bluuebunny/crossref_metadata_2025 huggingface dataset:
Coordinated modeling in object oriented analysis and design using the system coordination diagram
Authors:   , Stringer Gail G. , Song Il-Yeol
Published: July 2024

Object-oriented application development methodologies provide structure for software development. This thesis presents enhanced modeling techniques and associated graphical presentation methods (the System Coordination Diagram) which address limitations of currently available methodologies. The diagram is intended to be incorporated into development projects using common methodologies. The primary limitations of existing methodologies are related to the fragmented nature of the model produced by most methodologies, due to the modeling of the system using separate, independent, views. There is no clear layering of the model to show various levels of granularity. The implications of the behavior of one object on the behavior of other objects, and the coordination of concurrent activity, in order to assure system consistency, are inadequately modeled. There is also a need for better support for consistency and completeness checking. These limitations are addressed by the System Coordination Diagram. The System Coordination Diagram is a layered diagram which combines object behavior and object interaction in one diagram. It connects the model from the general high level overview, to the detailed low level view. It provides explicit connections to the other diagrams in the methodology being used, and provides a framework into which the separate parts of the developing model can be placed. These modeling techniques can be applied to Use Case modeling, providing a useful graphical presentation. The contributions of this work include: Modeling techniques which produce a complete and coherent single model out of the numerous views of the system under development; Coordination of development along three axes-level of granularity layers, among the views at each level of detail, and through the development life-cycle (from analysis through design to implementation); End-to-end process modeling representation of global processes that impact many objects and involve numerous intermediary steps between initiation and conclusion; Facilitation of completeness and consistency checking; Representation of the relationships between object communication and behavior and the impacts the behavior of objects have on the behavior of other objects, which facilitates the identification of conflicts and errors of omission.
The Age-Dependent Effects of a Therapeutically-Relevant Dose of Methylphenidate on the Juvenile Rat Prefrontal Cortex
Authors:   , Urban Kimberly R. , Gao Wen-Jun
Published: July 2024

Methylphenidate (MPH) is the most frequently prescribed medication for treatment of attention deficit/hyperactivity disorder (ADHD) and as a cognitive enhancer in healthy individuals. Despite its long history of usage, the cellular effects of treatment on juvenile brains are not well understood. In this thesis, we examine the effects of a clinically relevant dose of methylphenidate on the functions and plasticity of juvenile rat prefrontal cortical neurons. A single dose or chronic treatment significantly decreased neuronal excitability of layer 5 pyramidal neurons and excitatory synaptic transmission through activation of hyperpolarization-activated cyclic nucleotide-gated (HCN) channels; this effect was not fully reversible when dosage was off-limit. These results suggest that the juvenile brain is hypersensitive to MPH; if a hyperdopamine state is induced in juvenile brains, plasticity is likely to be damaged through decreases in NMDAR-NR2B subunits. Indeed, levels of NR2B were significantly decreased following MPH treatment, and this decrease translated to a deficit in short-term plasticity. Longterm plasticity, however, was shifted in favor of long-term potentiation, with a decrease in depression. The GABA-ergic inhibitory interneuron activity was increased by MPH treatment, indicating a cell-type-specific action of MPH. In conclusion, this work suggests that the juvenile brain may be hypersensitive to MPH, and that dosing regimens need to be very carefully titrated for age as well as weight. In addition, our data present a novel mechanism of action of methylphenidate; namely, shifts in the glutamatergic receptor balances, and highlight potential risks to prefrontal cortical development and plasticity. Key words: methylphenidate, psychostimulant, prefontal cortex, juvenile, ADHD, electrophysiology. Abbreviations: MPH = methylphenidate, PFC = prefrontal cortex, EPSC = excitory postsynaptic current, IPSC = inhibitory postsynaptic current, LTP long-term potentiation, LTD = long-term depression, AMPA = [alpha]-amino-3-hydroxy-5-methyl-4-isoxazolepopionic acid receptor, NMDA = n-methyl-d-asparate receptor, GABA = [gamma]-Aminobutyric acid.
The role of parametric demodulation and the quadratic property in human amplitude-modulated ultrasonic hearing
Authors:   , Zeng Shengke , Beard Richard B
Published: July 2024

This dissertation studies the roles of parametric demodulation model and two physical demodulation models, the rectifying amplitude demodulation model and the coherent amplitude demodulation model in human amplitude-modulated (AM) ultrasonic hearing. The parametric demodulation of focused AM ultrasound with Gaussian distribution and diffraction in dissipative media was modified and computed in order to study parametric demodulations of a set of monotone focused AM ultrasound in human auditory system. This set of monotone AM ultrasonic modes (standard AM mode, carrier-suppressed AM mode and square-root AM mode) was selected as the stimuli for human tests, in order to provide distinct and simple frequency patterns of demodulations in the three physical demodulation models. The predicted frequency patterns of parametric demodulations of these AM ultrasonic modes were obtained in parametric demodulation measurements. These frequency patterns were partially observed in human auditory sensation in response to the stimulation of the same AM ultrasonic modes. The analysis of these observed frequency patterns indicates the existence of quadratic property in human AM ultrasonic hearing. Parametric demodulation is determined by this analysis to have a joint influence in conjunction with the quadratic rule on human AM ultrasonic hearing, while the rectifying amplitude demodulation and the coherent amplitude demodulation are determined to be irrelevant to ultrasonic hearing. The square-root pre-conditioning in verbal-modulated ultrasonic stimulation in human subject tests were proved to be effective in improving the quality of verbal recognition in verbal-modulated ultrasonic hearing.
Mechanisms of activity-dependent plasticity after spinal cord injury and the role of proprioceptive stimulation
Authors:   , Keeler Benjamin Emerson , Houle John D
Published: July 2024

