bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spatiotemporal dynamics of processing nonsymbolic number: An event‐related potential source localization study
Authors: Hyde Daniel C. , Spelke Elizabeth S. 
Published: August 2011

AbstractCoordinated studies with adults, infants, and nonhuman animals provide evidence for two distinct systems of nonverbal number representation. The “parallel individuation” (PI) system selects and retains information about one to three individual entities and the “numerical magnitude” system establishes representations of the approximate cardinal value of a group. Recent event‐related potential (ERP) work has demonstrated that these systems reliably evoke functionally and temporally distinct patterns of brain response that correspond to established behavioral signatures. However, relatively little is known about the neural generators of these ERP signatures. To address this question, we targeted known ERP signatures of these systems, by contrasting processing of small versus large nonsymbolic numbers, and used a source localization algorithm (LORETA) to identify their cortical origins. Early processing of small numbers, showing the signature effects of PI on the N1 (∼150 ms), was localized primarily to extrastriate visual regions. In contrast, qualitatively and temporally distinct processing of large numbers, showing the signatures of approximate number representation on the mid‐latency P2p (∼200–250 ms), was localized primarily to right intraparietal regions. In comparison, mid‐latency small number processing was localized to the right temporal–parietal junction and left‐lateralized intraparietal regions. These results add spatial information to the emerging ERP literature documenting the process by which we represent number. Furthermore, these results substantiate recent claims that early attentional processes determine whether a collection of objects will be represented through PI or as an approximate numerical magnitude by providing evidence that downstream processing diverges to distinct cortical regions. Hum Brain Mapp 33:2189–2203, 2012. © 2011 Wiley Periodicals, Inc.
Unbiased comparison of sample size estimates from longitudinal structural measures in ADNI
Authors: Holland Dominic , McEvoy Linda K. , Dale Anders M. ,   the Alzheimer's Disease Neuroimaging Initiative
Published: August 2011

AbstractStructural changes in neuroanatomical subregions can be measured using serial magnetic resonance imaging scans, and provide powerful biomarkers for detecting and monitoring Alzheimer's disease. The Alzheimer's Disease Neuroimaging Initiative (ADNI) has made a large database of longitudinal scans available, with one of its primary goals being to explore the utility of structural change measures for assessing treatment effects in clinical trials of putative disease‐modifying therapies. Several ADNI‐funded research laboratories have calculated such measures from the ADNI database and made their results publicly available. Here, using sample size estimates, we present a comparative analysis of the overall results that come from the application of each laboratory's extensive processing stream to the ADNI database. Obtaining accurate measures of change requires correcting for potential bias due to the measurement methods themselves; and obtaining realistic sample size estimates for treatment response, based on longitudinal imaging measures from natural history studies such as ADNI, requires calibrating measured change in patient cohorts with respect to longitudinal anatomical changes inherent to normal aging. We present results showing that significant longitudinal change is present in healthy control subjects who test negative for amyloid‐β pathology. Therefore, sample size estimates as commonly reported from power calculations based on total structural change in patients, rather than change in patients relative to change in healthy controls, are likely to be unrealistically low for treatments targeting amyloid‐related pathology. Of all the measures publicly available in ADNI, thinning of the entorhinal cortex quantified with the Quarc methodology provides the most powerful change biomarker. Hum Brain Mapp, 2012. © 2011 Wiley Periodicals, Inc.
N‐heterocyclic carbenes. IV.1synthesis of symmetrical and unsymmetrical imidazolium salts with abietane moiety
Authors: Glushkov V. A. , Arapov K. A. , Kotelev M. S. , Rudowsky K. S. , Suponitsky K. Yu. , Gorbunov A. A. , Maiorova O. A. , Slepukhin P. A. 
Published: August 2011

AbstractMethyl 12‐chloromethyl‐dehydroabie‐tate reacts with 1‐benzyl‐ and 1‐arylimidazoles to give unsymmetrically substituted imidazolium chlorides (1a–i), with abietane moiety. Starting from methyl 12‐aminodehydroabietate, symmetrically substituted diterpene‐based salts of imidazolinium (4) and imidazolium (5) were synthesized. Anion exchange afforded corresponding (1e·BF4) and (1e·PF6). The new compounds were tested as ligands for a Pd‐catalyzed Suzuki‐Miyaura reaction. The molecular structure of (1e) is reported. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 23:5–15, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.20745
Synthesis of mono‐ and bisorganophosphorus substituted amides of unsaturated carboxylic acids with PCHNC(O) and antioxidant fragments
Authors: Prishchenko Andrey A. , Livantsov Mikhail V. , Novikova Olga P. , Livantsova Ludmila I. , Petrosyan Valery S. 
Published: August 2011

