bluuebunny/crossref_metadata_2025 huggingface dataset:
The US launch of Al Jazeera English in Washington, DC: An analysis of American media coverage
Authors: Meltzer Kimberly
Published: June 2012

Since its US launch in the Washington, DC, market in July 2009, Al Jazeera English (AJE), like other news organizations, has engaged in activities to shape and promote its journalistic values and practices for itself and the public. Using the theoretical framework of journalists as interpretive communities, this article examines American media coverage of AJE through its first seven months of broadcasting in the DC market. The study finds that AJE’s attempts to shape and modify its image for an American audience have been mostly successful, although limited. The analysis indicates a gradual move towards acceptance of the network in the USA by its journalistic peers (other American journalists).
Does Maltreatment Beget Maltreatment? A Systematic Review of the Intergenerational Literature
Authors: Thornberry Terence P. , Knight Kelly E. , Lovegrove Peter J.
Published: June 2012

In this article, the authors critically review the literature testing the cycle of maltreatment hypothesis which posits continuity in maltreatment across adjacent generations. That is, the authors examine whether a history of maltreatment victimization is a significant risk factor for the later perpetration of maltreatment. The authors begin by establishing 11 methodological criteria that studies testing this hypothesis should meet. They include such basic standards as using representative samples, valid and reliable measures, prospective designs, and different reporters for each generation. The authors identify 47 studies that investigated this issue and then evaluate them with regard to the 11 methodological criteria. Overall, most of these studies report findings consistent with the cycle of maltreatment hypothesis. Unfortunately, at the same time, few of them satisfy the basic methodological criteria that the authors established; indeed, even the stronger studies in this area only meet about half of them. Moreover, the methodologically stronger studies present mixed support for the hypothesis. As a result, the positive association often reported in the literature appears to be based largely on the methodologically weaker designs. Based on this systematic methodological review, the authors conclude that this small and methodologically weak body of literature does not provide a definitive test of the cycle of maltreatment hypothesis. The authors conclude that it is imperative to develop more robust and methodologically adequate assessments of this hypothesis to more accurately inform the development of prevention and treatment programs.
Hobbies and Vices, Book Lovers and Nerds
Authors: Alasuutari Pertti , Luomanen Jari , Peteri Virve
Published: June 2012

By drawing on eighty-nine qualitative interviews in which people account for their use of information and communication technology, this article analyzes how people negotiate their choices and principles in relation to prevalent discourses about proper and questionable conduct and content and whether old discourses are changing in the new media environment. Particular attention is paid to the way in which the cultural category of hobby is used as a speech repertoire that ennobles internet use. By describing their complementary use of different media and the meanings of different artifacts, informants are able to reverse default cultural hierarchies.
Management of Central Venous Gradient Using Excimer Laser Lead Extraction of Chronic Indwelling Pacemaker Leads in the Setting of Ipsilateral Arteriovenous Fistula
Authors: Ramirez Alexies , Gentlesk Philip J. , Peele Mark E. , Eckart Robert E.
Published: June 2012

Device therapy is becoming common in those patients with renal insufficiency. Coexisting need for arteriovenous (AV) fistula placement is often contemplated relative to device placement. We describe the excimer laser lead extraction of a malfunctioning chronic atrial pacemaker lead ipsilateral to an AV fistula.
Modeling and prediction of subject accrual and event times in clinical trials: a systematic review
Authors: Zhang Xiaoxi , Long Qi
Published: June 2012

Background

Modeling and prediction of subject accrual and event times in clinical trials has been a topic of considerable interest for important practical reasons. It has implications not only at the initial planning stage of a trial but also on its ongoing monitoring.

Purpose

To provide a systematic view of the recent research in the field of modeling and prediction of subject accrual and event times in clinical trials.

Methods

Two classes of methods for modeling and prediction of subject accrual are reviewed, namely, one that uses the Brownian motion and the other uses the Poisson process. Extensions of the accrual models in multicenter clinical trials are also discussed. Trials with survival endpoints require proper joint modeling of subject accrual and event/lost-to-follow-up (LTFU) times, the latter of which can be modeled either parametrically (e.g., exponential and Weibull) or nonparametrically.

Results

Flexible stochastic models are better suited when modeling real trials that does not follow constant underlying enrollment rate. The accrual model generally improves as center-specific information is accounted for in multicenter trials. The choice between parametric and nonparametric event models can depend on confidence on the underlying event rates.

Limitations

All methods reviewed in event modeling assume noninformative censoring, which cannot be tested.

Conclusions

We recommend using proper stochastic accrual models, in combination with flexible event time models when applicable, for modeling and prediction of subject enrollment and event times in clinical trials.
Collaborative efforts: An exploratory study of citizen media in China
Authors: Guo Lei
Published: June 2012

In the field of citizen media research, considerably less attention has been paid to countries other than the US and those in Western Europe. This article is a case study that focuses on citizen media in Beijing – specifically, the Dazhalan Project. Combining in-depth interviews and textual analysis, the article demonstrates the uniqueness of citizen media under China’s state-party media system. The article also suggests that it was the collaboration among ordinary citizens, professionals and journalists that made it possible for citizen media to influence the mainstream media frame-building process.
Strategies for the Implementation of Service Innovations
Authors: Enz Cathy A.
Published: June 2012

