whom 2454 (57%) were women. The mean age at the beginning of follow-up was 53 (±17). During the 17-year study period, a total of 133 patients (3%) were diagnosed with dementia. In a fully adjusted multivariate analysis, the risk for dementia was almost 2-fold higher in patients with an average of vitamin D insufficiency (<75 nmol/l) measurements (OR = 1.8, 95% C.I. = 1.0-3.2) compared to reference values (≥75 nmol/l). Patients with vitamin D deficiency (<50 nmol/l) demonstrated higher rates of dementia (OR = 2.6, 95% C.I. = 1.4-4.8). In our cohort, patients were diagnosed with dementia at a younger age in the deficiency (77 vs. 81 P-value = 0.05) and the insufficiency groups (77 vs. 81 P-value = 0.05) compared to the reference values (≥75 nmol/l).

Conclusion

Insufficient levels of vitamin D are associated with dementia. Dementia is diagnosed at a younger age in patients with insufficient and deficient vitamin D levels.
The effect of thermal and cryogenic environments on the impact performance of aluminum-glass fibers/epoxy laminated composites
Authors: Askari Mohammad , Javadi Mehrdad , Eslami-Farsani Reza , Geranmayeh Abdolreza
Published: March 2023

In this research work, the effect of various environments on the impact properties of fiber metal laminates was investigated. To do so, in the first step, the 2024 aluminum layers were surface modified with the etching method. Then, the various glass fibers/epoxy composites with the configurations of (0°/0°/0°/0°, 90°/90°/90°/90°, +45°/−45°/−45°/+45° and 0°/90°/90°/0°) were sandwiched between two aluminum sheets. In the following, these samples were aged under thermal cycling (between 25 and 100 °C), isothermal aging at the temperature of 100°C, cryogenic cycling (between −196 and 25 °C), and cryogenic isothermal aging at the temperature of −196°C. To understand the effect of various aging methods on the mechanical features of these structures, the Charpy impact test was performed. Also, the failure mechanisms and related phenomena were assessed by visual observations and microstructural investigations. In the first steps of thermal aging, the impact strength of FMLs was improved, which the highest of that being 46.9%. In the higher cycles or exposing times, the impact strength showed reducing trends, due to thermal degradations of the epoxy matrix. The cryogenic cycling in the high cycles reduced the impact strength of FMLs. But in the cryogenic isothermal condition, in some cases, the improvement in the impact strength was seen, which the highest of that being about 43.4%.
Hybridization effect of Kevlar and glass fibers on CFRP composite under low velocity impact: Numerical simulations
Authors: Kaware Kiran , Kotambkar Mangesh
Published: March 2023

Present work aimed to investigate the hybridization effect of Kevlar and glass fibers to enhance the impact performance of CFRP composites under low velocity by numerical analysis. Analyzing the stack sequencing of Kevlar and glass fibers becomes essential to improve the impact resistance of CFRP composite structures. It is important to know the dynamic behavior of hybrid composites under LVI. To get the best possible stack sequence, numerical simulations were carried out on different stacking sequence combinations of Kevlar and glass with carbon fiber epoxy composites for 25 J energy levels. A virtual drop weight impact test conditioned numerical model created in Abaqus software mimics the actual intralaminar and interlaminar failure. Intralaminar models based on continuum damage mechanics and interlaminar, that is, delamination failure based on cohesive modeling used to evaluate the damage development and material behavior. From the obtained simulation results, the hybrid composites having Kevlar fibers exhibited superior impact resistance.
Effect of microwave sintering on the microstructure and mechanical properties of Al-Al2O3-Si3N4 hybrid composite fabricated by powder metallurgy techniques
Authors: Dwivedi Shashi Prakash
Published: March 2023

