Critical Properties of the Assembly Call of the Common American Crow

Behaviour ◽  
1978 ◽  
Vol 64 (3-4) ◽  
pp. 184-203 ◽  
Author(s):  
Nicholas S. Thompson ◽  
David B. Richards
Keyword(s):  
Sound Source ◽  
Traditional View ◽  
High Rate ◽  
American Crow ◽  
Corvus Brachyrhynchos ◽  
Temporal Properties ◽  
Series Of Experiments ◽  
The Common ◽  
Functional Context ◽  
Better Than

AbstractAccording to tradition, the communication system of the American crow, Corvus brachyrhynchos, consists of an assortment of distinct sounds each of which is used in a particular context and has a unique meaning. Despite this traditional view, we have made field observations which suggested that the sounds employed in various different functional contexts overlap considerably. These observations further suggested that each sound does not have a single unique meaning, but that its meaning varies depending upon how it and similar sounds are temporally organized into calling sequences. In order to investigate this idea, a series of experiments were performed in which the temporal properties of natural sounds recorded from crows in the field were changed. These experiments were concerned primarily with the vocalization known as the assembly call. The assembly call consists of series of sounds which are low, harsh, and variable in pitch and timing. Broadcast to crows in the field, recorded assembly calls provoke an aggregation of crows to the sound source about twenty-five percent of the time. The recordings broadcasted were of two sorts: sequences made up by modifying the temporal properties of a natural assembly call and sequences of sounds derived from calls given in other functional contexts which were then rearranged to approximate the temporal properties of an assembly call. These calls were tested on wild crows in the field. A presentation of a call was counted successful if at least one crow approached the sound source on a direct line. Different calls were compared with respect to the proportion of successful presentations. The results show that not all types of crow sounds can be manufactured into effective assembly calls. A high pitched call, even when arranged to approximate the temporal properties of the assembly call does not assemble crows at rates approaching the rate of assembly to natural assembly calls. On the other hand, the results also show that a sound need not be derived from an assembly call in order to be arranged into an effective assembly call. A call recorded in another functional context, but which has a harsh, grainy quality will assemble crows as well as or better than an assembly call if it is presented in the proper temporal arrangement. In fact, the highest rates of success were provoked by a sequence of such sounds having a high rate of emission and organized into short cycles of increasing rate. Such a call is two to four times more effective than a natural assembly call. These results are inconsistent with the traditional view that each particular caw in the repertoire of a crow has a discrete stable meaning. An alternate hypothesis is suggested in which the meaning of a sequence of crow sounds is thought to depend not only on the properties of the caws but upon the temporal properties of the sequence as well.

scholarly journals Correlational Neural Networks

2016 ◽  
Vol 28 (2) ◽  
pp. 257-285 ◽  
Author(s):  
Sarath Chandar ◽  
Mitesh M. Khapra ◽  
Hugo Larochelle ◽  
Balaraman Ravindran
Keyword(s):  
Canonical Correlation ◽  
State Of The Art ◽  
Representation Learning ◽  
Advantages And Disadvantages ◽  
Common Representation ◽  
Series Of Experiments ◽  
The Common ◽  
Cross Language ◽  
Joint Representation ◽  
Better Than

Common representation learning (CRL), wherein different descriptions (or views) of the data are embedded in a common subspace, has been receiving a lot of attention recently. Two popular paradigms here are canonical correlation analysis (CCA)–based approaches and autoencoder (AE)–based approaches. CCA-based approaches learn a joint representation by maximizing correlation of the views when projected to the common subspace. AE-based methods learn a common representation by minimizing the error of reconstructing the two views. Each of these approaches has its own advantages and disadvantages. For example, while CCA-based approaches outperform AE-based approaches for the task of transfer learning, they are not as scalable as the latter. In this work, we propose an AE-based approach, correlational neural network (CorrNet), that explicitly maximizes correlation among the views when projected to the common subspace. Through a series of experiments, we demonstrate that the proposed CorrNet is better than AE and CCA with respect to its ability to learn correlated common representations. We employ CorrNet for several cross-language tasks and show that the representations learned using it perform better than the ones learned using other state-of-the-art approaches.

