bluuebunny/crossref_metadata_2025 huggingface dataset:
Whole Genome Profiling provides a robust framework for physical mapping and sequencing in the highly complex and repetitive wheat genome
Authors: Philippe Romain , Choulet Frédéric , Paux Etienne , van Oeveren Jan , Tang Jifeng , Wittenberg Alexander HJ , Janssen Antoine , van Eijk Michiel JT , Stormo Keith , Alberti Adriana , Wincker Patrick , Akhunov Eduard , van der Vossen Edwin , Feuillet Catherine
Published: January 2012

Background

Sequencing projects using a clone-by-clone approach require the availability of a robust physical map. The SNaPshot technology, based on pair-wise comparisons of restriction fragments sizes, has been used recently to build the first physical map of a wheat chromosome and to complete the maize physical map. However, restriction fragments sizes shared randomly between two non-overlapping BACs often lead to chimerical contigs and mis-assembled BACs in such large and repetitive genomes. Whole Genome Profiling (WGP™) was developed recently as a new sequence-based physical mapping technology and has the potential to limit this problem.

Results

A subset of the wheat 3B chromosome BAC library covering 230 Mb was used to establish a WGP physical map and to compare it to a map obtained with the SNaPshot technology. We first adapted the WGP-based assembly methodology to cope with the complexity of the wheat genome. Then, the results showed that the WGP map covers the same length than the SNaPshot map but with 30% less contigs and, more importantly with 3.5 times less mis-assembled BACs. Finally, we evaluated the benefit of integrating WGP tags in different sequence assemblies obtained after Roche/454 sequencing of BAC pools. We showed that while WGP tag integration improves assemblies performed with unpaired reads and with paired-end reads at low coverage, it does not significantly improve sequence assemblies performed at high coverage (25x) with paired-end reads.

Conclusions

Our results demonstrate that, with a suitable assembly methodology, WGP builds more robust physical maps than the SNaPshot technology in wheat and that WGP can be adapted to any genome. Moreover, WGP tag integration in sequence assemblies improves low quality assembly. However, to achieve a high quality draft sequence assembly, a sequencing depth of 25x paired-end reads is required, at which point WGP tag integration does not provide additional scaffolding value. Finally, we suggest that WGP tags can support the efficient sequencing of BAC pools by enabling reliable assignment of sequence scaffolds to their BAC of origin, a feature that is of great interest when using BAC pooling strategies to reduce the cost of sequencing large genomes.
Ezetimibe/simvastatin 10/40 mg versus atorvastatin 40 mg in high cardiovascular risk patients with primary hypercholesterolemia: a randomized, double-blind, active-controlled, multicenter study
Authors: Hing Ling Paul Kah , Civeira Fernando , Dan Andrei Gheorghe , Hanson Mary E , Massaad Rachid , De Tilleghem Celine Le Bailly , Milardo Christopher , Triscari Joseph
Published: January 2012

Background

A considerable number of patients with severely elevated LDL-C do not achieve recommended treatment targets, despite treatment with statins. Adults at high cardiovascular risk with hypercholesterolemia and LDL-C ≥ 2.59 and ≤ 4.14 mmol/L (N = 250), pretreated with atorvastatin 20 mg were randomized to ezetimibe/simvastatin 10/40 mg or atorvastatin 40 mg for 6 weeks. The percent change in LDL-C and other lipids was assessed using a constrained longitudinal data analysis method with terms for treatment, time, time-by-treatment interaction, stratum, and time-by-stratum interaction. Percentage of subjects achieving LDL-C < 1.81 mmol/L, < 2.00 mmol/L, or < 2.59 mmol/L was assessed using a logistic regression model with terms for treatment and stratum. Tolerability was assessed.

Results

Switching to ezetimibe/simvastatin resulted in significantly greater changes in LDL-C (-26.81% vs.-11.81%), total cholesterol (-15.97% vs.-7.73%), non-HDL-C (-22.50% vs.-10.88%), Apo B (-17.23% vs.-9.53%), and Apo A-I (2.56% vs.-2.69%) vs. doubling the atorvastatin dose (all p ≤ 0.002), but not HDL-C, triglycerides, or hs-CRP. Significantly more subjects achieved LDL-C < 1.81 mmol/L (29% vs. 5%), < 2.00 mmol/L (38% vs. 9%) or < 2.59 mmol/L (69% vs. 41%) after switching to ezetimibe/simvastatin vs. doubling the atorvastatin dose (all p < 0.001). The overall safety profile appeared generally comparable between treatment groups.

Conclusions

In high cardiovascular risk subjects with hypercholesterolemia already treated with atorvastatin 20 mg but not at LDL-C < 2.59 mmol/L, switching to combination ezetimibe/simvastatin 10/40 mg provided significantly greater LDL-C lowering and greater achievement of LDL-C targets compared with doubling the atorvastatin dose to 40 mg. Both treatments were generally well-tolerated.

