bluuebunny/crossref_metadata_2025_split huggingface dataset:
Networked LQG control over unreliable channels
Authors: Moayedi M. , Foo Y.K. , Soh Y.C. 
Published: November 2011

SUMMARYIn this article, the linear quadratic Gaussian (LQG) optimal control problem for networked control systems when data is transmitted through a transmission control protocol (TCP)‐like network and both measurement and control packets are subject to random packet dropouts, is addressed for two cases. In the ﬁrst case, it is assumed that the control acknowledgment packets in TCP‐like protocols are always available, that is, they always reach the ﬁlter‐controller unit on time and without fail, and we propose how to design a linear optimal ‘hold‐input’ control law for this case. In the second problem, we assume the acknowledgement packets may go missing with a known probability. This case is known to be diﬃcult and the optimal control law would be nonlinear. Hence, we derive a suboptimal linear estimation‐control law instead. Simulation results are presented to demonstrate the effectiveness of the proposed approaches. Copyright © 2011 John Wiley & Sons, Ltd.
Consistency in explaining model behavior based on its feedback structure
Authors: Mojtahedzadeh Mohammad 
Published: November 2011

AbstractReal‐world concepts can be operationalized into a variety of feedback structures which may be mathematically identical but diverse in the number of feedback loops. Factors including model purpose, the modeler's perspective and the intended audience all influence the final layout of a feedback‐rich model. One challenge in the analysis of model behavior is to account for the variations in the appearance of its structure and the feedback loops. This technical paper focuses on consistency in explaining model behavior and illustrates some of the issues related to the cancellation problem and figure‐8 loops. Both conditions can potentially lead to poor and even contradictory explanations of model behavior based on its idiosyncratic feedback structure. The paper presents three case studies and demonstrates that for these case studies the pathway participation approach remains consistent in detecting the dominant structure regardless of variations in the number of feedback loops in mathematically equivalent models. The paper calls for comparative studies using alternative approaches to model analysis to better understand the general principles and subtleties in connecting the structure to the behavior and explaining observed dynamics. Copyright © 2011 System Dynamics Society.
The impact of current and founding institutions on strength of competitive aspirations in transition economies
Authors: Shinkle George A. , Kriauciunas Aldas P. 
Published: November 2011

AbstractNorthian institutional theory argues that firms adapt to their current institutional environments. Organizational imprinting theory argues that firms will be constrained by their founding institutional environments. We explore the combined influence of these two institutional environments on the strength of competitive aspirations using a unique dataset of firms in the shifted institutional environment of Central European transition economies. Our results indicate founding institutional environments temper adaptation to current institutional environments for certain competitive aspirations and this effect increases as the size of the shift between current and founding institutional environments increases. Copyright © 2011 John Wiley & Sons, Ltd.
Nitric Oxide Sustains Long-Term Skeletal Muscle Regeneration by Regulating Fate of Satellite Cells Via Signaling Pathways Requiring Vangl2 and Cyclic GMP
Authors: Buono Roberta , Vantaggiato Chiara , Pisa Viviana , Azzoni Emanuele , Bassi Maria Teresa , Brunelli Silvia , Sciorati Clara , Clementi Emilio 
Published: November 2011

AbstractSatellite cells are myogenic precursors that proliferate, activate, and differentiate on muscle injury to sustain the regenerative capacity of adult skeletal muscle; in this process, they self-renew through the return to quiescence of the cycling progeny. This mechanism, while efficient in physiological conditions does not prevent exhaustion of satellite cells in pathologies such as muscular dystrophy where numerous rounds of damage occur. Here, we describe a key role of nitric oxide, an important signaling molecule in adult skeletal muscle, on satellite cells maintenance, studied ex vivo on isolated myofibers and in vivo using the α-sarcoglycan null mouse model of dystrophy and a cardiotoxin-induced model of repetitive damage. Nitric oxide stimulated satellite cells proliferation in a pathway dependent on cGMP generation. Furthermore, it increased the number of Pax7+/Myf5− cells in a cGMP-independent pathway requiring enhanced expression of Vangl2, a member of the planar cell polarity pathway involved in the Wnt noncanonical pathway. The enhanced self-renewal ability of satellite cells induced by nitric oxide is sufficient to delay the reduction of the satellite cell pool during repetitive acute and chronic damages, favoring muscle regeneration; in the α-sarcoglycan null dystrophic mouse, it also slowed disease progression persistently. These results identify nitric oxide as a key messenger in satellite cells maintenance, expand the significance of the Vangl2-dependent Wnt noncanonical pathway in myogenesis, and indicate novel strategies to optimize nitric oxide-based therapies for muscular dystrophy.Disclosure of potential conflicts of interest is found at the end of this article.
The Crosstalk Between Transforming Growth Factor-β1 and Delta Like-1 Mediates Early Chondrogenesis During Embryonic Endochondral Ossification
Authors: Taipaleenmäki Hanna , Harkness Linda , Chen Li , Larsen Kenneth H. , Säämänen Anna-Marja , Kassem Moustapha , Abdallah Basem M. 
Published: November 2011

