bluuebunny/crossref_metadata_2025_split huggingface dataset:
Low‐power quadrature generators for body area network applications
Authors: Masuch Jens , Delgado‐Restituto Manuel 
Published: October 2011

SUMMARYThis paper presents different alternatives for the implementation of low‐power monolithic oscillators for wireless body area networks and describes the design of two quadrature generators operating in the 2.4‐GHz frequency range. Both implementations have been designed in a 90‐nm Complementary Metal‐Oxide Semiconductor (CMOS) technology and operate at 1 V of supply voltage. The first architecture uses a voltage‐controlled oscillator (VCO) running at twice the desired output frequency followed by a divider‐by‐2 circuit. It experimentally consumes 335 μW and achieves a phase noise of −110.2 dBc/Hz at 1 MHz. The second architecture is a quadrature VCO that uses reinforced concrete phase shifters in the coupling path for phase noise improvement. Its power consumption is only 210 μW, and it obtains a phase noise of −111.9 dBc/Hz at 1 MHz. Copyright © 2011 John Wiley & Sons, Ltd.
Formulating hybrid equations and state equations for nonlinear circuits using SPICE
Authors: Yamamura Kiyotaka , Tonokura Mitsuru 
Published: October 2011

SUMMARYHybrid equations are often used in the theoretical study of nonlinear resistive circuits because they have an easy‐to‐analyze structure. They are also advantageous in the numerical analysis of nonlinear resistive circuits because they are separable and consist of a relatively small number of variables. However, the hybrid equations are seldom used in practical applications because their formulation is complicated. In this letter, we propose a simple method for formulating the hybrid equations using SPICE. In the proposed method, we only perform the transient analysis of SPICE on a linear circuit that is obtained through a small modification to the original circuit. It is also shown that state equations for nonlinear dynamic circuits can also be formulated by using the proposed method. Copyright © 2011 John Wiley & Sons, Ltd.
Design of a contactless power charger for a functional jacket
Authors: Lu Yan , Cheng Ka Wai Eric , Wang Shuxiao , Ding Kai , Kwok Kin Wing 
Published: October 2011

SUMMARYThis paper presents a contactless power charger for a functional jacket. The contactless power conversion, using the contactless power transformer, is examined. The primary and secondary sides of the transformer are separated by a large air gap, and hence, the power transfer can be obtained without physical contact. The characteristics of the gapped transformer and the compensation methodology on both the primary side and secondary side, are investigated in detail. The contactless power converter using phase‐locked loop control is presented. Experiments and results are disclosed. Copyright © 2011 John Wiley & Sons, Ltd.
A 5‐GHz energy‐efficient tunable pulse generator for ultra‐wideband applications using a variable attenuator for pulse shaping
Authors: El‐Gabaly Ahmed M. , Saavedra Carlos E. 
Published: October 2011

SUMMARYA new energy‐efficient tunable pulse generator is presented in this paper using 0.13‐µm CMOS technology for short‐range high‐data‐rate 3.1–10.6 GHz ultra‐wideband applications. A ring oscillator consisting of current‐starved CMOS inverters is quickly switched on and off for the duration of the pulse, and the amplitude envelope is shaped with a variable passive CMOS attenuator. The variable passive attenuator is controlled using an impulse that is created by a low‐power glitch generator (CMOS NOR gate). The glitch generator combines the falling edge of the clock and its delayed inverse, allowing the duration of the impulse to be changed over a wide range (500–900 ps) by varying the delay between the edges. The pulses generated with this technique can provide a sharp frequency roll off with high out‐of‐band rejection to help meet the Federal Communications Commission mask. The entire circuit operates in switched mode with a low average power consumption of less than 3.8 mW at 910 MHz pulse repetition frequency or below 4.2 pJ of energy per pulse. It occupies a total area of 725 × 600 µm2 including bonding pads and decoupling capacitors, and the active circuit area is only 360 × 200 µm2. Copyright © 2011 John Wiley & Sons, Ltd.
Investigation of possible ferroresonance for a voltage range: realisation of a system event with a laboratory set‐up
Authors: Miličević Kruno , Emin Zia 
Published: October 2011