Trial registration

Registered at clinicaltrials.gov: NCT00782184
Adaptive access and rate control of CSMA for energy, rate, and delay optimization
Authors: Khodaian Mahdi , Pérez Jesús , Khalaj Babak H , Crespo Pedro M
Published: January 2012

In this article, we present a cross-layer adaptive algorithm that dynamically maximizes the average utility function. A per stage utility function is defined for each link of a carrier sense multiple access-based wireless network as a weighted concave function of energy consumption, smoothed rate, and smoothed queue size. Hence, by selecting weights we can control the trade-off among them. Using dynamic programming, the utility function is maximized by dynamically adapting channel access, modulation, and coding according to the queue size and quality of the time-varying channel. We show that the optimal transmission policy has a threshold structure versus the channel state where the optimal decision is to transmit when the wireless channel state is better than a threshold. We also provide a queue management scheme where arrival rate is controlled based on the link state. Numerical results show characteristics of the proposed adaptation scheme and highlight the trade-off among energy consumption, smoothed data rate, and link delay.
Single vesicle imaging indicates distinct modes of rapid membrane retrieval during nerve growth
Authors: Hines Jacob H , Henle Steven J , Carlstrom Lucas P , Abu-Rub Mohammad , Henley John R
Published: January 2012

Background

During nerve growth, cytoplasmic vesicles add new membrane preferentially to the growth cone located at the distal tip of extending axons. Growth cone membrane is also retrieved locally, and asymmetric retrieval facilitates membrane remodeling during growth cone repulsion by a chemorepellent gradient. Moreover, growth inhibitory factors can stimulate bulk membrane retrieval and induce growth cone collapse. Despite these functional insights, the processes mediating local membrane remodeling during axon extension remain poorly defined.

Results

To investigate the spatial and temporal dynamics of membrane retrieval in actively extending growth cones, we have used a transient labeling and optical recording method that can resolve single vesicle events. Live-cell confocal imaging revealed rapid membrane retrieval by distinct endocytic modes based on spatial distribution in Xenopus spinal neuron growth cones. These modes include endocytic "hot-spots" triggered at the base of filopodia, at the lateral margins of lamellipodia, and along dorsal ridges of the growth cone. Additionally, waves of endocytosis were induced when individual filopodia detached from the substrate and fused with the growth cone dorsal surface or with other filopodia. Vesicle formation at sites of membrane remodeling by self-contact required F-actin polymerization. Moreover, bulk membrane retrieval by macroendocytosis correlated positively with the substrate-dependent rate of axon extension and required the function of Rho-family GTPases.

Conclusions

This study provides insight into the dynamic membrane remodeling processes essential for nerve growth by identifying several distinct modes of rapid membrane retrieval in the growth cone during axon extension. We found that endocytic membrane retrieval is intensified at specific subdomains and may drive the dynamic membrane ruffling and re-absorption of filopodia and lamellipodia in actively extending growth cones. The findings offer a platform for determining the molecular mechanisms of distinct endocytic processes that may remodel the surface distribution of receptors, ion channels and other membrane-associated proteins locally to drive growth cone extension and chemotactic guidance.
Systemic inhibition of myeloid dendritic cells by circulating HLA class I molecules in HIV-1 infection
Authors: Huang Jinghe , Al-Mozaini Maha , Rogich Jerome , Carrington Mary F , Seiss Katherine , Pereyra Florencia , Lichterfeld Mathias , Yu Xu G
Published: January 2012

Background

HIV-1 infection is associated with profound dysfunction of myeloid dendritic cells, for reasons that remain ill-defined. Soluble HLA class I molecules can have important inhibitory effects on T cells and NK cells, but may also contribute to reduced functional properties of professional antigen-presenting cells. Here, we investigated the expression of soluble HLA class I isoforms during HIV-1 infection and assessed their functional impact on antigen-presenting characteristics of dendritic cells.

Results

Soluble HLA class I molecules were highly upregulated in progressive HIV-1 infection as determined by quantitative Western blots. This was associated with strong increases of intracellular expression of HLA class I isoforms in dendritic cells and monocytes. Using mixed lymphocyte reactions, we found that soluble HLA class I molecules effectively inhibited the antigen-presenting properties of dendritic cells, however, there was no significant influence of HLA class I molecules on the cytokine-secretion properties of these cells. The immunomodulatory effects of soluble HLA class I molecules were mediated by interactions with inhibitory myelomonocytic MHC class I receptors from the Leukocyte Immunoglobulin Like Receptor (LILR) family.

Conclusions

During progressive HIV-1 infection, soluble HLA class I molecules can contribute to systemic immune dysfunction by inhibiting the antigen-presenting properties of myeloid dendritic cells through interactions with inhibitory myelomonocytic HLA class I receptors.
FAME, the Flux Analysis and Modeling Environment
Authors: Boele Joost , Olivier Brett G , Teusink Bas
Published: January 2012

Background

The creation and modification of genome-scale metabolic models is a task that requires specialized software tools. While these are available, subsequently running or visualizing a model often relies on disjoint code, which adds additional actions to the analysis routine and, in our experience, renders these applications suboptimal for routine use by (systems) biologists.

Results

The Flux Analysis and Modeling Environment (FAME) is the first web-based modeling tool that combines the tasks of creating, editing, running, and analyzing/visualizing stoichiometric models into a single program. Analysis results can be automatically superimposed on familiar KEGG-like maps. FAME is written in PHP and uses the Python-based PySCeS-CBM for its linear solving capabilities. It comes with a comprehensive manual and a quick-start tutorial, and can be accessed online at http://f-a-m-e.org/.

