Osmotic Properties of Polysaccharides Solutions

Osmotic properties of polysaccharides’ solutions and associated biopolymer-solvent and biopolymer-biopolymer type interaction are very important from a technological point of view. The knowledge of osmotic properties of these systems provides the basis to appropriate use of polysaccharides having comply with the relevant technology functions, impart the appropriate texture and forming the sensory properties of the final product. Furthermore, an important issue is the effect of time on the osmotic properties of polysaccharides’, because with time, the aforementioned effects may change. Membrane osmometry is one of the methods used in the studies of synthetic polymers to determine their average molecular mass and the degree of interaction between a polymer and a solvent. This method is successfully applied in the case of biopolymers that include polysaccharides. The existence of the osmotic pressure, formed by diffusion of solvent molecules through a semi-permeable membrane, is the basis of this method. Analysis and interpretation of osmometric research results is based on the van’t Hoff equation dependency of the concentration. The second virial coefficient obtained based on this relation allows characterisation of biopolymer-solvent interactions, and thus biopolymer tendency to solvation. The third virial coefficient provides information on mutual interactions between the biopolymer molecules, as well as its tendency to aggregate

Another look at boredom in language instruction: The role of the predictable and the unexpected

Although recent years have seen a growing interest in positive emotions in second or foreign language learning and teaching, negative emotions are always present in the classroom and they deserve to be investigated in their own right. The article focuses on boredom, a construct that has been explored in educational psychology but has received only scant attention from second language acquisition researchers. It reports a study which examined the changes in the levels of boredom experienced by 13 English majors in four EFL classes and the factors accounting for such changes. Using data obtained from a few different sources (i.e., boredom grids, narratives, interviews, class evaluations and lesson plans), it was found that although boredom can be attributed to different constellations of factors, it was mainly traced to repetitiveness, monotony and predictability of what transpired during a particular class

The associations of selected lifestyle patterns and lung cancer risk: An evidence-based update

Diagnosis of lung cancer (LC) has been fraught with difficulty and by the time of definitive diagnosis, most patients are in later stages of the disease. Epidemiological studies have demonstrated that lifestyle behaviors play an etiological role in LC risk; however data in the literature on this topic often appears inconclusive or require further study. Understanding of the mechanisms operating between lifestyle patterns and their impact on LC is important for the disease’s prevention and treatment. The purpose of this study was to review the current evidence on the role of diet, body mass index (BMI), physical activity, smoking, alcohol consumption, and sex hormone use in LC development based on meta-analyses, systematic reviews and previously published epidemiologic studies. Regarded as the foremost cause of LC, evidence from studies have indicated that tobacco smoking causes LC. Additionally, exposure to outdoor air pollution and/or occupational-related exposures increase LC risk. Further, frequent consumption of red meat, processed meat increases adenocarcinoma and squamous cell carcinoma. Inverse associations between the disease risk and BMI ≥25 kg/m2 , higher level of physical activity, and fruit and vegetable consumption with a high frequency were reported. Future studies are warranted to validate the association between histologic subtypes of LC and lifestyle patterns

Obesity, Physical Activity and Prostate Cancer: An Overview

Obesity and a lack of sufficient physical activity (PA) are recognized as risk factors for most civilization diseases, including cancer. This study synthesized the current evidence evaluating the relationship between excess body weight and prostate cancer (PCa) in the relation to the disease risk, progression, and mortality, and identifies biological plausibility of the association. We also estimated the importance of PA in intentional body weight loss. Several electronic major databases to identify eligible articles were searched until March 2022. A total 22 observational articles, the literature on the underlying biological mechanisms, and the crucial evidence of a role of PA in body weight maintenance and reduction were reviewed. The available knowledge suggests that association between body mass index and PCa is conflicting. However, the most research consistently shown that overweight/obesity was associated with higher risk of high-grade PCa and dying of PCa. Overweight/obesity can promote high-grade PCa through increased levels of secreted adipokines, increased formation of proinflammatory agents, and reduced concentration of adiponectin, among others. Being obese may by also linked with a higher risk of mortality. Exercise can decrease these health consequences related with obesity and may be effective in reduction of PCa-specific mortality, however, there are relative few studies on PA and PCa prevention among obese individuals

