273 research outputs found
Evaluation of ultraviolet‐C and spray‐drying processes as two independent inactivation steps on enterotoxigenic Escherichia coli K88 and K99 strains inoculated in fresh unconcentrated porcine plasma
The objectives of this study were to assess the effectiveness of an ultraviolet (UV‐C, 254 nm) irradiation system and the spray‐drying method as two independent safety steps on inactivation of Escherichia coli K88 and K99 spiked in porcine plasma at 6·46 ± 0·04 log10 ml−1 and 6·78 ± 0·67 log10 ml−1 respectively for UV‐C method, and at 7·31 ± 0·39 log10 ml−1 and 7·66 ± 0·11 log10 ml−1, respectively for the spray‐drying method. The UV‐C method was performed at different UV light doses (from 750 to 9000 J l−1) using a pilot plant UV‐C device working under turbulent flow. Spray‐drying treatment was done at inlet temperature 220 ± 1°C and two different outlet temperatures, 80 ± 1°C or 70 ± 1°C. Results indicated that UV‐C treatment induced a 4 log10 viability reduction for both E. coli at 3000 J l−1. Full inactivation of both E. coli strains was achieved in all spray‐dried samples dehydrated at both outlet temperatures. The special UV‐C system design for turbid liquid porcine plasma is a novel treatment that can provide an additional redundant biosafety feature that can be incorporated into the manufacturing process for spray‐dried animal plasma.info:eu-repo/semantics/publishedVersio
Traffic Equations and Granular Convection
We investigate both numerically and analytically the convective instability
of granular materials by two dimensional traffic equations. In the absence of
vibrations the traffic equations assume two distinctive classes of fixed bed
solutions with either a spatially uniform or nonuniform density profile. The
former one exists only when the function V(\rho) that monitors the relaxation
of grains assumes a cut off at the closed packed density, \rho_c, with
V(\rho_c)=0, while the latter one exists for any form of V. Since there is
little difference between the uniform and nonuniform solution deep inside the
bed, the convective instability of the bulk may be studied by focusing on the
stability of the uniform solution. In the presence of vibrations, we find that
the uniform solution bifurcates into a bouncing solution, which then undergoes
a supercritical bifurcation to the convective instability. We determine the
onset of convection as a function of control parameters and confirm this
picture by solving the traffic equations numerically, which reveals bouncing
solutions, two convective rolls, and four convective rolls. Further, convective
patterns change as the aspect ratio changes: in a vertically long container,
the rolls move toward the surface, and in a horizontally long container, the
rolls move toward the walls. We compare these results with those reported
previously with a different continuum model by Hayakawa, Yue and Hong[Phys.
Rev. Lett. 75,2328, 1995]. Finally, we also present a derivation of the traffic
equations from Enskoq equation.Comment: 34 pages, 10 figure
Gambling: Electronic friends or a threat to one's health and personal development?
Gambling has become quite common in Sweden. The Swedish National Institute of Public Health (2010) has reported that about 70% of the Swedish population has gambled at least once during the last 12 months. Half of the population had gambled with money by 18 years of age and about 11% had gambled for the first time when they were 12-years-old or younger. In the report from the Swedish National Institute of Public Health, gambling problems are related to health problems and risky alcohol consumption. The highest problem rate is found among men aged 18 to 24; almost 1 in 10 had some gambling problems. The share of problem gamblers is found to be twice as high among the under-age gamblers as it is among the population as a whole. Young people gamble less but develop gambling problems to a larger extent than adult gamblers. In this article young people's gambling and their gambling careers are analysed as a natural part of their internalisation of other adult habits
Three SRA-Domain Methylcytosine-Binding Proteins Cooperate to Maintain Global CpG Methylation and Epigenetic Silencing in Arabidopsis
Methylcytosine-binding proteins decipher the epigenetic information encoded by DNA methylation and provide a link between DNA methylation, modification of chromatin structure, and gene silencing. VARIANT IN METHYLATION 1 (VIM1) encodes an SRA (SET- and RING-associated) domain methylcytosine-binding protein in Arabidopsis thaliana, and loss of VIM1 function causes centromere DNA hypomethylation and centromeric heterochromatin decondensation in interphase. In the Arabidopsis genome, there are five VIM genes that share very high sequence similarity and encode proteins containing a PHD domain, two RING domains, and an SRA domain. To gain further insight into the function and potential redundancy among the VIM proteins, we investigated strains combining different vim mutations and transgenic vim knock-down lines that down-regulate multiple VIM family genes. The vim1 vim3 double mutant and the transgenic vim knock-down lines showed decreased DNA methylation primarily at CpG sites in genic regions, as well as repeated sequences in heterochromatic regions. In addition, transcriptional silencing was released in these plants at most heterochromatin regions examined. Interestingly, the vim1 vim3 mutant and vim knock-down lines gained ectopic CpHpH methylation in the 5S rRNA genes against a background of CpG hypomethylation. The vim1 vim2 vim3 triple mutant displayed abnormal morphological phenotypes including late flowering, which is associated with DNA hypomethylation of the 5′ region of FWA and release of FWA gene silencing. Our findings demonstrate that VIM1, VIM2, and VIM3 have overlapping functions in maintenance of global CpG methylation and epigenetic transcriptional silencing
Technology Adoption by Elderly People – An Empirical Analysis of Adopters and Non-Adopters of Social Networking Sites
