bluuebunny/crossref_metadata_2025 huggingface dataset:
Solar thermal power plant simulation
Authors: Abutayeh Mohammad , Goswami Yogi D. , Stefanakos Elias K.
Published: April 2012

A detailed model of a real solar thermal power plant has been built using a steady‐state power plant simulation software. The plant includes numerous parabolic trough collectors tracking the sun on a single axis. A heat transfer fluid flows in the focal line of the troughs collecting solar heat, which is transferred to high pressure water from the power block generating high pressure steam that is sent to a steam turbine to generate electricity via an attached generator. In addition, a spreadsheet has been formulated to work in tandem with the simulation software to model the daily operation of the plant. The spreadsheet is populated with 1 min increment time‐stamped operating data where computations are carried out to estimate the thermal energy contribution of the warm up and the cool down transient operations. Solar radiation offsets are calculated based on those transient heats and then incrementally added to the real‐solar radiation data to produce effective solar radiation records. Data columns of the effective solar radiation, ambient temperature, humidity, wind speed, time of day, day of year, and other geographical and optical constants are incrementally passed from the spreadsheet to the simulation program, which executes and outputs results back into the same spreadsheet. Simulation results matched well with plant data including data collected during warm up and cool down transient operations. © 2012 American Institute of Chemical Engineers Environ Prog, 32: 417‐424, 2013
Effects of cadmium and arsenic on Pteris vittata under hydroponic conditions
Authors: Drava Giuliana , Roccotiello Enrica , Minganti Vincenzo , Manfredi Alice , Cornara Laura
Published: April 2012

Pteris vittata is known to hyperaccumulate arsenic, and a large number of studies on this fern species can be found in the literature aimed at evaluating its behavior when coexposed to other toxic elements. In the present study, P. vittata was treated with different concentrations of As and/or Cd in a hydroponic system, that is, under complete bioavailability of the elements, with the objective of investigating the effects of these two elements and their interactions. The response of the plant was evaluated by measuring As, Cd, P, and Ca concentrations in different parts of the plant. Moreover, the symptoms of phytotoxicity were assessed in terms of biomass reduction and loss of photosynthetic efficiency related to necrosis of pinnae. The concentrations of As and Cd measured in the fronds and the root system were significantly dependent on the treatment, whereas P and Ca concentrations were not affected. Interaction effects between As and Cd were observed, with maximum toxicity symptoms after treatment with both elements. This could affect the potential use of this fern for phytoremediation. Although As treatment produced a significant effect on leaves (e.g., chlorosis and necrosis), Cd treatment produced a stronger negative impact on plant health, reducing significantly the biomass and photosynthetic efficiency. Environ. Toxicol. Chem. 2012;31:1375–1380. © 2012 SETAC
Suppressive subtractive hybridization libraries prepared from the digestive gland of the oyster Crassostrea brasiliana exposed to a diesel fuel water-accommodated fraction
Authors: Lüchmann Karim Hahn , Mattos Jacó Joaquim , Siebert Marília Nardelli , Dorrington Tarquin Stephen , Toledo-Silva Guilherme , Stoco Patricia Hermes , Grisard Edmundo Carlos , Bainy Afonso Celso Dias
Published: April 2012

Diesel fuel can cause adverse effects in marine invertebrates by mechanisms that are not clearly understood. The authors used suppressive subtractive hybridization to identify genes up- and downregulated in Crassostrea brasiliana exposed to diesel fuel. Genes putatively involved in protein regulation, innate immune, and stress response, were altered by diesel challenge. Three genes regulated by diesel were validated by quantitative real-time polymerase chain reaction. This study sheds light on transcriptomic responses of oysters to diesel pollution. Environ. Toxicol. Chem. 2012;31:1249–1253. © 2012 SETAC
Methylmercury in mosquitoes around a large coal-fired power plant in central Ohio
Authors: Konkler Matthew J. , Hammerschmidt Chad R.
Published: April 2012

Emissions from coal-fired power plants are the major anthropogenic source of mercury (Hg) in the environment. Because emitted Hg can be deposited near the source, concerns arise about the effects of coal-burning facilities on levels of toxic methylmercury (MeHg) in biota near such sources. We investigated the potential impact of a large Hg-emitting (450 kg in 2005) coal-fired power station in Conesville, Ohio, on MeHg levels in adult mosquitoes near the plant. In July 2010, mosquitoes were sampled at 23 locations within a 60-km radius of the plant and at three reference sites distant from major combustion sources of Hg. Nearly all of the Hg in mosquitoes appeared in the form of MeHg (mean = 91%). Concentrations of MeHg in mosquitoes were unrelated to either distance or direction from the Conesville plant and did not differ from those at the three reference sites. Moreover, measured levels of MeHg in mosquitoes near Conesville are in good agreement with those predicted from an empirical relationship to wet atmospheric Hg fluxes alone. This suggests that either little of the Hg emitted from the Conesville plant is deposited locally or near-source deposition of Hg does not have a significant impact on MeHg in mosquitoes and, by extension, other insects with similar life histories in the local food web. Environ. Toxicol. Chem. 2012; 31: 1657–1661. © 2012 SETAC
Is CCS a fully fledged business proposition or an interesting experiment?
Authors: Cozier Muriel
Published: April 2012

As delegates have been meeting for the first carbon capture and storage (CCS) conferences of 2012, the theme that seems to have emerged in the early stages of this year is: what next for CCS? Muriel Cozier provides an insight into the minefield of some of the political and financial challenges facing the commercialization and wide‐scale deployment of CCS projects.
Synthesis and reactivity of substituted alkoxymethylphosphonites and their derivatives
Authors: Prishchenko Andrey A. , Livantsov Mikhail V. , Novikova Olga P. , Livantsova Ludmila I. , Petrosyan Valery S.
Published: April 2012

