bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of the neural correlates of retrieval success in tests of cued recall and recognition memory
Authors: Okada Kayoko , Vilberg Kaia L. , Rugg Michael D. 
Published: March 2011

AbstractThe neural correlates of successful retrieval on tests of word stem recall and recognition memory were compared. In the recall test, subjects viewed word stems, half of which were associated with studied items and half with unstudied items, and for each stem attempted to recall a corresponding study word. In the recognition test, old/new judgments were made on old and new words. The neural correlates of successful retrieval were identified by contrasting activity elicited by correctly endorsed test items. Old > new effects common to the two tasks were found in medial and lateral parietal and right entorhinal cortex. Common new > old effects were identified in medial and left frontal cortex, and left anterior intra‐parietal sulcus. Greater old > new effects were evident for cued recall in inferior parietal regions abutting those demonstrating common effects, whereas larger new > old effects were found for recall in left frontal cortex and the anterior cingulate. New > old effects were also found for the recall task in right lateral anterior prefrontal cortex, where they were accompanied by old > new effects during recognition. It is concluded that successful recall and recognition are associated with enhanced activity in a common set of recollection‐sensitive parietal regions, and that the greater activation in these regions during recall reflects the greater dependence of that task on recollection. Larger new > old effects during recall are interpreted as reflections of the greater opportunity for iterative retrieval attempts when retrieval cues are partial rather than copy cues. Hum Brain Mapp, 2012. © 2011 Wiley Periodicals, Inc.
Optimizing preprocessing and analysis pipelines for single‐subject fMRI. I. Standard temporal motion and physiological noise correction methods
Authors: Churchill Nathan W. , Oder Anita , Abdi Hervé , Tam Fred , Lee Wayne , Thomas Christopher , Ween Jon E. , Graham Simon J. , Strother Stephen C. 
Published: March 2011

AbstractSubject‐specific artifacts caused by head motion and physiological noise are major confounds in BOLD fMRI analyses. However, there is little consensus on the optimal choice of data preprocessing steps to minimize these effects. To evaluate the effects of various preprocessing strategies, we present a framework which comprises a combination of (1) nonparametric testing including reproducibility and prediction metrics of the data‐driven NPAIRS framework (Strother et al. [2002]: NeuroImage 15:747–771), and (2) intersubject comparison of SPM effects, using DISTATIS (a three‐way version of metric multidimensional scaling (Abdi et al. [2009]: NeuroImage 45:89–95). It is shown that the quality of brain activation maps may be significantly limited by sub‐optimal choices of data preprocessing steps (or “pipeline”) in a clinical task‐design, an fMRI adaptation of the widely used Trail‐Making Test. The relative importance of motion correction, physiological noise correction, motion parameter regression, and temporal detrending were examined for fMRI data acquired in young, healthy adults. Analysis performance and the quality of activation maps were evaluated based on Penalized Discriminant Analysis (PDA). The relative importance of different preprocessing steps was assessed by (1) a nonparametric Friedman rank test for fixed sets of preprocessing steps, applied to all subjects; and (2) evaluating pipelines chosen specifically for each subject. Results demonstrate that preprocessing choices have significant, but subject‐dependant effects, and that individually‐optimized pipelines may significantly improve the reproducibility of fMRI results over fixed pipelines. This was demonstrated by the detection of a significant interaction with motion parameter regression and physiological noise correction, even though the range of subject head motion was small across the group (≪ 1 voxel). Optimizing pipelines on an individual‐subject basis also revealed brain activation patterns either weak or absent under fixed pipelines, which has implications for the overall interpretation of fMRI data, and the relative importance of preprocessing methods. Hum Brain Mapp, 2012. © 2011 Wiley Periodicals, Inc.
β‐catenin as a potential key target for tumor suppression
Authors: Fu Yuejun , Zheng Shuhua , An Na , Athanasopoulos Takis , Popplewell Linda , Liang Aihua , Li Ke , Hu Changchen , Zhu Yajing 
Published: March 2011

