Coding of sound direction in the auditory periphery of the lake sturgeon, Acipenser fulvescens

The lake sturgeon, Acipenser fulvescens, belongs to one of the few extant nonteleost ray-finned fishes and diverged from the main vertebrate lineage about 250 million years ago. The aim of this study was to use this species to explore the peripheral neural coding strategies for sound direction and compare these results to modern bony fishes (teleosts). Extracellular recordings were made from afferent neurons innervating the saccule and lagena of the inner ear while the fish was stimulated using a shaker system. Afferents were highly directional and strongly phase locked to the stimulus. Directional response profiles resembled cosine functions, and directional preferences occurred at a wide range of stimulus intensities (spanning at least 60 dB re 1 nm displacement). Seventy-six percent of afferents were directionally selective for stimuli in the vertical plane near 90° (up down) and did not respond to horizontal stimulation. Sixty-two percent of afferents responsive to horizontal stimulation had their best axis in azimuths near 0° (front back). These findings suggest that in the lake sturgeon, in contrast to teleosts, the saccule and lagena may convey more limited information about the direction of a sound source, raising the possibility that this species uses a different mechanism for localizing sound. For azimuth, a mechanism could involve the utricle or perhaps the computation of arrival time differences. For elevation, behavioral strategies such as directing the head to maximize input to the area of best sensitivity may be used. Alternatively, the lake sturgeon may have a more limited ability for sound source localization compared with teleosts.

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Spatial tuning to sound-source azimuth in the inferior colliculus of unanesthetized rabbit

Journal of Neurophysiology ◽

10.1152/jn.00532.2011 ◽

2011 ◽

Vol 106 (5) ◽

pp. 2698-2708 ◽

Cited By ~ 9

Author(s):

Shigeyuki Kuwada ◽

Brian Bishop ◽

Caitlin Alex ◽

Daniel W. Condit ◽

Duck O. Kim

Keyword(s):

Inferior Colliculus ◽

Sound Source ◽

Neural Coding ◽

Full Range ◽

Sound Field ◽

Stimulus Level ◽

Unanesthetized Rabbit ◽

Binaural Stimulation ◽

Wide Range ◽

Contralateral Ear

Despite decades of research devoted to the study of inferior colliculus (IC) neurons' tuning to sound-source azimuth, there remain many unanswered questions because no previous study has examined azimuth tuning over a full range of 360° azimuths at a wide range of stimulus levels in an unanesthetized preparation. Furthermore, a comparison of azimuth tuning to binaural and contralateral ear stimulation over ranges of full azimuths and widely varying stimulus levels has not previously been reported. To fill this void, we have conducted a study of azimuth tuning in the IC of the unanesthetized rabbit over a 300° range of azimuths at stimulus levels of 10–50 dB above neural threshold to both binaural and contralateral ear stimulation using virtual auditory space stimuli. This study provides systematic evidence for neural coding of azimuth. We found the following: 1) level-tolerant azimuth tuning was observed in the top 35% regarding vector strength and in the top 15% regarding vector angle of IC neurons; 2) preserved azimuth tuning to binaural stimulation at high stimulus levels was created as a consequence of binaural facilitation in the contralateral sound field and binaural suppression in the ipsilateral sound field; 3) the direction of azimuth tuning to binaural stimulation was primarily in the contralateral sound field, and its center shifted laterally toward −90° with increasing stimulus level; 4) at 10 dB, azimuth tuning to binaural and contralateral stimulation was similar, indicating that it was mediated by monaural mechanisms; and 5) at higher stimulus levels, azimuth tuning to contralateral ear stimulation was severely degraded. These findings form a foundation for understanding neural mechanisms of localizing sound-source azimuth.

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Peripheral neural coding strategies for spectral analysis and sound source location in the nonteleost bony fish, Acipenser fulvescens.

