bluuebunny/crossref_metadata_2025 huggingface dataset:
Multispacecraft observations of fundamental poloidal waves without ground magnetic signatures
Authors: Takahashi Kazue , Hartinger Michael D. , Angelopoulos Vassilis , Glassmeier Karl‐Heinz , Singer Howard J.
Published: June 2013

Poloidal standing Alfvén waves observed by spacecraft usually have a second harmonic standing wave structure. On very rare occasions, fundamental poloidal waves have been observed in association with giant pulsations observed on the ground. In this paper, we report multisatellite observations of fundamental poloidal waves that did not produce any clearly associated magnetic pulsations on the ground. The waves were observed on 10 November 2008, at ~1830 Universal Time (UT) at THEMIS‐A and THEMIS‐D and at ~2010 UT at THEMIS‐E as these spacecraft passed L ~ 11 and magnetic local time (MLT) ~ 0900. The GOES‐11 geostationary satellite (L ~ 7) also observed poloidal waves at ~1730 UT when it was at ~0900 MLT. The poloidal waves at THEMIS were characterized by narrow‐band oscillations (frequency ~4 mHz) of the ion bulk velocity and magnetic field in the radial direction. We identify the waves at THEMIS to be the fundamental mode on the basis of the wave properties observed slightly south of the magnetic equator: large velocity amplitude, small magnetic field amplitude, and ~90° phase delay of the magnetic field relative to the velocity. The azimuthal wave number is found to be ~70 (if we assume westward propagation) or ~200 (if we assume eastward propagation) from the phase delay between THEMIS‐A and THEMIS‐D. This wave number explains why there were no corresponding magnetic field oscillations on the ground. These observations imply that only a subset of fundamental poloidal waves excited in the magnetosphere is observed on the ground as giant pulsations.
Quasiperiodic emissions observed by the Cluster spacecraft and their association with ULF magnetic pulsations
Authors: Němec F. , Santolík O. , Pickett J. S. , Parrot M. , Cornilleau‐Wehrlin N.
Published: June 2013

Quasiperiodic (QP) emissions are electromagnetic waves at frequencies of about 0.5–4 kHz characterized by a periodic time modulation of the wave intensity, with a typical modulation period on the order of minutes. We present results of a survey of QP emissions observed by the Wide‐Band Data (WBD) instruments on board the Cluster spacecraft. All WBD data measured in the appropriate frequency range during the first 10 years of operation (2001–2010) at radial distances lower than 10 RE were visually inspected for the presence of QP emissions, resulting in 21 positively identified events. These are systematically analyzed, and their frequency ranges and modulation periods are determined. Moreover, a detailed wave analysis has been done for the events that were strong enough to be seen in low‐resolution Spatio‐Temporal Analysis of Field Fluctuations‐Spectrum Analyzer data. Wave vectors are found to be nearly field‐aligned in the equatorial region, but they become oblique at larger geomagnetic latitudes. This is consistent with a hypothesis of unducted propagation. ULF magnetic field pulsations were detected at the same time as QP emissions in 4 out of the 21 events. They were polarized in the plane perpendicular to the ambient magnetic field, and their frequencies roughly corresponded to the modulation period of the QP events.
Significant loss of energetic electrons at the heart of the outer radiation belt during weak magnetic storms
Authors: Hwang J. , Lee D.‐Y. , Kim K.‐C. , Shin D.‐K. , Kim J.‐H. , Cho J.‐H. , Park M.‐Y. , Turner D. L.
Published: June 2013

For various reasons, the Earth's outer radiation belt often exhibits dramatic and sudden increases or decreases in the observed particle flux. In this paper, we report three dropout events of energetic electrons observed by multiple spacecraft while traveling across the outer radiation belt. The three events were first identified based on observations of a significant dropout in the >2 MeV electron flux at geosynchronous orbit. Subsequently, for each event, we analyzed the energetic electron data obtained near the magnetic equator by THEMIS spacecraft to determine the responses of the entire outer radiation belt. Our analysis is mainly based on the electron fluxes measured at energies of 52 keV, 203 keV, and 719 keV, and on the phase space densities estimated for the first adiabatic invariant μ values of 100 MeV/G, 200 MeV/G, and 300 MeV/G. The main shared feature among the three events is that while, for the lowest energy, sources from the convection and/or particle injections of plasma sheet electrons dominate over losses, the higher energies exhibit a dramatic dropout effect that penetrates deeply into L ~ 4.5 – 5. In terms of the phase space density, a similar dropout effect is clearly seen for the μ values of 200 MeV/G and 300 MeV/G, while the convection effect and/or injections dominates for μ = 100 MeV/G. What is astonishing about this dropout phenomenon is that the three events are all associated with only very weak magnetic storms with a SYM‐H minimum of ‐40 nT or larger. This implies that a significant loss of electrons deep inside the outer radiation belt can occur even during a very weak magnetic storm. Low‐altitude observations of electrons by NOAA POES satellites indicate no significant atmospheric precipitation due to strong diffusion. Our simulations with various conditions suggest that radial diffusion effect in combination with the magnetopause shadowing are responsible for the observed dropouts to a large extent for all of the three events, although the contribution by the weak atmospheric precipitation that might have been missed by the NOAA POES observations can be non‐negligible.
RETHINKING ACP‐EU RELATIONS AFTER COTONOU: TENSIONS, CONTRADICTIONS, PROSPECTS
Authors: Carbone Maurizio
Published: June 2013