Alkoxy‐substituted methylphosphonites and their derivatives are prepared using an organomagnesium method of synthesizing the organophosphorus compounds and alkoxymethylation of various PH acids and their derivatives. Also, certain properties of these promising compounds as important precursors of new functionalized organophosphorue compounds with alkoxymethyl fragments are presented. © 2012 Wiley Periodicals, Inc. Heteroatom Chem 23:281–289, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.21015
An approach to 1,2‐dihydro‐1,4,2‐ benzodiazaphosphinines
Authors: Marchenko Anatoliy P. , Koidan Georgiy. N. , Huryeva Anastasia N. , Merkulov Anatoliy S. , Kostyuk Aleksandr N.
Published: April 2012

A convenient approach to 1,2‐dihydro‐1,4,2‐benzodiazaphosphinines was proposed. The readily available 2‐trichloromethyl‐1,3‐dihydrobenzo[1,3,2]diazaphosphole‐2‐oxide (sulfide or selenide) was found to undergo a rearrangement into the targeted benzodiazaphosphinines by the action of dimethylamide lithium. © 2012 Wiley Periodicals, Inc. Heteroatom Chem 23:309–313, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.21018
Race- and gender-related variation in natural killer p46 expression associated with differential anti-hepatitis c virus immunity
Authors: Golden-Mason Lucy , Stone Amy E.L. , Bambha Kiran M. , Cheng Linling , Rosen Hugo R.
Published: April 2012

Major racial and gender differences have been documented in the natural history and treatment responses of chronic hepatitis C virus (HCV) infection; however, distinct mechanisms have remained enigmatic. We hypothesized that racial- and gender-related differences in natural killer (NK) cell populations may explain altered natural history and treatment responses. Our study cohort consisted of 29 African-American (AA; 55% male) and 29 Caucasian-American (CA; 48% male) healthy uninfected control subjects. Multiparameter flow cytometric analysis was used to characterize levels, phenotype with respect to 14 NK receptors, and lymphokine-activated killing (LAK) function. Gene expression was assessed by real-time reverse-transcriptase polymerase chain reaction after 6-hour

in vitro

stimulation with Toll-like receptor (TLR) ligands. The ability to control HCV infection was assessed in the Huh-7.5/JFH-1 coculture system. NK expression of natural cytotoxicity receptor NKp46 was strongly associated with CA race and female gender and correlated positively with LAK activity (

P

= 0.0054). NKp46high NKs were more efficient at controlling HCV than their NKp46low counterparts (

P

< 0.001). Similarly, ligation of NKp46 on isolated NK cells resulted in a significant reduction in the HCV copy number detected in Huh-7.5/JFH-1 coculture (multiplicity of infection: 0.01) at an effector:target ratio of 5:1 (

P

< 0.005). After TLR stimulation, genes involved in cytotoxicity, but not cytokine genes, were significantly up-regulated in NKp46high NKs. Cytokine stimulation (interleukin [IL]-12 and IL-15) demonstrated that NKp46high NK cells have significantly higher interferon-gamma production than NKp46low cells. TLR stimulation significantly induced degranulation as well as tumor necrosis factor alpha (TNF-α)-related apoptosis-inducing ligand, Fas, and TNF-α protein expression in NKp46high NKs. NKp46 ligand was induced on HCV-infected hepatocytes.

Conclusions

: NKp46 expression may contribute to differential HCV responses. NKp46 expression correlates with anti-HCV activity

in vitro

and thus may prove to be a useful therapeutic target. (Hepatology 2012)
Serine protease hepsin regulates hepatocyte size and hemodynamic retention of tumor cells by hepatocyte growth factor signaling in mice
Authors: Hsu Yu-Chen , Huang Hsiang-Po , Yu I-Shing , Su Kang-Yi , Lin Shu-Rung , Lin Wei-Chou , Wu Hua-Lin , Shi Guey-Yueh , Tao Mi-Hua , Kao Cheng-Heng , Wu Yao-Ming , Martin Patricia E. , Lin Shih-Yao , Yang Pan-Chyr , Lin Shu-Wha
Published: April 2012

The liver architecture plays an important role in maintaining hemodynamic balance, but the mechanisms that underlie this role are not fully understood. Hepsin, a type II transmembrane serine protease, is predominantly expressed in the liver, but has no known physiological functions. Here, we report that hemodynamic balance in the liver is regulated through hepsin. Deletion of hepsin (hepsin−/−) in mice resulted in enlarged hepatocytes and narrowed liver sinusoids. Using fluorescent microbeads and antihepsin treatment, we demonstrated that metastatic cancer cells preferentially colonized the hepsin−/− mouse liver as a result of the retention of tumor cells because of narrower sinusoids. The enlarged hepatocytes expressed increased levels of connexin, which resulted from defective prohepatocyte growth factor (pro-HGF) processing and decreased c-Met phosphorylation in the livers of hepsin−/− mice. Treatment of hepsin−/− mice with recombinant HGF rescued these phenotypes, and treatment of wild-type mice with an HGF antagonist recapitulated the phenotypes observed in hepsin−/− mice.