The Journal of the Acoustical Society of America ◽

10.1121/1.4783404 ◽

2009 ◽

Vol 125 (4) ◽

pp. 2506-2506

Author(s):

Michaela Meyer ◽

Arthur N. Popper ◽

Richard R. Fay

Keyword(s):

Spectral Analysis ◽

Sound Source ◽

Neural Coding ◽

Source Location ◽

Bony Fish ◽

Acipenser Fulvescens ◽

Coding Strategies

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Read, Understand, Learn, & Excel: Development and Testing of an Automated Reading Strategy Detection Algorithm for Postsecondary Students

American Journal of Speech-Language Pathology ◽

10.1044/2019_ajslp-18-0181 ◽

2019 ◽

Vol 28 (3) ◽

pp. 1257-1267 ◽

Cited By ~ 2

Author(s):

Priya Kucheria ◽

McKay Moore Sohlberg ◽

Jason Prideaux ◽

Stephen Fickas

Keyword(s):

Academic Success ◽

Undergraduate Students ◽

Expository Text ◽

Reading Strategy ◽

Detection Algorithm ◽

Expository Texts ◽

Human Observer ◽

Behavioral Strategies ◽

Periodic Review ◽

Wide Range

PurposeAn important predictor of postsecondary academic success is an individual's reading comprehension skills. Postsecondary readers apply a wide range of behavioral strategies to process text for learning purposes. Currently, no tools exist to detect a reader's use of strategies. The primary aim of this study was to develop Read, Understand, Learn, & Excel, an automated tool designed to detect reading strategy use and explore its accuracy in detecting strategies when students read digital, expository text.MethodAn iterative design was used to develop the computer algorithm for detecting 9 reading strategies. Twelve undergraduate students read 2 expository texts that were equated for length and complexity. A human observer documented the strategies employed by each reader, whereas the computer used digital sequences to detect the same strategies. Data were then coded and analyzed to determine agreement between the 2 sources of strategy detection (i.e., the computer and the observer).ResultsAgreement between the computer- and human-coded strategies was 75% or higher for 6 out of the 9 strategies. Only 3 out of the 9 strategies–previewing content, evaluating amount of remaining text, and periodic review and/or iterative summarizing–had less than 60% agreement.ConclusionRead, Understand, Learn, & Excel provides proof of concept that a reader's approach to engaging with academic text can be objectively and automatically captured. Clinical implications and suggestions to improve the sensitivity of the code are discussed.Supplemental Materialhttps://doi.org/10.23641/asha.8204786

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Response in Growth, Scute Development, and Whole-Body Ion Composition of Acipenser fulvescens Reared in Water of Differing Chemistries

Animals ◽

10.3390/ani11051419 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1419

Author(s):

Janet Genz ◽

Rachael Hicks

Keyword(s):

River Water ◽

Growth And Development ◽

Lake Sturgeon ◽

Whole Body ◽

Acipenser Fulvescens ◽

Water Type ◽

Ion Composition ◽

Ion Concentrations ◽

Before And After ◽

Yolk Absorption

In fishes, environmental ion availability can have substantial effects on growth and development. This study examined the development of Lake Sturgeon in response to the varying environmental ion availability that they experience as part of a conservation stocking program. We reared sturgeon in natural water from the Coosa River, which had higher concentrations of Mg2+, Na+, and Zn2+ than standard hatchery conditions, while [Ca2+] at the Warm Springs National Fish Hatchery was 2× higher than in the Coosa River. Eggs were hatched in each water type and the larvae were sampled at time points before and after yolk absorption during the first 8 weeks of development. Total length and weight in WSNFH larvae were significantly higher than larvae in Coosa River water starting at 8 dph, indicating that growth was dependent on the different environmental ion levels. Concentrations of the ions of interest were also determined for whole-body acid digests of the exposed Lake Sturgeon. We found that Lake Sturgeon reared in Coosa River water had significantly higher magnesium and zinc than Lake Sturgeon reared in WSNFH water (p < 0.05), while calcium was significantly higher in WSNFH than Coosa River water. This difference shows that different environmental ion concentrations also impact the overall development of larval Lake Sturgeon.

