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1.
Classical violins produced by makers such as Antonio Stradivari and Guarneri del Gesu have long been considered the epitome of the luthier''s art and the expressive tool of choice for the most celebrated violinists. It has been speculated these makers had access to wood that was unique in some way and that this was responsible for their acclaimed tonal characteristics. In an attempt to discern whether the above conjecture is true, we analyzed 17 modern and classical Dutch, German, Austrian and French violins by wood densitometry using computed tomography and correlated these results with our previous study of modern and Cremonese violins; in all studying 30 instruments of the violin family. In order to make this comparison possible we developed methods to cross calibrate results from different CT manufacturers using calibration wood pieces. We found no significant differences in median densities between modern and classical violins, or between classical violins from different origins. These results suggest that it is unlikely classical Cremonese makers had access to wood with significantly different wood density characteristics than that available to contemporaneous or modern makers.  相似文献   

2.
Violin design has been in flux since the production of the first instruments in 16th century Italy. Numerous innovations have improved the acoustical properties and playability of violins. Yet, other attributes of the violin affect its performance less, and with fewer constraints, are potentially more sensitive to historical vagaries unrelated to quality. Although the coarse shape of violins is integral to their design, details of the body outline can vary without significantly compromising sound quality. What can violin shapes tell us about their makers and history, including the degree that luthiers have influenced each other and the evolution of complex morphologies over time? Here, I provide an analysis of morphological evolution in the violin family, sampling the body shapes of over 9,000 instruments over 400 years of history. Specific shape attributes, which discriminate instruments produced by different luthiers, strongly correlate with historical time. Linear discriminant analysis reveals luthiers who likely copied the outlines of their instruments from others, which historical accounts corroborate. Clustering of averaged violin shapes places luthiers into four major groups, demonstrating a handful of discrete shapes predominate in most instruments. Violin shapes originating from multi-generational luthier families tend to cluster together, and familial origin is a significant explanatory factor of violin shape. Together, the analysis of four centuries of violin shapes demonstrates not only the influence of history and time leading to the modern violin, but widespread imitation and the transmission of design by human relatedness.  相似文献   

3.
Stoel BC  Borman TM 《PloS one》2008,3(7):e2554
Classical violins created by Cremonese masters, such as Antonio Stradivari and Giuseppe Guarneri Del Gesu, have become the benchmark to which the sound of all violins are compared in terms of their abilities of expressiveness and projection. By general consensus, no luthier since that time has been able to replicate the sound quality of these classical instruments. The vibration and sound radiation characteristics of a violin are determined by an instrument's geometry and the material properties of the wood. New test methods allow the non-destructive examination of one of the key material properties, the wood density, at the growth ring level of detail. The densities of five classical and eight modern violins were compared, using computed tomography and specially developed image-processing software. No significant differences were found between the median densities of the modern and the antique violins, however the density difference between wood grains of early and late growth was significantly smaller in the classical Cremonese violins compared with modern violins, in both the top (Spruce) and back (Maple) plates (p = 0.028 and 0.008, respectively). The mean density differential (SE) of the top plates of the modern and classical violins was 274 (26.6) and 183 (11.7) gram/liter. For the back plates, the values were 128 (2.6) and 115 (2.0) gram/liter. These differences in density differentials may reflect similar changes in stiffness distributions, which could directly impact vibrational efficacy or indirectly modify sound radiation via altered damping characteristics. Either of these mechanisms may help explain the acoustical differences between the classical and modern violins.  相似文献   

4.

With greater participation in formal education and increased occupational diversity and mobility, young, cosmopolitan Saraguro musicians in the southern highlands of Ecuador are working to reconstitute their Saraguro Quichua ethnicity in a creative and selective process by which they discard, amplify, and reinvent the aspects of what they perceive to be authentic Saraguro musical culture. Young Saraguro violinists use the bodily movement of performance technique as a key resource with which to reconstitute their ethnicity. Through visual analysis of performance technique and theories of ethnic renewal and bodily movement, I argue that, though older Saraguro violinists sit down low to play their violins, these young Saraguro violinists break from tradition and stand up when they play not only to index their aspirations to do something with their lives other than what tradition and stereotypes dictate for them, but also to index their real opportunities to do so as Saraguros.  相似文献   

5.
How motor skills are stored in the nervous system represents a fundamental question in neuroscience. Although musical motor skills are associated with a variety of adaptations [1-3], it remains unclear how these changes are linked to the known superior motor performance of expert musicians. Here we establish a direct and specific relationship between the functional organization of the corticomuscular system and skilled musical performance. Principal component analysis was used to identify joint correlation patterns in finger movements evoked by transcranial magnetic stimulation over the primary motor cortex while subjects were at rest. Linear combinations of a selected subset of these patterns were used to reconstruct active instrumental playing or grasping movements. Reconstruction quality of instrumental playing was superior in skilled musicians compared to musically untrained subjects, displayed taxonomic specificity for the trained movement repertoire, and correlated with the cumulated long-term training exposure, but not with the recent past training history. In violinists, the reconstruction quality of grasping movements correlated negatively with the long-term training history of violin playing. Our results indicate that experience-dependent motor skills are specifically encoded in the functional organization of the primary motor cortex and its efferent system and are consistent with a model of skill coding by a modular neuronal architecture [4].  相似文献   

