Mehanička svojstva jednoslojne ploče iverice od drva vrbe (Salix viminalis) u ovisnosti o sadržaju ljepila i gustoći ploče

The paper presents the results of studies on the mechanical properties of one-layer particleboards made from willow (Salix viminalis). Since the particleboards were to simulate the core layer of typical furniture three-layer particleboards, they were made from coarse particles of the size from 1 to 4 mm using urea-formaldehyde resin as a binder. The effects of board density and resin content were evaluated. Three levels of resin content: 8, 9 and 10 %, and board density: 0.57, 0.60 and 0.63 g/cm3, were assumed. The effects of both factors, for their assumed ranges of variation, on the mechanical properties of particleboard were statistically signifi cant. The modulus of elasticity (MOE), modulus of rupture (MOR), internal bond (IB) and screw holding strength (SHS) were determined. The effect of board density on MOE and MOR was greater than that of resin content, whereas the effect of board density on IB and SHS was less than that of resin content.U radu su prikazani rezultati istraživanja mehaničkih svojstava jednoslojne ploče iverice izrađene od drva vrbe (Salix viminalis). Kako bi se dobile iverice koje simuliraju srednji sloj tipične troslojne ploče za izradu namještaja, iverice su izrađene od drvnih čestica veličine od 1 do 4 mm, uz primjenu urea-formaldehidnog ljepila kao veziva. Procijenjen je utjecaj gustoće ploče i sadržaja ljepila na mehanička svojstva ploča. Istražene su tri razine sadržaja ljepila: 8, 9 i 10 %, te tri gustoće ploče: 0,57, 0,60 i 0,63 g/cm3. Utjecaj sadržaja ljepila i gustoće na mehanička svojstva ploča statistički je značajan. Istraživana su ova mehanička svojstva ploča: modul elastičnosti (MOE), modul loma (MOR), unutrašnja čvrstoća vezanja (IB) i čvrstoća držanja vijaka (SHS). Gustoća ploče imala je veći utjecaj na MOE i MOR nego sadržaj ljepila, dok je utjecaj gustoće ploče na IB i SHS bio manji od utjecaja sadržaja ljepila

INFLUENCE OF SELECTED FACTORS ON DEVELOPMENT THE STUDENTS\u27 OF THE BIOLOGICAL SCIENCES FACULTIES BIOETHICAL ATTITUDES TOWARDS EXPERIMENTAL ANIMAL STUDIES

Background: Although it may help to widen our knowledge, conducting experiments with use of animals, is very controversial, especially since the most recent technology enables us to significantly avoid their use. Currently, the European directives require researchers to reduce the using of animals in scientific experiments, but some studies suggest awareness of the problem is still insufficient. Thanks to examining students’ attitude towards conducting scientific experiments on animals the authors wanted to discover and mark the most significant factors that might have impact on moulding students‘ opinions. Subjects and methods: 217 subjects participated in the study. They were students of the Faculty of Medicine at the Silesian Medical University in Katowice and students of the Biology & Biotechnology Faculty at the University of Silesia. A proprietary questionnaire sent via the Internet was used. The authors created specific ratios and numeral 5-grade Likert-type scale showing the behavioural, cognitive and affective component of the respondents’ attitudes on the issue being studied. It contained among other things the questions such as granting animals personality, consciousness, and the right to life. The method used allowed the investigators to show the general trends of all the studied responses and therefore the compilation of results. Results: The study showed that the attitude of respondents on studied subject undergoes some changes related to gender. Furthermore, the results did not depend with statistical significance on previous experience in conducting such experiments, religious belief of respondent, his or her parents type and level of education. It also showed the that students had little knowledge about current animal protection law and alternative methods to animal research. Conclusions: The results show the complexity and multiplicity of factors influencing the attitudes of bioethics and point to the need to deepen our knowledge in the studied area

OCCURENCE OF SLEEP ABNORMALITIES AMONG PEOPLE WITH MENTAL DISORDERS - QUESTIONNAIRE STUDY

Background: Sleep disorders belong to the most common health problems in modern society. The aim of this study was to analyze and determine different factors, which have an impact on the occurrence of sleep abnormalities among people with mental illnesses. Subject and methods: An original questionnaire containing 23 questions was created. 49 respondents from an outpatient psychiatric clinic were recruited to the study. Results: The results indicate that the majority of respondents have the frequency of sleep disturbances more than 3 times per week. In 36% of them the length of sleep was not sufficient enough, and nearly half of the patients reported waking up at night. Sleep disturbances resulted in the appearance of several symptoms (tiredness – 66%, lower motivation and lack of energy – 51%, decreased mood - 45%, attention deficits and memory deterioration – 45%, irritability – 43%). Only 19% of them declare a deterioration of their social and vocational functioning. The majority of patients sleep more than 6 hours, but the patients consider this amount of sleep as not sufficient. The methods to cope with reported sleep problems are: most of respondents (68%) take hypnotics, 4% of respondents drink alcohol before going to sleep, 4% try to solve the problem with sex or masturbation. 9% reported talking about this problem with family member and/or friends. The other 13% of the respondents do not try to make any efforts to manage their sleep disturbances. Conclusion: The questionnaire confirmed that sleep disturbances are common in mental disorders and the problem of insomnia has a negative impact on mood and quality of life for the majority of the patients who we studied

