bluuebunny/crossref_metadata_2025_split huggingface dataset:
Possible uses of submarine canyons in acoustic thermometry
Authors: Denner Warren W. , Lashkari Khosrow , Miller James H. , Chiu Ching-Sang 
Published: October 2005

High-power sources and high-gain receivers are used in long-range ocean acoustic thermometry. Because of power supply and data telemetry the sources and receivers are often placed near coastal facilities. There may be some significant benefits associated with taking advantage of natural terrain features to protect the sources and receivers from fisheries, and to optimize certain aspects of their performance. Sources and receivers are generally moored in deep water, in the axis of the sound channel, on the order of 100 to 1000 m. The shortest distance from shore to deep water is frequently associated with submarine canyons. For example it is less than 15 km from Point Pinos to water depths in excess of 2000 m in Monterey Submarine Canyon, less than half the distance along continental borders without submarine canyons. Fishermen do not fish inside the canyon walls for fear of rapid depth changes. Therefore, the canyons provide a natural barrier to the threat of fishing activity to moored sources and receivers. It is obvious that the canyon restricts the ray paths between a source or receiver in the canyon. However, if the source and receiver geometry is carefully selected this may not be a significant limitation. Oceanic noise arrivals in a submarine canyon can be restricted to those in the direction of deep water. If for example the canyon opens at an angle of 30 deg from the receiver and if the noise is omnidirectional at the axis of the array, the terrain barrier restricts noise to that 30-deg window.
This would provide an optimum noise reduction of 7.8 dB. On the source side of the problem, placing the source in the canyon will limit the high-intensity blast to the energy going out the canyon mouth into deep water. In this way, marine mammals in the area of the source would be shielded from the direct blast unless they happen to be in a restricted direction from the source, or very near the source. If the source could be made so that it was directional, the volume of the direct blast would be even more restricted. Certainly, there are some possible downsides to placing sources and receivers in submarine canyons. These will be explored in the presentation.
Electric micromotors on silicon
Authors: Mehregany Mehran 
Published: October 2005

A review of micromotor technology will be presented and micromotor design, fabrication, and operational characteristics will be discussed. Micromotors are submillimeter actuators capable of unrestrained motion in at least one degree of freedom. The micromotors described in this presentation are actuated by attractive electrostatic forces. For micromotor fabrication, silicon surface micromachining is used to create freely moving parts held to the surface of the silicon wafer with bearings. In this process, heavily phosphorus-doped polysilicon is used for the structural parts, deposited silicon dioxide is used for the scarificial layers, and silicon-rich silicon nitride is used for electrical isolation. Layers of the structural and sacrificial materials are deposited and patterned in a manner that the structural polysilicon parts (e.g., the rotor) are appropriately encapsulated by the sacrificial oxide layers. At the final stage of fabrication, the sacrificial oxide is selectively removed in hydrofluoric acid to free the micromotor structural parts. Operational rotary, variable-capacitance, salient-pole, and harmonic (or wobble) side-drive micromotors have been fabricated with two different bearing designs and typical diameters of 100- to 130-μm, rotor/stator gaps of 1.5 μm, and a rotor thickness of 2.2 μm. Electrical operation of the salient-pole and harmonic side-drive micromotors have been demonstrated in a number of gaseous environments including room air, oxygen, argon, and nitrogen, and in insulating liquids such as silicone lubricating oil and deionized water.
Minimum operating voltages differ with the environment but can be as low as 30 V. Extended operation (i.e., beyond 100 h) of the micromotors in gaseous environments and in silicone lubricating oil has been demonstrated. Operational speeds of up to 15 000 and 1000 rpm have been achieved in gaseous environments for the salient-pole and harmonic side-drive micromotors, respectively. In silicone lubricating oil, the maximum operation speed has been below 125 rpm for both micromotor types. [The presentation reflects the results of a collaborative micromotor research program with Professor J. H. Lang and Professor S. D. Senturia of MIT. This research program is funded by the National Science Foundation.]
Internal phonetic category structure depends on multiple acoustic properties: Evidence for within-category trading relations
Authors: Hodgson Philip , Miller Joanne L. 
Published: October 2005

