1,608 research outputs found
Estimation of time delay by coherence analysis
Using coherence analysis (which is an extensively used method to study the
correlations in frequency domain, between two simultaneously measured signals)
we estimate the time delay between two signals. This method is suitable for
time delay estimation of narrow band coherence signals for which the
conventional methods cannot be reliably applied. We show by analysing coupled
R\"ossler attractors with a known delay, that the method yields satisfactory
results. Then, we apply this method to human pathologic tremor. The delay
between simultaneously measured traces of Electroencephalogram (EEG) and
Electromyogram (EMG) data of subjects with essential hand tremor is calculated.
We find that there is a delay of 11-27 milli-seconds () between the tremor
correlated parts (cortex) of the brain (EEG) and the trembling hand (EMG) which
is in agreement with the experimentally observed delay value of 15 for the
cortico-muscular conduction time. By surrogate analysis we calculate error-bars
of the estimated delay.Comment: 21 pages, 8 figures, elstart.cls file included. Accepted for
publication in Physica
A three-dimensional viscous flow analysis for the helicopter tip vortex generation problem
The tip vortex flow field occurring in the vicinity of the tip region of a a helicopter rotor blade is a very complicated three-dimensional, viscous flow phenomenon. The details of the flow in the tip region can have a major effect in determining the generated rotor noise and can significantly affect the performance and dynamic loading of the rotor blade. The three-dimensional viscous subsonic tip vortex generation processes is investigated by a numerical procedure which allows spatial forward-marching integration, utilizing flow approximations from the velocity-decomposition approach of Briley and McDonald. The approach has been applied to compute the laminar and turbulent tip vortex flows for a constant thickness slab airfoil with a square tip, a constant thickness slab airfoil with a half round tip and a NACA 0012 airfoil with a half round tip. The basic mechanism of the tip vortex generation process as well as the prediction of vortex appearance, strength and secondary flow shown by the calculations are in qualitative agreement with experimental results
Trade liberalization and digital divide : an analysis of the Information Technology Agreement of WTO
This article reflects on the effectiveness of trade liberalization, as
envisaged in the Information Technology Agreement (ITA) of the WTO,
for promoting ICT use and production in developing countries. Based
on empirical evidence on global exports of ITA goods, and the
performance of different groups of ITA member countries and nonmember
countries a case has been made for complementing trade
liberalization with capacity building so that ITA becomes more attractive
to developing countries as an additional strategy to bridge the digital
divide. It has also been argued that substantial capabilities in ICT
production and use have been developed over the years by select
developing countries, which provide fresh opportunities for new ICT
policy for social and economic development. Against this background
the article makes the case for an e-South Framework Agreement that
facilitates the harnessing of southern capabilities through building new
system of ICT innovation, as a complement to ongoing North-South
initiatives, inter alia involving trade liberalization along with capacity
building to promote ICT use and production in developing countries.
Key Words: Trade liberalisation, Digital Divide, Information
Technology Agreement, WTO
JEL Classification: F 13, L 86, F 5
(E)-2-({2-[(E)-(HyÂdroxyÂimino)ÂmethÂyl]phenÂoxy}methÂyl)-3-o-tolylÂacrylonitrile
In the title compound, C18H16N2O2, the dihedral angle between the mean planes through the two benzene rings is 56.8 (6)°. The enoate group assumes an extended conformation. The hyÂdroxyÂethanimine group is essentially coplanar with the benzene ring, the largest deviation from the mean plane being 0.047 (1) Å for the hyÂdroxyÂimino O atom. In the crystal, the molÂecules are linked into cyclic centrosymmetric dimers with R
2
2(6) motifs via O—H⋯N hydrogen bonds
Use of linear low density polythene film for frozen fish packaging
Physical properties of linear low density polythene film of 60 gauge thickness and its suitability as packaging material in frozen fish industry was studied in comparison with conventional 100 gauge low density polythene film. Both were comparable in water vapor transmission rate both at 38°C and -20°C, overall migration test and :flexibility at low temperatures. ·Even though the tearing strength was inferior to the conventional one, it is of no significance in its use in frozen fish industry. The new film worked out to be more economical than the other one
Bone metastases in non-small cell lung cancer: A narrative review
Background and Objective: Bone metastases are common in patients with non-small cell lung cancer (NSCLC) and remain a significant source of morbidity, mortality, and diminished quality of life, despite the considerable progress made in the overall management of patients with metastatic NSCLC over the last decade. Understanding the molecular pathogenesis of bone metastases is critical to improving survival, preserving function, and managing symptoms in this patient population. The objective of our review is to provide a comprehensive review of the pathophysiology, clinical presentation, management, and factors predicting the development and prognosis of patients with NSCLC with bone metastases.