SUMMARYThe paper presents an analytical and numerical investigation carried out on part of an electrical power network exhibiting ferroresonant behaviour as well as experimental investigation on its physical model. The investigations were carried out in order to estimate the extent of predicting the range of voltage source amplitude values at which the initiation of ferroresonance depends on values of initial conditions and phase shift. For this range of voltage source amplitude values (termed as possible ferroresonant range in the paper), the impact of initial conditions and phase shift of voltage source on the initiation of ferroresonance is determined using a numerical investigation and an experimental set‐up. Reasons and consequences of disagreement of parameter values of the original and physical model are determined. Copyright © 2011 John Wiley & Sons, Ltd.
Generation of Ppp2Ca and Ppp2Cb conditional null alleles in mouse
Authors: Gu Pengyu , Qi Xin , Zhou Yue , Wang Yun , Gao Xiang 
Published: October 2011

AbstractProtein phosphatase 2A (PP2A) is one of the most abundant serine/threonine phosphatases, with a critical role in embryonic development and human disease. There are two isoforms of the catalytic subunit of PP2A, Ppp2ca and Ppp2cb. Null mutation of Ppp2ca leads to early embryonic lethality at E6.5, hindering functional study of PP2A beyond this stage. We generated conditional null alleles of Ppp2ca and Ppp2cb by flanking with loxP sites exons 3 to 5 of Ppp2ca and exon 3 of Ppp2cb. Ppp2cafl/fl mice did not display any visible phenotype. Homozygous mutants in which Cre‐mediated excision resulted in global deletion of Ppp2ca displayed embryonic lethality and developmental defects similar to those previously reported. Ppp2cbΔ/Δ mice generated by the same strategy did not display any obvious morphological or physiological defects. These mouse strains can serve as important genetic tools to study the roles of PP2A during development and disease in a spatial‐ or temporal‐specific manner. genesis 50:429–436, 2012. © 2011 Wiley Periodicals, Inc.
Identification ofBombyx atonaland functional comparison with theDrosophila atonalproneural factor in the developing fly eye
Authors: Yu Linlin , Zhou Qingxiang , Zhang Chuanxi , Pignoni Francesca 
Published: October 2011

AbstractThe proneural genes are fundamental regulators of neuronal development in all metazoans. A critical role of the fly proneural factor Atonal (AtoDm) is to induce photoreceptor neuron formation inDrosophila, whereas its murine homolog, Atonal7Mm(aka Ath5) is essential for the development of the ganglion cells of the vertebrate eye. Here, we identify theBombyx mori atohomolog (atoBm). In a pattern strikingly reminiscent ofatoDm, theatoBmmRNA is expressed as a stripe in the silkworm eye disc. Its DNA‐binding and protein‐protein interaction domain is highly homologous to the AtoDmbHLH. Targeted expression of AtoBmin the endogenousatoDmpattern rescues the eyeless phenotype of the flyato1mutant and its ectopic expression induces similar gain‐of‐function phenotypes as AtoDm. Rescue experiments with chimeric proteins show that the non‐bHLH portion of AtoBm(N‐region) can effectively substitute for the corresponding region of the fly transcription factor, even though no apparent conservation can be found at the amino acid level. On the contrary, the highly similar bHLH domain of AtoBmcannot similarly substitute for the corresponding region of AtoDm. Thus, the bHLHBmdomain requires the AtoBmN‐region to function effectively, whereas the bHLHDmdomain can operate well with either N‐region. These findings suggest a role for the non‐bHLH portion of Ato proteins in modulating the function of the bHLH domain in eye neurogenesis and implicate specific aa residues of the bHLH in this process. genesis 50:393–403, 2012. © 2011 Wiley Periodicals, Inc.
Electrochemiluminescence DNA Sensor Based on Hairpin Structure DNA as recognition element and Ru(bpy)32+‐doped silica Nanoparticles as Signal‐Producing Compound
Authors: Sun Qixia , Zou Guizheng , Zhang Xiaoli 
Published: October 2011

AbstractAn electrochemiluminescence (ECL) DNA sensor was presented using a hairpin structure DNA as recognition element and Ru(bpy)32+‐doped silica nanoparticles (Ru‐DSNPs) as ECL signal‐producing compound. The sensor was fabricated by immobilizing a hairpin structure DNA probe labeled with Ru‐DSNPs onto a gold electrode and formimg the stem‐loop structure. This sensor generated a strong ECL. After hybridization with the target DNA, the ECL signal significantly decreased. The logarithm of ECL intensity decreased linearly with the logarithm of target DNA concentration in the range from 2.0×10−13 to 2.0×10−9 mol/L with detection limit was 5.0×10−14 mol/L (S/N=3).
Effect of copper ion on adsorption of chlorinated phenols and 1-naphthylamine to surface-modified carbon nanotubes
Authors: Wang Fang , Zhu Dongqiang , Chen Wei 
Published: October 2011