Conclusions

With FAME, we present the community with an open source, user-friendly, web-based "one stop shop" for stoichiometric modeling. We expect the application will be of substantial use to investigators and educators alike.
Cox-2 gene overexpression in ureteral stump urothelial carcinoma following nephrectomy for renal cell carcinoma: a case report
Authors: Chang Wei-Pin , Chien Tsu-Ming , Wang Yu-Shiuan , Chiu Siou-Jin , Lee Mei-Hui , Chang Wei-Chiao , Chou Yii-Her , Hou Ming-Feng
Published: January 2012

Introduction

A primary ureteral stump tumor after a nephrectomy is rare; urothelial carcinoma of the ureteral stump after a nephrectomy for renal cell carcinoma is even rarer. A thorough review of the literature indicated that only seven cases have previously been reported. In this study, we report the first Taiwanese case of urothelial carcinoma of the ureteral stump after a nephrectomy. It is also the first female case in the literature. The relationship between inflammatory genes, medication history and ureteral stump carcinoma after a nephrectomy for renal cell carcinoma has not been reported.

Case presentation

A 72-year-old Asian Taiwanese women with chronic hepatitis C, liver cirrhosis and chronic kidney disease underwent a hand-assisted laparoscopic radical nephrectomy in 2001 due to renal cell carcinoma. Nine years later, she was diagnosed with ureteral stump urothelial carcinoma. Genetic and medication surveys were performed. Importantly, our patient had taken Chinese herbal drugs for more than 10 years and the inflammatory gene, Cox-2, was highly expressed in this patient. This is the first report to study the relationship between the Cox-2 gene and ureteral stump carcinoma after a nephrectomy for renal cell carcinoma.

Conclusion

Long-term multiple use of Chinese herbal drugs could be one of the important risk factors for developing urothelial cancer. Close functional coupling between Chinese herbal drugs, Cox-2 gene activation and urothelial cancer should be further investigated.
Migration of monocytes after intracerebral injection at entorhinal cortex lesion site
Authors: Kaminski Miriam , Bechmann Ingo , Pohland Martin , Kiwit Jürgen , Nitsch Robert , Glumm Jana
Published: January 2012

After axonal lesion in the CNS, intracerebrally injected green fluorescent monocytes migrate through the cribroid plate and subsequently accumulate in deep cervical lymph nodes.

The lack of classical lymph vessels within brain tissue complicates immune surveillance of the CNS, and therefore, cellular emigration out of the CNS parenchyma requires alternate pathways. Whereas invasion of blood-derived mononuclear cells and their transformation into ramified, microglia-like cells in areas of axonal degeneration across an intact BBB have been demonstrated, it still remained unclear whether these cells reside permanently, undergo apoptosis, or leave the brain to present antigen in lymphoid organs. With the use of ECL of mice and injection of GFP-expressing monocytes, we followed the appearance of injected cells in spleen and LNs and the migratory pathways in whole-head histological sections. Monocytes migrated from the lesion site to deep CLNs, peaking in number at Day 7, but they were virtually absent in spleen and in superficial CLNs and inguinal LNs until Day 21 after lesion/injection. In whole-head sections, GFP monocytes were found attached to the olfactory nerves and located within the nasal mucosa at 48 hpi. Thus, monocytes are capable of migrating from lesioned brain areas to deep CLNs and use the cribriform plate as an exit route.
Editorial: Tim-3 puts on the brakes
Authors: Anderson Ana Carrizosa
Published: January 2012

Discussion on how Tim-3 negatively regulates both innate and adaptive immune responses.
Comparative Effectiveness of Robotic Versus Laparoscopic Hysterectomy for Endometrial Cancer
Authors: Wright Jason D. , Burke William M. , Wilde Elizabeth T. , Lewin Sharyn N. , Charles Abigail S. , Kim Jin Hee , Goldman Noah , Neugut Alfred I. , Herzog Thomas J. , Hershman Dawn L.
Published: January 2012

Purpose

Use of robotics in oncologic surgery is increasing; however, reports of safety and efficacy are from highly experienced surgeons and centers. We performed a population-based analysis to compare laparoscopic hysterectomy and robotic hysterectomy for endometrial cancer.

Patients and Methods

The Perspective database was used to identify women who underwent a minimally invasive hysterectomy for endometrial cancer from 2008 to 2010. Morbidity, mortality, and cost were evaluated using multivariable logistic and linear regression models.

Results

We identified 2,464 women, including 1,027 (41.7%) who underwent laparoscopic hysterectomy and 1,437 (58.3%) who underwent robotic hysterectomy. Women treated at larger hospitals, nonteaching hospitals, and centers outside of the northeast were more likely to undergo a robotic hysterectomy procedure, whereas black women, those without insurance, and women in rural areas were less likely to undergo a robotic hysterectomy procedure (P < .05 for all). The overall complication rate was 9.8% for laparoscopic hysterectomy versus 8.1% for robotic hysterectomy (P = .13). The adjusted odds ratio (OR) for any morbidity for robotic hysterectomy was 0.76 (95% CI, 0.56 to 1.03). After adjusting for patient, surgeon, and hospital characteristics, there were no significant differences in the rates of intraoperative complications (OR, 0.68; 95% CI, 0.42 to 1.08), surgical site complications (OR, 1.49; 95% CI, 0.81 to 2.73), medical complications (OR, 0.64; 95% CI, 0.40 to 1.01), or prolonged hospitalization (OR, 0.85; 95% CI, 0.64 to 1.14) between the procedures. The mean cost for robotic hysterectomy was $10,618 versus $8,996 for laparoscopic hysterectomy (P < .001). In a multivariable model, robotic hysterectomy was significantly more costly ($1,291; 95% CI, $985 to $1,597).