Conclusion:

Our findings show that the maintenance of hepatic structural homeostasis occurs through HGF/c-Met/connexin signaling by hepsin, and hepsin-mediated changes in liver architecture significantly enhance tumor metastasis to the liver.
Pentoxifylline decreases oxidized lipid products in nonalcoholic steatohepatitis: New evidence on the potential therapeutic mechanism
Authors: Zein Claudia O. , Lopez Rocio , Fu Xiaoming , Kirwan John P. , Yerian Lisa M. , McCullough Arthur J. , Hazen Stanley L. , Feldstein Ariel E.
Published: April 2012

Pentoxifylline (PTX) improved the histological features of nonalcoholic steatohepatitis (NASH) in a recent randomized placebo-controlled trial. However, the underlying mechanism responsible for the beneficial effects of PTX in NASH remains unidentified. A key role of lipid oxidation in the pathogenesis and progression of NASH has been established. PTX is known to decrease free-radical-mediated oxidative stress and inhibit lipid oxidation. The primary aim of this study was to evaluate the effects of PTX on levels of lipid oxidation products in patients with NASH. Levels of multiple structurally specific oxidized fatty acids including hydroxy-octadecadienoic acids (HODEs), oxo-octadecadienoic acids (oxoODEs), and hydroxy-eicosatetraenoic acids (HETEs) were quantified by mass spectrometry in plasma obtained at baseline and at study completion in patients who completed 1 year of therapy with PTX or placebo in a randomized controlled trial. Therapy with PTX resulted in significant decreases in 9-HODE and 13-oxoODE, oxidized lipid products of linoleic acid (LA) linked to histological severity in nonalcoholic fatty liver disease. Similarly, PTX therapy was associated with significant decreases in 8-HETE, 9-HETE, and 11-HETE compared to placebo. Statistically significant correlations were demonstrated between the decrease in HODEs and oxoODEs and improved histological scores of fibrosis and between the decrease in HETEs and improved lobular inflammation.

Conclusion

: Therapy with PTX compared to placebo was associated with a significant reduction of oxidized fatty acids. This novel evidence supports that the beneficial effects of PTX in patients with NASH are likely partly mediated through decreasing lipid oxidation, largely free-radical-mediated lipid oxidation. Additionally, this is the first report on the link between decreased oxidized lipid products and improved histological disease in the setting of a therapeutic trial in NASH. (Hepatology 2012)
Subset of Suz12/PRC2 target genes is activated during hepatitis B virus replication and liver carcinogenesis associated with HBV X protein
Authors: Studach Leo L. , Menne Stephan , Cairo Stefano , Buendia Marie Annick , Hullinger Ronald L. , Lefrançois Lydie , Merle Philippe , Andrisani Ourania M.
Published: April 2012

Chronic hepatitis B virus (HBV) infection is a major risk factor for developing liver cancer, and the HBV X protein (pX) has been implicated as a cofactor in hepatocyte transformation. We have shown that HBV replication as well as

in vitro

transformation by pX are associated with induction of the mitotic polo-like kinase 1 (Plk1) and down-regulation of the chromatin remodeling components Suz12 and Znf198. Herein, we demonstrate the same inverse relationship between Plk1 and Suz12/Znf198 in liver tumors from X/c-myc bitransgenic mice and woodchuck hepatitis virus (WHV)-infected woodchucks. Employing these animal models and the HBV replicating HepAD38 cells we examined the effect of Suz12/Znf198 down-regulation on gene expression. Genes analyzed include hepatic cancer stem cell markers

BAMBI, DKK1,2, DLK1, EpCAM, MYC,

and proliferation genes

CCNA1, CCND2, IGFII, MCM4-6, PLK1, RPA2

, and

TYMS

. Suz12 occupancy at the promoters of

BAMBI, CCND2, DKK2, DLK1, EpCAM

, and

IGFII

was demonstrated by chromatin immunoprecipitation in untransformed hepatocytes, but was markedly reduced in pX-transformed and Suz12 knockdown cells. Accordingly, we refer to these genes as “Suz12 repressed” genes in untransformed hepatocytes. The Suz12 repressed genes and proliferation genes were induced in HBV-replicating HepAD38 cells and, interestingly, they exhibited distinct expression profiles during hepatocellular carcinoma (HCC) progression in X/c-myc bitransgenics. Specifically,

CCND2, EpCAM

, and

IGFII

expression was elevated at the proliferative and preneoplastic stages in X/c-myc bitransgenic livers, whereas

BAMBI

and

PLK1

were overexpressed in hepatic tumors from X/c-myc bitransgenics and WHV-infected woodchucks. Importantly, most of these genes were selectively up-regulated in HBV-induced HCCs.

Conclusion

: The distinct expression profile of the identified Suz12 repressed genes in combination with the proliferation genes hold promise as biomarkers for progression of chronic HBV infection to HCC. (Hepatology 2012)
Primary biliary cirrhosis and cancer risk: A systematic review and meta-analysis
Authors: Liang Yan , Yang Zaixing , Zhong Renqian
Published: April 2012

Several studies have indicated that primary biliary cirrhosis (PBC) may be associated with increased risk of some cancers, but the results are controversial. We conducted a systematic review of studies to examine the association of PBC with cancer risk by meta-analysis. We searched the PubMed and EMBASE databases for English-language studies published before November 2011. Studies were included if they reported relative risk estimates with 95% confidence intervals (CIs) or related data for the association between PBC and cancer risk. Approximately 16,300 PBC patients from several countries were included in this analysis. Of the 3510 titles identified, 16 publications involving 17 studies meeting the inclusion criteria were included in the meta-analysis. Compared with the general population, PBC patients had a significantly higher risk of overall cancer (pooled rate ratio [RR], 1.55; 95% CI, 1.28-1.83) and hepatocellular carcinoma (HCC) (pooled RR, 18.80; 95% CI, 10.81-26.79). For stomach and pancreas cancers, the results of one study that only examined male patients with PBC indicated that PBC patients had increased risk of stomach cancer and pancreatic cancer, whereas the results of other studies of mixed-sex patients showed no significant association. Therefore, despite inconsistent results, the meta-analysis could not be conducted for assessing the association. PBC was not significantly associated with increased risk of other cancers.

