bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stereoselective Synthesis of Benzylated Prodelphinidins and Their Diastereomers with Use of the Mitsunobu Reaction in the Preparation of Their Gallocatechin Precursors
Authors: Krohn Karsten , Ahmed Ishtiaq , John Markus , Letzel Matthias C. , Kuck Dietmar 
Published: March 2010

AbstractThe tetrabenzylated catechin 9 was prepared by benzylation of the commercially available pure (+)‐catechin (3) and coupled with the commercially unavailable pentabenzylated(–)‐gallocatechin 10, prepared in a one‐step Mitsunobu‐type cyclization of the triol 8. The highly stereoselective synthesis of benzylated prodelphinidins – catechin‐(4α→8)‐gallocatechin (13), gallocatechin‐(4α→8)‐gallocatechin (14), and gallocatechin‐(4α→8)‐catechin (15) – is reported for the first time. The ESI(+)‐CID mass spectra of the coupling products were found to feature regioselective retro‐Diels–Alder (RDA) reactions and unusual sequential losses of pairs of C7H7· radicals (182 u) from the Na+ adduct ions.
Facile Synthesis of Selenium‐Containing Bicyclic β‐Lactams through Enyne Metathesis
Authors: Bankar Deepali B. , Koketsu Mamoru 
Published: March 2010

AbstractNovel selenium‐containing bicyclic β‐lactams were obtained through stereoselective insertion of (but‐3‐enyl)seleno and propargylseleno moieties at the C(4) positions of azetidinones with subsequent ring‐closing enyne metathesis.
meso‐Indolo[3,2‐b]carbazolyl‐Substituted Porphyrinoids: Synthesis, Characterization and Effect of the Number of Indolocarbazole Moieties on the Photophysical Properties
Authors: Maes Wouter , Ngo Thien H. , Rong Gu , Starukhin Aleksander S. , Kruk Mikalai M. , Dehaen Wim 
Published: March 2010

Abstractmeso‐Indolocarbazolylporphyrins endowed with a different number of indolocarbazole units have been synthesized via condensation of an appropriately substituted monoformylated 5,11‐dihydroindolo[3,2‐b]carbazole precursor and mesityldipyrromethane. Under specific conditions, analogous meso‐indolocarbazolylcorroles could also be prepared. The photophysical features of the novel luminescent free‐base and Zn‐porphyrin derivatives were investigated. The introduction of indolocarbazole substituents results in progressive bathochromic shifts of the porphyrin absorbance and fluorescence bands due to the rising energy of the a2u orbital. The excitation energy is efficiently transferred from the meso‐indolocarbazole units to the porphyrin macrocycle. An increased number of indolocarbazole moieties does not lead to porphyrin fluorescence quenching; on the contrary, a small increase of the fluorescence quantum yield is observed. The main route for excitation energy deactivation of all the studied porphyrins is intersystem S1→T1 crossing, with the intersystem crossing quantum yield, as determined by the photosensitized formation of singlet molecular oxygen, being as high as about 70 % for the free‐bases and more than 80 % for the Zn complexes. The intersystem crossing quantum yield seems to be barely affected by meso‐indolocarbazole substitution. A noticeable part of the excitation energy was found to deactivate through radiationless internal S1→S0 conversion.
Separation of DNA‐containing organelles from Toxoplasma gondii by CZE
Authors: Moe Morten K. , Samuelsen Per‐Jostein , Nielsen Henrik V. , Nielsen Kaare M. 
Published: March 2010

AbstractToxoplasma gondii and other members of the family Apicomplexa have two organelles, in addition to the nucleus, that contain DNA. Herein is reported the separation of the DNA‐carrying organelles from T. gondii tachyzoites, i.e. the mitochondrion and the apicoplast, by CZE. The cells were stained with SYTO9, a dye that exhibit fluorescence when interacting with double stranded nucleic acids (e.g. DNA) and disrupted by nitrogen cavitation. Following careful removal of the heavier cellular material, the remaining lysate was injected on a CE instrument and the DNA‐containing organelles were detected by LIF. The mitochondrion had longer migration time than the apicoplast, and the migration times were comparable in the replicates. This method should potentially also work for other members of the Apicomplexa including Plasmodium falciparum.
Effects of inactivation methods on the analysis of Bacillus atrophaeus endospores using real‐time PCR and MALDI‐TOF‐MS
Authors: Talbot Steven R. , Russmann Heiko , Köhne Stefan , Niederwöhrmeier Bärbel , Grote Gudrun , Scheper Thomas 
Published: March 2010