Tuwim on ethnic stereotypes

Kulturowe zróżnicowanie II Rzeczypospolitej, w której dużą część społeczeństwa, zwłaszcza w miastach, stanowiła ludność żydowska, znalazło różnowymiarowy oddźwięk w poezji Juliana Tuwima. Utwory o tematyce żydowskiej zajmują istotne miejsce w obrębie tekstów o problematyce społeczno-politycznej. Autor zwracał uwagę na różnice obyczajowe i mentalne, których konsekwencją są, niezależne od pochodzenia - polskiego czy żydowskiego - ortodoksyjne postawy wobec wszelkich odmienności. Ich źródłem są przede wszystkim ukształtowane w ciągu wieków uprzedzenia, przesądy i stereotypy. W swoich wierszach poeta dobitnie ujawniał opresywny aspekt każdej kultury, oddziałujący wielokierunkowo - wewnątrz diaspory czy pewnej grupy społecznej oraz na zewnątrz - w dwustronnych relacjach z Innym. Wskazywał tym samym na zagrożenie, jakim jest poddanie kultury manipulacji, ideologizacji, podporządkowanie polityce lub interesom ekonomicznym, stając się w ten sposób niebezpiecznym narzędziem skierowanym przeciw człowiekowi.The cultural diversity of the Second Polish Republic, in which a large part of society, especially in cities, was of Jewish origin, was variously reflected in Julian Tuwim’s poetry. Works devoted to the Jewish culture were an important part of Tuwim’s socio-political texts. The author pointed out the cultural and mental differences, whose consequences were - irrespective of their origin, whether Polish or Jewish - some orthodox attitudes towards dissimilarity. They originated, first and foremost, from the prejudices, superstitions and stereotypes formed over the ages. In his poems, Tuwim emphatically revealed the oppressive aspect of any culture, acting in many directions: within a given diaspora or social group as well as outside, in the interaction with the Other. In this way, he pointed at the threat which lies in a culture being manipulated, ideologized, subjected to politics or economic interests, and thus becoming a dangerous tool aimed against people

Umowy dystrybucyjne na obszar Unii Europejskiej: ograniczenia konkurencji w postanowieniach o prawach własności intelektualnej

Artykuł omawia typowe postanowienia dotyczące praw własności intelektualnej, które pojawiają się w umowach dystrybucyjnych na obszar Unii Europejskiej, a które mogą stanowić ograniczenie konkurencji. Uwzględniono m.in. przyjęty sposób analizy nakładających się regulacji krajowych z zakresu prawa własności intelektualnej oraz unijnego prawa ochrony konkurencji, a także warunki wyłączenia spod zakazu porozumień ograniczających konkurencję. Celem artykułu jest przybliżenie problematyki w świetle praktyki decyzyjnej Komisji Europejskiej i sądów unijnych

Un análisis de los efectos predictivos de la tenacidad general y la tenacidad sobre la L2 en la motivación: El efecto mediador del conocimiento auto-percibido de la L2

Following a recent surge of interest in the role of personality traits in second language learning, this study focuses on L2 grit as an important individual difference factor that is gaining growing recognition among second language acquisition researchers. Adopting a mixed-methods approach, we examined the predictive effects of general grit and L2 grit on motivated behavior among 549 advanced Polish university students majoring in English and the extent to which these effects were mediated by self-perceived proficiency. Data were collected by means of the Grit Scale (Duckworth et al., 2007), the L2 Grit Scale (Teimouri et al., 2022), the motivated behavior scale (Taguchi et al., 2009), and semi-structured interviews. Quantitative analysis demonstrated that general grit and L2 grit significantly co-predicted motivated behavior, with the effect of L2 grit being more pronounced. However, differences were found for students representing different proficiency levels. The results were corroborated by qualitative analysis of interview data.Ante el reciente aumento en el interés por el papel que desempeñan los rasgos de personalidad en el aprendizaje de una segunda lengua (L2), el presente trabajo se centra en la tenacidad en la L2 (L2 grit), un factor importante de diferencias individuales cada vez más reconocido entre los investigadores de la adquisición de una L2. Adoptando un enfoque metodológico mixto, se examinaron los efectos predictivos de la tenacidad general y la tenacidad en la L2 sobre la motivación de 549 estudiantes universitarios polacos de Estudios Ingleses con nivel avanzado de conocimiento de la lengua, y se analizó el grado en que dichos efectos estaban mediados por su autopercepción del nivel de conocimiento de la L2. Los datos se recogieron mediante la Escala de Tenacidad (Duckworth et al., 2007), la Escala de Tenacidad en L2 (Teimouri et al., 2022), la Escala de Motivación (Taguchi et al., 2009) y entrevistas semiestructuradas. El análisis cuantitativo demostró que la tenacidad general y la tenacidad en la L2 predijeron de forma conjunta y de manera significativa la motivación de los aprendices, siendo más pronunciado el efecto de la tenacidad en la L2. Sin embargo, se encontraron diferencias entre los participantes dependiendo de su nivel de conocimiento de la L2. Estos resultados se corroboraron mediante el análisis cualitativo de los datos de las entrevistas