Conclusion

Despite claims of decreased complications with robotic hysterectomy, we found similar morbidity but increased cost compared with laparoscopic hysterectomy. Comparative long-term efficacy data are needed to justify its widespread use.
MicroRNAs and their roles in aging
Authors: Smith-Vikos Thalyana , Slack Frank J.
Published: January 2012

MicroRNAs (miRNAs) are a class of short non-coding RNAs that bind mRNAs through partial base-pair complementarity with their target genes, resulting in post-transcriptional repression of gene expression. The role of miRNAs in controlling aging processes has been uncovered recently with the discovery of miRNAs that regulate lifespan in the nematode Caenorhabditis elegans through insulin and insulin-like growth factor-1 signaling and DNA damage checkpoint factors. Furthermore, numerous miRNAs are differentially expressed during aging in C. elegans, but the specific functions of many of these miRNAs are still unknown. Recently, various miRNAs have been identified that are up- or down-regulated during mammalian aging by comparing their tissue-specific expression in younger and older mice. In addition, many miRNAs have been implicated in governing senescence in a variety of human cell lines, and the precise functions of some of these miRNAs in regulating cellular senescence have helped to elucidate mechanisms underlying aging. In this Commentary, we review the various regulatory roles of miRNAs during aging processes. We highlight how certain miRNAs can regulate aging on the level of organism lifespan, tissue aging or cellular senescence. Finally, we discuss future approaches that might be used to investigate the mechanisms by which miRNAs govern aging processes.
18F-FDG PET/CT features of pulmonary sclerosing hemangioma
Authors: Lee Eugene , Park Chang Min , Kang Keon Wook , Goo Jin Mo , Kim Min A , Paeng Jin Chul , Lee Hyun Ju , Park Heae Surng , Chung Doo Hyun
Published: January 2012

Background

Pulmonary sclerosing hemangioma (PSH) has been reported to show increased FDG uptake and be potential false-positives on 18F-FDG PET/CT examination. However, it is still unclear whether the previously-reported high FDG uptake is a universal characteristic of PSH, and furthermore, there have been no investigations on what kind of radiologic or histologic features may have been related with its FDG uptake values.

Purpose

To investigate the 18F-FDG PET/CT features of pulmonary sclerosing hemangiomas (PSHs), and to evaluate the relating factors with their FDG uptake values.

Material and Methods

We identified 10 PSHs in eight patients who had a pathologic diagnosis and available antecedent 18F-FDG PET/CT images. 18F-FDG PET/CT images were investigated both qualitatively and quantitatively, along with their histopathologic features. Correlation between 18F-FDG PET features and radiologic as well as histopathologic features were also evaluated.

Results

Mean diameter of the 10 PSHs in our study was 16.9 mm ± 6.26 (range 5-25 mm). Four tumors showed intense uptake, and four tumors showed moderate uptake on 18F-FDG PET/CT scans. In the remaining two tumors, there were no significant FDG uptakes. The SUVmax of tumors ranged from 0.60-4.7 (median 2.30; 2.51 ± 1.42), and was significantly correlated with the tumor size (r = 0.754, P = 0.012) and three out of four tumors ≥2 cm (75%) showed intense FDG uptake and their SUVmax values were greater than 2.5. Immunohistochemical results for GLUT-1, GLUT-4, and Ki-67 and other pathologic features were not correlated with the tumors’ FDG uptake.

Conclusion

The majority of PSHs show increased FDG uptakes, and their SUVmax values are significantly correlated with their tumor size. PSH ≥2 cm can frequently be falsely interpreted as malignancy in FDG-PET/CT. Further studies with large study population are warranted to confirm our observations.
Left-sided ventricular cardiomyopathy with minimal right ventricular involvement
Authors: Kodikara Sarathchandra
Published: January 2012

Left-sided ventriclular arrhythmogenic cardiomyopathy is rare and represents a rather different expression of the arrhythmogenic right ventricular (RV) cardiomyopathy (ARVC). Among sudden cardiac deaths, ARVC plays a significant role. ARVC is considered as a cardiomyopathy of unknown aetiology that primarily involves the right ventricle (RV) and is characterized by progressive replacement of myocytes by fibro-fatty tissue, complicating a spectrum of arrhythmias. Predominant ARVC with left ventricular (LV) involvement is also reported. The LV variant of arrhythmogenic cardiomyopathy with minimal or no RV involvement is rare. A 31-year-old previously healthy young man, without a significant family history, was found dead in bed. Autopsy revealed an enlarged heart and asymmetrical LV hypertrophy with widely patent coronary arteries. LV myocardium demonstrated evidence of prominent epicardial fibro-fatty tissue that is predominantly fatty in nature and infiltrates into the myocardium. Microscopy of the LV free wall showed fibro-fatty tissue infiltration into the epicardial aspect of the LV that extends well into the mid-myocardium. A moderate to marked degree of interstitial fibrous tissue deposition was noted about adipocytes and cardiomyocytes. There was no evidence of chronic ischaemic changes or of significant myofibre disarray. The RV showed minimal fibro-fatty infiltration with normal myocytes. This report highlights a rare case which confirms previous observations that the LV variant of arrhythmogenic cardiomyopathy could occur with minimal or no involvement of the RV. Further studies are required in this context to elicit the spectrum and the exact nature of this disease.
Locational characteristics of the increasing number of forensic autopsy cases in Kyoto, Japan
Authors: McLean Stuart , Nanba Hiroko , Ikegaya Hiroshi
Published: January 2012