Implementation strategies are the ways in which information about a new service innovation are shared with those employees who must execute on the innovation. This article examines the relationship between innovation success and the frequency of use of various strategies for the implementation of two specific nationwide service innovations in the North American hotels of a global lodging chain. Cost and service quality–based innovations were found to rely on different implementation strategies, suggesting that the connection between an implementation strategy and success depends on the type of innovation. In the hotel chain studied, the most successful strategy for implementing quality innovations was individual counseling, while rewards and focus groups were most strongly associated with success when implementing cost-based innovations. A mix of execution strategies including implementation by persuasion, leader intervention, participation, and even edict were linked to service innovation success. Participative employee-centered implementation strategies emerged as the most critical in the diffusion of service innovations.
From bad to worse
Authors: Groth Markus , Grandey Alicia
Published: June 2012

Poor employee–customer interactions influence customer satisfaction and employee well-being. In studying these negative exchanges, researchers tend to take either the perspective of the customer (i.e., the problem is service failure) or the employee (i.e., the problem is the difficult customer). We review these two literatures to show that the inputs, processes, and outcomes of these two perspectives are linked in a way that creates a negative exchange spiral. We argue that this is an “open-loop” spiral because the negative service encounter spills over to the experience of subsequent customers and nearby employees. We suggest that future research use an integrated model of the employee–customer negative exchange spiral and dyadic methods to more effectively test and understand these negative exchanges. Finally, we propose how dyadic and contextual characteristics accelerate or break the negative spiral, suggesting research and practical implications.
Depression, Access Barriers, and Their Combined Associations with Unmet Health Needs among Publicly Insured Individuals in Minnesota
Authors: Shippee Nathan D. , Call Kathleen Thiede , Weber Whitney , Beebe Timothy J.
Published: June 2012

Studies have examined how individual risk factors affect unmet health needs, but few have assessed how factors combine to create compounded risk. Using administrative and survey data from 1,897 publicly insured individuals in Minnesota, this study examines how diagnosed depression—a condition with established functional morbidity—moderates the association between seven common access barriers (e.g., transportation problems, lack of child care, clinic hours) and self-reported unmet health needs. Depression and access barriers were independently, positively associated with unmet need. Depression moderated barriers’ effects: Number of barriers reported had a stronger association with unmet need for individuals with depression. Depressed individuals reporting all barriers had a 70 percent chance of unmet need. Subgroup differences for individual barriers suggest that depressed individuals’ utilization patterns and functional limitations may shape their reactions to access barriers. Findings may inform improvements in public benefit designs and target the unique vulnerabilities associated with depression.
C-C motif chemokine CCL3 and canonical neutrophil attractants promote neutrophil extravasation through common and distinct mechanisms
Authors: Reichel Christoph A. , Puhr-Westerheide Daniel , Zuchtriegel Gabriele , Uhl Bernd , Berberich Nina , Zahler Stefan , Wymann Matthias P. , Luckow Bruno , Krombach Fritz
Published: June 2012

Initial observations suggested that C-C motif chemokines exclusively mediate chemotaxis of mononuclear cells. In addition, recent studies also implicated these chemotactic cytokines in the recruitment of neutrophils. The underlying mechanisms remained largely unknown. Using in vivo microscopy on the mouse cremaster muscle, intravascular adherence and subsequent paracellular transmigration of neutrophils elicited by the chemokine (C-C motif) ligand 3 (CCL3, synonym MIP-1α) were significantly diminished in mice with a deficiency of the chemokine (C-C motif) receptor 1 (Ccr1−/−) or 5 (Ccr5−/−). Using cell-transfer techniques, neutrophil responses required leukocyte CCR1 and nonleukocyte CCR5. Furthermore, neutrophil extravasation elicited by CCL3 was almost completely abolished on inhibition of G protein–receptor coupling and PI3Kγ-dependent signaling, while neutrophil recruitment induced by the canonical neutrophil attractants chemokine (C-X-C motif) ligand 1 (CXCL1, synonym KC) or the lipid mediator platetelet-activating factor (PAF) was only partially reduced. Moreover, Ab blockade of β2 integrins, of α4 integrins, or of their putative counter receptors ICAM-1 and VCAM-1 significantly attenuated CCL3-, CXCL1-, or PAF-elicited intravascular adherence and paracellular transmigration of neutrophils. These data indicate that the C-C motif chemokine CCL3 and canonical neutrophil attractants exhibit both common and distinct mechanisms for the regulation of intravascular adherence and transmigration of neutrophils.
Mll partial tandem duplication and Flt3 internal tandem duplication in a double knock-in mouse recapitulates features of counterpart human acute myeloid leukemias
Authors: Zorko Nicholas A. , Bernot Kelsie M. , Whitman Susan P. , Siebenaler Ronald F. , Ahmed Elshafa H. , Marcucci Gabriele G. , Yanes Daniel A. , McConnell Kathleen K. , Mao Charlene , Kalu Chidimma , Zhang Xiaoli , Jarjoura David , Dorrance Adrienne M. , Heerema Nyla A. , Lee Benjamin H. , Huang Gang , Marcucci Guido , Caligiuri Michael A.
Published: June 2012