Recovery following spinal cord injury (SO) is attributable to the innate plasticity of the nervous system and retention of spinal circuits involved in locomotion and other behaviors. Repetitive patterned activity in the form of exercise improves this recovery by increasing local neurotrophic factor levels and axon sprouting in the spinal cord and by minimizing possible adverse effects of spinal cord plasticity. To better understand the underlying features of activity-dependent plasticity, we analyzed molecular changes in the spinal cord resulting from a passive exercise regimen. In doing so, we paid special attention to the role of the sensory system in modulating the molecular response and reflex activity of neurons below the level of injury. First, we examined changes in mRNA expression following injury and exercise in cells of the motor system and proprioceptive sensory system, with emphasis on genes associated with the injury response and with neurotrophic factors because of their ability to modify neural circuits. Exercise increased the expression of genes associated with survival and reduced those associated with apoptosis. Exercise increased expression of the neurotrophic factors, but only in cells of the motor system. To determine if sensory input was necessary for reflex normalization seen with exercise after SCI, we used pyridoxine (toxic to large, sensory neurons) to block proprioceptive sensory input. Hyperactive reflexes associated with SCI were not normalized in exercised animals treated with pyridoxine, demonstrating a critical role of proprioceptive stimulation in modulation of the H-reflex. Further, immunohistochemical analysis of synaptic elements below the level of the injury indicated no change with exercise after pyridoxine administration. Next, we examined the role of sensory stimulation in molecular changes observed with exercise. We analyzed gene expression in motoneurons, after SCI and exercise, in animals lacking either proprioceptive sensory stimulation or all sensory stimulation caudal to the injury. Exercise failed to increase expression of neurotrophic factors in motoneurons in either state of sensory loss. Overall these results demonstrate possible molecular mechanisms and the critical role of proprioceptive input in activity-dependent plasticity.
Executive function in Turner Syndrome
Authors:   , Romans Sarah Magnuson
Published: July 2024

Turner syndrome, a genetic disorder affecting girls, has a well described neurocognitive profile including difficulty with visual-spatial processing and attention skills. The goal of the current study was to investigate executive function and attention abilities in females with Turner Syndrome (TS). Executive skills include the ability to plan, organize, monitor, and execute multi-step problem solving processes. Measures of attention, visual-spatial and perceptual skills, language, and executive function were analyzed from 130 girls with Turner Syndrome and from 208 female controls matched for age, IQ, and SES. Three age groups were evaluated in order to assess developmental patterns in executive skills. TS girls performed at levels comparable to controls on tasks involving hypothesis generation and mental flexibility (e.g., the Wisconsin Card Sort Test), but demonstrated relative difficulty on a measure of verbal fluency, and on measures involving working memory (e.g., Tower of Hanoi) and organizational components (e.g., Rey-Osterrieth organization). While age-related improvement was demonstrated on all measures of executive function, no interactions were found between age and study group. TS girls showed a developmental trend relative to controls on the WCST that may suggest a developmental lag in the acquisition of efficient hypothesis testing. In consideration of developmental factors of executive function identified in normal controls, TS females performed at comparable levels to controls, and it is likely that these developmental factors do not accurately describe executive function in TS females. Because of the functional heterogeneity of executive function in children and adolescents, the explanation for these findings is uncertain. One possible explanation is that the difficulty in executive function may be due in part to weaknesses in visual-spatial planning and organization, and/or to weaknesses in attention. As results suggest TS females may demonstrate a weakness in verbal fluency as well, further exploration of the performance of TS females on executive tasks that minimize involvement of previously described TS associated deficits is warranted. Future investigation will enable us to more thoroughly understand the contribution of multi-modal factors, and the resulting neurocognitive profile, in individuals with Turner Syndrome.
Tweet it, post it, message it
Authors:   , Lieberman Jerre D. , Giddings Amy
Published: July 2024

