Assessing cortical functional connectivity by partial directed coherence: simulations and application to real data

The aim of this paper is to test a technique called partial directed coherence (PDC) and its modification (squared PDC; sPDC) for the estimation of human cortical connectivity by means of simulation study, in which both PDC and sPDC were studied by analysis of variance. The statistical analysis performed returned that both PDC and sPDC are able to estimate correctly the imposed connectivity patterns when data exhibit a signal-to-noise ratio of at least 3 and a length of at least 27 s of nonconsecutive recordings at 250 Hz of sampling rate, equivalent, more generally, to 6750 data samples.     

The effect of metal type on the sulfur tolerance of catalysts supported on niobia for sour water-gas shift reaction

Hydrogen production via water-gas shift (WGS) reaction using heavy oil residues as syngas source is an attractive way to improve refinery margin. However, this low cost syngas may present significant concentration of sulfur, leading to poisoning of usual WGS catalysts. Searching for sulfur tolerant catalysts, the performance of niobia supported platinum, gold and copper catalysts was evaluated under near-industrial conditions, in the absence and presence of H₂S. Cu/Nb₂O₅ catalyst was inactive, even under clean conditions. Au/Nb₂O₅ presented higher activity and complete deactivation when exposed to sulfur, but recovered its catalytic activity with the removal of H₂S from the reaction mixture, indicating a reversible deactivation. Pt/Nb₂O₅ catalyst was the most suitable among the catalysts evaluated to be used in sour conditions, not deactivating when exposed to 50 ppm and 1000 ppm of H₂S.     

Characterization of Silver fir Wood Decay Classes Using Sugar Metabolites Detected with Ion Chromatography

Hunter’s classification is the most adopted method for describing coarse woody debris (CWD) decay stages; however, wood chemical characterization is often lacking. This study explores the sugar profiles of living silver fir (Abies alba Mill.) trees and CWD samples in Hunter’s five-decay stages, evaluating the trends and variability in sugar content in CWD samples during decomposition. Wood cores from living trees and CWD samples from two different forest sites in Trentino (Italy) were analyzed after extraction using ion-exchange chromatography, equipped with pulsed amperometric and charge aerosol detectors (IC-PAD-CAD). Detailed monosaccharides, disaccharides, and sugar alcohol profiles of living wood and CWD samples were described. Cellobiose, arabinose, maltose, and trehalose showed similar trend in both the sites. Principal component analysis (PCA) highlighted the good capability of sugar profiles to well characterize and discriminate silver fir wood samples among Hunter’s categories of wood decomposition.     

Analysis of the dynamics of paste drying in a spouted bed

Although there are some models available in the literature for paste drying in spouted beds, few of them have focused on transient analysis of dynamical systems. Our objective was to integrate experiments and simulations of a dynamic model to investigate the transient response to disturbances and interruptions in the feed flow during paste drying in a spouted bed with inert particles. The spouted bed consisted of a cylindrical column with 50.0?cm of height and 20.0?cm of diameter. Drying tests were performed at inlet gas temperatures of 70?°C and 100?°C and inlet air flow 30% above the minimum spouting velocity. A 5% w/w suspension of calcium carbonate was used as paste material, and glass spheres of 2.2?mm were used as inert materials. Different patterns of step function changes were tested in the paste feed flow rate. A lumped parameter model was used to predict mass and heat transfer during the drying. Experiments and simulations were in good agreement.     

Emotional evaluation of lighting in university classrooms: A preliminary study

In educational environments an improvement in the quality of interior lighting has a direct benefit in increasing productivity and alertness of students and teachers, as well as very important implications for the energy efficiency of th eeducation facilities but when a replacement with different lighting is analyzed, research may be tarnished by users’ preformed opinions, influenced by manufacturers and advertising. Consequently, it is necessary to understand the users’ point of view, even before of being subjected to any change in the lighting stimulus. Based on the Kansei Engineering framework, the general objective of this paper is to evaluate and compare the subjective evaluation of students’ pre-formed opinions to lighting provided by two types of lamps (fluorescentandLED). The subjective assessment of 427 university students has been compared over four years. The results show significant differences in students’ subjective evaluation. This finding highlights the existence of symbolic or functional attributes of the usefulness perceived by the student that could influence on investigations in which different types of lighting are compared.     