The MLL-partial tandem duplication (PTD) associates with high-risk cytogenetically normal acute myeloid leukemia (AML). Concurrent presence of FLT3-internal tandem duplication (ITD) is observed in 25% of patients with MLL-PTD AML. However, mice expressing either Mll-PTD or Flt3-ITD do not develop AML, suggesting that 2 mutations are necessary for the AML phenotype. Thus, we generated a mouse expressing both Mll-PTD and Flt3-ITD. MllPTD/WT:Flt3ITD/WT mice developed acute leukemia with 100% penetrance, at a median of 49 weeks. As in human MLL-PTD and/or the FLT3-ITD AML, mouse blasts exhibited normal cytogenetics, decreased Mll-WT-to-Mll-PTD ratio, loss of the Flt3-WT allele, and increased total Flt3. Highlighting the adverse impact of FLT3-ITD dosage on patient survival, mice with homozygous Flt3-ITD alleles, MllPTD/WT:Flt3ITD/ITD, demonstrated a nearly 30-week reduction in latency to overt AML. Here we demonstrate, for the first time, that Mll-PTD contributes to leukemogenesis as a gain-of-function mutation and describe a novel murine model closely recapitulating human AML.
Yeast 5 – an expanded reconstruction of the Saccharomyces cerevisiae metabolic network
Authors: Heavner Benjamin D , Smallbone Kieran , Barker Brandon , Mendes Pedro , Walker Larry P
Published: June 2012

Background

Efforts to improve the computational reconstruction of the Saccharomyces cerevisiae biochemical reaction network and to refine the stoichiometrically constrained metabolic models that can be derived from such a reconstruction have continued since the first stoichiometrically constrained yeast genome scale metabolic model was published in 2003. Continuing this ongoing process, we have constructed an update to the Yeast Consensus Reconstruction, Yeast 5. The Yeast Consensus Reconstruction is a product of efforts to forge a community-based reconstruction emphasizing standards compliance and biochemical accuracy via evidence-based selection of reactions. It draws upon models published by a variety of independent research groups as well as information obtained from biochemical databases and primary literature.

Results

Yeast 5 refines the biochemical reactions included in the reconstruction, particularly reactions involved in sphingolipid metabolism; updates gene-reaction annotations; and emphasizes the distinction between reconstruction and stoichiometrically constrained model. Although it was not a primary goal, this update also improves the accuracy of model prediction of viability and auxotrophy phenotypes and increases the number of epistatic interactions. This update maintains an emphasis on standards compliance, unambiguous metabolite naming, and computer-readable annotations available through a structured document format. Additionally, we have developed MATLAB scripts to evaluate the model’s predictive accuracy and to demonstrate basic model applications such as simulating aerobic and anaerobic growth. These scripts, which provide an independent tool for evaluating the performance of various stoichiometrically constrained yeast metabolic models using flux balance analysis, are included as Additional files 1, 2 and 3.

Conclusions

Yeast 5 expands and refines the computational reconstruction of yeast metabolism and improves the predictive accuracy of a stoichiometrically constrained yeast metabolic model. It differs from previous reconstructions and models by emphasizing the distinction between the yeast metabolic reconstruction and the stoichiometrically constrained model, and makes both available as Additional file 4 and Additional file 5 and at http://yeast.sf.net/ as separate systems biology markup language (SBML) files. Through this separation, we intend to make the modeling process more accessible, explicit, transparent, and reproducible.
Giant cell tumor of the distal ulna: a case report
Authors: Vanni Daniele , Pantalone Andrea , Andreoli Elda , Caldora Patrizio , Salini Vincenzo
Published: June 2012

Introduction

Several cases of long bone giant cell tumor have been reported in the literature. We report the case of a patient with a giant cell tumor in the distal ulna. This is very unusual, with a reported incidence of 0.45 to 6%.

Case presentation

A 17-year-old Colombian man presented with a painful swelling of the left wrist. After performing an instrumental examination, a diagnosis of distal ulna giant cell tumor was made. The tumor was treated with an intralesional curettage, phenol application and bone grafting.

Conclusions

This tumor may have a good prognosis if it is diagnosed early and radically treated. It is important to be aware of atypical cancer localizations in order to perform a proper diagnosis.
Upregulation of tumor necrosis factor receptor-associated factor 6 correlated with synovitis severity in rheumatoid arthritis
Authors: Zhu Lang-Jing , Dai Lie , Zheng Dong-Hui , Mo Ying-Qian , Ou-Yang Xia , Wei Xiu-Ning , Shen Jun , Zhang Bai-Yu
Published: June 2012

Introduction

Rheumatoid arthritis (RA) is a chronic inflammatory disease leading to joint destruction and disability. Focal bone erosion is due to excess bone resorption of osteoclasts. Tumor necrosis factor receptor-associated factor 6 (TRAF6) is one of the critical mediators both in inflammatory signal pathway and differentiation and resorption activity of osteoclasts. Here we aimed to investigate TRAF6 expression in RA synovium and its correlation with histological synovitis severity and radiological joint destruction in RA.

Methods

Synovitis score was determined in needle biopsied synovium from 44 patients with active RA. Synovium from nine patients with osteoarthritis (OA) and seven with orthopedic arthropathies (Orth.A) were enrolled as "less inflamed" disease controls. Serial sections were stained immunohistochemically for TRAF6 as well as CD68 (macrophage), CD3 (T cell), CD20 (B cell), CD38 (plasmocyte), CD79a (B lineage cells from pre-B cell to plasmocyte stage), and CD34 (endothelial cell). Double immunofluorescence staining of TRAF6 and CD68 were tested. Densities of positive staining cells were determined and correlated with histological disease activity (synovitis score) and radiographic joint destruction (Sharp score).

