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61.
Polyurethane (PUR) composites were modified with 2 wt.% of lavender fillers functionalized with kaolinite (K) and hydroxyapatite (HA). The impact of lavender fillers on selected properties of PUR composites, such as rheological properties (dynamic viscosity, foaming behavior), mechanical properties (compressive strength, flexural strength, impact strength), insulation properties (thermal conductivity), thermal characteristic (temperature of thermal decomposition stages), flame retardancy (e.g., ignition time, limiting oxygen index, heat peak release) and performance properties (water uptake, contact angle) was investigated. Among all modified types of PUR composites, the greatest improvement was observed for PUR composites filled with lavender fillers functionalized with kaolinite and hydroxyapatite. For example, on the addition of functionalized lavender fillers, the compressive strength was enhanced by ~16–18%, flexural strength by ~9–12%, and impact strength by ~7%. Due to the functionalization of lavender filler with thermally stable flame retardant compounds, such modified PUR composites were characterized by higher temperatures of thermal decomposition. Most importantly, PUR composites filled with flame retardant compounds exhibited improved flame resistance characteristics—in both cases, the value of peak heat release was reduced by ~50%, while the value of total smoke release was reduced by ~30%. 相似文献
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63.
Karolina Wesoowska Marko Elovainio Kia Gluschkoff Laura Hietapakka Anu‐Marja Kaihlanen Salla Lehtoaro Tarja Heponiemi 《Research in nursing & health》2019,42(5):349-357
Cross‐cultural competence is an essential component of the nursing profession, but little is known about the specific psychosocial work characteristics that potentially promote or hinder such competence. In the present study, psychosocial work characteristics were based on Karasek's Job Demand—Control Model. The researchers examined whether Karasek's psychosocial work characteristics, such as high‐strain jobs, high‐strain isolated jobs, active jobs, and active collective jobs, are associated with cross‐cultural competence (empathy, skills, positive attitudes, and motivation), and whether there are differences between native and foreign‐born registered nurses (RN) in these potential associations. A random sample of 744 native RNs (91.0% women) and a total sample (n = 212) of foreign‐born RNs (94.3% women) working in Finland were used. Data were collected using a questionnaire and analyzed with a series of multiple linear regression analyses. High‐strain and high‐strain isolated jobs were negatively associated with all four dimensions of cross‐cultural competence. Active collective jobs, but not active jobs, were positively associated with cross‐cultural skills. There were no differences between native and migrant nurses in these associations. The psychosocial work environment is associated with cross‐cultural competence in both native and migrant nurses. Improvements in psychosocial working conditions, especially minimizing negative factors in the work environment, such as high‐strain and high‐strain isolated jobs, may need to be considered as a part of the efforts aimed to enhance cross‐cultural competence among nursing personnel. 相似文献
64.
65.
Zbigniew Śliwiński Małgorzata Starczyńska Ireneusz Kotela Tomasz Kowalski Karolina Kryś-Noszczyk Danuta Lietz-Kijak Edward Kijak Marta Makara-Studzińska 《International journal of occupational medicine and environmental health》2014,27(3):400-412
Objectives
Recently in Poland as a result of the high rate of aging population and high rates of morbidity, a growing demand for the physiotherapist profession is observed. The results of this study can be used to formulate principles for better organization of physiotherapist’s workplace in order to prevent occurrence of burnout. The aim of this study is to investigate the effect of gender on satisfaction with life and burnout among active physiotherapists.Material and Methods
The survey was anonymous and voluntary, and involved a group of 200 active physiotherapists working in health care units and educational centers in Po?land. The study group was selected randomly and incidentally. Each respondent received a demographic data sheet and a set of self-rating questionnaires (Life Satisfaction Questionnaire, Burnout Scale Inventory).Results
Burnout among men decreased along with increasing satisfaction with one’s work and occupation, friends, relatives and acquaintances, sexuality, and increased due to greater satisfaction with one’s housing status. Burnout among women decreased along with increasing satisfaction with one’s health, free time and friends, relatives and acquaintances, and increased due to work at a setting other than a health care unit or educational center. Statistical analysis failed to reveal any significant differences with regard to the BSI domains and with regard to the overall burnout index as well as with regard to the assessment of satisfaction with life between female and male physiotherapists.Conclusions
Satisfaction with children, marriage and partnership, with one’s work and occupation, interactions with friends, relatives and acquaintances and sexuality may contribute to reduction of burnout among men. Women who are satisfied with their children, family, health, free time and contacts with friends, relatives and acquaintances are less prone to burnout. Weak financial situation among women and deficiency of free time among men can induce burnout. Improving staff happiness may contribute to decreasing burnout. 相似文献66.