AbstractA wide range of analytical methods are available for the detection and identification of biological warfare agents. These technologies are often hampered in their performance when the inactivated samples are analyzed. To work with pathogens outside of biosafety level 3 laboratories, a complete inactivation is mandatory when appropriate protection equipment is unavailable. When methods of inactivation are used, the detection of bacteria becomes more difficult. In contrast to measuring viable organisms, inactivation steps can have a massive impact on the intrinsic cellular information. This study examined the effects of autoclaving and chemical inactivation methods on Bacillus spores using biological warfare detection setups like real‐time PCR and MALDI‐TOF‐MS. Here, the inactivation of Bacillus atrophaeus spores with formaldehyde, which is a suggested model for biological warfare spore agents, was compared with other inactivation reagents like Wofasteril®E400, a commercially available decontaminant based on peroxyacetic acid. With Wofasteril®E400 the critical factor of inactivation time was reduced to about 15 min and a limit of detection of 8500 spores by PCR was still measurable using five‐times‐washed spores. It has also been shown that MALDI‐TOF‐MS peak information can be hampered by inactivation methods.
Feature‐based adaptive mesh refinement for wingtip vortices
Authors: Kasmai N. , Thompson D. , Luke E. , Jankun‐Kelly M. , Machiraju R. 
Published: March 2010

AbstractFeature‐based solution‐adaptive mesh refinement is an attractive strategy when it is knowna priorithat the resolution of certain key features is critical to achieving the objectives of a simulation. In this paper, we apply vortex characterization techniques, which are typically employed to visualize vortices, to identify regions of the computational domain for mesh refinement. We investigate different refinement strategies that are facilitated by these vortex characterization techniques to simulate the flow past a wing in a wind tunnel. Our results, which we compare with experimental data, indicate that it is necessary to refine the region within and near the vortex extent surface to obtain an accurate prediction. Application of the identified mesh refinement strategy also produced observed improvement in the results predicted for a spinning missile with deflected canards. Copyright © 2010 John Wiley & Sons, Ltd.
A new fully non‐hydrostatic 3D free surface flow model for water wave motions
Authors: Ai Congfang , Jin Sheng , Lv Biao 
Published: March 2010

AbstractA new fully non‐hydrostatic model is presented by simulating three‐dimensional free surface flow on a vertical boundary‐fitted coordinate system. A projection method, known as pressure correction technique, is employed to solve the incompressible Euler equations. A new grid arrangement is proposed under a horizontal Cartesian grid framework and vertical boundary‐fitted coordinate system. The resulting model is relatively simple. Moreover, the discretized Poisson equation for pressure correction is symmetric and positive definite, and thus it can be solved effectively by the preconditioned conjugate gradient method. Several test cases of surface wave motion are used to demonstrate the capabilities and numerical stability of the model. Comparisons between numerical results and analytical or experimental data are presented. It is shown that the proposed model could accurately and effectively resolve the motion of short waves with only two layers, where wave shoaling, nonlinearity, dispersion, refraction, and diffraction phenomena occur. Copyright © 2010 John Wiley & Sons, Ltd.
The impact of college student socialization, social class, and race on need for cognition
Authors: Padgett Ryan D. , Goodman Kathleen M. , Johnson Megan P. , Saichaie Kem , Umbach Paul D. , Pascarella Ernest T. 
Published: March 2010

AbstractUsing longitudinal data, this chapter expands the use of Weidman's Model of Undergraduate Socialization by applying it to components of college student socialization, social class, and race and how these elements work together to influence need for cognition.
Nitric oxide, lipid peroxidation and total thiol levels in acute appendicitis
Authors: Yilmaz Fatma Meriç , Yilmaz Gülsen , Erol Mehmet Fatih , Köklü Seyfettin , Yücel Dogˇan 
Published: March 2010

