scholarly journals The acoustic multifrequency classification of two sympatric euphausiid species (Meganyctiphanes norvegica and Thysanoessa raschii), with empirical and SDWBA model validation

2013 ◽  
Vol 70 (3) ◽  
pp. 636-649 ◽  
Author(s):  
Ian H. McQuinn ◽  
Maxime Dion ◽  
Jean-François St. Pierre
Keyword(s):  
Model Validation ◽  
Fishery Management ◽  
Noise Removal ◽  
Trophic Levels ◽  
Angle Distribution ◽  
Acoustic Frequency ◽  
Frequency Responses ◽  
Meganyctiphanes Norvegica ◽  
Species Specific

Abstract McQuinn, I. H., Dion, M., and St. Pierre, J.-F. 2013. The acoustic multifrequency classification of two sympatric euphausiid species (Meganyctiphanes norvegica and Thysanoessa raschii), with empirical and SDWBA model validation. – ICES Journal of Marine Science, 70: 636–649. The ecosystem approach to fishery management requires monitoring capabilities at all trophic levels, including pelagic organisms. However, the usefulness of active acoustics for ecosystem monitoring has been limited by ambiguities in the identification of scattering layers. Increasingly, multifrequency acoustic methods are being developed for the classification of scattering layers into species or species groups. We describe a method for distinguishing between sympatric northern and Arctic krill (Meganyctiphanes norvegica and Thysanoessa raschii) using sv amplitude ratios from 38, 120, and 200 kHz data which were pre-processed through a self-noise removal algorithm. Acoustic frequency responses of both euphausiid species were predicted from species-specific parameterizations of a SDWBA physical model using specific body forms (shape, volume, and length) for Arctic and northern krill. Classification and model validation were achieved using macrozooplankton samples collected from multiple-sampler (BIONESS) and ringnet (JackNet) hauls, both equipped with a strobe light to reduce avoidance by euphausiids. SDWBA frequency responses were calculated for a range of orientations (± 45°) and compared with observed frequency responses, solving for orientation by least squares. A tilt angle distribution of N[9°,4°] and N[12°,6°] for T. raschii and M. norvegica, respectively resulted in best fits. The models also provided species-specific TS–length relationships.

scholarly journals Variability in nitrogen-derived trophic levels of Arctic marine biota

Polar Biology ◽  
2020 ◽  
Author(s):  
Renske P. J. Hoondert ◽  
Nico W. van den Brink ◽  
Martine J. van den Heuvel-Greve ◽  
Ad M. J. Ragas ◽  
A. Jan Hendriks
Keyword(s):  
Stable Isotopes ◽  
Enrichment Factors ◽  
Trophic Levels ◽  
The Arctic ◽  
Marine Biota ◽  
Arctic Ecosystems ◽  
Arctic Species ◽  
Single Region ◽  
Benthic Food ◽  
Species Specific

AbstractStable isotopes are often used to provide an indication of the trophic level (TL) of species. TLs may be derived by using food-web-specific enrichment factors in combination with a representative baseline species. It is challenging to sample stable isotopes for all species, regions and seasons in Arctic ecosystems, e.g. because of practical constraints. Species-specific TLs derived from a single region may be used as a proxy for TLs for the Arctic as a whole. However, its suitability is hampered by incomplete knowledge on the variation in TLs. We quantified variation in TLs of Arctic species by collating data on stable isotopes across the Arctic, including corresponding fractionation factors and baseline species. These were used to generate TL distributions for species in both pelagic and benthic food webs for four Arctic areas, which were then used to determine intra-sample, intra-study, intra-region and inter-region variation in TLs. Considerable variation in TLs of species between areas was observed. This is likely due to differences in parameter choice in estimating TLs (e.g. choice of baseline species) and seasonal, temporal and spatial influences. TLs between regions were higher than the variance observed within regions, studies or samples. This implies that TLs derived within one region may not be suitable as a proxy for the Arctic as a whole. The TL distributions derived in this study may be useful in bioaccumulation and climate change studies, as these provide insight in the variability of trophic levels of Arctic species.

scholarly journals Deep Learning Based Depthwise Separable Model For Effective Diagnosis And Classification of Lung Ct Images

2019 ◽  
Vol 9 (1) ◽  
pp. 1808-1819 ◽  
Keyword(s):  
Lung Cancer ◽  
Feature Extraction ◽  
Deep Learning ◽  
Noise Removal ◽  
Ct Images ◽  
Classification Model ◽  
Diagnosis And Classification ◽  
Effective Diagnosis ◽  
Lung Ct