6.
The authors presumed that it was possible to replace certain criteria of the expert system aimed at evaluating actual quality of basketball players, proposed by Trnini? et al., with the corresponding indicators of situation-related efficiency (official statistics of the game). Hence, the aim of this study is to verify the potential of establishing such a combined model of expert system that would consist of both the evaluation criteria and certain number of objectively measurable aspects of actual quality (player's partial performance or playing efficiency) and to determine its pragmatic validity. To achieve the aim the sample comprised of 60 basketball players that were competing in the Croatian First Division League in the 1998/99 season was tested. The sample and their quality of play was described by the two different types of data: 1) the 13 situation-related efficiency data (FIBA statistics of the game) utilized to objectively assess performance or playing effectiveness of players, collected at 132 games played by 12 teams, and 2) the evaluation data, subjectively assessing actual quality of players, i.e. their perceived overall performance, collected at the end of the season from the 10 basketball trainers. On the basis of relatively high correlations within the 7 pairs of mutually equivalent variables (from 0.63 to 0.84) and the extremely high correlation (0.97) obtained between the perceived overall performance (actual quality), subjectively assessed with respect to the 19 criteria of the original expert evaluation system, and the overall performance (actual quality) assessed by the combined model (where the 8 evaluation criteria had been replaced by the 7 corresponding indicators ofplaying efficiency), it is feasible to consider the combined model of expert system as an acceptable tool for more objective and economical assessment of actual quality of basketball players.  相似文献   

7.
Natural auditory environment consists of multiple sound sources that are embedded in ambient strong and weak noise. For effective sound communication and signal analysis, animals must somehow extract biologically relevant signals from the inevitable interference of ambient noise. The present study examined how a weak noise may affect the amplitude sensitivity of neurons in the mouse central nucleus of the inferior colliculus (IC) which receives convergent excitatory and inhibitory inputs from both lower and higher auditory centers. Specifically, we studied the amplitude sensitivity of IC neurons using a probe (best frequency pulse) and a masker (weak noise) under simultaneous masking paradigm. For most IC neurons, weak noise masking increases the minimum threshold and decreases the number of impulses. Noise masking also increased the slope and decreased the dynamic range of the rate amplitude function of these IC neurons. The strength of this noise masking was greater at low than at high sound amplitudes. This variation in the amplitude sensitivity of IC neurons in the presence of the weak noise was mostly mediated through GABAergic inhibition. These data indicate that in the real world the ambient weak noise improves amplitude sensitivity of IC neurons through GABAergic inhibition while inevitably decreases the range of overall auditory sensitivity of IC neurons.  相似文献   

8.
When people meet a potential partner for the first time, they are confronted with multiple sources of information, encompassing different modalities, that they can use to determine whether this partner is suitable for them or not. While visual attractiveness has widely been studied with regard to partner choice, olfactory and auditory cues have received less attention, even though they might influence the attitudes that people have towards their partner. Therefore, in this study, we employed a combination of pre-date multimodal rating tasks followed by speed-date sessions. This offered a naturalistic setup to study partner choice and disentangle the relative effects of a priori attractiveness ratings of sight, scent and sound on date success. Visual attractiveness ratings showed a strong positive correlation with propensity to meet the partner again, while the effects of olfactory and auditory attractiveness were negligible or not robust. Furthermore, we found no robust sex differences in the importance of the three modalities. Our findings underscore the relative importance of visual attractiveness in initial mate choice, but do not corroborate the idea that static pre-date measures of auditory and olfactory attractiveness can predict first date outcomes.  相似文献   

9.
The Affordable Care Act set in motion a renewed emphasis on quality of care evaluation. However, the evaluation strategies of quality by the Centers for Medicare and Medicaid Services do not consider geography when comparisons are made among plans. Using an overall measure of a plan’s quality in the public sector—the Medicare Advantage (MA) star ratings—we explored the impact of geography in these ratings. We identified 2,872 U.S counties in 2010. The geographic factor predicted a larger fraction of the MA ratings’ compared to socio-demographic factors which explained less. Also, after the risk adjustments, almost half of the U.S. states changed their ranked position in the star ratings. Further, lower MA star ratings were identified in the Southeastern region. These findings suggest that the geographic component effect on the ratings is not trivial and should be considered in future adjustments of the metric, which may enhance the transparency, accountability, and importantly level the playing field more effectively when comparing quality across health plans.  相似文献   