Results

TRAF6 expression was found in the intimal and subintimal area of RA synovium, with intense staining found in the endochylema and nucleus of intimal synoviocytes and subintimal inflammatory cells. Double immunofluorescence staining showed TRAF6 was expressed in most of the intimal cells and obviously expressed in CD68+ cells and some other CD68- cells in subintimal area. Synovial TRAF6 was significantly over-expressed in the RA group compared with the OA and Orth.A group (2.53 ± 0.94 vs. 0.72 ± 0.44 and 0.71 ± 0.49, P < 0.0001). Synovial TRAF6 expression in RA correlated significantly with synovitis score (r = 0.412, P = 0.006), as well as the inflammatory cell infiltration (r = 0.367, P = 0.014). Significant correlation was detected between synovial TRAF6 expression and intimal CD68+ cells, as well as the cell density of subintimal CD68+ cells, CD3+ cells, CD20+ cells, CD38+ cells, and CD79a+ cells (all P < 0.05).

Conclusions

Elevated synovial TRAF6 expression correlated with synovitis severity and CD68+ cell density in RA. It is, therefore, hypothesized that synovial TRAF6 is involved in the pathogenesis of synovial inflammation and osteoclast differentiation in RA.
The Role of Bile After Roux-en-Y Gastric Bypass in Promoting Weight Loss and Improving Glycaemic Control
Authors: Pournaras Dimitri J. , Glicksman Clare , Vincent Royce P. , Kuganolipava Shophia , Alaghband-Zadeh Jamie , Mahon David , Bekker Jan H.R. , Ghatei Mohammad A. , Bloom Stephen R. , Walters Julian R.F. , Welbourn Richard , le Roux Carel W.
Published: June 2012

Gastric bypass leads to the remission of type 2 diabetes independently of weight loss. Our hypothesis is that changes in bile flow due to the altered anatomy may partly explain the metabolic outcomes of the operation. We prospectively studied 12 patients undergoing gastric bypass and six patients undergoing gastric banding over a 6-wk period. Plasma fibroblast growth factor (FGF)19, stimulated by bile acid absorption in the terminal ileum, and plasma bile acids were measured. In canine and rodent models, we investigated changes in the gut hormone response after altered bile flow. FGF19 and total plasma bile acids levels increased after gastric bypass compared with no change after gastric banding. In the canine model, both food and bile, on their own, stimulated satiety gut hormone responses. However, when combined, the response was doubled. In rats, drainage of endogenous bile into the terminal ileum was associated with an enhanced satiety gut hormone response, reduced food intake, and lower body weight. In conclusion, after gastric bypass, bile flow is altered, leading to increased plasma bile acids, FGF19, incretin. and satiety gut hormone concentrations. Elucidating the mechanism of action of gastric bypass surgery may lead to novel treatments for type 2 diabetes.
Up-Regulating Relaxin Expression by G-Quadruplex Interactive Ligand to Achieve Antifibrotic Action
Authors: Gu Hui-Ping , Lin Sen , Xu Ming , Yu Hai-Yi , Du Xiao-Jun , Zhang You-Yi , Yuan Gu , Gao Wei
Published: June 2012

Myocardial fibrosis is a key pathological change in a variety of heart diseases contributing to the development of heart failure, arrhythmias, and sudden death. Recent studies have shown that relaxin prevents and reverses cardiac fibrosis. Endogenous expression of relaxin was elevated in the setting of heart disease; the extent of such up-regulation, however, is insufficient to exert compensatory actions, and the mechanism regulating relaxin expression is poorly defined. In the rat relaxin-1 (RLN1, Chr1) gene promoter region we found presence of repeated guanine (G)-rich sequences, which allowed formation and stabilization of G-quadruplexes with the addition of a G-quadruplex interactive ligand berberine. The G-rich sequences and the G-quadruplexes were localized adjacent to the binding motif of signal transducer and activator of transcription (STAT)3, which negatively regulates relaxin expression. Thus, we hypothesized that the formation and stabilization of G-quadruplexes by berberine could influence relaxin expression. We found that berberine-induced formation of G-quadruplexes did increase relaxin gene expression measured at mRNA and protein levels. Formation of G-quadruplexes significantly reduced STAT3 binding to the promoter of relaxin gene. This was associated with consequent increase in the binding of RNA polymerase II and STAT5a to relaxin gene promoter. In cardiac fibroblasts and rats treated with angiotensin II, berberine was found to suppress fibroblast activation, collagen synthesis, and extent of cardiac fibrosis through up-regulating relaxin. The antifibrotic action of berberine in vitro and in vivo was similar to that by exogenous relaxin. Our findings document a novel therapeutic strategy for fibrosis through up-regulating expression of endogenous relaxin.
Orexin A Suppresses Gonadotropin-Releasing Hormone (GnRH) Neuron Activity in the Mouse
Authors: Gaskins Garrett T. , Moenter Suzanne M.
Published: June 2012

