On some limitations of probabilistic models for dimension-reduction: illustration in the case of one particular probabilistic formulation of PLS

Partial Least Squares (PLS) refer to a class of dimension-reduction techniques aiming at the identification of two sets of components with maximal covariance, in order to model the relationship between two sets of observed variables $x\in\mathbb{R}^p$ and $y\in\mathbb{R}^q$, with $p\geq 1, q\geq 1$. El Bouhaddani et al. (2017) have recently proposed a probabilistic formulation of PLS. Under the constraints they consider for the parameters of their model, this latter can be seen as a probabilistic formulation of one version of PLS, namely the PLS-SVD. However, we establish that these constraints are too restrictive as they define a very particular subset of distributions for $(x,y)$ under which, roughly speaking, components with maximal covariance (solutions of PLS-SVD), are also necessarily of respective maximal variances (solutions of the principal components analyses of $x$ and $y$, respectively). Then, we propose a simple extension of el Bouhaddani et al.'s model, which corresponds to a more general probabilistic formulation of PLS-SVD, and which is no longer restricted to these particular distributions. We present numerical examples to illustrate the limitations of the original model of el Bouhaddani et al. (2017)

Further insights into the floral character of Touriga Nacional Wines

Higher-quality Touriga Nacional (TN) wines are characterized by a fruity-citric aroma described as sweet and fresh citrus evoking the bergamot fruit (Citrus bergamia). In fact, “bergamot-like” descriptor is currently employed to rate higher quality TN wines. The aim of thiswork was to identify among volatile compounds present in bergamot fruit extracts (mainly terpenes) which of them contributes the most to the bergamot overall perception, and relate these data with the volatile composition of TN wines. The identification of the most important descriptors was done by sensory analysis. Among 18 descriptors 3were selected: bergamot-like aroma, orange like, and violet. A GCO of a typical TN wine extract allows the identification of 3 related odorant zones ZO1, ZO2, and ZO3 related with bergamot-like aroma. Using AEDA, ZO2 was confirmed to be one of the most important odorant zones. Using AEDA the presence of linalool and linalyl acetate was confirmed. A similarity test was performedwith a non-TN wine added with linalool and linalyl acetate alone or in combinations. The highest similarity value was observed when linalool (SV = 5.9) was added. In fact, results obtained from the analysis of several red wines from different varieties show that terpenols are present in higher amounts in wines coming from TN variety, which proves that these compounds can be the clue to the varietal aroma of TN wines

The centrosome protein NEDD1 as a potential pharmacological target to induce cell cycle arrest

<p>Abstract</p> <p>Background</p> <p>NEDD1 is a protein that binds to the gamma-tubulin ring complex, a multiprotein complex at the centrosome and at the mitotic spindle that mediates the nucleation of microtubules.</p> <p>Results</p> <p>We show that NEDD1 is expressed at comparable levels in a variety of tumor-derived cell lines and untransformed cells. We demonstrate that silencing of NEDD1 expression by treatment with siRNA has differential effects on cells, depending on their status of p53 expression: p53-positive cells arrest in G1, whereas p53-negative cells arrest in mitosis with predominantly aberrant monopolar spindles. However, both p53-positive and -negative cells arrest in mitosis if treated with low doses of siRNA against NEDD1 combined with low doses of the inhibitor BI2536 against the mitotic kinase Plk1. Simultaneous reduction of NEDD1 levels and inhibition of Plk1 act in a synergistic manner, by potentiating the anti-mitotic activity of each treatment.</p> <p>Conclusion</p> <p>We propose that NEDD1 may be a promising target for controlling cell proliferation, in particular if targeted in combination with Plk1 inhibitors.</p

Rootstocks effect on volatile composition of Albariño wines

Rootstock is a viticultural practice used to combat the devastating Phylloxera vitifoliae (Fitch). Additionally, it is well-known that wine aroma composition depends mainly on variety, viticulture management and winemaking; therefore, rootstocks can affect to berry quality. This study evaluated the influence of nine rootstocks (110R, SO4, 196-17C, Riparia G, 161-49C, 420A, Gravesac, 3309C and 41B) on volatile composition of Albariño wine in two consecutive vintages. Material and Methods: Volatile compounds belonging to eight groups (alcohols, C6-compounds, ethyl esters+acetates, terpenes + C13-norisoprenoids, volatile phenols, volatile acids, lactones and carbonyl compounds) were determined in Albariño wines by GCMS, during 2009 and 2010 vintages. Results: Rootstock 110R had a positive influence on Albariño wines, increasing total volatile concentration, due mainly to 2-phenylethanol, decanoic and hexanoic acids, ethyl esters and acetates, and C13-norisoprenoids. However, the higher contribution of volatile fatty acids to Albariño wine was shown when grapevines were grafted onto SO4. Conclusions: This work provides new information about the impact of rootstocks on Albariño wine volatile composition, where 110R had a positive influence on Albariño wines under the edaphoclimatic conditions of Salnés Valley (Galicia, Spain).This research was funded by Xunta de Galicia (PGIDIT06RAG018E) and by the Portuguese Foundation for Science and Technology (FCT), under the scope of the strategic funding of UIDB/04469/2020 unit.info:eu-repo/semantics/publishedVersio