Abstract
Understanding the adsorptive interactions between organic contaminants and carbon nanotubes (CNTs) is critical to both environmental applications and risk management of CNTs. The objective of the present study was to understand how transitional metal ions with strong complexing capabilities might affect the adsorption of hydroxyl- and amino-substituted aromatics to surface O-functionality-rich single-walled CNTs (O-SWNT) and N-functionality-rich single-walled CNTs (N-SWNT). Adsorption of 2,4-dichlorophenol, pentachlorophenol, and 1-naphthylamine to O-SWNT and N-SWNT can be significantly enhanced in the presence of Cu(II) (50 mg/L), whereas adsorption of 1,2-dichlorobenzene is essentially unaffected. The most likely mechanism for the Cu-enhanced adsorption is that Cu(II) serves as a bridging agent between organic solutes and the functional groups on CNT surfaces. For the adsorption of 1-naphthylamine to N-SWNT, an additional mechanism might be possible; that is, the complexation of Cu(II) with the N-functional groups of N-SWNT can change these groups from strong Lewis bases to Lewis acids and thereby significantly enhance adsorption via the mechanism of Lewis acid–base interactions. In addition, adsorption of Cu(II) can be significantly enhanced by the adsorption of organic cosolutes. Environ. Toxicol. Chem. 2012;31:100–107. © 2011 SETAC
Altered brain activity during emotional empathy in somatoform disorder
Authors: de Greck Moritz , Scheidt Lisa , Bölter Annette F. , Frommer Jörg , Ulrich Cornelia , Stockum Eva , Enzi Björn , Tempelmann Claus , Hoffmann Thilo , Han Shihui , Northoff Georg 
Published: October 2011

AbstractSomatoform disorder patients suffer from impaired emotion recognition and other emotional deficits. Emotional empathy refers to the understanding and sharing of emotions of others in social contexts. It is likely that the emotional deficits of somatoform disorder patients are linked to disturbed empathic abilities; however, little is known so far about empathic deficits of somatoform patients and the underlying neural mechanisms. We used fMRI and an empathy paradigm to investigate 20 somatoform disorder patients and 20 healthy controls. The empathy paradigm contained facial pictures expressing anger, joy, disgust, and a neutral emotional state; a control condition contained unrecognizable stimuli. In addition, questionnaires testing for somatization, alexithymia, depression, empathy, and emotion recognition were applied. Behavioral results confirmed impaired emotion recognition in somatoform disorder and indicated a rather distinct pattern of empathic deficits of somatoform patients with specific difficulties in “empathic distress.” In addition, somatoform patients revealed brain areas with diminished activity in the contrasts “all emotions”–“control,” “anger”–“control,” and “joy”–“control,” whereas we did not find brain areas with altered activity in the contrasts “disgust”–“control” and “neutral”–“control.” Significant clusters with less activity in somatoform patients included the bilateral parahippocampal gyrus, the left amygdala, the left postcentral gyrus, the left superior temporal gyrus, the left posterior insula, and the bilateral cerebellum. These findings indicate that disturbed emotional empathy of somatoform disorder patients is linked to impaired emotion recognition and abnormal activity of brain regions responsible for emotional evaluation, emotional memory, and emotion generation. Hum Brain Mapp, 2012. © 2011 Wiley Periodicals, Inc.
Expertise modulates the neural basis of context dependent recognition of objects and their relations
Authors: Bilalić Merim , Turella Luca , Campitelli Guillermo , Erb Michael , Grodd Wolfgang 
Published: October 2011

