Phase portraits of Abel quadratic differential systems of second kind with symmetries

We provide normal forms and the global phase portraits on the Poincaré disk of the Abel quadratic differential equations of the second kind having a symmetry with respect to an axis or to the origin. Moreover, we also provide the bifurcation diagrams for these global phase portraits.     

Microtubule Destabilizing Sulfonamides as an Alternative to Taxane-Based Chemotherapy

Pan-Gyn cancers entail 1 in 5 cancer cases worldwide, breast cancer being the most commonly diagnosed and responsible for most cancer deaths in women. The high incidence and mortality of these malignancies, together with the handicaps of taxanes—first-line treatments—turn the development of alternative therapeutics into an urgency. Taxanes exhibit low water solubility that require formulations that involve side effects. These drugs are often associated with dose-limiting toxicities and with the appearance of multi-drug resistance (MDR). Here, we propose targeting tubulin with compounds directed to the colchicine site, as their smaller size offer pharmacokinetic advantages and make them less prone to MDR efflux. We have prepared 52 new Microtubule Destabilizing Sulfonamides (MDS) that mostly avoid MDR-mediated resistance and with improved aqueous solubility. The most potent compounds, N-methyl-N-(3,4,5-trimethoxyphenyl-4-methylaminobenzenesulfonamide 38, N-methyl-N-(3,4,5-trimethoxyphenyl-4-methoxy-3-aminobenzenesulfonamide 42, and N-benzyl-N-(3,4,5-trimethoxyphenyl-4-methoxy-3-aminobenzenesulfonamide 45 show nanomolar antiproliferative potencies against ovarian, breast, and cervix carcinoma cells, similar or even better than paclitaxel. Compounds behave as tubulin-binding agents, causing an evident disruption of the microtubule network, in vitro Tubulin Polymerization Inhibition (TPI), and mitotic catastrophe followed by apoptosis. Our results suggest that these novel MDS may be promising alternatives to taxane-based chemotherapy in chemoresistant Pan-Gyn cancers.     

The Peculiar Structure of Acetobacter pasteurianus CIP103108 LPS Core Oligosaccharide

Acetobacter pasteurianus, a member of the Alphaproteobacteria, is an acetic acid-producing bacterium present on sugar-rich substrates such as such as fruits, flowers and vegetables and traditionally used in the production of fermented food. The preferred living habitat associated with acid conditions makes the structure of the bacterial cell wall interesting to study, due to expected uncommon features. We have used a combination of chemical, analytical and NMR spectroscopy approaches to define the complete structure of the core oligosaccharide from A. pasteurianus CIP103108 LPS. Interestingly, the core oligosaccharide displays a high concentration of negatively charged groups, structural features that might contribute to reinforcing the bacterial membrane.     

Characterization of precipitates formed in X7R 0603 BME-MLCC during sintering

In the current study two different batches of X7R-0603 BME-MLCCs displayed dissimilar electrical performance, despite having the same chemical composition, tape casting, and sintering conditions; with the only difference between them being the ore deposits where the raw materials were extracted from to synthesize the BaTiO₃. Specifically, they presented different electrical response to highly accelerated life tests (HALT). Although the chemical analysis of each slip showed the same composition, the trace elements of the BaTiO₃ sources could have acted as dopants or produced different secondary phases. A search for precipitates in the two samples was conducted by means of Scanning (SEM) and Transmission Electron Microscopy (TEM) techniques. SEM observations confirmed the presence of precipitates formed within the structure of the MLCCs exhibiting the greatest decrement in their electrical resistance results during the HALT. In order to further characterize the observed precipitates, samples were prepared by Focused Ion Beam (FIB) lift-out method, to make TEM characterization of specific precipitates feasible. TEM studies were performed on the precipitates to obtain electron diffraction patterns and complementary Energy Dispersive X-Ray Spectroscopy (EDXS) chemical analysis. Based on the crystal and chemical data obtained, it can be concluded that the precipitates are a hexagonal anhydrous silicate oxyapatite phase with a stoichiometry of Ca₃Y₁₆Si₁₀O₁₃, and lattice parameters of a = 0.9353 nm and c = 0.6970 nm; this phase was not found in the JCPDS data base. Differences in raw materials coming from different ore deposits can produce undesired precipitates that affect the electrical performance of MLCCs.     

Short-term liveweight changes of dairy cows measured by stationary and walk-over weighing scales

Monitoring and detecting individual cows' liveweight (LW) and liveweight change (LWC) are important for estimation of nutritional requirements and health management, and could be useful to measure short-term feed intake, water consumption, defecation, and urination. Walk-over weighing (WOW) systems can facilitate measurements of LW for these purposes, providing automated LW recorded at different times of the day. We conducted a field study to (1) quantify the contribution of feed and water intake, as well as urine and feces excretions, to short-term LWC and (2) determine the feasibility of stationary and WOW scales to detect subtle changes in LW as a result of feed and water intake, urination, and defecation. In this experiment, 10 cows walked through a WOW system and then stood individually on a stationary scale collecting weights at 10 and 3.3 Hz, respectively. Cows were offered 4 kg of feed and 10 kg of water on the stationary scale. For each animal, LW before and after eating and drinking was then calculated using different approaches. Liveweight change was calculated as the difference between the initial and final LW before and after eating and drinking for each statistical measure. The weights of feed intake, water consumption, urination, and defecation were measured and used as predictors of LWC. Urine and feces were collected from individual cows while the cow was on the scale, using a container, and weighed separately. The agreement between LWC measured using either stationary or WOW scales was assessed to determine the sensitivity of the scales to detect subtle changes in LW using the coefficient of determination (R²), Lin's concordance correlation coefficient (CCC), and mean bias. The prediction model showed that most of the regression coefficients were not significantly different from +1.0 for feed and water, or ?1.0 for urine and feces. The R² and CCC values demonstrated a satisfactory agreement between calculated and stationary LWC and values ranged from 0.60 to 0.92 and 0.71 to 0.94, respectively. A moderate agreement was achieved between calculated and automated LWC with R² and Lin's CCC values of 0.45 to 0.63 and 0.60 to 0.74, respectively. Therefore, results demonstrated that new algorithms and data processing methods need to be continuously explored and improved to obtain accurate measurements of LW to measure changes in LW, especially from WOW scales.     