The bovine colostrum microbiome and its association with clinical mastitis

In an effort to characterize colostrum microbial diversity and its potential associations with early-lactation clinical mastitis, we used high-throughput sequencing of the 16S rRNA gene to investigate the bovine colostrum microbiome. A prospective observational study was conducted that included 70 Holstein cows; colostrum samples were collected from all 4 mammary gland quarters. Colostrum samples were categorized according to whether the quarter was diagnosed (CMC) or not diagnosed (NCMC) with clinical mastitis during the first 30 d postpartum. Colostrum samples were dominated by Firmicutes, Bacteroidetes, Proteobacteria, Actinobacteria, Fusobacteria, and Tenericutes phyla, with the 6 most common taxa [order (o), family (f), and genus (g)] being g_Staphylococcus, g_Prevotella, f_Ruminococcaceae, o_Bacteroidales, o_Clostridiales, and g_Pseudomonas. The colostrum microbiota of primiparous cows was significantly richer (higher number of bacterial species) than that of multiparous cows, and differences in colostrum taxonomic structure between parities were also observed. The microbial community of NCMC samples of primiparous cows was significantly more diverse than that of CMC samples, and the relative abundances of the Tenericutes and Fusobacteria phyla as well as the Mycoplasma and Fusobacterium genera were significantly higher in NCMC than in CMC samples of primiparous cows. The colostrum core microbiome, defined as the bacterial taxa common to all colostrum samples examined, was composed of 20 taxa and included bacterial genera already known to be associated with mastitis (e.g., Staphylococcus, Mycoplasma, and Streptococcus spp.). Our results indicate that the colostrum microbiome of primiparous cows differs from that of multiparous cows, and it harbors some diversity and taxonomic markers of mammary gland health specific to primiparous cows only.     

Fermented goats’ milk produced with selected multiple starters as a potentially functional food

A screening among five lactic acid bacteria, used alone or in combination, led to select a mixed starter (Streptococcus thermophilus CR12, Lactobacillus casei LC01, Lactobacillus helveticus PR4, Lactobacillus plantarum 1288) capable to produce a fermented goats’ milk containing γ-aminobutyric acid (GABA) and angiotensin-I converting enzyme (ACE)-inhibitory peptides. The fermented milk was characterized by cell counts of lactic acid bacteria not lower than 7.0 log cfu g⁻¹, even after 45 days of storage at 4 °C. Fermentation of goats’ milk resulted in the production of ca. 28 mg kg⁻¹ of GABA. Furthermore the fermented goats’ milk had an in vitro ACE-inhibitory activity of ca. 73%. Prolonged cold storage did not significantly affect both the concentration of GABA and the ACE-inhibitory activity. Moreover, the taurine content did not significantly vary during both fermentation and the entire storage period.     

Effect of cellulose fibers addition on the mechanical properties and water vapor barrier of starch-based films

Starch-based films have promising application on food packaging, because of their environmental appeal, low cost, flexibility and transparency. Nevertheless, their mechanical and moisture barrier properties should be improved. The aim of this work was to enhance these properties by reinforcing the films with cellulose fibers. Besides, the influences of both the solubility coefficient of water in the films (β) and the diffusion coefficient of water vapor through the films (D^w) on the films' water vapor permeability (K^w) were investigated. Films were prepared by the so-called casting technique, from film-forming suspensions of cassava starch, cellulose fibers (1.2 mm long and 0.1 mm of diameter), glycerol and water. The influence of fibers addition on K^w was determined at three relative humidity gradient ranges, ΔRH (2–33%, 33–64% and 64–90%). Films reinforced with cellulose fibers showed higher tensile strength and lower deformation capacity, and presented lower K^w than films without fibers. K^w showed strong dependency of β and D^w, presenting values up to 2–3 times greater at ΔRH = 64–90% than at ΔRH = 33–64%, depending on the film formulation. Therefore, adding cellulose fibers to starch-based films is a viable alternative to improve their mechanical and water barrier properties. Besides, this work showed the importance of determining film's water vapor permeability simulating the real environmental conditions the film will be used.     

Analysis of trace elements in southern Italian wines and their classification according to provenance

Wines from three important wine-producing Southern Italian regions (Basilicata, Calabria and Campania) were characterized according to their content in macro-, micro-elements and lanthanides. The elemental composition was used in multivariate statistical analysis to discriminate the wines according to geographical origin. A total of 61 elements were determined in 120 red wines produced in the years 2000-2002, and precisely 40 samples for each region. Results indicated that element analysis provides a good prospect for discriminating wines by regions, even if the element composition is not dependent on the year of production of wine. A Canonical Variate Analysis showed that the discrimination of wines according to their provenance is based on the following elements: Ag, B, Ca, Cd, Eu, Fe, Ga, La, Lu, Mn, Nd, Pr, Sm, Th, Tm, V, Yb, and Zr for Basilicata; Al, B, Fe, Mg, Mn, Ti, Tl, Sc and Zn for Calabria; Ba, Eu, K, I, Rb, and Tl for Campania.