Infant Auditory Temporal Acuity: Gap Detection     

Lynne A. Werner  G. Cameron Marean  Christopher F. Halpin  Naney Benson Spetner  Jay M. Gillenwater 《Child development》1992,63(2):260-272

The development of auditory temporal acuity during infancy was examined in 3-, 6-, and 12-month-old infants and in adults using the gap detection paradigm. Listeners detected a series of gaps, or silent intervals, or variable duration in a broadband noise. In order to vary the acoustic frequencies available to the listener, a high-pass noise was used to mask frequencies above specified cutoffs. High-pass maskers with cutoffs of 500, 2,000, and 8,000 Hz were used. The minimum detectable gap was determined using the Observer-based Psychoacoustic Procedure. The thresholds of 3- and 6-month-olds were considerably poorer than those of the adults, although the effect of masker condition was about the same for these 3 groups. The thresholds of 12-month-olds were significantly worse than the adults when the stimulus was unmasked or when the masker cutoff frequency was 2,000 or 8,000 Hz. When the masker cutoff frequency was 500 Hz, 12-month-olds fell into 2 groups: some had gap thresholds that were about the same as 3- and 6-month-olds, while some had gap thresholds that approached those of adults. In a second experiment, a larger group of 12-month-olds were tested with a 500-Hz masker cutoff. Average performance of 12-month-olds was about the same as that of 3- and 6-month-olds in Experiment 1. Some infants attained thresholds close to those of adults. Thus, gap detection thresholds are quite poor in infants, although the similarity of the effect of frequency on performance in infants and adults suggests that the mechanisms governing temporal resolution in infants operate qualitatively like those in adults.  相似文献   

Buchbesprechungen     

Werner Hauser  Peter Reininghaus  Beatrix Schwar 《Zeitschrift für Hochschulrecht, Hochschulmanagement und Hochschulpolitik: zfhr》2007,6(4):131-134

Ohne Zusammenfassung  相似文献   

ICMI Study 14: Applications and modelling in mathematics education – Discussion document     

Werner Blum 《Educational Studies in Mathematics》2002,51(1-2):149-171

This paper is the Discussion Documentfor a forthcoming ICMI Study on Applications and Modelling in MathematicsEducation. As will be well-known, fromtime to time ICMI (the InternationalCommission on Mathematical Instruction)mounts specific studies in order toinvestigate, both in depth and in detail,particular fields of interest inmathematics education. The purpose of thisDiscussion Document is to raise someimportant issues related to the theory andpractice of teaching and learningmathematical modelling and applications,and in particular to stimulate reactionsand contributions to these issues and tothe topic of applications and modelling asa whole (see Section 4). Based onthese reactions and contributions, alimited number (approximately 75) ofparticipants will be invited to aconference (the Study Conference)which is to take place in February 2004 inDortmund (Germany). Finally, using thecontributions to this conference, a bookwill be produced (the Study Volume)whose content will reflect thestate-of-the-art in the topic ofapplications and modelling in mathematicseducation and suggest directions for futuredevelopments in research and practice.The authors of this Discussion Document are themembers of the International ProgrammeCommittee for this ICMI Study. Thecommittee consists of 14 people from 12countries, listed at the end of Section4. The structure of the Document isas follows. In Section 1, we identifysome reasons why it seems appropriate tohold a study on applications and modelling.Section 2 sets a conceptual frameworkfor the theme of this Study, and Section3 contains a selection of importantissues, challenges and questions related tothis theme. In Section 4 we describepossible modes and ways of reacting to theDiscussion Document, and in the finalSection 5 we provide a shortbibliography relevant to the theme of thisStudy. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

The 2012 Acquisitions Institute at Timberline Lodge     

Andrea A. Wirth 《资料收集管理》2013,38(1):67-74

This year the Acquisitions Institute was held May 19 through May 22, 2012, and brought together approximately eighty people from around the country. Seventeen presentations on acquisitions, collection development, and collection management were delivered over two days, with breaks, meals, and optional fun events providing ample opportunity to socialize and network. Written by a first-time attendee, this article describes the sessions of the 2012 institute.  相似文献   

ticTOCs: A New Service for “Keeping Current”     

