5,171 research outputs found
Demonstration of early functional compromise of bone marrow derived hematopoietic progenitor cells during bovine neonatal pancytopenia through in vitro culture of bone marrow biopsies
<p>Abstract</p> <p>Background</p> <p>Bovine neonatal pancytopenia (BNP) is a syndrome characterised by thrombocytopenia associated with marked bone marrow destruction in calves, widely reported since 2007 in several European countries and since 2011 in New Zealand. The disease is epidemiologically associated with the use of an inactivated bovine virus diarrhoea (BVD) vaccine and is currently considered to be caused by absorption of colostral antibody produced by some vaccinated cows (“BNP dams”). Alloantibodies capable of binding to the leukocyte surface have been detected in BNP dams and antibodies recognising bovine MHC class I and β-2-microglobulin have been detected in vaccinated cattle. In this study, calves were challenged with pooled colostrum collected from BNP dams or from non-BNP dams and their bone marrow hematopoietic progenitor cells (HPC) cultured <it>in vitro</it> from sternal biopsies taken at 24 hours and 6 days post-challenge.</p> <p>Results</p> <p>Clonogenic assay demonstrated that CFU-GEMM (colony forming unit-granulocyte/erythroid/macrophage/megakaryocyte; pluripotential progenitor cell) colony development was compromised from HPCs harvested as early as 24 hour post-challenge. By 6 days post challenge, HPCs harvested from challenged calves failed to develop CFU-E (erythroid) colonies and the development of both CFU-GEMM and CFU-GM (granulocyte/macrophage) was markedly reduced.</p> <p>Conclusion</p> <p>This study suggests that the bone marrow pathology and clinical signs associated with BNP are related to an insult which compromises the pluripotential progenitor cell within the first 24 hours of life but that this does not initially include all cell types.</p
Fine structural analyses of pancreatic acinar cell nuclei from mice fed on genetically modified soybean
We carried out ultrastructural morphometrical and immunocytochemical analyses on pancreatic acinar cell nuclei from mice fed on genetically modified (GM) soybean, in order to investigate possible structural and molecular modifications of nucleoplasmic and nucleolar constituents.We found a significant lowering of nucleoplasmic and nucleolar splicing factors as well as a perichromatin granule accumulation in GM-fed mice, suggestive of reduced post-transcriptional hnRNA processing and/or nuclear export. This is in accordance to already described zymogen synthesis and processing modifications in the same animals
Quark nuggets search using 2350 Kg gravitational waves aluminum bar detectors
The gravitational wave resonant detectors can be used as detectors of quark
nuggets, like nuclearites (nuclear matter with a strange quark). This search
has been carried out using data from two 2350 Kg, 2 K cooled, aluminum bar
detectors: NAUTILUS, located in Frascati (Italy), and EXPLORER, that was
located in CERN Geneva (CH). Both antennas are equipped with cosmic ray shower
detectors: signals in the bar due to showers are continuously detected and used
to characterize the antenna performances. The bar excitation mechanism is based
on the so called thermo-acoustic effect, studied on dedicated experiments that
use particle beams. This mechanism predicts that vibrations of bars are induced
by the heat deposited in the bar from the particle. The geometrical acceptance
of the bar detectors is 19.5 sr, that is smaller than that of other
detectors used for similar searches. However, the detection mechanism is
completely different and is more straightforward than in other detectors. We
will show the results of ten years of data from NAUTILUS (2003-2012) and 7
years from EXPLORER (2003-2009). The experimental limits we obtain are of
interest because, for nuclearites of mass less than grams, we find a
flux smaller than that one predicted considering nuclearites as dark matter
candidates.Comment: presented to the 33rd International Cosmic Ray Conference Rio de
Janeiro 201
Erythrocyte morphology automated analysis: proposal for a new prediction tool of essential hypertension diagnosis
Erythrocyte morphology has already been studied in essential hypertension (EH) and cell membrane alterations have been observed. Relationships among red cell rheological, biochemical, and morphological properties still appear complex and are not clearly understood
Analysis of 3 years of data from the gravitational wave detectors EXPLORER and NAUTILUS
We performed a search for short gravitational wave bursts using about 3 years
of data of the resonant bar detectors Nautilus and Explorer. Two types of
analysis were performed: a search for coincidences with a low background of
accidentals (0.1 over the entire period), and the calculation of upper limits
on the rate of gravitational wave bursts. Here we give a detailed account of
the methodology and we report the results: a null search for coincident events
and an upper limit that improves over all previous limits from resonant
antennas, and is competitive, in the range h_rss ~1E-19, with limits from
interferometric detectors. Some new methodological features are introduced that
have proven successful in the upper limits evaluation.Comment: 12 pages, 12 figure
Dark Matter searches using gravitational wave bar detectors: quark nuggets and newtorites
Many experiments have searched for supersymmetric WIMP dark matter, with null
results. This may suggest to look for more exotic possibilities, for example
compact ultra-dense quark nuggets, widely discussed in literature with several
different names. Nuclearites are an example of candidate compact objects with
atomic size cross section. After a short discussion on nuclearites, the result
of a nuclearite search with the gravitational wave bar detectors Nautilus and
Explorer is reported. The geometrical acceptance of the bar detectors is 19.5
sr, that is smaller than that of other detectors used for similar
searches. However, the detection mechanism is completely different and is more
straightforward than in other detectors. The experimental limits we obtain are
of interest because, for nuclearites of mass less than g, we find a
flux smaller than that one predicted considering nuclearites as dark matter
candidates. Particles with gravitational only interactions (newtorites) are
another example. In this case the sensitivity is quite poor and a short
discussion is reported on possible improvements.Comment: published on Astroparticle Physics Sept 25th 2016 replaced fig 1
Effect of cosmic rays on the resonant gravitational wave detector NAUTILUS at temperature T=1.5 K
The interaction between cosmic rays and the gravitational wave bar detector
NAUTILUS is experimentally studied with the aluminum bar at temperature of
T=1.5 K. The results are compared with those obtained in the previous runs when
the bar was at T=0.14 K. The results of the run at T = 1.5 K are in agreement
with the thermo-acoustic model; no large signals at unexpected rate are
noticed, unlike the data taken in the run at T = 0.14 K. The observations
suggest a larger efficiency in the mechanism of conversion of the particle
energy into vibrational mode energy when the aluminum bar is in the
superconductive status.Comment: 7 pages, 3 figures, 2 tables. Accepted by Physics Letters
Study of the coincidences between the gravitational wave detectors EXPLORER and NAUTILUS in 2001
We report the result from a search for bursts of gravitational waves using
data collected by the cryogenic resonant detectors EXPLORER and NAUTILUS during
the year 2001, for a total measuring time of 90 days. With these data we
repeated the coincidence search performed on the 1998 data (which showed a
small coincidence excess) applying data analysis algorithms based on known
physical characteristics of the detectors. With the 2001 data a new interesting
coincidence excess is found when the detectors are favorably oriented with
respect to the Galactic Disk
State-of-the-art in product service-systems
A Product Service-System (PSS) is an integrated combination of products and services.