Two acoustic properties underlying the distinction between the presence and absence of a stop consonant, as in say vs stay, are silence duration and first-formant (F1) onset frequency: little or no silence and a high F1 onset frequency specify say, whereas a longer silence and a lower F1 onset frequency specify stay. Previous research has established that these two properties enter into a trading relation at the phonetic category boundary. Whether they also enter into a trading relation within the category is explored in the current investigation. Two series of stimuli having low (230 Hz) and high (430 Hz) F1 onset frequencies, respectively, have been created. Silence duration in each series varied from 0 to 996 ms, resulting in stimuli ranging from say through stay to an exaggerated version of stay. A preliminary two-choice study (with just the stimuli between 0 and 136 ms) confirmed the expected trading relation at the say–stay boundary, with the boundary for the high F1 series being located at a longer silence duration than that for the low F1 series. In the main experiment, listeners were presented randomizations of all the stimuli and asked to judge each for its goodness as an exemplar of the word stay, using a rating scale (1–10). It was expected that for each series, only a limited range of stimuli would be given high ratings. At issue was the location of these stimuli. If silence duration and F1 onset frequency trade within the category as well as at the boundary, then the best exemplars for the high F1 series should be displaced towards longer silence durations relative to those for the low F1 series.
The results confirmed the predictions. These findings indicate that the internal structure of phonetic categories is determined by multiple acoustic properties. It is suggested that this complex acoustic-phonetic mapping derives from the common articulatory origin of these properties. [Work supported by NIH.]
Dipole logging in cased boreholes
Authors: Schmitt Denis P. 
Published: October 2005

Shear wave logging through casing can be challenging, especially when the surrounding formation is unconsolidated. This study identifies two possible causes of the problem using synthetic microseismograms, dispersion curves, signal processing scheme based on Prony’s method, and frequency-dependent sensitivity coefficients with respect to the layers’ parameters. The first possible cause is eccentering of the tool when the cased hole is well bonded. The second possible cause is poor bonding, which is modeled by the presence of fluid annulus. An off-center dipole source located in a well-bonded cased hole generates a Stoneley wave that is poorly coupled to the surrounding formation and propagates at a velocity close to the compressional velocity of the borefluid. This Stoneley wave can obscure the formation shear wave signal associated with a slow (unconsolidated) formation. In a vertical well-bonded cased hole, shear wave logging slow (unconsolidated) formations can be reliably performed despite the leaky character of the flexural mode if the tool is well centralized, and a low-source frequency (around 2 kHz) is used. In a highly deviated or horizontal well, where the tool cannot be efficiently centralized, reliable measurements can still be obtained provided the directivities of the source and receivers are perpendicular to the direction of eccentricity. In poorly bonded cased holes, a dipole tool, regardless of its position, excites supplementary low-velocity modes that are associated with vibrations of the steel casing and the presence of an external fluid annulus. The maximum excitation of these modes is located in the low-frequency region, similar to that of unconsolidated formation signals. When the cement is not bonded to the casing, depending on the thickness of the fluid annulus, an unconsolidated formation signal may be corrupted, regardless of the tool’s position within the borehole. The Stoneley wave generated by the off-center source is overpowered by the annulus mode. Even when no interference occurs, the supplementary mode exhibits high, low-frequency energy due to a strong low-frequency coupling with the casing which causes the formation signal to be weak, regardless of the type of formation (fast or slow).
As a consequence, the source must be powerful and the recording system must have a large dynamic range for the formation signal to be reliably detected. When the cement is well bonded to the casing but not to the formation, the effects of the presence of the annulus mode are less drastic.
Measuring the strength of auditory fusion for synchronously and nonsynchronously fluctuating narrow-band noise pairs
Authors: Rappold Patrick W. , Mendoza Lee , Collins M. Jane 
Published: October 2005

