462 research outputs found
Implicit Theories and Self-efficacy in an Introductory Programming Course
Contribution: This study examined student effort and performance in an
introductory programming course with respect to student-held implicit theories
and self-efficacy. Background: Implicit theories and self-efficacy shed a light
into understanding academic success, which must be considered when developing
effective learning strategies for programming. Research Questions: Are implicit
theories of intelligence and programming, and programming-efficacy related to
each other and student success in programming? Is it possible to predict
student course performance using a subset of these constructs? Methodology: Two
consecutive surveys (N=100 and N=81) were administered to non-CS engineering
students in I\c{s}{\i}k University. Findings: Implicit theories and
self-beliefs are interrelated and correlated with effort, performance, and
previous failures in the course and students explain failure in programming
course with "programming-aptitude is fixed" theory, and also that programming
is a difficult task for themselves.Comment: Programming Education. 8 page
Effects of alloplastic graft material combined with a topical ozone application on calvarial bone defects in rats
Background: This study presents the evaluation of the damage in the bone tissue resulting from a calvarial defect in rats and the efficiency of exposure to an ozone application with an alloplastic bone graft on the calvarial bone damage.
Materials and methods: Wistar male rats (n = 56) were divided into four groups: a control group (n = 14), defect and ozone group (n = 14), defect and graft group (n = 14), and defect, graft, and ozone group (n = 14). Under anaesthesia, a circular full-thickness bone defect was created in all groups, and the experimental groups were further divided into two sub-groups, with 7 rats in each group sacrificed at the end of the 4th and 8th weeks. Bone samples were dissected, fixed in 10% formalin solution, and decalcified with 5% ethylene-diamine-tetraacetic acid (EDTA). After the routine follow-up on tissues, immunostaining of osteopontin and osteonectin antibodies was applied to sections and observed under a light microscope.
Results: The control group exhibited osteopontin and osteonectin expression in fibroblasts and inflammatory cells at the end of the 4th week with an acceleration at the 8th week. Ozone administration elucidated new trabecular bone formation by increasing osteoblastic activity. Lastly, our observations underscore that a combination of allograft and ozone application increased the osteoblast, osteocyte, and bone matrix development at the 4th and 8th weeks.
Conclusions: Exposure to an ozone application with an alloplastic bone graft on calvarial bone damage may induce osteoblastic activity, matrix development, mature bone cell formation, and new bone formation in rats
Effects of formaldehyde on vascular endothelial growth factor, matrix metallopeptidase 2 and osteonectin levels in periodontal membrane and alveolar bone in rats
Background: The objective of this study was to investigate whether long term formaldehyde inhalation may affect periodontal membrane and alveolar bone loss leading to periodontitis. The negative effects of formaldehyde were described using vascular endothelial growth factor (VEGF), matrix metallopeptidase 2 (MMP-2) and osteonectin antibodies involved in the extracellular matrix and angiogenetic development.
Materials and methods: Thirty adult Wistar albino rats were used in this study. Rats were divided into two groups: a control group (n = 15) and formaldehyde administered group (n = 15). Formaldehyde group was exposed to inhalation of 10 ppm formaldehyde 8 hours a day, 5 days a week for 5 weeks. Maxillary bone regions were dissected under anaesthesia. After fixation in 10% formaldehyde solution, tissues were passed through graded ethanol series to obtain paraffin blocks. Five-micrometre histological sections were cut with RM2265 rotary microtome stained with Masson trichrome and VEGF, MMP-2 and osteonectin antibodies for examination under Olympus BH-2 light microscopy.
Results: The present study revealed that congestion in blood vessels, degeneration of collagen fibres and alveolar matrix around alveolar bone were observed to be more significant in formaldehyde group than the control group (p ≤ 0.001). Interestingly, VEGF expression in the formaldehyde group was the most significant finding between the two groups (p < 0.001). When compared inflammation, MMP-2 and osteonectin expressions were significant (p < 0.01) in the formaldehyde group.
