435 research outputs found
Management of Women — Risk or Opportunity?
A lot has been written about women. Throughout human civilization women have been the foundation of families, but also wars were waged over women, and through marriages friendships were created or expanded, agreements forged between friends, etc. Even today women are the entity, without which one can not imagine the existence of the universe. In other words, evolution is a process in which cells (male and female) are connected resulting in growth and development, but also in the ability to connect with other cells which
leads to the formation of living beings, including man as the most complex living being which operates on the principles of selforganization. However, when it comes to politics, business and the general performance of complex and traditional activities that are practiced by men, women are marginalized and discriminated against on numerous issues. Stereotypes and negative attitudes toward business women or women managers have been carefully maintained over centuries. Not far from the truth is statement according to which women must be
twice as good as men, to take up important positions in organizations. The aim of this paper is to point out certain indisputable facts when it comes to female management and to answer the question of whether female management is a risk or a chance
New contribution to the research of the theory of whole
Although a whole as a phenomenon was entertained by ancient Chinese wiesemen, it seems that this issue remains in the focus of the modern world too, and especially of social, and organizational sciences. However, any, even the science of organization and management has its theoretical basis. Without a theory that has been confirmed in practice, no science can get the title of science. Therefore, any contribution to the study of the theory of a whole has practical value, and if not, it is an utopia, something that is impossible and unattainable in the real world. The beliefs that in perspective the theory of a whole shall gain even greater importance are quite realistic, which is logical, because life, work and business keep getting more and more complex, with increased interdependence between relationships, and with increases of both speed and dynamics of life and work. The aim of this paper is to draw attention to new thoughts and ideas about the theory of a whole, and all for the purpose of its application in the design and management of organizational and other systems
Electronic Devices Based on Purified Carbon Nanotubes Grown By High Pressure Decomposition of Carbon Monoxide
The excellent properties of transistors, wires, and sensors made from
single-walled carbon nanotubes (SWNTs) make them promising candidates for use
in advanced nanoelectronic systems. Gas-phase growth procedures such as the
high pressure decomposition of carbon monoxide (HiPCO) method yield large
quantities of small diameter semiconducting SWNTs, which are ideal for use in
nanoelectronic circuits. As-grown HiPCO material, however, commonly contains a
large fraction of carbonaceous impurities that degrade properties of SWNT
devices. Here we demonstrate a purification, deposition, and fabrication
process that yields devices consisting of metallic and semiconducting nanotubes
with electronic characteristics vastly superior to those of circuits made from
raw HiPCO. Source-drain current measurements on the circuits as a function of
temperature and backgate voltage are used to quantify the energy gap of
semiconducting nanotubes in a field effect transistor geometry. This work
demonstrates significant progress towards the goal of producing complex
integrated circuits from bulk-grown SWNT material.Comment: 6 pages, 4 figures, to appear in Nature Material
Monte Carlo study of coaxially gated CNTFETs: capacitive effects and dynamic performance
Carbon Nanotube (CNT) appears as a promising candidate to shrink field-effect
transistors (FET) to the nanometer scale. Extensive experimental works have
been performed recently to develop the appropriate technology and to explore DC
characteristics of carbon nanotube field effect transistor (CNTFET). In this
work, we present results of Monte Carlo simulation of a coaxially gated CNTFET
including electron-phonon scattering. Our purpose is to present the intrinsic
transport properties of such material through the evaluation of electron
mean-free-path. To highlight the potential of high performance level of CNTFET,
we then perform a study of DC characteristics and of the impact of capacitive
effects. Finally, we compare the performance of CNTFET with that of Si nanowire
MOSFET.Comment: 15 pages, 14 figures, final version to be published in C. R. Acad.