In Japan, the definition of unnatural death is not prescribed in law. However, a legal judgment recently defined unnatural death as all deaths, excluding natural deaths and deaths from diseases. Legally, unnatural deaths must be reported to the police. In the case of a reported death being considered as suspicious by the police, a forensic autopsy is required. The number of autopsies and the autopsy rate in Japan and Kyoto has increased over the last 10 years. Using data collected from 221 autopsy cases between 2008 and 2010 in Kyoto, Japan, the characteristics of locations where autopsy cases were discovered were analysed to identify reasons for the increase in autopsy numbers. It was found that factors including amount of human interaction and socioeconomic factors may help to explain the statistically significant correlations found.
In Situ Raman Spectroscopy: A Process Analytical Technology Tool to Monitor a De-protection Reaction Carried Out in Aqueous Solution
Authors: Clegg Ian M. , Pearce John , Content Stéphane
Published: January 2012

The application of in situ Raman spectroscopy at small scale (maximum 80 mL) during the development of a manufacturing process is disclosed. The reaction was run in aqueous solution between ambient and 100 °C. Raman spectroscopy has proven to be a viable method to track the reaction. Three distinct phases could be followed: dissolution of the starting material, production of a reactive intermediate, and then subsequent conversion of that intermediate to form product. The objective of the work was to confirm the presence of a reactive intermediate and this could only be carried out via in situ spectroscopy as the intermediate was known to be unstable. Toward the end, the reaction passes though several neutralization points and these are consistent with changes in the spectra. Comparison of data obtained at an illumination wavelength of 998 nm with that obtained at 785 nm is also disclosed. The data obtained at shorter wavelength was contaminated by reasonably strong fluorescence, whereas the data obtained at 998 nm was free of fluorescence. An unexpected observation from this work was that the reaction time was much shorter than expected and this work was key in showing that a reduction in batch cycle time was possible during commercial manufacture.
Noise Characterization in Circular Dichroism Spectroscopy
Authors: DiNitto Julie M. , Kenney John M.
Published: January 2012

Circular dichroism (CD), defined as the difference in absorption between left and right circularly polarized light, is used to spectroscopically study the structures of chiral materials. In this article, various methodologies are presented for characterizing the performance of CD spectrometers to determine (1) experimental conditions for optimal data collection, (2) noise characteristics dependent on machine parameters, (3) the relative significance of spectral data as a function of detector gain, and (4) stray light and dark current as a function of wavelength. The results of case studies of two commercial CD spectrometers (specifically, Jasco J810 and J815) are described. The analyses show that the variation of CD signal is Poisson distributed and hence can be considered shot noise. Also, optimum scan parameters are established and a weighting function of CD data significance is produced so that wavelength-dependent gain (as determined by the high tension, HT, voltage applied to the photomultiplier tube, PMT, detector) can be accommodated. Lastly, the amount of stray light and dark current for the photomultiplier tube is determined. Though specific to the Jasco CD spectrometers characterized in this study, it is expected that all CD spectrometers exhibit similar behavior and the methodology described here can be usefully applied to characterize CD spectrometers independent of manufacturer.
Concentration Measurements in Ionic Liquid–Water Mixtures by Mid-Infrared Spectroscopy and Indirect Hard Modeling
Authors: Viell Jörn , Marquardt Wolfgang
Published: January 2012

An analytical method for the quantitative characterization of binary mixtures of water and ionic liquids (ILs) is presented. Mid-infrared (mid-IR) spectroscopy in combination with indirect hard modeling (IHM) is employed to quantify the water content in 1-butyl-3-methylimidazolium chloride (BMIMCl), 1,3-dimethylimidazolium dimethylphosphate (DMIMDMP), and 1-ethyl-3-methylimidazolium acetate (EMIMAc). Despite significant nonlinear shifts of the spectral bands, a good spectral fit with calibration errors of less than 2.3 wt % can be achieved almost over the whole concentration range. A profound analysis of the spectral models including peak assignment substantiates the physico-chemical foundation of the spectral models. Furthermore, the shift of peak functions in the spectral models is shown to provide a measure of molecular interaction in IL–water mixtures, which can also be utilized quantitatively. The vibrational bands of the water dipole reveal differences in the strength of hydrogen bonding with water in the IL studied. These properties of the spectral hard models demonstrate their quantitative analytical potential and set the stage for multiway calibration in comprehensive reaction monitoring in these highly interacting mixtures of IL and water.
Chemiluminescent Identification and Quantification of Artemisinin and Relevant Sesquiterpene Lactone Derivatives
Authors: Bowles David J. , Olson Andrew S. , Hodges Neal H. , Heglund Daniel L. , Vargas Roberto L. , Williams Scott A.
Published: January 2012

A simple, sensitive, and rapid chemiluminescence method was developed for the detection and quantification of selected derivatives of artemisinin. It was found that the chemiluminescence (CL) signal resulting from the alkaline luminol reaction of the artemisinin derivatives in the presence of hematin was linear over a wide concentration range. We report results that suggest that a visual test or a test involving digital image capture may be used in addition to a field-ready instrumental approach to combat drug counterfeiting of malarial therapies.
Single-Molecule Enzyme Dynamics of Monomeric Sarcosine Oxidase in a Gold-Based Zero-Mode Waveguide
Authors: Zhao Jing , Branagan Sean P. , Bohn Paul W.
Published: January 2012