Abstractβ‐catenin is a multifunctional protein identified to be pivotal in embryonic patterning, organogenesis and adult homeostasis. It plays a critical structural role in mediating cadherin junctions and is also an essential transcriptional co‐activator in the canonical Wnt pathway. Evidence has been documented that both the canonical Wnt pathway and cadherin junctions are deregulated or impaired in a plethora of human malignancies. In the light of this, there has been a recent surge in elucidating the mechanisms underlying the etiology of cancer development from the perspective of β‐catenin. Here, we focus on the emerging roles of β‐catenin in the process of tumorigenesis by discussing novel functions of old players and new proteins, mechanisms identified to mediate or interact with β‐catenin and the most recently unraveled clinical implications of β‐catenin regulatory pathways toward tumor suppression.
Cancer risk in patients with allergic rhinitis, asthma and atopic dermatitis: A nationwide cohort study in Taiwan
Authors: Hwang Chian‐Yaw , Chen Yi‐Ju , Lin Ming‐Wei , Chen Tzeng‐Ji , Chu Szu‐Ying , Chen Chih‐Chiang , Lee Ding‐Dar , Chang Yun‐Ting , Wang Wen‐Jen , Liu Han‐Nan 
Published: March 2011

AbstractIt has long been a debate that whether atopy is a risk factor or protective factor for cancer. However, no large‐scale study of different cancers in patients with atopic diseases has been conducted among Asians. Here, we conducted a nationwide study to evaluate the cancer risk in patients with allergic rhinitis (AR), asthma and atopic dermatitis (AD). Drawing on Taiwan's National Health Insurance Research Database, 225,315 patients with AR, 107,601 patients with asthma and 34,263 patients with AD without prior cancers were identified in the period from 1996 to 2008. The standard incidence ratio (SIR) of each cancer was calculated. Although the overall cancer risks in patients with atopic symptoms were not increased, the risks were slightly elevated in female patients with AR or asthma (SIR: 1.13 and 1.08, AR and asthma, respectively) and slightly decreased in males patients with AR. Those aged 20–39 years‐old possessed the highest risk. A higher risk of developing brain cancer was found in patients with atopic diseases, and patient with AR or asthma also had an elevated risk of developing cancer of kidney and urinary bladder. In contrast, the risk of nonmelanoma skin cancer was lower in patients with AR and asthma. Compared to patients with only one atopic disease, those with more than one atopic disease had lower cancer risks. Our data suggests that the association between atopy and cancer is site‐specific.
Growth‐inhibitory and chemosensitizing effects of the glutathione‐S‐transferase‐π‐activated nitric oxide donor PABA/NO in malignant gliomas
Authors: Kogias Evangelos , Osterberg Nadja , Baumer Brunhilde , Psarras Nikolaos , Koentges Christoph , Papazoglou Anna , Saavedra Joseph E. , Keefer Larry K. , Weyerbrock Astrid 
Published: March 2011

AbstractGlutathione‐S‐transferases (GSTs) are upregulated in malignant gliomas and contribute to their chemoresistance. The nitric oxide (NO) donor PABA/NO (O2‐{2,4‐dinitro‐5‐[4‐(N‐methylamino)benzoyloxy]phenyl} 1‐(N,N‐dimethylamino)diazen‐1‐ium‐1,2‐diolate) generates NO upon selective enzymatic activation by GST‐π‐inducing selective biological effects in tumors. Tumor cell killing and chemosensitization were observed in a variety of tumors after exposure to GST‐activated NO donor drugs. In our project, cytotoxic and chemosensitizing effects of PABA/NO in combination with carboplatin (CPT) and temozolomide (TMZ) were studied in human U87 glioma cells in vitro and in vivo. U87 glioma cells were exposed to PABA/NO alone or in combination with CPT or TMZ for 24 hr. Cell viability was assessed by 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay after 24‐hr incubation and 48 hr after drug removal. The antiproliferative effect of PABA/NO was assessed in an intracranial U87 glioma nude rat model comparing subcutaneous administration and intratumoral delivery by convection‐enhanced delivery. PABA/NO monotherapy showed a strong dose‐dependent growth‐inhibitory effect in U87 glioma cells in vitro, and a strong synergistic effect was observed after concomitant treatment with TMZ, but not with CPT. Systemic and intratumoral PABA/NO administration significantly reduced cell proliferation, but this did not result in prolonged survival in nude rats with intracranial U87 gliomas. PABA/NO has potent antiproliferative effects, sensitizes U87 glioma cells to TMZ in vitro and shows some in vivo efficacy. Further studies are still required to consolidate the role of NO donor therapy in glioma treatment.
Expression of microRNA 210 associates with poor survival and age of tumor onset of soft‐tissue sarcoma patients
Authors: Greither T. , Würl P. , Grochola L. , Bond G. , Bache M. , Kappler M. , Lautenschläger C. , Holzhausen H.‐J. , Wach S. , Eckert A.W. , Taubert H. 
Published: March 2011

