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1.
For a model class of repellers of non-conformal expanding maps, we obtain sharp lower bounds for the dimension spectra of the Birkhoff averages of a Hölder continuous function. As in the well-studied case of conformal dynamics, the bounds are also expressed here in terms of the thermodynamic formalism. 相似文献
2.
Lucian M. Rusnac Octavian Floarea Radu V. Vladea 《Journal of the American Oil Chemists' Society》1992,69(4):384-386
Continuous hydrogenation of industrially refined soybean oil with Harshaw Ni catalyst was achieved in a slurry column equipped
with Sulzer SMV motionless mixers. The influence of the operating parameters (temperature, pressure, catalyst concentration
and gas velocity) was investigated. The presumption that, in this equipment, the liquid-solid mass transfer limits the rate
of the process is in good agreement with the experimental data. 相似文献
3.
It is now a well-known fact that the phase of electron waves is altered by external magnetic fields via the Aharonov-Bohm effect. This implies that any electron interference effects will be to some degree affected by the presence of such fields. In this study we examine the distortion effects of external (constant and variable) magnetic fields on electron interference and holography. For digital holography, the reconstruction of the object is done via numerical calculations and this leaves the door open for correcting phase distortions in the hologram reconstruction. We design and quantitatively assess such correction schemes, which decidedly depend on our knowledge of the magnetic field values in the holographic recording process. For constant fields of known value we are able to correct for magnetic distortions to a great extent. We find that variable fields are more destructive to the holographic process than constant fields. We define two criteria, related respectively to global and local contrast of the hologram to establish the maximum allowed external field which does not significantly hinder the accuracy of in-line holographic microscopy with electrons. 相似文献
4.
5.
We present a real-time method for sculpting triangular manifold meshes while enabling arbitrary surface deformation with seamless topological changes. Our insight is that the use of quasi-uniform mesh sampling, an interesting option now that very large meshes can be edited and displayed in real-time, provides the right framework for expressing and efficiently processing arbitrary changes of topological genus. The user controls deformation by gesture: he sweeps tools that apply a variety of deformation fields, from smoothing and trimming ones to local inflation and constant volume deformation tools. Meanwhile, the quasi-regular mesh seamlessly splits or locally blends when and where needed, while still following the user-specified deformation. Our method guarantees a closed, self-intersection-free mesh, whatever the user action. We demonstrate the practical usability of the resulting, interactive sculpting system through the sculpture of models that would have been extremely difficult to achieve with both current research methods and state of the art professional software. 相似文献
6.
Oana Baldasici Loredana Balacescu Daniel Cruceriu Andrei Roman Carmen Lisencu Bogdan Fetica Simona Visan Andrei Cismaru Ancuta Jurj Lucian Barbu-Tudoran Valentina Pileczki Laurian Vlase Oana Tudoran Ovidiu Balacescu 《International journal of molecular sciences》2022,23(20)
Neo-adjuvant therapy (NAT) is increasingly used in the clinic for the treatment of breast cancer (BC). Pathological response to NAT has been associated with improved patients’ survival; however, the current techniques employed for assessing the tumor response have significant limitations. Small EVs (sEVs)-encapsulated miRNAs have emerged as promising new biomarkers for diagnosis and prediction. Therefore, our study aims to explore the predictive value of these miRNAs for the pathological response to NAT in BC. By employing bioinformatic tools, we selected a set of miRNAs and evaluated their expression in plasma sEVs and BC biopsies. Twelve miRNAs were identified in sEVs, of which, miR-21-5p, 221-3p, 146a-5p and 26a-5p were significantly associated with the Miller–Payne (MP) pathological response to NAT. Moreover, miR-21-5p, 146a-5p, 26a-5p and miR-24-3p were independent as predictors of MP response to NAT. However, the expression of these miRNAs showed no correlation between sEVs and tissue samples, indicating that the mechanisms of miRNA sorting into sEVs still needs to be elucidated. Functional analysis of miRNA target genes and drug interactions revealed that candidate miRNAs and their targets, can be regulated by different NAT regimens. This evidence supports their role in governing the patients’ therapy response and highlights their potential use as prediction biomarkers. 相似文献
7.