The localization of optical fields is a powerful method of reducing spectroscopic background signals, enabling studies of single fluorescent molecules. Zero-mode waveguides (ZMWs) strongly confine optical fields to zeptoliter (zL, 10−21 L) volumes and can be coupled with fluorescence microscopy to study the dynamics of single enzyme molecules due to their excellent optical confinement, precise positioning, and massive parallelism. The experiments described here exploit arrays of gold-based (Au-based) nanopores derivatized with single copies of the redox enzyme monomeric sarcosine oxidase (MSOX). MSOX contains a covalently bound flavin adenine dinucleotide (FAD) cofactor, which is highly fluorescent in the oxidized state and dark in the reduced state, thus producing a characteristic on–off fluorescence signal synchronous with transitions between oxidation states. Although aluminum (Al) is the common choice for the metallic overlayer in ZMW construction, Au is used here to access its unique surface-binding chemistry. In particular, the signal-to-noise ratio is improved for Au-based ZMWs by selective Au passivation. For MSOX reactions involving both the nominal substrate (sarcosine) and an analogous substrate (proline), statistical analysis of single-molecule temporal trajectories reveals the static heterogeneity of single-enzyme reaction rates, but no dynamic disorder. In addition, the single-molecule data confirm the independence of reduction and oxidation reactions. These structures open the way for systematic studies of the effect of molecular crowding on enzyme dynamics.
Adverse Psychosocial Working Conditions and Poor Quality of Life among Financial Service Employees in Brazil
Authors: Silva Luiz Sergio , Barreto Sandhi Maria
Published: January 2012

Adverse Psychosocial Working Conditions and Poor Quality of Life among Financial Service Employees in Brazil: Luiz Sergio SILVA, et al. School of Medicine, Preventive Medicine, Universidade Federal de Minas Gerais, Brazil—

Objectives

Workers in the financial services sector are exposed to great stress at work. This study investigates whether exposure to adverse psychosocial work conditions is independently associated with poor health‐related physical and mental quality of life among financial services workers.

Methods

We studied a nationwide representative sample of 2,054 workers of a large Brazilian state bank in 2008. Adverse psychosocial work conditions were investigated by the Effort‐reward imbalance (ERI) scale and the Job content questionnaire (JCQ). Health‐related quality of life (HRQL) was assessed using the Medical Outcomes Study Short‐Form General Health Survey (SF‐12). Poor mental and physical HRQL was defined by the lowest quartiles of the SF‐12 final score distributions. Associations were investigated using multiple logistic regression analysis.

Results

In the multivariate analysis, exposures to low control and lack of social support at work (JCQ) were associated with poor HRQL in the physical domain. Increasing effort‐reward imbalance and overcommitment (ERI), on the other hand, were associated with poor HRQL in the mental domain, with a significant statistical trend. Overcommitment was also associated with poor physical HRQL.

Conclusion

The results suggest that exposure to adverse psychosocial work conditions has a negative impact on both domains of HRQL among financial service workers. They also indicate that ERI and DC models capture different aspects of job strain.
A Decision-Tree Approach to Cost Comparison of Newborn Screening Strategies for Cystic Fibrosis
Authors: Wells Janelle , Rosenberg Marjorie , Hoffman Gary , Anstead Michael , Farrell Philip M.
Published: January 2012

OBJECTIVE:

Because cystic fibrosis can be difficult to diagnose and treat early, newborn screening programs have rapidly developed nationwide but methods vary widely. We therefore investigated the costs and consequences or specific outcomes of the 2 most commonly used methods.

METHODS:

With available data on screening and follow-up, we used a simulation approach with decision trees to compare immunoreactive trypsinogen (IRT) screening followed by a second IRT test against an IRT/DNA analysis. By using a Monte Carlo simulation program, variation in the model parameters for counts at various nodes of the decision trees, as well as for costs, are included and applied to fictional cohorts of 100 000 newborns. The outcome measures included the numbers of newborns given a diagnosis of cystic fibrosis and costs of screening strategy at each branch and cost per newborn.

RESULTS:

Simulations revealed a substantial number of potential missed diagnoses for the IRT/IRT system versus IRT/DNA. Although the IRT/IRT strategy with commonly used cutoff values offers an average overall cost savings of $2.30 per newborn, a breakdown of costs by societal segments demonstrated higher out-of-pocket costs for families. Two potential system failures causing delayed diagnoses were identified relating to the screening protocols and the follow-up system.

CONCLUSIONS:

The IRT/IRT screening algorithm reduces the costs to laboratories and insurance companies but has more system failures. IRT/DNA offers other advantages, including fewer delayed diagnoses and lower out-of-pocket costs to families.
Nasal Continuous Positive Airway Pressure With Heliox in Preterm Infants With Respiratory Distress Syndrome
Authors: Colnaghi Mariarosa , Pierro Maria , Migliori Claudio , Ciralli Fabrizio , Matassa Piero Giuseppe , Vendettuoli Valentina , Mercadante Domenica , Consonni Dario , Mosca Fabio
Published: January 2012

OBJECTIVE:

To assess the therapeutic effects of breathing a low-density helium and oxygen mixture (heliox, 80% helium and 20% oxygen) in premature infants with respiratory distress syndrome (RDS) treated with nasal continuous positive airway pressure (NCPAP).

METHODS:

Infants born between 28 and 32 weeks of gestational age with radiologic findings and clinical symptoms of RDS and requiring respiratory support with NCPAP within the first hour of life were included. These infants were randomly assigned to receive either standard medical air (control group) or a 4:1 helium and oxygen mixture (heliox group) during the first 12 hours of enrollment, followed by medical air until NCPAP was no longer needed.