AbstractBackground: The mechanisms involved in the pathology of acute appendicitis (AA) and the factors affecting the progression have still been investigated. Oxidative stress is one of the factors of interest. Nitric oxide (NO) and its role in AA has not been studied previously.Methods: Thirty‐four patients who underwent operation with a perioperative diagnosis of AA and 16 age and sex‐matched controls were included in the study. Serum thiobarbituric acid reactive substances (TBARS), thiol groups (SH), NO metabolites (NOx), and conventional inflammation markers were determined.Results: NOx, TBARS, C‐reactive protein (CRP) levels, white blood cell (WBC) count, and erythrocyte sedimentation rate (ESR) were significantly higher, and total SH was significantly lower in AA than in control group. NOx, TBARS, and SH levels were comparable in acute phlegmonous appendicitis and advanced appendicitis. There was a significant positive correlation between NOxand TBARS, CRP, ESR, WBC and a significant negative correlation between NOxand SH.Conclusions:Serum NOxlevels and oxidative stress elevate in AA independent from the extent of the lesion. Increased NO may play a role in the increased oxidative stress in AA. J. Clin. Lab. Anal. 24:63–66, 2010. © 2010 Wiley‐Liss, Inc.
SWI/SNF chromatin remodeling enzyme ATPases promote cell proliferation in normal mammary epithelial cells
Authors: Cohet Nathalie , Stewart Kathleen M. , Mudhasani Rajini , Asirvatham Ananthi J. , Mallappa Chandrashekara , Imbalzano Karen M. , Weaver Valerie M. , Imbalzano Anthony N. , Nickerson Jeffrey A. 
Published: March 2010

AbstractThe ATPase subunits of the SWI/SNF chromatin remodeling enzymes, Brahma (BRM) and Brahma‐related gene 1 (BRG1), can induce cell cycle arrest in BRM and BRG1 deficient tumor cell lines, and mice heterozygous for Brg1 are pre‐disposed to breast tumors, implicating loss of BRG1 as a mechanism for unregulated cell proliferation. To test the hypothesis that loss of BRG1 can contribute to breast cancer, we utilized RNA interference to reduce the amounts of BRM or BRG1 protein in the nonmalignant mammary epithelial cell line, MCF‐10A. When grown in reconstituted basement membrane (rBM), these cells develop into acini that resemble the lobes of normal breast tissue. Contrary to expectations, knockdown of either BRM or BRG1 resulted in an inhibition of cell proliferation in monolayer cultures. This inhibition was strikingly enhanced in three‐dimensional rBM culture, although some BRM‐depleted cells were later able to resume proliferation. Cells did not arrest in any specific stage of the cell cycle; instead, the cell cycle length increased by approximately 50%. Thus, SWI/SNF ATPases promote cell cycle progression in nonmalignant mammary epithelial cells. J. Cell. Physiol. 223:667–678, 2010. © 2010 Wiley‐Liss, Inc.
Role of voltage‐gated potassium channels in the fate determination of embryonic stem cells
Authors: Ng Sze‐Ying , Chin Chi‐Hou , Lau Yuen‐Ting , Luo Jialie , Wong Chun‐Kit , Bian Zhao‐Xiang , Tsang Suk‐Ying 
Published: March 2010

AbstractEmbryonic stem cells (ESCs) possess two unique characteristics: self‐renewal and pluripotency. In this study, roles of voltage‐gated potassium channels (Kv) in maintaining mouse (m) ESC characteristics were investigated. Tetraethylammonium (TEA+), a Kv blocker, attenuated cell proliferation in a concentration‐dependent manner. Possible reasons for this attenuation, including cytotoxicity, cell cycle arrest and differentiation, were examined. Blocking Kv did not change the viability of mESCs. Interestingly, Kv inhibition increased the proportion of cells in G0/G1 phase and decreased that in S phase. This change in cell cycle distribution can be attributed to cell cycle arrest or differentiation. Loss of pluripotency as determined at both molecular and functional levels was detected in mESCs with Kv blockade, indicating that Kv inhibition in undifferentiated mESCs directs cells to differentiate instead of to self‐renew and progress through the cell cycle. Membrane potential measurement revealed that Kv blockade led to depolarization, consistent with the role of Kv as the key determinant of membrane potential. The present results suggest that membrane potential changes may act as a “switch” for ESCs to decide whether to proliferate or to differentiate: hyperpolarization at G1 phase would favor ESCs to enter S phase while depolarization would favor ESCs to differentiate. Consistent with this notion, S‐phase‐synchronized mESCs were found to be more hyperpolarized than G0/G1‐phase‐synchronized mESCs. Moreover, when mESCs differentiated, the differentiation derivatives depolarized at the initial stage of differentiation. This investigation is the first study to provide evidence that Kv and membrane potential affect the fate determination of ESCs. J. Cell. Physiol. 224:165–177, 2010 © 2010 Wiley‐Liss, Inc.
LPLI inhibits apoptosis upstream of Bax translocation via a GSK‐3β‐inactivation mechanism
Authors: Zhang Lingling , Zhang Yingjie , Xing Da 
Published: March 2010