AbstractExpression of microRNAs can affect age of tumor onset and prognosis of cancer patients. However, nothing is known about the effects of microRNAs on altered age of cancer onset and disease‐specific survival of soft‐tissue sarcoma (STS) patients. The levels of miR‐210, also known as hypoxia‐regulated microRNA, were analyzed by quantitative real‐time (RT)‐PCR in the tumors of 78 STS patients. The patients were stratified according to their microRNA levels with low, intermediate and high expression levels and the association of microRNA expression and patients' survival was analyzed using multivariate Cox's regression hazard analyses. A significant correlation between an intermediate miR‐210 expression and disease‐specific death of STS patients [relative risk (RR) = 3.19; p = 0.018] was observed compared with patients with high expression levels in their tumors. Interestingly, the association between an intermediate expression of miR‐210 and a poor prognosis was only significant in female STS patients (RR = 11.28; p = 0.010), but not observed in male individuals. Furthermore, the expression of miR‐210 showed a significant association with the age of tumor onset in a gender‐specific manner. Specifically, male patients with an intermediate expression of miR‐210 associated with a 9.6‐year later age of tumor onset (p = 0.017) compared with males with a low expression of miR‐210 in their tumors. However, no significant differences in the female patients were observed. This study provides the first evidence of a correlation of expression levels of a single microRNA (miR‐210) with the prognosis and age of tumor onset in a gender‐specific manner in STS patients.
A new hybrid algorithm for finding the lowest minima of potential surfaces: Approach and application to peptides
Authors: Goldstein Moshe , Fredj Erick , Gerber R. Benny 
Published: March 2011

AbstractA new algorithm is presented for finding the global minimum, and other low‐lying minima, of a potential energy surface (PES) of biological molecules. The algorithm synergetically combines three well‐known global optimization methods: the diffusion equation method (DEM), which involves smoothing the PES; a simulated annealing (SA) algorithm; and evolutionary programming (EP), whose population‐oriented approach allows for a parallel search over different regions of the PES. Tests on five peptides having between 6 and 9 residues show that the code implementing the new combined algorithm is efficient and is found to outperform the constituent methods, DEM and SA. Results of the algorithm, in the gas phase and with the GBSA implicit solvent model, are compared with crystallographic data for the test peptides; good accord is found in all cases. Also, for all but one of the examples, our hybrid algorithm finds a minimum deeper than those obtained by a very extensive scan. TINKERs implementation of the OPLS‐AA force field is employed for the structure prediction. The results show that the new algorithm is a powerful structure predictor, when a reliable potential function is available. Our implementation of the algorithm is time‐efficient, and requires only modest computational resources. Work is underway on applications of the new algorithm to structural prediction of proteins and other biological macro‐molecules. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011
Enantioselective organocatalytic diels–Alder reactions: A density functional theory and kinetic isotope effects study
Authors: Omar Nasr Y.M. , Rahman Noorsaadah A. , Zain Sharifuddin MD 
Published: March 2011

AbstractThe mechanism and enantioselectivity of the organocatalytic Diels–Alder reaction were computationally investigated by density functional theory at the B3LYP/6‐31G(d) level of theory. The uncatalyzed Diels–Alder reaction was also studied to explore the effect of the organocatalyst on this reaction in terms of energetics, selectivity, and mechanism. The catalyzed reaction showed improved endo/exo selectivity, and the free energy of activation was significantly lowered in the presence of the catalyst. Both uncatalyzed and catalyzed reactions exhibited concerted asynchronous reaction mechanism with the degree of asynchronicity being more evident in the presence of the catalyst. The Corey's experimentally derived predictive selection rules for the outcome of the organocatalytic Diels–Alder reaction were also theoretically analyzed, and an excellent agreement was found between experiment and theory. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011
Electronic and chelation effects on the unusual C2‐methylation of N‐(para‐substituted)phenylaziridines with lithium organocuprates
Authors: Kim Jongtaek , Yoo Eunjung , Chang Sukbok , Lee Yoon Sup 
Published: March 2011