RESULTS:

From February 2008 to September 2010, 51 newborn infants were randomly assigned to two groups, 24 in the control group and 27 in the heliox group. NCPAP with heliox significantly decreased the risk of mechanical ventilation in comparison with NCPAP with medical air (14.8% vs 45.8%).

CONCLUSIONS:

Heliox increases the effectiveness of NCPAP in the treatment of RDS in premature infants.
Statistical Analysis Based on Information Obtained from Inspection in Line to Forecast Future Land Pipeline Damage
Authors: González-Domínguez J. L. , Padilla-Pérez D. A. , Hernández-Mejía S. L. , Adame-González M. A.
Published: January 2012

Oil industry is very strategic for any country. Not only for their market share and their budgets, but also for the critical infrastructure interdependences that creates. Considering statistics and fractal geometry as a support for analysis, interpretation of data and as an aid in taking decisions, this paper deals with data obtained in 1994 and 2004 from the inspection of the onshore pipelines in Mexico. Making use of software Benoit and ITSM-2000, the time series were found to have a fractal behavior. Further analysis and contrast with a previous research base on artificial neural networks was also accomplished. As a result it was obtained a forecast for 2014, based on the sum of the time series of data.
Preparation and Characterization of Aluminum Lithium Hydroxide Carbonate Hydrate Obtained From Basic Aluminum Sulfate
Authors: Soto César A. C. , Delgado Aurora P. , Ramírez Esthela R. , Zamudio Veridiana R.
Published: January 2012

Aluminum lithium hydroxide carbonate hydrate, also known as Al-Li double hydroxide or Al-Li hydrotalcite-like compound [Al2Li(OH)6]2CO3•nH2O, was prepared from basic aluminum sulfate. This compound was prepared by precipitation in homogeneous solution of an aluminum bisulfite solution. A sodium aluminate aqueous solution was prepared by dissolving basic aluminum sulfate in 1M sodium hydroxide. The Al-Li double hydroxide was obtained after addition of lithium carbonate satured solution to the sodium aluminate solution, at 60 °C. The synthesized powder was characterized by thermal analysis (TG, DTG and DTA), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). By this method crystalline Li-Al hydrotalcite like compound with composition near to Al4Li2(OH)12CO3 •3H2O was obtained.
Study of the Impact of Quenching Process Parameters in High Dimension Rings of Steel AISI 4140
Authors: Márquez C. , Martínez E. , Cárdenas J. , Saldívar O. , Rodríguez J. , Fernández F. , Pérez A.
Published: January 2012

Manufacturing of high dimension steel rings impose several technological challenges. The lack of understanding of the principles and practices of quenching can result in inadequate hardness, excessive distortion or scrapping of costly machined components. This paper presents the results of an analytical study of the parameters of the quenching operation, among them the fluid dynamics of the agitation in the quenching media. Velocity components of the fluid were measured using an anemometer inside the quenching tank. Uniformity of agitation is compared with a Computational Fluid Dynamics (CFD) simulation. The CFD results revealed the impact of quench tank design, configuration and operation of impellers.
Characterization of Metallurgical Defects in the Melt Zone of 304L Steel Tubes Manufactured by GTAW Process
Authors: Ruíz-Mondragón J.J. , Acevedo-Dávila J. , García-Vázquez F. , Hdz-García H.M.
Published: January 2012

This study consisted of the characterization of longitudinal cracking pattern observed in weld joint in the manufacture of 304L steel pipelines with thin wall thickness by GTAW process. These tubes are used in food and automotive industries. The cracks grown in the liquid-solid interdendritic zones at high temperatures. It was found that the cracks are associated with change on solidification mode and presence of the holes produced by shrinkage. The change in the solidification mode was associated with the presence of second phase particles. The results suggest that the formation of cracks is promoted by increasing current during the welding although the heat input is constant.
Phosphorous and Boron Incorporation and its Effect on Optical Properties of Ge:H and Si0.01Ge0.99:HFilms Deposited by LF PECVD
Authors: Delgadillo Nery , Kosarev Andrey , Torres Afonso , Garcia Lancelot , Gonzales Brian
Published: January 2012

Deposition conditions that provided low absorption related to both band tail and deep localized states have been found for both materials Ge:H and Si1YGeY:H. Phosphorous incorporation on Si0.01Ge0.99:H films and boron incorporation on Ge:H films were deposited by low frequency plasma-enhanced chemical vapour deposition (LF PECVD). The phosphorous incorporation in solidphase was observed to preferential with the increase of the doping in the gas phase to 2.5 %, and 2.5% to 4% was observed preferential Si0.01Ge0.99 film, boron incorporation in solid phase increase linearly with the increase of the doping gas phase. The content of solid phase was characterized by Secondary ion mass spectrometry (SIMS) profiling. Hydrogen concentration in the films was determined from Fourier transform infrared spectroscopy (FTIR) and SIMS measurements. Optical measurements provided optical gap, localized states, and band tail. A significant reduction of both band tail and deep localized states were observed at boron incorporation in solid phase = 0.004% on Ge:H films and the same were observed at phosphorous incorporation in solid phase = 0.29% on Si0.01Ge0.99:H films.
Microstructural Evolution of High Dimension Rings of Steel AISI 4140
Authors: Martínez E. , Márquez C. , Rodríguez J. , Fernández F. , Cárdenas J. , Pérez A.
Published: January 2012

