bluuebunny/crossref_metadata_2025_split huggingface dataset:
Automated detection of rare‐event pathogens through time‐gated luminescence scanning microscopy
Authors: Lu Yiqing , Jin Dayong , Leif Robert C. , Deng Wei , Piper James A. , Yuan Jingli , Duan Yusheng , Huo Yujing 
Published: April 2011

AbstractMany microorganisms have a very low threshold (<10 cells) to trigger infectious diseases, and, in these cases, it is important to determine the absolute cell count in a low‐cost and speedy fashion. Fluorescent microscopy is a routine method; however, one fundamental problem has been associated with the existence in the sample of large numbers of nontarget particles, which are naturally autofluorescent, thereby obscuring the visibility of target organisms. This severely affects both direct visual inspection and the automated microscopy based on computer pattern recognition. We report a novel strategy of time‐gated luminescent scanning for accurate counting of rare‐event cells, which exploits the large difference in luminescence lifetimes between the lanthanide biolabels, >100 μs, and the autofluorescence backgrounds, <0.1 μs, to render background autofluorescence invisible to the detector. Rather than having to resort to sophisticated imaging analysis, the background‐free feature allows a single‐element photomultiplier to locate rare‐event cells, so that requirements for data storage and analysis are minimized to the level of image confirmation only at the final step. We have evaluated this concept in a prototype instrument using a 2D scanning stage and applied it to rare‐event Giardia detection labeled by a europium complex. For a slide area of 225 mm2, the time‐gated scanning method easily reduced the original 40,000 adjacent elements (0.075 mm × 0.075 mm) down to a few “elements of interest” containing the Giardia cysts. We achieved an averaged signal‐to‐background ratio of 41.2 (minimum ratio of 12.1). Such high contrasts ensured the accurate mapping of all the potential Giardia cysts free of false positives or negatives. This was confirmed by the automatic retrieving and time‐gated luminescence bioimaging of these Giardia cysts. Such automated microscopy based on time‐gated scanning can provide novel solutions for quantitative diagnostics in advanced biological, environmental, and medical sciences. © 2011 International Society for Advancement of Cytometry
Time‐domain equalizer for multicarrier systems in impulsive noise
Authors: Tan Yee Chieh , Ramli Nordin Bin , Chuah Teong Chee 
Published: April 2011

SUMMARYIn multicarrier communication systems, a time‐domain equalizer (TEQ) can be applied to shorten the channel impulse response and to eliminate inter‐symbol interference (ISI). However, the presence of impulsive noise in the channel may paralyze the operation of TEQs and subsequently lead to poor error performance. In this paper, a multicarrier receiver that incorporates a constant false alarm rate algorithm and an iterative estimation technique (CFAR‐IET) in conjunction with a TEQ is proposed to increase the robustness of the receiver against impulsive noise. Furthermore, an improved version of the CFAR‐IET‐TEQ scheme, which uses the buffering, sorting, removing and amplitude averaging (BSRA) processes, is presented. Performance comparisons of the proposed schemes with the existing Gaussian‐optimized schemes are made. Simulation results show that the BSRA‐IET‐TEQ scheme is an effective approach to reduce symbol error rate (SER) in impulsive channels while performing satisfactorily in Gaussian channels. Copyright © 2011 John Wiley & Sons, Ltd.
Significantly Enhanced CO2/CH4 Separation Selectivity within a 3D Prototype Metal–Organic Framework Functionalized with OH Groups on Pore Surfaces at Room Temperature
Authors: Chen Zhenxia , Xiang Shengchang , Arman Hadi D. , Li Peng , Zhao Dongyuan , Chen Banglin 
Published: April 2011

