353 research outputs found

    On the effect of the temperature-humidity index on buffalo bulk milk composition and coagulation traits

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    Little is known about the effects of high levels of environmental temperature and humidity on milk yield and quality in buffaloes since this species is known to be more heat tolerant than cattle. However, the distribution of sweat glands and the dark skin color can negatively affect heat tolerance. Moreover, due to increased global temperatures, concerns regarding heat stress and thermoregulation in dairy animals, including buffaloes, have been extended to the northern hemisphere. In this study, the effects of both the temperature-humidity index (THI) and the maximum daily temperature-humidity index (MTHI) were estimated on bulk milk traits, namely fat, protein, lactose, urea content, pH levels, somatic cell score, coagulation properties, and bacteria count. The dataset consisted of repeated data from 99 Mediterranean water buffalo farms, and mixed models were used for the analyses. Supporting the negative correlations observed, bulk milk fat, protein, and lactose content were significantly lower when THI and MTHI were higher. Similarly, milk pH was lower when THI and MTHI were high; however, high levels of THI or MTHI seemed to not be markedly associated with the milk’s coagulation ability. According to both analysis of variance and correlations, the somatic cell score was not significantly affected by the THI and MTHI. This is the first study based on a large dataset that evaluates the impact of high temperature and humidity in Italian buffalo milk and that provides correlations with traits of interest for the dairy industry, i.e., milk acidity and coagulation ability. In general, findings show that the effects of elevated THI and heat stress on bulk milk quality in buffalo is less evident than in cattle. These preliminary results intend to open debate on the issue of heat stress in dairy buffaloes that are reared in temperate regions. Further studies should focus on individual milk and performance and should investigate the relationship between high THI and buffalo fertility, behavior, and welfare

    Residential energy expenditures and the relevance of changes in household circumstances

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    This paper analyses the impact that dwelling characteristics and characteristics and behaviours of household members have on per capita energy expenditures. It also analyses whether changes in household socio-economic circumstances translate in changes in energy expenditures. Socio-economic characteristics have a moderate impact, while dwelling characteristics and especially household size have much larger impacts. The largest changes in energy expenditures are due to changes in household size. The recent socio-demographic trends will make it harder to design policies to effectively reduce the carbon footprint of a country, while policies influencing cohabitation and family size may have positive indirect effects

    Polyketone Nanocomposites by Palladium-Catalyzed Ethylene-Carbon Monoxide-(Propene) Co(Ter)polymerization Inside an Unmodified Layered Silicate

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    AbstractComposites from Na-montmorillonite with a content in inorganic material ranging from 3 to 98 wt % were prepared in situ either by copolymerization of ethylene and CO or by terpolymerization of ethylene, propene and CO using a palladium(II) catalyst modified with 1,3-bis(diphenylphosphino)propane. This catalytic system is active in polar media and allowed to produce nanocomposites starting from unmodified Na-montmorillonite in water-methanol solutions. The morphological analysis, performed on samples with less than 40 wt % silicate by XRD and TEM, showed the formation of either intercalated or exfoliated (nanocomposite) structures, depending on the initial amount of the layered silicate in the reactor as well as the presence of propene as comonomer. Improved thermal stability of the hybrid materials, as compared to the corresponding organic polymers, was shown by TGA. A preliminary study of the blending of some polyketone nanocomposites with polyamide (nylon-6) was carried out by melt mixing at high temperature in a Brabender mixer

    Equalizing the Pixel Response of the Imaging Photoelectric Polarimeter On-Board the IXPE Mission

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    The Gas Pixel Detector is a gas detector, sensitive to the polarization of X-rays, currently flying on-board IXPE - the first observatory dedicated to X-ray polarimetry. It detects X-rays and their polarization by imaging the ionization tracks generated by photoelectrons absorbed in the sensitive volume, and then reconstructing the initial direction of the photoelectrons. The primary ionization charge is multiplied and ultimately collected on a finely-pixellated ASIC specifically developed for X-ray polarimetry. The signal of individual pixels is processed independently and gain variations can be substantial, of the order of 20%. Such variations need to be equalized to correctly reconstruct the track shape, and therefore its polarization direction. The method to do such equalization is presented here and is based on the comparison between the mean charge of a pixel with respect to the other pixels for equivalent events. The method is shown to finely equalize the response of the detectors on board IXPE, allowing a better track reconstruction and energy resolution, and can in principle be applied to any imaging detector based on tracks.Comment: Accepted for publication in The Astronomical Journal. 10 pages, 19 figure