This experiment examines the ‘‘strength’’ of auditory fusion for narrow-band noise pairs. Each pair of noise bands consisted of a target band and a flanker band presented simultaneously. The temporal envelopes of the noise bands within a pair fluctuated either in synchrony (synchronous condition) or not in synchrony (nonsynchronous condition). Each noise-band pair was alternated rapidly with a noise band (captor band) presented alone. The duration of the silent period between a noise-band pair and a captor band [i.e., onset-to-onset interval (OTO)] was decreased by listeners until auditory fusion of the pair was disrupted by capturing the target band into a sequential-stream with the captor band.
Results showed that listeners required significantly shorter OTOs to capture the target bands from the synchronous pairs than from the nonsynchronous pairs, suggesting that strength of auditory fusion was greater for the noise bands that fluctuated in synchrony than for those that did not. The results of this experiment are discussed relative to hypotheses based on auditory stream segregation to explain auditory phenomena such as comodulation detection difference, modulation detection interference, and comodulation masking release.
Measures of auditory brain-stem responses, distortion product otoacoustic emissions, hair cell loss, and forward masked tuning curves in the waltzing guinea pig
Authors: Canlon Barbara , Marklund Kasper , Borg Erik 
Published: October 2005

Measures of the auditory brain-stem response (ABR), distortion product otoacoustic emission (2f1−f2), hair cell loss, and forward masked tuning curves were obtained from waltzing guinea pigs and their age-matched controls at postnatal day 2, 9, 15, and 30. A mild ABR threshold shift (10–15 dB) is seen by 2 days postnatal and gradually increases to a more severe threshold shift (40–50 dB) by postnatal day 15. Already by 30 days the auditory brain-stem response, being beyond the output of the instrumentation, could not be elicited. The mean distortion product otoacoustic emission (DPOE) amplitude as a function of f1 amplitude for the postnatal day 2, 9, and 15 waltzing guinea pigs were only between 3 and 8 dB below the control values for stimulus levels below 65 dB SPL. The DPOE audiogram constructed for the waltzing guinea pigs shows no more than an 8-dB mean difference from the control values when the intensity of f1 was 50 dB SPL, and no more than 10 dB when f1 was 60 dB SPL. Analysis of the individual cases revealed that the DPOE amplitude could be greater than control values. On the contrary, when f1 stimulus levels were below 65 dB SPL, DPOEs could not be detected for the postnatal day 30 waltzing guinea pigs. At stimulus levels above 65 dB SPL, DPOEs could be recorded yet these responses were depressed from control values by 10 to 25 dB. Analysis of surface preparations of the organ of Corti from the day 15 waltzing guinea pig reveals that the prominent alteration occurs on the third row outer hair cells.
To a lesser extent, the second row outer hair cells, and then the first row outer hair cells are affected while the inner hair cells appear normal. In contrast, the organ of Corti from the postnatal day 30 waltzing guinea pig showed a more extensive outer hair cell loss among all three rows as well as a considerable degree of inner hair cell loss. Forward masked auditory brain-stem response tuning curves were generated at 8, 4, and 1 kHz for control and waltzing guinea pigs between 2 and 12 days of age. All tuning curves obtained from waltzing guinea pigs showed progressive decreases in sensitivity with increasing age. The Q 10 dB values of the 1- and 4-kHz tuning curves were not different between the controls and the waltzing guinea pigs at any age. However, compared to the controls, the Q 10-dB values of the 8-kHz tuning curves were reduced by 50% for the waltzing guinea pigs.
Current and Developing Technologies for Monitoring Agents of Bioterrorism and Biowarfare
Authors: Lim Daniel V. , Simpson Joyce M. , Kearns Elizabeth A. , Kramer Marianne F. 
Published: October 2005