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Molecular survey of vector-borne diseases in two groups of domestic dogs from Lisbon, Portugal

Parasites & Vectors ◽

10.1186/s13071-021-04650-4 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Ana Mafalda Dordio ◽

Relja Beck ◽

Telmo Nunes ◽

Isabel Pereira da Fonseca ◽

Jacinto Gomes

Keyword(s):

Clinical Status ◽

Molecular Methods ◽

Hepatozoon Canis ◽

Clinical Approach ◽

Limited Information ◽

Vector Borne Diseases ◽

Wide Range ◽

Other Information ◽

Southern Portugal ◽

Vector Borne

Abstract Background Canine vector-borne diseases (CVBDs) are caused by a wide range of pathogens transmitted by arthropods. They have been an issue of growing importance in recent years; however, there is limited information about the vector-borne pathogens circulating in Portugal. The aim of the present study was to detect canine vector-borne bacteria and protozoa of veterinary and zoonotic importance using molecular methods. Methods One hundred and forty-two dogs from Lisbon, southern Portugal, were tested: 48 dogs from a veterinary hospital clinically suspected of vector-borne diseases and 94 apparently healthy dogs from shelters. Anaplasma spp./Ehrlichia spp., Babesia/Theileria spp., Hepatozoon spp., and Mycoplasma spp. infections were detected by PCR from blood samples and examined under light microscopy. Other information including clinical status and diagnostic test results were collected for each animal. Results Infections were detected by PCR in 48 (33.80%) dogs. Single infections were found in 35 dogs (24.64%), and co-infections were found in 13 (9.15%) dogs. Twenty-nine (20.42%) dogs were positive for Hepatozoon spp., 15 (10.56%) for Mycoplasma spp., 11 (7.75%) for Anaplasma spp./Ehrlichia spp., and six (4.21%) for Babesia spp. DNA sequencing was used to identify Babesia vogeli (2.81%), Babesia canis (1.40%), Hepatozoon canis (20.42%), Mycoplasma haematoparvum (2.11%), Mycoplasma haemocanis (8.45%), Anaplasma platys (7.04%), and Ehrlichia canis (0.70%). Conclusions This is the first molecular identification of B. canis and M. haematoparvum in dogs from southern Portugal. This study highlights the importance of molecular methods to identify CVBD pathogens in endemic areas and helps to guide the clinical approach of veterinarians in practice.

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SET-VALUED PERFORMANCE APPROXIMATIONS FOR THE QUEUE GIVEN PARTIAL INFORMATION

Probability in the Engineering and Informational Sciences ◽

10.1017/s0269964820000509 ◽

2020 ◽

pp. 1-23

Author(s):

Yan Chen ◽

Ward Whitt

Keyword(s):

Steady State ◽

Decay Rate ◽

Waiting Time ◽

Partial Information ◽

Upper And Lower Bounds ◽

Interarrival Time ◽

Limited Information ◽

Wide Range ◽

The Mean ◽

Third Moment

In order to understand queueing performance given only partial information about the model, we propose determining intervals of likely values of performance measures given that limited information. We illustrate this approach for the mean steady-state waiting time in the $GI/GI/K$ queue. We start by specifying the first two moments of the interarrival-time and service-time distributions, and then consider additional information about these underlying distributions, in particular, a third moment and a Laplace transform value. As a theoretical basis, we apply extremal models yielding tight upper and lower bounds on the asymptotic decay rate of the steady-state waiting-time tail probability. We illustrate by constructing the theoretically justified intervals of values for the decay rate and the associated heuristically determined interval of values for the mean waiting times. Without extra information, the extremal models involve two-point distributions, which yield a wide range for the mean. Adding constraints on the third moment and a transform value produces three-point extremal distributions, which significantly reduce the range, producing practical levels of accuracy.

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Tropical cyclones cumulatively control regional carbon fluxes in Everglades mangrove wetlands (Florida, USA)

Scientific Reports ◽

10.1038/s41598-021-92899-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Xiaochen Zhao ◽

Victor H. Rivera-Monroy ◽

Luis M. Farfán ◽

Henry Briceño ◽

Edward Castañeda-Moya ◽

...