A dimensional reduction approach to modulate the core ruminal microbiome associated with methane emissions via selective breeding

The rumen is a complex microbial system of substantial importance in terms of greenhouse gas emissions and feed efficiency. This study proposes combining metagenomic and host genomic data for selective breeding of the cow hologenome toward reduced methane emissions. We analyzed nanopore long reads from the rumen metagenome of 437 Holstein cows from 14 commercial herds in 4 northern regions in Spain. After filtering, data were treated as compositional. The large complexity of the rumen microbiota was aggregated, through principal component analysis (PCA), into few principal components (PC) that were used as proxies of the core metagenome. The PCA allowed us to condense the huge and fuzzy taxonomical and functional information from the metagenome into a few PC. Bivariate animal models were applied using these PC and methane production as phenotypes. The variability condensed in these PC is controlled by the cow genome, with heritability estimates for the first PC of ~0.30 at all taxonomic levels, with a large probability (>83%) of the posterior distribution being >0.20 and with the 95% highest posterior density interval (95%HPD) not containing zero. Most genetic correlation estimates between PC1 and methane were large (≥0.70), with most of the posterior distribution (>82%) being >0.50 and with its 95%HPD not containing zero. Enteric methane production was positively associated with relative abundance of eukaryotes (protozoa and fungi) through the first component of the PCA at phylum, class, order, family, and genus. Nanopore long reads allowed the characterization of the core rumen metagenome using whole-metagenome sequencing, and the purposed aggregated variables could be used in animal breeding programs to reduce methane emissions in future generations.     

How to Prevent Flow Failures in Tailings Dams

Based on research carried out at 67 tailings dams in Spain: (1) tailings dams contain alternating sedimentary layers with contractive and dilative geomechanical behaviours; (2) tailings saturate quickly but drain more than 10 times slower due to the high-suction capacity of the porous sediments (2–300 MPa); and (3) over the long-term, a stationary flow regime is attained within a tailings basin. Four temporal and spatial conditions must all be present for a tailing dams flow failure to occur: (1) the tailings must experience contractive behaviour; (2) the tailings must be fully saturated; (3) the effective stress due to static or dynamic load must approach zero; and (4) the shear stress must exceed the tailings residual shear stress. Our results also indicate that the degree of saturation (S_r) is the most influential factor controlling dam stability. The pore-pressure coefficient controls geotechnical stability: when it exceeds 0.5 (S_r = 0.7), the safety factor decreases dramatically. Therefore, controlling the degree of tailings saturation is instrumental to preventing dam failures, and can be achieved using a double drainage system, one for the unconsolidated foundation materials and another for the overlying tailings.

     

Influence of the type of calcium salt on the cation absorption and firmness of black ripe olives

The preservation of olives intended for processing as black ripe olives must be done in a salt-free environment although it involves the use of calcium addition to retard olive softening. Calcium chloride and calcium lactate were added by up to 1600 mg Ca L⁻¹ (i) in the preservation liquid of olives before darkening and (ii) in the cover packing brine. The highest texture and calcium absorption were found in the latter case. In addition, the sensory characteristics of the final product were not affected by the use of any of the calcium salts studied at concentrations of up to 1600 mg Ca L⁻¹. Calcium chloride and calcium lactate can be employed to obtain higher texture and calcium content in black ripe olives, although it is advisable to add the cation to the cover packing brine of pitted olives rather than to the preservation liquid.     

Effect of processing on the microbiological quality and safety of chicken carcasses at slaughterhouse

Microbiological contamination of chicken meat depends on the conditions under which the animals are reared, slaughtered and processed. The aim of this study was to determine the influence of farm origin and processing stages at slaughterhouse on the microbial safety and quality of chicken. Samples of chicken carcasses from three different farms were taken from a slaughterhouse. Mesophiles, Escherichia coli, coagulase positive Staphylococcci counts, presence of Listeria monocytogenes,Campylobacter and Salmonella were determined at five sampling points: after defeathering, after evisceration, after washing, after chilling and after cutting. Chilling reduced log numbers of mesophiles, coagulase positive Staphylococci and E. coli by 0.85, 1.52 and 2.2 log units, respectively. Salmonella was not detected after chilling. High prevalence of Campylobacter spp was observed at all the stages ranging between 84% and 100%. L. monocytogenes was not detected in chicken carcasses after defeathering. However, it was detected after evisceration and after washing and chilling. The most critical stage for L. monocytogenes contamination was the portioning operation, the prevalence in breast and legs being 88% and 84%, respectively.