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51.
Alexandra C. Green Lena M. Lidfors Sabrina Lomax Livio Favaro Cameron E.F. Clark 《Journal of dairy science》2021,104(1):826-838
Mammalian vocalizations can encode contextual information in both the spectrographic components of their individual vocal units and in their temporal organization. Here we observed 23 Holstein-Friesian dairy cows immediately after birth during interactions with their calf and when their calf was separated to the other side of a fence line. We investigated whether the vocalizations emitted in these postpartum contexts would vary temporally. We also described the maternal and stress behaviors preceding and following postpartum vocal production using kinematic diagrams and characterized call sequence structure. The kinematic diagrams highlight the disruption of maternal responses caused by calf separation and show that behavioral and vocal patterns varied according to the cows' emotional states and proximity to the calf in both contexts. During calf interactions, cows mainly produced closed-mouth calls simultaneous to licking their calf, whereas an escalation of stress responses was observed during calf separation, with the cows approaching the fence line, becoming alert to the calf, and emitting more mixed and open-mouth calls. Call sequences were similarly structured across contexts, mostly containing repetitions of a single call type, with a mean interval of 0.57 s between calls and a greater cumulative vocalization duration, attributed to an increased number of vocal units per sequence. Overall, calf separation was associated with a greater proportion of calls emitted as a sequence (inverse of single isolated calls), a shorter interval between separate call sequences, and a greater number of vocal units per sequence, compared with calf interactions. These temporal vocal features varied predictably with the high stress expression from cows during calf separation and may represent temporal modulations of emotional expression. Despite the noisy farm soundscape, empirical call type and temporal vocal features were easy to measure; thus, findings could be applied to future cattle studies wishing to analyze vocalizations for on-farm welfare assessments. 相似文献
52.
Dr. Rebecca E. Moore Sabrina K. Spicer Julie A. Talbert Dr. Shannon D. Manning Dr. Steven D. Townsend Dr. Jennifer A. Gaddy 《Chembiochem : a European journal of chemical biology》2023,24(6):e202200643
Group B Streptococcus (GBS) is an encapsulated Gram-positive bacterial pathogen that causes severe perinatal infections. Human milk oligosaccharides (HMOs) are short-chain sugars that have recently been shown to possess antimicrobial and anti-biofilm activity against a variety of bacterial pathogens, including GBS. We have expanded these studies to demonstrate that HMOs can inhibit and dismantle biofilm in both invasive and colonizing strains of GBS. A cohort of 30 diverse strains of GBS were analyzed for susceptibility to HMO-dependent biofilm inhibition or destruction. HMOs were significantly effective at inhibiting biofilm in capsular-type- and sequence-type-specific fashion, with significant efficacy in CpsIb, CpsII, CpsIII, CpsV, and CpsVI strains as well as ST-1, ST-12, ST-19, and ST-23 strains. Interestingly, CpsIa as well as ST-7 and ST-17 were not susceptible to the anti-biofilm activity of HMOs, underscoring the strain-specific effects of these important antimicrobial molecules against the perinatal pathogen Streptococcus agalactiae. 相似文献
53.
Reginaldo Muccillo Sabrina G. M. Carvalho Rafael L. Denaldi Eliana N. S. Muccillo 《International Journal of Applied Ceramic Technology》2023,20(2):951-958
Molten Na2CO3–K2CO3 (NKC, 56–44 mol%) eutectic compositions were vacuum-impregnated, at the eutectic temperature, into two porous ZrO2:8.6 mol% MgO (magnesium-partially stabilized zirconia, MgPSZ) and ZrO2:8 mol% Y2O2 (yttria-fully stabilized zirconia, 8YSZ) ceramics. Thermogravimetric analyses were performed in mixtures of that composition with MgPSZ and 8YSZ ceramic powders. Before impregnation, porosity was achieved in the two compounds by addition and thermal removal of 30 vol.% NKC. To ascertain the carbonates had filled up through the ceramic body, both sides of the parallel and fracture surfaces of the disk-shaped impregnated compositions were observed in a scanning electron microscope and analyzed by energy-dispersive X-ray spectroscopy. The electrical conductivity of the two ceramics, before and after impregnation, was evaluated by electrochemical impedance spectroscopy in the 5 Hz–13 MHz frequency range from approximately 530 to 740°C. The permeation of the carbonate ions through the membranes via the eutectic composition was assessed by the threshold temperatures of the onset of the carbonate ion percolation. The objectives were to prepare dual-phase membranes for the separation of carbon dioxide and for the development of carbon dioxide sensors. 相似文献
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Concentrations and determinants of organochlorine levels among pregnant women in Eastern Spain 总被引:1,自引:0,他引:1
