69 research outputs found

    Phases of supersymmetric O(N) theories

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    We perform a global renormalization group study of O(N) symmetric Wess-Zumino theories and their phases in three euclidean dimensions. At infinite N the theory is solved exactly. The phases and phase transitions are worked out for finite and infinite short-distance cutoffs. A distinctive new feature arises at strong coupling, where the effective superfield potential becomes multi-valued, signalled by divergences in the fermion-boson interaction. Our findings resolve the long-standing puzzle about the occurrence of degenerate O(N) symmetric phases. At finite N, we find a strongly-coupled fixed point in the local potential approximation and explain its impact on the phase transition. We also examine the possibility for a supersymmetric Bardeen-Moshe-Bander phenomenon, and relate our findings with the spontaneous breaking of supersymmetry in other models.Comment: 23 pages, 18 figure

    On the relevance of polyynyl-substituted PAHs to astrophysics

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    We report on the absorption spectra of the polycyclic aromatic hydrocarbon (PAH) molecules anthracene, phenanthrene, and pyrene carrying either an ethynyl (-C2H) or a butadiynyl (-C4H) group. Measurements were carried out in the mid infrared at room temperature on grains embedded in CsI pellets and in the near ultraviolet at cryogenic temperature on molecules isolated in Ne matrices. The infrared measurements show that interstellar populations of polyynyl-substituted PAHs would give rise to collective features in the same way non-substituted PAHs give rise to the aromatic infrared bands. The main features characteristic of the substituted molecules correspond to the acetylenic CH stretching mode near 3.05 mum and to the almost isoenergetic acetylenic CCH in- and out-of-plane bending modes near 15.9 mum. Sub-populations defined by the length of the polyynyl side group cause collective features which correspond to the various acetylenic CC stretching modes. The ultraviolet spectra reveal that the addition of an ethynyl group to a non-substituted PAH molecule results in all its electronic transitions being redshifted. Due to fast internal energy conversion, the bands at shorter wavelengths are significantly broadened. Those at longer wavelengths are only barely affected in this respect. As a consequence, their relative peak absorption increases. The substitution with the longer butadiynyl chain causes the same effects with a larger magnitude, resulting in the spectra to show a prominent if not dominating pi-pi* transition at long wavelength. After discussing the relevance of polyynyl-substituted PAHs to astrophysics, we conclude that this class of highly conjugated, unsaturated molecules are valid candidates for the carriers of the diffuse interstellar bands.Comment: 29 pages, 9 figures, accepted for publication in ApJ 2 April 201

    Exploring the Creative Process: Integrating Psychometric and Eye-Tracking Approaches

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    This exploratory study aims at integrating the psychometric approach to studying creativity with an eye-tracking methodology and thinking-aloud protocols to potentially untangle the nuances of the creative process. Wearing eye-tracking glasses, one hundred adults solved a drawing creativity test – The Test of Creative Thinking-Drawing Production (TCT-DP) – and provided spontaneous comments during this process. Indices of visual activity collected during the eye-tracking phase explained a substantial amount of variance in psychometric scores obtained in the test. More importantly, however, clear signs of methodological synergy were observed when all three sources (psychometrics, eye-tracking, and coded thinking-aloud statements) were integrated. The findings illustrate benefits of using a blended methodology for a more insightful analysis of creative processes, including creative learning and creative problem-solving

    Effect of iodothyronine hormone status on doxorubicin related cardiotoxicity

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    The anthracycline anticancer agent doxorubicin has been recognised to induce a dose-dependent cardiotoxicity. The chronic form of such complication is characterized by an irreversible cardiac damage and congestive heart failure. Although the pathogenesis of anthracycline cardiotoxicity seems to be multifactorial, the pivotal role has been attributed to reactive oxygen species formation. Because redox equilibrium in cardiomyocytes may be regulated via iodothyronine hormones, the aim of the study was to appraise the effect of hypothyroidism on heart damages induced by doxorubicin. The rats received methimazole in drinking water (0.001 and 0.025%) after doxorubicin administration (2.0, 5.0 and 15 mg/kg). The cardiac morphology and blood biochemical markers of heart damage were assessed. Decreased levels of iodothyronine hormones had not significant impact on cardiac morphological changes and no effect on the level of B-type natriuretic peptide in rats receiving doxorubicin. Lower hormonal levels had sporadic, diverse effect on blood transaminases, lactate dehydrogenase and creatine kinase levels, but any relation to time, doxorubicin doses and hypothyroid status was found. Hypothyreosis leads to increase in fatty acid binding protein in rats receiving higher dose of doxorubicin. Hypothyreosis had no effect on heart stretching and on necrosis at morphological level, but caused biochemical symptoms of cardiomyocyte necrosis in rats receiving doxorubicin