Scanning Secondary Electron Microscopy of Myofibrils Using Transmission Techniques

1975 ◽  
Vol 33 ◽  
pp. 556-557
Author(s):  
M. K. Lamvik
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Carbon Films ◽  
Photographic Recording ◽  
Transmission Electron ◽  
Thin Carbon ◽  
The Common ◽  
Scanning Electron ◽  
Better Than ◽  
Cellular Organelles

When observing small objects such as cellular organelles by scanning electron microscopy, it is often valuable to use the techniques of transmission electron microscopy. The common practice of mounting and coating for SEM may not always be necessary. These possibilities are illustrated using vertebrate skeletal muscle myofibrils.Micrographs for this study were made using a Hitachi HFS-2 scanning electron microscope, with photographic recording usually done at 60 seconds per frame. The instrument was operated at 25 kV, with a specimen chamber vacuum usually better than 10-7 torr. Myofibrils were obtained from rabbit back muscle using the method of Zak et al. To show the component filaments of this contractile organelle, the myofibrils were partially disrupted by agitation in a relaxing medium. A brief centrifugation was done to clear the solution of most of the undisrupted myofibrils before a drop was placed on the grid. Standard 3 mm transmission electron microscope grids covered with thin carbon films were used in this study.

STUDY ON THRIVE SCORE IN THE PROGNOSIS OF ISCHEMIC STROKE

2017 ◽  
pp. 22-24
Author(s):  
Thi Thao Nhi Tran ◽  
Dinh Toan Nguyen
Keyword(s):  
Ischemic Stroke ◽  
Clinical Outcome ◽  
Regression Models ◽  
Cross Sectional Study ◽  
High Rate ◽  
Vascular Events ◽  
Cross Sectional ◽  
Key Words Ischemic Stroke ◽  
Outcome Mortality ◽  
Better Than

Background and Purpose: Stroke is the second cause of mortality and the leading cause of disability. Using the clinical scale to predict the outcome of the patient play an important role in clinical practice. The Totaled Health Risks in Vascular Events (THRIVE) score has shown broad utility, allowing prediction of clinical outcome and death. Methods: A cross-sectional study conducting on 102 patients with acute ischemic stroke using THRIVE score. The outcome of patient was assessed by mRankin in the day of 30 after stroke. Statistic analysis using SPSS 15.0. Results: There was 60.4% patient in the group with THRIVE score 0 – 2 points having a good outcome (mRS 0 - 2), patient group with THRIVE score 6 - 9 having a high rate of bad outcome and mortality. Having a positive correlation between THRIVE score on admission and mRankin score at the day 30 after stroke with r = 0.712. THRIVE score strongly predicts clinical outcome with ROC-AUC was 0.814 (95% CI 0.735 - 0.893, p<0.001), Se 69%, Sp 84% and the cut-off was 2. THRIVE score strongly predicts mortality with ROC-AUC was 0.856 (95% CI 0.756 - 0.956, p<0.01), Se 86%, Sp 77% and the cut-off was 3. Analysis of prognostic factors by multivariate regression models showed that THRIVE score was only independent prognostic factor for the outcome of post stroke patients. Conclusions: The THRIVE score is a simple-to-use tool to predict clinical outcome, mortality in patients with ischemic stroke. Despite its simplicity, the THRIVE score performs better than several other outcome prediction tools. Key words: Ischemic stroke, THRIVE, prognosis, outcome, mortality

Research of the activity and viability of spermatozoa at different concentrations and proportions of diluents after incubation

2020 ◽  
pp. 88-95
Author(s):  
Svitlana Lobchenko ◽  
Tetiana Husar ◽  
Viktor Lobchenko
Keyword(s):  
Plasma Concentration ◽  
Incubation Time ◽  
Coefficient Of Variation ◽  
Incubation Medium ◽  
Wide Range ◽  
Series Of Experiments ◽  
The Subject ◽  
Boar Spermatozoa ◽  
Native Plasma ◽  
Better Than

