Effects of temperature, ammonium and glucose concentrations on yeast growth in a model wine system

In enology, alcoholic fermentation is a complex process involving several mechanisms. Slow and incomplete alcoholic fermentation is a chronic problem for the wine industry and factors leading to sluggish and stuck fermentations have been extensively studied and reviewed. The most studied cause of sluggish and stuck fermentation is the nitrogen content limitation. Nevertheless, other factors, such as temperature of fermentation and sugar concentration can affect the growth of yeasts. In this study we modelled the yeast growth‐cycle in wine model system as a function of temperature, sugar and ammonium concentrations; the individual effects and the interaction of these factors were analysed by means of a quadratic response surface methodology. Cell concentrations and weight loss were monitored in the whole wine fermentation process. The results of central composite design show that lower is the availability of nitrogen, higher is the cell growth rate; moreover, initial nitrogen concentration also influences survival time of Saccharomyces cerevisiae.     

Object Retrieval in the 1st Year of Life: Learning Effects of Task Exposure and Box Transparency.

Before 12 months of age, infants have difficulties coordinating and sequencing their movements to retrieve an object concealed in a box. This study examined (a) whether young infants can discover effective retrieval solutions and consolidate movement coordination earlier if exposed regularly to such a task and (b) whether different environments, indexed by box transparency, would impact the rate of learning and time of discovery of these solutions. Infants (N=12) were presented with an object retrieval task every week from 6 1/2 months of age until they were able to retrieve the toy from the box using coordinated two-handed patterns for 3 weeks. To reach that criterion, infants tested with an opaque box took 2 1/2 months and infants tested with a semitransparent box took 1 1/2 months. Both groups outperformed age-matched controls who received a one-time exposure to the task. Repeated exposure to the task and vision of the toy significantly enhanced this process of solution discovery. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Broadband frequency-domain electromagnetic analysis and automatic extraction of Spice-compatible equivalent circuits

A very simple and effective algorithm able to predict the frequency response of a multiport device over a wide band, starting from the electromagnetic analysis at some spot frequencies, is derived. Data obtained by the proposed procedure are further processed to extract a Foster's type, lumped element, equivalent circuit, suitable for use as a Spice model of the device.     

On the derivation of coupled-line models from EM simulators and application to MoM analysis

This paper addresses the problem of deriving an actual coupled-line model from the "spot frequency" characteristics of transmission media derived by means of a numerical electromagnetic simulator. For a given set of coupled lines, possibly asymmetric and lossy, one of the main issues is to recover a model whose parameters are physically and practically meaningful. In order to satisfy the requirements, the model ought to basically yield a natural generalization of the well-known even/odd and c//spl pi/ modes for couples of lines, and collapse to a set of uncoupled lines when coupling is negligible. Hence, part of this study is devoted to discussing and evaluating models that satisfy such requirements. The end result is a Weissfloch-type equivalent circuit made up of uncoupled lines and input and output ideal transformers. The algorithm is then applied to the network parameters of coupled lines. The latter are evaluated by a full-wave method of moments approach, and a subsequent short-open calibration (SOC) procedure. Finally, a new algorithm is introduced that is able to evaluate and remove the contribution of the naked discontinuity due to ports, usually not directly available from the SOC routine.     

Practical design of a high-power tuning-less W-band triplexer for ground radar surveillance systems

The design of a rectangular waveguide 95 GHz (W-band) triplexer for ground radar systems is presented. The triplexer comprises three in-line filters with inductive irises as coupling elements and a manifold formed by three T-junctions. In particular, the scheme proposed is aimed at handling large powers and reducing losses. The triplexer was assembled and measured, showing very good agreement with the simulated results.     

Immunohistochemical expression of p53 and c-erbB-2 in breast carcinoma: relation with epidemiologic factors, histologic features and prognosis

We have performed immunohistochemical staining for p53 and c-erbB-2 on formaldehyde-fixed, paraffin-embedded primary invasive ductal carcinomas from 112 patients, with a minimal follow-up time of 60 months. All of them had received postoperative chemoradiation therapy. We have analyzed the association of these factors with epidemiologic risk factors, histopathologic features and hormonal receptor status and the influence on prognosis. Our results indicate that the expression of c-erbB-2 protein defines a group of node-negative patients with poor prognosis. The overexpression of c-erbB-2 has shown a significant association with estrogen receptor status (those tumors expressing c-erbB-2 are usually estrogen receptor negative), presence of fibrosis and lymphoplasmacytoid infiltrates. P53 expression has shown no relation either with prognosis or with any other histopathologic or clinical feature. The only factors with prognostic influence in our series have been tumor size, the presence of node metastases, TNM stage and the prognostic morphometric index (Baak's index), apart from c-erbB-2 in node-negative patients. However, only the TNM stage showed an independent association with prognosis after a multivariate analysis. In summary, in our experience the expression of p53 protein has no prognostic influence on breast carcinoma, and TNM stage remains to be as the most powerful prognostic factor in these patients.     