Perceptual processing strategy and exposure influence the perception of odor mixtures

In flavor perception, both experience with the components of odor/taste mixtures and the cognitive strategy used to examine the interactions between the components influence the overall mixture perception. However, the effect of these factors on odor mixtures perception has never been studied. The present study aimed at evaluating whether 1) previous exposure to the odorants included in a mixture or 2) the synthetic or analytic strategy engaged during odorants mixture evaluation determines odor representation. Blending mixtures, in which subjects perceived a unique quality distinct from those of components, were chosen in order to induce a priori synthetic perception. In the first part, we checked whether the chosen mixtures presented blending properties for our subjects. In the second part, 3 groups of participants were either exposed to the odorants contributing to blending mixtures with a "pineapple" or a "red cordial" odor or nonexposed. In a following task, half of each group was assigned to a synthetic or an analytical task. The synthetic task consisted of rating how typical (i.e., representative) of the target odor name (pineapple or red cordial) were the mixtures and each of their components. The analytical task consisted of evaluating these stimuli on several scales labeled with the target odor name and odor descriptors of the components. Previous exposure to mixture components was found to decrease mixture typicality but only for the pineapple blending mixture. Likewise, subjects engaged in an analytical task rated both blending mixtures as less typical than did subjects engaged in a synthetic task. This study supports a conclusion that odor mixtures can be perceived either analytically or synthetically according to the cognitive strategy engaged

Hemoprotozoa of domestic animals in France: Prevalence and molecular characterization

Very limited information is available on epizootiology of haematozoan infections in French domestic animals. In an attempt to address this issue, prevalence of piroplasmida was studied in carnivores and ruminants, whereas prevalence of Hepatozoon spp. was only investigated in carnivores. In total, 383 animals were included in the survey (namely 116 cats, 108 dogs, 91 sheep and 68 cows). Parasite diagnosis was carried out using molecular methods such as PCR and sequencing of the 18S rRNA gene. In addition, ruminant samples were analyzed with the reverse line blotting technique (RLB). Results of RLB and PCR plus sequencing were in total agreement. In carnivores, haematozoan prevalence was close to 1%. Two cats were infected by H. canis (1.7% prevalence) and one of them was co-infected by Cytauxzoon sp. (0.8%). This represents the first finding of both pathogens in French cats. One dog was infected by H. canis (0.9%) and another by Babesia canis vogeli (0.9%). In ruminants, haematozoan prevalence (piroplasmida) was significantly higher than in carnivores (4.8% in sheep and 8.8% in cow). Theileria ovis was found in 1 sheep, Theileria sp. in 2 sheep, Theileria buffeli in 5 cows and B. major in 1 cow. Evidence presented in this contribution indicates that haematic protozoa are not widely distributed in domestic mammal populations of France

Chemo-sensory approach for the identification of chemical compounds driving green character in red wines

The present work seeks to define the “green character” of red wines and characterise the groups of molecules potentially involved in that perception. Fifty-four wines were screened by wine experts for different levels of green character. Six different phenolic fractions were obtained by liquid chromatography (LC) and further submitted to sensory and chemical characterisation. The volatile fraction was screened by semipreparative LC, Gas Chromatography-Olfactometry (GC-O) and quantitative analysis. The green character was linked to vegetal aroma, astringency, green and dry tannins according to experts of the Somontano region. Non-volatile fractions containing tannins with mean degree of polymerisation of ten and smaller anthocyanin-derivative pigments (<tetramers) imparted astringency-related sensations such as dryness and stickiness, respectively. No specific aroma compounds were identified in the GC-O study of green wines, however the wines contained significantly higher levels of fusel alcohols. The interaction between isoamyl alcohol and the anthocyanin-derivative fraction and/or tannins is suggested to be involved in the formation of green character in red wines