Conclusion

: The present systematic review and meta-analysis demonstrate that PBC is closely associated with a greater risk of overall cancer and HCC, but not with other cancers. The data regarding the association between PBC and risks of several cancers need to be further confirmed in future studies. (Hepatology 2012)
Family Treatment for Bipolar Disorder and Substance Abuse in Late Adolescence
Authors: Miklowitz David J.
Published: April 2012

The initial onset of bipolar disorder occurs in childhood or adolescence in about 50% of patients. Early‐onset forms of the disorder have a poorer prognosis than adult‐onset forms and are frequently characterized by comorbid substance abuse. Clinical trials research suggests that family psychoeducational approaches are effective adjuncts to medication in stabilizing the symptoms of bipolar disorder in adults and youth, although their efficacy in patients with comorbid substance use disorders has not been systematically investigated. This article describes the family‐focused treatment (FFT) of a late adolescent with bipolar disorder and polysubstance dependence. The treatment of this patient and family required adapting FFT to consider the family's structure, dysfunctional alliance patterns, and unresolved conflicts from early in the family's history. The case illustrates the importance of conducting manual‐based behavioral family treatments with a psychotherapeutic attitude, including addressing unstated emotional conflicts and resistances that may impede progress.
Establishment and characterization of a novel chordoma cell line: CH22
Authors: Liu Xianzhe , Nielsen Gunnlager Petur , Rosenberg Andrew E. , Waterman Peter R. , Yang Wen , Choy Edwin , Sassi Slim , Yang Shuhua , Harmon David C. , Yang Cao , Schwab Joseph H. , Kobayashi Eisuke , Mankin Henry J. , Xavier Ramnik , Weissleder Ralph , Duan Zhenfeng , Hornicek Francis J.
Published: April 2012

Chordoma is a rare primary malignant bone tumor and there exist only a few established human chordoma cell lines. The scarcity of robust chordoma cell lines has limited the ability to study this tumor. In this report, we describe the establishment of a novel chordoma cell line and characterize its in vitro and in vivo behaviors. The tumor tissue was isolated from a patient with recurrent chordoma of the sacrum. After 6 months in culture, the chordoma cell line, referred here as CH22, was established. Microscopic analysis of two‐dimensional culture confirmed that the CH22 cells exhibited a typical vacuolated cytoplasm similar to the well‐established chordoma cell line U‐CH1. Electron microscopy showed cohesive cells with numerous surface filopodia, pockets of glycogen and aggregates of intermediate tonofilaments in cytoplasm. Three‐dimensional culture revealed that the CH22 cells could grow and form clusters by day 8. The MTT assays demonstrated that, compared with sensitive osteosarcoma cell lines, CH22 cells were relatively resistant to conventional chemotherapeutic drugs. Western blotting and immunofluorescence analysis confirmed that the CH22 cells expressed brachyury, vimentin, and cytokeratin. Finally, histological analysis of CH22 xenograft tumor tissues demonstrated the appearance of physaliphorous cells and positive staining of brachyury, cytokeratin, and S100. By CT and MRI, imaging xenografts showed the typical appearances seen in human chordomas. These findings suggest that the established novel human chordoma cell line CH22 and its tumorigenecity in SCID nude mice may serve as an important model for studying chordoma cell biology and the development of new therapeutic modalities. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:1666–1673, 2012
The importance of grouping of lymph node stations and rationale of three‐field lymphoadenectomy for thoracic esophageal cancer
Authors: Udagawa Harushi , Ueno Masaki , Shinohara Hisashi , Haruta Shusuke , Kaida Sachiko , Nakagawa Masatoshi , Tsurumaru Masahiko
Published: April 2012

Background and Objectives

Although the three‐field lymphadenectomy has established as a standard operation for esophageal cancer in Japan, criticism remains due to the lack of randomized controlled trials with a high EBM level. This retrospective study aims to clarify the effectiveness of the three‐field lymphadenectomy using the data obtained from 906 consecutive patients with esophageal cancer who underwent R0 esophagectomy with the three‐field lymphadenectomy.

Method

Efficacy Index (EI) was calculated for each lymph node station and grossly cervical, mediastinal, or abdominal dissection field. The values of EI were compared according to main tumor location.

Results

Cervical lymph node dissection had high EI in upper and middle thoracic esophageal cancer but it was very small in lower esophageal cancer. Abdominal lymphadenectomy for upper thoracic esophageal cancer had some but limited efficacy only in paracardiac and lesser curvature stations. Cervical lymphadenectomy for lower esophageal cancer showed some but limited efficacy only in cervical paraesophageal stations.