AbstractA new three‐dimensional microporous metal–organic framework (MOF) Zn(BDC‐OH)(DABCO)0.5·(DMF)2(H2O) (UTSA‐25; H2BDC‐OH = 2‐hydroxybenzenedicarboxylic acid, DABCO = 1,4‐diazabicyclo[2.2.2]octane) with functional–OH groups on the pore surfaces was solvothermally synthesized and structurally characterized. UTSA‐25 features a three‐dimensional structure with 3D intercrossed channels of about 7.5 × 7.5, 3.2 × 4.7, and 3.2 × 4.7 Å2, respectively. The small pores and the functional –OH groups on the pore surfaces within the activated UTSA‐25a have enabled their strong interactions with CO2 of adsorption enthalpy of 22.5 kJ mol–1, which is higher than that of 17.5 kJ mol–1 in the original MOF Zn(BDC)(DABCO)0.5 without the functionalized –OH groups. Accordingly, CO2/CH4 separation selectivities in UTSA‐25a of 17.2 and 12.5 at 273 and 296 K, respectively, are much higher than those of 4.4 and 3.7 in Zn(BDC)(DABCO)0.5, thus highlighting UTSA‐25a as a very promising porous material for industrially important CO2/CH4 separation.
A Series of MnIII4MnII8 Single‐Molecule Magnets Mediated by Intra‐ and Intermolecular Interactions
Authors: Leng Ji‐Dong , Dian Long‐Yang , Liu Jun‐Liang , Tong Ming‐Liang 
Published: April 2011

AbstractThe solvothermal reaction of manganese(II) acetylacetonate [Mn(acac)2], 1,1,1‐tris(hydroxymethyl)ethane (H3thme), 1,1,1‐tris(hydroxymethyl)propane (H3thmp), and (CH3)3CCO2H leads to a series of mixed‐valence MnIII4MnII8clusters, [MnIII4MnII8(μ5‐O)2(μ3‐OMe)2(thme)4(Me3CCO2)10(H2O)2] (1), [MnIII4MnII8(μ5‐O)2(μ3‐OMe)2(thme)4(Me3CCO2)10(MeOH)2] (2), [MnIII4MnII8(μ5‐O)2(μ3‐OMe)2(thmp)4(Me3CCO2)10(H2O)2] (3), and [MnIII4MnII8(μ5‐O)2(μ3‐OMe)2(thmp)4(Me3CCO2)10(MeOH)2] (4). The MnIII4MnII8 cores of the complexes can be described as a central rhomboid [Mn4O6] layer sandwiched by two [Mn4O7] layers. Alternating current (AC) magnetization studies reveal that complexes 1–4 possess the S = 4 spin ground state and behave as single‐molecule magnets (SMMs). All four of the compounds clearly show slow magnetic relaxation behavior, but out‐of‐phase AC peaks above 1.8 K were only obtained for 3 and 4, thereby revealing that the ground‐state anisotropy of four Mn12 clusters are effectively modified by intra‐ and intermolecular interactions by substituting the tripodal ligands and terminal ligands.
SiFA‐Modified Phenylalanine: A Key Compound for the Efficient Synthesis of 18F‐Labelled Peptides
Authors: Iovkova Ljuba , Könning Daniel , Wängler Björn , Schirrmacher Ralf , Schoof Sebastian , Arndt Hans‐Dieter , Jurkschat Klaus 
Published: April 2011

