977 resultados para INTENSE
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Two new star-burst compounds based on 1,3,5-triazine core and carbazole end-capped phenylene ethynylene arms (1a and 1b) were synthesized and characterized. Their photophysical properties were investigated systematically via spectroscopic and theoretical methods. Both compounds exhibit strong 1π–π⁎ transitions in the UV region and intense 1π–π⁎/intramolecular charge transfer (1ICT) absorption bands in the UV–vis region. Introducing the carbazole end-capped phenylene ethynylene arm on the 1,3,5-triazine core causes a slight bathochromic shift and enhanced molar extinction coefficient of the 1π–π⁎/1ICT transition band. Both compounds are emissive in solution at room temperature and 77 K, which exhibit pronounced positive solvatochromic effect. The emitting state could be ascribed to 1ICT state in more polar solvent, and 1π–π⁎ state in low-polarity solvent. The high emission quantum yields (Φem=0.90~1.0) of 1a and 1b (in hexane and toluene) make them potential candidates as efficient light-emitting materials. The spectroscopic studies and theoretical calculations indicate that the photophysical properties of these compounds can be tuned by the carbazole end-capped phenylene ethynylene arm, which would also be useful for rational design of photofunctional materials.
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Introduction β-alanine (BAl) and NaHCO3 (SB) ingestion may provide performance benefits by enhancing concentrations of their respective physiochemical buffer counterparts, muscle carnosine and blood bicarbonate, counteracting acidosis during intense exercise. This study examined the effect of BAl and SB co-supplementation as an ergogenic strategy during high-intensity exercise. Methods Eight healthy males ingested either BAl (4.8 g day−1 for 4 weeks, increased to 6.4 g day−1 for 2 weeks) or placebo (Pl) (CaCO3) for 6 weeks, in a crossover design (6-week washout between supplements). After each chronic supplementation period participants performed two trials, each consisting of two intense exercise tests performed over consecutive days. Trials were separated by 1 week and consisted of a repeated sprint ability (RSA) test and cycling capacity test at 110 % Wmax (CCT110 %). Placebo (Pl) or SB (300 mg kgbw−1) was ingested prior to exercise in a crossover design to creating four supplement conditions (BAl-Pl, BAl-SB, Pl–Pl, Pl-SB). Results Carnosine increased in the gastrocnemius (n = 5) (p = 0.03) and soleus (n = 5) (p = 0.02) following BAl supplementation, and Pl-SB and BAl-SB ingestion elevated blood HCO3 − concentrations (p < 0.01). Although buffering capacity was elevated following both BAl and SB ingestion, performance improvement was only observed with BAl-Pl and BAl-SB increasing time to exhaustion of the CCT110 % test 14 and 16 %, respectively, compared to Pl–Pl (p < 0.01). Conclusion Supplementation of BAl and SB elevated buffering potential by increasing muscle carnosine and blood bicarbonate levels, respectively. BAl ingestion improved performance during the CCT110 %, with no aggregating effect of SB supplementation (p > 0.05). Performance was not different between treatments during the RSA test.
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Asymmetric tri-bridged diruthenium(III) complexes, [Ru2O(O(2)CR)(3)(en) (PPh(3))(2)](ClO4) (R = C6H4-p-X: X = OMe (1a), Me (1b); en=1,2-diaminoethane), were prepared and structurally characterized. Complex 1a 3CHCl(3), crystallizes in the triclinic space group P (1) over bar with a = 14.029(5), b = 14.205(5), c = 20.610(6) Angstrom, alpha= 107.26(3), beta = 101.84(3), gamma= 97.57(3)degrees, V= 3756(2) Angstrom(3) and Z = 2. The complex has an {Ru-2(mu-O)(mu-O(2)CR)(2)(2+)} core and exhibits [O4PRu(mu-O)RuPO2N2](+) coordination environments for the metal centers. The novel structural feature is the asymmetric arrangement of ligands at the terminal sites of the core which shows an Ru... Ru separation of 3.226(3) Angstrom and an Ru-O-Ru angle of 119.2(5)degrees. An intense visible band observed near 570 nm is assigned to a charge transfer transition involving the d pi-Ru(III) and p pi-mu-O Orbitals. Cyclic voltammetry of the complexes displays a reversible Ru-2(III,III) reversible arrow Ru-2(III,IV) couple near 0.8 V (versus SCE) in MeCN-0.1 M TBAP.