    5-Hydroxymethylfurfural (HMF) formation during subcritical water extraction

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    The aim of this study was to investigate the effect of material type (artichoke leave, lemon peel, flaxseed meal), extraction temperature (50, 100, 120, 140, 160, 180, 200 C) and static extraction time (5, 15, 30, 45 min) on 5-hydroxymethylfurfural (5-HMF) formation during subcritical water extraction. 5-HMF content of artichoke leave and lemon peel extracts increased 7.2 and 26.1 times with the rise of extraction temperature from 160 to 180 C for 5 min during subcritical water extraction, respectively. Besides, 5-HMF content of artichoke leave, lemon peel and flaxseed meal extracts increased 1.4, 2.0 and 4.5 times as static extraction time increased from 15 to 45 min at 180 C during subcritical water extraction, respectively. The highest 5-HMF content of artichoke leave and lemon peel extracts were obtained as 58.83 and 231.21 mg/L at 180 C and 45 min, respectively. However, for flaxseed meal, the highest 5-HMF content (222.94 mg/L) was obtained at 200 C and 15 min during subcritical water extraction.Project Nos. 2014.M80.02.03, 2014.M80.02.04 by Artvin Coruh University Scientific Research Project Uni

    Influence of quorum sensing signal molecules on biofilm formation in Proteus mirabilis O18

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    The influence of basis of quorum sensing molecules on Proteus strains is much less known as compared to Pseudomonas or Escherichia. We have previously shown that a series of acylated homoserine lactones (acyl-HSL) does not influence the ureolytic, proteolytic, or hemolytic abilities, and that the swarming motility of Proteus mirabilis rods is strain specific. The aim of the presented study was to find out if the presence of a series of acyl-HSL influences biofilm formation of P. mirabilis laboratory strain belonging to O18 serogroup. This serogroup is characterized by the presence of a unique non-carbohydrate component, namely phosphocholine. Escherichia coli and P. mirabilis O18 strains used in this work contains cloned plasmids encoding fluorescent protein genes with constitutive gene expression. In mixed biofilms in stationary and continuous flow conditions, P. mirabilis O18 overgrow whole culture. P. mirabilis O18 strain has genetically proved a presence of AI–2 quorum sensing system. Differences in biofilm structure were observed depending on the biofilm type and culture methods. From tested acylated homoserine lactones (BHL, HHL, OHL, DHL, dDHL, tDHL), a significant influence had BHL on thickness, structure, and the amount of exopolysaccharides produced by biofilms formed by P. mirabilis O18 pDsRed2

    Taqman Real-Time PCR Detects Avipoxvirus DNA in Blood of Hawaìi `Amakihi (Hemignathus virens)

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    Margaret E. M. Farias et al...Background Avipoxvirus sp. is a significant threat to endemic bird populations on several groups of islands worldwide, including Hawaìi, the Galapagos Islands, and the Canary Islands. Accurate identification and genotyping of Avipoxvirus is critical to the study of this disease and how it interacts with other pathogens, but currently available methods rely on invasive sampling of pox-like lesions and may be especially harmful in smaller birds. Methodology/Principal Findings Here, we present a nested TaqMan Real-Time PCR for the detection of the Avipoxvirus 4b core protein gene in archived blood samples from Hawaiian birds. The method was successful in amplifying Avipoxvirus DNA from packed blood cells of one of seven Hawaiian honeycreepers with confirmed Avipoxvirus infections and 13 of 28 Hawaìi `amakihi (Hemignathus virens) with suspected Avipoxvirus infections based on the presence of pox-like lesions. Mixed genotype infections have not previously been documented in Hawaìi but were observed in two individuals in this study. Conclusions/Significance We anticipate that this method will be applicable to other closely related strains of Avipoxvirus and will become an important and useful tool in global studies of the epidemiology of Avipoxvirus.Funding for this study was provided by: U.S. Geological Survey, Pacific Island Ecosystems Research Center (biology.usgs.gov/pierc/); U.S. Geological Survey Wildlife (biology.usgs.gov/wter/) and Invasive Species (biology.usgs.gov/invasive/) Programs; National Science Foundation (DEB0083944, www.nsf.gov); NIH/NCRR IDeA Networks of Biomedical Research Excellence (INBRE), P20RR016467 (http://www.ncrr.nih.gov/research_infrast​ructure/institutional_development_award/​idea_networks_of_biomedical_research_exc​ellence/). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewe

    Factors influencing physical activity and rehabilitation in survivors of critical illness: a systematic review of quantitative and qualitative studies

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    PURPOSE: To identify, evaluate and synthesise studies examining the barriers and enablers for survivors of critical illness to participate in physical activity in the ICU and post-ICU settings from the perspective of patients, caregivers and healthcare providers. METHODS: Systematic review of articles using five electronic databases: MEDLINE, CINAHL, EMBASE, Cochrane Library, Scopus. Quantitative and qualitative studies that were published in English in a peer-reviewed journal and assessed barriers or enablers for survivors of critical illness to perform physical activity were included. Prospero ID: CRD42016035454. RESULTS: Eighty-nine papers were included. Five major themes and 28 sub-themes were identified, encompassing: (1) patient physical and psychological capability to perform physical activity, including delirium, sedation, illness severity, comorbidities, weakness, anxiety, confidence and motivation; (2) safety influences, including physiological stability and concern for lines, e.g. risk of dislodgement; (3) culture and team influences, including leadership, interprofessional communication, administrative buy-in, clinician expertise and knowledge; (4) motivation and beliefs regarding the benefits/risks; and (5) environmental influences, including funding, access to rehabilitation programs, staffing and equipment. CONCLUSIONS: The main barriers identified were patient physical and psychological capability to perform physical activity, safety concerns, lack of leadership and ICU culture of mobility, lack of interprofessional communication, expertise and knowledge, and lack of staffing/equipment and funding to provide rehabilitation programs. Barriers and enablers are multidimensional and span diverse factors. The majority of these barriers are modifiable and can be targeted in future clinical practice

    Anew functional ingredients - sea carotenoids

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    Rozwijający się rynek żywności funkcjonalnej i suplementów diety zmusza producentów do poszukiwania nowych substancji, które spełnią wymagania konsumentów w zakresie pozytywnego oddziałania na organizm i bezpieczeństwa stosowania. Karotenoidy z alg morskich, astaksantyna ifukoksantyna, są nowością na rynku światowym. Dostarczone do organizmu człowieka mogą pełnić bardzo ważną rolę w prewencji i leczeniu wielu chorób cywilizacyjnych. Oba związki są silnymi przećiwutleniaczami, a dzięki tym właściwościom wykazują działanie m. in.: kardioprotekcyjne, przeciwzapalne, przeciwnowotworowe, wspomagające redukcję masy ciała, regulujące poziom glukozy we krwi.The increasing market of functional food and supplements of the diet is forcing the producers searching the new substances, which consumers would appreciate for positive influence of the body and safety use. Sea algae carotenoids, astaxanthin and fucoxanthin, are the novelty on the world market, in the human body they are able to play very important role in the prevention and the treatment of many civilization diseases. Both are a strong antioxidants, thanks to this properties, they had an effect: cardioprotective, anti-inflammatory, anticancerogenic, weight management, regulating the level of glucose in blood

    The influence of technological process on polyphenolic compounds content and antioxidant properties in apples and apple preserves

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    W pracy zaprezentowanej w artykule porównano zawartość związków polifenolowych i aktywność przeciwutleniającą świeżych jabłek oraz produktów ich przetworzenia, otrzymanych w skali laboratoryjnej. Na podstawie uzyskanych wyników stwierdzono, że jabłka i przetwory jabłkowe są dobrym źródłem substancji bioaktywnych, o charakterze przeciwutleniaczy, jednak ich ilość zależy od odmiany. Straty związków polifenolowych ogółem spowodowane procesem technologicznym wynoszą w zależności od odmiany od ok. 30-35%. Proces pasteryzacji powoduje zbliżone straty związków polifenolowych do strat powstałych podczas gotowania owoców świeżych. Uzyskane wyniki mogą mieć znaczenie aplikacyjne w projektowaniu nowych asortymentów przetworów jabłkowych.In this work the content of polyphenolic compounds and antioxidant properties of fresh apples and apples preserves were compared. On the basis of the data received found that apples and apple preserves are a good source of bioactive components, with antioxidants character, but their content are determined on fruit variety. The wastes of polyphenolic compounds are caused by technological process and amounted about 30-35% in dependence on variety. The pasteurization process caused polyphenolic compounds wastes similar to wastes caused cooking fresh fruit. Obtained results could have significance application in new assortment of apples preserves design
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