This research paper analyzes the impact of attitudinal, control and normative beliefs on the intention to use social network sites (SNS) by people older than 50. Using the Model of Adoption of Technology in Households (MATH) and the data of 115 social network site adopters and 53 non-adopters it can be shown that the intention of adopters and non-adopters has been influenced by different reasons. Perceived Ease of Use and Normative Beliefs have only a significant impact for adopters. Moreover, this research paper unfolds Fear of Technology as a strong influence factor for non-adopters in regard not to use SNS in their daily routine. The paper concludes with a discussion of an age-sensitive design of SNS in order to address the digital divide
Metal A and Metal B Sites of Nuclear RNA Polymerases Pol IV and Pol V Are Required for siRNA-Dependent DNA Methylation and Gene Silencing
Plants are unique among eukaryotes in having five multi-subunit nuclear RNA polymerases: the ubiquitous RNA polymerases I, II and III plus two plant-specific activities, nuclear RNA polymerases IV and V (previously known as Polymerases IVa and IVb). Pol IV and Pol V are not required for viability but play non-redundant roles in small interfering RNA (siRNA)-mediated pathways, including a pathway that silences retrotransposons and endogenous repeats via siRNA-directed DNA methylation. RNA polymerase activity has not been demonstrated for Polymerases IV or V in vitro, making it unclear whether they are catalytically active enzymes. Their largest and second-largest subunit sequences have diverged considerably from Pol I, II and III in the vicinity of the catalytic center, yet retain the invariant Metal A and Metal B amino acid motifs that bind magnesium ions essential for RNA polymerization. By using site-directed mutagenesis in conjunction with in vivo functional assays, we show that the Metal A and Metal B motifs of Polymerases IV and V are essential for siRNA production, siRNA-directed DNA methylation, retrotransposon silencing, and the punctate nuclear localization patterns typical of both polymerases. Collectively, these data show that the minimal core sequences of polymerase active sites, the Metal A and B sites, are essential for Pol IV and Pol V biological functions, implying that both are catalytically active
Carbon fluxes resulting from land-use changes in the Tamaulipan thornscrub of northeastern Mexico
Information on carbon stock and flux resulting from land-use changes in subtropical, semi-arid ecosystems are important to understand global carbon flux, yet little data is available. In the Tamaulipan thornscrub forests of northeastern Mexico, biomass components of standing vegetation were estimated from 56 quadrats (200 m2 each). Regional land-use changes and present forest cover, as well as estimates of soil organic carbon from chronosequences, were used to predict carbon stocks and fluxes in this ecosystem
Evaluating the effectiveness of agricultural adaptation to climate change in preindustrial society
The effectiveness of agricultural adaptation determines the vulnerability of this sector to climate change, particularly during the preindustrial era. However, this effectiveness has rarely been quantitatively evaluated, specifically at a large spatial and long-term scale. The present study covers this case of preindustrial society in AD 1500–1800. Given the absence of technological innovations in this time frame, agricultural production was chiefly augmented by cultivating more land (land input) and increasing labor input per land unit (labor input). Accordingly, these two methods are quantitatively examined. Statistical results show that within the study scale, land input is a more effective approach of mitigating climatic impact than labor input. Nonetheless, these observations collectively improve Boserup's theory from the perspective of a large spatial and long-term scale.postprin
CD(8+ )T lymphocytes in lung tissue from patients with idiopathic pulmonary fibrosis
BACKGROUND: Several studies have implicated a role of inflammation in the pathogenesis of lung damage in idiopathic pulmonary fibrosis (IPF). Parenchymal lung damage leads to defects in mechanics and gas exchange and clinically manifests with exertional dyspnea. Investigations of inflammatory cells in IPF have shown that eosinophils, neutrophils and CD(8+ )TLs may be associated with worse prognosis. We wished to investigate by quantitative immunohistochemistry infiltrating macrophages, neutrophils and T lymphocytes (TLs) subpopulations (CD(3+), CD(4+ )and CD(8+)) in lung tissue of patients with IPF and their correlation with lung function indices and grade of dyspnoea. METHODS: Surgical biopsies of 12 patients with IPF were immunohistochemically stained with mouse monoclonal antibodies (anti-CD(68 )for macrophages, anti-elastase for neutrophils, and anti-CD(3), anti-CD(4), anti-CD(8 )for CD(3+)TLs, CD(4+)TLs, and CD(8+)TLs respectively). The number of positively stained cells was determined by observer-interactive computerized image analysis (SAMBA microscopic image processor). Cell numbers were expressed in percentage of immunopositive nuclear surface in relation to the total nuclear surface of infiltrative cells within the tissue (labeling Index). Correlations were performed between cell numbers and physiological indices [FEV(1), FVC, TLC, DLCO, PaO(2), PaCO(2 )and P(A-a)O(2))] as well as dyspnoea scores assessed by the Medical Research Council (MRC) scale. RESULTS: Elastase positive cells accounted for the 7.04% ± 1.1 of total cells, CD(68+ )cells for the 16.6% ± 2, CD(3+ )TLs for the 28.8% ± 7, CD(4+ )TLs for the 14.5 ± 4 and CD(8+ )TLs for the 13.8 ± 4. CD(8+)TLs correlated inversely with FVC % predicted (r(s )= -0.67, p = 0.01), TLC % predicted (r(s )= -0.68, p = 0.01), DLCO % predicted (r(s )= -0.61, p = 0.04), and PaO(2 )(r(s )= -0.60, p = 0.04). Positive correlations were found between CD(8+)TLs and P(A-a)O(2 )(r(s )= 0.65, p = 0.02) and CD(8+)TLs and MRC score (r(s )= 0.63, p = 0.02). Additionally, CD(68+ )cells presented negative correlations with both FVC % predicted (r(s )= -0.80, p = 0.002) and FEV(1 )% predicted (r(s )= -0.68, p = 0.01). CONCLUSION: In UIP/IPF tissue infiltrating mononuclear cells and especially CD(8+ )TLs are associated with the grade of dyspnoea and functional parameters of disease severity implicating that they might play a role in its pathogenesis
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