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Complexes [Ru2O(O2CR)(2)(1-MeIm)(6)](ClO4)(2) (la-c), [Ru2O(O2CR)(2)(ImH)(6)](ClO4)(2) (2a,b), and [Ru2O(O2CR)(2)(4-MeImH)(6)](ClO4)(2) (3a,b) with a (mu-oxo)bis(mu-carboxylato)diruthenium(III) core have been prepared by reacting Ru2Cl(O2CR)(4) with the corresponding imidazole base, viz. 1-methylimidazole (1-MeIm), imidazole (ImH), and 4-methylimidazole (4-MeImH) in methanol, followed by treatment with NaClO4 in water (R: Me, a; C6H4-p-OMe, b; C6H4-p-Me, c). Diruthenium(III,IV) complexes [Ru2O(O2CR)(2)(1-MeIm)(6)](ClO4)(3) (R: Me, 4a; C6H4-p-OMe, 4b; C6H4-p-Me, 4c) have been prepared by one-electron oxidation of 1 in MeCN with K2S2O8 in water. Complexes la, 2a . 3H(2)O, and 4a . 1.5H(2)O have been structurally characterized. Crystal data for the complexes are as follows: la, orthorhombic, P2(1)2(1)2(1), a = 7.659(3) Angstrom, b = 22.366(3) Angstrom, c = 23.688(2) Angstrom, V = 4058(2) Angstrom(3), Z = 4, R = 0.0475, and R-w = 0.0467 for 2669 reflections with F-o > 2 sigma(F-o); 2a . 3H(2)O, triclinic,
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High-resolution data from the TRMM satellite shows that sea surface temperature (SST) cools by 3 degrees C under the tracks of pre-monsoon tropical cyclones in the north Indian Ocean. However, even the strongest post-monsoon cyclones do not cool the open north Bay of Bengal. In this region, a shallow layer of freshwater from river runoff and monsoon rain caps a deep warm layer. Therefore, storm-induced mixing is not deep, and it entrains warm subsurface water. It is possible that the hydrography of the post-monsoon north Bay favours intense cyclones.
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The glass transition, whereby liquids transform into amorphous solids at low temperatures, is a subject of intense research despite decades of investigation. Explaining the enormous increase in relaxation times of a liquid upon supercooling is essential for understanding the glass transition. Although many theories, such as the Adam-Gibbs theory, have sought to relate growing relaxation times to length scales associated with spatial correlations in liquid structure or motion of molecules, the role of length scales in glassy dynamics is not well established. Recent studies of spatially correlated rearrangements of molecules leading to structural relaxation, termed ``spatially heterogeneous dynamics,'' provide fresh impetus in this direction. A powerful approach to extract length scales in critical phenomena is finite-size scaling, wherein a system is studied for sizes traversing the length scales of interest. We perform finite-size scaling for a realistic glass-former, using computer simulations, to evaluate the length scale associated with spatially heterogeneous dynamics, which grows as temperature decreases. However, relaxation times that also grow with decreasing temperature do not exhibit standard finite-size scaling with this length. We show that relaxation times are instead determined, for all studied system sizes and temperatures, by configurational entropy, in accordance with the Adam-Gibbs relation, but in disagreement with theoretical expectations based on spin-glass models that configurational entropy is not relevant at temperatures substantially above the critical temperature of mode-coupling theory. Our results provide new insights into the dynamics of glass-forming liquids and pose serious challenges to existing theoretical descriptions.
