bluuebunny/crossref_metadata_2025_split huggingface dataset:
The pan‐European mobile radio system: Part I
Authors: Hanzo L. , Steele R. 
Published: September 2010

AbstractFollowing the launch of the Pan‐European digital mobile radio (GSM) system its salient features are summarised in this tutorial review [1,8]. Time Division Multiple Access (TDMA) with eight users per carrier is used at a multi‐user rate of 271 kbit/s, demanding a channel equaliser to combat dispersion. The error protected chip‐rate of the full‐rate traffic channels is 22.8 kbit/s, while in half‐rate channels is 11.4 kbit/s. There are two speech traffic channels, five different‐rate data traffic channels and 14 various control and signalling channels to support the system's operation. A moderately complex, 13 kbit/s Regular Pulse Excited speech codec with long term predictor (LTP) is used, combined with an embedded three‐class error correction codec and multi‐layer interleaving to provide sensitivity‐matched unequal error protection for the speech bits. An overall speech delay of 57.5 ms is maintained. Slow frequency hopping at 217 hops/s yields substantial performance gains for slowly moving pedestrians.
Asynchronous polarization diversity receivers for coherent optical communications: A performance review
Authors: Gini Fulvio , Luise Marco 
Published: September 2010

AbstractThe performance of coherent receivers in optical communication systems is impaired by polarization mismatchings between the received optical signal and the local laser field. One of the most effective techniques to cope with such a phenomenon is the use of polarization‐diversity receivers which, at the cost of a higher complexity in the optical front‐end and a small performance degradation, guarantee insensitivity to changes in the state of polarization of the received signal. The goal of this paper is twofold: firstly, we present here an exact theoretical analysis of balanced polarization‐diversity receivers for ASK, FSK or DPSK modulation schemes in the shot‐noise‐limited regime, deriving closed‐form expressions for the receiver Bit Error Rate (BER) of each of the cited modulations. Secondly, we assess the sensitivity of the same receivers to a slowly‐varying frequency detuning of the heterodyne laser, in order to allow for a well‐aimed design of the Automatic Frequency Control (AFC) circuit of the local laser. This work was performed in the Framework of the “Telecommunications” project funded by the Italian National Research Council (CNR).
Letter: Spacing of lumped amplifiers in soliton transmission
Authors: Carassa Francesco 
Published: September 2010

AbstractLumped amplifiers evenly spaced along a fiber represent a very important solution for attenuation compensation in the case of soliton transmission [1, 2, 6 ‐ 15]. This paper deals with the problem of evaluating (in the absence of noise) the maximum amplifier spacing compatible with the conditions for soliton propagation. The analysis is based on a simple approach to solitons, and it attains physical evidence by making reference to a well‐known property, i.e. that solitons in the lossless fiber [1 ‐ 5] are able to produce a continuous compensation between a modulation angle due to dispersion and a modulation angle due to non‐linearity. The first paragraph will illustrate the mentioned approach for the lossless fiber, which will be extended, in the last paragraph, to the attenuating fiber with lumped amplifiers.
Threshold cryptography
Authors: Desmedt Yvo G. 
Published: September 2010

AbstractIn the traditional scenario in cryptography there is one sender, one receiver and an active or passive eavesdropper who is an opponent. Large bank transactions require two people to sign, implying two senders. So the power to generate a valid transaction is shared. Threshold cryptography allows one to share the power of a cryptosystem. Threshold cryptosystems are distinct from threshold schemes in which the power to regenerate a secret key is shared. A normal threshold scheme is not directly suited for threshold signatures. Using a threshold scheme directly would require the shareholders to send their shares to a trusted person who would apply the cryptosystem for them. But the use of such a trusted person violates the main point of threshold cryptography. We motivate the need for treshold cryptosystems, overview the research in the field, and give some simple examples. We will conclude by giving a list of open problems.
VLSI implementation of a signal interpolator chip for high‐speed all‐digital data modems
Authors: Luise Marco , Roncella Roberto 
Published: September 2010