Abstract
Delta like-1 (Dlk1)/preadipocyte factor-1 (Pref-1)/fetal antigen-1 (FA1) is a novel surface marker for embryonic chondroprogenitor cells undergoing lineage progression from proliferation to prehypertrophic stages. However, mechanisms mediating control of its expression during chondrogenesis are not known. Thus, we examined the effect of a number of signaling molecules and their inhibitors on Dlk1 expression during in vitro chondrogenic differentiation in mouse embryonic limb bud mesenchymal micromass cultures and mouse embryonic fibroblast (MEF) pellet cultures. Dlk1/Pref-1 was initially expressed during mesenchymal condensation and chondrocyte proliferation, in parallel with expression of Sox9 and Col2a1, and was downregulated upon the expression of Col10a1 by hypertrophic chondrocytes. Among a number of molecules that affected chondrogenesis, transforming growth factor-β1 (TGF-β1)-induced proliferation of chondroprogenitors was associated with decreased Dlk1 expression. This effect was abolished by TGF-β signaling inhibitor SB431542, suggesting regulation of Dlk1/FA1 by TGF-β1 signaling in chondrogenesis. TGF-β1-induced Smad phosphorylation and chondrogenesis were significantly increased in Dlk1−/− MEF, while they were blocked in Dlk1 overexpressing MEF, in comparison with wild-type MEF. Furthermore, overexpression of Dlk1 or addition of its secreted form FA1 dramatically inhibited TGF-β1-induced Smad reporter activity. In conclusion, our data identified Dlk1/FA1 as a downstream target of TGF-β1 signaling molecule that mediates its function in embryonic chondrogenesis. The crosstalk between TGF-β1 and Dlk1/FA1 was shown to promote early chondrogenesis during the embryonic endochondral ossification process.
Disclosure of potential conflicts of interest is found at the end of this article.
Pathfinding in angiosperm reproduction: pollen tube guidance by pistils ensures successful double fertilization
Authors: Palanivelu Ravishankar , Tsukamoto Tatsuya 
Published: November 2011

AbstractSexual reproduction in flowering plants is unique in multiple ways. Distinct multicellular gametophytes contain either a pair of immotile, haploid male gametes (sperm cells) or a pair of female gametes (haploid egg cell and homodiploid central cell). After pollination, the pollen tube, a cellular extension of the male gametophyte, transports both male gametes at its growing tip and delivers them to the female gametes to affect double fertilization. The pollen tube travels a long path and sustains its growth over a considerable amount of time in the female reproductive organ (pistil) before it reaches the ovule, which houses the female gametophyte. The pistil facilitates the pollen tube's journey by providing multiple, stage‐specific, nutritional, and guidance cues along its path. The pollen tube interacts with seven different pistil cell types prior to completing its journey. Consequently, the pollen tube has a dynamic gene expression program allowing it to continuously reset and be receptive to multiple pistil signals as it migrates through the pistil. Here, we review the studies, including several significant recent advances, that led to a better understanding of the multitude of cues generated by the pistil tissues to assist the pollen tube in delivering the sperm cells to the female gametophyte. We also highlight the outstanding questions, draw attention to opportunities created by recent advances and point to approaches that could be undertaken to unravel the molecular mechanisms underlying pollen tube–pistil interactions. WIREs Dev Biol 2012, 1:96–113. doi: 10.1002/wdev.6This article is categorized under:

Plant Development > Gametophyte Development
Plant Development > Fertilization, Embryogenesis, and Seed Development
Plant Development > Inflorescence, Flower, and Fruit Development
Additional Supporting Information may be found in the online version of this article.Movie1‐Palanivelu‐Tsukamoto.movMovie1‐Palanivelu‐Tsukamoto.mov
Birds of an ethnic feather? Ethnic identity homophily among college‐age friends
Authors: Syed Moin , Juan Mary Joyce D. 
Published: November 2011