GnRH neurons are critical for the central regulation of fertility, integrating steroidal, metabolic and other cues. GnRH neurons appear to lack receptors for many of these cues, suggesting involvement of afferent systems to convey information. Orexin A (orexin) is of interest in this regard as a neuromodulator that up-regulates metabolic activity, increases wakefulness, and affects GnRH/LH release. We examined the electrophysiological response of GnRH neurons to orexin application and how this response changes with estradiol and time of day in a defined animal model. Mice were either ovariectomized (OVX) or OVX and implanted with estradiol capsules (OVX+E). GnRH neurons from OVX+E mice exhibit low firing rates in the morning, due to estradiol-negative feedback, and high firing rates in the evening, due to positive feedback. Orexin inhibited activity of GnRH neurons from OVX mice independent of time of day. In GnRH neurons from OVX+E mice, orexin was inhibitory during the evening, suggesting orexin inhibition is not altered by estradiol. No effect of orexin was observed in OVX+E morning recordings, due to low basal GnRH activity. Inhibitory effects of orexin were mediated by the type 1 orexin receptor, but antagonism of this receptor did not increase GnRH neuron activity during estradiol-negative feedback. Spike pattern analysis revealed orexin increases interevent interval by reducing the number of single spikes and bursts. Orexin reduced spikes/burst and burst duration but did not affect intraburst interval. This suggests orexin may reduce overall firing rate by suppressing spike initiation and burst maintenance in GnRH neurons.
Regulated temporal-spatial astrocyte precursor cell proliferation involves BRAF signalling in mammalian spinal cord
Authors: Tien An-Chi , Tsai Hui-Hsin , Molofsky Anna V. , McMahon Martin , Foo Lynette C. , Kaul Aparna , Dougherty Joseph D. , Heintz Nathaniel , Gutmann David H. , Barres Ben A. , Rowitch David H.
Published: June 2012

Expansion of astrocyte populations in the central nervous system is characteristic of evolutionarily more complex organisms. However, regulation of mammalian astrocyte precursor proliferation during development remains poorly understood. Here, we used Aldh1L1-GFP to identify two morphologically distinct types of proliferative astrocyte precursors: radial glia (RG) in the ventricular zone and a second cell type we call an ‘intermediate astrocyte precursor’ (IAP) located in the mantle region of the spinal cord. Astrogenic RG and IAP cells proliferated in a progressive ventral-to-dorsal fashion in a tight window from embryonic day 13.5 until postnatal day 3, which correlated precisely with the pattern of active ERK signalling. Conditional loss of BRAF function using BLBP-cre resulted in a 20% decrease in astrocyte production, whereas expression of activated BRAFV600E resulted in astrocyte hyperproliferation. Interestingly, BRAFV600E mitogenic effects in astrocytes were restricted, in part, by the function of p16INK4A-p19ARF, which limited the temporal epoch for proliferation. Together, these findings suggest that astrocyte precursor proliferation involves distinct RG and IAP cells; is subjected to temporal and spatial control; and depends in part on BRAF signalling at early stages of mammalian spinal cord development.
Wunen, a Drosophila lipid phosphate phosphatase, is required for septate junction-mediated barrier function
Authors: Ile Kristina E. , Tripathy Ratna , Goldfinger Valentina , Renault Andrew D.
Published: June 2012

Lipid phosphate phosphatases (LPPs) are integral membrane enzymes that regulate the levels of bioactive lipids such as sphingosine 1-phosphate and lysophosphatidic acid. The Drosophila LPPs Wunen (Wun) and Wunen-2 (Wun2) have a well-established role in regulating the survival and migration of germ cells. We now show that wun has an essential tissue-autonomous role in development of the trachea: the catalytic activity of Wun is required to maintain septate junction (SJ) paracellular barrier function, loss of which causes failure to accumulate crucial luminal components, suggesting a role for phospholipids in SJ function. We find that the integrity of the blood-brain barrier is also lost in wun mutants, indicating that loss of SJ function is not restricted to the tracheal system. Furthermore, by comparing the rescue ability of different LPP homologs we show that wun function in the trachea is distinct from its role in germ cell migration.
DEVELOPMENT-RELATED PcG TARGET IN THE APEX 4 controls leaf margin architecture in Arabidopsis thaliana
Authors: Engelhorn Julia , Reimer Julia J. , Leuz Iris , Göbel Ulrike , Huettel Bruno , Farrona Sara , Turck Franziska
Published: June 2012

In a reverse genetics screen based on a group of genes enriched for development-related Polycomb group targets in the apex (DPAs), we isolated DPA4 as a novel regulator of leaf margin shape. T-DNA insertion lines in the DPA4 locus display enhanced leaf margin serrations and enlarged petals, whereas overexpression of DPA4 results in smooth margins. DPA4 encodes a putative RAV (Related to ABI3/VP1) transcriptional repressor and is expressed in the lateral organ boundary region and in the sinus of leaf serrations. DPA4 expression domains overlap with those of the known leaf shape regulator CUP-SHAPED COTYLEDON 2 (CUC2) and we provide evidence that DPA4 negatively regulates CUC2 expression independently of MIR164A, an established regulator of CUC2. Taken together, the data suggest DPA4 as a newly identified player in the signalling network that controls leaf serrations in Arabidopsis thaliana.
Evolutionarily conserved requirement of Cdx for post-occipital tissue emergence
Authors: van Rooijen Carina , Simmini Salvatore , Bialecka Monika , Neijts Roel , van de Ven Cesca , Beck Felix , Deschamps Jacqueline
Published: June 2012