AbstractThis paper describes the structure of a signal interpolator chip to be used in medium‐to‐high data rate digital modems, based on the so‐called “Systolic Macrocells” design style. In particular, we focus on a third‐order polynomial interpolation algorithm, as a good trade‐off between the contrasting needs of high accuracy and low complexity/cost. We also present a concise description of the architecture of the chip through a functional description of the main basic systolic macrocells it is composed of. Despite the apparent complexity of the architecture, the basic cells of each bit‐level systolic array are remarkably simple and homogeneous: they are mainly composed by delays and summing elements such as full and half adders, so that their realization does not represent a difficult design task. The interpolator chip has been completely laid out assuming a 1.2 μ m CMOS technology and occupies a silicon area of 5 × 4.5 mm2, pad included. In particular, we envisage an operating clock frequency of 70 MHz, so that the chip can process sequences of 8 bit words at the rate of 17.5 MSamples/s with a power supply requirement of less than 0.5 W.
Transmission issues for HDTV satellite systems
Authors: Ferrari Marco , Castellani Valentino , Lo Cigno Renato , Losquadro Giacinto , Tabone Mirto 
Published: September 2010

AbstractThe transmission of digital HDTV signals on satellite channels in the 20–30 GHz band is studied with the aim of designing an Italian domestic satellite, both for the exchange of programs among production centers and for direct broadcasting to end‐users. Previous work on the definition of the system architecture and of the payloads is first briefly summarized. The transmission impairments due to the interfered environment are then analyzed in detail and simulation studies are reported. The results confirm the choices made for the link budgets during the system configuration design. Experimental tests carried out both with laboratory simulators and with the Olympus European satellite are finally described.
An adaptive DSP predistortion technique for radio systems
Authors: Visintin Monica 
Published: September 2010

AbstractA simple implementation of an analog predistorter for nonlinear HPA is described. Good performance is obtainable in terms of BER, and bandwidth occupancy of the signal after the amplifier. The described technique is independent of the modulation format and of the filter characteristics. Results are given for 16‐QAM and 64‐QAM modulation schemes.
Robust vector quantization for noisy channels using soft decision and sequential decoding
Authors: Cuperman Vladimir , Liu Feng‐Hua , Ho Paul 
Published: September 2010

AbstractThis paper considers the optimization of a vector quantizer whose indices are transmitted over a channel with known noise statistics (pdf). A decoder is introduced which uses a linear combination of VQ codebook entries with weights depending on the received signal. Rather than using a received index to select an entry in the codebook (which implies a hard decision on the index), the decoder uses the received signal and the channel statistics to weight the codebook entries in order to produce a good reconstructed signal. Borrowing a term used in digital communications, we will say that the optimal decoder uses a “soft” decision rule. The corresponding approach will be called Soft Decision Vector Quantization (SDVQ). It is shown that SDVQ achieves a significant performance improvement over both the source optimized VQ and the channel optimized VQ (the latter is based on known channel transition probabilities). For correlated sources, it is shown that SDVQ performance can be further improved by using sequential decoding. Results are presented for an AR(1) source and for speech line spectral pair (LSP) parameter quantization at 24 bits/frame.
Letter: On uniform distance property of multilevel block 8‐PSK modulation
Authors: Hofmann Karl Heinrich 
Published: September 2010

AbstractFor upper bounding the word error probability of block codes by application of the union bound, in general the uniform distance property (distance invariance) of the code must be guaranteed. This property says that the distance spectrum of a code is independent of the choice of the reference codeword. In the sequel new sufficient conditions for multilevel block 8‐PSK modulation codes to be distance invariant are derived.
Morphology and anatomy of anomalous short shoots in Pinus (Pinaceae) and their evolutionary meaning
Authors: Dörken Veit Martin , Stephan Gerrit , Stützel Thomas 
Published: September 2010

