In vivo application of poly-3-hydroxyoctanoate as peripheral nerve graft     

D. Burcu Hazer  Ercan Bal  Gülay Nurlu  Kemal Benli  Serdar Balci  Feral Öztürk  Baki Hazer 《Journal of Zhejiang University. Science. B》2013,14(11):993-1003

Objective

This study aims to investigate the degree of biocompatibility and neuroregeneration of a polymer tube, poly-3-hydroxyoctanoate (PHO) in nerve gap repair.

Methods

Forty Wistar Albino male rats were randomized into two groups: autologous nerve gap repair group and PHO tube repair group. In each group, a 10-mm right sciatic nerve defect was created and reconstructed accordingly. Neuroregeneration was studied by sciatic function index (SFI), electromyography, and immunohistochemical studies on Days 7, 21, 45 and 60 of implantation. Biocompatibility was analyzed by the capsule formation around the conduit. Biodegradation was analyzed by the molecular weight loss in vivo.

Results

Electrophysiological and histomorphometric assessments demonstrated neuroregeneration in both groups over time. In the experimental group, a straight alignment of the Schwann cells parallel to the axons was detected. However, autologous nerve graft seems to have a superior neuroregeneration compared to PHO grafts. Minor biodegradation was observed in PHO conduit at the end of 60 d.

Conclusions

Although neuroregeneration is detected in PHO grafts with minor degradation in 60 d, autologous nerve graft is found to be superior in axonal regeneration compared to PHO nerve tube grafts. PHO conduits were found to create minor inflammatory reaction in vivo, resulting in good soft tissue response.  相似文献   

Use of technology-assisted techniques of mind mapping and concept mapping in science education: a constructivist study     

Ali Günay Balım 《Irish Educational Studies》2013,32(4):437-456

The study aims to investigate the effects of using mind maps and concept maps on students' learning of concepts in science courses. A total of 51 students participated in this study which used a quasi-experimental research design with pre-test/post-test control groups. The constructivist-inspired study was carried out in the sixth-grade science course unit of ‘Light and Sound’ in a primary school with two experimental groups and one control group. The intervention was held in the experimental group 1 by using technology-assisted technique of mind mapping, in the experimental group 2 by using technology-assisted technique of concept mapping, and in the control group by means of traditional classroom instruction. After the intervention in the experimental groups, concept tests and open-ended questions related to the unit were used as post-tests. According to the data obtained from concept tests, it was found out that all groups' understanding of concepts was equivalent. Significantly, students in the experimental group 2 reported positive opinions, stating that learning through concept maps was useful and engaging.  相似文献   

Symptomatology in adolescents following initial disclosure of sexual abuse: The roles of crisis support, appraisals and coping     

Sarah Bal  Geert Crombez  Ilse De Bourdeaudhuij  Paulette Van Oost 《Child abuse & neglect》2009,33(10):717-727

ObjectiveThe present study examined possible explanations for symptom development and variability in sexually abused adolescents. A theoretical model of sexual abuse, in which appraisal, coping and crisis support play prominent roles, was tested in a clinical group of 100 sexually abused adolescents.MethodParticipants, aged 12–18 years, completed questionnaires regarding severity of abuse, negative appraisals, crisis support, coping strategies, and trauma-related stress symptoms.ResultsSince severity of abuse had no influence on the association between appraisals and symptoms it was eliminated from our model. Structural equation modeling analyses showed a significant interrelationship between the examined concepts. Adolescents who appraised the abuse as more threatening showed more internalizing and externalizing trauma symptoms. Moreover, more negative appraisals were associated with more avoidance as well as with more active coping strategies. Direct crisis support was associated with less negative appraisals and with the use of more active coping strategies.ConclusionsThe study showed that especially the buffering role of crisis support and the role of negative appraisals explained symptom development and variety in sexually abused adolescents.Practice implicationsAdaptation to sexual abuse includes the ways in which adolescents perceive the event as threatening and harmful, how they cope with the abusive experience, and how they receive direct support from their family. Clinicians, therefore, need to expand the focus of their assessments beyond age- and trauma-specific symptoms, to age- and trauma-specific appraisals, coping, and social support. The assessment of these factors should take place as soon as possible after the disclosure of the abuse. Individualized treatment plans and clinical interventions need to be based on these personal and environmental variables, rather than reliance on the influence of abuse-related characteristics, such as the severity or type of abuse.  相似文献   

Paradigm wars, dialogue or dance: is rapprochement possible and/or desirable?     