Mouse Cdx genes are involved in axial patterning and partial Cdx mutants exhibit posterior embryonic defects. We found that mouse embryos in which all three Cdx genes are inactivated fail to generate any axial tissue beyond the cephalic and occipital primordia. Anterior axial tissues are laid down and well patterned in Cdx null embryos, and a 3′ Hox gene is initially transcribed and expressed in the hindbrain normally. Axial elongation stops abruptly at the post-occipital level in the absence of Cdx, as the posterior growth zone loses its progenitor activity. Exogenous Fgf8 rescues the posterior truncation of Cdx mutants, and the spectrum of defects of Cdx null embryos matches that resulting from loss of posterior Fgfr1 signaling. Our data argue for a main function of Cdx in enforcing trunk emergence beyond the Cdx-independent cephalo-occipital region, and for a downstream role of Fgfr1 signaling in this function. Cdx requirement for the post-head section of the axis is ancestral as it takes place in arthropods as well.
Determination of Sulfamethoxydiazine in Pig Feed Based on Transmittance near Infrared Spectra
Authors: Fu Qingbo , He Xinping , Suo Hui , Wang Jinming , Zhao Chun
Published: June 2012

A rapid method for the determination of sulfamethoxydiazine in pig feed was developed using transmittance near infrared spectroscopy in combination with partial least squares calibration. Sulfamethoxydiazine in pig feed was extracted with acetonitrile then the transmittance spectra were recorded directly on the extract. Various spectral pre-treatment methods, including derivative, orthogonal signal correction, multiplicative scatter correction and standard normal variate were compared. The forward interval partial least squares strategy was used to select the variables. Results showed that the suitable wavenumber ranges were 7289–6823 cm−1 combined with 5407–4940 cm−1 and the second derivative was the best pre-treatment method. The multivariable detection limit (MDL) and multivariable quantification limit (MQL) were analysed and utilised as indicators to select the proper calibration sample numbers and the concentration ranges. In accordance with these criteria, 24 samples were appropriate for the wide range of 16–560 mg kg−1 and the narrower calibration range of 16–152 mg kg−1 provided lower MDL and MQL:8.7 mg kg−1 and 28.8 mg kg−1 with α = 0.05, respectively. The 16–152 mg kg−1 model was tested by determining three different batches of commercial pig feed and relative residuals lower than 7% were obtained. It was found that the concentration range was a critical aspect and a narrow range with low levels was recommended for the determination of analyte at low level and the transmittance near infrared approach developed was fast and reliable, allowing a strict control of the sulfamethoxydiazine in pig feed.
Prediction Error Improvements Using Variable Selection on Small Calibration Sets—A Comparison of Some Recent Methods
Authors: Øvergaard Stein Ivar , Pierna Juan Antonio Fernández , Baeten Vincent , Dardenne Pierre , Isaksson Tomas
Published: June 2012

Variable selection provides useful information about the most important predictors in the dataset, information which is not always available at the beginning of an analysis. Two recent variable selection methods, backward variable selection for partial least squares (BVSPLS) and powered partial least squares (PPLS), were compared against each other and against forward stepwise selection (FSS) and full spectrum partial least squares (PLS) in terms of their ability to produce accurate prediction models in NIR spectroscopy data. All four regression methods were studied using three different NIR datasets. PPLS and BVSPLS gave good prediction results in all three datasets, even with a very limited number of calibration samples available (<40). All methods gave similar prediction results when the number of calibration samples was higher (>150). PPLS gave the best predictive performance of all methods and also gave the selections of variables that were most easily assigned to specific chemical bonds. Hence, the PPLS models were more easily interpretable than the other models. This study quantifies differences between the two recent variable selection methods as well as the differences between recent methods and more established methods. Moreover, if the number of calibration samples can be reduced through variable selection, the labour and cost associated with wet chemistry reference methods can be reduced accordingly.
Visible-Near Infrared Spectral Sensing Coupled with Chemometric Analysis as a Method for on-line Prediction of Milled Biomass Composition Pre-Pelletising
Authors: Everard Colm D. , Fagan Colette C. , McDonnell Kevin P.
Published: June 2012

Chemical composition of biomass is critical to conversion efficiency during pelletisation. Visible-near infrared (vis–NIR) spectral sensing is a rapid and non-destructive sensing technology. The potential of on-line vis–NIR spectral sensing, in conjunction with chemometrics, to predict moisture, carbon and ash contents of milled Miscanthus and two short rotation coppice willow varieties was assessed. Spectroscopic information within the vis–NIR waveband of 400–1000 nm was analysed. Principal component analysis was successfully used to distinguish between the three varieties of biomass. Partial least squares regression validation models for moisture prediction over a range of 1.9–37.0% gave a coefficient of determination ( r2) of 0.95 with a root mean square error of prediction of 2.5%. Carbon and ash cross-validation models achieved r2 = 0.85 and 0.50, respectively. These results were for a multiple biomass variety sample set. Results demonstrate on-line vis–NIR spectral sensing combined with chemometrics has the potential to be employed in an integrated pelletising management system.
Preliminary proteomic-based identification of a novel protein for Down's syndrome in maternal serum
Authors: Yu Bin , Zhang Bin , Wang Jing , Wang Qiu-wei , Huang Rui-ping , Yang Yu-qi , Shao Shi-he
Published: June 2012