AbstractRecent Pinus ‐species are evergreen and have a typical long shoot/short shoot differentiation. For angiosperms we could show that this type of shoot differentiation is linked to deciduousness (Dörken & Stützel 2009). Evergreen angiosperms with prominent shoot differentiation are derived from deciduous ancestors. The primitive evergreen condition is however characterized by the absence of a shoot differentiation. Here it is therefore analysed if the shoot differentiation in Pinus could be regarded as a reminder of a deciduous ancestry. In such a context Pinus monophylla would be functionally closest to a primitive evergreen angiosperm and represent a nearly perfect secondary adaptation to the needs of an evergreen species. Morphology and anatomy of aberrant short shoots in Pinus ‐species have been analysed to test this hypothesis. We suppose that the ancestor of Pinus had several needle leaves inserted spirally on a well developed short shoot axis ending in a terminal bud, as it can be found in Larix today (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Origin of Potentilla crantzii, P. verna and P. puberula (Rosaceae) with a note on the nomenclature of P. pusilla
Authors: Soják Jiří 
Published: September 2010

AbstractThe mode of origin of Potentilla crantzii (quinate leaves) from the Asian P. gelida (ternate leaves) can be observed in Tien Shan and in mountains of southern Siberia even at present. Transitional forms between them also occur in the far North‐East of Asian Russia and from the Ural to Norway. Potentilla puberula (P. pusilla according to contemporary authors) did not originate by hybridization between P. incana (P. arenaria) and P. verna (P. tabernaemontani), as is usually assumed. On the contrary, P. verna is derived from the hybrid species P. puberula, i.e., from the offspring of crosses between P. heptaphylla and P. incana. It arose from them by way of gradual loss of stellate and partly reduced stellate hairs. This process took place mainly in the past but may be documented reliably.The name P. pusilla Host 1831 has been used since 1949 for the hybrid plants mentioned. The monographer of the genus Wolf (1908: 601) studied its type specimen and ascertained that it has only simple hairs, determining it as P. verna L. The type specimen of P. pusilla is currently lost. The name is doubtful. It is recommended herein to replaced it with the name P. puberula Krašan 1867 (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Numerical assessment of hydrodynamic characteristics in chlorine contact tank
Authors: Amini R. , Taghipour R. , Mirgolbabaei H. 
Published: September 2010

AbstractIn the present study, a three‐dimensional numerical approach is applied to simulate the velocity field and tracer experimental studies performed in a scaled‐down physical model of Embsay chlorine contact tank being used in U.K. It is found that the computational fluid dynamics (CFD) model could accurately predict the hydrodynamics of the tank so that, using the developed CFD models, further investigations are conducted in six tanks with different number of baffles to explore the effect of their numbers on the hydraulic characteristics of the unit. The results show the existence of recirculation areas behind the baffles in a way that the extension of these regions dwindles with increasing the number of baffles, leading the fluid flow to approach plug‐flow conditions. Baffle wall arrangement are conducted, to improve the unit's performance in terms of higher effective contact time (lower Morrill Index). The results from the new proposed arrangement with six baffle walls show an improvement of about 13% increase in effective contact time compared with that of the original baffle arrangement. Copyright © 2010 John Wiley & Sons, Ltd.
Fuel Cell Powered Vehicles Using Supercapacitors–Device Characteristics, Control Strategies, and Simulation Results
Authors: Zhao H. , Burke A. F. 
Published: September 2010

AbstractThe fuel cell powered vehicle is one of the most attractive candidates for the future due to its high efficiency and capability to use hydrogen as the fuel. However, its relatively poor dynamic response, high cost and limited life time have impeded its widespread adoption. With the emergence of large supercapacitors (also know as ultracapacitors, UCs) with high power density and the shift to hybridisation in the vehicle technology, fuel cell/supercapacitor hybrid fuel cell vehicles are gaining more attention. Fuel cells in conjunction with supercapacitors can create high power with fast dynamic response, which makes it well suitable for automotive applications. Hybrid fuel cell vehicles with different powertrain configurations have been evaluated based on simulations performed at the Institute of Transportation Studies, University of California‐Davis. The following powertrain configurations have been considered:(a)Direct hydrogen fuel cell vehicles (FCVs) without energy storage(b)FCVs with supercapacitors directly connected in parallel with fuel cells(c)FCVs with supercapacitors coupled in parallel with fuel cells through a DC/DC converter(d)FCVs with fuel cells connected to supercapacitorsviaa DC/DC converter
A prognostic DNA signature for T1T2 node‐negative breast cancer patients
Authors: Gravier Eléonore , Pierron Gaëlle , Vincent‐Salomon Anne , Gruel Nadège , Raynal Virginie , Savignoni Alexia , De Rycke Yann , Pierga Jean‐Yves , Lucchesi Carlo , Reyal Fabien , Fourquet Alain , Roman‐Roman Sergio , Radvanyi François , Sastre‐Garau Xavier , Asselain Bernard , Delattre Olivier 
Published: September 2010

