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991.
The role of anticipatory auditory imagery in music-like sequential action was investigated by examining timing accuracy and kinematics using a motion capture system. Musicians responded to metronomic pacing signals by producing three unpaced taps on three vertically aligned keys at the given tempo. Taps triggered tones in two out of three blocked feedback conditions, where key-to-tone mappings were compatible or incompatible in terms of spatial and pitch height. Results indicate that, while timing was most accurate without tones, movements were smaller in amplitude and less forceful (i.e., acceleration prior to impact was lowest) when tones were present. Moreover, timing was more accurate and movements were less forceful with compatible than with incompatible auditory feedback. Observing these effects at the first tap (before tone onset) suggests that anticipatory auditory imagery modulates the temporal kinematics of regularly timed auditory action sequences, like those found in music. Such cross-modal ideomotor processes may function to facilitate planning efficiency and biomechanical economy in voluntary action. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Electrochemical promotion of catalysis is a unique tool for the in situ tuning of catalytic activity of electronically conductive metals or metal oxides in contact with solid electrolytes. The importance of electrochemical promotion to heterogeneous catalysis, surface science and electrochemistry research for the investigation of spillover phenomena and metal–support interactions is well recognized. The unlimited applications of the phenomenon, in terms of catalysts, solid electrolytes or catalytic reactions selection, has been proven through numerous laboratory investigations. Though the molecular origin of electrochemical promotion has been revealed, using a variety of experimental techniques and theoretical calculations, there is still a shortage on the practical level. However, in the last decade, spectacular progress has been made in the development of effective, low cost electropromoted catalysts and reactors. The major technological advances and milestones towards the practical utilization of electrochemical promotion are surveyed in view of electrocatalysts development and system/reactor engineering. 相似文献
993.
This article reviews the potential for establishing in the British planning regime a universal obligation for environmental compensation of greenfield development, drawing on the emerging experience of Germany with this measure. It is concluded that, subject to compensation being employed only after the possibilities of avoidance and mitigation have been exhausted, it would help to secure local environmental capital against erosion by cumulated small developments, which pass through the net of environmental assessment. It is suggested that it might do this better than a greenfield tax. It might also contribute to managing land consumption per se. 相似文献
994.
Relativistic effects are known to play a fundamental role in determining the properties of gold, even imparting it with a yellow color. Here we use ab initio calculations and an evolving theory that allows the electron charge density to be partitioned into chemically meaningful structures to show that these effects also give rise to gold's well-known resistance to oxidation by making oxygen insoluble in gold. We go on to show that silver, despite having the same lattice constant and oxygen binding energy as gold, is extremely susceptible to oxidation because the relativistic effects in silver are smaller than in gold. 相似文献
995.
Simone Krüger K. Brademann-Jock W. Rauth T. Klimmasch P. Krüger 《Journal of Coatings Technology and Research》2008,5(1):11-16
Thermally stimulated luminescence (TL) can be used to detect damage in the early stages of degradation after artificial weathering,
and to analyze the efficiency of stabilizers used in automotive coatings. TL is particularly suitable for this task due to
its inherent high sensitivity to structural, morphological, and chemical changes in macromolecular chains. In this work, TL
measurements were carried out for different automotive coatings to follow their degradation progression during artificial
weathering. The TL results demonstrate high sensitivity to parameters like stabilizers, matrices, hardeners, and weathering
time, and provide an opportunity to monitor the early stages of damage in polymers, which therefore reduce the time required
for further outdoor weathering tests. 相似文献
996.
997.
The knowledge of operational experts plays a fundamental role in performing safety assessments in safety critical organizations. The complexity and socio-technical nature of such systems produce hazardous situations which require a thorough understanding of concrete operational scenarios and cannot be anticipated by simply analysing single failures of specific functions. This paper addresses some limitations regarding state-of-the-art safety assessment techniques, with special reference to the adoption of “chain of event” models in accident causation (widely criticised by many authors), to the use of severity classes and to the adoption of the worst credible effect criterion. Such methods tend to assume a linear link between single hazards considered in isolation and corresponding consequences for safety, thus neglecting the intrinsic complexity of the systems under analysis and reducing the opportunities for an effective involvement of operational experts. An alternative approach is proposed to overcome these limitations, by distinguishing different typologies of hazards and integrating the analysis of single functions with the study of concrete operational scenarios. 相似文献
998.
Simone Caramel Stagnaro Sergio Pyatakovich Felix A. Yakunchenko T.I. Makkonen K.F. Moryleva O.N. 《红外与毫米波学报》2014,33(1):1-18
The effects of background millimeter radiations (BMR) in patients with coronary artery disease (CAD), hypertension and in subjects with Inherited real risk of CAD, were investigated through invariant statistic measures, typical of nonlinear dynamics analysis of biological systems. The experimental evidences show that BMR ameliorate the nonlinear complexity in biosystems, recognized sign of physiological behavior, by increasing both the rate of unpredictability of heart rate variability (HRV) in patients with metabolic syndrome and the fractal dimension of coronary microvessel oscillations in subjects with pre-metabolic syndrome, healing their genetic alteration and CAD Inherited real risk. 相似文献
999.