AbstractBoth the racemic and the stereoselective synthesis of the silicon‐modified amino acid p‐(tBu2FSi)C6H4CH2(NH2)COOH (SiFA‐phenylalanine, 6) and its derivatives p‐(tBu2FSi)C6H4CH2(NHBoc)COOH (10) and p‐(tBu2FSi)C6H4CH2(NHFmoc)COOH (11) are reported. The latter two compounds are valuable building blocks for the convenient introduction of silicon‐based fluoride acceptors (SiFAs) into peptides by solid‐phase peptide syntheses (SPPS). As prove of principle, the Tyr3‐octreotate derivatives 12, 13 and 14 were prepared by using standard protocols of the solid‐phase peptide synthesis (SPPS). They were labelled with 18F‐fluorine by isotopic exchange in radiochemical yields of up to 70 % (with radiochemical purity ranging between 92 and 99 %). The incorporation of 18F‐fluorine into the SiFA‐modified amino acid 6 was studied as the latter may also serve as a tracer in PET. After purification, [18F]‐6 showed a remarkable stability in an isotonic solution. Also reported is the molecular structure, as determined by single‐crystal X‐ray diffraction analysis, of p‐(tBu2FSi)C6H4CHCH[C(O)OMe]NHC(O)OCH2Ph (8), which serves as a precursor for the stereoselective synthesis of compound 6.
Effects of urban air pollutants on elemental accumulation and identification of oxidative stress biomarkers in the transplanted lichen Pseudovernia furfuracea
Authors: Oztetik Elif , Cicek Arzu 
Published: April 2011

Abstract
Determining the origins of heavy metals, their accumulation, and their detoxification mechanisms constitutes a major problem in understanding environmental pollution in urban areas. The objective of this study was to detect the relative air quality in Eskisehir city center (Turkey) through the transplanted epiphytic lichen Pseudovernia furfuracea as a biomonitor of the concentrations of some heavy metals accumulated and to describe their toxic effects on lichen physiology during the study period of one year. The influence of heavy metal accumulations on macroelement levels were also examined. In addition to analysis of B, K, Ca, P, S, Al, Fe, Mg, Mn, Ni, Zn, Pb, and Cu, total soluble proteins and oxidative stress parameters through glutathione (GSH) contents and glutathione S-transferase (GST) activities were also determined. Results indicate that, although the heavy metal concentrations were found to be gradually increased from the unpolluted control zone to the city center, the concentrations of macroelements S and Ca were higher in the polluted area. However, B, K, Mg, and P elements were found to be higher in the unpolluted area than in the polluted zones. It seems that heavy metals induce oxidative stress in lichens; we found enhancement of GSH concentrations and GST activity. Most probably, the expected destruction in this organism was reduced by the intervention of antioxidant capacity. Therefore, this report confirms the fact that the epiphytic lichen P. furfuracea is a good model for biomonitoring atmospheric quality for a long-term transplantation study, and oxidative stress parameters stand out as a tool for an early environment assessment of other physiological parameters. Environ. Toxicol. Chem. 2011; 30:1629–1636. © 2011 SETAC
A method for overcoming the surface tension time step constraint in multiphase flows II
Authors: Sussman M. 
Published: April 2011

SUMMARYA method for overcoming the surface tension time step constraint is presented. The algorithm presented in this work is an improvement on the work presented by Sussman and Ohta (SIAM J Sci Comput 2009). In this work, the method of Sussman and Ohta is extended in order to treat problems with contact angle dynamics. Furthermore, this work presents a more efficient method for computing volume‐preserving motion by mean curvature than the method presented previously. The new method is tested on the following four 2D problems: (1) 3D axisymmetric (r−z) surface tension driven zero gravity droplet oscillation, (2) measurement of the magnitude of parasitic currents for a droplet on a substrate initialized in static equilibrium, (3) relaxation of a 2D droplet on a substrate to static shape, and (3) relaxation of a 2D bubble on a substrate to static shape. Copyright © 2011 John Wiley & Sons, Ltd.
Copy number profiling in von hippel‐lindau disease renal cell carcinoma
Authors: Shuib Salwati , Wei Wenbin , Sur Hariom , Morris Mark R. , McMullan Dominic , Rattenberry Eleanor , Meyer Esther , Maxwell Patrick H. , Kishida Takeshi , Yao Masahiro , Latif Farida , Maher Eamonn R. 
Published: April 2011

