Sea lice threaten the welfare of farmed Atlantic salmon and the sustainability of fish farming across the world. Chemical treatments are the major method of control but drug resistance means that alternatives are urgently needed. Selective breeding can be a cheap and effective alternative. Here, we combine experimental trials and diagnostics to provide a practical protocol for quantifying resistance to sea lice. We then combined quantitative genetics with epidemiological modelling to make the first prediction of the response to selection, quantified in terms of reduced need for chemical treatments. We infected over 1400 young fish with Lepeophtheirus salmonis, the most important species in the Northern Hemisphere. Mechanisms of resistance were expressed early in infection. Consequently, the number of lice per fish and the ranking of families were very similar at 7 and 17 days post infection, providing a stable window for assessing susceptibility to infection. The heritability of lice numbers within this time window was moderately high at 0.3, confirming that selective breeding is viable. We combined an epidemiological model of sea lice infection and control on a salmon farm with genetic variation in susceptibility among individuals. We simulated 10 generations of selective breeding and examined the frequency of treatments needed to control infection. Our model predicted that substantially fewer chemical treatments are needed to control lice outbreaks in selected populations and chemical treatment could be unnecessary after 10 generations of selection. Selective breeding for sea lice resistance should reduce the impact of sea lice on fish health and thus substantially improve the sustainability of Atlantic salmon production. 相似文献
A high-sensitivity human muscle-vibration measurement (MMG) sensor adapted to clinical use is presented. The muscle vibration phenomenon is modeled and investigated to optimize the measurement technique. The sensor uses an acoustic impedance adaptation technique to convert the skin surface vibration in terms of acoustic pressure, which is sensed by a microphone. The device is calibrated and gives the real amplitude of the vibration. It is also well fitted to measure other physiological vibrations in the 2 Hz-1 kHz range 相似文献
Artificial Intelligence Review - Visual object tracking has become one of the most active research topics in computer vision, and it has been applied in several commercial... 相似文献
The phospholipid fatty acid composition of the Calcarean spongeLeucosolenia canariensis was studied, and no Δ5,9 fatty acids were detected. These results are in contrast to the phospholipids from sponges belonging to the class Demospongiae
where Δ5,9 fatty acids are predominant. Odd branched-chain fatty acids between 17 and 19 carbons accounted for 26% of the
total fatty acids ofL. canariensis, while straight-chain fatty acids between 16 and 22 carbons accounted for 61% of the total fatty acid composition. The sterol
composition ofL. canariensis is also reported, and only Δ5,7,22 sterols were observed. 相似文献
This paper proposes an adaptive Wiener filtering method for speech enhancement. This method depends on the adaptation of the filter transfer function from sample to sample based on the speech signal statistics; the local mean and the local variance. It is implemented in the time domain rather than in the frequency domain to accommodate for the time-varying nature of the speech signals. The proposed method is compared to the traditional frequency-domain Wiener filtering, spectral subtraction and wavelet denoising methods using different speech quality metrics. The simulation results reveal the superiority of the proposed Wiener filtering method in the case of Additive White Gaussian Noise (AWGN) as well as colored noise. 相似文献
The singular value decomposition (SVD) mathematical technique is utilized, in this paper, for audio watermarking in time and
transform domains. Firstly, the audio signal in time or an appropriate transform domain is transformed to a 2-D format. The
SVD algorithm is applied on this 2-D matrix, and an image watermark is added to the matrix of singular values (SVs) with a
small weight, to guarantee the possible extraction of the watermark without introducing harmful distortions to the audio signal.
The transformation of the audio signal between the 1-D and 2-D formats is performed in the well-known lexicographic ordering
method used in image processing. A comparison study is presented in the paper between the time and transform domains as possible
hosting media for watermark embedding. Experimental results are in favor of watermark embedding in the time domain if the
distortion level in the audio signal is to be kept as low as possible with a high detection probability. The proposed algorithm
is utilized also for embedding chaotic encrypted watermarks to increase the level of security. Experimental results show that
watermarks embedded with the proposed algorithm can survive several attacks. A segment-by-segment implementation of the proposed
SVD audio watermarking algorithm is also presented to enhance the detectability of the watermark in the presence of severe
attacks. 相似文献
We perceive big data with massive datasets of complex and variegated structures in the modern era. Such attributes formulate hindrances while analyzing and storing the data to generate apt aftermaths. Privacy and security are the colossal perturb in the domain space of extensive data analysis. In this paper, our foremost priority is the computing technologies that focus on big data, IoT (Internet of Things), Cloud Computing, Blockchain, and fog computing. Among these, Cloud Computing follows the role of providing on-demand services to their customers by optimizing the cost factor. AWS, Azure, Google Cloud are the major cloud providers today. Fog computing offers new insights into the extension of cloud computing systems by procuring services to the edges of the network. In collaboration with multiple technologies, the Internet of Things takes this into effect, which solves the labyrinth of dealing with advanced services considering its significance in varied application domains. The Blockchain is a dataset that entertains many applications ranging from the fields of crypto-currency to smart contracts. The prospect of this research paper is to present the critical analysis and review it under the umbrella of existing extensive data systems. In this paper, we attend to critics' reviews and address the existing threats to the security of extensive data systems. Moreover, we scrutinize the security attacks on computing systems based upon Cloud, Blockchain, IoT, and fog. This paper lucidly illustrates the different threat behaviour and their impacts on complementary computational technologies. The authors have mooted a precise analysis of cloud-based technologies and discussed their defense mechanism and the security issues of mobile healthcare.
Semiconductors - In this work, TiO2 thin films were deposited onto glass substrate by two different techniques: sol–gel dip-coating (SG) and reactive DC magnetron sputtering (Sput). The... 相似文献