bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Anthracene Based Photoswitchable Dioxo‐Tetraaza Ligand Selective for CuII and Capable of Photochemical pKa Modulation
Authors: Dacarro Giacomo , Ricci Paola , Sacchi Donatella , Taglietti Angelo 
Published: January 2011

AbstractTwo anthracene fragments were added to a linear dioxotetramine ligand in order to exploit a [4πs+4πs] photocycloaddition reaction and obtain a photoswitchable selective receptor for CuII, whose cavity (and binding abilities) can be closed on command. Moreover, it was demonstrated that this new ligand, N,N′‐bis{2‐[(anthracen‐9‐ylmethyl)amino]ethyl}malonamide (LH2), can also be used for the photoinduced release of protons in aqueous solution, as a result of photoinduced pKa modulation.
A New Triazine‐Based Tricompartmental Ligand for Stepwise Assembly of Mononuclear, Dinuclear, and 1D‐Polymeric Heptacoordinate Manganese(II)/Azido Complexes
Authors: Das Animesh , Demeshko Serhiy , Dechert Sebastian , Meyer Franc 
Published: January 2011

AbstractA new ligand 2,4,6‐tris[{N‐methyl‐N′‐(pyridine‐2‐yl)methylidene}hydrazino]‐1,3,5‐triazine (L) has been synthesized from cyanuric chloride in two steps. The threefold symmetric L features three potentially tridentate {N3} binding compartments. However, with MnII it binds a single metal ion using one of the triazine N atoms and two chelate arms. This {N5} set forms the equatorial plane of a distorted pentagonal‐bipyramidal metal ion environment, with a variety of ligands in axial positions. Five such MnII complexes have been isolated and characterized by X‐ray crystallography. Complex 1 features axial water and nitrato‐O ligands. In 5, the latter is replaced by dicyanamide. Two terminal azido ligands are found in 3. Depending on the ratio of L:MnII:azide, L may also adopt a bridging mode to give the dimeric species [{(H2O)MnIIL}(μ‐1,3‐N3){LMnII(NO3)}](NO3)2 (2) or a 1D coordination polymer [(LMnII)(μ‐1,3‐N3)]n(NO3)n (4). The basic {LMnII} entity undergoes little structural variation in the series of complexes, which can be viewed as structural snapshots for the assembly of a MnII/azido polymeric chain from well‐defined mononuclear building units. Magnetic coupling along the μ‐1,3‐azido linkage in the dimeric and 1D‐extended complexes is weakly antiferromagnetic; the strength of the coupling is rationalized on the basis of the Mn–N–N angles and the dihedral angle τ along the azide ligand.
Ring‐Closing Metathesis Approach to Heteroaromatic Cations: Synthesis of Benzo[a]quinolizinium Salts
Authors: Nuñez Ana , Abarca Beatriz , Cuadro Ana M. , Alvarez‐Builla Julio , Vaquero Juan J. 
Published: January 2011

AbstractBenzo[a]quinolizinium salts have been synthesized through ring‐closing metathesis reactions of 1‐butenyl‐2‐vinylisoquinolinium, 2‐butenyl‐1‐vinylisoquinolinium and 2‐styryl‐1‐vinylpyridinium salts in the presence of Grubbs andHoveyda–Grubbs catalysts. The results show that the lastapproach is the most efficient for the preparation of this heteroaromatic tricyclic system and several previously unknown derivatives have been prepared.
Diaryl Ether Formation in the Synthesis of Natural Products
Authors: Pitsinos Emmanuel N. , Vidali Veroniki P. , Couladouros Elias A. 
Published: January 2011

AbstractThe structural variety of naturally occurring diaryl ethers is illustrated and the various synthetic methods employed for the construction of diaryl ether linkages in related total syntheses are reviewed. Examples of successful applications of each method (including reaction conditions, diaryl ether substitution pattern, and, when appropriate, the size of the ring formed) are given in tabular format.
A latent variable approach to forecasting the unemployment rate
Authors: Chua Chew Lian , Lim G. C. , Tsiaplias Sarantis 
Published: January 2011