Conclusion

Our investigation clearly shows the effectiveness and importance of wide range lymph node dissection defined as D3 according to the Japanese N‐grouping system for thoracic esophageal cancer. The three‐field lymphadenectomy is regarded as a standard procedure for upper and middle thoracic esophageal cancer. J. Surg. Oncol. 2012; 106:742–747. © 2012 Wiley Periodicals, Inc.
The uniqueness and existence of solutions for the 3D Helmholtz equation in a step‐index waveguide with unbounded perturbation
Authors: Liu Lihan , Qin Yuehai , Xu Yongzhi , Zhao Yuqiu
Published: April 2012

In this paper, we study the 3D Helmholtz equation in a step‐index waveguide with unbounded perturbation, allowing the presence of guided waves. Our assumptions on the perturbed and source terms are too few. On the basis of the Green's function for the 3D homogeneous Helmholtz equation in a step‐index waveguide without perturbation, we introduce a generalized (out‐going) Sommerfeld–Rellich radiation condition, and then we prove the uniqueness and existence of solutions for the studied 3D Helmholtz equation satisfying our radiation condition. Copyright © 2012 John Wiley & Sons, Ltd.
Combined nuclear magnetic resonance spectroscopy and molecular dynamics study of growth hormone releasing hexapeptide GHRP‐6 and a cyclic analogue
Authors: Fernández‐Oliva Miguel , Santana Héctor , Suardíaz Reynier , Gavín José A. , Pérez Carlos S.
Published: April 2012

The Growth Hormone Releasing Hexapeptide, GHRP‐6 was the first of a family of synthetic peptides that enhance the release of the Growth Hormone by the pituitary gland in a dose‐dependent manner. Since its discovery, it has been used as a benchmark and starting point in numerous researches aiming to obtain new drugs. Complete resonance assignment of GHRP‐6 NMR spectra in both open and cyclic forms are reported, showing some differences to random coil chemical shifts. Connectivities observed in the ROESY spectra indicate spatial proximity between the aromatic residues side‐chains in both molecules, as well as between residues DPhe5 and Lys6 sidechains. An ensemble of 10 structures was generated for each one of the molecules, showing RMSD values indicative of nonrandom structures. Molecular Dynamics simulations, both with and without explicit solvent, were carried out for GHRP‐6 and its cyclic analogue. Conformational analysis performed on the trajectories showed a nonrandom structure with a well preserved backbone. The presence of geometrical patterns resembling those typical of π‐π interactions in both peptides, suggest that this kind of interactions may be relevant for the biological activity of GHRP‐6. Same conclusion can be drawn from the spatial proximity of residues DPhe5 and Lys6 sidechains. Copyright © 2012 John Wiley & Sons, Ltd.
Prenatal management and thoracoamniotic shunting in primary fetal pleural effusions: a single centre experience
Authors: Pellegrinelli J. M. , Kohler A. , Kohler M. , Weingertner A. S. , Favre R.
Published: April 2012

Objective

Primary fetal pleural effusions are rare. If severe, thoracoamniotic shunting is needed. Our objective was to study the management and outcomes of pleural effusions in our unit.

Methods

Retrospective analysis of primary fetal hydrothorax between 1991 and 2010.

Results

Of 41 cases, 23 (56%) were hydropic, and 27 (66%) required shunting.

Overall, 2 (4.8%) were diagnosed with a chromosomal condition and 4 (9.6%) with a congenital condition (3 Noonan syndrome, 1 mild structural cardiac defect). There were 5 terminations of pregnancy (TOP), 3 in utero deaths and 33 liveborn neonates (80%). Intact survival rate was 44% (12/27) among those shunted, 56% (23/41) among all cases and 70% (23/33) among all liveborn neonates.

Most (87.5%) neonatal deaths occurred in newborns delivered before 34 weeks of gestation. The survival rate was higher in nonhydropic compared with hydropic fetuses (85% vs 47%). There were no procedure‐related fetal losses. One in utero death was complicated by fatal maternal amniotic embolism.

Conclusion

Fetuses with pleural effusions should undergo expert prenatal workup. Hydropic fetuses and those with massive effusions are candidates for thoracoamniotic shunting. © 2012 John Wiley & Sons, Ltd.
Sex, Education and Procrastination: An Epidemiological Study of Procrastinators’ Characteristics from A Global Sample
Authors: Steel Piers , Ferrari Joseph
Published: April 2012

Procrastination is a common form of self–regulatory failure with substantive connections to lower levels of health, wealth and well–being. Conducting an epidemiological study, we determined the characteristics of prototypical procrastinators from a global sample based on several relevant self–reported demographic variables. Using an internet sampling strategy, we surveyed 16 413 English–speaking adults (58.3% women; 41.7% men: M age = 38.3 years, SD = 14), specifically on the variables of sex, age, marital status, family size, education, community location, and national origin. Almost all the results were statistically significant because of our large sample size. However, procrastination tendencies were most prominently associated with sex, age, marital status, education and nationality. Procrastinators tended to be young, single men with less education, residing in countries with lower levels of self–discipline. Notably, procrastination mediated the relationship between sex and education, providing further support that men are lagging behind women academically because of lower self–regulatory skills. Given procrastination's connection with a variety of societal ailments (e.g. excessive debt, delayed medical treatment), identifying risk factors and at risk populations should be helpful for directing preventative public policy. Copyright © 2012 John Wiley & Sons, Ltd.
The Use of Non‐Equilibrium Plasmas for the Synthesis of Heterogeneous Catalysts
Authors: Witvrouwen Toon , Paulussen Sabine , Sels Bert
Published: April 2012

A review of published works in the field of catalyst synthesis and treatment with the use of non‐equilibrium plasma techniques has been composed. Non‐equilibrium plasmas, also called low temperature plasmas, are known for their high reactivity (high electron temperature), while keeping the overall gas temperature low. Non‐equilibrium plasmas are often applied for dry surface modifications as an environment friendly alternative for solvent‐based techniques. In the field of heterogeneous catalysis, non‐equilibrium plasmas are most commonly used for the treatment of catalytically active surfaces. Such applications can result into highly dispersed catalysts with high activity and stability, such as photo‐catalytically active titanium dioxide films. Moreover, (non‐equilibrium) plasma‐assisted chemical vapor deposition can also be used for the synthesis of powder‐like materials used in heterogeneous catalysis for a wide range of applications, for example, ultrafine Fe2O3. The research field is still emerging, but already proves to be very promising, as will be shown in the review.