SUMMARYRecent events have made public health officials acutely aware of the importance of rapidly and accurately detecting acts of bioterrorism. Because bioterrorism is difficult to predict or prevent, reliable platforms to rapidly detect and identify biothreat agents are important to minimize the spread of these agents and to protect the public health. These platforms must not only be sensitive and specific, but must also be able to accurately detect a variety of pathogens, including modified or previously uncharacterized agents, directly from complex sample matrices. Various commercial tests utilizing biochemical, immunological, nucleic acid, and bioluminescence procedures are currently available to identify biological threat agents. Newer tests have also been developed to identify such agents using aptamers, biochips, evanescent wave biosensors, cantilevers, living cells, and other innovative technologies. This review describes these current and developing technologies and considers challenges to rapid, accurate detection of biothreat agents. Although there is no ideal platform, many of these technologies have proved invaluable for the detection and identification of biothreat agents.
Extended-Spectrum β-Lactamases: a Clinical Update
Authors: Paterson David L. , Bonomo Robert A. 
Published: October 2005

SUMMARYExtended-spectrum β-lactamases (ESBLs) are a rapidly evolving group of β-lactamases which share the ability to hydrolyze third-generation cephalosporins and aztreonam yet are inhibited by clavulanic acid. Typically, they derive from genes for TEM-1, TEM-2, or SHV-1 by mutations that alter the amino acid configuration around the active site of these β-lactamases. This extends the spectrum of β-lactam antibiotics susceptible to hydrolysis by these enzymes. An increasing number of ESBLs not of TEM or SHV lineage have recently been described. The presence of ESBLs carries tremendous clinical significance. The ESBLs are frequently plasmid encoded. Plasmids responsible for ESBL production frequently carry genes encoding resistance to other drug classes (for example, aminoglycosides). Therefore, antibiotic options in the treatment of ESBL-producing organisms are extremely limited. Carbapenems are the treatment of choice for serious infections due to ESBL-producing organisms, yet carbapenem-resistant isolates have recently been reported. ESBL-producing organisms may appear susceptible to some extended-spectrum cephalosporins. However, treatment with such antibiotics has been associated with high failure rates. There is substantial debate as to the optimal method to prevent this occurrence. It has been proposed that cephalosporin breakpoints for theEnterobacteriaceaeshould be altered so that the need for ESBL detection would be obviated. At present, however, organizations such as the Clinical and Laboratory Standards Institute (formerly the National Committee for Clinical Laboratory Standards) provide guidelines for the detection of ESBLs in klebsiellae andEscherichia coli. In common to all ESBL detection methods is the general principle that the activity of extended-spectrum cephalosporins against ESBL-producing organisms will be enhanced by the presence of clavulanic acid. ESBLs represent an impressive example of the ability of gram-negative bacteria to develop new antibiotic resistance mechanisms in the face of the introduction of new antimicrobial agents.
Baylisascariasis
Authors: Gavin Patrick J. , Kazacos Kevin R. , Shulman Stanford T. 
Published: October 2005

SUMMARYThe raccoon roundworm,Baylisascaris procyonis, is the most common and widespread cause of clinical larva migrans in animals. In addition, it is increasingly recognized as a cause of devastating or fatal neural larva migrans in infants and young children and ocular larva migrans in adults. Humans become infected by accidentally ingesting infectiveB. procyoniseggs from raccoon latrines or articles contaminated with their feces. Two features distinguishB. procyonisfrom other helminthes that cause larva migrans: (i) its aggressive somatic migration and invasion of the central nervous system and (ii) the continued growth of larvae to a large size within the central nervous system. Typically,B. procyonisneural larva migrans presents as acute fulminant eosinophilic meningoencephalitis. Once invasion of the central nervous system has occurred, the prognosis is grave with or without treatment. To date, despite anthelmintic treatment of cases ofB. procyonisneural larva migrans, there are no documented neurologically intact survivors. Epidemiologic study of human cases of neural larva migrans demonstrate that contact with raccoon feces or an environment contaminated by infective eggs and geophagia or pica are the most important risk factors for infection. In many regions of the United States, increasingly large populations of raccoons, with high rates ofB. procyonisinfection, live in close proximity to humans. Although documented cases of human baylisascariasis remain relatively uncommon, widespread contamination of the domestic environment by infected raccoons suggests that the risk of exposure and human infection is probably substantial. In the absence of early diagnosis or effective treatment, prevention of infection is the most important public health measure.
Mycoplasmas and Ureaplasmas as Neonatal Pathogens
Authors: Waites Ken B. , Katz Brenda , Schelonka Robert L. 
Published: October 2005