Sabrina Llop Ferran Ballester Esther Vizcaino Maria-Jose Lopez-Espinosa Marisa Rebagliato Alfredo Marco Joan O. Grimalt 《The Science of the total environment》2010,408(23):5758-5767
Persistent organic pollutants (POPs) comprise a large variety of toxic substances with ample distribution. While exposure to these toxins occurs mainly through diet, maternal POP levels may be influenced by certain sociodemographic, environmental, or lifestyle factors. This is important given that these substances may have adverse effects on fetal development. The aim of this study is to examine the sociodemographic, environmental, lifestyle, and dietary determinants of the levels of hexachlorobenzene (HCB), b-hexachlorocyclohexane (b-HCH), 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (4,4′-DDT), 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene (4,4′-DDE), and polychlorinated biphenyls (PCB congeners 118, 138, 153, 180) measured in the blood of pregnant women participating in a mother-child cohort study conducted in Valencia (Spain).The study population consisted of 541 pregnant women who formed part of the INMA (Childhood and the Environment) cohort (2004-2006). POP levels were determined in blood taken during the 12th week of pregnancy with the aid of gas chromatography with electron capture detection. Sociodemographic, environmental, and dietary information was obtained from a questionnaire. Multivariate Tobit regression models were constructed in order to assess the association between POP levels and selected covariates.The results showed that all the women had detectable levels of at least one of these compounds while in 43% of the subjects, all eight compounds were detected. The compounds found in the greatest number of women were 4,4′-DDE (100%) and PCBs 153 and 180 (95%). The most important determinants of high POP levels were the mother's age, country of origin, increased body mass index, and number of weeks of breastfeeding after previous pregnancies. With regard to diet, 4,4′-DDT and 4,4′-DDE levels increased with the intake of meat, fruit, and cereal. PCB 153 levels increased with the intake of seafood. The levels of HCB, b-HCH, 4,4′-DDT, and 4,4′-DDE observed in this study were slightly higher than in other studies, whereas the PCB levels were similar. 相似文献
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57.
Caroline Scholtes Sabrina Nizet Sonia Collin 《Journal of the Institute of Brewing》2012,118(2):223-229
The typical Belgian Gueuze beers are produced with aged hop from a grist of malt and wheat, according to a very long oxidation process (extended boiling, cooling overnight in an open‐air container, oak‐barrel ageing). Two theaspirane‐oxidation‐derived products, dihydrodehydro‐β‐ionone and 4‐hydroxy‐7,8‐dihydro‐β‐ionone, are evidenced here for the first time in Gueuze beers. Both compounds have been recently identified in oxidative wines such as Jura Flor‐Sherry and Sauternes wines. Another analogy with Jura Flor‐Sherry wines was the presence of the nutty/curry odorants sotolon and abhexon, although at lower concentrations. Copyright © 2012 The Institute of Brewing & Distilling 相似文献
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59.
Life tasks serve as an avenue for individuals to give personal meaning to their lives and to organize personal effort and activities. The present data, from a longitudinal study of the transition to college life, demonstrate how construals of life tasks can help to illuminate individuals' activity choices and affective experience of daily life activities. Ss who were absorbed in the task of "being on my own, away from family," also invested their academic activities with special significance. They experienced more stress and less satisfaction from their (considerable) academic accomplishments than did those who framed their tasks in more concrete terms. Experience-sampling data showed that activity choices followed from life task concerns, even when such activities were particularly anxiety-provoking. Discussion considers how similar life task themes may be enacted differently in other contexts. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
60.
Bruno Apolloni Simone Bassis Alberto Clivio Sabrina Gaito Dario Malchiodi 《Natural computing》2007,6(1):33-53
We propose an aging mechanism which develops in artificial bacterial populations fighting against antibiotic molecules. The
mechanism is based on very elementary information gathered by each individual and elementary reactions as well. Though we
do not interpret the aging process in strictly biological terms, it appears compliant with recent studies on the field, and
physically feasible. The root of the aging mechanism is an adaptation strategy based on a thresholding operation that derives
from theoretical results on stochastic monotone games. The methods for implementing it denote their rationale in that they
represent a sophisticated dialect of pi-calculus, a widespread computational paradigm for implementing dynamics of massive
populations with bipolar reactions. As a result we may implement processes that explain some typical patterns of the evolution
of the immunosystems. 相似文献