Sci. Pari
COMORBIDITY IMPACT ON SOCIAL FUNCTIONING AFTER HIP FRACTURE: THE ROLE OF REHABILITATION
Field-effect transistors assembled from functionalized carbon nanotubes
We have fabricated field effect transistors from carbon nanotubes using a
novel selective placement scheme. We use carbon nanotubes that are covalently
bound to molecules containing hydroxamic acid functionality. The functionalized
nanotubes bind strongly to basic metal oxide surfaces, but not to silicon
dioxide. Upon annealing, the functionalization is removed, restoring the
electronic properties of the nanotubes. The devices we have fabricated show
excellent electrical characteristics.Comment: 5 pages, 6 figure
Configurable LDPC Decoder Architecture for Regular and Irregular Codes
Low Density Parity Check (LDPC) codes are one of the best error correcting codes that enable the future generations of wireless devices to achieve higher
data rates with excellent quality of service. This paper presents two novel flexible decoder architectures. The first one supports (3, 6) regular codes of rate 1/2 that can be used for different block lengths. The second decoder is more general and supports both regular and irregular LDPC codes with twelve combinations of code lengths −648, 1296, 1944-bits and code rates-1/2, 2/3, 3/4, 5/6- based on the IEEE 802.11n standard. All codes correspond to a block-structured parity check matrix, in which the sub-blocks are either a shifted identity matrix or a zero matrix. Prototype architectures for both LDPC decoders have been implemented and tested on a Xilinx field programmable gate array.NokiaNational Science Foundatio
Carbon Nanotube Field-Effect Transistors With Integrated Ohmic Contacts and High-k Gate Dielectrics
High performance enhancement mode semiconducting carbon nanotube field-effect
transistors (CNTFETs) are obtained by combining ohmic metal-tube contacts, high
dielectric constant HfO2 films as gate insulators, and electrostatically doped
nanotube segments as source/drain electrodes. The combination of these elements
affords high ON currents, subthreshold swings of ~ 70-80 mV/decade, and allows
for low OFF currents and suppressed ambipolar conduction. The doped source and
drain approach resembles that of MOSFETs and can impart excellent OFF states to
nanotube FETs under aggressive vertical scaling. This presents an important
advantage over devices with metal source/drain, or devices commonly referred to
as Schottky barrier FETs
Low-frequency Current Fluctuations in Individual Semiconducting Single-Wall Carbon Nanotubes
We present a systematic study on low-frequency current fluctuations of
nano-devices consisting of one single semiconducting nanotube, which exhibit
significant 1/f-type noise. By examining devices with different switching
mechanisms, carrier types (electrons vs. holes), and channel lengths, we show
that the 1/f fluctuation level in semiconducting nanotubes is correlated to the
total number of transport carriers present in the system. However, the 1/f
noise level per carrier is not larger than that of most bulk conventional
semiconductors, e.g. Si. The pronounced noise level observed in nanotube
devices simply reflects on the small number of carriers involved in transport.
These results not only provide the basis to quantify the noise behavior in a
one-dimensional transport system, but also suggest a valuable way to
characterize low-dimensional nanostructures based on the 1/f fluctuation
phenomenon
Cellular expression, trafficking, and function of two isoforms of human ULBP5/RAET1G
Background:
The activating immunoreceptor NKG2D is expressed on Natural Killer (NK) cells and subsets of T cells. NKG2D contributes to anti-tumour and anti-viral immune responses in vitro and in vivo. The ligands for NKG2D in humans are diverse proteins of the MIC and ULBP/RAET families that are upregulated on the surface of virally infected cells and tumours. Two splicing variants of ULBP5/RAET1G have been cloned previously, but not extensively characterised.
Methodology/Principal Findings:
We pursue a number of approaches to characterise the expression, trafficking, and function of the two isoforms of ULBP5/RAET1G. We show that both transcripts are frequently expressed in cell lines derived from epithelial cancers, and in primary breast cancers. The full-length transcript, RAET1G1, is predicted to encode a molecule with transmembrane and cytoplasmic domains that are unique amongst NKG2D ligands. Using specific anti-RAET1G1 antiserum to stain tissue microarrays we show that RAET1G1 expression is highly restricted in normal tissues. RAET1G1 was expressed at a low level in normal gastrointestinal epithelial cells in a similar pattern to MICA. Both RAET1G1 and MICA showed increased expression in the gut of patients with celiac disease. In contrast to healthy tissues the RAET1G1 antiserum stained a wide variety or different primary tumour sections. Both endogenously expressed and transfected RAET1G1 was mainly found inside the cell, with a minority of the protein reaching the cell surface. Conversely the truncated splicing variant of RAET1G2 was shown to encode a soluble molecule that could be secreted from cells. Secreted RAET1G2 was shown to downregulate NKG2D receptor expression on NK cells and hence may represent a novel tumour immune evasion strategy.
Conclusions/Significance:
We demonstrate that the expression patterns of ULBP5RAET1G are very similar to the well-characterised NKG2D ligand, MICA. However the two isoforms of ULBP5/RAET1G have very different cellular localisations that are likely to reflect unique functionality
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