Lung cancer is a serious illness which leads to increased mortality rate globally. The identification of lung cancer at the beginning stage is the probable method of improving the survival rate of the patients. Generally, Computed Tomography (CT) scan is applied for finding the location of the tumor and determines the stage of cancer. Existing works has presented an effective diagnosis classification model for CT lung images. This paper designs an effective diagnosis and classification model for CT lung images. The presented model involves different stages namely pre-processing, segmentation, feature extraction and classification. The initial stage includes an adaptive histogram based equalization (AHE) model for image enhancement and bilateral filtering (BF) model for noise removal. The pre-processed images are fed into the second stage of watershed segmentation model for effectively segment the images. Then, a deep learning based Xception model is applied for prominent feature extraction and the classification takes place by the use of logistic regression (LR) classifier. A comprehensive simulation is carried out to ensure the effective classification of the lung CT images using a benchmark dataset. The outcome implied the outstanding performance of the presented model on the applied test images.

Classification of the Oxbow Lakes of the Hármas-Körös River and Determination of Ways for Further Exploiting the Various Water Regions in the Light of the Water Framework Directive

2017 ◽  
Author(s):  
Józsa Vilmos ◽  
Jacek Kozłowski ◽  
Anna Zróbek-Sokolnik ◽  
Krzysztof Kozłowski ◽  
Piotr Dynowski
Keyword(s):  
Fishery Management ◽  
Ecological Status ◽  
Anthropogenic Factors ◽  
Oxbow Lakes ◽  
Negative Effect ◽  
Juvenile Stages ◽  
The Individual ◽  
The City

Hármas-Koros river lies between the mouth of the Tisza and the city Békés. In the nineteenth century, the work of regulatory her bed was made, which resulted in 44 oxbow lakes were created, of which 36 still exist till today. In presented work 14 oxbow lakes was selected and the following objectives were carried out: 1. The classification of oxbow lakes based on selected criteria: the manner and intensity of water exchange, sediment thickness, redox potential, usage, ichtiofouna. 2. The assessment of the state of spawning and its impact on ichtiofauna. 3. Determination the best methods of water management in particular types of oxbow lakes, which could stop their further degradation. The obtained results led to the following conclusions: - Tested oxbow lakes belong to different categories - Anthropogenic factors had a negative effect on the conditions of fish reproduction and survival of their juvenile stages. - The management of fisheries was not a factor differentiating the individual water regions, but had an impact on the ecological status. - For the maintenance and/or improvement of the natural environment of the individual oxbow lakes significant impact may have fishery management, carried out in the following years.

scholarly journals Development of Computer-Aided Semi-Automatic Diagnosis System for Chronic Post-Stroke Aphasia Classification with Temporal and Parietal Lesions: A Pilot Study

2020 ◽  
Vol 10 (8) ◽  
pp. 2984
Author(s):  
Bhagya Nathali Silva ◽  
Murad Khan ◽  
Ruchire Eranga Wijesinghe ◽  
Samantha Thelijjagoda ◽  
Kijun Han
Keyword(s):  
Inspection System ◽  
Language Therapy ◽  
Acoustic Frequency ◽  
Diagnosis System ◽  
Confrontation Naming ◽  
Number Of Patients ◽  
Wernicke's Aphasia ◽  
Classification Boundary ◽  
Normal Coupling

Survivors of either a hemorrhagic or ischemic stroke tend to acquire aphasia and experience spontaneous recovery during the first six months. Nevertheless, a considerable number of patients sustain aphasia and require speech and language therapy to overcome the difficulties. As a preliminary study, this article aims to distinguish aphasia caused from a temporoparietal lesion. Typically, temporal and parietal lesions cause Wernicke’s aphasia and Anomic aphasia. Differential diagnosis between Anomic and Wernicke’s has become controversial and subjective due to the close resemblance of Wernicke’s to Anomic aphasia when recovering. Hence, this article proposes a clinical diagnosis system that incorporates normal coupling between the acoustic frequencies of speech signals and the language ability of temporoparietal aphasias to delineate classification boundary lines. The proposed inspection system is a hybrid scheme consisting of automated components, such as confrontation naming, repetition, and a manual component, such as comprehension. The study was conducted involving 30 participants clinically diagnosed with temporoparietal aphasias after a stroke and 30 participants who had experienced a stroke without aphasia. The plausibility of accurate classification of Wernicke’s and Anomic aphasia was confirmed using the distinctive acoustic frequency profiles of selected controls. Accuracy of the proposed system and algorithm was confirmed by comparing the obtained diagnosis with the conventional manual diagnosis. Though this preliminary work distinguishes between Anomic and Wernicke’s aphasia, we can claim that the developed algorithm-based inspection model could be a worthwhile solution towards objective classification of other aphasia types.