Conclusions: It was suggested that formaldehyde toxicity decreased the expression of MMP-2 and in osteoblasts as well as affecting the retention of MMP levels in tooth cavity, which is very low in collagen fibres. But, vice versa for the expression of VEGF in dilated vascular endothelial cells and osteocytes in alveolar bone. As a conclusion, formaldehyde disrupts the periodontal membrane and may cause collagen fibres degeneration by affecting the alveolar bone matrix
COVID-19 infection, vaccine status, and avoidance behaviors in adults with attention deficit and hyperactivity disorder: A cross-sectional study
ObjectiveWe aim to examine infection risk and vaccine status of COVID-19 in attention deficit and hyperactivity disorder and evaluate the impact of demographic, clinical, and COVID-19-related factors on the infection status and behavioral avoidance of COVID-19. MethodsThis cross-sectional study assessed adults with attention deficit and hyperactivity disorder recruited from an outpatient psychiatry clinic. Patients and healthy controls completed a survey on sociodemographic data, COVID-19 infection status, and vaccine status. COVID-19 Disease Perception Scale, COVID-19 Avoidance Attitudes Scale, Attitudes toward COVID-19 Vaccine Scale, Adult Attention Deficit and Hyperactivity Disorder Self-report Screening Scale for DSM-5, Adult Attention Deficit and Hyperactivity Disorder Self-Report Scale Symptoms Checklist, Patient Health Questionnaire-9, and State-Trait Anxiety Inventory were applied. ResultsNinety patients and 40 healthy controls participated. Patients did not differ from controls in COVID-19 infection and vaccine status, and behavioral avoidance of COVID-19. No demographic and clinical factor significantly affected the COVID-19 infection status. Patients scored higher than controls in the perception of COVID-19 as contagious (p = 0.038), cognitive avoidance of COVID-19 (p = 0.008), and positive attitudes toward the COVID-19 vaccine (p = 0.024). After adjustment of possible factors, a positive perception of the COVID-19 vaccine and a perception of COVID-19 as dangerous were the two factors significantly affecting behavioral avoidance of COVID-19 [R-2 = 0. 17, F(2) = 13.189, p < 0.0001]. ConclusionInfection and vaccine status of COVID-19 in patients did not significantly differ from controls. No demographic and clinical factor significantly affected the COVID-19 infection status. Approximately four-fifths of the patients were fully vaccinated as recommended by national and global health organizations. This has increased the knowledge base showing that the COVID-19 vaccine is acceptable and receiving the vaccine is endorsed by ADHD patients. Attention deficit and hyperactivity disorder itself may provoke no kind of mental disturbance in sense of perception of the danger of this disease. Our findings have increased the knowledge base showing that the COVID-19 vaccine is acceptable and the actual practice of receiving the vaccine is endorsed in this population. Our message for practice would be to take into account not only the core symptoms and the comorbidities of the disorder but also the perception of the disease while exploring its link with COVID-19
A content-linking-context model for “notice-and-takedown” procedures
The US Digital Millennium Copyright Act (DMCA) of 1998 adopted a notice-and-take-down procedure to help tackle alleged online infringements through online service providers’ actions. The European Directive 2000/31/EC (e-Commerce Directive) introduced similar liability exemptions, but did not specify any take-down procedure. Many intermediary (host, and online search engine) service providers even in Europe have followed this notice-and-take-down procedure to enable copyright owners to issue notices to take down allegedly infringing Web resources. However, the accuracy of take-down is not known, and notice receivers do not reveal clear information about how they check the legitimacy of these requests, about whether and how they check the lawfulness of allegedly infringing content, or what criteria they use for these actions. In this paper, we use Google’s Transparency Report as the benchmark to investigate the information content of take-down notices and the accuracy of the resulting take-downs of allegedly infringing Web resources. The analysis of copyright infringement is limited to the five scenarios most frequently encountered in our study of Web resources. Based on our investigation, we propose a Content-Linking-Context (CLC) model of the criteria to be considered by intermediary service providers to achieve more accurate take-down
Logistic autonomous vehicles assessment using decision support model under spherical fuzzy set integrated Choquet Integral approach
Autonomous vehicles (AVs) are the newest products in the intelligent transportation system that can move around with minimal human intervention. These products continue their path with all kinds of sensors with different parts. Effective use of these technologies in the logistics industry can create a competitive advantage. Nowadays, there are many AVs, some of which are superior to others in terms of build quality, variety of features, and design. Choosing an efficient, optimal, and reliable vehicle is one of the most important challenges in logistics planning. Therefore, choosing an AV based on a series of criteria can be considered a multi-criteria decision-making (MCDM) problem. Due to the complication of decision-making issues, criteria are usually not independent of each other and there are relationships between them. Therefore, this study develop an extended MCDM framework based on Choquet integral (CI) under group decision-making with a Spherical fuzzy set (SFS) for assessing logistics AVs. The CI technique is expanded with SFS to increase the power of CI. Furthermore, the combination of CI with SFS leads to greater freedom for decision makers to express opinions and use three independent membership functions. Accordingly, the interactions between the criteria are considered and the skepticism and uncertainty present during the decision are controlled. The proposed approach is implemented in selecting the best AVs in the logistics industry, and the results are compared with Pythagorean fuzzy CI and Intuitionistic fuzzy CI. Moreover, sensitivity analysis is done by changing the weights and creating different scenarios to confirm and check the robustness of the proposed approach results. The results indicate the suggested approach's efficiency and the ranking's stability in different scenarios