AbstractLow‐power laser irradiation (LPLI), a non‐damage physical therapy, which has been used clinically for decades of years, is shown to promote cell proliferation and prevent apoptosis. However, the underlying mechanisms that LPLI prevents cell apoptosis remain undefined. In this study, based on real‐time single‐cell analysis, we demonstrated for the first time that LPLI inhibits staurosporine (STS)‐induced cell apoptosis by inactivating the GSK‐3β/Bax pathway. LPLI could inhibit the activation of GSK‐3β, Bax, and caspase‐3 induced by STS. In the searching for the mechanism, we found that, LPLI can activate Akt, which was consistence with our former research, even in the presence of STS. In this anti‐apoptotic process, the interaction between Akt and GSK‐3β increased gradually, indicating Akt interacts with and inactivates GSK‐3β directly. Conversely, LPLI decreased the interaction between GSK‐3β and Bax, with the suppression of Bax translocation to mitochondria, suggesting LPLI inhibits Bax translocation through inactivating GSK‐3β. These results were further confirmed by the experiments of co‐immunoprecipitation. Wortmannin, an inhibitor of phosphatidylinositol 3′‐OH kinase (PI3K), potently suppressed the activation of Akt and subsequent anti‐apoptotic processes induced by LPLI. Taken together, we conclude that LPLI protects against STS‐induced apoptosis upstream of Bax translocation via the PI3K/Akt/GSK‐3β pathway. These findings raise the possibility of LPLI as a promising therapy for neuron‐degeneration disease induced by GSK‐3β. J. Cell. Physiol. 224:218–228, 2010 © 2010 Wiley‐Liss, Inc.
TNF‐α induces matrix metalloproteinase‐9 expression in A549 cells: Role of TNFR1/TRAF2/PKCα‐dependent signaling pathways
Authors: Lee I‐Ta , Lin Chih‐Chung , Wu Yang‐Chang , Yang Chuen‐Mao 
Published: March 2010

AbstractMatrix metalloproteinases (MMPs), in particular MMP‐9, have been shown to be induced by cytokines, including TNF‐α and contributes to airway inflammation. However, the mechanisms underlying TNF‐α‐induced MMP‐9 expression in human A549 cells remain unclear. Here, we report that TNF‐α‐induced MMP‐9 gene expression was mediated through the TNFR1/TRAF2/PKCα‐dependent signaling pathways in A549 cells, determined by zymographic, RT‐PCR, and Western blotting analyses. TNF‐α‐induced MMP‐9 expression was reduced by pretreatment with a TNFR Ab. Furthermore, TNF‐α‐induced TNFR1 and TRAF2 complex formation was revealed by immunoprecipitation using an anti‐TNFR1 Ab followed by Western blot analysis against an anti‐TRAF2 or anti‐TNFR1 Ab. In addition, TNF‐α‐induced MMP‐9 expression was also reduced by pretreatment with the inhibitor of PKCα (Gö6983), c‐Src (PP1), EGFR (AG1478), or PI3K (LY294002) or transfection with siRNAs of PKCα, Src, EGFR, Akt, p65, p300, and c‐Jun. On the other hand, TNF‐α stimulated the phosphorylation of c‐Src, EGFR, Akt, JNK1/2, and c‐Jun, which were inhibited by pretreatment with Gö6983. We also showed that TNF‐α induced Akt translocation and the formation of an Akt/p65/p300 complex. Pretreatment with the inhibitor of JNK1/2 (SP600125) but not the inhibitor of MEK1/2 (U0126), p38 MAPK (SB202190), or PI3K (LY294002), markedly inhibited TNF‐α‐induced c‐Jun mRNA levels. Taken together, these data suggest that in A549 cells, TNF‐α induces MMP‐9 expression via the TNFR1/TRAF2/PKCα‐dependent JNK1/2/c‐Jun and c‐Src/EGFR/PI3K/Akt pathways. J. Cell. Physiol. 454–464, 2010. © 2010 Wiley‐Liss, Inc.
Semi‐specific biosensors for measuring BOD in dairy wastewater
Authors: Raud Merlin , Linde Evelin , Kibena Elo , Velling Siiri , Tenno Toomas , Talpsep Ene , Kikas Timo 
Published: March 2010

