4,491 research outputs found
Process Intensification of Nicotinic Acid Production via Enzymatic Conversion using Reactive Extraction
Nicotinic acid is widely used in the food, pharmaceutical and biochemical industries. Compared to chemical methods, enzymatic conversion of 3-cyanopyridine is an advantageous alternative for the production of nicotinic acid and nicotinamide. The separation of the product is complicated, owing to its high dilution rate in fermentation broth and high cost. Reactive liquid-liquid extraction by a suitable extractant system has been found to be a promising alternative to the other conventional separation techniques. This paper gives a state-of-the-art review for manufacturing processes (chemical and enzymatic) of nicotinic acid and nicotinamide. It also focuses on the most efficient separation technique, reactive extraction. Reactive extraction has advantages of less consumption of material and energy. It also avoids product inhibition and increases the separation selectivity
Transcriptional Control of Impaired Th1 Responses in Patent Lymphatic Filariasis by T-Box Expressed in T Cells and Suppressor of Cytokine Signaling Genes
T-bet (T-box expressed in T cells) and GATA-3 are transcription factors that play a critical role in the
development of Th1 and Th2 cells, as do genes of the SOCS (suppressor of cytokine signaling) family, albeit
indirectly. Another transcription factor, Foxp3, is a master regulator of natural regulatory T cells (Tregs). To
identify the role of these factors in impaired Th1 responses of patent filarial infection, analysis of cytokine,
SOCS, and transcription factor mRNA expression was performed on purified T cells of filaria-infected
individuals (n � 6) and uninfected controls (n � 6). As expected (and in contrast to cells of uninfected
individuals), there was a significant depression of gamma interferon (IFN-�) and a concomitant increase in
interleukin-4 (IL-4), IL-5, and IL-10 mRNA expression following stimulation with parasite antigen (BmA) but
not with a polyclonal T-cell (anti-CD3) stimulus. T-bet (but not GATA-3) was expressed at significantly lower
levels in cells of filaria-infected individuals in response to BmA compared with those from the uninfected
group, accounting, at least partially, for the diminished IFN-� expression. Second, we found no significant
differences in expression of Foxp3 between the two groups, although induction of Foxp3 expression correlated
with induced expression levels of IL-10, implicating Tregs in the IL-10 expression seen. Finally, parasitespecific
T-cell expression of SOCS-1, SOCS-5, and SOCS-7 was significantly diminished among infected
patients; in contrast, expression of SOCS-3 increased. Our data therefore indicate that the impaired Th1
responses observed in patent lymphatic filariasis are associated with decreased expression of T-bet, SOCS-1,
SOCS-5, and SOCS-7 and increased expression of SOCS-3 in T cells
Modeling charge transport in Swept Charge Devices for X-ray spectroscopy
We present the formulation of an analytical model which simulates charge
transport in Swept Charge Devices (SCDs) to understand the nature of the
spectral redistribution function (SRF). We attempt to construct the
energy-dependent and position dependent SRF by modeling the photon interaction,
charge cloud generation and various loss mechanisms viz., recombination,
partial charge collection and split events. The model will help in optimizing
event selection, maximize event recovery and improve spectral modeling for
Chandrayaan-2 (slated for launch in 2014). A proto-type physical model is
developed and the algorithm along with its results are discussed in this paper.Comment: 9 pages, 7 figures, Proc. SPIE 8453, High Energy, Optical, and
Infrared Detectors for Astronomy
Influence of gas flow rate on liquid distribution in trickle-beds using perforated plates as liquid distributors
Two wire mesh tomography devices and a liquid collector were used to study
the influence of the gas flow rate on liquid distribution when fluids
distribution on top of the reactor is ensured by a perforated plate. In
opposition to most of the studies realized by other authors, conditions in
which the gas has a negative impact in liquid distribution were evidenced.
Indeed, the obtained results show that the influence of gas flow rate depends
on the quality of the initial distribution, as the gas forces the liquid to
"respect" the distribution imposed at the top of the reactor. Finally, a
comparison between the two measuring techniques shows the limitations of the
liquid collector and the improper conclusions to which its use could lead
Finger Ridge Count Correlations Among Four Tribes of Andhra Pradesh, India
The present paper reports the distribution of finger ridge count correlations among
four tribal populations from Andhra Pradesh, India viz., Dulia, Kotia, Manne Dora
and Manzai Mali, and examines the intra and inter population variation. Higher correlations
are recorded in left hands compared to right hands, but they are not significant.
The homologous fingers exhibit a stronger correlation. In all the tribes, the correlations
between right hand fingers are relatively higher among women when compared to men.
Regarding inter population variation Dulia men differ significantly from the men of
Manne Dora and the Manzai Mali tribes, and Kotia women also differ from the women
of the Manne Dora significantly. The average correlation coefficient of the present populations
is similar to other Indian populations reported earlier but lower than African
and European populations
Low Energy Neutrino Physics after SNO and KamLAND
In the recent years important discoveries in the field of low energy neutrino
physics (E in the MeV range) have been achieved. Results of the
solar neutrino experiment SNO show clearly flavor transitions from to
. In addition, the long standing solar neutrino problem is
basically solved. With KamLAND, an experiment measuring neutrinos emitted from
nuclear reactors at large distances, evidence for neutrino oscillations has
been found. The values for the oscillation parameters, amplitude and phase,
have been restricted. In this paper the potential of future projects in low
energy neutrino physics is discussed. This encompasses future solar and reactor
experiments as well as the direct search for neutrino masses. Finally the
potential of a large liquid scintillator detector in an underground laboratory
for supernova neutrino detection, solar neutrino detection, and the search for
proton decay is discussed.Comment: Invited brief review, World Scientific Publishing Compan
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