2,250 research outputs found
CRISPR activation screening of dormant genes to improve secretory capacity in CHO cells
Please click Additional Files below to see the full abstract
Enhancing CHO cell productivity through a novel dual selection system using Aspg and Gs in glutamine free medium
Please click Additional Files below to see the full abstract
Influence of Carbon Concentration on the Superconductivity in MgCxNi3
The influence of carbon concentration on the superconductivity (SC) in
MgCNi has been investigated by measuring the low temperature specific
heat combined with first principles electronic structure calculation. It is
found that the specific heat coefficient of the
superconducting sample () in normal state is twice that of the
non-superconducting one (). The comparison of measured
and the calculated electronic density of states (DOS) shows that the
effective mass renormalization changes remarkably as the carbon concentration
changes. The large mass renormalization for the superconducting sample and the
low (7K) indicate that more than one kind of boson mediated
electron-electron interactions exist in MgCNi.Comment: 4 pages, 4 figure
3D Geometrical Inspection of Complex Geometry Parts Using a Novel Laser Triangulation Sensor and a Robot
This article discusses different non contact 3D measuring strategies and presents a model for measuring complex geometry parts, manipulated through a robot arm, using a novel vision system consisting of a laser triangulation sensor and a motorized linear stage. First, the geometric model incorporating an automatic simple module for long term stability improvement will be outlined in the article. The new method used in the automatic module allows the sensor set up, including the motorized linear stage, for the scanning avoiding external measurement devices. In the measurement model the robot is just a positioning of parts with high repeatability. Its position and orientation data are not used for the measurement and therefore it is not directly “coupled” as an active component in the model. The function of the robot is to present the various surfaces of the workpiece along the measurement range of the vision system, which is responsible for the measurement. Thus, the whole system is not affected by the robot own errors following a trajectory, except those due to the lack of static repeatability. For the indirect link between the vision system and the robot, the original model developed needs only one first piece measuring as a “zero” or master piece, known by its accurate measurement using, for example, a Coordinate Measurement Machine. The strategy proposed presents a different approach to traditional laser triangulation systems on board the robot in order to improve the measurement accuracy, and several important cues for self-recalibration are explored using only a master piece. Experimental results are also presented to demonstrate the technique and the final 3D measurement accuracy
Triple negative breast carcinoma is a prognostic factor in Taiwanese women
© 2009 Lin et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens
Estimating ground-level PM 2.5 in eastern China using aerosol optical depth determined from the GOCI satellite instrument
We determine and interpret fine particulate matter (PM2.5)
concentrations in eastern China for January to December 2013 at a horizontal
resolution of 6 km from aerosol optical depth (AOD) retrieved from the
Korean geostationary ocean color imager (GOCI) satellite instrument. We
implement a set of filters to minimize cloud contamination in GOCI AOD.
Evaluation of filtered GOCI AOD with AOD from the Aerosol Robotic Network
(AERONET) indicates significant agreement with mean fractional bias (MFB) in
Beijing of 6.7 % and northern Taiwan of −1.2 %. We use a global chemical
transport model (GEOS-Chem) to relate the total column AOD to the
near-surface PM2.5. The simulated PM2.5 / AOD ratio exhibits high
consistency with ground-based measurements in Taiwan (MFB = −0.52 %) and
Beijing (MFB = −8.0 %). We evaluate the satellite-derived PM2.5
versus the ground-level PM2.5 in 2013 measured by the China
Environmental Monitoring Center. Significant agreement is found between
GOCI-derived PM2.5 and in situ observations in both annual averages
(r2 = 0.66, N = 494) and monthly averages (relative RMSE = 18.3 %),
indicating GOCI provides valuable data for air quality studies in Northeast
Asia. The GEOS-Chem simulated chemical composition of GOCI-derived
PM2.5 reveals that secondary inorganics (SO42-,
NO3-, NH4+) and organic matter are the most significant
components. Biofuel emissions in northern China for heating increase the
concentration of organic matter in winter. The population-weighted
GOCI-derived PM2.5 over eastern China for 2013 is 53.8 μg m−3, with 400 million residents in regions that exceed the Interim
Target-1 of the World Health Organization
Sun Tracking Systems: A Review
The output power produced by high-concentration solar thermal and photovoltaic systems is directly related to the amount of solar energy acquired by the system, and it is therefore necessary to track the sun's position with a high degree of accuracy. Many systems have been proposed to facilitate this task over the past 20 years. Accordingly, this paper commences by providing a high level overview of the sun tracking system field and then describes some of the more significant proposals for closed-loop and open-loop types of sun tracking systems
Thermal Conductivity of Carbon Nanotubes and their Polymer Nanocomposites: A Review
Thermally conductive polymer composites offer new possibilities for replacing metal parts in several applications, including power electronics, electric motors and generators, heat exchangers, etc., thanks to the polymer advantages such as light weight, corrosion resistance and ease of processing. Current interest to improve the thermal conductivity of polymers is focused on the selective addition of nanofillers with high thermal conductivity. Unusually high thermal conductivity makes carbon nanotube (CNT) the best promising candidate material for thermally conductive composites. However, the thermal conductivities of polymer/CNT nanocomposites are relatively low compared with expectations from the intrinsic thermal conductivity of CNTs. The challenge primarily comes from the large interfacial thermal resistance between the CNT and the surrounding polymer matrix, which hinders the transfer of phonon dominating heat conduction in polymer and CNT. This article reviews the status of worldwide research in the thermal conductivity of CNTs and their polymer nanocomposites. The dependence of thermal conductivity of nanotubes on the atomic structure, the tube size, the morphology, the defect and the purification is reviewed. The roles of particle/polymer and particle/particle interfaces on the thermal conductivity of polymer/CNT nanocomposites are discussed in detail, as well as the relationship between the thermal conductivity and the micro- and nano-structure of the composite
- …