AbstractPredicting evolution of small node‐negative breast carcinoma is a real challenge in clinical practice. The aim of this study was to search whether qualitative or quantitative DNA changes may help to predict metastasis of small node‐negative breast carcinoma. Small invasive ductal carcinomas without axillary lymph node involvement (T1T2N0) from 168 patients with either good (111 patients with no event at 5 years after diagnosis) or poor (57 patients with early metastasis) outcome were analyzed with comparative genomic hybridization (CGH) array. A CGH classifier, identifying low‐ and high‐risk groups of metastatic recurrence, was established in a training set of 78 patients, then validated, and compared with clinicopathological parameters in a distinct set of 90 patients. The genomic status of regions located on 2p22.2, 3p23, and 8q21‐24 and the number of segmental alterations were defined in the training set to classify tumors into low‐ or high‐risk groups. In the validation set, in addition to estrogen receptors and grade, this CGH classifier provided significant prognostic information in multivariate analysis (odds ratio, 3.34; 95% confidence interval 1.01–11.02; P = 4.78 × 10−2, Wald test). This study shows that tumor DNA contains important prognostic information that may help to predict metastasis in T1T2N0 tumors of the breast. © 2010 Wiley‐Liss, Inc.
Differential regulation of TP73 isoforms by 1α,25‐dihydroxyvitamin D3 and survivin in human colon and breast carcinomas
Authors: Díaz Raquel , González‐Sancho José M. , Soldevilla Beatriz , Silva Javier , García José M. , García Vanesa , Peña Cristina , Herrera Mercedes , Gómez Irene , Bonilla Félix , Domínguez Gemma 
Published: September 2010

AbstractWe evaluate whether 1,25(OH)2D3 downregulates TP73 variants in colon and breast carcinomas, the role of survivin in this context, and the significance of this network in the clinic. Tumor cells were treated/untreated with 1,25(OH)2D3 and transiently transfected with survivin. Levels of survivin and TP73 variants were evaluated by quantitative RT‐PCR and Western blotting. In 75 colon and 60 breast cancer patients, the expressions of survivin and TP73 isoforms were determined. Tumor characteristics were examined in each patient. Survivin protein levels were also evaluated in a subgroup of patients and cell lines. Decrease in survivin and TAp73 transcripts and protein and ΔNp73 mRNA was detected after 1,25(OH)2D3 treatment. Ectopic survivin expression led to an increase in the TAp73, ΔNp73, ΔEx2p73, and ΔEx2‐3p73 transcripts. In cancer patients, direct correlations were observed between TP73 variants and survivin levels. 1,25(OH)2D3 negatively regulate survivin and TP73 variants in colon and breast cancer cells. Positive regulation of TP73 isoforms by survivin may exist, which reinforces the possibility that the downregulation of TP73 forms by 1,25(OH)2D3 is survivin‐dependent. © 2010 Wiley‐Liss, Inc.
A formalized approach to analysis of geoarchaeological sediment samples: The location of the early punic Harbor at Carthage, Tunisia
Authors: Vitali V. , Gifford J. A. , Djindjian F. , Rapp G. 
Published: September 2010