AbstractDensity functional theory calculations with the B3LYP functional were performed for the title ring‐opening reaction to understand the intrinsic activating and directing effects of the N‐substituents, as well as the electron donating effect of the para‐substituted (Y = Cl, H, Me) phenyl group at the more hindered benzylic C2 atom. The N‐tosyl group (i.e., N‐Tos) or the N‐(2‐pyridyl)sulfonyl group (i.e., N‐Py) was introduced to activate the ring nitrogen atom (N1) and the para‐substituted (Y = Cl, H, Me) phenyl group for the activation of the C2 atom. Conformational searches and geometry optimizations were performed for the N‐(para‐substituted)phenylaziridines (1∼6). Calculations indicate that the aziridine 6 (i.e., Py/Me) has the most elongated C2N1 bond intrinsically due to the electronic activating effects, implying the aziridine 6 to be the most potent candidate for the more‐hindered C2 opening. Transition states (TSs) were investigated for the prospective ring‐opening paths (I∼IV), considering the types of intermolecular push–pull interactions between the N‐activated phenylaziridines and the cuprate. The N‐Py group provides an unique C2‐favored TS along the path IV, which the N‐Tos group cannot afford, due to the less charge transfer from the nucleophilic CH of the cuprate into the electrophilic C2 atom. Furthermore, the e‐donating effect of the para‐substituents (Y = Cl, H, Me) enhances the C2 opening for the path IV. This study enables us to understand the unusual ring‐opening phenomena in terms of electronic and directing effects and hence may serve as a tool to design substrates for highly regioselective ring openings. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011
Regeneration of amphioxus oral cirri and its skeletal rods: implications for the origin of the vertebrate skeleton
Authors: Kaneto Satoshi , Wada Hiroshi 
Published: March 2011

AbstractThe oral cirri of amphioxus function as the first filter during feeding by eliminating unwanted large or noxious particulates. In this study, we were able to regenerate cirri following artificial amputation. This is the first firm observation of regeneration in amphioxus. Using this regeneration system, we studied skeletogenesis of the cellular skeleton of amphioxus oral cirri. During regeneration, the skeletal cells showed expression of fibrillar collagen and SoxE genes. These observations suggest that an evolutionarily conserved genetic regulatory system is involved in amphioxus cirrus and vertebrate cartilage skeletogenesis. In addition, Runx and SPARC/osteonectin expression were observed in regenerating cirral skeletal cells, indicating that cirral skeletogenesis is similar to vertebrate osteogenesis. We propose that the common ancestors of chordates possessed a genetic regulatory system that was the prototype of chondrogenesis and osteogenesis in vertebrates. Genome duplications caused divergence of this genetic regulatory system resulting in the emergence of cartilage and mineralized bone. The development of the vertebrate skeleton is an example of the functional segregation and subsequent recruitment of unique genetic materials that may account for the evolutionary diversification of novel cell types. J. Exp. Zool. (Mol. Dev. Evol.) 316:409–417, 2011. © 2011 Wiley‐Liss, Inc.
Pyrazoles and pyrazolo[4,3‐e]pyrrolo[1,2‐a]pyrazines II
Authors: Farghaly Abdel‐Rahman , El‐Kashef Hussein 
Published: March 2011

AbstractSynthesis of the title compounds was achieved using the anils 2a, 2b, 2c, 2d, 2e and 5a, 5b, 5c derived from the 4‐aminopyrazole 1 as starting materials. These compounds were allowed to react with mercaptoacetic acid in boiling dry benzene to afford the corresponding thiazolidinones and spiro‐thiazolidinones 3a, 3b, 3c, 3d, 3e and 6a, 6b, 6c, respectively. Pictet—Spengler reaction of the 4‐aminopyrazole hydrochloride 7 with aromatic aldehydes and cyclic ketones resulted in the formation of new pyrazolo[4,3‐e]pyrrolo[1,2‐a]pyrazines 8a, 8b, 8c, 8d, 8e and 9a, 9b, respectively. Other derivatives of pyrazolo pyrrolopyrazines 10 and 11 were obtained via the reaction of the amino derivative 1 with 1,1′‐carbonyldiimidazol and CS2, respectively. J. Heterocyclic Chem., (2011).
Microstructure of dental hard tissues in fossil and recent xenarthrans (Mammalia: Folivora and Cingulata)
Authors: Kalthoff Daniela C. 
Published: March 2011

