Predictive potential of genotypes within the prolactin, growth hormone and insulin -like growth factor-I pathways in genetic evaluation of 305 days milk yield in Holstein cows in Sonora, Mexico

Includes bibliographical references.2015 Summer.The objective of this study was to calculate a molecular breeding value (MBV) using single nucleotide polymorphims (SNP) within genes of the prolactin (PRL) and growth hormone and insulin-like growth factor (GH-IGF1) pathways associated with milk production traits and evaluate their effectiveness in genetic prediction in Holstein cows in Sonora, Mexico. We hypothesized that MBV constructed using DNA markers within the PRL and GH-IGF1 pathways have the potential to predict milk production traits in heat-stressed lactating Holstein cows. The data contained observations of 659 Holstein dairy cows collected during 2012 from the city of Obregón, Sonora, Mexico. Milk yield observations were recorded monthly and 305 d milk yield was calculated. Cows were genotyped for 179 tag SNP within 43 genes in the PRL and GH-IGF1 pathways. Eight SNP within 5 genes were associated with 305d milk yield (P ≤ 0.05). No previous research reported these associations. Their effects were used to estimate a MBV. The linear correlation of the MBV and 305 d milk yield was 0.21 and the adjusted R² was 4.5%. Genetic parameters were estimated in ASREML for 305 d milk yield (h² = 0.39 ± 0.11). A training and predicting exercise, was performed using SAS 9.4 with the same data set. The SNP effects and association were estimated and used to calculate an MBV. The MBV was estimated and evaluated by comparing estimates from a 5-fold strategy of random clustering. This procedure was repeated five times, resulting in five MBV. To evaluate the effectiveness of these MBV, correlations and adjusted R² were estimated between MBV and 305 d milk yield. One MBV (MBV5) was correlated (-0.27) and had an adjusted R² of 6.37%. The MBV estimated from SNP within the PRL and GH-IGF1 pathways genes was positive but weakly associated with 305 d milk yield. In the training-predicting exercise, only 1 of the 5 MBV explained a portion of the variation in 305 d milk yield. The small amount of phenotypic variation may be due to the small numbers of SNP used to calculate the MBV and the polygenic nature of the trait under heat stress conditions. The quality of the data, could also affect the results. We accept our hypothesis, the MBV was capable of predicting a portion of the phenotypic variation in 305 d milk yield in lactating Holstein cows in Sonora, MX. Nevertheless, the accuracy and amount of variability explained was not enough to be feasible for use in genetic selection procedures

Cross-coupled doa trackers

A new robust, low complexity algorithm for multiuser tracking is proposed, modifying the two-stage parallel architecture of the estimate-maximize (EM) algorithm. The algorithm copes with spatially colored noise, large differences in source powers, multipath, and crossing trajectories. Following a discussion on stability, the simulations demonstrate an asymptotic and tracking behavior that neither the EM nor a nonparallelized tracker can emulate.Peer ReviewedPostprint (published version

Rheological behaviour of fruit and milk-based smoothies

Two of the most important food attributes for today´s fast-moving lifestyle are convenience and healthiness [1-2]. Fast-moving lifestyle specifically affects to elderly people, who are prone to bad-nutrition due to their dental status reducing the consumption of fruits and vegetables [3]. Smoothies are blended beverages, and good examples of convenient and healthy foods for helping to reduce this problem. So, they are gaining increasing market leverage in the beverage sector. Texture and rheological behaviour of foods can determine their acceptability. Therefore, added to nutritious features, smoothies must also account with outstanding mechanical properties. Stability of the products is also a main quality, which can be gained adding a small amount of stabiliser to beverage formulations. But, to avoid opposite effects, stabilisers addition should ameliorate the product texture.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Phase only transmit beamforming for spectrum sharing microwave systems

This paper deals with the problem of phase-only transmit beamforming in spectrum sharing microwave systems. In contrast to sub-6 GHz schemes, general microwave systems require a large number of antennas due to its huge path loss. As a consequence, digital beamforming needs a large number of computational resources compared to analog beamforming, which only needs a single radio-frequency chain, results the less computational demanding solution. Analog schemes are usually composed by a phase shifter network whose elements transmit at a certain fixed power so that the system designer shall compute the phase values for each element given a set of directions. This approach leads to non-convex quadratic problems where the traditional semidefinite relaxation fails to deliver satisfactory outcomes. In order to solve this, we propose a nonsmooth method that behaves well in several scenarios. Numerical evaluations in different spectrum sharing scenarios, which show the performance of our method, are provided.Peer ReviewedPostprint (author's final draft