The topic of social media as a 21st century communication tool is prominent throughout many aspects of business and many different business industries. For sport teams and organizations, implementing social media is an effective tool for ticket sales customer relations management and to increase ticket sales revenue. The purpose of this study was to examine how sport organizations are using the tool of social media with regards to ticket sales and the ticket sales staff, and to find out if there is any belief to the correlation between the ticket sales revenue generated by ticket sales staffs and their use of social media by ticket sales staff members. Ticket sales professionals were offered the chance to give their opinions on the future use of this emerging communication technology in the hope of increasing customer relationships between ticket buying consumers and ticket sales professionals. In order to get a sample of opinions about the use of social media in the ticket sales profession, an electronic survey was sent out using the social media website Linkedln. Participants ranged from aspiring ticket sales professionals, entry level-ticket sales professionals, and ticket sales managers. Survey questions were proposed to find out the current strategies of social media usage, and what future strategies would help increase ticket sales in the future. Five of the questions were demographic, multiple choice questions. Three questions asked about current social media usage by ticket sales professionals. Six of the questions were qualitative, open ended questions. Using these responses, the qualitative data was broken down into themes in regards to the use of social media by the ticket sales professionals. Professional and collegiate sports teams are looking for ways to increase ticket sales. With the threat of simply staying at home and watching the game, teams are struggling to gets fans to show up to their respective games. Professional teams have also placed an emphasis on retaining their ticket buying customers. Social media can be the new communication tool for professional and collegiate ticket sales professionals to increase revenue and effectively manage their relations with customers.
A three-dimensional device simulator for the analysis of the MOS-SOS edge parasitic transistor
Authors:   , Rios Rafael , Rothwarf Allen
Published: July 2024

Typical MOSFET devices fabricated with the silicon-on-sapphire (SOS) process have an inherent parasitic transistor at the island edge. The effect of the parasitic transistor cannot be ignored for narrow width devices. In addition, the edge parasitic effects become more pronounced after exposure to ionizing radiation. To correctly model the effect of the parasitic transistor, a three-dimensional device simulator has been developed in this work. The code is based on a numerical solution of the semiconductor equations in three dimensions using the seven-point finite differences method. Up-to-date models for the physical parameters are employed, including new depth dependent models for the carrier mobilities and lifetimes to account for the degradation near the back interface characteristic of SOS films. The difficulties in solving the semiconductor equations for devices with floating regions are discussed. Efficient iterative solvers, preconditioned with incomplete LU factorization, are implemented to solve the large linear system of algebraic equations resulting from the 3-D discretization. A novel strategy, applicable to any MOS-SOI structure, has been developed to reduce the CPU time and memory requirements. This strategy allows calculation of full I-V device characteristics on a VAX/8800 computer, without resorting to a supercomputer or special vector/parallel machine. The model equations and the numerical solutions are validated by showing the close agreement between calculated and measured device characteristics in the subthreshold, linear, saturation, and "kink" region. The importance of 3-D simulations to calculate the I-V characteristics of narrow channel devices is shown. Radiation effects are modeled by adding distributions of charges at the silicon/insulator interfaces. The high value and variability of the radiation-induced leakage current observed in practice are explained with a simple back interface charge distribution model.
Pre and post combustion hydrocarbon oxidation studies related to engine knock and emissions
Authors:   , Prabhu Srinivasa Kruthyventi
Published: July 2024

Higher engine efficiencies and lower exhaust emissions are the two major goals of the automotive research community. In this thesis, pre combustion oxidation related to engine knock and efficiency and post combustion oxidation related to hydrocarbon emissions have been studied. The oxidation chemistries of two primary reference fuel blends with octane numbers of 87 and 92 were examined in a motored engine at low and intermediate temperatures (<1000 K). Based on the reactivity mapping and time resolved in-cylinder sampling experiments the current understanding of the oxidation mechanism was tested and important reaction pathways were identified. In order to improve our understanding of olefin autoignition chemistry, experiments were conducted with 1-butene and 1-pentene in a high pressure flow reactor. As the widely accepted reaction mechanisms failed to explain the reactivity and product distribution, hydrogen abstraction and oxygen addition reactions similar to alkane chemistry were proposed and supported by kinetic analysis. This constitutes a significant improvement to the olefin autoignition chemistry. Since nitric oxide (NO) is present in the end gases of engines, its effect on hydrocarbon oxidation and autoignition was examined in an engine and a pressurized flow reactor. The engine results with primary reference fuel blends showed that NO can enhance reactivity in the negative temperature coefficient region and cause autoignition. This was the first reported result showing the effect of NO on engine autoignition (Prabhu, et al., 1993). A chemical basis for this interaction was also proposed. Hydrocarbon emissions from spark ignited engines are formed when a fraction of the fuel escapes combustion and is exhausted along with the burned gases. Post combustion oxidation of this fuel, in the cylinder and exhaust port, plays an important role in determining exhaust hydrocarbon emission levels. Experiments were conducted with seven gaseous fuels and their blends to identify the factors controlling post combustion oxidation. Subsequently, detailed time resolved exhaust port sampling experiments were conducted to examine the sample composition and importance of oxidation at various stages of the exhaust process. The time resolved data showed that the post combustion oxidation levels are high in the gases exiting the cylinder in the blowdown process and decrease significantly in the exhaust stroke.
Effects of dietary fatty acids on the production and properties of apoprotein B-containing lipoproteins of rat hepatoma MCA-RH7777 cells
Authors:   , Kummrow Emma , Fisher Edward A.
Published: July 2024