The results of studies of the viability of spermatozoa with different incubation time at different concentrations and using different diluents are highlighted in the article. (Un) concentrated spermatozoa were diluented: 1) with their native plasma; 2) medium 199; 3) a mixture of equal volumes of plasma and medium 199. The experiment was designed to generate experimental samples with spermatozoa concentrations prepared according to the method, namely: 0.2; 0.1; 0.05; 0.025 billion / ml. The sperm was evaluated after 2, 4, 6 and 8 hours. The perspective of such a study is significant and makes it possible to research various aspects of the subject in a wide range. In this regard, a series of experiments were conducted in this area. The data obtained are statistically processed and allow us to highlight the results that relate to each stage of the study. In particular, in this article it was found out some regularities between the viability of sperm, the type of diluent and the rate of rarefaction, as evidenced by the data presented in the tables. As a result of sperm incubation, the viability of spermatozoa remains at least the highest trend when sperm are diluted to a concentration of 0.1 billion / ml, regardless of the type of diluent used. To maintain the viability of sperm using this concentration of medium 199 is not better than its native plasma, and its mixture with an equal volume of plasma through any length of time incubation of such sperm. Most often it is at this concentration of sperm that their viability is characterized by the lowest coefficient of variation, regardless of the type of diluent used, which may indicate the greatest stability of the result under these conditions. The viability of spermatozoa with a concentration of 0.1 billion / ml is statistically significantly reduced only after 6 or even 8 hours of incubation. If the sperm are incubated for only 2 hours, regardless of the type of diluent used, the sperm concentrations tested do not affect the viability of the sperm. Key words: boar, spermatozoa, sperm plasma, concentration, incubation, medium 199, activity, viability, rarefaction.

Research on Quick Superplastic Forming for Aluminium Alloy Sheet

2012 ◽  
Vol 735 ◽  
pp. 301-306 ◽  
Author(s):  
Hai Jian Liang ◽  
Xiao Wei Wu ◽  
Yong Wang ◽  
Quan Lin Jin ◽  
Zhao Li Ma ◽  
...  
Keyword(s):  
Mass Production ◽  
Simulation Experiment ◽  
Hot Stamping ◽  
Superplastic Forming ◽  
Alloy Sheet ◽  
High Rate ◽  
Hot Forming ◽  
Forming Technology ◽  
Complex Process ◽  
Better Than

This article describes the high rate superplastic forming. The high rate superplastic forming technology is a new complex process,which integrates hot stamping and superplastic forming .It has feature of rapidity of the hot stamping and character of excellent formability of the superplastic forming.We obtained the best proportion of the hot forming and the superplastic forming through simulation experiment, and formed a car’s abonnet by applying the proportion.Compared with the high rate superplastic forming,the forming quality is better than that of hot forming. and the forming time is less than that of superplastic forming. Result shows that ,the high rate superplastic forming technology can meet the requirements for mass production.

scholarly journals SPPD: A Novel Reassembly Method for 3D Terracotta Warrior Fragments Based on Fracture Surface Information

2021 ◽  
Vol 10 (8) ◽  
pp. 525
Author(s):  
Wenmin Yao ◽  
Tong Chu ◽  
Wenlong Tang ◽  
Jingyu Wang ◽  
Xin Cao ◽  
...  
Keyword(s):  
Fracture Surface ◽  
Principal Component ◽  
Point Clouds ◽  
Three Dimension ◽  
Registration Method ◽  
Series Of Experiments ◽  
Coarse To Fine ◽  
Fine Registration ◽  
Common Situation ◽  
Better Than

As one of China′s most precious cultural relics, the excavation and protection of the Terracotta Warriors pose significant challenges to archaeologists. A fairly common situation in the excavation is that the Terracotta Warriors are mostly found in the form of fragments, and manual reassembly among numerous fragments is laborious and time-consuming. This work presents a fracture-surface-based reassembling method, which is composed of SiamesePointNet, principal component analysis (PCA), and deep closest point (DCP), and is named SPPD. Firstly, SiamesePointNet is proposed to determine whether a pair of point clouds of 3D Terracotta Warrior fragments can be reassembled. Then, a coarse-to-fine registration method based on PCA and DCP is proposed to register the two fragments into a reassembled one. The above two steps iterate until the termination condition is met. A series of experiments on real-world examples are conducted, and the results demonstrate that the proposed method performs better than the conventional reassembling methods. We hope this work can provide a valuable tool for the virtual restoration of three-dimension cultural heritage artifacts.