Bal Chandra Luitel  Elisabeth Settelmaier  Les Pereira  Paula Joyce  Emilia Nhalevilo  Alberto Cupane  Peter Charles Taylor 《Cultural Studies of Science Education》2009,4(3):529-552

In focusing on the Kincheloe and Tobin paper, ‘The Much Exaggerated Death of Positivism,’ this forum explores the hegemony of positivism in the professional practices of a group of educators whose research expertise lies in the fields of science education, mathematics education and leadership education. Responding to the first question, ‘What is your personal/professional experience of the hegemony of positivism?’, four key issues arise: is positivism part of the external world or is it within us (and thus what is our agency)?, the role of positivism as a driver of Western cultural imperialism, dualism as the chief logic of positivism, and the difficulty of responding to positivism from a pluralist perspective. The second question, ‘Is rapprochement between positivism and other paradigms possible and/or desirable without being re-colonised?’, raises a number of key issues that, although relatively new to science education, are of increasing interest to cultural studies researchers keen to embrace alternative research paradigms with which to create culturally inclusive science curricula. The discussants reveal their personal experiences of being marginalised by the hegemony of positivism and give voice to a range of opinions about how best to respond. The integral perspective of spiral dynamics is proposed as a model of paradigm evolution, our fundamental assumptions about modern progress are questioned, and the non-dualist logic of dialectics is explored as a more inclusive rationality for researchers. In the spirit of counter-hegemonic cultural studies, the discussants draw on their personal Buddhist and Hindu perspectives to open new doorways into complex ontological systems lying beyond the simplistic materialism of crypto-positivism. We are given a glimpse of powerful means of generating new insights into the emergent universe (within and without) that an evolving science endeavours to explain.  相似文献   

Social problem-solving among disadvantaged and non-disadvantaged adolescents     

László Kasik  Fejes József Balázs  Kornél Guti  Csaba Gáspár  Anikó Zsolnai 《欧洲特需教育杂志》2018,33(1):86-101

The study examined the differences of social problem-solving (SPS) among 12-, 14- and 16-year-old Hungarian disadvantaged and non-disadvantaged adolescents (N = 382) and investigated the relationship between SPS and family background (FB). SPS was measured through students’ own and their teachers’ evaluations by an adapted questionnaire (Social Problem-Solving Inventory–Revised, factors: negative/positive problem orientation, rationality, impulsivity and avoidance). Based on the total values of SPS, the difference between disadvantaged and non-disadvantaged adolescents was significant in all age groups in the case of negative orientation. The difference was significant in the case of impulsivity at the age of 12; in the case of avoidance at the age of 14; in the case of rationality and avoidance at the age of 16. FB had the strongest link with negative orientation, impulsivity and avoidance. In case of impulsivity and avoidance, variance explained by FB was higher among 16-year olds than among 12- and 14-year olds.  相似文献   

Role of Oncofetal Protein CR-1 as a Potential Tumor Marker for Oral Squamous Cell Carcinoma     

Anu Jain  Sumanth Kumar Mallupattu  Reetu Thakur  Satyawati Mohindra  Amanjit Bal  Ashim Das  Sushmita Ghoshal  Arnab Pal 《Indian journal of clinical biochemistry : IJCB》2021,36(3):288

Cripto-1 (CR-1) is an oncofetal protein with its role as a key factor in early process of carcinoma has been evaluated in cases of various cancers. However, very few studies have reported its role in oral cancer, which is the sixth most common cancer around the world, particularly with high prevalence in developing countries. Oral squamous cell carcinoma (OSCC) is the most predominant (90%) of all the histological types of oral cancer. Late detection, associated with increased morbidity and mortality, is mainly attributed to non-availability of a suitable biomarker for the disease. In the present pilot study, we have evaluated the role of soluble CR-1, in serum as a potential tumor marker for OSCC. CR-1 was estimated using sandwich ELISA in serum samples of 50 biopsy proven OSCC patients (pre and post treatment) along with age and gender matched healthy controls. Immunohistochemistry was also done in corresponding tumor tissue sections to check the expression of CR-1. Pre-treatment CR-1 was found to be 2.25-fold higher in serum of OSCC patients as compared to control (p < 0.0001***), which was reduced to 1.6 folds post treatment (p = 0.0006***). CR-1 levels were comparatively higher in early stage of disease. Upon IHC 80% of the cases were found to be positive for CR-1. This study provides evidence that serum levels of CR-1 are elevated in patients of Oral Squamous Cell Carcinoma, which decrease post treatment. Also, the association of expression of protein with tumor progression predicts CR-1 as a molecule that can be further evaluated as a potential tumor maker in OSCC.  相似文献   

Ranking institutions within a discipline: The steep mountain of academic excellence     

