The Role of Exosomal Epigenetic Modifiers in Cell Communication and Fertility of Dairy Cows

Abnormal uterine function affects conception rate and embryo development, thereby leading to poor fertility and reproduction failure. Exosomes are a nanosized subclass of extracellular vesicles (EV) that have important functions as intercellular communicators. They contain and carry transferable bioactive substances including micro RNA (miRNA) for target cells. Elements of the cargo can provide epigenetic modifications of the recipient cells and may have crucial roles in mechanisms of reproduction. The dairy industry accounts for a substantial portion of the economy of many agricultural countries. Exosomes can enhance the expression of inflammatory mediators in the endometrium, which contribute to various inflammatory diseases in transition dairy cows. This results in reduced fertility which leads to reduced milk production and increased cow maintenance costs. Thus, gaining a clear knowledge of exosomal epigenetic modifiers is critical to improving the breeding success and profitability of dairy farms. This review provides a brief overview of how exosomal miRNA contributes to inflammatory diseases and hence to poor fertility, particularly in dairy cows.     

Proteome profiling of exosomes derived from plasma of heifers with divergent genetic merit for fertility

The current study evaluated exosomes isolated from plasma of heifers bred to have high or low fertility through developing extreme diversity in fertility breeding values, however, key animal traits (e.g., body weight, milk production, and percentage of North American genetics) remained similar between the 2 groups. The exosomes were isolated by a combined ultracentrifugation and size exclusion chromatography approach and characterized by their size distribution (nanoparticle tracking analysis), morphology (transmission electron microscopy), and presence of exosomal markers (immunoblotting). In addition, a targeted mass spectrometry approach was used to confirm the presence of 2 exosomal markers, tumor susceptibility gene 101 and flotillin 1. The number of exosomes from plasma of high fertility heifers was greater compared with low fertility heifers. Interestingly, the exosomal proteomic profile, evaluated using mass spectrometry, identified 89 and 116 proteins in the high and low fertility heifers respectively, of which 4 and 31 were unique, respectively. These include proteins associated with specific biological processes and molecular functions of fertility. Most notably, the tetratricopeptide repeat protein 41-related, glycodelin, and kelch-like protein 8 were identified in plasma exosomes unique to the low fertility heifers. These proteins are suggested to play a role in reproduction; however, the role of these proteins in dairy cow reproduction remains to be elucidated. Their identification underscores the potential for proteins within exosomes to provide information on the fertility status and physiological condition of the cow. This may potentially lead to the development of prognostic tools and interventions to improving dairy cow fertility.     

Review of Recent Advances in Non-invasive, Flexi-ble, Wearable Sweat Monitoring Sensors

Wearable health-monitoring devices are novel and integral developments based on smart-textiles. Conventional wearable technology consists of micro-controllers and a variety of electronic devices embedded on the skin, or in-corporated into the apparels, where they act as signal receptors, analytical devices and transmitters of the signals generated from the human body. Invasive methods are currently more commonly practiced where biofluids are obtained by penetrating the body by incision or injection, while in non-invasive methods no such penetrations take place. A critical review of current non-invasive wearable technology, including colorimetric, enzymatic, pH based, electrochemical and conductivity sensors, is presented in this paper along with the challenges and limitations they pose. Additionally, novel techniques of analysis have been explored concluding that a textile-based medium offers higher compatibility for in-tegration of such sensors in comparison to other existing substrates.     

Optical properties of CdSe<Subscript>x</Subscript>Te<Subscript>1−x</Subscript> epitaxial films studied by spectroscopic ellipsometry

We have determined the dielectric constants for a series of CdSe_xTe_1−x thin films grown on Si substrates using a rotating-analyzer spectroscopic ellipsometer. Initially, the alloy concentration and the sample quality were determined using x-ray diffraction. A standard inversion technique was then used to obtain the dielectric constants from the measured ellipsometric spectra. Using these calculated absorption spectra, we were able to estimate the fundamental bandgap for these CdSe_xTe_1−x alloys. In addition, we also determined the dispersion of the indices of refraction as well as the critical points related to the higher-order electronic transitions for this alloy.     