Exercise-induced oxidative stress and melatonin supplementation: current evidence

Melatonin possesses the indoleamine structure and exerts antioxidant and anti-inflammatory actions and other physiological properties. Physical exercise can influence secretion of melatonin. Melatonin is used as a natural supplement among athletes to regulate sleep cycles and protect muscles against oxidative damage. Despite decades of research, there is still a lack of a comprehensive and critical review on melatonin supplementation and physical activity relationship. The aim of this literature review is to examine the antioxidant, anti-inflammatory and other biological functions played by melatonin with reference to the effect of physical exercise on melatonin secretion and the effect of this compound supplementation on exercise-induced oxidative stress in athletes. Evidence shows that intense exercises disturb antioxidant status of competitive athletes, whereas supplementation with melatonin strengthens antioxidant status in trained athletes in various sports as the compound showed high potency in reduction of the oxidative stress and inflammation markers generated during intense and prolonged exercise

Psychological Stress and Cellular Aging in Cancer: A Meta-Analysis

Background. Epidemiological evidence continues to accumulate on the effect of psychosocial and behavioral factors in relation to cancer risk, progression, and mortality. Material and Methods. This article presents the current evidence on the relationship between psychological stress and the risk of cancer and cellular aging process. Ten databases were searched to identify publications up to September 2019. References from retrieved articles were also reviewed. We included nine review papers and 26 cohort or case-control studies based on inclusion/exclusion criteria. Results. Results of previously published review articles did not show consistent evidence for the association between cancer risk and psychological stress, while previous evidence is stronger regarding the role of chronic psychological stress on cancer growth and metastasis and aging. In seven observational studies, severe life events, anxiety, depression, insufficient social support perception, or avoiding coping strategy were significantly associated with breast cancer risk. For other specific types of cancer, 11 studies reported increased risk factors for stressful life events, and two others found increased mortality or a decline in treatment adherence. Conclusions. Recent epidemiological evidence generally suggests psychosocial factors may be considered risk factors for specific types of cancer and play a key role in the cellular aging process. Understanding molecular mechanisms of the stress interaction is important in cancer management and prevention. The psychological stressors should be considered when developing or evaluating change in psychosocial practice

Antioxidative properties of phenolic compounds and their effect on oxidative stress induced by severe physical exercise

Extensive research has found strongly increased generation of reactive oxygen species, free radicals, and reactive nitrogen species during acute physical exercise that can lead to oxidative stress (OS) and impair muscle function. Polyphenols (PCs), the most abundant antioxidants in the human diet, are of increasing interest to athletes as antioxidants. Current literature suggests that antioxidants supplementation can effectively modulate these processes. This overview summarizes the actual knowledge of chemical and biomechanical properties of PCs and their impact as supplements on acute exercise-induced OS, inflammation control, and exercise performance. Evidence maintains that PC supplements have high potency to positively impact redox homeostasis and improve skeletal muscle\u27s physiological and physical functions. However, many studies have failed to present improvement in physical performance. Eleven of 15 representative experimental studies reported a reduction of severe exercise-induced OS and inflammation markers or enhancement of total antioxidant capacity; four of eight studies found improvement in exercise performance outcomes. Further studies should be continued to address a safe, optimal PC dosage, supplementation timing during a severe training program in different sports disciplines, and effects on performance response and adaptations of skeletal muscle to exercise