10.
Human social interactions are regulated by moral norms that define individual obligations and rights. These norms are enforced by punishment of transgressors and reward of followers. Yet, the generality and strength of this drive to punish or reward is unclear, especially when people are not personally involved in the situation and when the actual impact of their sanction is only indirect, i.e., when it diminishes or promotes the social status of the punished or rewarded individual. In a real-life study, we investigated if people are inclined to anonymously punish or reward a person for her past deeds in a different social context. Participants from three socio-professional categories voted anonymously for early career violinists in an important violin competition. We found that participants did not punish an immoral violin candidate, nor did they reward another hyper-moral candidate. On the contrary, one socio-professional category sanctioned hyper-morality. Hence, salient moral information about past behavior did not elicit punishment or reward in an impersonal situation where the impact of the sanction was indirect. We conclude that contextual features play an important role in human motivation to enforce moral norms.  相似文献   

11.
The goal of the research was to define experts opinion about adequate criteria for water polo players' actual quality evaluation and to determine experts opinion about weight coefficients (ponders) of the here defined criteria across the playing positions in the game of water polo. Based upon the expertise performed by ten water polo professionals, the relative importance coefficients with regard to playing positions in the game were determined for twenty seven performance evaluation criteria. High degree of interobserves' agreement was obtained regarding all positions (from 0.93 to 0.96). In concordance with the obtained results the particular playing positions were explicitly described, as well as the similarities and the differences between them were determined from the aspect of the single criteria importance. The research results could be usefully applied by the water polo practitioners for the selection and follow-up of players during training programme implementation, and for programming, control and evaluation of transformational effects.  相似文献   

12.
The phenomena of enhancement and suppression of vibrotactile subjective magnitude were investigated using a matching procedure. Results support earlier reports for audition and vibrotaction suggesting that enhancement is a fundamental sensory process. The time course is described for suppression of stimuli delivered to several different to several different pats of the body. The results are consistent with earlier studies of vibrotactile masking at threshold levels.  相似文献   

13.
尽管大脑听皮层神经元对声音空间信息的编码已有不少的研究报道,但其编码机制并不十分清楚,相关研究在大鼠的初级听皮层也未见详细的研究报道.用神经电生理学方法在大鼠初级听皮层考察了151个听神经元的听空间反应域,分析了神经元对来自不同空间方位声刺激反应的放电数和平均首次发放潜伏期的关系.结果表明,多数(52.32%)神经元对来自对侧听空间的声刺激反应较强,表现为对侧偏好型特征,其他神经元分别归类为同侧偏好型(18.54%)、中间偏好型(18.54%)、全向型(3.31%)和复杂型(7.28%).多数神经元偏好的听空间区域的几何中心位于记录部位对侧听空间的中部和上部.绝大多数初级听皮层神经元对来自偏好听空间的声刺激反应的放电数较多、反应潜伏期较短,对来自非偏好听空间的声刺激反应的放电数较少、反应潜伏期较长,放电数与平均首次发放潜伏期呈显著负相关.在对声音空间信息的编码中,大脑初级听皮层可能综合放电数和潜伏期的信息以实现对声源方位的编码.  相似文献   

14.
In spite of detailed elaboration of masking methods of measuring the frequency selectivity of hearing, such measurements actually are not in use for diagnostics purpose because of their time-consumption and ambiguity of extrapolation of the results to perception of complex sound spectrum patterns. A method of direct measuring of spectrum resolving power using rippled-noise test, is suggested. Results of measurements have shown that the actual ability of hearing to discriminate complex sound spectra is higher than that predicted by acuteness of auditory frequency filters: dependence of acuteness of auditory frequency filters on sound level does not influence the ability to discriminate complex spectra; and the influence on interfering noise on the frequency resolving power can not be explained by a decrease of the spectral contrast by the spread of excitation.  相似文献   

15.
Luan RH  Wu FJ  Jen PH  Sun XD 《生理学报》2005,57(2):225-232
以回声定位蝙蝠为模式动物,采用在体动物细胞外单位记录法,研究了后掩蔽效应对下丘神经元声反应的影响。结果显示,部分神经元(38%,12/31)对测试声刺激的反应明显受到掩蔽声的抑制,其后掩蔽效应强弱与掩蔽声和测试声的相对强度差(inter-stimulus level difference,SLD),以及测试声与掩蔽声之间的间隔时间(inter-stimulus onset asynchrony,SOA)有关:当掩蔽声强度升高或测试声强度降低时,后掩蔽效应增强;而SOA的缩短,亦可见后掩蔽效应增强。另外,相当数量的神经元(52%,16/31)对测试声刺激的反应并不受掩蔽声的影响,其中有的神经元只有在特定SLD和SOA时,才表现出后掩蔽效应。而少数下丘神经元(10%,3/31)在特定SLD和SOA时,掩蔽声对测试声反应有易化作用。上述结果表明,部分下丘神经元参与了声认知活动中的后掩蔽形成过程,推测下丘神经元在定型声反应特性中,对掩蔽声诱导的兴奋前抑制性输入与测试声诱导的兴奋性输入之间的时相性动态整合起关键作用。  相似文献   