AbstractThe convenient methods for the synthesis of new mono‐ and bisorganophosphorus substituted amides of unsaturated carboxylic acids with PCHNC(O) and antioxidant fragments, starting from Arbuzov reaction of the highly reactive adducts of corresponding imines and acyl chlorides with trimethylsilyl phosphites are proposed. Some properties of the new synthesized mono‐ and bisorganophosphorus substituted amides are presented. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 23:27–31, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/.20748
The firing rate of hippocampal CA1 place cells is modulated with a circadian period
Authors: Munn Robert G.K. , Bilkey David K. 
Published: August 2011

AbstractThe accurate recall of an event is usually dependent on a memory trace that encodes three pieces of information; what happened, when the event happened, and where. The established phenomenology of hippocampal CA1 pyramidal neurons could reflect mechanisms via which some of this information (where and what) is encoded; but so far there has been little evidence for a mechanism by which these cells might represent “when.” It was therefore of interest to examine the activity of CA1 neurons over a substantial temporal duration. Forty‐eight CA1 neurons were recorded once an hour during long (24–48 h) exposures to a single, stable environment where minimal time‐of‐day cues were available. Only data from the first 25 h of recording was analyzed quantitatively. We found that the mean ensemble firing rate of these cells changed predictably such that it was closely correlated (r = 0.707) to a reference sine wave with a 25‐h period and a positive peak at recording start. This relationship was not explained by changes in the animal's running speed or amount of the recording environment covered in each recording session. When data were referenced to the onset or offset of the normal light‐on period, the correlation with the sinusoid was abolished. At an individual cell level, the majority of neurons (n = 31) had significant correlations (P < 0.05) with the reference sine. We conclude that the firing rate of a large proportion of cells in area CA1 of the hippocampus are modulated over a circadian period but that this modulation is not entrained to light. Rather, entry into the environment and the associated food availability appear to be the entraining factors. We hypothesize that these neurons may be part of the putative food‐entrainable oscillator. Such a system could enable an animal to discriminate between spatial representations on a temporal dimension with reference to the time of food availability. © 2011 Wiley Periodicals, Inc.
QTc prolongation: is clozapine safe? Study of 82 cases before and after clozapine treatment
Authors: Grande Iria , Pons Alexandre , Baeza Immaculada , Torras Ángela , Bernardo Miguel 
Published: August 2011

ObjectiveThe most feared cardiological consequence of clozapine is sudden cardiac death. A potential marker of it is QTc interval (QTc) prolongation. This study aimed to determine the prevalence of QTc prolongation in patients before and after 18 weeks of clozapine treatment and to detect predictors of QTc prolongation.MethodsPatients undergoing treatment with clozapine who had been given an electrocardiogram prior to the treatment and had their electrocardiogram, serum clozapine and norclozapine levels taken on the 18th week were selected. Exclusion criteria were thioridazine, pimozide, diuretics or beta‐blocker treatment, electrolytic alteration, heart diseases and substance misuse diagnosis. Prolonged QTc was defined as >450 ms in men and >470 ms in women.ResultsNo significant differences were detected in prevalence of prolonged QTc or mean QTc before and after 18 weeks of clozapine treatment (p = 0.15, p = 0.32, respectively). Age, heart rate at 18th week and QTc prior to clozapine treatment had significant effects on QTc at follow‐up. Prolonged QTc during previous treatment and heart rate >95 beats/min at 18 weeks were found to be predictors of QTc prolongation.ConclusionNo significant differences were detected in prevalence of QTc prolongation or mean QTc among patients before and after 18 weeks on clozapine. Copyright © 2011 John Wiley & Sons, Ltd.
Supramolecular Capsules Derived from Resorcin[4]arenes by H‐Bonding and Metal Coordination: Synthesis, Characterization, and Single‐Molecule Force Spectroscopy
Authors: Schröder Tobias , Sahu Satya Narayan , Anselmetti Dario , Mattay Jochen 
Published: August 2011