Keyword(s):

Tropical Cyclones ◽

Functional Role ◽

Net Primary Productivity ◽

Dissolved Inorganic Carbon ◽

Regional Climate ◽

Regional Climate Change ◽

Neotropical Region ◽

Limited Information ◽

Organic C ◽

Wide Range

AbstractMangroves are the most blue-carbon rich coastal wetlands contributing to the reduction of atmospheric CO2 through photosynthesis (sequestration) and high soil organic carbon (C) storage. Globally, mangroves are increasingly impacted by human and natural disturbances under climate warming, including pervasive pulsing tropical cyclones. However, there is limited information assessing cyclone’s functional role in regulating wetlands carbon cycling from annual to decadal scales. Here we show how cyclones with a wide range of integrated kinetic energy (IKE) impact C fluxes in the Everglades, a neotropical region with high cyclone landing frequency. Using long-term mangrove Net Primary Productivity (Litterfall, NPPL) data (2001–2018), we estimated cyclone-induced litterfall particulate organic C (litter-POC) export from mangroves to estuarine waters. Our analysis revealed that this lateral litter-POC flux (71–205 g C m−2 year−1)—currently unaccounted in global C budgets—is similar to C burial rates (69–157 g C m−2 year−1) and dissolved inorganic carbon (DIC, 61–229 g C m−2 year−1) export. We proposed a statistical model (PULITER) between IKE-based pulse index and NPPL to determine cyclone’s impact on mangrove role as C sink or source. Including the cyclone’s functional role in regulating mangrove C fluxes is critical to developing local and regional climate change mitigation plans.

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Natural anti-phosphorylcholine (PC) antibodies in lake sturgeon, Acipenser fulvescens Rafinesque, 1817 (Chondrostei: Acipenseridae)

Fish & Shellfish Immunology ◽

10.1006/fsim.1994.1034 ◽

1994 ◽

Vol 4 (5) ◽

pp. 399-401 ◽

Cited By ~ 3

Author(s):

Anndo Choudhury ◽

Terry A. Dick

Keyword(s):

Lake Sturgeon ◽

Acipenser Fulvescens

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Seasonal Variation in Plasma Nonesterified Fatty Acids of Lake Sturgeon (Acipenser fulvescens) in the Vicinity of Hydroelectric Facilities

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f93-268 ◽

1993 ◽

Vol 50 (11) ◽

pp. 2440-2447 ◽

Cited By ~ 15

Author(s):

R. S. McKinley ◽

T. D. Singer ◽

J. S. Ballantyne ◽

G. Power

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Lake Sturgeon ◽

Acipenser Fulvescens ◽

Total Plasma ◽

Nefa Concentration ◽

Plasma Nefa ◽

Nonesterified Fatty Acids ◽

Plasma Nefa Concentration ◽

Fatty Acid Species

To establish the effects of hydroelectric generation on the health of lake sturgeon (Acipenser fulvescens), seasonal variations in plasma nonesterified fatty acids (NEFAs) upstream and downstream from hydroelectric stations were measured over a 2-yr period. Plasma NEFA profiles were also compared up- and downstream of the stations for differences in utilization of individual NEFA species as substrates for lipid oxidation. Significantly higher levels of total plasma NEFA were found in lake sturgeon upstream (2355 ± 395.9 nmol/mL) compared with those downstream (798 ± 133.5 nmol/mL) of the generating stations during the spring. The NEFA profiles for several key fatty acid species differed significantly among seasons up- and downstream of the facilities. In particular, during spring and summer, the levels of oleic acid (18:1n9) were highest upstream of the stations and levels of a polyunsaturated fatty acid, docosahexaenoic acid (22:6n3), were higher below rather than above the stations. The differences in plasma NEFA concentration may be attributed to altered nutritional status due to the varying flow regime located downstream of the hydroelectric stations.

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