347 research outputs found
Effect of operating parameters and cleaning on the performance of ceramic membranes treating partially clarified sugar cane juice
The performance of ceramic membranes with pore sizes of 0.05 and 0.10 mm in purifying limed and partially clarified sugar cane juice was investigated under different operating conditions. From various operating conditions and strategies, switching off the permeate for 5 seconds for every 5 minutes (S5sT5 m) by an automated control valve provided higher flux. From the three pH experiments conducted on the 0.05 mm membrane, the best performance was observed at a pH of 7.5. Amongst the four fouling models tested, the cake filtration model fitted the performance of both membranes with higher accuracy at a transmembrane pressure of 0.5 bar. Filtering the cane juice through the membrane reduced the turbidity by 99.7%, color by 15%, and the starch concentration by 80% as well as increased the purity by 1.4%. The effective cleaning chemical composition from experimental results showed that 1% NaOH and 3000 ppm NaOCl solution performed the best but only for the experiments that were treating limed and partially clarified juice at pH 7.5.<br /
General one-loop formulas for decay
Radiative corrections to the are evaluated in the
one-loop approximation. The unitary gauge gauge is used. The analytic result is
expressed in terms of the Passarino-Veltman functions. The calculations are
applicable for the Standard Model as well for a wide class of its gauge
extensions. In particular, the decay width of a charged Higgs boson can be derived. The consistence of our formulas and
several specific earlier results is shown.Comment: 33 pages, 3 figures, a new section (V) and references were improved
in the published versio
Momentum Analyticity and Finiteness of the 1-Loop Superstring Amplitude
The Type II Superstring amplitude to 1-loop order is given by an integral of
-functions over the moduli space of tori, which diverges for real
momenta. We construct the analytic continuation which renders this amplitude
well defined and finite, and we find the expected poles and cuts in the complex
momentum plane.Comment: 10pp, /UCLA/93/TEP/
Simple matrix models for random Bergman metrics
Recently, the authors have proposed a new approach to the theory of random
metrics, making an explicit link between probability measures on the space of
metrics on a Kahler manifold and random matrix models. We consider simple
examples of such models and compute the one and two-point functions of the
metric. These geometric correlation functions correspond to new interesting
types of matrix model correlators. We study a large class of examples and
provide in particular a detailed study of the Wishart model.Comment: 23 pages, IOP Latex style, diastatic function Eq. (22) and contact
terms in Eqs. (76, 95) corrected, typos fixed. Accepted to JSTA
Second cohomology for finite groups of Lie type
Let be a simple, simply-connected algebraic group defined over
. Given a power of , let
be the subgroup of -rational points. Let be the
simple rational -module of highest weight . In this paper we
establish sufficient criteria for the restriction map in second cohomology
to be an
isomorphism. In particular, the restriction map is an isomorphism under very
mild conditions on and provided is less than or equal to a
fundamental dominant weight. Even when the restriction map is not an
isomorphism, we are often able to describe in
terms of rational cohomology for . We apply our techniques to compute
in a wide range of cases, and obtain new
examples of nonzero second cohomology for finite groups of Lie type.Comment: 29 pages, GAP code included as an ancillary file. Rewritten to
include the adjoint representation in types An, B2, and Cn. Corrections made
to Theorem 3.1.3 and subsequent dependent results in Sections 3-4. Additional
minor corrections and improvements also implemente
On the Quantum Inverse Problem for the Closed Toda Chain
We reconstruct the canonical operators of the quantum closed Toda
chain in terms of Sklyanin's separated variables.Comment: 16 page
Bergman kernel and complex singularity exponent
We give a precise estimate of the Bergman kernel for the model domain defined
by where
is a holomorphic map from to ,
in terms of the complex singularity exponent of .Comment: to appear in Science in China, a special issue dedicated to Professor
Zhong Tongde's 80th birthda
Predicting HIV Pre-exposure Prophylaxis Efficacy for Women using a Preclinical Pharmacokinetic-Pharmacodynamic In Vivo Model
The efficacy of HIV pre-exposure prophylaxis (PrEP) relies on adherence and may also depend on the route of HIV acquisition. Clinical studies of systemic tenofovir disoproxil fumarate (TDF) PrEP revealed reduced efficacy in women compared to men with similar degrees of adherence. To select the most effective PrEP strategies, preclinical studies are critically needed to establish correlations between drug concentrations (pharmacokinetics [PK]) and protective efficacy (pharmacodynamics [PD]). We utilized an in vivo preclinical model to perform a PK-PD analysis of systemic TDF PrEP for vaginal HIV acquisition. TDF PrEP prevented vaginal HIV acquisition in a dose-dependent manner. PK-PD modeling of tenofovir (TFV) in plasma, female reproductive tract tissue, cervicovaginal lavage fluid and its intracellular metabolite (TFV diphosphate) revealed that TDF PrEP efficacy was best described by plasma TFV levels. When administered at 50 mg/kg, TDF achieved plasma TFV concentrations (370 ng/ml) that closely mimicked those observed in humans and demonstrated the same risk reduction (70%) previously attained in women with high adherence. This PK-PD model mimics the human condition and can be applied to other PrEP approaches and routes of HIV acquisition, accelerating clinical implementation of the most efficacious PrEP strategies
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