Atherosclerosis is the major cause of death in Western societies. Positive correlations have been established between plasma levels of apoprotein B (apoB) and the development of atherosclerosis. Also, correlations between amount and types of fat in the diet and plasma cholesterol levels have been demonstrated. In this study, we have sought to use an in vitro system to conveniently test effects of individual dietary fatty acids on hepatic apoB production. We have chosen the rat hepatoma cell system, McA-RH7777 for this purpose due to its ability to both vigorously secrete lipoproteins in all density classes and, in limited previous studies, to respond to fatty acids in ways similar to more intact systems, such as animals and human subjects. Experiments were conducted in which McA-RH7777 cells were incubated for 6 hours with 0.8 mM dietary fatty acids complexed to BSA in a 5:1 molar ratio, or an equimolar amount of BSA alone. Of the fatty acids tested in this manner, lauric acid (12:0), stearic acid (18:0), oleic acid (OA, 18:1) and linoleic acid (18:2) did not affect secretion of newly-synthesized apoB, compared to incubation with BSA alone. Myristic acid (MA, 14:0) and palmitic acid (16:0) increased total newly-synthesized apoB secretion by 54% and 35%, respectively, compared to BSA alone. Docosahexaenoic acid (DHA, 22:6) decreased total newly-synthesized apoB secretion by 68%. Fatty acid effects on apoB secretion were not due to effects on triglyceride or protein synthesis. Pulse-chase analysis showed the promotion of apoB100 secretion by MA to be due to decreased intracellular degradation of apoB100, compared to the results for OA. With the use of protein trafficking inhibitors we found multiple sites of intracellular degradation of apoB100 which were utilized differentially after incubation with various fatty acids. That is, after incubation with MA, apoB100 was degraded in the endoplasmic reticulum when blocked in that compartment while incubation with OA led to apoB100 degradation in a post-ER compartment. Further experimentation showed that incubation with MA, while increasing apoB100 secretion and not affecting triglyceride synthesis, decreased secretion of newly- synthesized triglycerides. After incubation with MA, conditioned media were subjected to density gradient ultracentrifugation, and the majority of the apoB-containing lipoproteins were recovered at densities from 1.063 to 1.117 g/ml. Thus, incubation of McA-RH7777 cells with MA led to the secretion of a dense, triglyceride-poor apoB-containing lipoprotein. We conclude that fatty acids can regulate both the amounts and physical characteristics of apoB-lipoproteins produced by liver cells by affecting apoB degradation and its association with lipids.
A theory of behavioral alterations in dementia
Authors:   , Lamar Melissa , Spiers Mary Virginia
Published: July 2024

Behavioral change in dementia is a topic that has enjoyed a recent resurgence in the literature. Despite clinical and descriptive advances, theoretical gains have been limited. The present study proposed a theory of behavioral alterations, i.e., unawareness and psychosis, based on a continuum anticipated by early impairments of visuospatial and attentional abilities. Participants (N = 32; mean age of 76.5±6.27), were grouped according to scores on an awareness questionnaire. A measure of global-local processing assessed perceptual biases and a covert orienting of visual attention task measured the engage, disengage, and move of attention. Patterns in the data suggest the unaware group (UnA) had a local processing tendency that interfered with their ability to focus on the gestalt. The UnA group showed greater difficulty controlling automatized behaviors across motor perseverative (F (1, 25) = 3.28, p = .08) and mental manipulation (F (1, 27) = 5.66, p = .02) tasks. They were also more impaired on tests of right frontal functioning when compared to the aware group. Results suggest executive dysfunction, in addition to perceptual processing tendencies, plays a role in unawareness. Revisions of current theory and implications for the development of psychosis are considered. Early detection and intervention techniques are also discussed.
The impact of sales managers' transformational leadership behaviors on the role clarity, self-efficacy, and job satisfaction of individual salespeople
Authors:   , Shoemaker Mary Eugenia
Published: July 2024

Superior sales force performance is critical to the success of most firms. Leadership behaviors or practices have been identified that when used by managers result in exceptional performance from subordinates. Kouzes and Posner labeled these practices, Challenging The Process, Inspiring A Shared Vision, Enabling Others To Act, Modeling The Way, and Encouraging The Heart. Leadership that results in exceptional performance is generally known as Transformational Leadership. This study examines the impact of these transformational leadership practices when used by first line sales managers on the key salesperson job outcomes of role clarity, self-efficacy and job satisfaction. These outcomes have been positively associated with sales force performance. The sample consists of professional industrial salespeople from electrical components manufacturers. Leadership behaviors were found to have a significant impact on the role clarity and job satisfaction of salespeople. The behaviors of Modeling the Way and Enabling Others to Act had the greatest impact on role clarity, while the behaviors of Enabling Others to Act and Encouraging the Heart had the largest impact on job satisfaction. No support was found for the effect of leader behaviors on self-efficacy. Role clarity was found to have a significant impact on job satisfaction. Within-and-between analysis (WABA) indicated that leadership behaviors are related to the group, but individual salespeople respond independently to leadership behaviors. WABA analysis also indicated no single source problem and that the dyad is the appropriate level of analysis for most of the leader behaviors.
Immobilization of enzymes in mesostructured materials via the nonsurfactant-templated sol-gel chemistry
Authors:   , Xu Jigeng , Wei Yen
Published: July 2024