ABSTRACTA forecasting model for unemployment is constructed that exploits the time series properties of unemployment while satisfying the economic relationships specified by Okun's law and the Phillips curve. In deriving the model, we jointly consider the problem of obtaining estimates of the unobserved potential rate of unemployment consistent with Okun's law and the Phillips curve, and associating the potential rate of unemployment with actual unemployment. The empirical example shows that the model clearly outperforms alternative forecasting procedures typically used to forecast unemployment. Copyright © 2011 John Wiley & Sons, Ltd.
Lineage tracing demonstrates no evidence of cholangiocyte epithelial-to-mesenchymal transition in murine models of hepatic fibrosis
Authors: Chu Andrew S. , Diaz Rosalyn , Hui Jia-Ji , Yanger Kilangsungla , Zong Yiwei , Alpini Gianfranco , Stanger Ben Z. , Wells Rebecca G. 
Published: January 2011

Abstract

Whether or not cholangiocytes or their hepatic progenitors undergo an epithelial-to-mesenchymal transition (EMT) to become matrix-producing myofibroblasts during biliary fibrosis is a significant ongoing controversy. To assess whether EMT is active during biliary fibrosis, we used Alfp-Cre × Rosa26-YFP mice, in which the epithelial cells of the liver (hepatocytes, cholangiocytes, and their bipotential progenitors) are heritably labeled at high efficiency with yellow fluorescent protein (YFP). Primary cholangiocytes isolated from our reporter strain were able to undergo EMT

in vitro

when treated with transforming growth factor-β1 alone or in combination with tumor necrosis factor-α, as indicated by adoption of fibroblastoid morphology, intracellular relocalization of E-cadherin, and expression of α-smooth muscle actin (α-SMA). To determine whether EMT occurs

in vivo

, we induced liver fibrosis in Alfp-Cre × Rosa26-YFP mice using the bile duct ligation (BDL) (2, 4, and 8 weeks), carbon tetrachloride (CCl4) (3 weeks), and 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC; 2 and 3 weeks) models. In no case did we find evidence of colocalization of YFP with the mesenchymal markers S100A4, vimentin, α-SMA, or procollagen 1α2, although these proteins were abundant in the peribiliary regions.

Conclusion:

Hepatocytes and cholangiocytes do not undergo EMT in murine models of hepatic fibrosis. (Hepatology 2011;)
Assessing human resource practices alignment: A case study
Authors: Heneman Herbert G. , Milanowski Anthony T. 
Published: January 2011

AbstractResearch has established the link between HR practices and organizational performance, suggesting that the HR system has great strategic potential to drive organizational effectiveness. To capitalize on this potential, the organization must design and deliver HR practices that focus on necessary employee performance competencies, creating an HR system with vertical and horizontal alignment around those competencies. Doing this requires that the organization first assess how its HR practices are currently aligned and then develop ideas for improving HR practice that will be alignment enhancing. We call this diagnostic process Human Resource Alignment (HRA) assessment. We describe an HRA assessment process we developed and applied in a large public school district for the key job of teacher. The assessment was based on the district's formal teacher performance competency model used, and was conducted by a group of human resources and instructional job experts from the district. These experts rated the degree of vertical and horizontal alignment and then developed suggestions for HR practice changes that would improve alignment. After describing the process and results, we present a series of lessons learned and directions for future research. © 2011 Wiley Periodicals, Inc.
Tracing a confined groundwater flow system under the pressure of excessive groundwater use in the lower central plain, Thailand
Authors: Yamanaka Tsutomu , Shimada Jun , Tsujimura Maki , Lorphensri Oranuj , Mikita Makoto , Hagihara Atsushi , Onodera Shinichi 
Published: January 2011

AbstractExcessive groundwater pumping from deep wells in the Bangkok metropolitan area (BMA) since the 1950s has induced piezometric drawdown, land subsidence, and probably remarkable disturbance in confined groundwater flow. To trace the large‐scale groundwater flow system in the Lower Central Plain (LCP) of Thailand and to detect its disturbance, we carried out isotopic and hydro‐chemical investigations of surface/subsurface waters as well as hydrometric measurements at 98 observation wells. Isotopic compositions of the water (δD and δ18O) reflected significant seawater mixing and evaporative enrichment. The Cl/Br mass ratio suggested that halite dissolution is negligible, and spatial distributions of δ and Cl− concentration implied that saline water is mainly remnant seawater. In addition, the δ–Cl relationship indicated that the remnant seawater may have been concentrated in part by transpiration from mangrove forests during delta formation after a period of maximum transgression. The original δD of the source water was estimated by correcting for the effects of seawater mixing and evaporative enrichment using the Cl− concentration and δ18O, respectively, and its three‐dimensional distribution revealed that the water originating from precipitation over the LCP during the post‐glacial age was drawn down to a maximum depth of 240 m by groundwater pumping. At two large depressions in the east and west of the BMA, water recharged during the last glacial age and/or originating at higher elevations outside the LCP is drawn from suburban areas laterally or through underlying aquifers. In contrast, in the central BMA, groundwater within major productive aquifers is mainly replenished by downward leakage across confining layers. Copyright © 2011 John Wiley & Sons, Ltd.
Simulation of complicated and diverse water system accompanied by human intervention in the North China Plain
Authors: Nakayama Tadanobu 
Published: January 2011