AbstractBACKGROUND: Semi‐specific microbial biochemical oxygen demand (BOD) biosensors were constructed using living cells of Escherichia coli R17.1.3 (E. coli) and Raoultella terrigena P74.3 (R. terrigena) immobilized in agarose gel matrix. The research involved comparison with the Pseudomonas fluorescens P75 (P. fluorescens) biosensor that had no specificity in decomposing lactose and milk derivates. The constructed BOD biosensors were calibrated with OECD synthetic wastewater and tested with different wastewater samples.RESULTS: The linear range of the calibration curve was 5–200 mg L−1 BOD7 for R. terrigena and P. fluorescens based biosensors and 150 mg L−1 BOD7 for the E. coli based biosensor. Service life was 60 days for E. coli and P. fluorescens based biosensors and 40 days for R. terrigena based biosensors. BOD values for dairy industry wastewater obtained with current semi‐specific biosensors considerably overestimate BOD7, while universal biosensors underestimate BOD7 obtained by the conventional 7‐day BOD test.CONCLUSION: In spite of extensive overestimation of BOD7 the semi‐specific biosensors enabled better estimation of BOD in dairy industry wastewater than a reference P. fluorescens biosensor. The best result, in terms of service life, stability, sensitivity and reproducibility was accomplished with semi‐specific E.coli biosensor. Copyright © 2010 Society of Chemical Industry
Millennial precipitation reconstruction for the Jemez Mountains, New Mexico, reveals changingb drought signal
Authors: Touchan Ramzi , Woodhouse Connie A. , Meko David M. , Allen Craig 
Published: March 2010

AbstractDrought is a recurring phenomenon in the American Southwest. Since the frequency and severity of hydrologic droughts and other hydroclimatic events are of critical importance to the ecology and rapidly growing human population of this region, knowledge of long‐term natural hydroclimatic variability is valuable for resource managers and policy‐makers. An October–June precipitation reconstruction for the period AD 824–2007 was developed from multi‐century tree‐ring records of Pseudotsuga menziesii (Douglas‐fir), Pinus strobiformis (Southwestern white pine) and Pinus ponderosa (Ponderosa pine) for the Jemez Mountains in Northern New Mexico. Calibration and verification statistics for the period 1896–2007 show a high level of skill, and account for a significant portion of the observed variance (>50%) irrespective of which period is used to develop or verify the regression model. Split‐sample validation supports our use of a reconstruction model based on the full period of reliable observational data (1896–2007). A recent segment of the reconstruction (2000–2006) emerges as the driest 7‐year period sensed by the trees in the entire record. That this period was only moderately dry in precipitation anomaly likely indicates accentuated stress from other factors, such as warmer temperatures. Correlation field maps of actual and reconstructed October–June total precipitation, sea surface temperatures and 500‐mb geopotential heights show characteristics that are similar to those indicative of El Niño–Southern Oscillation patterns, particularly with regard to ocean and atmospheric conditions in the equatorial and north Pacific. Our 1184‐year reconstruction of hydroclimatic variability provides long‐term perspective on current and 20th century wet and dry events in Northern New Mexico, is useful to guide expectations of future variability, aids sustainable water management, provides scenarios for drought planning and as inputs for hydrologic models under a broader range of conditions than those provided by historical climate records. Copyright © 2010 Royal Meteorological Society
Statistical analysis of observed and simulated hourly surface wind in the vicinity of the Panama Canal
Authors: Cheng Fang‐Yi , Georgakakos Konstantine P. 
Published: March 2010

AbstractSurface wind patterns at the Panama Canal vicinity are identified on the basis of 6 years of observed hourly surface wind data and with the use of high‐resolution numerical model simulations. Statistical analysis of the observed wind at various stations in the Panama Canal is presented, together with the analysis of simulated surface wind fields that are obtained from the MM5 mesoscale meteorological model using surface wind assimilation and forced by North American regional reanalysis data. The performance analysis indicates that the 2‐km‐resolution MM5 model surface wind simulations have skill when compared with the observations at the measurement sites. The analysis of the wind fields for the period 2002–2007 shows that the dry season (January to April) is more spatially and temporally coherent than the wet season in the region. The simulated wind shows that the average wind speed reaches up to 7–8 m s−1and the frequency of exceeding 5 m s−1reaches up to 0.7–0.8 in Lake Gatun, the entrance/exit of the Canal in the Caribbean and Pacific coasts, and at high elevations. The dry season exhibits higher climatological wind speeds and exceedence frequencies than the wet season but the wet season shows greater spatial variability. For both seasons, the morning hours have lower average winds than the evening hours. The analysis underlines the significant influence of convection, sea breeze and local conditions (elevation gradients and land surface cover) in the observed and simulated surface wind patterns.The information presented herein, particularly as regards the Canal centerline results, may be useful for identifying the effects of air pollution from sources aboard transiting cargo ships on large communities in the Canal vicinity (e.g. Panama City). Information presented is also relevant to regional wind energy studies and fog formation analyses. Copyright © 2010 Royal Meteorological Society