AbstractGermline mutations in the VHL tumor suppressor gene cause von Hippel‐Lindau (VHL) disease and somatic VHL mutations occur in the majority of clear cell renal cell carcinoma (cRCC). To compare copy number abnormalities (CNAs) between cRCC from VHL patients and sporadic cRCC cases without detectable somatic VHL mutations, we analyzed 34 cRCC with Affymetrix 250K arrays. To increase the power of the study, we then combined our results with those of a previously published study and compared CNAs in VHL and non‐VHL related cRCC using the genomic identification of significant targets in cancer (GISTIC) program. In VHL, cRCC GISTIC analysis identified four statistically significant regions of copy number gain and four statistically significant regions of deletion that occurred in >10% of tumors analyzed. Sporadic cRCC without detectable VHL mutations had, on average, more copy number abnormalities than VHL cRCC though the most common regions of loss/gain (e.g., 3p and 14q loss and 5q gain) were present in both tumor sets. However, CNAs on chromosome arms 7p (gain) and 8p (loss) were only detected in VHL RCC. Although individual copy number abnormality peaks contained clear candidate cancer genes in some cases (e.g., the 3p loss peak in VHL cRCC contained only six genes including VHL), most peaks contained many genes. To date, only a minority of the candidate genes included in these peaks have been analyzed for mutation or epigenetic inactivation in cRCC but TNFRSF10C and DUSP4 map to the 8p region deleted in VHL cRCC and TP53 and HIF2A (EPAS1) mapped to CNA loss and gain peaks (chromosomes 17 and 2, respectively) detected in sporadic VHL wild‐type cRCC. © 2011 Wiley‐Liss, Inc.
The miR‐15a‐miR‐16‐1 locus is homozygously deleted in a subset of prostate cancers
Authors: Porkka Kati P. , Ogg Erinn‐Lee , Saramäki Outi R. , Vessella Robert L. , Pukkila Heidi , Lähdesmäki Harri , van Weerden Wytske M. , Wolf Maija , Kallioniemi Olli P. , Jenster Guido , Visakorpi Tapio 
Published: April 2011

AbstractMicroRNAs (miRNAs) are small, non‐coding RNAs that negatively regulate the expression of protein coding genes. In this study, we screened highly informative prostate cancer cell lines and xenografts (n = 42) for miRNA gene copy number and expression changes. The expression profiling showed distinction between cell lines and xenografts as well as between androgen sensitive and independent models. Only a few copy number alterations that were associated with expression changes were identified. Most importantly, the miR‐15a‐miR‐16‐1 locus was found to be homozygously deleted in two samples leading to the abolishment of miR‐15a, but not miR‐16, expression. miR‐16 is also expressed from another genomic locus. Mutation screening of the miR‐15a‐miR‐16‐1 gene in the model systems as well as clinical samples (n = 50) revealed no additional mutations. In conclusion, our data indicate that putative tumor suppressors, miR‐15a and miR‐16‐1, are homozygously deleted in a subset of prostate cancers, further suggesting that these miRNAs could be important in the development of prostate cancer. © 2011 Wiley‐Liss, Inc.
Hematocrit and C‐reactive protein predict treatment response times in ADAMTS13‐deficient thrombotic microangiopathy
Authors: Samia Noelle I. , Friedman Kenneth D. , Gottschall Jerome L. , Raife Thomas J. 
Published: April 2011