Network regression with predictive clustering trees

Network data describe entities represented by nodes, which may be connected with (related to) each other by edges. Many network datasets are characterized by a form of autocorrelation, where the value of a variable at a given node depends on the values of variables at the nodes it is connected with. This phenomenon is a direct violation of the assumption that data are independently and identically distributed. At the same time, it offers an unique opportunity to improve the performance of predictive models on network data, as inferences about one entity can be used to improve inferences about related entities. Regression inference in network data is a challenging task. While many approaches for network classification exist, there are very few approaches for network regression. In this paper, we propose a data mining algorithm, called NCLUS, that explicitly considers autocorrelation when building regression models from network data. The algorithm is based on the concept of predictive clustering trees (PCTs) that can be used for clustering, prediction and multi-target prediction, including multi-target regression and multi-target classification. We evaluate our approach on several real world problems of network regression, coming from the areas of social and spatial networks. Empirical results show that our algorithm performs better than PCTs learned by completely disregarding network information, as well as PCTs that are tailored for spatial data, but do not take autocorrelation into account, and a variety of other existing approaches.     

The Landscape of microRNAs in βCell: Between Phenotype Maintenance and Protection

Diabetes mellitus is a group of heterogeneous metabolic disorders characterized by chronic hyperglycaemia mainly due to pancreatic β cell death and/or dysfunction, caused by several types of stress such as glucotoxicity, lipotoxicity and inflammation. Different patho-physiological mechanisms driving β cell response to these stresses are tightly regulated by microRNAs (miRNAs), a class of negative regulators of gene expression, involved in pathogenic mechanisms occurring in diabetes and in its complications. In this review, we aim to shed light on the most important miRNAs regulating the maintenance and the robustness of β cell identity, as well as on those miRNAs involved in the pathogenesis of the two main forms of diabetes mellitus, i.e., type 1 and type 2 diabetes. Additionally, we acknowledge that the understanding of miRNAs-regulated molecular mechanisms is fundamental in order to develop specific and effective strategies based on miRNAs as therapeutic targets, employing innovative molecules.     

The GAUGAA Motif Is Responsible for the Binding between circSMARCA5 and SRSF1 and Related Downstream Effects on Glioblastoma Multiforme Cell Migration and Angiogenic Potential

Circular RNAs (circRNAs) are a large class of RNAs with regulatory functions within cells. We recently showed that circSMARCA5 is a tumor suppressor in glioblastoma multiforme (GBM) and acts as a decoy for Serine and Arginine Rich Splicing Factor 1 (SRSF1) through six predicted binding sites (BSs). Here we characterized RNA motifs functionally involved in the interaction between circSMARCA5 and SRSF1. Three different circSMARCA5 molecules (Mut1, Mut2, Mut3), each mutated in two predicted SRSF1 BSs at once, were obtained through PCR-based replacement of wild-type (WT) BS sequences and cloned in three independent pcDNA3 vectors. Mut1 significantly decreased its capability to interact with SRSF1 as compared to WT, based on the RNA immunoprecipitation assay. In silico analysis through the “Find Individual Motif Occurrences” (FIMO) algorithm showed GAUGAA as an experimentally validated SRSF1 binding motif significantly overrepresented within both predicted SRSF1 BSs mutated in Mut1 (q-value = 0.0011). U87MG and CAS-1, transfected with Mut1, significantly increased their migration with respect to controls transfected with WT, as revealed by the cell exclusion zone assay. Immortalized human brain microvascular endothelial cells (IM-HBMEC) exposed to conditioned medium (CM) harvested from U87MG and CAS-1 transfected with Mut1 significantly sprouted more than those treated with CM harvested from U87MG and CAS-1 transfected with WT, as shown by the tube formation assay. qRT-PCR showed that the intracellular pro- to anti-angiogenic Vascular Endothelial Growth Factor A (VEGFA) mRNA isoform ratio and the amount of total VEGFA mRNA secreted in CM significantly increased in Mut1-transfected CAS-1 as compared to controls transfected with WT. Our data suggest that GAUGAA is the RNA motif responsible for the interaction between circSMARCA5 and SRSF1 as well as for the circSMARCA5-mediated control of GBM cell migration and angiogenic potential.