AbstractThe author simulated water/heat dynamics in the North China plain (NCP) by coupling the NIES Integrated Catchment‐based Eco‐hydrology (NICE) model series with dam/canal systems in the agricultural and urban areas (NICE‐CNL). This combined model was applied to the Hai River catchment and the lower reach of the Yellow River (530 km wide × 840 km long) at a resolution of 5 km. It satisfactorily reproduced river discharge, soil moisture, evapotranspiration, groundwater level, and crop production of summer maize and winter wheat, correctly estimating—without any detailed statistical data—the amount of crop water use. The simulation showed that irrigation and industrial use of groundwater has a marked effect on the water dynamics in the NCP because the river water volume is smaller than that necessary for irrigation, industrial and, domestic water use. The model reproduced, reasonably well, the trend of groundwater degradation over the previous half century, including cone depressions occurring around bigger cities, which the author was unable to reproduce in previous research. The simulation also clarified that this water shortage is related to the low flow discharge of the Hai River into the ocean. Furthermore, the simulated result for the density current and solute transport processes clarified that these water cycle changes have caused serious seawater intrusion and a decrease of crop productivity in the coastal area, as shown by the gradient of NDVI (Normalized Difference Vegetation Index) estimated from satellite images. This study has important implications for the evaluation of ecosystems and environments located on the moving edge of freshwater and marine areas. Copyright © 2011 John Wiley & Sons, Ltd.
T2 preparation method for measuring hyperemic myocardial O2 consumption: in vivo validation by positron emission tomography
Authors: McCommis Kyle S. , O'Connor Robert , Abendschein Dana R. , Muccigrosso David , Gropler Robert J. , Zheng Jie 
Published: January 2011

AbstractPurposeTo validate a new T2‐prepared method for the quantification of regional myocardial O2 consumption during pharmacologic stress with positron emission tomography (PET).Materials and MethodsA T2 prepared gradient‐echo sequence was modified to measure myocardial T2 within a single breath‐hold. Six beagle dogs were randomly selected for the induction of coronary artery stenosis. Magnetic resonance imaging (MRI) experiments were performed with the T2 imaging and first‐pass perfusion imaging at rest and during either dobutamine‐ or dipyridamole‐induced hyperemia. Myocardial blood flow (MBF) was quantified using a previously developed model‐free algorithm. Hyperemic myocardial O2 extraction fraction (OEF) and consumption (MVO2) were calculated using a two‐compartment model developed previously. PET imaging using 11C‐acetate and 15O‐water was performed in the same day to validate OEF, MBF, and MVO2 measurements.ResultsThe T2‐prepared mapping sequence measured regional myocardial T2 with a repeatability of 2.3%. By myocardial segment‐basis analysis, MBF measured by MRI is closely correlated with that measured by PET (R2 = 0.85, n = 22). Similar correlation coefficients were observed for hyperemic OEF (R2 = 0.90, n = 9, mean difference of PET – MRI = −2.4%) and MVO2 (R2 = 0.83, n = 7, mean difference = 4.2%).ConclusionThe T2‐prepared imaging method may allow quantitative estimation of regional myocardial oxygenation with relatively good accuracy. The precision of the method remains to be improved. J. Magn. Reson. Imaging 2011;33:320–327. © 2011 Wiley‐Liss, Inc.
Dynamic contrast‐enhanced MRI of primary rectal cancer: Quantitative correlation with positron emission tomography/computed tomography
Authors: Gu Jing , Khong Pek‐Lan , Wang Silun , Chan Queenie , Wu Ed X. , Law Wailun , Liu Rico Kingyin , Zhang Jingbo 
Published: January 2011