SUMMARYThe genital mycoplasmas represent a complex and unique group of microorganisms that have been associated with a wide array of infectious diseases in adults and infants. The lack of conclusive knowledge regarding the pathogenic potential ofMycoplasmaandUreaplasmaspp. in many conditions is due to a general unfamiliarity of physicians and microbiology laboratories with their fastidious growth requirements, leading to difficulty in their detection; their high prevalence in healthy persons; the poor design of research studies attempting to base association with disease on the mere presence of the organisms in the lower urogenital tract; the failure to consider multifactorial aspects of diseases; and considering these genital mycoplasmas only as a last resort. The situation is now changing because of a greater appreciation of the genital mycoplasmas as perinatal pathogens and improvements in laboratory detection, particularly with regard to the development of powerful molecular nucleic acid amplification tests. This review summarizes the epidemiology of genital mycoplasmas as causes of neonatal infections and premature birth; evidence linking ureaplasmas with bronchopulmonary dysplasia; recent changes in the taxonomy of the genusUreaplasma; the neonatal host response to mycoplasma and ureaplasma infections; advances in laboratory detection, including molecular methods; and therapeutic considerations for treatment of systemic diseases.
NON-UNIQUENESS AND RADIUS OF CYCLIC UNARY NFAs
Authors: DOMARATZKI MICHAEL , ELLUL KEITH , SHALLIT JEFFREY , WANG MING-WEI 
Published: October 2005

In this paper we study some properties of cyclic unary regular languages. We find a connection between the uniqueness of the minimal NFA for certain cyclic unary regular languages and a Diophantine equation studied by Sylvester. We also obtain some results on the radius of unary languages. We show that the nondeterministic radius of a cyclic unary regular language L is not necessarily obtained by any of the minimal NFAs for L. We give a class of examples which demonstrates that the nondeterministic radius of a regular language cannot necessarily even be approximated by the minimal radius of its minimal NFAs.
Reading Derrida's New Testament: A Critical Appraisal
Authors: Twomey Jay 
Published: October 2005

AbstractDerrida is a source of profound inspiration for many scholars in recent New Testament studies. He makes available a variety of critical tools with which to examine the fissures and rough edges of the New Testament texts, not (as with source and form critics) in order to reconstitute their origins and original meanings, but rather in recognition of the indeterminacies which constitute the texts themselves. Given his growing importance to the field, however, it is surprising to note that Derrida's own readings of the New Testament often fail to exemplify even the most basic possibilities that deconstruction has to offer. In his hands, the New Testament can take on a surprising resistance to deconstructive critique. This essay is primarily an effort at encouraging New Testament scholars (who clearly can out-Derrida Derrida with regard to the New Testament) to return to Derrida's readings of certain New Testament texts with a fresh, critical eye. It examines a number of Derrida's New Testament interventions, and in the process shows (a) the ways in which his reading of the texts is at odds with the critical project within which it is embedded, and (b) what a more adequately deconstructive reading of the same texts might look like. The article concludes with a complex of tentative thoughts on why Derrida's readings of the New Testament can seem so inadequately Derridean.