AbstractRecognition of objects and their relations is necessary for orienting in real life. We examined cognitive processes related to recognition of objects, their relations, and the patterns they form by using the game of chess. Chess enables us to compare experts with novices and thus gain insight in the nature of development of recognition skills. Eye movement recordings showed that experts were generally faster than novices on a task that required enumeration of relations between chess objects because their extensive knowledge enabled them to immediately focus on the objects of interest. The advantage was less pronounced on random positions where the location of chess objects, and thus typical relations between them, was randomized. Neuroimaging data related experts' superior performance to the areas along the dorsal stream—bilateral posterior temporal areas and left inferior parietal lobe were related to recognition of object and their functions. The bilateral collateral sulci, together with bilateral retrosplenial cortex, were also more sensitive to normal than random positions among experts indicating their involvement in pattern recognition. The pattern of activations suggests experts engage the same regions as novices, but also that they employ novel additional regions. Expert processing, as the final stage of development, is qualitatively different than novice processing, which can be viewed as the starting stage. Since we are all experts in real life and dealing with meaningful stimuli in typical contexts, our results underline the importance of expert‐like cognitive processing on generalization of laboratory results to everyday life. Hum Brain Mapp, 2012. © 2011 Wiley Periodicals, Inc.
The presence of a second rat has only subtle effects on the location‐specific firing of hippocampal place cells
Authors: Zynyuk Larysa , Huxter John , Muller Robert U. , Fox Steven E. 
Published: October 2011

AbstractWe compared the spatial firing properties of hippocampal place cells as a hungry rat foraged for randomly scattered food pellets in a familiar environment while it was by itself and while it shared the arena with a second rat that also was trained in the same task. Our goal was to determine if the hippocampal mapping system remained functional in the presence of the second rat, despite a strong initial tendency of the two animals to stay close together and despite the increased complexity of the sensory surroundings. We found that almost all place cell firing fields were only marginally changed by introducing the second rat. In particular, there was no evidence of the remapping characteristic of place cells in a sufficiently different novel environment. Instead, firing fields became somewhat less well organized and slightly weaker in the presence of the second rat. These second order changes were found to be distance dependent; the degradation of firing properties was maximal when the two rats were near each other. We conclude that signals in the hippocampal mapping system are affected to a small enough extent that accurate navigational is still possible when the environment is enriched in this realistic fashion. © 2011 Wiley Periodicals, Inc.
Variability of in‐stream and riparian storage in a beaded arctic stream
Authors: Merck M. F. , Neilson B. T. , Cory R. M. , Kling G. W. 
Published: October 2011

AbstractThe extent and variability of water storage and residence times throughout the open water season in beaded arctic streams are poorly understood. Data collected in Imnavait Creek, a beaded stream located north of the Brooks Range in Alaska, were used to better understand the effects of in‐pool and riparian storage on heat and mass movement through beaded streams. Temperature data of high spatial resolution within the pools and surrounding sediments were used with volumetric discharge and electrical conductivity to identify storage areas within the pools, banks, and other marshy areas within the riparian zone, including subsurface flow paths that connect the pools. These subsurface flows were found to alter water conductivity and the character of dissolved organic matter (DOM) in short reaches (10 s of m) while influencing the chemistry of downstream pools. During low flow periods, persistent stratification occurred within the pools due to absorption of solar radiation by DOM coupled with permafrost below and low wind stress at the pool surface. Additionally, one of the shallow pools (<0.5 m depth) remained stratified during higher flow periods and lower radiation inputs due to dense subsurface flows entering the bottom of the pools. This consistent separation of surface and bottom water masses in each pool will increase the travel times through this and similar arctic watersheds, and therefore will affect the evolution of water chemistry and material export. Copyright © 2011 John Wiley & Sons, Ltd.
Changing freeze‐thaw seasons in northern high latitudes and associated influences on evapotranspiration
Authors: Zhang Ke , Kimball John S. , Kim Youngwook , McDonald Kyle C. 
Published: October 2011