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A mathematician tends to have an intense relationship with treatises – one which is more akin to that of a historian than that of her colleagues in the ‘hard’ sciences. A book may be a century or two old and still be relevant as a source of information or inspiration, well-thumbed textbooks from youth might be still consulted decades later, and fierce arguments rage about relative merits of different treatments of the same subject. And much like any book-lover, a mathematician is forever arguing with herself whether she can afford to buy this volume or the other. When the price label is in dollars or euros and the salary paid in rupees, this last dilemma is particularly acute.
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DNA obtained from a human sputum isolate of Mycobacterium tuberculosis, NTI-64719, which showed extensive dissemination in the guinea pig model resulting in a high score for virulence was used to construct an expression library in the lambda ZAP vector. The size of DNA inserts in the library ranged from 1 to 3 kb, and recombinants represented 60% of the total plaques obtained. When probed with pooled serum from chronically infected tuberculosis patients, the library yielded 176 recombinants with a range of signal intensities. Among these, 93 recombinants were classified into 12 groups on the basis of DNA hybridization experiments, The polypeptides synthesized by the recombinants were predominantly LacZ fusion proteins, Serum obtained from patients who were clinically diagnosed to be in the early phase of M. tuberculosis infection was used to probe the 176 recombinants obtained. interestingly, some recombinants that gave very strong signals in the original screen did not react with early-phase serum; conversely, others whose signals were extremely weak in the original screen gave very intense signals with serum from recently infected patients, This indicates the differential nature of either the expression of these antigens or the immune response elicited by them as a function of disease progression.
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Background: Haemodialysis nurses form long term relationships with patients in a technologically complex work environment. Previous studies have highlighted that haemodialysis nurses face stressors related to the nature of their work and also their work environments leading to reported high levels of burnout. Using Kanters (1997) Structural Empowerment Theory as a guiding framework, the aim of this study was to explore the factors contributing to satisfaction with the work environment, job satisfaction, job stress and burnout in haemodialysis nurses. Methods: Using a sequential mixed-methods design, the first phase involved an on-line survey comprising demographic and work characteristics, Brisbane Practice Environment Measure (B-PEM), Index of Work Satisfaction(IWS), Nursing Stress Scale (NSS) and the Maslach Burnout Inventory (MBI). The second phase involved conducting eight semi-structured interviews with data thematically analyzed. Results: From the 417 nurses surveyed the majority were female (90.9 %), aged over 41 years of age (74.3 %), and 47.4 % had worked in haemodialysis for more than 10 years. Overall the work environment was perceived positively and there was a moderate level of job satisfaction. However levels of stress and emotional exhaustion (burnout) were high. Two themes, ability to care and feeling successful as a nurse, provided clarity to the level of job satisfaction found in phase 1. While two further themes, patients as quasi-family and intense working teams, explained why working as a haemodialysis nurse was both satisfying and stressful. Conclusions: Nurse managers can use these results to identify issues being experienced by haemodialysis nurses working in the unit they are supervising.
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Dimeric and monomeric forms of the enzyme triosephosphate isomerase (TIM) from Plasmodium falciparum (Pf) have been detected under conditions of nanoflow by electrospray mass spectrometry. The dimer (M = 55 663 Da) exhibits a narrow charge state distribution with intense peaks limited to values of 18(+) to 21(+), maximal intensity being observed for charge states 19(+) and 20(+). A monomeric species with a charge state distribution ranging from 11(+) to 16(+) is also observed, which may be assigned to folded dissociated subunits. Complete dimer dissociation results under normal electrospray condition. The effects of solution pH and source temperature have been investigated. The observation of four distinct charge state distributions which may be assigned to a dimer, folded monomer, partially folded monomer and unfolded monomer is reported. Circular dichromism and fluorescence studies of Pf TIM at low pH support the retention of substantial secondary and tertiary structures. Satellite peaks in mass spectra corresponding to hydrated species are also observed and isotope shift upon deuteration is demonstrated. The analysis of all available independent crystal structures of Pf TIM and TIMs from other organisms permits identification of structurally conserved water molecules. Hydration observed in the dimer and folded monomeric forms in the gas phase may correspond to these conserved sites.