In the present investigation, Si3N4 has been used in the partial replacement of SiC with Al/Al2O3 composite for the application in the automobile industries parts. A microwave sintering technique was employed for the processing of the composite. The aluminum-based composite was developed with the constant 5 wt.% of Al2O3. The weight percent of Si3N4 increased from 2.5% to 7.5%. Uniform distribution of the reinforcement particles was observed for the composition Al-5 wt.% Al2O3 − 2.5 wt.% Si3N4 composite and Al-5 wt.% Al2O3 − 5 wt.% Si3N4 composite. Optical microscope images Al-5 wt.% Al2O3 − 5 wt.% Si3N4 composite showed that the dispersion of the reinforcement (Al2O3 and Si3N4) has been done in a very fine and dense manner. Dispersion of reinforcement in a very dense manner helped in enhancing the mechanical properties of the composite. EDX pattern of Al-5 wt.% Al2O3 − 5 wt.% Si3N4 composite showed the maximum weight percentage of an element of Al, followed by Si, O, and N. Minimum porosity was found to be 0.045% for the composition Al-5 wt.% Al2O3 − 2.5 wt.% Si3N4. However, the percent porosity of the Al-5 wt.% Al2O3 − 5 wt.% Si3N4 was 0.072%. The hardness, compressive strength, and tensile strength of aluminum were improved by about 82.85%, 18.94%, and 62.60% respectively with respect to aluminum after adding 5 wt.% Al2O3 and 5 wt.% Si3N4. XRD of the Al/Al2O3/Si3N4 composite showed the presence of Al, Al2O3, Si3N4, MgAl2O4, and Al2Cu phases. Thermal expansion and corrosion behavior were also observed to identify the Al2O3 and Si3N4 addition effect in the aluminum alloy.
Modeling of modified Eyring–Powell nanofluid flow subject to thermal-solutal stratification phenomenon
Authors: Khan Waqar Azeem
Published: March 2023

Population growth and rapid industrialization have led to many serious problems such as change in climate, fossil fuel shortages, crisis of energy, and environmental issues, which have become the primary risks for the survival of human being on this planet, to overcome these problems researchers take keen interest in nanofluid because they have a higher thermal conductivity than conventional base fluids, and thus can serve as an effective heat transfer medium. In present article, the impact of magnetized flow for modified Eyring–Powell fluid under thermophoretic and Brownian movements aspects is examined. Double stratification phenomenon for heat/mass transportation analyses is introduced. Some suitable similarity transformations are exploited to achieve the non-linear ODEs. The acquired ODEs are resolved numerically by using bvp4c technique. Moreover, physical elucidation for dimensionless variable's is presented. Velocity of modified Eyring–Powell nanofluid has opposite behaviors versus magnetic parameter and fluid parameter. Augmented values of radiation parameter, thermophoresis, thermal Biot number, and magnetic parameters intensify the temperature of nanofluid. More specifically, concentration of nanofluid dwindles against larger solutal Biot number and Brownian moment parameter. Transportation rate of heat intesifies for larger [Formula: see text].
Experimental investigation on the mechanical performance of the Al2O3 and ZrO2 added Al-Mg-Si alloy for structural applications
Authors: Ogunsanya Olusegun Adebayo , Adewale Akinwande Abayomi , Raj Mohan R , Talabi Henry , Saravana Kumar M , Vignesh M , Bhowmik Abhijit
Published: March 2023

The present-day structural application requires advanced materials at extreme conditions, and the development of it is not economically feasible. As a result, existing material in the composite form has more visibility to suit the purpose. The material's strengths and qualities must be examined before it can be recommended for use in harsh conditions. In the present study, Al2O3 (3, 6, 9, 12, and 15 wt.%) and ZrO2 particles (2 wt.%) are reinforced with Al-Mg-Si alloy (Al 6061), which possess good isotropic behaviour and better interface bonding. The double stir casting process was adopted for the hybrid composite development, and the samples were cold rolled to reduce grain size and pores in the composites. The developed composites were subjected to mechanical characterisation tests such as hardness, tensile, compression, impact and flexural tests. An increase in reinforcement percentage enhances the mechanical properties. The improvement was attributed to the high thermal mismatch and reduction in the inter-particle distance by cold rolling and the reinforcements. Scanning electron microscope microstructural examination was conducted, and even dispersion of 3 to 15 wt.% Al2O3 reinforcements was observed. Tensile elongation decreases with an increase in reinforcement percentage. High elastic modulus and temperature mismatch between matrix and reinforcements increase the strength of the composites. The fracture behaviour of the composites generally showed dimples which are characteristics of ductile fracture, except at 15 wt.% Al2O3 / 2 wt.% ZrO2 showed a large portion of cleavage planes and grain cracking. The Al-Mg-Si alloy is reinforced with 9 wt%. Al2O3 / 2 wt.% ZrO2 had the best properties suitable for its use in different structural applications.
Detecting and monitoring incontinence associated dermatitis: Does impedance spectroscopy have a part to play?
Authors: Owen Emily J , Heylen Rachel A , Stewart Kyle , Winyard Paul G , Jenkins A Toby A
Published: March 2023