AbstractSelf‐assembly by H‐bonding and by metal‐coordination of functionalized calix[4]arenes and cavitands to large supramolecular capsules is described. In addition, a new method of analyzing supramolecular recognition processes at the single molecule level is discussed. By measuring interaction forces in a hydrogen‐bonded assembly using single‐molecule force spectroscopy (SMFS), the dynamics of the self‐assembly process can be evaluated. In the future, consequent application of this new technique will influence supramolecular design principles and the use of non‐covalent interactions as construction elements in the field of nanotechnology.
Electromagnetic fields (EMFs) and adenosine receptors modulate prostaglandin E2 and cytokine release in human osteoarthritic synovial fibroblasts
Authors: Ongaro A. , Varani K. , Masieri F.F. , Pellati A. , Massari L. , Cadossi R. , Vincenzi F. , Borea P.A. , Fini M. , Caruso A. , De Mattei M. 
Published: August 2011

AbstractSynovial fibroblasts (SFs) contribute to the development of osteoarthritis (OA) by the secretion of a wide range of pro‐inflammatory mediators, including cytokines and lipid mediators of inflammation. Previous studies suggest that electromagnetic fields (EMFs) may represent a potential therapeutic approach to limit cartilage degradation and control inflammation associated to OA, and that they may act through the adenosine pathway. Therefore, we investigated whether EMFs might modulate inflammatory activities of human SFs from OA patients (OASFs) treated with interleukin‐1β (IL‐1β), and the possible involvement of adenosine receptors (ARs) in mediating EMF effects. EMF exposure induced a selective increase in A2A and A3 ARs. These increases were associated to changes in cAMP levels, indicating that ARs were functionally active also in EMF‐exposed cells. Functional data obtained in the presence of selective A2A and A3 adenosine agonists and antagonists showed that EMFs inhibit the release of prostaglandin E2 (PGE2) and the proinflammatory cytokines interleukin‐6 (IL‐6) and interleukin‐8 (IL‐8), while stimulating the release of interleukin‐10 (IL‐10), an antinflammatory cytokine. These effects seem to be mediated by the EMF‐induced upregulation of A2A and A3 ARs. No effects of EMFs or ARs have been observed on matrix degrading enzyme production. In conclusion, this study shows that EMFs display anti‐inflammatory effects in human OASFs, and that these EMF‐induced effects are in part mediated by the adenosine pathway, specifically by the A2A and A3 AR activation. Taken together, these results open new clinical perspectives to the control of inflammation associated to joint diseases. J. Cell. Physiol. 227: 2461–2469, 2012. © 2011 Wiley Periodicals, Inc.
Functional role of an islet transcription factor, INSM1/IA‐1, on pancreatic acinar cell trans‐differentiation
Authors: Zhang Tao , Saunee Nicolle A. , Breslin Mary B. , Song Kejing , Lan Michael S. 
Published: August 2011

AbstractIn this study, the functional role of INSM1 is examined with an AR42J acinar cell model for trans‐differentiation into insulin‐positive cells. Islet transcription factors (ITFs: INSM1, Pdx‐1, and NeuroD1) are over‐expressed in AR42J cells using adenoviral vectors. Addition of Ad‐INSM1 alone or the combination of three ITFs to the AR42J cells triggers cellular trans‐differentiation. Ectopic expression of INSM1 directly induces insulin, Pax6, and Nkx6.1 expression, whereas Pdx‐1 and NeuroD1 were slightly suppressed by INSM1. Addition of Pdx‐1 and NeuroD1 with INSM1 further enhances endocrine trans‐differentiation by increasing both the numbers and intensity of the insulin–positive cells with simultaneous activation of ITFs, Ngn3 and MafA. INSM1 expression alone partially inhibits dexamethasone‐induced exocrine amylase expression. The combination of the three ITFs completely inhibits amylase expression and concomitantly induces greater acinar cell trans‐differentiation into endocrine cells. Also, addition of the three ITFs promotes EGF and TGFβ receptors expression. Stimulation by the three ITFs along with the EGF/TGFβ growth factors strongly promotes insulin gene expression. The combination of the three ITFs and EGF/TGFβ growth factors with the primary cultured pancreatic acini also facilitates exocrine to endocrine cell differentiation. Taken together, both the AR42J cell line and the primary cultured mouse acinar cells support INSM1 induced acini trans‐differentiation model. J. Cell. Physiol. 227: 2470–2479, 2012. © 2011 Wiley Periodicals, Inc.
Human mesenchymal stem cells seeded on extracellular matrix‐scaffold: Viability and osteogenic potential
Authors: Penolazzi Letizia , Mazzitelli Stefania , Vecchiatini Renata , Torreggiani Elena , Lambertini Elisabetta , Johnson Scott , Badylak Stephen F. , Piva Roberta , Nastruzzi Claudio 
Published: August 2011