We have synthesized and characterized a variety of mesoporous enzymecontaining sol-gel materials that combine the functionality of biomolecules with stability of inorganic oxides via the nonsurfactant template pathway. The enzyme molecules become immobilized in situ in mesostructured composites during the sol-gel reactions of silicon alkoxides in the presence of the nonsurfactant pore forming agent or template, such as D-glucose, D-fructose, sucrose or glycerol. Removing the nonsurfactant templates from dried as-synthesized organic-inorganic nanocomposites by water extraction yields mesoporous biogels with high remaining enzymatic activities. The catalytic activity of encapsulated enzymes, such as alkaline phosphatase, acid phosphatase or horseradish peroxidase, has been assayed and correlated with the microstructures of the host silica or organically modified silica materials derived from tetramethyl orthosilicate, tetraethyl orthosilicate or phenyltrimethoxysilane under varied synthesis conditions. Nitrogen adsorption and transmission electronic microscopy characterizations show that the sol-gel matrices obtained by removing the templates possess a three-dimensional network with interconnected mesopores. The pore structure parameters of the sol-gel matrices and the apparent catalytic activity and stability of the entrapped enzymes are closely related to and fine-tunable by the content of templates in the synthesis. The enzymes encapsulated in the nonsurfactant-templated mesoporous sol-gel materials exhibit remarkably higher apparent catalytic activity, from a few-fold to three orders of magnitude greater, than those in the nontemplated conventional microporous hosts synthesized in the absence of the templates under otherwise identical conditions. The activity improvement of enzymes in mesoporous materials over that in microporous sol-gels is believed to arise from relatively larger pore sizes, resulting in less internal diffusion resistance and steric hindrance and greater accessibility of the entrapped enzymes to the substrates. Because of confinement in the host cages, the thermal and operational stabilities of enzymes are greatly enhanced. We also have explored the use of nonionic poly(ethylene oxide) copolymer surfactants as templates for in situ immobilization of enzymes in mesostructured sol-gel materials. This study demonstrates that the novel sol-gel immobilization methods are versatile in terms of enzymes, available templates and matrix chemical compositions, leaving much room for further modifications and optimizations. The optically transparent, biologically doped sol-gel materials have potential applications in biocatalysis, biosensor devices, etc.
A Joint Bit-loading and Symbol Rotation Scheme for Multi Carrier Systems
Authors:   , Sosa Barreto Guillermo Andres , Dandekar Kapil R
Published: July 2024

Multi-carrier systems have become the core of many communication systems. For the last 50 years, researchers have constantly been refining such solutions to convey large amounts of information. In this thesis, two problems are addressed; i) high peak to average power ratio (PAPR) in multi-carrier systems and ii) throughput improvement in multi-carrier systems by PAPR-aware rate adaptive bit loading. The first issue is one of the biggest drawbacks of Orthogonal Frequency Division Multiplexing (OFDM) systems and the second aims to improve the system data rate in scenarios where the communication system adapts to environmental channel conditions. Towards this goal, two symbol rotation-inversion algorithms that reduce the peak to average power ratio in multi carrier OFDM systems are implemented on a software defined radio platform. One is evaluated in a single input single output (SISO) OFDM system and the second in a multiple input multiple output (MIMO) OFDM communication system. Results from both algorithms show the benefit of PAPR reduction and motivate the proposed novel solution. A new scheme that combines the benefits of bit allocation and symbol rotation to reduce the PAPR is presented, simulated and evaluated. It is demonstrated in simulations by means of post processing signal to noise ratio (PPSNR), throughput and bit error rates, how this new framework succeeds in achieving higher data rates in a more robust way. PAPR remediation in OFDM communication systems can dramatically improve PPSNR and thus improve system range and robustness to noise. When coupled with adaptive bit loading techniques, these PAPR remediation strategies can substantially increase link throughput. For a fixed number of permutations, measurements showed PPSNR improvements of 2dB in SISO OFDM and almost 1dB in MIMO OFDM. Simulations showed that symbol rotation results in more than one order of magnitude BER reduction for SISO OFDM and one order of magnitude reduction in MIMO OFDM. These techniques thus have the potential to significantly improve future multi-carrier communication systems.
Percepciones en el alumnado de 1º de bachillerato sobre dilemas bioéticos en salud: influencia en sus destrezas en argumentación y pensamiento crítico
Authors: Calavia Lombardo Sergio , Bravo Torija Beatriz , Mazas Gil Beatriz
Published: July 2024