In this review, current understanding of the prevention and treatment of Incontinence Associated Dermatitis (IAD) is discussed. The need for preventative measures which target specific faecal/urinary irritants is highlighted, including the role of urease inhibitors. There is no existing internationally and clinically accepted method to diagnose and categorise the severity of IAD. Diagnosis currently relies on visual inspection; non-invasive techniques to assess skin barrier function could remove subjectiveness, particularly in darker skin tones. Impedance spectroscopy is a non-invasive technique which can be used to monitor skin barrier function, supporting visual assessments. Six studies (2003–2021) which used impedance to assess dermatitis were reviewed; inflamed skin was distinguishable from healthy skin in each case. This suggests that impedance spectroscopy could be useful in diagnosis early-stage IAD, potentially enabling earlier intervention. Finally, the authors present their initial findings on the role of urease in skin breakdown in an in vivo IAD model, using impedance spectroscopy.
On PVDF composite as partially absorbable smart implants
Authors: Husain Minhaz , Singh Rupinder , Pabla Bahadur Singh
Published: March 2023

For various orthopedic needs, several studies have been testified on non-absorbable implants, prepared with different metals/alloys, and composites. But yet little has been stated on the partially absorbable smart implants of thermoplastic composites for online health monitoring of veterinary patients. This article highlights the in-house development of affordable, polyvinylidene fluoride (PVDF) composite-based partially absorbable smart implants (with online sensing capability) for orthopedic needs in canines. Hydroxyapatite (HAp) and chitosan (CS) nanoparticles were reinforced in the PVDF matrix by a melt processing route with various weight proportions (wt.%) to fabricate a partially absorbable smart implant for the canine. The study suggests that the 8.0 wt.% HAp and 2.0 wt.% CS in PVDF is the superlative composition/proportion of reinforcement for preparing feedstock stock filaments (for 3D printing of partially absorbable smart implants), based on rheological, mechanical, thermal, dielectric, and voltage-current-resistance ( V- I- R) characteristics. For the selected composition/proportion of PVDF composite, acceptable mechanical properties (such as modulus of toughness (MoT) 2.0 MPa, Young’s modulus (E) 889 MPa), and dielectric properties (dielectric constant (ε r) 9.6 at room temperature (30°C) and 20 MHz) for online sensing capabilities (for health monitoring) was observed. The results are braced by attenuated total reflection Fourier transform infrared (ATR-FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) analysis.
Mechanism analysis and uncertainty quantification of blade thickness deviation on rotor performance
Authors: Chu Wuli , Ji Tianyuan , Chen Xiangyi , Luo Bo
Published: March 2023

The blade thickness distribution is an important geometric parameter of a compressor rotor blade. It determines the aerodynamic performance of a rotor, which should be carefully designed. However, the manufacturing inaccuracies cause the blade thickness distribution to deviate from the ideal design. These geometric deviations alter the flow field near the blade surface, which affects the aerodynamic performance of the rotor. Therefore, it is of great significance to quantitatively investigate the effects of blade thickness deviation on the aerodynamic performance. In this paper, the influence of blade thickness deviation on the flow field is analyzed based on a transonic compressor rotor, and an uncertainty quantification process is performed to study the effects of blade thickness deviation on the aerodynamic performance. Cases with different geometry features are checked in the current study using 3-dimensional Reynolds-averaged Navier–Stokes simulations. Results show that the blade thickness deviation leads to changes in the intensities of the expansion wave in the upper part of the blade suction and the passage shock wave, which affects the supercharging process of the rotor. The influence of thickness deviation on the strength of the tip leakage vortex changes the isentropic efficiency of the rotor. The results of the uncertainty quantitative analysis indicate that the linear correlation between the variation of rotor performance and the thickness deviation is strong when the machining accuracy is high, whereas the linear correlation between the two is weakened when the tolerance range is larger.
Delusions as Epistemic Hypervigilance
Authors: McKay Ryan , Mercier Hugo
Published: March 2023