AbstractPurposeTo assess the correlations between parameters measured on dynamic contrast‐enhanced magnetic resonance imaging and 18F‐fluorodeoxyglucose positron emission tomography (FDG‐PET) in rectal cancer.Materials and MethodsTo assess the correlations between parameters measured on dynamic contrast‐enhanced MRI and FDG‐PET in rectal cancer.ResultsSignificant correlations were only demonstrated between kepand SUVmax (r = 0.587,P= 0.001), and kepand SUVmean (r = 0.562,P= 0.002). No significant differences were found in imaging parameters between well, moderately and poorly differentiated adenocarcinoma groups. However, there was a trend that higher imaging values were found in poorly differentiated adenocarcinomas.ConclusionPositive correlations were found between kepand SUV values in primary rectal adenocarcinomas suggesting an association between angiogenesis and metabolic activity and further reflecting that angiogenic activity in washout phase is better associated with tumor metabolism than the uptake phase. J. Magn. Reson. Imaging 2011;33:340–347. © 2011 Wiley‐Liss, Inc.
Interstitial MR lymphography in mice with gadopentetate dimeglumine and gadoxetate disodium
Authors: Sheng Fugeng , Inoue Yusuke , Kiryu Shigeru , Watanabe Makoto , Ohtomo Kuni 
Published: January 2011

AbstractPurposeTo investigate the utility of interstitial MR lymphography with gadopentetate dimeglumine (Gd‐DTPA) or gadoxetate disodium (Gd‐EOB‐DTPA) in mice.Materials and MethodsWe performed MR lymphography after the subcutaneous injection of Gd‐DTPA or Gd‐EOB‐DTPA (0.1, 0.5, or 2.0 μmol per mouse) into the right footpad in six healthy mice, and the time courses of contrast enhancement were assessed. Additionally, the lymphatic pathways from two distinct sites were assessed in tandem by interstitial MR lymphography studies.ResultsSubcutaneous injection of Gd‐DTPA or Gd‐EOB‐DTPA caused lymph node enhancement immediately after injection, followed by a rapid decline. Dose dependency was shown for the lymph node enhancement, and a high‐dose injection caused prominent visualization of the veins. Lymph node enhancement did not differ significantly between Gd‐DTPA and Gd‐EOB‐DTPA or between Gd‐EOB‐DTPA premixed and not premixed with bovine serum albumin. The tandem assessment of two lymphatic pathways was feasible, and image fusion aided detailed comparison.ConclusionInterstitial MR lymphography with Gd‐DTPA or Gd‐EOB‐DTPA allowed clear visualization of the lymphatic pathway in healthy mice, and no significant difference was found between the two agents. Their rapid kinetics limits the imaging timing window, however, facilitates repeated assessment in a single imaging session. J. Magn. Reson. Imaging 2011;33:490–497. © 2011 Wiley‐Liss, Inc.
Measuring bone erosion and edema in rheumatoid arthritis: A comparison of manual segmentation and RAMRIS methods
Authors: Crowley Angela R. , Dong Jing , McHaffie Alex , Clarke Andrew W. , Reeves Quentin , Williams Megan , Robinson Elizabeth , Dalbeth Nicola , McQueen Fiona M. 
Published: January 2011

AbstractPurposeTo investigate the reliability, feasibility, and validity of a computer‐assisted manual segmentation (outlining) technique for measuring magnetic resonance imaging (MRI) bone erosion and edema at the wrist in rheumatoid arthritis (RA).Materials and MethodsThe 3T MRI scans were obtained in 22 RA patients (<2 years). Bone erosion and edema volumes were scored by two readers using outlining and were compared with RAMRIS scores.ResultsUsing outlining, intraobserver reliability for erosions and edema was high: intraclass correlation coefficients (ICCs) = 0.994 (0.991, 0.997) and 0.996 (0.994, 0.998), respectively (Reader 1). Interobserver reliability was high for bone erosion (ICC [90% confidence interval, CI] = 0.80 [0.64, 0.92]) and comparable to RAMRIS scoring (ICC 0.78 [0.64, 0.92]), but was only moderate for bone edema (0.46 [0.00, 0.96]), compared with RAMRIS (ICC = 0.84 [0.73, 0.94]). The methods were highly correlated for erosion scores, r = 0.90, 0.82 (Readers 1 and 2) and moderately correlated for edema, r = 0.57, 0.87.ConclusionSegmentation (outlining) can be used to measure the volume of MRI bone erosion and edema at the wrist in RA patients. When compared with RAMRIS scoring, outlining had similar reliability for quantifying erosions but reliability was lower for bone edema, possibly reflecting difficulty delineating the borders of affected bone. J. Magn. Reson. Imaging 2011;33:364–371. © 2011 Wiley‐Liss, Inc.
Cardiovascular magnetic resonance imaging for accurate sizing of the left atrium: Predictability of pulmonary vein isolation success in patients with atrial fibrillation
Authors: Jahnke Cosima , Fischer Julia , Mirelis Jesus Gonzalez , Kriatselis Charalampos , Gerds‐Li Jin‐Hong , Gebker Rolf , Manka Robert , Schnackenburg Bernhard , Fleck Eckart , Paetsch Ingo 
Published: January 2011