AbstractThe development and the optimization of novel culture systems of mesenchymal osteoprogenitors are some of the most important challenges in the field of bone tissue engineering (TE). A new combination between cells and extracellular matrix (ECM)‐scaffold, containing ECM has here been analyzed. As source for osteoprogenitors, mesenchymal stem cells obtained from human umbilical cord Wharton's Jelly (hWJMSCs), were used. As ECM‐scaffold, a powder form of isolated and purified porcine urinary bladder matrix (pUBM), was employed. The goals of the current work were: (1) the characterization of the in vitro hWJMSCs behavior, in terms of viability, proliferation, and adhesion to ECM‐scaffold; (2) the effectiveness of ECM‐scaffold to induce/modulate the osteoblastic differentiation; and (3) the proposal for a possible application of cells/ECM‐scaffold construct to the field of cell/TE. In this respect, the properties of the pUBM‐scaffold in promoting and guiding the in vitro adhesion, proliferation, and three‐dimensional colonization of hWJMSCs, without altering viability and morphological characteristics of the cells, are here described. Finally, we have also demonstrated that pUBM‐scaffolds positively affect the expression of typical osteoblastic markers in hWJMSCs. J. Cell. Physiol. 227: 857–866, 2012. © 2011 Wiley Periodicals, Inc.
Morphogenesis and molecular mechanisms involved in human kidney development
Authors: Faa Gavino , Gerosa Clara , Fanni Daniela , Monga Giudo , Zaffanello Marco , Van Eyken Peter , Fanos Vassilios 
Published: August 2011

AbstractThe development of the human kidney is a complex process that requires interactions between epithelial and mesenchymal cells, eventually leading to the coordinated growth and differentiation of multiple highly specialized stromal, vascular, and epithelial cell types. The application of molecular biology and immunocytochemistry to the study of cell types involved in renal morphogenesis is leading to a better understanding of nephrogenesis, which requires a fine balance of many factors that can be disturbed by various prenatal events in humans. The aim of this paper is to review human kidney organogenesis, with particular emphasis on the sequence of morphological events, on the immunohistochemical peculiarities of nephron progenitor populations and on the molecular pathways regulating the process of mesenchymal to epithelial transition. Kidney development can be subdivided into five steps: (i) the primary ureteric bud (UB); (ii) the cap mesenchyme; (iii) the mesenchymal–epithelial transition; (iv) glomerulogenesis and tubulogenesis; (v) the interstitial cells. Complex correlations between morphological and molecular events from the origin of the UB and its branching to the metanephric mesenchyme, ending with the maturation of nephrons, have been reported in different animals, including mammals. Marked differences, observed among different species in the origin and the duration of nephrogenesis, suggest that morphological and molecular events may be different in different animal species and mammals. Further studies must be carried out in humans to verify at the morphological, immunohistochemical, and molecular levels if the outcome in humans parallels that previously described in other species. J. Cell. Physiol. 227: 1257–1268, 2012. © 2011 Wiley Periodicals, Inc.
POVERTY REDUCTION THROUGH PROMOTING ALTERNATIVE LIVELIHOODS: IMPLICATIONS FOR MARGINAL DRYLANDS
Authors: Adhikari Bhim 
Published: August 2011

AbstractLand degradation has become a most pressing issue in drylands. Although crop and livestock production have been the dominant sources of income, there is an increasing realisation that alternative livelihood options need to be explored to ensure both environmental and economic sustainability. This paper provides a systematic review of alternative livelihood strategies currently adopted for improving livelihood conditions of dryland dwellers in different parts of the world. Although drylands encompass a vast social and geographic terrain and represent a heterogeneous socio‐economic environment, this paper has been able to document some general lessons applicable to rural drylands for diversifying livelihood opportunities and promoting rural development while minimising the pressure from intensive land‐based activities. The paper concludes with a discussion on how international development policies can move forward in the fight against land degradation and in helping achieve poverty reduction through investments in sustainable land management and alternative livelihood strategies. Copyright © 2011 John Wiley & Sons, Ltd.
Hybrid modelling and emulation of mem‐systems
Authors: Kolka Zdeněk , Biolek Dalibor , Biolková Viera 
Published: August 2011