Multiuser array beamforming based on a neural network mapping

This paper addresses the problem of simultaneous multiuser service. To find a feasible solution to the collision problem, two time reference multibeamformer systems are developed (BPSK TRMB and frequency framing TRMB). Based on a two-stage architecture, they enlarge the potential of existing separating neural networks and the algorithm (EM). Their goal is to perform a low computational simultaneous digital demodulation of users. The results support the frequency framing TRMB as the more robust system, which is able to give service to users in very degradated SNR scenarios; only the decoupling weights and their corresponding High Order Statistics learning is the overhead from a pure superposition of single channel receivers.Peer ReviewedPostprint (published version

High Performance DOA trackers derived from parallel low resolution detectors

Traditionally, high resolution spectral direction of arrival (DOA) estimation has been associated with algorithms rather than with a processing scheme or architecture. Motivated by previous work on feasible implementations of the expectation-maximization algorithm, the authors show that classical bank filter approach can get similar, even better, performance than the most sophisticated algorithms, in terms of performance versus complexity. In fact, the practicality and robustness required for DOA trackers, both in radar and in the mobile communication scenarios to alleviate data fusion and hand-over respectively, makes evident the use of filter-bank or scanning beams for DOA tracking at the expense of resolution. The herein reported tracker enhances complexity and robustness of these schemes, achieving high resolution from the EM architecture. The result is a low complexity tracker with robustness against coherent sources and a resolution close to singular value decomposition (SVD) based methods.Peer ReviewedPostprint (published version

Receptor avanzado de comunicaciones para acceso multiusuario asíncrono

The use of digital antenna arrays to increase the efficiency of a communication link is studied. Specifically, a Time Reference Multi-beamformer/conformer system, is proposed. The goal is the simultaneous demodulation of BPSK-users, regardless their co-channel nature (in frequency and time). For this purpose, the proposed system resorts to the statistical independence of the impinging user signals and to the spatial diversity introduced by the array. A robust High Order Statistics Combiner will be developed. Its potential stands out in the presented simulations, which illustrate the good performance of the designed multiuser system both in the acquisition and tracking.Peer ReviewedPostprint (published version

Estimación recursiva simultánea de potencia y DOA por ajuste de la matriz de covarianza asociada a la apertura

The small error approximation is used to derive a linear relationship between the source parameters (i.e. power levels and directions of arrival or DOA's) and a measurement of the covariance error matrix, defined as the difference between a nonparametric consisten estimate of the spectral density matrix and a covariance model from the scenario parameters (power level and directions of arrival). The resulting framework allows the disign of a recursive algorithm which provides a simultaneous and adaptive estimation of the sources parameters no matter what is the source waveform or modulation. Due to its similarities with the Kalman filter structure [1], good performance is expected, mainly in the presence of sensors' misfunctioning, low signal-to-noise ratio (SNR), etc.Peer ReviewedPostprint (published version

Simultaneous multiuser demodulation based on digital array processing

The use of antenna arrays to increase the efficiency of a communication link is studied. This work addresses a technique to solve the collision problem that takes place when various users ask simultaneously for access. It consists in a Time Reference Multi-beamformer/conformer system (TRM), which is implemented on a two-stage architecture. Taking advantage of the statistical independence of the impinging references and of the spatial diversity introduced by the array, the goal is the simultaneous demodulation of users, regardless their co-channel nature. The results show the increased system capacity for the specific case of a BPSK communication link. Other desirable features as robustness to calibration errors or good performance of the multiuser system both in adquisition and tracking are illustrated.Peer ReviewedPostprint (published version

A new non-linear system for estimating and suppressing narrowband interference in PN spread spectrum modulation

This work develops a novel dynamic fuzzy logic system that, based on a fuzzy basis function expansion, successfully solves the non-linear problem of narrowband interference prediction and rejection in DS-SS. A fuzzy basis function representation provides a natural framework for combining both numerical and linguistic information in a uniform fashion. The result is a low complexity non-linear adaptive line enhancer, which offers a faster convergence rate and an overall better performance over other well-known non-linear line enhancers.Peer ReviewedPostprint (published version