This paper presents the results of the analytical study of the microstructural evolution of forged and rolled rings with a diameter greater than 2 meters, since the raw material, set-up forgings, ring rolling and heat treatments, including normalizing, quenching and tempering. Also, great care will be taken on the chemical micro-segregation. Four rings, were instrumented with 20 thermocouples each one in order to follow the thermal profile during heating and quenching. Cooling rates will be used to predict the microstructure developed under the different heat treatments and it will be compared at different positions inside the rings. It can be seen that the cooling curves obtained show no presence of soft phases, as shown in the microstructures in the figure shown below. With the results of microstructure obtained, which show martensitic structure to a greater extent, it meets the desirable mechanical properties, which are shown below.
Microstructural Study of as-cast Fe-Si Alloys. Effect of Percentage of Silicon
Authors: González F. María G. , García H. José A. , Balandra A. , Aranda. V.
Published: January 2012

Silicon steels are materials used in construction of electric motors and transformers. Silicon is an effective element to improve the electrical and magnetic properties. During the solidification stage is defined the distribution of solute on the solid as segregation or coring. This paper researched the effect of the percentage of silicon on the microstructure and segregation profiles of the Fe-0.5wt%Si, Fe-1.5wt%Si and Fe-3wt%Si cast alloys. The samples were metallographically prepared by conventional techniques. The concentration of silicon in grain boundary regions was carried out by scanning electron microscopy (SEM) with EDS-WDS microanalysis, the morphological changes of the grain as a function of silicon was evaluated by optical microscopy. Experimental microsegregation patterns showed significant difference from the Scheil model and greater agreement with this model when considering convective-diffusive conditions. The microstructural study revealed discrepancies with the solidification pattern governed by the solidification interval.
Grain Refinement and Mechanical Properties Enhancement in Cross Roll Rolled Pure Copper
Authors: Song Kuk Hyun , Kim Han Sol , Kim Won Yong
Published: January 2012

To evaluate the microstructures and mechanical properties in cross-roll rolled pure copper, comparing with conventionally rolled materials, this work was carried out. Pure copper (99.99 mass%) sheets with thickness of 5 mm were cold rolled to 90% thickness reduction by cross-roll rolling (CRR) and subsequently annealed at 400 °C for 30 min. Also, to analyze the grain boundary character distributions (GBCDs), electron back-scattered diffraction (EBSD) technique was employed. As a result, the cold rolled and annealed materials consisted of significantly refined grains than that of the initial material (100 μm). Especially, the CRR processed material showed more refined grain size (6.5 μm) in average than that (9.8 μm) of conventional rolling (CR). These grain refinements directly affected an increase in mechanical properties. Furthermore, the texture development in CRR processed material, in which <112> grains were densely distributed in the normal direction (ND), was more effective to enhance the yield strength.
Preparation of Pd /α–Al2O3 and Pd-Ag/α–Al2O3 Membranes by Electroless Plating and Permeation Measurements
Authors: Ortiz-Martínez L. , Torres-Rodríguez M. , Gutiérrez-Arzaluz M.
Published: January 2012

In this work, the synthesis of dense Pd/α–Al2O3 and Pd-Ag/α–Al2O3 ceramic composite membranes was done through the sequential electroless plating technique of Pd and Ag. The precursors are solutions of PdCl2 and AgNO3 and N2H4 salts, as reducing agent. The membranes were characterized by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Energy Dispersive Spectroscopy (EDS). The permeation tests of H2 and N2 was carried out at 20 psi of pressure and at 25°C, resulted πH2=5.2x10-9 mol H2/m2·s·Pa and πN2=8.2x10-10 mol N2/m2·s·Pa.
Characterization of the Stainless Steel Corrosion Kinetic By EIS
Authors: Galvan-Martinez R. , Flores-Cocuyo M. , Orozco-Cruz R. , Contreras A.
Published: January 2012

An electrochemical study was carried out in order to obtain the effects of the turbulent flow condition on the stainless steel corrosion immersed in natural seawater using an electrochemical corrosion technique like electrochemical impedance spectroscopy (EIS). A three-electrode electrochemical glass cell was used to obtain the electrochemical measures, where a cylinder of the AISI 410 stainless steel was used as working electrode, a saturated calomel electrode as reference electrode and a synthesised graphite rod as auxiliary electrode. 24 hours was the total exposure time. In order to control the hydrodynamic conditions a rotating cylinder electrode (RCE) was used and, a scanning electron microscope (SEM) was used in order to obtain the superficial analyses of the metallic surface after tests. The results of the electrochemical techniques shown that at 1000 rpm of the rotation speed, the corrosion rate (CR) increased as the exposure time also increased. In additions, in the other rotations speed (2000, 3000 and 5000 rpm), the CR was affected by the corrosion products formed on metallic surface. t is important to point out that the corrosion morphology found in the steel sample was localized corrosion.
Synthesis of Silver Nanostructures by the Polyol Method and their Statistical Analysis Using Design of Experiments
Authors: Pérez Jaime E. , Arauz Adriana B. , García Luis A. , Rodríguez José L.
Published: January 2012

In this work we present the bases to perform investigation on the effects on the morphology and size of nanostructures of silver, owed to the modification of synthesis factors in a polyol process such as temperature, concentration, time of reaction, injection speed and time of injection. It is claimed that control over Ag nanostructures shape could be improved and significant information about the synthesis process can be obtained. The design of experiments was done aimed to obtain useful information about how to yield as much as possible specific structures of interest.