Integrated stratigraphy of the Waitakian-Otaian Stage boundary stratotype, Early Miocene, New Zealand

The base of the type section of the Otaian Stage at Bluecliffs, South Canterbury, is recognised as the stratotype for the boundary between the Waitakian and Otaian Stages. Principal problems with the boundary are the restriction of existing bioevent proxies to shelf and upper slope environments and its uncertain age. These topics are addressed by a multidisplinary study of a 125 m section about the boundary, which examines its lithostratigraphy, depositional setting, biostratigraphy, correlation, and geochronology. The lower siltstone lithofacies (0-38.5 m) was deposited at upper bathyal depths (200-600 m) in a marginal basin which was partially sheltered from fully oceanic circulation by a submarine high and islands. The site was covered by cool-temperate water and was probably adjacent to the Subtropical Convergence. This unit is succeeded by the banded lithofacies (38.5-106 m) and the upper siltstone lithofacies (basal 19 m studied). Paleodepth probably declined up-sequence, but deposition at shelf depths is not definitely indicated. A cyclic pattern of abundance spikes in benthic and planktonic foraminifera commences 9 m above base and extends to 73 m in the banded lithofacies. Oxygen isotope excursions (up to 2.08%) in Euuvigerina miozea and Cibicides novozelandicus are greatest within the interval containing the abundance spikes. The stage boundary occurs in the banded lithofacies at the highest abundance spike (73 m). Although condensed intervals might affect the completeness of the section, they are not associated with sedimentary discontinuities, and we consider that the section is suitable as a biostratigraphic reference. Spores, pollens, dinoflagellates, calcareous nannofossils, foraminifera, bryozoans, and ostracods are preserved near the boundary, but molluscs principally occur higher, in the shallower upper siltstone lithofacies. Siliceous microfossils are rare. There is considerable scope for further biostratigraphic research. The primary event marking the boundary at 73 m is the appearance of the benthic foraminifer Ehrenbergina marwicki. This is a distinctive and widely distributed event but is restricted to shelf and upper bathyal environments. Supplementary events in planktonic foraminifera and calcareous nannofossils were researched. Highest occurrences of Globigerina brazieri and G. euapertura are recorded at 47 and 58 m. There is a marked decline in relative abundance of Paragloborotalia spp. at 62 m. Helicosphaera carteri becomes more abundant than H. euphratis between 56 and 87 m. These events are not exact proxies for the boundary but they may usefully indicate proximity to it. They occur in the interval of prominent spikes in foraminiferal abundance. The Waitakian-Otaian boundary is dated at 21.7 Ma by strontium isotopes. Stable primary remanence could not be determined in a pilot paleomagnetic study of Bluecliffs specimens. However, specimens trended towards reversed polarity, and remagnetisation great circle analysis will allow directions to be calculated in future collections

Acoustic Signs of Supraglottal Constriction in Pathological Voices

Purpose: This study aims to identify the acoustic signs of supraglottal constriction and effects of some vocal manipulation techniques. It is hypothesized that some task-related acoustic contrasts would differ between voice patients with and without supraglottal constriction due to different vocal tract configurations. Method: Classified through videostroboscopic examinations, 30 participants were gender and age-matched to form two comparison groups (“constricted” and “non-constricted”), with five males and ten females in each group. Participants were asked to sustain a vowel (/a/ or /i/) for approximately three seconds in five tasks, including normal-pitch, low-pitch, high-pitch, /m/-onset (i.e., with the consonant /m/ preceding the vowel at normal pitch), and /h/-onset tasks. Acoustic signals were analyzed to extract measures from the mid-portion of the vowel. Results: The “constricted” group showed a lack of task-related contrasts on signal-to-noise ratio, singing power ratio, frequency of the second formant, and the amplitude difference between the first formant and the first harmonic. Conclusion: Further investigations are needed to assess the predictive power of the proposed task-based acoustic approach for detecting supraglottal constriction

A. Balmin

DB2 XML is a hybrid database system that combines the relational capabilities of DB2 Universal Databasee (UDB) with comprehensive native XML support. DB2 XML augments DB2t UDB with a native XML store, XML indexes, and query processing capabilities for both XQuery and SQL/XML that are integrated with those of SQL. This paper presents the extensions made to the DB2 UDB compiler, and especially its costbased query optimizer, to support XQuery and SQL/XML queries, using much of the same infrastructure developed for relational data queried by SQL. It describes the challenges to the relational infrastructure that supporting XQuery and SQL/XML poses and provides the rationale for the extensions that were made to the three main parts of the optimizer: the plan operators, the cardinality and cost model, and statistics collection