bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of ten hexabromocyclododecane diastereoisomers using two coupled reversed‐phase columns and liquid chromatography/tandem mass spectrometry
Authors: Han Qian , Song Han , Gao Shutao , Zeng Xiangying , Yu Zhiqiang , Yu Yunjiang , Sheng Guoying , Fu Jiamo 
Published: May 2014

RATIONALEHexabromocyclododecanes (HBCDs) are raising concern due to their potential persistence, bioaccumulation and toxicity. Apart from the widely reported isomers α‐, β‐, γ‐HBCD, other HBCD diastereoisomers such as δ‐HBCD have been also recently found in environmental media and biota. These newly reported diastereoisomers might give more insight into the degradation and biotransformation of HBCDs.METHODSA reversed‐phase C18 column coupled to a C8 column was used to improve the chromatographic resolution. A gradient mobile phase consisting of methanol, acetonitrile, and water, as well as tandem mass spectrometry parameters, were optimized. Ten HBCD diastereoisomers were finally determined by liquid chromatography/tandem mass spectrometry in multiple reaction monitoring mode with negative electrospray ionization.RESULTSEight of the ten HBCDs could be chromatographically separated by using the coupled reversed‐phase columns. Results of the method validation indicate high reproducibility and good sensitivity. The limit of detection ranged from 0.4 to 0.8 pg, and the relative standard deviations of intra‐ and inter‐day injections ranged from 1.8 to 5.1% and from 2.7 to 9.5%, respectively. The developed method was further applied to the analysis of HBCDs in HBCD commercial products and soil samples. δ‐, η‐, θ‐, and ε‐HBCD were detected in commercial products and soil samples.CONCLUSIONSThe present study revealed that δ‐, η‐, θ‐, and ε‐HBCD might occur ubiquitously in environmental media and biota. These newly reported diastereoisomers may help us to better understand the fate and transformation of HBCDs in the environment. Copyright © 2014 John Wiley & Sons, Ltd.
Total Synthesis of the Congested Propellane Alkaloid (−)‐Acutumine
Authors: Castle Steven L. 
Published: May 2014

AbstractThe enantioselective total synthesis of (−)‐acutumine is described. The synthetic strategy was inspired by the premise that the cyclohexenone ring could be derived from an aromatic precursor. After successful construction of a propellane model system, an initial attempt to prepare the spirocyclic subunit was thwarted by incorrect regioselectivity in a radical cyclization. A second‐generation approach involving a radical–polar crossover reaction was successful, and the chemistry developed in the aforementioned model system was then applied to synthesize the natural product. Key reactions included a phenolic oxidation, a diastereoselective ketone allylation utilizing Nakamura's chiral allylzinc reagent, an anionic oxy‐Cope rearrangement, an acid‐promoted cyclization of a secondary amine onto an α,β‐unsaturated ketal, and a regioselective methyl enol etherification of a 1,3‐diketone.
Developmental genetics of the Caenorhabditis elegans pharynx
Authors: Pilon Marc 
Published: May 2014

The Caenorhabditis elegans pharynx is a rhythmically pumping organ composed initially of 80 cells that, through fusions, amount to 62 cells in the adult worm. During the first 100 min of development, most future pharyngeal cells are born and gather into a double‐plate primordium surrounded by a basal lamina. All pharyngeal cells express the transcription factor PHA‐4, of which the concentration increases throughout development, triggering a sequential activation of genes with promoters responding differentially to PHA‐4 protein levels. The oblong‐shaped pharyngeal primordium becomes polarized, many cells taking on wedge shapes with their narrow ends toward the center, hence forming an epithelial cyst. The primordium then elongates, and reorientations of the cells at the anterior and posterior ends form the mouth and pharyngeal‐intestinal openings, respectively. The 20 pharyngeal neurons establish complex but reproducible trajectories using ‘fishing line’ and growth cone‐driven mechanisms, and the gland cells also similarly develop their processes. The genetics behind many fate decisions and morphogenetic processes are being elucidated, and reveal the pharynx to be a fruitful model for developmental biologists. WIREs Dev Biol 2014, 3:263–280. doi: 10.1002/wdev.139This article is categorized under:

Gene Expression and Transcriptional Hierarchies > Cellular Differentiation
Invertebrate Organogenesis > Worms
Nervous System Development > Worms
ON DEFICIENT-PERFECT NUMBERS
Authors: TANG MIN , FENG MIN 
Published: May 2014