SUMMARYThe recently published memristor emulator is based on a digital potentiometer, which is controlled by a microprocessor according to a programmed algorithm. After completing the emulator with suitable mutators, it is possible to emulate also memcapacitors and meminductors. This paper describes a novel approach to the modelling and emulation of general mem‐systems without the necessity of utilizing a digital potentiometer and additional mutators. Copyright © 2011 John Wiley & Sons, Ltd.
Stable Cellulose Nanospheres for Cellular Uptake
Authors: Liebert Tim , Kostag Marc , Wotschadlo Jana , Heinze Thomas 
Published: August 2011

AbstractPure, perfectly spherical cellulose nanoparticles with sizes of ≈80–260 nm can be prepared by dialysis starting from trimethylsilylcellulose (TMSC). The aqueous suspensions obtained are storable for several months. Subsequent covalent labeling of the cellulose nanoparticles with FITC has no influence on particle size, shape, and stability. The particles can be sterilized and suspended in biological media without structural changes. Incorporation of FITC‐labeled cellulose nanoparticles into living human fibroblasts is studied using confocal LSM. In contrast to cellulose nanocrystals, fast cellular uptake is found for the nanospheres without transfection reagents or attachment of a receptor molecule. This suggests an influence of the geometry of biocompatible nanomaterials on endocytosis.magnified image
Amylose's Recognition of Chirality in Polylactides on Formation of Inclusion Complexes in Vine‐Twining Polymerization
Authors: Kaneko Yoshiro , Ueno Koji , Yui Toshifumi , Nakahara Keisuke , Kadokawa Jun‐ichi 
Published: August 2011

AbstractAmylose selectively includes poly(L‐lactide) (PLLA) among the poly(lactide)s (PLAs) to produce an inclusion complex when the phosphorylase‐catalyzed polymerization of α‐D‐glucose 1‐phosphate is performed in the presence of PLLA, poly(D‐lactide) (PDLA), or poly(DL‐lactide) (PDLLA) (vine‐twining polymerization). This result indicates that amylose recognizes the chirality in PLAs on the formation of an inclusion complex in vine‐twining polymerization. Modeling calculations support the amylose's chiral recognition in favor of PLLA and the atomistic details of the inclusion complex which involved the preferred orientation of the constituent molecular chains with respect to their fiber axis is proposed. magnified image
A Collagen Peptide‐Based Physical Hydrogel for Cell Encapsulation
Authors: Rubert Pérez Charles M. , Panitch Alyssa , Chmielewski Jean 
Published: August 2011

AbstractCollagen peptide‐based hydrogels are prepared and characterized for application in 3D cell growth. Physical hydrogels are formed by covalently linking a collagen‐based peptide to an 8‐arm poly(ethylene glycol) star polymer. The resulting viscoelastic hydrogels have the ability to melt into a liquid‐like state near the melting temperature of the collagen triple helix and reform back into an elastic‐state at room temperature, adding a thermoresponsive feature to the material. In addition, the hydrogels possess desirable stiffness, as well as a highly cross‐linked network of pores where cells are found to reside, making the hydrogels promising scaffolds for the culture of hMSCs.magnified image
Synthesis and passivation behavior of electroless Ni–P‐CNT composite coating
Authors: Alishahi M. , Hosseini S. M. , Monirvaghefi S. M. , Saatchi A. 
Published: August 2011

AbstractCarbon nanotubes (CNTs) have high chemical stability, unique hollow nanotube structure, and are believed to be ideal materials for fabricating composites. In this study, Ni–P and Ni–P‐CNT composite coatings were fabricated by electroless plating. Scanning electron microscopy was used to characterize the coatings. The corrosion behavior of Ni–P and Ni–P‐CNT coated samples were evaluated by polarization curves and electrochemical impedance spectroscopy in 3.5 wt% NaCl and 0.1 M H2SO4 aqueous solutions at room temperature. The results indicated that incorporation of CNTs in the coating significantly increased corrosion resistance. The role of CNTs in improvement of corrosion resistance of the coating was also discussed.