Metastasis of breast carcinoma to the external auditory canal: Report of an unusual case and literature review
We present a case of metastasis of the external auditory canal (EAC) from a primary breast carcinoma in a 53-year-old female with a review of the literature. The patient had been diagnosed with a primary carcinoma 4 years previously. The metastasis had developed recently in her left EAC and presented as a bulky, fleshy, bleeding mass. The mass was causing hearing loss on the left due to complete obstruction in the left EAC. The mass was incompletely removed with a surgical operation and histopathologically metastasis was proven. Although there are few case reports in the literature of various cancers metastasizing to the EAC, metastasis in the EAC from the breast carcinoma is exceedingly rare and only one case has been reported in the literature so far
Electromagnetic interference shielding performance of carbon nanostructure reinforced, 3D printed polymer composites
We report the electrical, mechanical and electromagnetic interference (EMI) shielding performance of polypropylene random copolymer (PPR)/multi-wall carbon nanotube (MWCNT) nanocomposites enabled via customized fused filament fabrication process. The electro-conductive PPR/MWCNT filament feedstocks were fabricated via shear-induced melt-blending process that allows 3D printing of nanoengineered composites even at higher MWCNT loading (up to 8 wt%). The uniform dispersion of MWCNTs in PPR matrix confirmed via Raman spectroscopy and scanning electron microscopy facilitates better mechanical, electrical and EMI shielding performance. The results furthermore show enhanced shielding properties and higher attenuation for the nanocomposites printed in 90° direction (~ − 37 dB for 8 wt% MWCNT loading). Effective interfacial adhesion between the beads with lesser extent of voids (confirmed via micro-computed tomography) endorsed low transmission loss in nanocomposites printed in 90° direction compared to samples printed in 0° direction. Surface architected structure (frustum shape) reveals higher specific shielding effectiveness (maximum ~ − 40 dBg−1cm3, + 38%) over the plain structure. The realization of excellent shielding effectiveness (~ 99.9% attenuation) of additive manufacturing-enabled PPR/MWCNT nanocomposites demonstrates their potential for lightweight and strong EMI shields
Integrated method for quantitative morphometry and oxygen transport modelling in striated muscle
Identifying structural limitations in O2 transport is primarily restricted by current methods employed to characterise the nature of physiological remodelling. Inadequate resolution or breadth of available data has impaired development of routine diagnostic protocols and effective therapeutic strategies. Understanding O2 transport within striated muscle faces major challenges, most notably in quantifying how well individual fibres are supplied by the microcirculation, which has necessitated exploring tissue O2 supply using theoretical modelling of diffusive exchange. Having identified capillary domains as a suitable model for the description of local O2 supply, and requiring less computation than numerically calculating the trapping regions that are supplied by each capillary via biophysical transport models, we sought to design a high throughput method for histological analysis. We present an integrated package that identifies optimal protocols for identification of important input elements, processing of digitised images with semi-automated routines, and incorporation of these data into a mathematical modelling framework with computed output visualised as the tissue partial pressure of O2 (PO2) distribution across a biopsy sample. Worked examples are provided using muscle samples from experiments involving rats and humans
Aspartame induces angiogenesis in vitro and in vivo models
Angiogenesis is the process of generating new blood vessels from preexisting vessels and is considered essential in many pathological conditions. The purpose of the present study is to evaluate the effect of aspartame on angiogenesis in vivo chick chorioallantoic membrane (CAM) and wound-healing models as well as in vitro 2,3-bis-2H-tetrazolium-5-carboxanilide (XTT) and tube formation assays. In CAM assay, aspartame increased angiogenesis in a concentration-dependent manner. Compared with the control group, aspartame has significantly increased vessel proliferation (p < 0.001). In addition, in vivo rat model of skin wound-healing study showed that aspartame group had better healing than control group, and this was statistically significant at p < 0.05. There was a slight proliferative effect of aspartame on human umbilical vein endothelial cells on XTT assay in vitro, but it was not statistically significant; and there was no antiangiogenic effect of aspartame on tube formation assay in vitro. These results provide evidence that aspartame induces angiogenesis in vitro and in vivo; so regular use may have undesirable effect on susceptible cases. © The Author(s) 2015
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