Prenatal screening for Down's syndrome (DS) is in need of improvement. As a powerful platform, proteomics techniques could also be used for identification of new biomarkers for DS screening. In this case-control proteome study, pregnant women were diagnosed prenatally by karyotype analysis from amniotic fluid (AF). Maternal serum samples were collected from six pregnancies with fetuses affected by DS and six pregnancies with normal fetuses. First, we used two-dimensional electrophoresis and mass spectrometry to identify the different levels of expression of proteins in maternal serum between the DS and control groups in the second trimester. Second, we used bioinformatics to analyze the proteins by DAVID. Then, the interesting candidates were further tested by enzyme-linked immunosorbent assay (ELISA). Twenty-nine proteins were successfully identified in maternal serum obtained from pregnancies with fetuses affected by DS. The top five proteins up-regulated were serotransferrin (TF), alpha-1b-glycoprotein (A1BG), desmin (DES), alpha-1-antitrypsin (SERPINA1) and ceruloplasmin (CP), while serum amyloid P-component (APCS) was the most down-regulated protein. These 29 proteins were categorized based on binding, catalytic activity and enzyme regulator activity. The biological roles were involved in biological regulation, metabolic processes, cellular processes and response to a stimulus. Based on ELISA, the median concentrations of CP and complement factor B (CFB) were 332.3 and 412.3 ng/mL, respectively. The concentrations of CP and CFB were significantly higher in the DS group than in the control group ( P < 0.05). In conclusion, proteomic approaches offer the possibility of further improving the performance of DS screening and our identification of up- and down-regulated proteins may lead to new candidates for DS screening.
Mesenchymal stem cells relieve fibrosis of Schistosoma japonicum-induced mouse liver injury
Authors: Xu Huijuan , Qian Hui , Zhu Wei , Zhang Xu , Yan Yongmin , Mao Fei , Wang Mei , Xu Huitao , Xu Wenrong
Published: June 2012

Mesenchymal stem cells (MSCs) have gained popularity for their potential as seed cells to treat various human diseases, including pathogenic infections. Schistosoma japonicum ( S. japonicum) infection is characterized by formation of parasite egg granulomas and host liver fibrosis. MSCs have been proposed as useful treatments of S. japonicum infection, but the efficacy and underlying mechanisms remain unknown. Herein, we report that MSCs were able to ameliorate S. japonicum-induced liver injury in vivo and this effect was enhanced by combining MSCs with conventional drug praziquantel (PZQ). Kunming strains of mice were infected with S. japonicum and treated with vehicle, MSCs, PZQ or PZQ + MSCs. MSC treatment not only prolonged the survival time of infected mice but reduced egg granuloma diameter and decreased the concentrations of serum transforming growth factor- β1 and hyaluronic acid. MSC treatment also inhibited collagen deposition and reduced the expression of collagen type 3, α-smooth muscle actin and vimentin in infected mouse liver tissues. Collectively, our findings suggest that MSC treatment represents a novel therapeutic approach for S. japonicum-induced liver injury and fibrosis.
Ex vivo imaging of mouse brain using micro-CT with non-ionic iodinated contrast agent: a comparison with myelin staining
Authors: Saito S , Murase K
Published: June 2012

Objective

We investigated the use of micro-CT with contrast agent for the non-invasive characterisation of fixed mouse brain tissue specimens as a means to differentiate between grey and white matter.

Methods

Nine mice were divided into two groups for micro-CT (n=6) and myelin staining (n=3) experiments. Six mice underwent in vivo micro-CT and were then prepared for brain specimens by transcardiac perfusion with paraformaldehyde. The six mouse brains were soaked in two different concentrations of non-ionic iodinated contrast agents (60 and 150 mg ml−1). Immersion times used for each concentration of iodine were for 3, 7 and 14 days. Three-dimensional ex vivo micro-CT images were acquired with a resolution of 39 μm3 to create isotropic images. The other three mice were stained for evaluation of the myelin structure.

Results

Soaking the brains in non-ionic iodinated contrast agent resulted in clear differences in signal between the grey matter, the white matter and the ventricular spaces. The 150 mg ml−1 contrast agent solution yielded images with better contrast-to-noise ratio (CNR) than 60 mg ml−1 iodine contrast agent solution. 14 days of soaking yielded images with better CNR than 3 and 7 days. The CT contrast of grey and white matter derived from the iodine-soaked fixed brains was strongly related to tissue myelin.

Conclusion

The present study demonstrated that micro-CT can be used to detect the mouse brain myelin structure at 3, 7 and 14 days after fixation using a CT contrast agent.
Focal testicular lesions: colour Doppler ultrasound, contrast-enhanced ultrasound and tissue elastography as adjuvants to the diagnosis
Authors: Huang D Y , Sidhu P S
Published: June 2012

The aim of this review is to illustrate the potential of different and newer ultrasound techniques beyond conventional B-mode imaging, including colour Doppler ultrasound, contrast-enhanced ultrasound (CEUS) and tissue elastography, in the characterisation of both benign and malignant intratesticular lesions. Normally, testicular malignancies, either primary or secondary, demonstrate an increase in colour Doppler signal. However, there is a diversity of benign testicular lesions that may mimic testicular malignancies. The use of CEUS improves characterisation of testicular lesions, and confirms lack of vascularity in benign abnormalities such as epidermoid cysts, infarctions, abscesses and changes following trauma. Tissue elastography allows further evaluation of the cellular consistency of the abnormality. Familiarity with the appearances seen with these ultrasound techniques in both benign and malignant abnormalities should aid in improving confidence in arriving at the correct diagnosis.
Percutaneous testicular biopsy for indeterminate testicular lesions
Authors: Shaida N , Berman L H
Published: June 2012

