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41.
This paper presents a colour classification of coastal waters from features of spectral reflectance. Experimental data were collected in coastal waters of the Ebro river mouth area during two periods of non-bloom conditions and low suspended load. Examination of the reflectance spectra reveals a few significant shapes corresponding to different apparent colours and specific values of hydrological parameters. A colour classification is proposed. An empirical method and a semi-analytical method are presented in order to retrieve suspended particulate matter concentration, namely SPM, chlorophyll a concentration, chl, sediment refractive index, mr , and absorption coefficient of yellow substance at 440 nm, a y (440). The first method is a direct application of the colour classification. It is based on correlations found for each water type between spectral features of the first derivative of reflectance and SPM, chl, mr , ay (440) values. A second method uses the inversion of a three component reflectance model. Measured reflectance spectra and typical values of mr , deduced from the colour classification, are assimilated in the model. As a result, it appears that estimates of SPM and chl are more accurate by calculating chl from the correlation technique and SPM along with ay (440) from inversion of the reflectance model.  相似文献   
42.
43.
More than 40 % of the world's population is at risk of being infected with malaria. Most malaria cases occur in the countries of sub‐Saharan Africa, Central and South America, and Asia. Resistance to standard therapy, including artemisinin combinations, is increasing. There is an urgent need for novel antimalarials with new mechanisms of action. In a phenotypic screen, we identified a series of phenylalanine‐based compounds that exhibit antimalarial activity via a new and yet unknown mechanism of action. Our optimization efforts culminated in the selection of ACT‐451840 [(S,E)‐N‐(4‐(4‐acetylpiperazin‐1‐yl)benzyl)‐3‐(4‐(tert‐butyl)phenyl)‐N‐(1‐(4‐(4‐cyanobenzyl)piperazin‐1‐yl)‐1‐oxo‐3‐phenylpropan‐2‐yl)acrylamide] for clinical development. Herein we describe our optimization efforts from the screening hit to the potential drug candidate with respect to antiparasitic activity, drug metabolism and pharmacokinetics (DMPK) properties, and in vivo pharmacological efficacy.  相似文献   
44.
Retro‐1 is a small molecule that displays two important biological activities: First, it blocks the actions of certain toxins by altering their intracellular trafficking. Second, it enhances the activity of oligonucleotides by releasing them from entrapment in endosomes. This raises the question of whether the two actions involve the same cellular target. Herein we report the effects of several Retro‐1 analogues on both toxins and oligonucleotides. We found analogues that affect toxins but not oligonucleotides and vice‐versa, while Retro‐1 is the only compound that affects both. This indicates that the molecular target(s) involved in the two processes are distinct.  相似文献   
45.
As the scale of computing platforms becomes increasingly extreme, the requirements for application fault tolerance are increasing as well. Techniques to address this problem by improving the resilience of algorithms have been developed, but they currently receive no support from the programming model, and without such support, they are bound to fail. This paper discusses the failure-free overhead and recovery impact of the user-level failure mitigation proposal presented in the MPI Forum. Experiments demonstrate that fault-aware MPI has little or no impact on performance for a range of applications, and produces satisfactory recovery times when there are failures.  相似文献   
46.
The principle of the equivalence of gravitational and inertial mass is one of the cornerstones of general relativity. Considerable efforts have been made and are still being made to verify its validity. A quantum-mechanical formulation of gravity allows for non-Newtonian contributions to the force which might lead to a difference in the gravitational force on matter and antimatter. While it is widely expected that the gravitational interaction of matter and of antimatter should be identical, this assertion has never been tested experimentally. With the production of large amounts of cold antihydrogen at the CERN Antiproton Decelerator, such a test with neutral antimatter atoms has now become feasible. For this purpose, we have proposed to set up the AEGIS experiment at CERN/AD, whose primary goal will be the direct measurement of the Earth’s gravitational acceleration on antihydrogen with a classical Moiré deflectometer.  相似文献   
47.
The goal of the fungal mitochondrial genome project (FMGP) is to sequence complete mitochondrial genomes for a representative sample of the major fungal lineages; to analyze the genome structure, gene content, and conserved sequence elements of these sequences; and to study the evolution of gene expression in fungal mitochondria. By using our new sequence data for evolutionary studies, we were able to construct phylogenetic trees that provide further solid evidence that animals and fungi share a common ancestor to the exclusion of chlorophytes and protists. With a database comprising multiple mitochondrial gene sequences, the level of support for our mitochondrial phylogenies is unprecedented, in comparison to trees inferred with nuclear ribosomal RNA sequences. We also found several new molecular features in the mitochondrial genomes of lower fungi, including: (1) tRNA editing, which is the same type as that found in the mitochondria of the amoeboid protozoan Acanthamoeba castellanii; (2) two novel types of putative mobile DNA elements, one encoding a site-specific endonuclease that confers mobility on the element, and the other constituting a class of highly compact, structured elements; and (3) a large number of introns, which provide insights into intron origins and evolution. Here, we present an overview of these results, and discuss examples of the diversity of structures found in the fungal mitochondrial genome.  相似文献   
48.
During the foreperiod of a forewarned reaction time (RT) task reflexes in the executing limb increase to a lesser extent than those in the contralateral limb. This is possibly due to input modulation. The present study investigates the possibility of cutaneous sensory modulation during motor preparation by studying the amplitudes of somatosensory evoked potentials (SEPs). Eighteen subjects performed a forewarned RT task with the same fingers as the ones which were electrically stimulated. SEPs evoked during the 4 sec preparatory period were compared to those evoked during movement execution and during the resting period after the motor response respectively. During response execution most SEP components showed smaller amplitudes, i.e., they were gated, which agrees with other studies. In the first part of the foreperiod no SEP modulation was observed. Towards the end of the foreperiod, 500 msec before the response stimulus (RS), the amplitude of the contralateral parietal N70-P100 was significantly decreased, while the P45-N70 showed a similar tendency. However, at the same time the P100-N140 was increased in amplitude. The decrease of the intermediate latency components towards the end of the foreperiod is discussed in terms of gating, while the increase in the long latency component is discussed with respect to a decrease in RT on trials where the fingers were stimulated just before the RS, pointing to the role of attentional mechanisms.  相似文献   
49.
We characterized 11.7 fs nearly perfect Fourier Transform pulses with self-referenced spectral interferometry (SRSI), a new recently demonstrated technique. These pulses were first precisely optimized with three feedback loops between the SRSI setup and an AOPDF. An inherent control criterion to confirm that the measurement quality is theoretically derived and experimentally demonstrated. Each experimental result was cross-checked with SPIDER.  相似文献   
50.
Mechanics of Time-Dependent Materials - The aim of this work consists in estimating and modeling the viscoelastic behavior at small strain of KetaSpire® KT-880 PEEK fiber composites reinforced...  相似文献   
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