magnified image
Alveolar concentration and bronchial flux of nitric oxide: Two linear modeling methods evaluated in children and adolescents with allergic rhinitis and atopic asthma
Authors: Chládková Jirina , Senkerík Marian , Havlínová Zuzana , Krcmová Irena , Chládek Jaroslav
Published: April 2012

Objective

Alveolar concentration (CANO) and bronchial flux (JawNO) of nitric oxide (NO) characterize the contributions of peripheral and proximal airways to exhaled NO. Both parameters can be estimated using a two‐compartment model if the fraction of NO in orally exhaled air (FENO) is measured at multiple constant expiratory flow rates (V). The aim of this study was to evaluate how departures from linearity influence the estimates of CANO and JawNO obtained with the help of linear regression analysis of the relationships between FENO and 1/V (method P), and between the NO output (VNO = FENO × V) and V (method T). Furthermore, differences between patients with atopic asthma (AA) and allergic rhinitis (AR) and between methods P and T were assessed.

Design

Measurements of FENO were performed with a chemiluminiscence analyzer at five levels of V ranging from 50 to 250 ml/sec in school children and adolescents with mild to moderate‐severe AA treated by inhaled corticosteroids (N = 42) and AR (N = 20).

Results

Violation of the linearity condition at V ≤ 100 ml/sec caused shifts between methods with regard to the partition of exhaled NO into alveolar (CANO: P > T) and bronchial (JawNO: T > P) components. Both methods gave similar results in the linear range of 150–250 ml/sec: The mean ratios P/T and limits of agreement calculated in AA and AR patients were 1.03 (0.49–1.56) and 1.07 (0.55–1.59) for CANO and 1.03 (0.73–1.33) and 0.99 (0.90–1.10) for JawNO, respectively. No significant differences between AA and AR were found in CANO and JawNO calculated in the linear range by the T method {medians (inter‐quartile ranges): 1.7 ppb (0.9–3.9) vs. 2.3 ppb (0.8–3.7), P = 0.91; 1,800 pl/sec (950–3,560) vs. 1,180 pl/sec (639–1,950), P = 0.061}. However, the flow‐dependency of the estimates was markedly higher in AA than in AR patients: CANO was decreased 2.8‐fold vs. 1.5‐fold and JawNO was increased 1.5‐fold vs. 1.2‐fold in the linear range as compared to the range of 50–250 ml/sec. In both groups, the median standard errors (SE) of the JawNO estimates were similar for the metods P and T and small (<15%) regardless of the range for expiratory flows. The precision of CANO estimates was less in all ranges. For both methods, the SE of the estimates obtained in the range of 150–250 ml/sec exceeded 50% in asthmatics and 30% in AR patients, respectively.

The results show that FENO has to be measured at several expiratory flows ≥100 ml/sec for the accurate estimation of CANO and JawNO using linear methods P and T in children and adolescents with AA and AR. A stepwise procedure for detecting nonlinearity and evaluating the quality of FENO measurements is suggested. Pediatr Pulmonol. 2012. 47:1070–1079. © 2012 Wiley Periodicals, Inc.
Non invasive positive pressure ventilation in infants with respiratory failure
Authors: Cavari Yuval , Sofer Shaul , Rozovski Uri , Lazar Isaac
Published: April 2012

Objective

To determine whether non‐invasive positive pressure ventilation (NIPPV) delivered via nasal prongs can alleviate the need for tracheal intubation and invasive ventilation in infants admitted to the pediatric intensive care unit (PICU) with impending respiratory failure, and to find predictive factors for success or failure with this mode.

Design

A single center retrospective cohort study.

Setting

PICU in a university affiliated hospital.

Patients

During the 14 months of the study period we recovered 22 NIPPV episodes in 19 infants (median age 65 days) with impending respiratory failure. The patient's respiratory failure etiologies were bronchiolitis (n = 13), pertussis (n = 3), and other respiratory conditions (n = 6).

Measurements and Results

In 64% of the cases, intubation was prevented and the patients were weaned off to spontaneous breathing (Responders group). 36% failed NIPPV and had to be intubated and invasively ventilated (Non‐responders group). Apneic episodes were the indication for ventilation in 11 patients (50%) with a 73% success rate in preventing invasive ventilation. Hypoxemic respiratory failure was present in nine patients (41%) and the rate of success was 44%. Two patients with post extubation respiratory distress, improved with NIPPV. Responders and non‐responders did not differ with regard to demographics or disease severity prior to initiation of NIPPV. After initiating NIPPV respiratory rate and the need for sedation were lower in the NIPPV responders.