Simone S. Nascimento Adriano A. S. Araújo Renan G. Brito Mairim R. Serafini Paula P. Menezes Josimari M. DeSantana Waldecy Lucca Júnior Pericles B. Alves Arie F. Blank Rita C. M. Oliveira Aldeidia P. Oliveira Ricardo L. C. Albuquerque-Júnior Jackson R. G. S. Almeida Lucindo J. Quintans-Júnior 《International journal of molecular sciences》2015,16(1):547-563
O. basilicum leaves produce essential oils (LEO) rich in monoterpenes. The short half-life and water insolubility are limitations for LEO medical uses. β-Cyclodextrin (β-CD) has been employed to improve the pharmacological properties of LEO. We assessed the antihyperalgesic profile of LEO, isolated or complexed in β-CD (LEO/β-CD), on an animal model for fibromyalgia. Behavioral tests: mice were treated every day with either LEO/β-CD (25, 50 or 100 mg/kg, p.o.), LEO (25 mg/kg, p.o.), tramadol (TRM 4 mg/kg, i.p.) or vehicle (saline), and 60 min after treatment behavioral parameters were assessed. Therefore, mice were evaluated for mechanical hyperalgesia (von Frey), motor coordination (Rota-rod) and muscle strength (Grip Strength Metter) in a mice fibromyalgia model. After 27 days, we evaluated the central nervous system (CNS) pathways involved in the effect induced by experimental drugs through immunofluorescence protocol to Fos protein. The differential scanning analysis (DSC), thermogravimetry/derivate thermogravimetry (TG/DTG) and infrared absorption spectroscopy (FTIR) curves indicated that the products prepared were able to incorporate the LEO efficiently. Oral treatment with LEO or LEO-βCD, at all doses tested, produced a significant reduction of mechanical hyperalgesia and we were able to significantly increase Fos protein expression. Together, our results provide evidence that LEO, isolated or complexed with β-CD, produces analgesic effects on chronic non-inflammatory pain as fibromyalgia. 相似文献
1000.
Structural Design,Synthesis and Structure–Activity Relationships of Thiazolidinones with Enhanced Anti‐Trypanosoma cruzi Activity 下载免费PDF全文
Dr. Diogo Rodrigo Magalhães Moreira Prof. Ana Cristina Lima Leite Dr. Marcos Verissimo Oliveira Cardoso Prof. Rajendra Mohan Srivastava Prof. Marcelo Zaldini Hernandes Marcelo Montenegro Rabello Luana Faria da Cruz Prof. Rafaela Salgado Ferreira Prof. Carlos Alberto de Simone Cássio Santana Meira Dr. Elisalva Teixeira Guimaraes Aline Caroline da Silva Thiago André Ramos dos Santos Dr. Valéria Rêgo Alves Pereira Dr. Milena Botelho Pereira Soares 《ChemMedChem》2014,9(1):177-188
Pharmacological treatment of Chagas disease is based on benznidazole, which displays poor efficacy when administered during the chronic phase of infection. Therefore, the development of new therapeutic options is needed. This study reports on the structural design and synthesis of a new class of anti‐Trypanosoma cruzi thiazolidinones ( 4 a – p ). (2‐[2‐Phenoxy‐1‐(4‐bromophenyl)ethylidene)hydrazono]‐5‐ethylthiazolidin‐4‐one ( 4 h ) and (2‐[2‐phenoxy‐1‐(4‐phenylphenyl)ethylidene)hydrazono]‐5‐ethylthiazolidin‐4‐one ( 4 l ) were the most potent compounds, resulting in reduced epimastigote proliferation and were toxic for trypomastigotes at concentrations below 10 μM , while they did not display host cell toxicity up to 200 μM . Thiazolidinone 4 h was able to reduce the in vitro parasite burden and the blood parasitemia in mice with similar potency to benznidazole. More importantly, T. cruzi infection reduction was achieved without exhibiting mouse toxicity. Regarding the molecular mechanism of action, these thiazolidinones did not inhibit cruzain activity, which is the major trypanosomal protease. However, investigating the cellular mechanism of action, thiazolidinones altered Golgi complex and endoplasmic reticulum (ER) morphology, produced atypical cytosolic vacuoles, as well as induced necrotic parasite death. This structural design employed for the new anti‐T. cruzi thiazolidinones ( 4 a – p ) led to the identification of compounds with enhanced potency and selectivity compared to first‐generation thiazolidinones. These compounds did not inhibit cruzain activity, but exhibited strong antiparasitic activity by acting as parasiticidal agents and inducing a necrotic parasite cell death. 相似文献