ABSTRACTThis study assessed the degree to which pairs of friends report similar levels of ethnic identity. College‐age friends (n= 107 pairs;N= 214 overall) completed measures of ethnic identity exploration and commitment, identity synthesis, relationship closeness, and frequency of talking to friends and family about ethnicity‐related issues. Participants were ethnically‐diverse and constituted three types of dyads: both ethnic minorities (n= 51), both White (n= 24), or mixed ethnic minority and White (n= 32). Overall, friends reported similar levels of ethnic identity exploration and commitment. The ethnic composition of the pair moderated similarity, with ethnic minority pairs showing greater similarity than the White and mixed pairs. Frequency of ethnicity‐related discussions with friends and family, but not relationship closeness, mediated the observed similarity for ethnic minority pairs. These findings suggest a level of ethnic identity homophily between ethnic minority friends that can be explained by interactional mechanisms.
Bursting bubble aerosols
Authors: Lhuissier H. , Villermaux E. 
Published: November 2011

AbstractWe depict and analyse the complete evolution of an air bubble formed in a water bulk, from the time it emerges at the liquid surface, up to its fragmentation into dispersed drops. To this end, experiments describing the drainage of the bubble cap film, its puncture and the resulting bursting dynamics determining the aerosol formation are conducted on tapwater bubbles. We discover that the mechanism of marginal pinching at the bubble foot and associated convection motions in the bubble cap, known as marginal regeneration, both drive the bubble cap drainage rate, and are responsible for its puncture. The resulting original film thickness $h$ evolution law in time, supplemented with considerations about the nucleation of holes piercing the film together culminate in a determination of the cap film thickness at bursting ${h}_{b} \propto {R}^{2} / \mathscr{L}$, where $R$ is the bubble cap radius of curvature, and $\mathscr{L}$ a length which we determine. Subsequent to a hole nucleation event, the cap bursting dynamics conditions the resulting spray. The latter depends both on the bubble shape prescribed by $R/ a$, where $a$ is the capillary length based on gravity, and on ${h}_{b} $. The mean drop size $\langle d\rangle \ensuremath{\sim} {R}^{3/ 8} \hspace{0.167em} { h}_{b}^{5/ 8} $, the number of drops generated per bubble $N\ensuremath{\sim} \mathop{ (R/ a)}\nolimits ^{2} \mathop{ (R/ {h}_{b} )}\nolimits ^{7/ 8} $ and the drop size distribution $P(d)$ are derived, comparing well with measurements. Combined with known bubble production rates over the ocean, our findings offer an adjustable parameter-free prediction for the aerosol flux and spray structure caused by bubble bursting in this precise context.
Effect of intensive counselling on the quality of dietary fats in pregnant women at high risk of gestational diabetes mellitus
Authors: Korpi-Hyövälti Eeva , Schwab Ursula , Laaksonen David E. , Linjama Hilpi , Heinonen Seppo , Niskanen Leo 
Published: November 2011

As part of a feasibility study to prevent gestational diabetes mellitus (GDM), we evaluated the effect of an intensive dietary therapy on quality of diet, weight gain and birth weight in women at high risk of GDM. Women with risk factors for GDM (n 54) were randomly assigned from April 2005 to May 2006 to a lifestyle intervention group (n 27) including dietary advice six times during pregnancy or to a close follow-up group (n 27) in a community-based setting in Finland. Dietary intake was recorded three times during pregnancy using 4 d food records. The main outcome was the incidence of GDM. The secondary outcomes were the changes in nutrient intake, weight gain and birth weight. Overall, seventeen (65 %) women in the intervention group and eighteen (69 %) women in the close follow-up group returned all three food records. PUFA intake increased (P = 0·008) during pregnancy in the intervention as compared to the close follow-up group. There were no clear differences in the changes of saturated fat or fibre intake between the groups. Intensive dietary education resulted in a somewhat lower weight gain during pregnancy (P = 0·062) and higher birth weights of the infants (P = 0·047) without an effect on macrosomia as compared to the close follow-up group. Individualised counselling by a clinical nutritionist as part of a lifestyle intervention improved the quality of dietary fat intake in pregnant women at high risk of GDM.
Space-resolved characterization of high frequency atmospheric-pressure plasma in nitrogen, applying optical emission spectroscopy and numerical simulation
Authors: Rajasekaran Priyadarshini , Ruhrmann Cornelia , Bibinov Nikita , Awakowicz Peter 
Published: November 2011