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Sr2FeMoO6 oxides exhibit a half-metallic ferromagnetic (HM-FM) ground state and peculiar magnetic and magnetotransport properties, which are interesting for applications in the emerging field of spintronics and attractive for fundamental research in the field of heavily correlated electron systems. Sr2FeWO6 is an insulator with an antiferromagnetic (I-AFM) ground state. The solid solutions Sr2FeMoxW1-xO6 also have peculiar properties-W doping enhances chemical order which allows stabilization of the HM-FM state; as the W content exceeds a certain value a metal to insulator transition (MIT) occurs. The role of W in determining the physical properties of Sr2FeMoxW1-xO6 systems has been a matter of intense investigation. This work deals with the problem of the structural and electronic changes related to the MIT from a local perspective by means of x-ray absorption spectroscopy (XAS). This technique allows one to probe in detail the local structure and electronic modifications around selected absorber ions (W, Mo, Fe and Sr in our case). The results of XAS analysis in the whole composition range (0 <= x <= 1), in the near edge (XANES) and extended (EXAFS) regions, demonstrate an abrupt change of the local structure around the Fe and Mo sites at the critical composition, x(c). This change represents the microstructural counterpart associated with the MIT. Conversely, the local structure and electronic configuration of W ions remain unaltered in the whole composition range, suggesting indirect participation of W in the MIT.
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Dendrocalamus strictus and Bambusa arundinacea are monocarpic, gregariously flowering species of bamboo, common in the deciduous forests of the State of Karnataka in India. Their populations have significantly declined, especially since the last flowering. This decline parelleis increasing incidence of grazing, fire and extraction in recent decades. Results of an experiment in which the intensities of grazing and fire were varied, indicate that while grazing significantly depresses the survival of seedlings and the recruitment of new eulms of bamboo clumps, fire appeared to enhance seedling survival, presumably by reducing competition of lass fire-resistant species. New shoots of bamboo are destroyed by insects and a variety of herbivorous mammals. In areas of intense herbivore pressure, a bamboo clump initiates the production of a much larger number of new culrm, but results in many fewer and shorter intact culms. Extraction renders the new shoots more susceptible to herbivore pressure by removal of the protective covering of branches at the base of a bamboo clump. Hence, regular and extensive extraction by the paper mills in conjuction with intense grazing pressure strongly depresses the addition of new culms to bamboo clumps. Regulation of grazing in the forest by domestic livestock along with maintenance of the cover at the base of the clumps by extracting the culms at a higher level should reduce the rate of decline of the bamboo stocks.
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The main question of my doctoral thesis is whether ufology and UFO experiences are or can be explained as religious phenomena. My research is theoretical in the sense that I combine and systematise cultural scientific knowledge concerning the religiosity of ufology and UFO experiences and complete this theoretical effort with empirical subject matter. The research material for my study consists of theoretical literature and empirical texts written by ufologists and those who have had UFO experiences. I defined the material in a way that it became full and extensive with regard to ufology, stories about UFO experiences and the cultural scientific literature concerning them. In addition, I present a source criticism for the literature because it is in part informal. The method is analysing and synthesising the material in the context of spiral of hermeneutic inferential process. Definitions of religion, ufology and UFO experience, developed by myself, serve as guide lines for the process. The conclusions of my research are as follows. For the most part, ufology and UFO experiences belong to the category of religion and only a fraction of these instances can be explained as something else, for example psychiatric phenomena. From the religious viewpoint I explain ufology and UFO experiences on four different but interlinked levels: historical, comparative, sociological and psychological. Historically ufology and UFO experiences include esoteristic, Christian and folk religious elements. In addition UFO experiences have significant similarities with folk religious stories and shamanistic experiences. From the perspective of the sociology, of religion ufology and UFO experiences can be analysed as products of our scientific and technological Western culture. Social crisis and social psychological group mechanisms affect the appearance of ufological ideas and UFO experiences. Psychologically, in the background of religious UFO experiences there can be found several factors, such as wishful thinking. Concerning UFO sightings these are misinterpretations of certain ordinary and some rare or exotic natural and technical phenomena. Intense UFO experiences, such as UFO abductions, are stimulated for the most part by hallucinations, sleep paralysis disorders, lively fantasies (in case of fantasy prone personalities) and false memories. In group cases social pressure, small group delusion and the guilt of exposing the true nature of a story come into play. A UFO experience can be traumatising because of certain inferential mechanisms and cognitive dissonance involved in the process of conversion as a UFO experiencer. UFO religiosity is a cross cultural, widespread and a significant field of phenomena, which can offer insight about religious developments in the future. However, UFO religiosity has not been studied extensively. This research is one effort to address this lack of documentation. The motivation behind my thesis was to make ufology and UFO experiences more understandable.