AbstractThis article concerns, first, the development of an approach to data analysis of sedimentological, micro‐ and macrofaunal, and artifactual data obtained from analysis of geoarchaeological sediment core samples and, second, an algorithmic ordering of resulting sediment groups to arrive at a definitive stratigraphic sequence. Correspondence analysis (CA) was the principal data analysis technique applied, and the algorithmic ordering is one developed for discrete sampling sequences such as core transects. From a methodological standpoint, this approach allows an assessment of the usefulness of different types of analytical information pertaining to a paleoenvironmental reconstruction of a coastal archaeological site. In terms of the geoarchaeological problem that initiated the study, the results permit a possible reconstruction of the location and nature of the first Punic port at Carthage, Tunisia.
Testing for non‐random mating: evidence for ancestry‐related assortative mating in the Framingham heart study
Authors: Sebro Ronnie , Hoffman Thomas J. , Lange Christoph , Rogus John J. , Risch Neil J. 
Published: September 2010

AbstractPopulation stratification leads to a predictable phenomenon—a reduction in the number of heterozygotes compared to that calculated assuming Hardy‐Weinberg Equilibrium (HWE). We show that population stratification results in another phenomenon—an excess in the proportion of spouse‐pairs with the same genotypes at all ancestrally informative markers, resulting in ancestrally related positive assortative mating. We use principal components analysis to show that there is evidence of population stratification within the Framingham Heart Study, and show that the first principal component correlates with a North‐South European cline. We then show that the first principal component is highly correlated between spouses (r = 0.58, p = 0.0013), demonstrating that there is ancestrally related positive assortative mating among the Framingham Caucasian population. We also show that the single nucleotide polymorphisms loading most heavily on the first principal component show an excess of homozygotes within the spouses, consistent with similar ancestry‐related assortative mating in the previous generation. This nonrandom mating likely affects genetic structure seen more generally in the North American population of European descent today, and decreases the rate of decay of linkage disequilibrium for ancestrally informative markers. Genet. Epidemiol. 34: 674‐679, 2010. © 2010 Wiley‐Liss, Inc.
Neurocognitive perspectives in language outcomes of Early Head Start: Language and cognitive stimulation and maternal depression
Authors: Chapin Laurie A. , Altenhofen Shannon 
Published: September 2010

AbstractA neurocognitive, developmental framework was used to examine the effectiveness of Early Head Start (EHS) programs. Evidence has shown that caregiver variables impact early brain development. This study aimed to better understand this relation. Results showed that the EHS program made no significant impact, and at 3 years old, children were significantly behind population norms in language development, partially replicating previous findings with children from poverty backgrounds. EHS and parental depression were significant predictors of language and cognitive stimulation; however, depression and stimulation, but not involvement in EHS, were significant predictors of vocabulary. Implications for EHS programs are discussed, such as addressing caregiver variables (e.g., depression) and increasing focus on services to expectant families. Future directions also are discussed, such as understanding how young children's stress, within the context of caregiver variables, is related to neurocognitive outcomes.
Maternal depression and parental distress among families in the Early Head Start Research and Evaluation Project: Risk factors within the family setting
Authors: Rafferty Yvonne , Griffin Kenneth W. , Robokos Dimitra 
Published: September 2010

AbstractThis study examined the influence of risk factors within the family environment (inadequate resources, insufficient caregiving support from child's father, higher family conflict) on maternal well being (depression and parental distress) using a longitudinal panel research design. Participants consisted of 2,040 low‐income mothers of young children enrolled in the Early Head Start (EHS) Research and Evaluation Project. Findings indicated that greater family resources at 14 months had a protective effect on maternal well‐being at 36 months, controlling for demographic variables and maternal well‐being at 14 months. Furthermore, the effect of family resources on maternal well‐being was moderated by father caregiving support, such that family resources were protective, particularly when father caregiving support was lower. Family conflict at 14 months was associated with lower maternal well‐being at 36 months, controlling for demographic variables and maternal well‐being at 14 months. Our findings suggest that low‐income mothers need the support and resources of programs such as EHS to overcome the hurdles and challenges of parenting in high‐risk settings. Implications for clinical practice and EHS are discussed.