Este trabajo presenta los resultados del análisis de contenido de una entrevista realizada a seis alumnos de 1º de bachillerato tras realizar una secuencia de enseñanza-aprendizaje para trabajar la argumentación y el pensamiento crítico a través de controversias sociocientíficas sobre salud con componente bioético. El objetivo es identificar la percepción de los alumnos sobre la utilidad y las dificultades de la propuesta a nivel de adquisición de destrezas argumentativas, desarrollo de pensamiento crítico y conocimiento bioético. Los resultados muestran que valoran la utilidad de los conocimientos científicos para mejorar la argumentación científica y el pensamiento crítico. Además, destaca la oportunidad de construir sus propios argumentos, integrando los datos con contenido cercano a su realidad. Al mismo tiempo, señalan las dificultades encontradas para identificar los datos relevantes a partir de distintas fuentes de información y seleccionar las pruebas adecuadas para respaldar sus decisiones.
A latent class analysis of multiple health-risk behaviours among Portuguese college students
Authors: Alves Regina
Published: July 2024

Traditionally, the prevalence of health-risk behaviours is high among university students. Although these behaviours are often analysed in isolation, there is likely evidence for the co-occurrence of multiple risk behaviours. In this study, a latent class analysis (LCA) was conducted with cross-sectional data from 840 Portuguese students (55.4% female) to explore patterns of multiple risk behaviours across seven behavioural dimensions (alcohol consumption, smoking, unhealthy eating, sedentary behaviour, risky sexual practices, illicit drug use, and self-medication). Additionally, a latent class regression was performed to explore predictors (perceived well-being and sociodemographic and academic characteristics) for each behavioural pattern. A three-class model emerged with different probabilities of risk: Low-risk behaviours (51.4%), Moderate-risk behaviors (14.9%), and High-risk behaviours (33.7%). Students with better perceptions of well-being and health were likelier to be in the healthier class. Students in the low- and moderate-risk classes were more likely to be in their first year of study, not in a romantic relationship and to be full-time students. Students who had not changed residence at the beginning of their studies and were female were more likely to be in the healthiest class. This study provides essential strategies for health promotion among university students, offering crucial insights for the design of effective health promotion interventions, especially targeted at specific groups of students with similar patterns of multiple risk behaviours.
Knowledge and engagement in research activities by medical students: challenges and new opportunities - an institutional survey.
Authors: Resende Heloisa , Aragão Júlio , Lopes Guilherme , Souza Rafael , Santos Katia , Moraes Daniely , Guedes Clara , Perez Fernanda , Souza Fabrício , Fagundes Riceli , Utagawa Claudia
Published: July 2024

Objectives: to describe participation and knowledge in research programs by medical students from Oswaldo Aranha University Center (Centro Universitário Fundação Osvaldo Aranha, UNIFOA). Methods: it was applied a survey during 2nd Symposium on Clinical Research - focusing on oncology in the South of the State of Rio de Janeiro. The survey was answered by medical students from UNIFOA, encompassing socio-demographic variables, and clinical issues. Results: 73 participants answered the survey, 64.4% (47/73) of them registered up to 3rd semester. Regarding participation in academic research project, 79.5% (67/73) didn’t have any participation, more than fifty per cent 56.2% (41/73), tried to participate in a project, but only 23.3% (17/73) got success in this initiative. Concerning general knowledge in clinical research, 80.8% (59/73) affirmed not had any contact with theme up to moment in their graduation course. Questions evaluating knowledge in basic concepts, described that only 50.7% (37/73) of the students know the difference between basic and clinical research, and only 45.2% (33/73) know the steps of approval process involving medical procedures. Conclusion: low engagement of medical students in research activities might explain the low rate of physicians working on this area. Their potential interest should be enabled by medical schools to increase qualified human resources which will accelerate Brazilian participation in clinical trials.
Medical Mobile Application for The Management of Heart-Lung Machine during Cardiac Surgery
Authors: Demeekul Kanokwan , Boonchai Prarinya , Manin Anuchit , Juncome Arthit , Niangkanta Nanthaphoom , Bunkhampha Kreangkrai , Poomvanicha Montatip , Wongvichit Yonthida , Singkhwa Saranya , Rodmay Sanruethai , Chotimol Phatiwat
Published: July 2024

The goal of this work is to construct a mobile application device that has a wide variety of functions which has clinical planning and decision making for heart-lung machine controlling and to assess the users’ level of satisfaction. The app was constructed according to the steps of design, algorithm, and validation, which is based on the ionic framework. The levels of satisfaction with the developed mobile app among 20 perfusionists were assessed by a questionnaire. The project researchers have officially assigned this medical mobile application with the name is Perfusion Assistant app. that can be accessed and used effectively cross platform on iOS and Android. The application is comprised of 5 main categories which includes: a perfusion calculator, myocardial protection chart, drugs details, priming solution, and parameters values. This finding shown that all cardiovascular parameters did not significant differ from Perfusion Assistant app. when compared to manual calculation. User’s satisfaction was at 3.64 ± 0.76 in the first evaluation. After modification with feedback from experts, the satisfaction of this application was evaluated with a 4.13 ± 0.56. Thereby, Perfusion Assistant app. is an application designed in clinical planning and decision of heart-lung machine controlling for perfusionists and medical staff that work in an opened heart surgery arena. Perfusion Assistant app. offers a variety of calculations related to cardiopulmonary bypass including blood flow rate, systemic vascular resistant, priming volume, and predicted hematocrit. Furthermore, Perfusion Assistant app. provides a quick, easy access, and real-time application for cardiopulmonary bypass that user’s satisfaction was a good level.
Setting Radiation Protection Standards: The First Radiology Congress in 1925
Authors: Rentetzi Maria , Nielsen Aske
Published: July 2024