Conclusions

In a set group of patient population such as infants with apnea secondary to bronchiolitis NIPPV may be successful to reduce the need for invasive ventilation. Our study failed to detect any physiological or clinical markers which could distinguish between so called “responders” and “non‐responders” before initiating NIPPV. Pediatr Pulmonol. 2012. 47:1019–1025. © 2012 Wiley Periodicals, Inc.
Kinetics of thermally induced heat shock protein 27 and 70 expression by bone marrow‐derived mesenchymal stem cells
Authors: Moloney Teresa C. , Hoban Deirdre B. , Barry Frank P. , Howard Linda , Dowd Eilís
Published: April 2012

Although bone marrow‐derived mesenchymal stem cells (MSCs) are an attractive cell therapy candidate, their potential is limited by poor survival following transplantation. Over‐expression of anti‐apoptotic heat shock proteins using viral vectors can improve the survival of these cells under stressful conditions in vitro and in vivo. It is also possible to induce heat shock protein expression in many cell types by simply exposing them to a transient, nonlethal elevation in temperature. The response profile of MSCs to such a thermal stress has not yet been reported. Therefore, this study sought to determine the kinetics of thermally induced heat shock protein expression by MSCs in vitro. To determine if heat shock protein expression was a function of thermal stress exposure time, MSCs were exposed to 42°C for 15, 30, 45, and 60 min and were harvested 24 h later. To establish the time‐course of heat shock protein expression, MSCs were heat shocked for 60 min and harvested 2, 24, 48, 72, 96, and 120 h later. The cells were then analyzed for Hsp27 and Hsp70 expression by Western blot. Densitometric analysis revealed that exposure to a thermal stress induced expression of both Hsp27 and Hsp70 and that the level of expression was dependant on stress exposure time. Following 60 min of heat stress, both Hsp27 and Hsp70 accumulated maximal expression after 48 h with both proteins returning to constitutive expression levels by 120 h. This study demonstrates that heat shock protein expression can be induced in MSCs by a simple thermal stress.
Assessing the reconstruction of macromolecular assemblies with toleranced models
Authors: Dreyfus Tom , Doye Valérie , Cazals Frédéric
Published: April 2012

We introduce toleranced models (TOMs), a generic and versatile framework meant to handle models of macromolecular assemblies featuring uncertainties on the shapes and the positions of proteins. A TOM being a continuum of nested shapes, the inner (resp. outer) ones representing high (low) confidence regions, we present topological and geometric statistics assessing features of this continuum at multiple scales. While the topological statistics qualify contacts between instances of protein types and complexes involving prescribed protein types, the geometric statistics scale the geometric accuracy of these complexes. We validate the TOM framework on recent average models of the entire nuclear pore complex (NPC) obtained from reconstruction by data integration, and confront our quantitative analysis against experimental findings related to complexes of the NPC, namely the Y‐complex, the T‐complex, and the Nsp1–Nup82–Nup159 complex. In the three cases, our analysis bridges the gap between global qualitative models of the entire NPC, and atomic resolution models or putative models of the aforementioned complexes. In a broader perspective, the quantitative assessments provided by the TOM framework should prove instrumental to implement a virtuous loop “model reconstruction–model selection”, in the context of reconstruction by data integration. Proteins 2012; © 2012 Wiley Periodicals, Inc.
The reductive reaction mechanism of tobacco nitrite reductase derived from a combination of crystal structures and ultraviolet–visible microspectroscopy
Authors: Nakano Shogo , Takahashi Misa , Sakamoto Atsushi , Morikawa Hiromichi , Katayanagi Katsuo
Published: April 2012

Assimilatory nitrite reductase (aNiR) reduces nitrite to an ammonium ion and has siroheme and a [Fe4S4] cluster as prosthetic groups. A reaction mechanism for Nii3, an aNiR from tobacco, is proposed based on high resolution X‐ray structures and UV–Vis (ultraviolet–visible) microspectroscopy of Nii3‐ligand complexes. Analysis of UV–Vis spectral changes in Nii3 crystals with increasing X‐ray exposure showed prosthetic group reductions. In Nii3‐NO structures, X‐ray irradiation enhanced the progress of the reduction reaction, and cleavage of the NO bond was observed when X‐ray doses were increased. Crystal structures of Nii3 with other bound ligands, such as Nii3‐NO and Nii3‐NH2OH, were also determined. Further, by combining information from these Nii3 ligand‐bound structures, including that of Nii3‐NO, with UV–Vis microspectral data obtained using different X‐ray doses, a reaction mechanism for aNiR was suggested. Cleavage of the two NO bonds of nitrite was envisaged as a two‐step process: first, the NO bond close to Lys224 was cleaved, followed by cleavage of the NO bond close to Arg109. X‐ray structures also indicated that aNiR‐catalyzed nitrite reduction proceeded without the need for conformation changes in active site residues. Geometrical changes in the ligand molecules and the placement of neighboring water molecules appeared to be important to the stability of the active site residue interactions (Arg109, Arg179, and Lys224) and the ligand molecule. These interactions may contribute to the efficiency of aNiR reduction reactions. Proteins 2012; © 2012 Wiley Periodicals, Inc.
Cr induced nanocrystallization of a ‐Si thin films: its mechanism
Authors: Ahamad Mohiddon Md. , Lakshun Naidu K. , Dalba G. , Rocca F. , Ghanashyam Krishna M.
Published: April 2012

The mechanism involved in the metal induced a ‐Si crystallization has been investigated by X‐ray absorption spectroscopy for Cr. The growth process involves the deposition on fused silica (FS) of FS/Cr(200nm)/a ‐Si(400nm) stacks (FCS) and FS/a ‐Si(400nm)/Cr(200nm) stacks (FSC) at different substrate temperatures by electron beam evaporation technique. X‐ray absorption spectra were measured at different incidence angles (total reflection, 10° and 45°) to understand the evolution of the local structure of Cr components diffusing from bottom to top or from top to bottom in FCS and FSC stacks respectively. From the qualitative and quantitative analysis, we may conclude that, in case of Cr induced MIC, at first Cr diffuses into the a ‐Si matrix, then it partially reacts with a ‐Si to form CrSi2. This will later act as crystallizing seed for a ‐Si crystallization (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Nano‐droplet formation in polymer dispersed liquid crystals
Authors: Torres‐Cisneros M. , LiKamWa Patrick , May‐Arrioja D. , Ibarra‐Manzano O. G. , Plascencia‐Mora H. , Aguilera‐Gómez E. , Aviña‐Cervantes J. G. , Sanchez‐Mondragon J. J. , Song Q. , Andrade‐Lucio J. A. , Guzmán‐Cabrera R.
Published: April 2012