AbstractFor a positive integer $\def \xmlpi #1{}\def \mathsfbi #1{\boldsymbol {\mathsf {#1}}}\let \le =\leqslant \let \leq =\leqslant \let \ge =\geqslant \let \geq =\geqslant \def \Pr {\mathit {Pr}}\def \Fr {\mathit {Fr}}\def \Rey {\mathit {Re}}n$, let $\sigma (n)$ denote the sum of the positive divisors of $n$. Let $d$ be a proper divisor of $n$. We call $n$ a deficient-perfect number if $\sigma (n) = 2n - d$. In this paper, we show that there are no odd deficient-perfect numbers with three distinct prime divisors.
Predicting CCHF incidence and its related factors using time-series analysis in the southeast of Iran: comparison of SARIMA and Markov switching models
Authors: ANSARI H. , MANSOURNIA M. A. , IZADI S. , ZEINALI M. , MAHMOODI M. , HOLAKOUIE-NAIENI K. 
Published: May 2014

SUMMARYCrimean-Congo haemorrhagic fever (CCHF) is endemic in the southeast of Iran. This study aimed to predict the incidence of CCHF and its related factors and explore the possibility of developing an empirical forecast system using time-series analysis of 13 years’ data. Data from 2000 to 2012 were obtained from the Health Centre of Zahedan University of Medical Sciences, Climate Organization and the Veterinary Organization in the southeast of Iran. Seasonal autoregressive integrated moving average (SARIMA) and Markov switching models (MSM) were performed to examine the potential related factors of CCHF outbreaks. These models showed that the mean temperature (°C), accumulated rainfall (mm), maximum relative humidity (%) and legal livestock importation from Pakistan (LIP) were significantly correlated with monthly incidence of CCHF in different lags (P < 0·05). The modelling fitness was checked with data from 2013. Model assessments indicated that the MSM had better predictive ability than the SARIMA model [MSM: root mean square error (RMSE) 0·625, Akaike's Information Criterion (AIC) 266·33; SARIMA: RMSE 0·725, AIC 278·8]. This study shows the potential of climate indicators and LIP as predictive factors in modelling the occurrence of CCHF. Our results suggest that MSM provides more information on outbreak detection and can be a better predictive model compared to a SARIMA model for evaluation of the relationship between explanatory variables and the incidence of CCHF.
The WTO and Regional Trade: a family business? The WTO compatibility of regional trade agreements with non-WTO-members
Authors: MOSSNER LOUISE EVA 
Published: May 2014

AbstractNumerous WTO members pursue regional economic integration with both other members and non-WTO-members. The resulting derogation from the most-favoured-nation principle needs to be justified in accordance with the relevant WTO provisions. Regional integration in the service sector is expressly allowed between WTO and non-WTO members pursuant to GATS Article V. In the absence of clear regulation, it has been questioned whether the same is true for regional trade agreements (RTAs) covering trade in goods. Providing a comprehensive interpretation, this paper argues that neither GATT Article XXIV nor the Enabling Clause require the WTO membership of all the parties to an RTA.
The monetization of global poverty: the concept of poverty in World Bank history, 1944–90
Authors: Konkel Rob 
Published: May 2014

AbstractThis article traces the history of the concept of poverty within the institutional framework of the World Bank, from its inception to its establishment of the dollar-a-day global poverty threshold. The Bank's evolving conceptualization of poverty and how it related to the development process affected the policies that were advanced to boost the productivity of underdeveloped countries. Internal and external influences and constraints conditioned the Bank's approach to poverty and its alleviation from the beginning, when poverty was conceived as a political issue beyond the scope of the Bank's mandate. Separating the political implications of poverty alleviation from the Bank's development agenda was tenuous, and by the 1970s a universal, absolute concept of poverty became the focal point of Bank operations. The eventual monetization of global poverty reflected the increasingly technical nature of the Bank's development work and its need for a practical yardstick by which to measure the success of its anti-poverty policies.
A global non-coding RNA system modulates fission yeast protein levels in response to stress
Authors: Leong Hui Sun , Dawson Keren , Wirth Chris , Li Yaoyong , Connolly Yvonne , Smith Duncan L. , Wilkinson Caroline R. M. , Miller Crispin J. 
Published: May 2014