AbstractThrombotic microangiopathy (TMA) syndromes are a heterogeneous group of microvascular syndromes that are typically treated with plasma exchange and other adjunctive therapies. Important pathogenic factors, such as ADAMTS13 deficiency, define distinct subsets of TMA. New treatments for TMA are being explored that are hypothesized to bring about remission more quickly. However, the existing factors that influence response to treatment time are poorly understood. We hypothesized that common laboratory parameters available at the time of treatment initiation might correlate with the number of days of plasma exchange required to induce remission. We therefore retrospectively compared pretreatment platelet counts, hematocrit levels, and C‐reactive protein (CRP) levels to the number of days of plasma exchange treatment in 27 ADAMTS13‐deficient TMA patients and 25 non‐ADAMTS13‐deficient patients that achieved remission. Using quantile regression analysis, we observed that in ADAMTS13‐deficient patients, higher initial hematocrit levels significantly correlated with shorter treatment response times. In addition, for ADAMTS13‐deficient patients, elevated levels of CRP correlated directly with longer response times. Higher platelet counts were associated with a nonsignificant trend toward shorter response times. In non‐ADAMTS13‐deficient TMA patients no significant correlations were observed. Our results suggest that when conducting clinical trials of adjunctive treatments for TMA, clinical data, including ADAMTS13 levels, pretreatment hematocrit levels, and CRP levels may be informative in interpreting response to treatment times. J. Clin. Apheresis, 2011. © 2011 Wiley‐Liss, Inc.
Effect of Na+, Mg2+, and Zn2+ chlorides on the structural and thermodynamic properties of water/n‐heptane interfaces
Authors: Rodríguez‐Ropero Francisco , Fioroni Marco 
Published: April 2011

AbstractThe effect on the structural and thermodynamic properties in water/n‐heptane interfaces on addition of NaCl, MgCl2, and ZnCl2 has been examined through five independent 100‐ns molecular dynamics simulations. Results indicate that the interfacial thickness within the framework of the capillary‐wave model decreases on addition of electrolytes in the order Na+ < Mg2+ < Zn2+, whereas the interfacial tension increases in the same order. Ionic density profiles and self‐diffusion coefficients are strongly influenced by the strength of the first hydration shell, which varies in the order Na+ < Mg2+ < Zn2+. On the other hand, the Cl− behavior, that is, diffusion and solvation sphere, is influenced by its counterion. Accordingly, cations are strongly expelled from the interface, which is especially remarkable for the small divalent cations. This fact alters the water geometry near the interface and in a lesser extent n‐heptane order and number of hydrogen bonds per water molecule close to the interface. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011
A forgotten social science? Creating a place for linguistics in the historical dialogue
Authors: Martin‐Nielsen Janet 
Published: April 2011

AbstractThe post–World War II era was one of great triumph for American linguists—and yet linguistics is all but absent from the historical literature on postwar social science. This paper aims to illuminate this curious situation: to understand its provenance, evaluate its merits, and contextualize it broadly. I argue that the historiographic lacuna results from two factors: (1) the opt‐out of linguists from the wider American social science community, and (2) historical‐developmental and ‐orientational factors that stand linguistics apart from the social science mainstream. The resultant isolation of linguistics has led to a parallel isolation in the historical literature. Ultimately, this paper poses a pivotal and timely question: How is the postwar social science space construed within the existing historiographic framework, and how should it be construed in order to maximize understanding? I propose a rethink of the received historiography centered on intellectual transformations and cross‐disciplinary integration. © 2011 Wiley Periodicals, Inc.
Regio‐ and stereoselective synthesis of 1‐benzopyrano[2,3‐b]pyrrolo[2,3‐d]pyridines: A microwave‐accelerated intramolecular [3+2] cycloaddition reaction of azomethine ylide
Authors: Maiti Sourav , Lakshmykanth T. M. , Panja Suman Kalyan , Mukhopadhyay Ranjan , Datta Ayan , Bandyopadhyay Chandrakanta 
Published: April 2011

AbstractRegio‐ and stereoselective syntheses of tetracyclic compounds having chromone, pyrrolidine, and piperidine rings have been accomplished by an intramolecular [3+2] cycloaddition reaction involving azomethine ylide. The reactions were carried out thermally as well as by irradiation with microwave. The latter process accelerates the reaction. The selectivities were investigated by density functional theory computation. J. Heterocyclic Chem., (2011).
Complexes of iron(III) and chromium(III) salen and salophen Schiff bases with bridging 1,3,5‐triazine derived multidirectional ligands
Authors: Koç Ziya Erdem 
Published: April 2011