In this work we analyse the fabrication of Polymer Dispersed Liquid Crystals (PDLCs) using SU8‐2002‐2007 photoresist and 5CB and E7 Liquid Crystals. Also we report the nonlinear optical behaviour for these materials and for Polymer Dispersed Liquid Crystals with a Twisted Cell (T‐PDLC). We found that depending of several parameters, the droplets size varies from nano to micro dimensions. We report for first time, to our best knowledge, the synthesis of a SU8 Polymer Dispersed Liquid Crystal (PDLC) by using the polymer SU8 photoresist and liquid crystals (LC) and also the nonlinear behaviour of T‐PDLC. We have characterized the droplets formation from nano to micron size depending of the different variables in the synthesis. We have used this PDLC in microfabrication as planar waveguides of different thickness over Si wafers. Our results also show that PDLCs present low NL optical Kerr coefficient (n2 about 10‐9cm2/W) and that it is three orders of magnitude larger in T‐PDLC. Nevertheless, the fabrication processes of T‐PDLCs make impossible their use in microfabrication. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of oxygen on light emission from amorphous silicon nanoclusters
Authors: Yeltsina Olga S. , Andronikov Dmitrii A. , Kukin Alexei V. , Vainshtein Julia S. , Sreseli Olga M.
Published: April 2012

Surface effects, in particular oxygen passivation, are known to have drastic influence on emission spectra of semiconductor nanoclusters. The goal of this work was to obtain light emission from amorphous silicon nanoclusters by means of oxygen passivation. Granulated films of amorphous silicon nanoclusters were fabricated by the laser electrodispersion technique, which allows obtaining nanoclusters of uniform sizes. Two methods were applied in order to incorporate oxygen into the films, and both result in improvement of the luminescent properties of the films. The role of oxygen passivation as well as the effect of thermal annealing is considered. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ab‐initio study of silicon nanowires
Authors: Karazhanov Smagul , Marstein Erik , Holt Arve
Published: April 2012

Four different size nanowires of Si have been studied by the density functional theory. We have shown that distinct from the bulk silicon with indirect band structure the one of the silicon nanowires is direct. Both valence band maximum and conduction band minimum are located at the Γ point. Optical properties of the nanowires have been studied. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Separation of energies of the direct (through‐space) and indirect (through‐bridge) interactions in SCF LCAO MO theory*
Authors: Nalewajski Roman F.
Published: April 2012

Within the standard SCF LCAO MO theory the electronic energy is partitioned into components associated with pairs of atomic orbitals and contributions due to the direct (through‐space) and indirect (through‐bridge) chemical bonds in molecules are identified. Conditions for the overall bonding effect of the implicit bridge interactions are qualitatively examined using the simplest case of the three‐orbital model and possible extensions including electron correlation are briefly commented upon. © 2012 Wiley Periodicals, Inc.
Divide‐and‐conquer‐based symmetry adapted cluster method: Synergistic effect of subsystem fragmentation and configuration selection
Authors: Yoshikawa Takeshi , Kobayashi Masato , Nakai Hiromi
Published: April 2012

In this article, we develop the symmetry adopted cluster (SAC) theory based on the divide‐and‐conquer (DC) method, which accomplishes the linear‐scaling computational time with respect to the system size, as well as the DC‐based coupled cluster (CC) method does. Although the perturbative configuration selection adopted in the SAC program significantly reduces its computational cost compared with the CC calculations, the reduction of the configurations leads to less inclusion of the total correlation energy. However, the numerical assessments confirmed that the use of the local orbitals constructed in each subsystem in DC‐SAC calculations reduces the loss in total correlation energy, which provides more reliable total and relative energies than the standard SAC method. © 2012 Wiley Periodicals, Inc.
The role of aromaticity on the building of nanohybrid materials functionalized with metalated (Au(III), Ag(III), Cu(III)) extended porphyrins and single‐walled carbon nanohorns: A theoretical study
Authors: Muñiz Jesús , Sansores Enrique , Olea Alfredo , Valenzuela Edgar
Published: April 2012

An ab initio, systematic study on the aromaticity involving the group of metalated extended porphyrins, termed meso‐hexakis(pentafluorophenyl)‐substituted[26]hexaphyrin(1.1.1.1.1.1) (HP), was performed for the first time. The aromatic behavior of the system shifted to antiaromatic in the [28]HP analogue, due to the presence of hydrogen atoms that break the orbital symmetry. The absorption bands observed in the experiment were assigned to an intraligand charge transfer, where the intrametallic character is also important. The excited states reveal the absorption of visible light and the possibility of electronic transfer to different systems. We propose a system such as single‐walled carbon nanohorns (SWCNHs), due to their special electronic properties, and predict a novel nanohybrid material. The evidence of electronic communication between both species is presented in this work. The HP aromaticity and the spatial configuration of the interaction with SWCNHs are also related to the strength of electronic transfer among the systems, making the HP metalated antiaromatic species and their corresponding nanohybrids potential candidates to be used as building blocks in photovoltaic cell materials. © 2012 Wiley Periodicals, Inc.