Methods: An online electronic search was performed on PubMed and Google Scholar of all English-language literature using combinations of the following keywords: bone metastases, non-small cell lung cancer, pathophysiology, skeletal related events, response to therapy, predictive factors, and immunotherapy. Bibliographies of identified papers were reviewed for additional articles of interest. Observational cohort, retrospective studies, randomized controlled trials (RCTs), meta-analyses, and review articles were examined for this review.
Key Content and Findings: Bone metastases in lung cancer patients remain a common occurrence, impacting morbidity, mortality, and quality of life. Patients with skeletal related events (SREs) have worse prognosis. There is data supporting use of bisphosphonates and/or denosumab, and these should be considered in all patients with bone metastases. Novel studies comparing the genomic alterations of skeletal metastases and primary tumors are needed. As therapy for patients with advanced disease evolves, more studies are needed to evaluate the interplay between immunotherapy and bone metastases, and in determining the response to treatment in bone.
Conclusions: Predicting development and progression of bone metastases could allow earlier and targeted therapy in patients with bone metastases. Predicting and evaluating response to conventional chemotherapy and immune checkpoint inhibitors in NSCLC patients with bone metastases remains an unmet need and merits further study
Iced and frozen storage characteristics of cultured Chanos chanos (Forskal)
Freshly harvested milk fish (Chanos chanos) were stored in crushed ice and their storage life estimated by following biochemical, bacteriological and organoleptic changes occurring during storage. Samples of the fish were withdrawn at various intervals of storage, quick frozen, glazed and held in frozen storage at-l8°C. Shelf-life in frozen storage was determined in relation to period of ice storage prior to freezing by determining biochemical and organoleptic characteristics up to 30 weeks
Spatial synchronization and extinction of species under external forcing
We study the interplay between synchronization and extinction of a species.
Using a general model we show that under a common external forcing, the species
with a quadratic saturation term in the population dynamics first undergoes
spatial synchronization and then extinction, thereby avoiding the rescue
effect. This is because the saturation term reduces the synchronization time
scale but not the extinction time scale. The effect can be observed even when
the external forcing acts only on some locations provided there is a
synchronizing term in the dynamics. Absence of the quadratic saturation term
can help the species to avoid extinction.Comment: 4 pages, 2 figure
Computational Modeling Program
An Integrated Product Team (IPT) has been formed at NASA Ames Research Center which has set objectives to investigate devices and processes suitable for meeting NASA requirements on ultrahigh performance computers, fast and low power devices, and high temperature wide bandgap materials. These devices may ultimately be sub-100nm feature-size. Processes and equipment must meet the stringent demands posed by the fabrication of such small devices. Until now, the reactors for Chemical Vapor Deposition (CVD) and plasma processes have been designed by trial and error procedures. Further, once the reactor is in place, optimum processing parameters are found through expensive and time-consuming experimentation. If reliable models are available that describe processes and the operation of the reactors, that chore would be reduced to a routine task while being a cost-effective option. The goal is to develop such a design tool, validate that tool using available data from current generation processes and reactors, and then use that tool to explore avenues for meeting NASA needs for ultrasmall device fabrication. Under the present grant, ARL/Penn State along with other IPT members has been developing models and computer code to meet IPT goals. Some of the accomplishments achieved during the first year of the grant are described in this repor
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