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The theme of this doctoral thesis is the Finnish printmaking in the years 1930-1939. During this decade, there were approximately 100 artists making prints in Finland. Indeed, the period was an especially important one for printmaking. Associations for printmakers were founded in Helsinki and Turku, training in the field was launched, and the number of printmaking exhibitions increased considerably. Through their national organisations, Finnish printmakers participated in many exhibitions abroad, interaction with Nordic printmakers being especially intense. Thus, a firm basis for post-war developments was created. However, printmakers' activity- which had continued throughout the 1930s - declined notably after the Winter War broke out in the autumn of 1939. As a result, the period 1930-1939 forms a coherent and distinct unity in Finnish printmaking history. The study consists of two parts: the main text and an appendix in which the production of each printmaking artist active in the 1930s is examined separately. The study also includes a comprehensive list of the prints made in the course of the decade. One of the central themes is the printmakers' relationship to "Finnish nationalist" art and concepts of art in the 1930s. I analyse the various manifestations of this way of thinking in the visual arts of the period. Finnish fine art in the period between the world wars has usually been characterised as conservative, introverted and spiritually isolated from the modern European trends of the time. On the basis of this study, such a view is too simple. Many artists and printmakers adopted a modernistic notion of art that approached the newest in European modernism, including such trends as avant-garde classicism and general European new Objective Realism (Die neue Sachlichkeit). On the other hand, choosing Finnish nationalist motifs did not necessarily mean that the artist was opposed to modernism: modernist artists could still be interested in national themes. The relationship of 1930s printmaking to the world of nationalist ideas is examined in this doctoral thesis from several perspectives. Towards the end of the main text, I examine the issue from the point of view of selected artists. Another feature that emerged during the study and turned out to be surprisingly widespread was the close relationship of many artists to religious, theosophical and pantheistic views. I deal with this issue in greater detail through a few representative printmakers.
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Velum continues material experimentation with edible materials as explored within Formations: New Practices in Australian Architecture 2012. 1 The work employs the central theme of veiling as a ‘second skin’, an intermediary agent simultaneously engaging with Heideggerian themes of ‘nearness and revealing’ (1927, 1954). This second skin creates a liminality distorting everyday objects of popular culture and technological consumption. In doing so, the work puts forth multiple considerations, the figurative play upon consumption itself; the role of the strange and obscure to affect a deepening awareness of our accelerated consumption and experience; and more tangentially, questions surrounding imminent scenarios of hybridity between body and technology. Velum represents a recent focus of the authors’ creative practice, ‘Making Strange’ (Strange Making) published and presented elsewhere. Making Strange explores the sublime process, fundamental to both the final design outcome and the designing experience. The sublime process is seen as a leading, a physiological overpowering of self to a state of intense self-presence, often leading to self-transcendence or state of otherness. As such, the work engages with the body and materials, experimentally and in a trans-disciplinary manner to inform new material practice.