scholarly journals Species-Specific Identification of Human Adenoviruses by a Multiplex PCR Assay

2000 ◽  
Vol 38 (11) ◽  
pp. 4114-4120 ◽  
Author(s):  
WanHong Xu ◽  
Mike C. McDonough ◽  
Dean D. Erdman
Keyword(s):  
Multiplex Pcr ◽  
Human Adenovirus ◽  
Cost Effective ◽  
Pcr Assay ◽  
Multiplex Pcr Assay ◽  
Amplicon Size ◽  
Species Specific ◽  
Fiber Gene ◽  
Amplification Reaction

A multiplex PCR assay was developed by using primers to the fiber gene that could differentiate human adenovirus (Ad) species A through F in a single amplification reaction. The assay correctly identified the species of all 49 recognized Ad prototype strains as well as 180 geographically and temporally diverse Ad field isolates. Ad serotype 6 (Ad6) (species C), Ad16 (species B), Ad31 (species A), and Ad40 and Ad41 (species F) could also be distinguished by amplicon size within each respective species. In comparison, a previously described Ad species-specific multiplex PCR assay that used primers to the Ad hexon gene gave equivocal results with several serotypes of species B, whereas our multiplex assay amplified all species B serotypes equally well. Our multiplex PCR assay will permit rapid, accurate, and cost-effective classification of Ad isolates.

scholarly journals Species-specific effects of passive warming in an Antarctic moss system

2019 ◽  
Vol 6 (11) ◽  
pp. 190744 ◽  
Author(s):  
Hannah M. Prather ◽  
Angélica Casanova-Katny ◽  
Andrew F. Clements ◽  
Matthew W. Chmielewski ◽  
Mehmet A. Balkan ◽  
...  
Keyword(s):  
Plant Species ◽  
Fungal Biomass ◽  
Trophic Levels ◽  
Moss Species ◽  
Abiotic Environment ◽  
Invertebrate Communities ◽  
Passive Warming ◽  
Specific Effects ◽  
Species Specific ◽  
Antarctic Moss

Polar systems are experiencing rapid climate change and the high sensitivity of these Arctic and Antarctic ecosystems make them especially vulnerable to accelerated ecological transformation. In Antarctica, warming results in a mosaic of ice-free terrestrial habitats dominated by a diverse assemblage of cryptogamic plants (i.e. mosses and lichens). Although these plants provide key habitat for a wide array of microorganisms and invertebrates, we have little understanding of the interaction between trophic levels in this terrestrial ecosystem and whether there are functional effects of plant species on higher trophic levels that may alter with warming. Here, we used open top chambers on Fildes Peninsula, King George Island, Antarctica, to examine the effects of passive warming and moss species on the abiotic environment and ultimately on higher trophic levels. For the dominant mosses, Polytrichastrum alpinum and Sanionia georgicouncinata , we found species-specific effects on the abiotic environment, including moss canopy temperature and soil moisture. In addition, we found distinct shifts in sexual expression in P . alpinum plants under warming compared to mosses without warming, and invertebrate communities in this moss species were strongly correlated with plant reproduction. Mosses under warming had substantially larger total invertebrate communities, and some invertebrate taxa were influenced differentially by moss species. However, warmed moss plants showed lower fungal biomass than control moss plants, and fungal biomass differed between moss species. Our results indicate that continued warming may impact the reproductive output of Antarctic moss species, potentially altering terrestrial ecosystems dynamics from the bottom up. Understanding these effects requires clarifying the foundational, mechanistic role that individual plant species play in mediating complex interactions in Antarctica's terrestrial food webs.

scholarly journals A Bead-Based Flow Cytometric Assay for MonitoringYersinia pestisExposure in Wildlife

2018 ◽  
Vol 56 (7) ◽  
Author(s):  
Jeffrey C. Chandler ◽  
Laurie A. Baeten ◽  
Doreen L. Griffin ◽  
Thomas Gidlewski ◽  
Thomas J. DeLiberto ◽  
...  
Keyword(s):  
Analytical Sensitivity ◽  
Flow Cytometric Assay ◽  
Passive Hemagglutination ◽  
Content Type ◽  
Spatially Correlated ◽  
Flow Cytometric ◽  
Standard Tool ◽  
Specific Igg ◽  
Species Specific