Abstract

Averaged plasma parameters such as electron distribution function and electron density are determined by characterization of high frequency (2.4 GHz) nitrogen plasma using both experimental methods, namely optical emission spectroscopy (OES) and microphotography, and numerical simulation. Both direct and step-wise electron-impact excitation of nitrogen emissions are considered. The determination of space-resolved electron distribution function, electron density, rate constant for electron-impact dissociation of nitrogen molecule and the production of nitrogen atoms, applying the same methods, is discussed. Spatial distribution of intensities of neutral nitrogen molecule and nitrogen molecular ion from the microplasma is imaged by a CCD camera. The CCD images are calibrated using the corresponding emissions measured by absolutely calibrated OES, and are then subjected to inverse Abel transformation to determine space-resolved intensities and other parameters. The space-resolved parameters are compared, respectively, with the averaged parameters, and an agreement between them is established.
On the role of Fe2+ in the luminescence of feldspar: an exploration of Fe2+/Fe3+ L-edge near edge x-ray absorption fine structure using comparative electronic and optical detection methods
Authors: Poolton N R J , Kirkman I W , Pantos E 
Published: November 2011

Abstract
The luminescence properties of Fe3+ defects in feldspar are well know, but the role played by Fe2+ centres remains ambiguous, with tentative previous evidence suggesting it could act as a luminescence activator, luminescence quencher, or neither one nor the other: the outcome of these arguments would be of direct and topical relevance to consideration of using Fe3+ luminescence for the in situ dating of Martian sediments in future probe missions to the planet. Therefore, to elucidate the relative roles of Fe2+ and Fe3+, a synchrotron radiation study of Fe2+/Fe3+ defects in feldspar has been undertaken by probing the L-edges of the ion. Partial electron yield results allow a measure of the relative proportion of the ion states to be made, but of itself provides no indication of the defect's optical activity: in order to determine the latter, optical detection of x-ray absorption spectroscopy has been deployed. Although minor differences in the Fe2+/Fe3+ ratios are established using the two measurement methods, the results of the survey indicate that Fe2+ is unlikely to be an efficient luminescence quenching centre, and that competition for charge between the ion in its 2+/3+ states is not radically different. Equally, no evidence was found to suggest that it efficiently contributes to the visible emission in the range 380–750 nm.
rNA: a fast and accurate short reads numerical aligner
Authors: Vezzi Francesco , Del Fabbro Cristian , Tomescu Alexandru I. , Policriti Alberto 
Published: November 2011

Abstract
Summary: The advent of high-throughput sequencers (HTS) introduced the need of new tools in order to analyse the large amount of data that those machines are able to produce. The mandatory first step for a wide range of analyses is the alignment of the sequences against a reference genome. We present a major update to our rNA (randomized Numerical Aligner) tool. The main feature of rNA is the fact that it achieves an accuracy greater than the majority of other tools in a feasible amount of time. rNA executables and source codes are freely downloadable at http://iga-rna.sourceforge.net/.
Contact: vezzi@appliedgenomics.org; delfabbro@appliedgenomics.org
Supplementary information: Supplementary data are available at Bioinformatics online.
MYB8 Controls Inducible Phenolamide Levels by Activating Three Novel Hydroxycinnamoyl-Coenzyme A:Polyamine Transferases in Nicotiana attenuata
Authors: Onkokesung Nawaporn , Gaquerel Emmanuel , Kotkar Hemlata , Kaur Harleen , Baldwin Ian T. , Galis Ivan 
Published: November 2011

Abstract
A large number of plants accumulate N-acylated polyamines (phenolamides [PAs]) in response to biotic and/or abiotic stress conditions. In the native tobacco (Nicotiana attenuata), the accumulation of two major PAs, caffeoylputrescine and dicaffeoylspermidine (DCS), after herbivore attack is known to be controlled by a key transcription factor, MYB8. Using a broadly targeted metabolomics approach, we show that a much larger spectrum of PAs composed of hydroxycinnamic acids and two polyamines, putrescine and spermidine, is regulated by this transcription factor. We cloned several novel MYB8-regulated genes, annotated as putative acyltransferases, and analyzed their function. One of the novel acyltransferases (AT1) is shown to encode a hydroxycinnamoyl-coenzyme A:putrescine acyltransferase responsible for caffeoylputrescine biosynthesis in tobacco. Another gene (acyltransferase DH29), specific for spermidine conjugation, mediates the initial acylation step in DCS formation. Although this enzyme was not able to perform the second acylation toward DCS biosynthesis, another acyltransferase gene, CV86, proposed to act on monoacylated spermidines, was isolated and partially characterized. The activation of MYB8 in response to herbivore attack and associated signals required the activity of LIPOXYGENASE3, a gene involved in jasmonic acid (JA) biosynthesis in N. attenuata. These new results allow us to reconstruct a complete branch in JA signaling that defends N. attenuata plants against herbivores: JA via MYB8’s transcriptional control of AT1 and DH29 genes controls the entire branch of PA biosynthesis, which allows N. attenuata to mount a chemically diverse (and likely efficient) defense shield against herbivores.
CO2-cAMP-Responsive cis-Elements Targeted by a Transcription Factor with CREB/ATF-Like Basic Zipper Domain in the Marine Diatom Phaeodactylum tricornutum
Authors: Ohno Naoki , Inoue Takuya , Yamashiki Ryosuke , Nakajima Kensuke , Kitahara Yuhei , Ishibashi Mikiko , Matsuda Yusuke 
Published: November 2011