16.
Following the futile efforts of generations to reach the high standard of excellence achieved by the luthiers in Cremona, Italy, by variations of design and plate tuning, current interest is being focused on differences in material properties. The long-standing question whether the wood of Stradivari and Guarneri were treated with wood preservative materials could be answered only by the examination of wood specimens from the precious antique instruments. In a recent communication (Nature, 2006), we reported about the degradation of the wood polymers in instruments of Stradivari and Guarneri, which could be explained only by chemical manipulations, possibly by preservatives. The aim of the current work was to identify the minerals from the small samples of the maple wood which were available to us from the antique instruments. The ashes of wood from one violin and one cello by Stradivari, two violins by Guarneri, one viola by H. Jay, one violin by Gand-Bernardel were analyzed and compared with a variety of commercial tone woods. The methods of analysis were the following: back-scattered electron imaging, X-ray fluorescence maps for individual elements, wave-length dispersive spectroscopy, energy dispersive X-ray spectroscopy and quantitative microprobe analysis. All four Cremonese instruments showed the unmistakable signs of chemical treatments in the form of chemicals which are not present in natural woods, such as BaSO4, CaF2, borate, and ZrSiO4. In addition to these, there were also changes in the common wood minerals. Statistical evaluation of 12 minerals by discriminant analysis revealed: a. a difference among all four Cremona instruments, b. the difference of the Cremonese instruments from the French and English antiques, and c. only the Cremonese instruments differed from all commercial woods. These findings may provide the answer why all attempts to recreate the Stradivarius from natural wood have failed. There are many obvious implications with regard to how the green tone wood should be treated, which chould lead to changes in the practice of violin-making. This research should inspire others to analyze more antique violins for their chemical contents.  相似文献   

17.

Background  

In daily life, we are exposed to different sound inputs simultaneously. During neural encoding in the auditory pathway, neural activities elicited by these different sounds interact with each other. In the present study, we investigated neural interactions elicited by masker and amplitude-modulated test stimulus in primary and non-primary human auditory cortex during ipsi-lateral and contra-lateral masking by means of magnetoencephalography (MEG).  相似文献   

18.
In the animal facility, a range of different sounds are present. On the one hand, rats and humans will regard sound and noise differently even within the audible range, but on the other hand mice and rats being very adaptable to the environment may adapt to living in a noisy facility with e.g. a radio playing. It was the aim of the present study to investigate whether two different strains of rats had different preferences for different kinds of sound patterns, including radio, and to get an indication of whether they are able to distinguish between different sound patterns. The present preference study revealed that rats were able to distinguish between different sound patterns. They showed a clear preference for silence to anything else, which may be taken as an indication that they feel disturbed by the sound from the speaker.  相似文献   

19.
Main tendencies in studying of human and animals auditory system with psychoacoustical and electrophysiologycal methods are considered. Concerning psychoacoustical studies some basic data are presented as well as contemporary tendencies in hearing physiology in analysis of the intensity, frequency, temporal characteristics of the sound signals and data related to such phenomena as masking and adaptation. Data concerning directional hearing are presented in detail as a basis of auditory virtual reality. In electrophysiological studies of the auditory system detailed analysis of mapping in auditory centers and mechanisms concerning localization of unmoved and moving auditory stimuli was performed. Special attempt was paid to consider the reflection of different types of auditory signals in human evoked potentials.  相似文献   

20.
The shape of female mate preference functions influences the speed and direction of sexual signal evolution. However, the expression of female preferences is modulated by interactions between environmental conditions and the female's sensory processing system. Noise is an especially relevant environmental condition because it interferes directly with the neural processing of signals. Although noise is therefore likely a significant force in the evolution of communication systems, little is known about its effects on preference function shape. In the grasshopper Chorthippus biguttulus, female preferences for male calling song characteristics are likely to be affected by noise because its auditory system is sensitive to fine temporal details of songs. We measured female preference functions for variation in male song characteristics in several levels of masking noise and found strong effects of noise on preference function shape. The overall responsiveness to signals in noise generally decreased. Preference strength increased for some signal characteristics and decreased for others, largely corresponding to expectations based on neurophysiological studies of acoustic signal processing. These results suggest that different signal characteristics will be favored under different noise conditions, and thus that signal evolution may proceed differently depending on the extent and temporal patterning of environmental noise.  相似文献   

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