AbstractNon-coding RNAs (ncRNAs) are frequent and prevalent across the taxa. Although individual non-coding loci have been assigned a function, most are uncharacterized. Their global biological significance is unproven and remains controversial. Here we investigate the role played by ncRNAs in the stress response of Schizosaccharomyces pombe. We integrate global proteomics and RNA sequencing data to identify a systematic programme in which elevated antisense RNA arising both from ncRNAs and from 3′-overlapping convergent gene pairs is directly associated with substantial reductions in protein levels throughout the genome. We describe an extensive array of ncRNAs with trans associations that have the potential to influence multiple pathways. Deletion of one such locus reduces levels of atf1, a transcription factor downstream of the stress-activated mitogen-activated protein kinase (MAPK) pathway, and alters sensitivity to oxidative stress. These non-coding transcripts therefore regulate specific stress responses, adding unanticipated information-processing capacity to the MAPK signalling system.
Filtering power divider with good isolation performance
Authors: Chao Shih‐Fong , Lin Wei‐Cheng 
Published: May 2014

A filtering power divider (PD) with good isolation performance is presented. The isolation performance is improved by introducing a distributed isolation network (DINW) to replace the conventional resistor isolation network. Moreover, the proposed DINW can be incorporated into a filter design to form a filtering PD. The filtering power divider was implemented at a centre frequency of 1 GHz with a fractional bandwidth of 56%, and the measured isolation is better than 23 dB across the entire operating band.
Four‐channel 60 GHz upconversion mixer with 14 dB gain and 2.5 dBm P1dB using transformer matching network
Authors: Chen Lin Hui , Li Lianming , Cui Tie Jun 
Published: May 2014

A 60 GHz upconversion mixer is realised in a 65 nm LP CMOS. The mixer consists of a Gilbert cell, a LO buffer and a RF buffer. To enhance the bandwidth and reduce the area, the transformer impedance matching network is used. The measured results show that the mixer covers the IEEE 802.15.3c standard four channels, from 57 to 66 GHz. In each channel, the gain flatness is <1.5 dB. In channel 2, the mixer achieves a gain of 14 dB and an output power 1 dB compression point of 2.5 dBm, while consuming 32 mW power drain from a 1 V supply. To the best of authors’ knowledge, this is an advance in the state‐of‐the‐art mixers.
Power‐efficient low‐noise 86 GHz broadband amplifier in 130 nm SiGe BiCMOS
Authors: Ding Ran , Xuan Zhe , Yao Peng , Baehr‐Jones T. , Prather D. , Hochberg M. 
Published: May 2014

A power‐efficient, low‐noise, broadband amplifier is demonstrated in a 130 nm SiGe BiCMOS process. The circuit exhibits a 20 dB gain, 86 GHz bandwidth and consumes only 89 mW DC power, achieving a gain‐bandwidth against DC power efficiency of 9.66 GHz/mW – a significant improvement over the prior art. Ultra‐high data rates (>80 Gbit/s) are supported owing to a low group delay variation of ±5.9 ps up to 100 GHz. Intended as a low‐noise transimpedance front‐end for optical receivers, the circuit exhibits a low average input‐referred‐noise of 20.4 pA/✓Hz, which is comparable to or better than the state‐of‐the‐art at much lower data rates.
Combined CSK and pulse position modulation scheme for indoor visible light communications
Authors: Luna‐Rivera J.M. , Perez‐Jimenez R. , Guerra‐Yañez V. , Suarez‐Rodriguez C. , Delgado‐Rajo F.A. 
Published: May 2014

The use of pulse‐coded signals over each colour component on a colour shift keying (CSK) modulation is explored. This codification improves the time‐synchronisation recovery capability on the IEEE 802.15.7 PHY III standard and reduces the overall system complexity. Different symbol codification rates are studied so as to improve the symbol error rate while minimising the effect over the throughput of the whole system.
The Semiotic Production of the Good Student: A Peircean Look at the Commodification of Liberal Arts Education
Authors: Urciuoli Bonnie 
Published: May 2014

AbstractLiberal arts education has become highly commodified, but what is the nature of the object commodified? I argue that that objectification is brought together through the branding process in the form of the Good Student, an unambiguously positive image of the product of higher education. Drawing from Peircian concepts and from recent works on branding as semiotic process, I show how college marketers produce this construction. I also argue that the Good Student is particularly suited to objectifying liberal arts education because of the peculiar qualities of liberal arts education: it does not train students for particular jobs, it is notoriously diffuse in academic content, and it is largely about class reproduction. The Good Student stands in as the ideal neoliberal middle-class product of such education: intelligent, flexible, self-controlled, productive, and socially safe.
Generation of induced pluripotent stem cell-derived mice by reprogramming of a mature NKT cell
Authors: Ren Yue , Dashtsoodol Nyambayar , Watarai Hiroshi , Koseki Haruhiko , Quan Chengshi , Taniguchi Masaru 
Published: May 2014