SOCIAL ATTITUDE TOWARDS MENTALLY ILL IN COMPARISON TO EXPERTS’ OPINIONS

Background: In modern psychiatry, deinstitutionalization of mentally ill became an essential part of improving state of being of those affected. Integration in community, despite obvious benefits, led to increase in social distance and rejection towards mentally ill. Social stigma affects different life domains of those afflicted, and therefore it is crucial to introduce methods to deal with it. Our objective was to assess and compare psychiatrists’ and public attitudes and beliefs about mentally ill people. Materials and methods: Comparison of two samples, one including 107 psychiatrists and second including 708 individuals of the general population. Obtained outcomes were collated with similar studies available in literature. Outcomes: The psychiatrists’ attitude was more positive in comparison to the general population. Both groups agree that programs raising public awareness are important, and should be intensified. 41% of general population and 13% of respondents from experts’ group think of negative associations with mentally ill. Conclusions: Conception of utilizing mental health experts as the opinion leaders should be carefully thought through. Although awareness of social distance and stigma improved both among psychiatrists and general population since 2005 (Wciorka & Wciorka 2006, Lauber 2004), still there are areas that needs enhancement. Fear present in both groups, probably caused by inter allia image of mental illness in news reports (Angermeyer 2001), is one of such areas

Systematic Review of Literature on Single-Nucleotide Polymorphisms Within the Oxytocin and Vasopressin Receptor Genes in the Development of Social Cognition Dysfunctions in Individuals Suffering From Autism Spectrum Disorder

Introduction: Autism spectrum disorder (ASD) is found in virtually all population groups regardless of ethnic or socioeconomic backgrounds. Among others, dominant symptoms of autism persistent throughout its course of development include, inter alia, qualitative disorders of social communication and social interactions. Numerous studies have been performed on animal models as well as groups of healthy individuals to assess the potential role of oxytocinergic and vasopresynergic systems in normal social functioning. These studies have also discussed their potential participation in the development of social cognition dysfunctions in the course of ASD. This literature review aimed to identify studies examining single-nucleotide polymorphisms of the oxytocin (OXT) and arginine vasopressin (AVP) receptor genes and their differential effects on social cognitive dysfunction in the development of ASD.Methods: A systematic review of literature published within the last 10 years and accessible in PubMed, Google Scholar, Cochrane Library, and APA PsycNET databases was conducted by each author separately. Inclusion criteria required that articles should 1) be published between January 2008 and August 2018; 2) be published in English or Polish; 3) be located in periodical publications; 4) focus on the role of polymorphisms within oxytocin and vasopressin receptor genes in autistic population; 5) provide a clear presentation of the applied methodology; and 6) apply proper methodology.Results: From the 491 studies qualified to the initial abstract analysis, 15 met the six inclusion criteria and were included in the full-text review.Conclusions: The analysis of available literature seems to indicate that there is an association between social cognition dysfunctions in the course of autism and selected alleles of polymorphisms within the OXT receptor AVP 1A receptor genes. However, previous studies neither specify the nature of this association in an unequivocal way nor select genotypes that are the basis for this association

IMPLEMENTATION OF THE MOTEK CAREN SYSTEM IN BEHAVIOURAL THERAPY FOR PATIENTS WITH ANXIETY DISORDERS

Background: Virtual reality exposure therapy (VRET) is becoming a more and more popular treatment method for patients suffering from anxiety disorders. One of the VRET methods, wchich could be used for this group of patients is MOTEK CAREN system, however, so far no studies have been published on its implementation in psychiatric disorders. Subject and methods: Presented here is a case of a 45 year old woman suffering from anxiety disorders, who underwent a series of four subsequent trainings with the use of MOTEK CAREN system repeted once a week. Data from the system were collected on the work of muscles, joints, reactions of the ground, etc. Blood pressure, pulse and salivary cortisol level were measured before and after each training. The level of state and trait anxiety was each time measured with the STAI inventory. Results: The changes of the values of heart rate, blood pressure and salivary cortisol suggest that all trainings we stressful events for the patients, as they were not observed in the control session. But the gradual decrease in the levels of salivary cortisol and axiety as state after subsequent trainings may be signs of a gradual adaptation of the patient to the stressful situation. A lower cadence during the trainings compared to the control session was observed, however the speed of the cadence increased with each session. Conclusions: Ttrainings with the MOTEK CAREN system can be promising in the treatment of anxiety disorders. Of course in order to draw more evidence based conclusions this observations must be confirmed on a larger sample of patients

EVALUATION OF THE CORTISOL CONCENTRATIONS IN PATIENTS WITH SCHIZOPHRENIA

Introduction: The hypothalamus-pituitary-adrenal axis (HPAA) plays a pivotal role in response to a range of external and internal factors often described as a “stress”. Growing evidence in a literature, suggest various dysregulations of HPAA, in course of numerous mental disorders. Patients with schizophrenia and bipolar disorder seem to have elevated basal cortisol secretion, what might be caused by the diminution of glucocorticoid receptors’ amount. It was of the interest if the cortisol concentrations in patients with diagnosed schizophrenia who underwent treatment, differs from healthy individuals. Materials and methods: Two groups of participants were included into the study. First group (study) consisted of 10 patients with diagnosed schizophrenia and control group which included 38 healthy individuals. Study was divided into two stages, first one (pilot) included only control group, and utilized cortisol concentrations measurement from saliva, blood and 24h urine sample. Second part (main study) involved both groups although focused on a salivary cortisol concentrations. Results: A mean salivary cortisol concentration in patients with schizophrenia who underwent treatment was significantly lower in comparison with healthy individuals. Conclusions: Obtained results indicate that patients who underwent a treatment, and does not present notable clinical signs of schizophrenia may have moderately lowered levels of salivary cortisol. This may be a reflection of relenting psychotic symptoms as well as a direct effect of atypical antipsychotic drugs on a HPA axis activity