AbstractA new synthetic route for preparing multidirectional ligands was developed by using 2,4,6‐trichloro‐1,3,5‐triazine (cyanuric chloride) as core. The reaction included the selective substitutions of 4‐aminobenzoic acid onto three chlorides of the triazine ring via a stepwise manner at 1:1, 1:2, or 1:3 equiv. and 0, 25, 130°C, respectively. An efficient synthesis of a novel class of “multidirectional ligands” has been developed based on high‐yielding chloride substitutions of 2,4,6‐trichloro‐1,3,5‐triazine by amines. Sixteen new mono‐, di‐, tri‐, and tetra‐nuclear Fe(III) and Cr(III) complexes involving tetradenta Schiff bases N,N′‐bis(salicylidene)ethylenediamine‐(salenH2) or bis(salicylidene)‐o‐phenylenediamine‐(salophenH2) with two new 1,3,5‐triazine derived multidirectional ligands were synthesized and characterized by means of elemental analysis, 1H NMR, FT‐IR spectroscopy, LC‐MS analysis, AAS, thermal analysis, and magnetic susceptibility measurements. The complexes were also characterized as low‐spin distorted octahedral Fe(III) and Cr(III) bridged by carboxylic acids. It was understood that the [{Fe(salen)/(salophen)}2O] and [{Cr(salen)/(salophen)}2O] containing compounds could be represented by the electronic structure of te and te. J. Heterocyclic Chem., (2011).
Stochastic simulation of rainfall in the semi‐arid Limpopo basin, Botswana
Authors: Kenabatho P. K. , McIntyre N. R. , Chandler R. E. , Wheater H. S. 
Published: April 2011

AbstractThe application of spatial‐temporal stochastic rainfall models to semi‐arid or arid areas is expected to be particularly challenging because of the high variability of rainfall, sparse rain gauge networks with significant periods of missing rainfall and potential data quality issues. In this article, a generalized linear model (GLM) has been fitted to daily rainfall data from the period 1975–1999 for 13 gauges in a 7660 km2 sub‐basin of the Limpopo basin in Botswana, with the objective of exploring applicability of the GLM for infilling historic records and for climate change analysis. Several relevant statistics of rainfall space‐time variability were used to analyse model performance, including use of an independent validation period and sites that were not used in the fitting. The GLM was considered to simulate rainfall adequately for the purpose of sub‐basin‐scale water resource studies, although the model uncertainty is high. The main factors affecting rainfall space‐time variability were found to be seasonality, autocorrelation of daily rainfall, altitude, latitude and longitude. Addition of large‐scale drivers of rainfall (pressure, humidity and temperature) further improved representation of inter‐annual variability, and this link to large‐scale climate potentially facilitates downscaling of global climate model outputs. Although the model was locally sensitive to data quality issues, there was no evidence that these issues affected sub‐basin scale analysis. Copyright © 2011 Royal Meteorological Society
Spatio‐temporal variation of daily extreme temperatures over Turkey
Authors: Toros Hüseyin 
Published: April 2011

AbstractExtreme (maximum and minimum) temperature records are analysed for search of spatio‐temporal variation patterns in regional climate change throughout Turkey based on 165 stations, as many stations as possible, and as far back as possible, in the period 1961–2008. The main purpose is to better understand the possibility of annual trends during the warm and cold periods. Homogeneity and Mann‐Kendall trend test methodologies are applied in order to identify statistically significant trends at each station. It is observed that there is a significant warming in both annual maximum and minimum temperature records. Increasing trends in warm period are comparatively stronger than cold periods so far as the maximum temperatures are concerned. There are also increasing trends in annual minimum temperature during warm periods with almost no change in minimum temperatures of cold periods. The observations indicate that the temperature began to increase in the beginning of the 1980s. Nine stations are chosen from different geographical regions in order to compare monthly average temperature values of 1961–1984 with 1985–2008 and a marked increase was observed on extreme temperatures in these stations. Copyright © 2011 Royal Meteorological Society