Andrea A. Wirth 《资料收集管理》2013,38(3):229-233

ticTOCs, a new journal table of contents service, provides users a free resource for managing RSS feeds for new content from selected journals. This service could be used as a complement and in some cases as an alternative to other table of contents providers. Using RSS feeds provided by publishers, ticTOCs provides an easy-to-use interface for finding, viewing, and saving current tables of contents. The service also provides OPML (Outline Processor Markup Language) file exports so that users can incorporate the feeds they find in ticTOCs into a feed reader of their choice.  相似文献   

Trends and changes in the classification of children’s books in West Germany     

Werner Jahrmann 《International Information and Library Review》2013,45(3):339-342

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Household‐level demand for cable television: A probit analysis.     

Michael O. Wirth  Harry Bloch 《Journal of Media Economics》2013,26(2):21-34

The authors explore demand for cable services in individual households and find that the quality of over‐the‐air reception, interest in nonprogramming entertainment services, and service quality directly affect that demand. The study also explores demographic and behavioral differences in demand for basic and pay services and outlines their implications for cable systems operators.  相似文献   

Cable's economic impact on over‐the‐air broadcasting     

Michael O. Wirth 《Journal of Media Economics》2013,26(2):39-53

The author argues that cable industry is having increasingly negative impact on broadcast television as its power in both the programing and advertising markets increase. Cable system operaters are having increasing incentives to drop or refuse to add broadcast stations or to relocate them to less desirable channel locations as a means of improving their performance in the markets. The author warns that current trends could be harmful to many broadcast stations, but he is especially pessimistic about the future of independent UHF stations.  相似文献   

College Student Success: A Qualitative Modeling Approach     

Ralph Mario Wirth  Raymond V. Padilla 《Community College Journal of Research & Practice》2013,37(9):688-711

This qualitative study highlighted student perspectives on barriers to success at a community college located in a south Texas city. The study examined barriers to student success, the knowledge that successful students possess to overcome the barriers, and the actions that successful students undertake to overcome the barriers. Padilla's (2004 Padilla , R. V. ( 1999 ). College student retention: Focus on success . Journal of College Student Retention , 1 ( 2 ), 131 – 145 .[Crossref] , [Google Scholar]) theoretical framework and methods for modeling student success provided the conceptual framework for the study. The data analysis resulted in the development of a local student success model and an implementation model for student services at the subject campus.  相似文献   

Increase of Total Body Water With Decrease of Body Mass While Running 100 km Nonstop—Formation of Edema?     

Beat Knechtle  Andrea Wirth  Patrizia Knechtle  Thomas Rosemann 《Research quarterly for exercise and sport》2013,84(3):593-603

We investigated whether ultraendurance runners in a 100-km run suffer a decrease of body mass and whether this loss consists of fat mass, skeletal muscle mass, or total body water. Male ultrarunners were measured pre- and postrace to determine body mass, fat mass, and skeletal muscle mass by using the anthropometric method. In addition, bioelectrical impedance analysis was used to determine total body water, and urinary (urinary specific gravity) and hematological parameters (hematocrit and plasma sodium) were measured in order to determine hydration status. Body mass decreased by 1.6 kg (p < .01), fat mass by 0.4 kg (p < .01), and skeletal muscle mass by 0.7 kg (p < .01), whereas total body water increased by 0.8 L (p < .05). Hematocrit and plasma sodium decreased significantly (p < .01), whereas plasma urea and urinary specific gravity (USG) increased significantly (p < .01). The decrease of 2.2% body mass and a USG of 1.020 refer to a minimal dehydration. Our athletes seem to have been relatively overhydrated (increase in total body water and plasma sodium) and dehydrated (decrease in body mass and increase in USG) during the race, as evidenced by the increased total body water and the fact that plasma sodium and hematocrit were lower postrace than prerace. The change of body mass was associated with the change of total body water (p < .05), and we presume the development of  相似文献