AbstractA striking difference between xenarthrans and other mammals is the complete loss of tooth enamel in all members but the earliest armadillos. However, sloth and armadillo teeth show structured wear facets, which in all other mammals are formed by tooth enamel. How is that possible? Here, I report about an analysis of fossil and recent xenarthran dental hard tissue microstructure. It shows that osteodentine is not exclusive to fossil Cingulata, but also occurs in some recent taxa. Furthermore, I found profound modifications of orthodentine architecture in comparison to other mammals. Remarkable features are (a) a larger proportion of the highly mineralized, collagen‐free peritubular dentine, and (b) a modified architecture of the odontoblastic process with frequent interconnections between the extensions and unusually intensive branching of the extensions forming a complex meshwork, penetrating the intertubular dentine matrix. The orthodentine microstructural build‐up is unique in Folivora and Cingulata. J. Morphol., 2011. © 2011 Wiley‐Liss, Inc.
Dissection of dispersed off‐resonant femtosecond degenerate four‐wave mixing of O2
Authors: Knopp G. , Radi P. P. , Sych Y. , Gerber T. 
Published: March 2011

AbstractSimultaneous time and frequency detection in off‐resonant femtosecond degenerate four‐wave mixing (fs‐DFWM) experiments displays spectral features that are covered in standard, nondispersed, frequency‐integrated measurements. The application of laser fields with finite bandwidths, narrower than or comparable to the rotational Raman bands, affects the observed coherent signals. Information available from such experiments is split between the time and frequency domains and an improved measurement necessitates a combined detection. Rotational recurrences of oxygen (O2), measured by dispersed fs‐DFWM at room temperature, exhibit spectral characteristics, using 800‐nm laser pulses with ∼100 fs duration. Analysis of the detected signals in both dimensions incorporating temporal and spectral trends can assist in the extraction and interpretation of chemicophysical quantities from the experiment. The dispersed recurrent signals are in accordance with simulations. Copyright © 2011 John Wiley & Sons, Ltd.
Phase‐locking of two independent degenerate coherent anti‐Stokes Raman scattering processes: concept, proposed all‐optical implementation, and potential applications
Authors: Zhang Qun 
Published: March 2011

AbstractA novel approach toward phase‐locking of two independently produced yet energetically degenerate coherent anti‐Stokes Raman scattering (CARS) processes is put forward. The proposed all‐optical implementation involves a modified Mach–Zehnder interferometer, which is utilized to transfer phase coherence from three totally uncorrelated laser beams into two degenerate CARS beams that are produced in two distinct Raman active samples. Such a CARS interferometer based on coherent phase transport allows explicit measurement and control of phase differences between the two phase‐locked degenerate CARS processes, and hence may find applications in pertinent research fields such as CARS spectroscopy (tomography) as well as quantum information processing and transfer. Copyright © 2011 John Wiley & Sons, Ltd.
Low‐wavelength emission of Nd‐doped lasers
Authors: Balembois F. , Castaing M. , Hérault E. , Georges P. 
Published: March 2011

AbstractThis paper gives an overview of the results obtained with diode‐pumped Neodymium‐doped crystals operating below 900 nm. Operation at such low wavelengths requires considering the strong thermal population of the lower level of the laser transition. Based on a theoretical study and simulations, the paper presents the challenges related to the design of these three‐level lasers. Experimental results are given with Nd:YAG and Nd:vanadate crystals. It is explained how to deal with the line competition with emission at 946 nm or 912 nm. Finally, intracavity second‐harmonic generation is presented. The output powers reach a few hundred mW at wavelengths below 450 nm. Hence, the paper demonstrates the potential of Nd‐doped diode‐pumped solid‐state lasers for applications in the blue range, in replacement of gas lasers such as helium‐cadmium lasers.
Film‐forming properties of castor oil–polyol ester blends in elastohydrodynamic conditions
Authors: Bantchev Grigor B. , Biresaw Girma 
Published: March 2011

ABSTRACTThe viscosity and elastohydrodynamic (EHD) film thickness properties of binary blends of castor oil with polyol esters were determined experimentally. Predicted blend viscosities were calculated from the viscosities of the pure blend components. Measured viscosity values were closer to the values predicted using the Lederer model than the Arrhenius model. EHD film thickness data were mostly in agreement with the predictions of the Hamrock–Dowson model. Observed deviations of EHD film thickness were attributed to boundary film formation and thermal effects. Calculated effective pressure–viscosity coefficients, α, displayed a complex relationship with blend viscosity. At 40°C, the addition of 10% polyol esters resulted in a 12–17% drop in α of castor oil. Higher concentrations of polyol esters resulted in an increase of α. At 70 and 100°C, α displayed an almost linear dependence on blend composition. Copyright © 2011 John Wiley & Sons, Ltd.