Evaluation of Gas-Liquid Chromatography in Assays for Blood Volatiles

1965 ◽  
Vol 11 (11) ◽  
pp. 1023-1035 ◽  
Author(s):  
Alan Mather ◽  
Angel Assimos
Keyword(s):  
Liquid Chromatography ◽  
Alcohol Concentration ◽  
Quantitative Assay ◽  
Gas Liquid Chromatography ◽  
Internal Reference ◽  
Detection And Identification ◽  
Large Populations ◽  
The Common ◽  
Low Levels ◽  
Better Than

Abstract A simple screening by gas-liquid chromatography (GLC) can provide definitive answers in the detection and identification of a number of volatile substances, including acetone and the common alcohols. After identification, quantitative assay by an internal-reference technic yields highly specific values for ethyl alcohol concentration with a precision at least equal to (and for low levels, better than) that of conventional assays. The unique advantage of GLC is in its simultaneous quantitative assay of mixtures, some of which cannot be satisfactorily assayed or even recognized in any other way. The combination of speed and negligible sample volumes render the technic valuable for sequential studies on capillary blood samples and, potentially, for mass screening of large populations.

Second Paper: Deep Drawing and Free Forming Using a Water Hammer Technique

1964 ◽  
Vol 179 (1) ◽  
pp. 222-233 ◽  
Author(s):  
A. P. Vafiadakis ◽  
W. Johnson ◽  
I. S. Donaldson
Keyword(s):  
Deep Drawing ◽  
Time History ◽  
Water Hammer ◽  
High Rate ◽  
Pressure Time ◽  
Order Of Magnitude ◽  
History Of ◽  
Overall Efficiency ◽  
Initial Movement ◽  
Better Than

Earlier work on a water-hammer technique for high-rate forming of sheet metal has been extended to include work on deep drawing using lead plugs. A study of the pressure-time history of a deforming blank during its initial movement is reported. An assessment of the overall efficiency of the process has been made and is found to be about 50 per cent; this is an order of magnitude better than that found with comparable electro-hydraulic and explosive methods.

Synthetic individual binaural audio delivery by pinna image processing

2014 ◽  
Vol 10 (3) ◽  
pp. 239-254 ◽  
Author(s):  
Simone Spagnol ◽  
Michele Geronazzo ◽  
Davide Rocchesso ◽  
Federico Avanzini
Keyword(s):  
Sound Source ◽  
Low Complexity ◽  
Head Orientation ◽  
Sound Sources ◽  
Content Type ◽  
Localization Test ◽  
Subjective Measurements ◽  
Head Related Transfer Function ◽  
Practical Implications ◽  
Better Than

Purpose – The purpose of this paper is to present a system for customized binaural audio delivery based on the extraction of relevant features from a 2-D representation of the listener’s pinna. Design/methodology/approach – The most significant pinna contours are extracted by means of multi-flash imaging, and they provide values for the parameters of a structural head-related transfer function (HRTF) model. The HRTF model spatializes a given sound file according to the listener’s head orientation, tracked by sensor-equipped headphones, with respect to the virtual sound source. Findings – A preliminary localization test shows that the model is able to statically render the elevation of a virtual sound source better than non-individual HRTFs. Research limitations/implications – Results encourage a deeper analysis of the psychoacoustic impact that the individualized HRTF model has on perceived elevation of virtual sound sources. Practical implications – The model has low complexity and is suitable for implementation on mobile devices. The resulting hardware/software package will hopefully allow an easy and low-tech fruition of custom spatial audio to any user. Originality/value – The authors show that custom binaural audio can be successfully deployed without the need of cumbersome subjective measurements.

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