In 1925, the first International Congress of Radiology took place in London. This Congress brought together almost 500 experts from across the world. For many of the oversees participants, this was a long, difficult, and expensive journey, but the effort paid off. Concerned over the dangers of medical treatment with radium and x-rays, especially for the medical doctors administrating it, and the lack of proper standardization, the Congress gathered to solve these pressing issues. The international and scientific environment of the Congress promised that these issues could be solved, and that an international radiation standard would be settled upon. However, in the international and scientific arena of the Congress, many of the originators of radiation research like Maria Curie and the Vienne Radium Institute were left out, as new scientific centres came to prominence.
Perspectives on Applying Organizational Psychology to Improve Rural Oncology Care
Authors: Kueny Clair
Published: July 2024

This editorial provides an interdisciplinary look at rural oncology care, blending healthcare delivery research, public health literature related to rural healthcare, and organizational science to better understand the benefits and challenges associated with rural cancer care. In particular, I provide a brief overview of how organizational psychology can and should be leveraged to better support rural oncology, including rural cancer centers, rural oncology teams, and individual healthcare professionals that practice in rural settings. This continued convergence of disciplines will further enhance oncology care provision for patients, improve rural healthcare professionals’ work experience, and provide sustainable practices for rural cancer care centers. Recommendations, specifically from the lens of organizational psychology, blended with expertise in rural healthcare, are provided to help researchers, leaders, and healthcare professionals continue to move forward with exemplary rural healthcare.
Mediating Role of Mentalization in Depressive Symptoms Among College University Students
Authors: Solervicens Paula , Kneer Javier , Cerda Kelly , Geldres Andrea , Guzmán Thania
Published: July 2024

This study explores the mediating role of mentalization—the psychological capacity to understand the mental states of oneself and others—in the relationship between academic stress and depressive symptoms among university students during the COVID-19 pandemic. Conducted in Valparaíso, Chile, with a sample of 300 students, the study utilizes a cross-sectional design. Depressive symptoms were assessed using the Patient Health Questionnaire-9 (PHQ-9), stress levels were measured with the Depression Anxiety Stress Scales-21 (DASS-21), and mentalization was evaluated through the Reflective Functioning Questionnaire. Results reveal that disruptions in mentalization, specifically uncertainty about mental states, partially mediate the impact of stress on depressive symptoms, highlighting the crucial role of mentalization processes in the development and management of depressive symptoms under stressful conditions. The findings emphasize the importance of enhancing mentalization capabilities in university settings to improve students' resilience to stress, particularly in crisis situations like the pandemic. This research underscores the necessity of integrating mentalization-focused strategies in preventive and therapeutic interventions for university students to support their mental health and well-being.
Influence of Parenting Patterns and Self-Efficacy on the Leadership of Cadet Regiment at Merchant Marine Polytechnic of West Sumatera
Authors: Irwan Irwan , Putra Riki Wanda , Erlinda Nelfi , Andini Nisye Frisca
Published: July 2024

This research was conducted due to the problem of cadets’ leadership, which is still not perfect. The cadets’ leadership is assumed to be influenced by parenting patterns from the institution and their self-efficacy. This research aims to describe the influence of parenting patterns and self-efficacy on the leadership of cadet regiment. This quantitative research applied ex post facto methods. The population was the cadets of batch VII and VIII at Merchant Marine Polytechnic of West Sumatera. Accordingly, the research sample used a probability sampling technique w ith proportionate stratified random sampling by using the Slovin formula. The total sample of this research was 191 cadets, while the instrumentation was a questionnaire about parenting patterns, self-efficacy, and leadership. The data collection technique was giving a questionnaire directly to the sample. The data analysis technique used multiple linear regression analysis by using the SPSS application. The results showed that Hypotheses 1, 2, and 3 were accepted, which means parenting patterns and self-efficacy influenced the leadership of cadet regiment, and there is an influence of self-efficacy and parenting patterns simultaneously on the leadership of cadet regiment. The relevant practical implication from this research focused on both internal stakeholders, namely the lecturers or officers and the cadets of Merchant Marine Polytechnic of West Sumatera. Therefore, it is recommended that the director and management pay attention to the parenting patterns and the cadets pay attention to their self-efficacy in order to develop better leadership of the cadet regiment.
The Impact of Folklore-Based Storytelling on Empathy Behavior in Kindergarten Children
Authors: Putri Sekaringsih Angrenggani Cahyanti , Ayriza Yulia , Khumalo Jan , Joitun Feuna Anasius
Published: July 2024