AbstractSeasonal frozen states in the northern terrestrial cryosphere limit vegetation photosynthetic activities and evapotranspiration (ET) through cold temperature constraints to biological processes and chemical unavailability of water as a result of being frozen. Seasonal transitions of the landscape between predominantly frozen and thawed conditions are analogous to a biospheric and hydrological on/off switch, with marked differences in ET, vegetation productivity and other biological activity between largely dormant winter and active summer conditions. We investigated changes in freeze–thaw (FT) seasons and ET from 1983 to 2006 and their connections in the northern cryosphere by analyzing independent satellite remote sensing derived FT and ET records. Our findings show that the northern cryosphere (≥ 40°N) has experienced advancing (−2.5 days/decade; P = 0.005) and lengthening (3.5 days/decade; P = 0.007) non‐frozen season trends over the 24‐year period, coinciding with an upward trend (6.4 mm/year/decade; P = 0.014) in regional mean annual ET over the same period. Regional average timing of spring primary thaw and the annual non‐frozen period are highly correlated with regional annual ET (|r| ≥ 0.75; P < 0.001), with corresponding impacts to annual ET of approximately 0.6 and 0.5% per day, respectively. The impact of primary fall freeze timing on ET is relatively minor compared with primary spring thaw timing. Earlier onset of the non‐frozen season generally promotes annual ET in colder areas but appears to suppress summer ET by increasing drought stress in the southernmost parts of the domain where water supply is the leading constraint to ET. The cumulative effect of future freeze‐thaw changes on ET in the region will largely depend on future changes of large‐scale atmosphere circulations and rates of vegetation disturbance and adaptation to continued warming. Copyright © 2011 John Wiley & Sons, Ltd.
Exploring cell compatibility of a fibronectin‐functionalized physically crosslinked poly(vinyl alcohol) hydrogel
Authors: Millon Leonardo E. , Padavan Donna T. , Hamilton Amanda M. , Boughner Derek R. , Wan Wankei 
Published: October 2011

AbstractPhysically crosslinked poly(vinyl alcohol) (PVA) hydrogels prepared using a low‐temperature thermally cycled process have tunable mechanical properties that fall within the range of soft tissues, including cardiovascular tissue. An approach to render it hemocompatible is by endothelization, but its hydrophilic nature is not conducive to cell adhesion and spreading. We investigated the functionalization reaction of this class of PVA hydrogel with fibronectin (FN) for adhesion and spreading of primary porcine radial artery cells and vascular endothelial cells. These are cells relevant to small‐diameter vascular graft development. FN functionalization was achieved using a multistep reaction, but the activation step involving carbonyl diimidazole normally required for chemically crosslinked PVA was found to be unnecessary. The reaction resulted in an increase in the elastic modulus of the PVA hydrogel but is still well within the range of cardiovascular tissue. Confocal microscopy confirmed the adhesion and spreading of both cell types on the PVA–FN surfaces, whereas cells failed to adhere to the PVA control. This is a first step toward an alternative for the realization of a synthetic replacement small‐diameter vascular graft. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2012.
Teriparatide increases bone mineral density in a man with osteoporosis pseudoglioma
Authors: Arantes Henrique Pierotti , Barros Elizabete Ribeiro , Kunii Ilda , Bilezikian John P , Lazaretti-Castro Marise 
Published: October 2011

Abstract
Osteoporosis Pseudoglioma (OPPG) is characterized by severe juvenile-onset osteoporosis and ocular abnormalities. It is caused by one of several inactivating mutations in LRP5, a gene importantly involved in bone formation. The objective of this study was to evaluate the efficacy of teriparatide in a young man with OPPG. The subject of this case report is a 19-year-old man with congenital blindness and low trauma fractures because of OPPG. A 2-year course of teriparatide, 20 µg/day, was initiated after a 6-year course of intravenous pamidronate infusions, the latter 3 years of which had minimal effects on bone mineral density (BMD). Measurements in serum were made of C-terminal telopeptide of type I collagen (CTX), N-terminal propeptide of type I collagen (P1NP), total and ionized calcium, phosphate, uric acid, complete blood count, and renal and liver function tests. Urinary calcium/creatinine ratio was determined. BMD was measured by DXA yearly. BMD increased by 9.7% in lumbar spine and 10.2% in right femur hip. CTX rose early, peaking in month 3, followed by an increase in P1NP, peaking in month 9. Both indices returned to baseline by month 24. The increase in CTX followed by P1NP is an unusual time course when teriparatide is used to treat osteoporosis but may be typical of low bone turnover states. There were no adverse events. In a patient with OPPG, teriparatide markedly increased BMD in the lumbar spine and femur hip. © 2011 American Society for Bone and Mineral Research
An efficient one‐pot synthesis of a new heterocyclic system with high‐fluorescent properties
Authors: Rahimizadeh Mohammad , Pordel Mehdi , Ranaei Mahsa , Bakavoli Mehdi 
Published: October 2011

AbstractNucleophilic substitution of hydrogen in nitro derivative of imidazo[1,2‐a]pyridine has been used as a key step in the one‐pot synthesis of a new highly fluorescent heterocyclic system pyrido [1″,2″:1′,2′]imidazo[4′,5′:5,6]pyrido[2,3‐b]indole. J. Heterocyclic Chem., (2012).