Abstract
NKT cells are characterized by their expression of an NKT-cell-specific invariant antigen-receptor α chain encoded by Vα14Jα18 gene segments. These NKT cells bridge the innate and acquired immune systems to mediate effective and augmented responses; however, the limited number of NKT cells in vivo hampers their analysis. Here, two lines of induced pluripotent stem cell-derived mice (NKT-iPSC-derived mice) were generated by reprogramming of mature NKT cells, where one harbors both rearranged Vα14Jα18 and Vβ7 genes and the other carries rearranged Vα14Jα18 on both alleles but germline Vβ loci. The analysis of NKT-iPSC-derived mice showed a significant increase in NKT cell numbers with relatively normal frequencies of functional subsets, but significantly enhanced in some cases, and acquired functional NKT cell maturation in peripheral lymphoid organs. NKT-iPSC-derived mice also showed normal development of other immune cells except for the absence of γδT cells and disturbed development of conventional CD4 αβT cells. These results suggest that the NKT-iPSC-derived mice are a better model for NKT cell development and function study rather than transgenic mouse models reported previously and also that the presence of a pre-rearranged Vα14Jα18 in the natural chromosomal context favors the developmental fate of NKT cells.
De novo detection of differentially bound regions for ChIP-seq data using peaks and windows: controlling error rates correctly
Authors: Lun Aaron T.L. , Smyth Gordon K. 
Published: May 2014

AbstractA common aim in ChIP-seq experiments is to identify changes in protein binding patterns between conditions, i.e. differential binding. A number of peak- and window-based strategies have been developed to detect differential binding when the regions of interest are not known in advance. However, careful consideration of error control is needed when applying these methods. Peak-based approaches use the same data set to define peaks and to detect differential binding. Done improperly, this can result in loss of type I error control. For window-based methods, controlling the false discovery rate over all detected windows does not guarantee control across all detected regions. Misinterpreting the former as the latter can result in unexpected liberalness. Here, several solutions are presented to maintain error control for these de novo counting strategies. For peak-based methods, peak calling should be performed on pooled libraries prior to the statistical analysis. For window-based methods, a hybrid approach using Simes’ method is proposed to maintain control of the false discovery rate across regions. More generally, the relative advantages of peak- and window-based strategies are explored using a range of simulated and real data sets. Implementations of both strategies also compare favourably to existing programs for differential binding analyses.
Properties of intrinsic polarization angle ambiguities in Faraday tomography
Authors: Kumazaki Kohei , Akahori Takuya , Ideguchi Shinsuke , Kurayama Tomoharu , Takahashi Keitaro 
Published: May 2014

Abstract
Faraday tomography is a powerful method to diagnose polarizations and Faraday rotations along the line of sight. The quality of Faraday tomography is, however, limited by several conditions. Recently, it is reported that Faraday tomography indicates false signals in some specific situations. In this paper, we systematically investigate the condition of the appearance of false signals in Faraday tomography. We study this by pseudo-observing two sources within a beam, and change in the intrinsic polarization angles, rotation measures, intensities, and frequency coverage. We find that false signals arise when the rotation measure between the sources is less than 1.5 times the full width at half maximum of the rotation measure spread function. False signals also depend on the intensity ratio between the sources and are reduced for large ratios. On the other hand, the appearance of false signals does not depend on frequency coverage, meaning that the uncertainty should be correctly understood and taken into consideration, even with future wide-band observations such as the Square Kilometer Array (SKA).
Reservoir monitoring of steam‐assisted gravity drainage using borehole measurements
Authors: Tøndel Richard , Schütt Hartmut , Dümmong Stefan , Ducrocq Alexandre , Godfrey Robert , LaBrecque Douglas , Nutt Les , Campbell Allan , Rufino Rogelio 
Published: May 2014