Delusions are distressing and disabling symptoms of various clinical disorders. Delusions are associated with an aberrant and apparently contradictory treatment of evidence, characterized by both excessive credulity (adopting unusual beliefs on minimal evidence) and excessive rigidity (holding steadfast to these beliefs in the face of strong counterevidence). Here we attempt to make sense of this contradiction by considering the literature on epistemic vigilance. Although there is little evolutionary advantage to scrutinizing the evidence our senses provide, it pays to be vigilant toward ostensive evidence—information communicated by others. This asymmetry is generally adaptive, but in deluded individuals the scales tip too far in the direction of the sensory and perceptual, producing an apparently paradoxical combination of credulity (with respect to one’s own perception) and skepticism (with respect to the testimony of others).
Response Durations: A Flexible, No-Cost Tool for Psychological Science
Authors: Pfister Roland , Neszmélyi Bence , Kunde Wilfried
Published: March 2023

Response durations for simple key presses are an easily available but heavily underused measure. Whereas response times dominate the toolbox of experimental psychologists and cognitive modelers alike, any study with standard key-press responses also allows for the measurement of such durations as the time from response onset to response offset. Moreover, response times and durations are decidedly independent, so response durations hold great promise as a means to uncover unique perspectives on cognitive processing. We showcase recent observations and corresponding theoretical frameworks to highlight that this inconspicuous measure deserves much more attention than it has attracted so far. Given that it comes at no extra cost for common experimental setups, any researcher is well advised to consider adding the measure of response duration to their empirical toolbox.
A Single Imperial Army? The Development of Australian Army Staff Training in an Imperial Context, 1919–1939
Authors: Farquharson Iain
Published: March 2023

This article examines the development of Australian staff training across the interwar period. Focussing on the establishment of the Australian Command and Staff School in Sydney in 1938, this article argues that whilst still relying on British educational institutions, the Australian Army developed its own progressive form of officer education which reflected British and Dominion educational lessons from the First World War. By doing so, this article challenges our understanding of the interconnectivity of imperial forces and proposes a more nuanced, networked approach to officer training across the interwar period accounting for local defence priorities and national policies.
Governing Oneself Through HIV Diagnosis to Antiretrovirals
Authors: Nkomo Nkululeko
Published: March 2023

The article focuses on the experience of reinventing oneself post HIV diagnosis when living on antiretrovirals. Six women and men enlisted for antiretrovirals in South African public health facilities were interviewed, and a qualitative analysis was conducted drawing on Foucault’s theory of governmentality. For the participants, the prevailing governing rationality of taking personal responsibility for their health is synonymous with self-recovery and restoration of self-determination. From the hopelessness and despair of HIV diagnosis, for all six participants, committing to antiretrovirals enhances their capacity to take back control of their transformation from victim to survivor, and with it, a sense of personal integrity. Yet, an unwavering resolve to use ARVs is not always possible for some of them, is not preferable or is not always desirable, which perhaps signals that for certain people living with HIV, their life-long journey of self-governance with ARVs is likely to be characterized by constant contradictions.
Finnish Translation and Linguistic Validation of the CLEFT-Q Questionnaire
Authors: Westerlund Mikael , Heliövaara Arja , Leikola Junnu , Homsy Pauliina
Published: March 2023

Objective

Cleft lip and/or palate (CL/P) can have long-lasting effects on the appearance, function, and psychosocial wellbeing of patients. The CLEFT-Q questionnaire is a patient-reported outcomes instrument specifically designed to assess the health-related quality of life of patients with CL/P. The aim of this study was to produce and linguistically validate a Finnish version of the CLEFT-Q questionnaire.

Design

The CLEFT-Q questionnaire was translated into Finnish following guidelines of the International Society for Pharmacoeconomics and Outcomes Research. Pilot testing with cognitive debriefing interviews was conducted on patients of the target age range of the questionnaire, 8–29, and with various cleft types.

Results

The CLEFT-Q questionnaire translated readily into Finnish. A review of the backward translation led to two words being changed. Thirteen patients – ten females and three males – with a median age of 14 years, participated in the cognitive debriefing interviews. The interviews led to further nine word changes. The pilot study data suggested that the performance of the Finnish version of the instrument is in line with the original CLEFT-Q questionnaire.

Conclusions

The Finnish version of CLEFT-Q produced here is linguistically valid and ready for use in the evaluation of the health-related quality of life of patients with CL/P. However, future work is needed to further assess the validity and the reliability of the CLEFT-Q in the Finnish patient population.