68 research outputs found
Patterns and localized structures in bistable semiconductor resonators
We report experiments on spatial switching dynamics and steady state
structures of passive nonlinear semiconductor resonators of large Fresnel
number. Extended patterns and switching front dynamics are observed and
investigated. Evidence of localization of structures is given.Comment: 5 pages with 9 figure
Production of fructooligosaccharides and b-fructofuranosidase by batch and repeated batch fermentation with immobilized cells of Penicillium expansum
The production of fructooligosaccharides
(FOS) and b-fructofuranosidase (FFase) by immobilized
cells of Penicillium expansum was evaluated. In an initial
stage, different low-cost materials including synthetic fiber,
polyurethane foam, stainless steel sponge, loofah sponge,
and cork oak were tested as carrier for the fungus immobilization.
Additionally, the influence of the inoculum age
(1 or 3 weeks) on cells immobilization, FOS and FFase
production was also verified. Synthetic fiber and polyurethane
foam were the best materials for P. expansum
immobilization (2.21 and 1.98 g/g carrier, respectively)
and FOS production (120.3 and 104.8 g/l), and gave also
high results of FFase activity (23.01 and 32.42 U/ml).
Then, the production of FOS and FFase by repeated batch
fermentation with P. expansum immobilized on synthetic
fiber was studied, aiming to improve the batch fermentation
results. The results obtained in this stage were very
promising with FOS yields of 87, 72, and 44 %, in the 3
initial cycles (60 h), respectively; the FFase activity was
constant throughout the process (6 cycles, 96 h). Repeated
batch fermentation with immobilized cells of P. expansum
was found as being a technology with great potential for
FOS and FFase production on industrial scaleThe financial support from FCT, the Portuguese Foundation for Science and Technology (research grant SFRH/BPD/38212/2007) is gratefully acknowledged
Clinical significance of circulating anti-p53 antibodies in European patients with hepatocellular carcinoma
p53 alterations are considered to be predictive of poor prognosis in hepatocellular carcinoma (HCC) and may induce a humoral response. Anti-p53 serum antibodies were assessed by enzyme-linked immunosorbent assay (ELISA) using purified recombinant human p53 on 130 European HCC patients before treatment and during the clinical course of the disease. p53 immunohistochemistry was performed on tumours from the 52 patients who underwent surgery, and DNA sequencing analysis was initiated when circulating anti-p53 antibodies were detected. Nine (7%) HCC patients had anti-p53 serum antibodies before treatment. During a mean period of 30 months of follow-up, all the negative patients remained negative, even when recurrence was observed. Of the nine positive patients, eight were still positive 12–30 months after surgery. The presence of anti-p53 serum antibodies was correlated neither with mutation of the p53 gene nor the serum alpha-fetoprotein levels and clinicopathological characterics of the tumours. However, a greater incidence of vascular invasion and accumulation of p53 protein were observed in the tumours of these patients (P < 0.03 and P < 0.01 respectively) as well as a better survival rate without recurrence (P = 0.05). In conclusion, as was recently shown in pancreatic cancer, anti-p53 serum antibodies may constitute a marker of relative ‘good prognosis’ in a subgroup of patients exhibiting one or several markers traditionally thought to be of bad prognosis. © 1999 Cancer Research Campaig
The "Statinth" wonder of the world: a panacea for all illnesses or a bubble about to burst
After the introduction of statins in the market as effective lipid lowering agents, they were shown to have effects other than lipid lowering. These actions were collectively referred to as 'pleiotropic actions of statins.' Pleiotropism of statins formed the basis for evaluating statins for several indications other than lipid lowering. Evidence both in favour and against is available for several of these indications. The current review attempts to critically summarise the available data for each of these indications
Microseismicity within a karstified rock mass due to cracks and collapses as a tool for risk management
Analyse des sous produits de la chloration et des précurseurs de trihalométhanes
Différentes techniques analytiques des sous-produits de la chloration sont testées durant cette étude : la technique "Head space" permet une analyse corrécte des trihalométhanes (THM), mais pour effectuer l'analyse des halopropanones, haloacetonitriles, chloropicrine et de l'hydrate de chloral l'extraction liquide/liquide au ter-butylmethylether (TBME) est nécessaire. Une évaluation des précurseurs de THM est aussi effectuée en analysant le potentiel de formation des THM à pH 7,5, à l'obscurité et à 21°C. Les conditions optimates de temps de contact et de taux de chloration de la formation des THM sont définies.
A partir de ces différents protocoles expérimentaux le suivi d'une eau traitée et de sa ressource est effectué. Les THM sont les sous-produits de la chloration prépondérants dans l'eau potable, mais l'hydrate de chloral, le dichloroacétonitrile, le chlorobromoacétonitrile et le trichloropropanone sont aussi detectés à des teneurs élevées. La mesure des précurseurs de THM de l 'eau brute nous renseigne sur la qualité de l 'eau traitée en ce qui concerne sa teneur en THM et aussi en précurseurs de THM résiduels
Reorganization of Thalamic Intrinsic Connectivity Following Anterior Temporal Lobectomy
The thalamus has played a crucial role in determining surgical outcome following anterior temporal lobectomy (ATL) in temporal lobe epilepsy (TLE) (He, et al., 2017). Before successfully quantifying the impact of the thalamus on ATL outcomes, this structure’s own intrinsic connectivity must be understood. Accordingly, we characterize thalamic intrinsic connectivity through resting-state fMRI (rsfMRI) longitudinally, exploring its change pre- to post-surgery.https://jdc.jefferson.edu/neurosurgeryposters/1010/thumbnail.jp
Fossil black smoker yields oxygen isotopic composition of Neoproterozoic seawater
Uncertainty regarding the evolution of the oxygen isotopic composition of seawater casts doubt on past temperature reconstructions. Here, the authors present a new, precise δ18O value for the Neoproterozoic, and propose that ocean temperatures on the eve of the Sturtian glaciation were 15–30 °C warmer than present
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