This western concept embraces a service-led competitive strategy, environmental sustainability,
and the basis to differentiate from competitors who simply offer lower priced products. This
paper aims to report the state-of-the-art of PSS research by presenting a clinical review of
literature currently available on this topic. The literature is classified and the major outcomes
of each study are addressed and analysed. On this basis, this paper defines the PSS concept,
reports on its origin and features, gives examples of applications along with potential benefits
and barriers to adoption, summarises available tools and methodologies, and identifies future
research challenges
STRUCTURAL PROPERTIES AND FUNCTIONAL TAILORING OF REFINED OR UNREFINED PLANT-BASED MATERIALS OBTAINED BY EXTRACTION OR BIO-TRANSFORMATION OF AGRO-FOOD WASTES
L\u2019impiego delle risorse in maniera efficiente \ue8 una tematica di interesse globale, sia da un punto di vista ambientale che economico. La produzione di grandi quantit\ue0 di residui agro-alimentari \ue8 una delle principali cause di inefficienza a livello di produzione industriale. Questi materiali hanno ancora un elevato contenuto di materiale organico, ricco in composti naturali preziosi e peculiari strutture che, una volta identificati, possono essere estratti e valorizzati per via fisica, chimica o biotecnologica. Per queste ragioni, negli ultimi anni si osserva un crescente interesse sia scientifico che industriale per il recupero e la valorizzazione di materiali di scarto.
In questo contesto, questo progetto di dottorato si propone di investigare le potenzialit\ue0 di ingredienti derivati da residui agro-alimentari per la formulazione alimentare. La caratterizzazione strutturale e funzionale delle matrici considerate ha seguito un approccio tipico della scienza dei materiali, basato sull\u2019analisi quantitativa mediante modelli matematici per promuovere e controllare specifici fenomeni e modificazioni in grado di migliorare le propriet\ue0 funzionali del sistema formulato.
Nella presente tesi di dottorato sono stati considerati quattro diversi materiali. La cellulosa nano cristallina \ue8 stata caratterizzata da un punto di vista reo-ottico per meglio comprendere quale sia relazione esistente tra l\u2019organizzazione nematica e lo stato cineticamente arrestato. Gli estratti di parete vegetale (CWM) sono stati studiati nell\u2019ottica di un loro impiego come sistemi per il trasporto di composti bioattivi, agendo soprattutto sull\u2019organizzazione della matrice polimerica di parete con lo scopo di poter meglio controllare il rilascio dei composti di interesse. Le frazioni di farina di semi di canapa sono state valutate in termini di capacit\ue0 texturizzante e strutturante. La cellulosa batterica si \ue8 dimostrata invece un eccellente supporto per la ritenzione di molecole volatili.The efficient exploitation of resources is a topic of concern worldwide, from both an environmental and economic point of view. The production of large amounts of agro-food residues is one of the main causes for the inefficiency of industrial-scale food production. These are materials of high organic load, where valuable natural compounds and structures can be identified and extracted in order to valorize wastes via physical, chemical or biotechnological processing. For this reason, an intensive investigation for the recovery of materials with improved functional properties has been carried out in the last years.
In this framework, this PhD doctoral project aimed to explore the potentiality of residue-derived ingredients for the food formulation. Structural and functional characterization of the proposed matrices was performed with a material science point of view, based on the quantitative analysis through mathematical models to promote and control adequate changes which can improve some functional properties in the food.
In the present thesis, four different materials were considered. Cellulose nanocrystals were characterized with a rheo-optical approach in order to provide an insight into the relationship between nematic ordering and kinetic arrest. Cell wall materials were studied as carrier of bioactive compounds, with the purpose of tuning the wall matrix organization to obtain a sustained release. Hemp seed meal fractions were evaluated because of their texturing and structuring abilities. The use of bacterial cellulose as support for the retain of volatile molecules was also investigated, along with its thickening ability
- …