The purpose of this study is to understand the impact of using folklore as a storytelling method on the empathy behavior of children in Group B kindergarten. The study uses quantitative methods, specifically the Non-Equivalent Control Group Design technique, involving Group B Harapan Gandok Bopkri Kricak Kindergarten. The sample consists each of 10 childrens in the experimental group and in the control group, selected using total sampling strategy. This study analyzed the data on behavioral empathy gathered through observation using the Wilcoxon Mann-Whitney tests. The results showed that the pretest score for the experimental class was 15,50. After the treatment, the score increased to 28,70. In comparison, the control class had a pretest score of 16.10 and a posttest score of 16,90. The Wilcoxon test yielded a score of Asymp.Sig (2-tailed) = 0.005. The hypotheses test conducted resulted in a significant score of 0.005, which means that Ho is rejected (p 0.05). This study's conclusion can help other schools helped the problems that students going through.
Zasada modelowania a conditio humana wychowanka
Authors: Siewiora Jacek
Published: July 2024

Proces wychowania to szczególne spotkanie wychowawcy i wychowanka, którego – zdaniem W. Okonia – „celem jest wywoływanie zamierzonych zmian w osobowości wychowanka”. Jest to proces złożony, a jego wyniki kształtują się pod wpływem wielu czynników: świadomego i celowego oddziaływania odpowiedzialnych za wychowanie osób i instytucji, odpowiednio zorganizowanego sytemu wychowania oraz wysiłków jednostki nad kształtowaniem własnej osobowości. Niniejszy artykuł poświęcony jest zagadnieniu wychowania przez modelowanie, czyli metodę przykładu. Zasady, rozumiane jako normy postępowania, stosowane są w celu osiągnięcia efektywności podjętego działania. Skoro przyjmujemy konieczność aktywności wychowawcy i wychowanka w ramach realizacji procesu wychowania, to właśnie wykorzystanie z modelowania jawi się jako szczególnie przydatne. Istota modelowania polega bowiem na uruchomieniu mechanizmu identyfikacji wychowanków z określonym modelem, którym może być wychowawca, pozytywny bohater powieści, programu telewizyjnego czy sztuki teatralnej. Można odnieść wrażenie, że modelowanie zwłaszcza poprzez dawanie przez wychowawcę osobistego przykładu jako istotny czynnik oddziaływania wychowawczego zostało nieco zapomniane. W artykule przypomniano zatem ideę przykładu w procesie wychowania, zagadnienie kształtowania sumienia pedagoga i zasadność samooceny.
Solitary deformation waves in two coaxial shells made of material with combined nonlinearity and forming the walls of annular and circular cross-section channels filled with viscous fluid
Authors: Mogilevich Lev ,   Yuri Gagarin State Technical University of Saratov, Blinkov Yuri , Popova Elizaveta , Popov Victor ,   Saratov State University,   Yuri Gagarin State Technical University of Saratov,   Yuri Gagarin State Technical University of Saratov
Published: July 2024

The aim of the paper is to obtain a system of nonlinear evolution equations for two coaxial cylindrical shells containing viscous fluid between them and in the inner shell, as well as numerical modeling of the propagation processes for nonlinear solitary longitudinal strain waves in these shells. The case when the stress-strain coupling law for the shell material has a hardening combined nonlinearity in the form of a function with fractional exponent and a quadratic function is considered. Methods. To formulate the problem of shell hydroelasticity, the Lagrangian–Eulerian approach for recording the equations of dynamics and boundary conditions is used. The multiscale perturbation method is applied to analyze the formulated problem. As a result of asymptotic analysis, a system of two evolution equations, which are generalized Schamel– Korteweg– de Vries equations, is obtained, and it is shown that, in general, the system requires numerical investigation. The new difference scheme obtained using the Grobner basis technique is proposed to discretize the system of evolution equations. Results. The exact solution of the system of evolution equations for the special case of no fluid in the inner shell is found. Numerical modeling has shown that in the absence of fluid in the inner shell, the solitary deformation waves have supersonic velocity. In addition, for the above case, it was found that the strain waves in the shells retain their velocity and amplitude after interaction, i.e., they are solitons. On the other hand, calculations have shown that in the presence of a viscous fluid in the inner shell, attenuation of strain solitons is observed, and their propagation velocity becomes subsonic.
Global synchronization in lattices of chaotic maps with limited number of connections
Authors: Andreyev Yury ,   Moscow Institute of Physics and Technology
Published: July 2024

Stability of the global synchronous mode of chaotic map lattices is investigated by means of direct calculation of the stability conditions, and by means of numerical simulation. The lattices with local connections are shown to have a limit value of the Lyapunov exponent of the lattice maps, above which the global synchronous mode loses stability. The synchronous mode in large lattices is found impossible due to the local nature, i.e., «short range» of the connections. We propose some approaches to modification of the dynamic system structure that can provide stability of the synchronous mode, such as tuning the dynamic mode of the lattice maps, extension of the local neighborhood, use of nonlocal static and dynamic connections, and introduction of an external control node (a pacemaker). In the model with the pacemaker, a spatial synchronous lattice mode is revealed, different from the pacemaker mode («generalized» synchronization).