Balázs R. Sziklai 《Journal of Informetrics》2021,15(2):101133

We present a novel algorithm to rank smaller academic entities such as university departments or research groups within a research discipline. The Weighted Top Candidate (WTC) algorithm is a generalisation of an expert identification method. The axiomatic characterisation of WTC shows why it is especially suitable for scientometric purposes. The key axiom is stability – the selected institutions support each other's membership. The WTC algorithm, upon receiving an institution citation matrix, produces a list of institutions that can be deemed experts of the field. With a parameter we can adjust how exclusive our list should be. By completely relaxing the parameter, we obtain the largest stable set – academic entities that can qualify as experts under the mildest conditions. With a strict setup, we obtain a short list of the absolute elite. We demonstrate the algorithm on a citation database compiled from game theoretic literature published between 2008–2017. By plotting the size of the stable sets with respect to exclusiveness, we can obtain an overview of the competitiveness of the field. The diagram hints at how difficult it is for an institution to improve its position.  相似文献   

Electroencephalogram and Heart Rate Regulation to Familiar and Unfamiliar People in Children With Autism Spectrum Disorders     

Amy Vaughan Van Hecke  Jocelyn Lebow  Elgiz Bal  Damon Lamb  Emily Harden  Alexis Kramer  John Denver  Olga Bazhenova  Stephen W. Porges 《Child development》2009,80(4):1118-1133

Few studies have examined whether familiarity of partner affects social responses in children with autism. This study investigated heart rate regulation (respiratory sinus arrhythmia [RSA]: The myelinated vagus nerve's regulation of heart rate) and temporal–parietal electroencephalogram (EEG) activity while nineteen 8- to 12-year-old children with autism and 14 controls viewed videos of a familiar and an unfamiliar person reading a story. Children with autism had lower overall RSA levels and exhibited decreased RSA to the unfamiliar person, versus control children. Both groups decreased temporal–parietal EEG activity to the unfamiliar person. Higher RSA was related to higher social skill ratings and fewer problem behaviors. Thus, the social difficulties of children with autism may be characterized by specific mobilization to unfamiliar people.  相似文献   

Neural Differences in Bilingual Children's Arithmetic Processing Depending on Language of Instruction     

Katrien Mondt  Esli Struys  Maurits Van den Noort  Danielle Balériaux  Thierry Metens  Philippe Paquier  Piet Van de Craen  Peggy Bosch  Vincent Denolin 《Mind, Brain, and Education》2011,5(2):79-88

Many children in bilingual regions follow lessons in a language at school (school‐language) that they hardly ever speak at home or in other informal settings. What are the neural effects of this phenomenon? This functional magnetic resonance imaging (fMRI) study investigates the effects of using school‐language on brain activity during a high cognitive task in two groups of French/Dutch bilingual children. Participants were asked to assess the correctness of 3‐operand (e.g., 5 ? 2 = 3) and 4‐operand (e.g., 3 ? 2 = 1 + 4) equations, respectively. Instructions about the task were given either in the children's school‐language or in another language that they only used at home. It was found that although both groups recruited a visuomotor occipitofrontal network in the left hemisphere, the children who performed the task in their school‐language showed less activation than the children who did not, indicating the importance of language of instruction for bilingual children's arithmetic processing.  相似文献   

The effect of potential fall distance on hormonal response in rock climbing     

Jiří Baláš  David Giles  Leona Chrastinová  Kateřina Kárníková  Jan Kodejška  Alžběta Hlaváčková 《Journal of sports sciences》2017,35(10):989-994

The aim of this study was to examine the effect of alterations in potential lead fall distance on the hormonal responses of rock climbers. Nine advanced female climbers completed two routes while clipping all (PRO-all) or half (PRO-½) of the fixed points of protection. Venous blood samples were analysed for total catecholamines, noradrenaline (norepinephrine), adrenaline (epinephrine), dopamine, lactate, cortisol and serotonin. Differences between the two conditions pre, immediately post and 15 min post climbing were assessed using a 2 × 3 repeated measures ANOVA. All hormones and blood lactate concentrations increased significantly (P < 0.05) immediately post climb, except for cortisol. Peak cortisol concentrations did not occur until 15 min post ascent. Further, significant interactions between climbing and clipping conditions were found for total catecholamines (890% of basal concentration in PRO-½ vs. 568% in PRO-all), noradrenaline (794% vs. 532%) and dopamine (500% vs. 210%). There were no significant interactions for adrenaline (1920% vs. 1045%), serotonin (150% vs. 127%) or lactate (329% vs. 279%). The study showed a greater catecholamine response with an increase in potential lead fall distance. The most pronounced increases seen in catecholamine concentration were reported for dopamine and noradrenaline.  相似文献