Abstract
Expression controls of the carbon acquisition system in marine diatoms in response to environmental factors are an essential issue to understand the changes in marine primary productivity. A pyrenoidal β-carbonic anhydrase, PtCA1, is one of the most important candidates to investigate the control mechanisms of the CO2 acquisition system in the marine diatom Phaeodactylum tricornutum. A detailed functional assay was carried out on the putative core regulatory region of the ptca1 promoter using a β-glucuronidase reporter in P. tricornutum cells under changing CO2 conditions. A set of loss-of-function assays led to the identification of three CO2-responsive elements, TGACGT, ACGTCA, and TGACGC, at a region −86 to −42 relative to the transcription start site. Treatment with a cyclic (c)AMP analog, dibutyryl cAMP, revealed these three elements to be under the control of cAMP; thus, we designated them, from 5′ to 3′, as CO2-cAMP-Responsive Element1 (CCRE1), CCRE2, and CCRE3. Because the sequence TGACGT is known to be a typical target of human Activating Transcription Factor6 (ATF6), we searched for genes containing a basic zipper (bZIP) region homologous to that of ATF6 in the genome of P. tricornutum. Gel-shift assays using CCRE pentamers as labeled probes showed that at least one candidate of bZIP proteins, PtbZIP11, bound specifically to CCREs. A series of gain-of-function assays with CCREs fused to a minimal promoter strongly suggested that the alternative combination of CCRE1/2 or CCRE2/3 at proper distances from the minimal promoter is required as a potential target of PtbZIP11 for an effective CO2 response of the ptca1 gene.
Temsirolimus, an mTOR inhibitor, in combination with lower‐dose clofarabine as salvage therapy for older patients with acute myeloid leukaemia: results of a phase II GIMEMA study (AML‐1107)
Authors: Amadori Sergio , Stasi Roberto , Martelli Alberto M. , Venditti Adriano , Meloni Giovanna , Pane Fabrizio , Martinelli Giovanni , Lunghi Monia , Pagano Livio , Cilloni Daniela , Rossetti Elena , Di Raimondo Francesco , Fozza Claudio , Annino Luciana , Chiarini Francesca , Ricci Francesca , Ammatuna Emanuele , La Sala Edoardo , Fazi Paola , Vignetti Marco 
Published: November 2011

SummaryThe mammalian target of rapamycin (mTOR) signalling pathway has emerged as an important therapeutic target for acute myeloid leukaemia (AML). This study assessed the combination of temsirolimus, an mTOR inhibitor, and lower‐dose clofarabine as salvage therapy in older patients with AML. Induction consisted of clofarabine 20 mg/m2 on days 1–5 and temsirolimus 25 mg (flat dose) on days 1, 8 and 15. Patients achieving complete remission with (CR) or without (CRi) full haematological recovery could receive monthly temsirolimus maintenance. In 53 evaluable patients, the overall remission rate (ORR) was 21% (8% CR, 13% CRi). Median disease‐free survival was 3·5 months, and median overall survival was 4 months (9·1 months for responders). The most common non‐haematological severe adverse events included infection (48%), febrile neutropenia (34%) and transaminitis (11%). The 30‐d all‐cause induction mortality was 13%. Laboratory data from 25 patients demonstrated that a >50%in vivo inhibition of S6 ribosomal protein phosphorylation was highly correlated with response rate (75% with inhibition versus 0% without inhibition; P = 0·0001), suggesting that targeting the mTOR pathway is clinically relevant. The acceptable safety profile and the predictive value of target inhibition encourage further investigation of this novel regimen.