ABSTRACTYersinia pestisis the causative agent of plague and is considered a category A priority pathogen due to its potential for high transmissibility and the significant morbidity and mortality it causes in humans.Y. pestisis endemic to the western United States and much of the world, necessitating programs to monitor for this pathogen on the landscape. Elevated human risk of plague infection has been spatially correlated with spikes in seropositive wildlife numbers, particularly rodent-eating carnivores, which are frequently in contact with the enzootic hosts and the associated arthropod vectors ofY. pestis. In this study, we describe a semiautomated bead-based flow cytometric assay developed for plague monitoring in wildlife called the F1 Luminex plague assay (F1-LPA). Based upon Luminex/Bio-Plex technology, the F1-LPA targets serological responses to the F1 capsular antigen ofY. pestisand was optimized to analyze antibodies eluted from wildlife blood samples preserved on Nobuto filter paper strips. In comparative evaluations with passive hemagglutination, the gold standard tool for wildlife plague serodiagnosis, the F1-LPA demonstrated as much as 64× improvement in analytical sensitivity for F1-specific IgG detection and allowed for unambiguous classification of IgG status. The functionality of the F1-LPA was demonstrated for coyotes and other canids, which are the primary sentinels in wildlife plague monitoring, as well as felids and raccoons. Additionally, assay formats that do not require species-specific immunological reagents, which are not routinely available for several wildlife species used in plague monitoring, were determined to be functional in the F1-LPA.

Speech Recognition Using Combined Fuzzy and Ant Colony algorithm

2016 ◽  
Vol 6 (5) ◽  
pp. 2205
Author(s):  
Fooad Jalili ◽  
Milad Jafari Barani
Keyword(s):  
Speech Recognition ◽  
Dimensionality Reduction ◽  
Input Signal ◽  
Speech Signal ◽  
Fuzzy System ◽  
Ant Colony Algorithm ◽  
Noise Removal ◽  
Ant Colony ◽  
Speech Detection

<p><span>In recent years various methods has been proposed for speech recognition and removing noise from the speech signal became an important issue. In this paper a fuzzy system has been proposed for speech recognition that can obtain accurate results using classification of speech signals with “Ant Colony” algorithm.  First, speech samples are given to the fuzzy system to obtain a pattern for every set of signals that can be helpful for dimensionality reduction, easier checking of outcome and better recognition of signals.  Then, the “ACO” algorithm is used to cluster these signals and determine a cluster for each input signal. Also, with this method we will be able to recognize noise and consider it in a separate cluster and remove it from the input signal. Results show that the accuracy for speech detection and noise removal is desirable.</span></p>

scholarly journals The biggest losers: habitat isolation deconstructs complex food webs from top to bottom

2019 ◽  
Vol 286 (1908) ◽  
pp. 20191177 ◽  
Author(s):  
Remo Ryser ◽  
Johanna Häussler ◽  
Markus Stark ◽  
Ulrich Brose ◽  
Björn C. Rall ◽  
...  
Keyword(s):  
Species Diversity ◽  
Habitat Fragmentation ◽  
Food Web ◽  
Food Webs ◽  
Spatial Dynamics ◽  
Trophic Levels ◽  
Habitat Isolation ◽  
Fragmented Landscapes ◽  
Energy Limitation ◽  
Species Specific

Habitat fragmentation threatens global biodiversity. To date, there is only limited understanding of how the different aspects of habitat fragmentation (habitat loss, number of fragments and isolation) affect species diversity within complex ecological networks such as food webs. Here, we present a dynamic and spatially explicit food web model which integrates complex food web dynamics at the local scale and species-specific dispersal dynamics at the landscape scale, allowing us to study the interplay of local and spatial processes in metacommunities. We here explore how the number of habitat patches, i.e. the number of fragments, and an increase of habitat isolation affect the species diversity patterns of complex food webs ( α -, β -, γ -diversities). We specifically test whether there is a trophic dependency in the effect of these two factors on species diversity. In our model, habitat isolation is the main driver causing species loss and diversity decline. Our results emphasize that large-bodied consumer species at high trophic positions go extinct faster than smaller species at lower trophic levels, despite being superior dispersers that connect fragmented landscapes better. We attribute the loss of top species to a combined effect of higher biomass loss during dispersal with increasing habitat isolation in general, and the associated energy limitation in highly fragmented landscapes, preventing higher trophic levels to persist. To maintain trophic-complex and species-rich communities calls for effective conservation planning which considers the interdependence of trophic and spatial dynamics as well as the spatial context of a landscape and its energy availability.

Sign in / Sign up

Export Citation Format

Share Document