    Effect of CMV and Aging on the Differential Expression of CD300a, CD161, T-bet, and Eomes on NK Cell Subsets

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    Natural killer cells are innate lymphoid cells involved in the defence against virus-infected cells and tumour cells. NK cell phenotype and function is affected with age and CMV latent infection. Aging affects the frequency and phenotype of NK cells and CMV infection also contributes to these alterations. Thus, a reduction of CD56bright NK cell subpopulation associated with age and an expansion of memory-like NK cells CD56dimCD57+NKG2C+ probably related to CMV-seropositivity have been described. NK cells express T-bet and Eomes transcription factors that are necessary for the development of NK cells. Here we analyse the effect of age and CMV-seropositivity on the expression of CD300a and CD161 inhibitory receptors and T-bet and Eomes transcription factors in NK cell subsets defined by the expression of CD56 and CD57. CD300a is expressed by the majority of NK cells. CD56bright NK cells express higher levels of CD300a than CD56dim NK cells. An increase in the expression of CD300a was associated with age whereas a decreased expression of CD161 in CD56dim NK cells was associated with CMV-seropositivity. In CD56dim NK cells an increased percentage of CD57+CD300a+ and a reduction in the percentage of CD161+CD300a+ cells were found to be associated with CMV-seropositivity. Regarding T-bet and Eomes transcription factors, CMV-seropositivity was associated with a decrease of T-bethi in CD56dimCD57+ NK cells from young individuals whereas Eomes expression was increased with CMV-seropositivity in both CD56bright and CD56dimCD57+/− (from middle-age and young individuals, respectively) and was decreased with ageing in all NK subsets from the three group of age. In conclusion, CMV infection and age induce significant changes in the expression of CD300a and CD161 in NK cell subsets defined by the expression of CD56 and CD57. T-bet and Eomes are differentially expressed on NK cell subsets and their expression is affected by CMV latent infection and ageing

    The obesity and inflammatory marker haptoglobin attracts monocytes via interaction with chemokine (C-C motif) receptor 2 (CCR2)

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    <p>Abstract</p> <p>Background</p> <p>Obesity is a chronic low inflammatory state. In the obesity condition the white adipose tissue (WAT) is massively infiltrated with monocytes/macrophages, and the nature of the signals recruiting these inflammatory cells has yet to be fully elucidated. Haptoglobin (Hp) is an inflammatory marker and its expression is induced in the WAT of obese subjects. In an effort to elucidate the biological significance of Hp presence in the WAT and of its upregulation in obesity we formulated the hypothesis that Hp may serve as a macrophage chemoattractant.</p> <p>Results</p> <p>We demonstrated by chemotaxis assay that Hp is able to attract chemokine (C-C motif) receptor 2 (CCR2)-transfected pre-B lymphocytes and monocytes in a dose-dependent manner. Moreover, Hp-mediated migration of monocytes is impaired by CCR2-specific inhibition or previous cell exposure to monocyte chemoattractant protein 1 (MCP1) (also known as CCR2 ligand or chemokine (C-C motif) ligand 2 (CCL2)). Downstream effects of Hp/CCR2 interaction were also investigated: flow cytometry proved that monocytes treated with Hp show reduced CCR2 expression on their surface; Hp interaction induces calcium release that is reduced upon pretreatment with CCR2 antagonist; extracellular signal-regulated kinase (ERK)1/2, a signal transducer activated by CCR2, is phosphorylated following Hp treatment and this phosphorylation is reduced when cells are pretreated with a specific CCR2 inhibitor. Consistently, blocking the ERK1/2 pathway with U0126, the selective inhibitor of the ERK upstream mitogen-activated protein (MAP)-ERK kinase (MEK), results in a dramatic reduction (by almost 100%) of the capability of Hp to induce monocyte migration.</p> <p>Conclusions</p> <p>Our data show that Hp is a novel monocyte chemoattractant and that its chemotactic potential is mediated, at least in part. by its interaction with CCR2.</p
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