AbstractPurposeTo prospectively determine the most reproducible approach for left‐atrial size assessment using cardiovascular magnetic resonance (CMR) imaging in patients with atrial fibrillation and its value for prediction of pulmonary vein isolation (PVI) treatment success.Materials and MethodsEighty patients underwent CMR imaging prior to PVI; the CMR examination included standard cine sequences, a multislice cine sequence in 4‐chamber orientation with full left‐atrial coverage, and a contrast‐enhanced MR angiography of the left atrium. Left‐atrial size was determined as: diameter, area, volume segmented from angiography, and diastolic/systolic volumes from cine imaging (Simpson's rule). All measurements were carried out by two independent observers and repeated by one observer to assess inter‐ and intrareader variability. Treatment success was defined as persisting sinus rhythm after PVI (follow‐up period 12.6 ± 6.6 months).ResultsAll left‐atrial measurements showed substantial intrareader agreement. Interreader agreement was substantial for diastolic/systolic left‐atrial volumes only. Calculated bias was found to be minimal (0.1%–4.9%). Predictability of PVI treatment success was best using cine volumetric measurements (cutoff value for diastolic volume, 112 mL) yielding a sensitivity and specificity of 80% and 70%, respectively.ConclusionLeft‐atrial volumetry based on cine imaging represented the most reproducible approach to determine left‐atrial size. PVI success was predicted best using cine volumetry. J. Magn. Reson. Imaging 2011;33:455–463. © 2011 Wiley‐Liss, Inc.
Cardiovascular MRI for the assessment of heart failure: Focus on clinical management and prognosis
Authors: Muzzarelli Stefano , Ordovas Karen , Higgins Charles B. 
Published: January 2011

AbstractCardiovascular MR (CMR) has an emerging role in the noninvasive diagnostic assessment of heart failure (HF). Different imaging sequences allow for a detailed assessment of cardiac morphology, function, myocardial perfusion, tissue characterization, and blood flow measurement. This article reviews the key applications of CMR in HF, with special focus on how CMR may influence the diagnostic and therapeutic approach of HF patients. J. Magn. Reson. Imaging 2011;33:275–286. © 2011 Wiley‐Liss, Inc.
Whole‐brain cerebral blood flow mapping using 3D echo planar imaging and pulsed arterial tagging
Authors: Gai Neville D. , Talagala S. Lalith , Butman John A. 
Published: January 2011

AbstractPurposeTo quantitate cerebral blood flow (CBF) in the entire brain using the 3D echo planar imaging (EPI) PULSAR (pulsed star labeling) technique.Materials and MethodsThe PULSAR technique was modified to 1) incorporate a nonselective inversion pulse to suppress background signal; 2) to use 3D EPI acquisition; and 3) to modulate flip angle in such a manner as to minimize the blurring resulting from T1 modulation along the slice encoding direction. Computation of CBF was performed using the general kinetic model (GKM). In a series of healthy volunteers (n = 12), we first investigated the effects of introducing an inversion pulse on the measured value of CBF and on the temporal stability of the perfusion signal. Next we investigated the effect of flip angle modulation on the spatial blurring of the perfusion signal. Finally, we evaluated the repeatability of the CBF measurements, including the influence of the measurement of arterial blood magnetization (a calibration factor for the GKM).ResultsThe sequence provides sufficient perfusion signal to achieve whole brain coverage in ≈5 minutes. Introduction of the inversion pulse for background suppression did not significantly affect computed CBF values, but did reduce the fluctuation in the perfusion signal. Flip angle modulation reduced blurring, resulting in higher estimates of gray matter (GM) CBF and lower estimates of white matter (WM) CBF. The repeatability study showed that measurement of arterial blood signal did not result in significantly higher error in the perfusion measurement.ConclusionImprovements in acquisition and sequence preparation presented here allow for better quantification and localization of perfusion signal, allowing for accurate whole‐brain CBF measurements in 5 minutes. J. Magn. Reson. Imaging 2011;33:287–295. © 2011 Wiley‐Liss, Inc.