The indices of refraction of molecular-beam epitaxy-grown Be<Subscript>x</Subscript>Zn<Subscript>1−x</Subscript>Te ternary alloys

We have used a combination of prism-coupling, reflectivity, and ellipsometric techniques to investigate the indices of refraction, n, of a series of Be_xZn_1−xTe thin films grown on InP substrates. After determining the concentrations of each of the Be_xZn_1−xTe alloys using x-ray diffraction measurements, we measured their n at discrete wavelengths using a prism-coupler setup. In addition, we used reflectivity measurements to complement the prism-coupler data and arrive at the dispersion relations of n for the Be_xZn_1−xTe alloys below their fundamental energy gaps. We then employed a rotating analyzer-spectroscopic ellipsometer to measure the complex reflection ratio for each of the films at angles of incidence of 65°, 70°, and 75°. By using the n values obtained from both the prism-coupler and the reflection-spectroscopy techniques to guide the ellipsometric analysis, we were able to obtain accurate results for the dispersion of n for the Be_xZn_1−xTe alloys, not only below their fundamental energy gaps, but also above their energy gaps (up to 6.5 eV) using these three complementary techniques.     

Quantization effects in digitally behaving circuit implementationsof Kohonen networks

Implementing a neural network on a digital or mixed analog and digital chip yields the quantization of the synaptic weights dynamics. This paper addresses this topic in the case of Kohonen's self-organizing maps. We first study qualitatively how the quantization affects the convergence and the properties, and deduce from this analysis the way to choose the parameters of the network (adaptation gain and neighborhood). We show that a spatially decreasing neighborhood function is far more preferable than the usually rectangular neighborhood function, because of the weight quantization. Based on these results, an analog nonlinear network, integrated in a standard CMOS technology, and implementing this spatially decreasing neighborhood function is then presented. It can be used in a mixed analog and digital circuit implementation.     

LAG WINDOW ESTIMATION OF THE DEGREE OF DIFFERENCING IN FRACTIONALLY INTEGRATED TIME SERIES MODELS

Abstract. In this paper we consider the estimation of the degree of differencing d in the fractionally integrated autoregressive moving-average time series model ARFIMA ( p, d, q ). Using lag window spectral density estimators we develop a regression type estimator of d which is easy to calculate and does not require prior knowledge of p and q. Some large sample properties of the estimator are studied and the performance of the estimator for small samples is investigated using the simulation method for a range of commonly used lag windows. Some practical recommendations on the choice of lag windows and the choice of the window parameters are provided.     

Lack of insulin feedback inhibition in non-obese and obese men

The existence of insulin feedback inhibition is a controversial issue. The present study adopted a novel approach to determine whether insulin feedback inhibition exists in vivo during physiologic hyperinsulinemia and if it could contribute to enhanced insulin secretion in obesity. Serial plasma insulin and C-peptide levels were determined during a basal state and a hyperinsulinemic clamp (287 pmol/min/m2) and following discontinuation of the insulin infusion under euglycemic conditions. Insulin secretion rates were derived from plasma C-peptide levels and individual C-peptide kinetics using a two-compartment model. Eight non-obese and nine obese men were recruited for the studies, which were performed in random order. Men with significant variations in glucose levels during hyperinsulinemia were excluded from the analysis. Plasma glucose levels were similar between the non-obese and obese groups during all phases of the study, and similar plasma insulin levels were achieved in both groups during euglycemic hyperinsulinemia. In obese men, C-peptide levels were significantly greater compared with non-obese men during euglycemic hyperinsulinemia (P < .05). However, neither the non-obese nor the obese group demonstrated significant suppression of insulin secretion rates during euglycemic hyperinsulinemia. Expressing the data in absolute terms or as a percent of basal did not alter the results. Moreover, there was no significant change between the non-obese and the obese group during the rapid onset and cessation of hyperinsulinemia. Under euglycemic conditions, physiologic hyperinsulinemia does not induce suppression of endogenous insulin secretion in non-obese or obese men.     

NapWell: An EOG-based Sleep Assistant Exploring the Effects of Virtual Reality on Sleep Onset

Virtual Reality - We present NapWell, a Sleep Assistant using virtual reality (VR) to decrease sleep onset latency by providing a realistic imagery distraction prior to sleep onset. Our proposed...