Jamie V. de Seymour Cathryn A. Conlon Karolina Sulek Silas G. Villas Bôas Lesley M. E. McCowan Louise C. Kenny Philip N. Baker 《Acta diabetologica》2014,51(5):887-890
Current early pregnancy screening tools to identify women at risk of developing gestational diabetes mellitus lack both specificity and sensitivity. As a result, the foetus and mother are often subjected to insult during disease progression, prior to diagnosis and treatment in later pregnancy. Metabolomics is an analytical approach, which allows for appraisal of small molecular mass compounds in a biofluid. The aim of this pilot study was to investigate the relationship between the early gestation serum metabolite profile and the subsequent development of gestational diabetes mellitus in the search for early pregnancy biomarkers and potential metabolic mechanisms. Our nested case-control study analysed maternal serum at 20 weeks’ gestation, obtained from the New Zealand cohort of the Screening for Pregnancy Endpoints study. Metabolomic profiling was performed using gas chromatography coupled to mass spectrometry, and metabolites were identified using R software and an in-house mass spectral library. Statistical analysis was performed using SPSS version 21.0. Forty-eight metabolites were identified in the serum samples. Itaconic acid (P = 0.0003), with a false discovery rate of 0.012, was found to be significantly more abundant in women who subsequently developed gestational diabetes mellitus, when compared to controls with uncomplicated pregnancies. The current pilot study found that itaconic acid may have potential as a novel biomarker in early pregnancy to predict the subsequent development of gestational diabetes mellitus. However, the findings from this pilot study require validation with a larger, diverse population before translation into the clinical setting. 相似文献
67.
Samira S. Valvassori Daniela V. Bavaresco Josiane Budni Tamara S. Bobsin Cinara L. Gonçalves Karolina V. de Freitas Emilio L. Streck João Quevedo 《Psychiatry research》2014
The neurobiological basis of bipolar disorder (BD) remains unknown; nevertheless, mitochondrial dysfunction has been identified in this disorder. Inactivation of any step in the tricarboxylic acid (TCA) cycle can impair mitochondrial ATP production. There is recent evidence indicating that PKC is an important therapeutic target for bipolar disorder. Therefore, we evaluated the effects of tamoxifen (TMX—a PKC inhibitor) on the activities of enzymes in the TCA cycle of rat brains subjected to an animal model of mania induced by amphetamine. In the reversal treatment, Wistar rats were first treated with d-AMPH or saliratsne (Sal) for 14 days. Thereafter, between days 8 and 14, the rats were administered TMX or Sal. The citrate synthase, succinate dehydrogenase, and malate dehydrogenase were evaluated in the frontal cortex, hippocampus, and striatum. The d-AMPH administration inhibited TCA cycle enzymes activity in all analyzed structures, and TMX reversed d-AMPH-induced dysfunction. In addition, we observed a negative correlation between d-AMPH-induced hyperactivity and the activity of these enzymes in the rat's brain. These findings suggested that TCA cycle enzymes inhibition can be an important link for the mitochondrial dysfunction seen in BD, and TMX exert protective effects against the d-AMPH-induced TCA cycle enzymes dysfunction. 相似文献
68.
Agata Mlynska Ramun Vainor Vytautas Rafanavi
ius Simonas Jocys Julija Janeiko Monika Petrauskyt Simas Bijeikis Piotras Cimmperman Birut Intait Karolina
ilionyt Aurin Barakauskien Raimundas Mekauskas Emilija Paberal Vita Paukonien 《American journal of reproductive immunology (New York, N.Y. : 1989)》2020,84(1)
69.
Markus Duechler Lukasz Peczek Karolina Zuk Izabela Zalesna Arkadiusz Jeziorski Malgorzata Czyz 《Immunobiology》2014
The immune system constitutes an important first-line defence against malignant transformation. However, cancer mediated immunosuppression inactivates the mechanisms of host immune surveillance. Cancer cells shut down anti-cancer immunity through direct cell–cell interactions with leukocytes and through soluble factors, establishing an immunosuppressive environment for unimpeded cancer growth. The composition of the immunosuppressive microenvironment in breast tumours is not well documented. To address this question, selected immunosuppressive factors were analyzed in tumour specimens from 33 breast cancer patients after surgery. The mRNA expression of selected genes was quantified in fresh tumour samples. Tumour infiltrating leukocytes were characterized by flow cytometry to identify regulatory T cells, myeloid derived suppressor cells, and type 2 macrophages. Statistical analysis revealed several interesting correlations between the studied parameters and clinical features. Overall, a surprisingly high degree of heterogeneity in the composition of the immunosuppressive environment was found across all breast cancer samples which adds to the complexity of this disease. The influence of the hypoxia inducible factors (HIFs) on the immune microenvironment was also addressed. The level of HIFs correlated with hormone receptor status and the expression of several immunosuppressive molecules. Targeting HIFs might not only sensitize breast tumours for radiation and chemotherapies but also interfere with cancer immunosuppression. 相似文献
70.
Sarcopenia, muscle wasting, and strength decline with age, is an important cause of loss of mobility in the elderly individuals. The underlying mechanisms are uncertain but likely to involve defects of motor nerve, neuromuscular junction, and muscle. Loss of motor neurons with age and subsequent denervation of skeletal muscle has been recognized as one of the contributing factors. This study investigated aspects of mitochondrial biology in spinal motor neurons from elderly subjects. We found that protein components of complex I of mitochondrial respiratory chain were reduced or absent in a proportion of aged motor neurons–a phenomenon not observed in fetal tissue. Further investigation showed that complex I-deficient cells had reduced mitochondrial DNA content and smaller soma size. We propose that mitochondrial dysfunction in these motor neurons could lead to the cell loss and ultimately denervation of muscle fibers. 相似文献