Ultrasound forms an important part of the assessment of the testicle. Nevertheless, there are a number of situations in which clinical and radiological assessment is unable to provide a definitive diagnosis of a testicular lump. In these situations, historically, either open biopsy or orchidectomy has been performed. Ultrasound-guided percutaneous testicular biopsy is an alternative, less invasive method of obtaining histological diagnosis. Here we describe the rationale, technique and potential uses of the technique.
Totally implantable venous power ports of the forearm and the chest: initial clinical experience with port devices approved for high-pressure injections
Authors: Goltz J P , Noack C , Petritsch B , Kirchner J , Hahn D , Kickuth R
Published: June 2012

Objectives

To evaluate the technical success, clinical outcome and safety of percutaneously placed totally implantable venous power ports (TIVPPs) approved for high-pressure injections, and to analyse their value for arterial phase CT scans.

Methods

Retrospectively, we identified 204 patients who underwent TIVPP implantation in the forearm (n=152) or chest (n=52) between November 2009 and May 2011. Implantation via an upper arm (forearm port, FP) or subclavian vein (chest port, CP) was performed under sonographic and fluoroscopic guidance. Complications were evaluated following the standards of the Society of Interventional Radiology. Power injections via TIVPPs were analysed, focusing on adequate functioning and catheter's tip location after injection. Feasibility of automatic bolus triggering, peak injection pressure and arterial phase aortic enhancement were evaluated and compared with 50 patients who had had power injections via classic peripheral cannulas.

Results

Technical success was 100%. Procedure-related complications were not observed. Catheter-related thrombosis was diagnosed in 15 of 152 FPs (9.9%, 0.02/100 catheter days) and in 1 of 52 CPs (1.9%, 0.002/100 catheter days) (p<0.05). Infectious complications were diagnosed in 9 of 152 FPs (5.9%, 0.014/100 catheter days) and in 2 of 52 CPs (3.8%, 0.003/100 catheter days) (p>0.05). Arterial bolus triggering succeeded in all attempts; the mean injection pressure was 213.8 psi. Aortic enhancement did not significantly differ between injections via cannulas and TIVPPs (p>0.05).

Conclusions

TIVPPs can be implanted with high technical success rates, and are associated with low rates of complications if implanted with sonographic and fluoroscopic guidance. Power injections via TIVPPs are safe and result in satisfying arterial contrast. Conventional ports should be replaced by TIVPPs.
A Binary Search Heuristic Algorithm Based on Randomized Local Search for the Rectangular Strip-Packing Problem
Authors: Zhang Defu , Wei Lijun , Leung Stephen C. H. , Chen Qingshan
Published: June 2012

This paper presents a binary search heuristic algorithm for the rectangular strip-packing problem. The problem is to pack a number of rectangles into a sheet of given width and infinite height so as to minimize the required height. We first transform this optimization problem into a decision problem. A least-waste-first strategy and a minimal-inflexion-first strategy are proposed to solve the related decision problem. Lastly, we develop a binary search heuristic algorithm based on randomized local search to solve the original optimization problem. The computational results on six classes of benchmark problems have shown that the presented algorithm can find better solutions within a reasonable time than the published best heuristic algorithms for most zero-waste instances. In particular, the presented algorithm is proved to be the dominant algorithm for large zero-waste instances.
Interpreting the Contaminated Land Regime: Should the ‘Polluter’ Pay?
Authors: Lees Emma
Published: June 2012

The contaminated land regime is not as effective as it could be. It is suggested that part of the reason for this is that enforcing authorities cannot afford to clean up land at a faster rate. Yet they are reluctant to recover their costs from Class B persons. There is evidence that local authorities believe that ‘innocent’ homeowners ought not to face the cost of remediation. This is, at least in part, because of a focus on the ‘polluter pays' principle. There seems to be a belief that, as they are not polluters, homeowners should not have to pay. Unfortunately this conclusion does not follow, leading to a misinterpretation of the ‘hardship test’ in section 78P of the Environmental Protection Act 1990. Instead, there should be a more explicit recognition that there are other principles in the background framework to the regime. In particular, the principle of stewardship provides a justification for homeowners to pay to remediate their land. If this is recognised, it is hoped that both local authorities and the Environment Agency will be encouraged to recover at least some of their costs from Class B persons which should free up funds to survey more land to determine levels of contamination, and to allow a clean-up of truly orphan sites.
Interface engineering: Boosting the energy conversion efficiencies for nanostructured solar cells
Authors: Liu Guodong , Ji Shulin , Xu Guoping , Ye Changhui
Published: June 2012

Nanostructured solar cells have attracted increasing attention in recent years because their low cost and ease of preparation offer unique advantages and opportunities unavailable with conventional single-crystalline solar cells. The efficiencies of this kind of solar cell largely depend on the interfacial structure owing to the large specific interface areas and the inherent high density of interface states. In this review article, strategies of interface engineering will be introduced in detail. The up-to-date progress and understanding of interface engineering and its role in influencing the efficiency of nanostructured solar cells will be discussed. Some of the representative examples of the interface engineering method will be presented wherever necessary. Continued boosting of the energy conversion efficiency for nanostructured solar cells is anticipated in the coming years and will bring this kind of solar cell to the status of commercialization.