Lucian M. Sprague John H. Arnold 《Journal of the American Oil Chemists' Society》1972,49(8):345A-350A
Estimates of the potential yield from the marine environment have varied between 20–1000 million metric tons because they
were based on poor and incomplete data and differing approaches to trophic level evaluation. The data is improving slightly
and the estimates are beginning to agree within half an order of magnitude. We believe that the yield of marine fisheries
could ultimately be expanded to ca. 400 million metric tons, by utilizing presently known but underutilized resources, by
opening new fisheries in areas like the Indian Ocean and Antarctic and by improving systems of regulating the catch and fishing
effort. In order to meet the maximum potential of the marine environment we will have to harvest at a lower trophic level
in the food chain because most fish in higher trophic levels are being harvested at their maximum sustainable yield. This
increasing harvest of smaller fish, plus the increasing demand for fishmeal for animal feed will cause an increasing proportion
of the fish harvested to be used for reduction to fishmeal and oil.
One of 11 papers presented in the symposium “World Supply of Edible Oils and Proteins,” Atlantic City, October 1971. 相似文献
8.
Preserving mapping consistency under schema changes 总被引:1,自引:0,他引:1
Yannis?VelegrakisEmail author Renée?J.?Miller Lucian?Popa 《The VLDB Journal The International Journal on Very Large Data Bases》2004,13(3):274-293
In dynamic environments like the Web, data sources may change not only their data but also their schemas, their semantics, and their query capabilities. When a mapping is left inconsistent by a schema change, it has to be detected and updated. We present a novel framework and a tool (ToMAS) for automatically adapting (rewriting) mappings as schemas evolve. Our approach considers not only local changes to a schema but also changes that may affect and transform many components of a schema. Our algorithm detects mappings affected by structural or constraint changes and generates all the rewritings that are consistent with the semantics of the changed schemas. Our approach explicitly models mapping choices made by a user and maintains these choices, whenever possible, as the schemas and mappings evolve. When there is more than one candidate rewriting, the algorithm may rank them based on how close they are to the semantics of the existing mappings.Received: 13 January 2004, Accepted: 26 March 2004, Published online: 12 August 2004Edited by: M. Carey 相似文献
9.
We give two optimal linear-time algorithms for computing the Longest Previous Factor (LPF) array corresponding to a string w. For any position i in w, LPF[i] gives the length of the longest factor of w starting at position i that occurs previously in w. Several properties and applications of LPF are investigated. They include computing the Lempel-Ziv factorization of a string and detecting all repetitions (runs) in a string in linear time independently of the integer alphabet size. 相似文献
10.
Bogdan Bucur Gabriel Lucian Radu Constantin Nicolae Toader 《European Food Research and Technology》2008,226(6):1335-1342
A portable bienzymatic analytical system was developed for the chronoamperometric analysis of methanol–ethanol mixtures. The
system consists of two biosensors, one based on alcohol dehydrogenase (ADH) that responds only to the ethanol and the second
one based on alcohol oxidase (AOX) that responds to both methanol and ethanol. The transducers were screen-printed electrodes
(SPEs) modified with mediators: Meldola blue for ADH and Co-phthalocyanine for AOX. The calibration graph of the ADH biosensor
is linear between 0.3 and 8 mmol/L ethanol. The AOX biosensor is able to quantify both analytes in mixtures that contain methanol
between 3 and 70 mmol/L and ethanol ranging from 15 to 110 mmol/L. Interferences due to non-specific oxidations from common
oxidizable compounds like gallic acid and ascorbic acid were smaller in the case of transducer based on Meldola blue. The
analytical system was successfully tested on real samples: non-alcoholised beer (NAB) spiked with ethanol or methanol and
a falsified rose wine (FRW). 相似文献