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Delft, Netherlands

Bogdan Staszewski R.,Dimes Inc
Proceedings - IEEE International Symposium on Circuits and Systems | Year: 2011

The past several years have successfully brought all-digital techniques to the RF frequency synthesis, which is used for frequency translation between the baseband and RF frequencies in wireless transmitters and receivers. Reference [1] has described the recent journey of digitizing RF frequency synthesizers, such that now they are amenable to nanoscale CMOS technology with area, power and performance metrics well exceeding those of the traditional charge-pump PLL's. This paper examines an important aspect of the all-digital frequency synthesizers, which takes on some of the transmitter functionality by allowing to directly perform the carrier frequency modulation. This is useful in today's wireless system, which either completely rely on the frequency modulation to convey the information or use it as part of a polar vector modulation. A novel multi-rate polar transmitter is proposed in which the modulating data rate is independent from the reference frequency. © 2011 IEEE. Source

Zhuang J.,AMD Inc | Waheed K.,Bitwave Inc. | Staszewski R.B.,Dimes Inc
IEEE Transactions on Circuits and Systems I: Regular Papers | Year: 2010

A polar modulator for wireless RF transmitters nonlinearly transforms complex-valued Cartesian baseband modulating signal into amplitude and phase components of the polar coordinate representation before they are recombined in a power amplifier. The resulting explosion in the bandwidth requirements of the polar components can so far be only tolerated for narrowband transmitters, such as EDGE of the 2G cellular. To enable polar topology for wideband transmitters, we propose a technique that alters the signal trajectory such that it avoids crossing (and proximity) of the constellation origin. The resulting substantial decrease of the polar modulator bandwidth is traded off against slight increase of in-band modulation distortion and adjacent channel leakage. We illustrate effectiveness of this method using wideband CDMA (WCDMA) of the 3G cellular. The technique is first mathematically analyzed for various tradeoffs followed by high-level modeling and simulation results. Since the technique is fully contained in the digital domain, its performance effects on the entire RF transmitter can be accurately simulated. A digital architecture to implement the proposed technique is also presented. © 2006 IEEE. Source

Dimes Inc | Date: 2007-03-14

Computer hardware and peripherals, and manuals all sold as a unit; computer software, namely, a browser toolbar for use in identifying, organizing and carrying out environmentally friendly activities. Providing on-line forums for the transmission of messages among computer users concerning the top ten things individuals can do to change the world in a positive way and improve the environment, and thereby enabling individuals to create, organize and engage in environmentally friendly activities; Providing on-line chat rooms and electronic bulletin boards for transmission of messages among users in the field of general interest; providing an online forum for transmission of messages among computer users for discussion and debate regarding issues and activities that impact the environment and people in developing countries; Providing on-line chat rooms for transmission of messages among and between computer users concerning activities that individuals can engage in to protect and improve the environment, and to assist individuals in developing countries to establish and operate businesses and engage in international trade. Online journals, namely, blogs featuring ideas for and activities that people can engage in to protect and improve the environment, assist individuals in developing countries to establish businesses and engage in international trade. Environmental services, namely, technical consultation in the field of environmental science, and designing and testing of new environmentally friendly products for others; enabling individuals to reduce the amount of unsolicited mail, advertising, promotional brochures, catalogues and related items from being delivered to them, by enabling individuals to subscribe to a service by which such materials are screened and prevented from being delivered.

Dimes Inc | Date: 2007-04-06

Series of books instructing in the playing, methodology and psychology of poker and gaming.

Coradeghini R.,JRC European Commission Institute for Health and Consumer Protection | Guida C.,University of Genoa | Scanarotti C.,Dimes Inc | Sanguineti R.,Dimes Inc | And 4 more authors.
Cells Tissues Organs | Year: 2010

Human adipose-derived stem cells possess a lot of stem cell characteristics, so they may be considered a source of stem cell population. On the basis of that, we have investigated the hepatic potential of adipose-derived stem cells, obtained from liposuction, following two differentiation protocols. In the first procedure, medium was supplemented with epidermal growth factor (EGF), basic fibroblast growth factor, hepatocyte growth factor (HGF) and nicotinamide; the second involved the addition of factors such as dexametasone, EGF, insulin-transferrin-sodium selenite, HGF, dimethyl sulfoxide and oncostatin. In parallel, we carried out our study in the Hep G2 cell line, as human hepatic differentiated in vitro model. Immunocytochemical analysis and RT-PCR were performed using hepatic markers to evaluate cell differentiation. DNA content, MTT test and carboxyl fluorescein succinimidyl ester staining were carried out to evaluate cell proliferation. We reported the evidence of basal hepatic marker in undifferentiated adipose-derived stem cells, which confirmed their multipotency. A strong expression of albumin and α-fetoprotein was observed in hepatic-induced adipose-derived stem cells following both differentiation procedures. Morphological aspects of the two types of hepatic adipose-derived stem cells were alike. Proliferation index suggested that the first differentiation procedure promoted better growth than the second. These preliminary findings suggest adipose-derived stem cells may be induced into hepatic lineage, and the most significant difference between the two standard differentiation procedures concerns proliferation rate. This aspect is to be considered when adipose-derived stem cells are employed in research and clinical studies. Copyright © 2009 S. Karger AG, Basel. Source

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