ABSTRACTThis paper presents the results from a research project focusing on permanent cross‐well geophysical methods for reservoir monitoring during steam‐assisted gravity drainage. A feasibility study indicated detectable differences in seismic and electrical reservoir properties based on expected changes in temperature and fluid saturation during the production of extra heavy oil. As a result of this, a permanent cross‐well system was installed at the Leismer Demonstration Area, located in the Athabasca Oil Sands region in Alberta, Canada. Baseline data sets, including cross‐well seismic, three‐dimensional vertical seismic profiling and cross‐well electrical resistivity tomography, have been acquired. Comparisons between conventional surface seismic and downhole seismic data show an increase in resolution and frequency content as expected. Steam‐assisted gravity drainage‐induced time‐lapse effects are clearly visible in the 3D vertical seismic profiling and electrical resistivity tomography data sets, even after a few months of oil production. In general, the 3D vertical seismic profiling images show a higher resolution than the surface seismic data, in particular when dealing with vertical positioning of the time‐lapse events. The electrical resistivity tomography baseline shows clear separation between zones of high and low electrical resistivity, and during 23 months of electrical resistivity tomography measurements the maximum reduction of resistivity is 85%. Time‐lapse observations from acoustic and electrical borehole data correspond well, and are also supported by temperature measurements in the two observation wells. Emerging technologies, updated models, improved flexibility, and reduced costs will allow future reservoir monitoring with surface and borehole data in combination, or even with borehole data exclusively.
Characterization of chitinase‐producing Serratia and Bacillus strains isolated from insects
Authors: Han Kook‐Il , Patnaik Bharat Bhusan , Cho Ah‐ra , Lim Ho Kab , Lee Jae Min , Jang Young Geun , Jeong Yun Seon , Yoo Tae Kyeong , Lee Gyeong Seok , Han Man‐Deuk 
Published: May 2014

AbstractChitinases (EC 3.2.1.14) are enzymes that hydrolyze chitin by cleaving β‐1,4 N‐glycosidic bonds. These enzymes have been used for multiple applications in biotechnology, especially for controlling insect pests and phytopathogenic fungi. In the present study, we isolated two chitinase‐producing bacteria strains from insects (strain SCH‐1 from Moechotypa diphysis and strain SCH‐2 from Sphedanolestes impressicollis). Serratia sp. SCH‐1 was a short, rod‐shaped facultative anaerobe, while Bacillus strain SCH‐2 was a rod‐shaped endospore‐forming anaerobe. Strains SCH‐1 and SCH‐2 were identified as Serratia sp. and Bacillus sp., respectively based on 16S rRNA gene sequencing. Strain SCH‐1 shared maximum homology (99.44%) with Serratia nematodiphila DZ0503SBS1 and Serratia marcescens subsp. sakuensis KRED. Strain SCH‐2 had a maximum homology of 99.24% with Bacillus thuringiensis ATCC 10792 and Bacillus toyonensis BCT‐7112. Serratia sp. SCH‐1 contained greater levels of saturated fatty acids, but the concentration of branched acids, especially iso‐C15:0, was highest in Bacillus sp. SCH‐2. Serratia sp. SCH‐1 possessed chitinase activity of 1.59 unit/mg protein after 5 days of incubation in culture medium. In contrast, Bacillus sp. SCH‐2 had a maximum activity of 0.84 unit/mg protein after 4 days of incubation. Chitinase isozymes produced by Serratia sp. SCH‐1 appeared as five bands with sizes of 20, 26, 36, 45 and 54 kDa. Bacillus sp. SCH‐2 showed a chitinase isozyme profile with three bands having sizes of 36, 45 and 50 kDa on SDS‐PAGE gels.
Temporal Variation in Soluble Human Leukocyte Antigen‐G (sHLA‐G) and Pregnancy‐Associated Plasma Protein A (PAPP‐A) in Pregnancies Complicated by Gestational Diabetes Mellitus and in Controls
Authors: Beneventi Fausta , Simonetta Margherita , Locatelli Elena , Cavagnoli Chiara , Badulli Carla , Lovati Elisabetta , Garbin Giulia , Genini Emilia , Albertini Riccardo , Tinelli Carmine , Martinetti Miryam , Spinillo Arsenio 
Published: May 2014

ProblemTo target gestational diabetes mellitus (GDM) by means of temporal variation in pregnancy‐associated plasma protein A (PAPP‐A) and soluble human leukocyte antigen‐G (sHLA‐G).Method of studyRetrospective analysis of PAPP‐A and sHLA‐G blood levels in historical samples of 112 GDM and 112 controls, drawn at first trimester, and prospective study in 18 GDM and 105 controls collected in triplicate along the pregnancy. Six hundred and sixty‐five samples were analyzed.ResultsGestational diabetes mellitus had significantly lower first‐trimester PAPP‐A concentrations than controls (2343 ± 1519 versus 2996 ± 1955 mU/mL, in retrospective brunch and 2490.57 ± 1828.52 versus 3240.84 ± 1930.69 mU/L in prospective one, P < 0.001). First‐trimester sHLA‐G level was significantly lower in GDM than in controls (52.88 ± 59.69 versus 66.81 ± 50.14 ng/mL, P < 0.001) and increased during gestation in diabetic women showing an opposite trend with respect to the controls.ConclusionPAPP‐A and sHLA‐G are independent markers of GDM. Quantitative variations during pregnancy help to early unravel the onset of GDM.