This Policy Arena has two main objectives. First, it seeks to unravel how the partnership between the European Union (EU) and the African, Caribbean and Pacific (ACP) Group has evolved since the adoption of the Cotonou Agreement in 2000, including its 2005 and 2010 reviews and the implementation of its three key pillars (development cooperation, trade and political dialogue). Second, it explores the prospects of EU‐ACP relations in the medium to long term. In particular, it discusses whether the ACP‐EU cooperation framework is still relevant in the light of a number of global changes and, more specifically, whether the ACP configuration is still useful to its members. To address these issues, both the EU and the ACP Group have established two working groups. Within the ACP, voices are critical of the EU‐ACP partnership, but there appears to be more willingness to reform and renew it. Within the EU, the record of the Cotonou Agreement is seen more positively, but there seems to be less willingness to preserve it. The third review of the Cotonou Agreement to be finalised by 2015, and more generally its expiration in 2020, provides an opportunity – to which this Policy Arena seeks to contribute – to rethink the EU‐ACP cooperation model. Copyright © 2013 John Wiley & Sons, Ltd.
Differential expression of ISG20 in chronic hepatitis B patients and relation to interferon‐alpha therapy response
Authors: Lu Xi , Qin Bo , Ma Qian , Yang Chun , Gong Xue‐Yan , Chen Li‐Min
Published: June 2013

The 20 kDa exonuclease encoded by the interferon‐stimulated gene, ISG20, can inhibit the replication of hepatitis B virus (HBV), and may represent a clinically useful prognostic marker for response to interferon‐alpha (IFN‐α) antiviral therapy. The present study was designed to investigate the differential expression patterns of ISG20 in liver biopsy samples from treatment‐naive patients with chronic hepatitis B and non‐HBV infected controls and to determine the relation between the differential expression and IFN‐α treatment outcome (responders vs. non‐responders). HBV infection status was determined by measuring levels of hepatitis B surface antigen (HBsAg) by chemoluminescence immunoassay and of HBV DNA by real‐time quantitative (q)PCR. ISG20 protein and mRNA expressions were assessed by immunohistochemistry and qPCR, respectively. Chronic hepatitis B responders showed significantly higher levels of ISG20 protein and mRNA expressions than either the chronic hepatitis B non‐responders or the controls. Moreover, increased expression of ISG20 in both the nucleus and cytoplasm was correlated with positive response to IFN‐α treatment. Thus, active transcription and translation of ISG20 may represent a marker to identify chronic hepatitis B patients likely to respond to IFN‐α therapy. Prognostic clinical strategies based upon this marker may include genomic screening methods and immunohistochemical staining of liver biopsies. J. Med. Virol. 85:1506–1512, 2013. © 2013 Wiley Periodicals, Inc.
An efficient approximation for arbitrary port suppression of multiport scattering parameters
Authors: Zadehgol Ata
Published: June 2013

The multiport scattering (S‐) parameter matrix is increasingly utilized to compose models of large bit‐width interconnect systems with broadband characteristics (frequency range of zero to tens of gigahertz) to perform increasingly accurate signal‐integrity and power‐integrity simulations. The search for an optimal solution space often requires generation of S‐parameter models of interconnect systems for various signal/ground pin mappings, a process that can be computationally costly if the structure is electromagnetically solved for each distinct pin mapping. To expedite this model‐generation process, we propose a method in which an N‐port structure is electromagnetically solved only once to yield an N × N S‐matrix; then, a linear system is formulated and solved to yield an (N − M) × (N − M) post‐suppressed S‐matrix (where M is the number of suppressed ports). This approach results in significant computational savings through elimination of electromagnetic field‐solver runs for each distinct pin mapping. Included in this paper is a discussion about the limitations of this technique and several numerical examples. Copyright © 2013 John Wiley & Sons, Ltd.
Purification and characterization of a phospholipase by Photobacterium damselae subsp. piscicida from cobia Rachycentron canadum
Authors: Hsu Po‐Yuan , Lee Kuo‐Kau , Hu Chih‐Chuang , Liu Ping‐Chung
Published: June 2013

Toxicity of the extracellular products (ECPs) and the lethal attributes of phospholipase secreted by pathogenic Photobacterium damselae subsp. piscicida from cobia Rachycentron canadum was studied. An extracellular lethal toxin in the ECPs was partially purified by using Fast Protein Liquid Chromatography system. A protein band (27 kDa) exhibited phospholipase activity on Native‐PAGE (by 0.3% egg yolk agar‐overlay), was excised and eluted. The pI value of the purified phospholipase was determined as 3.65 and was determined as a phospholipase C by using the Amplex™ Red phosphatidylcholine ‐Specific phospholipase C Assay kit. The phospholipase showed maximum activity at temperature around 4–40 °C and maximal activity at pH between 8 and 9. The enzyme was inhibited by ethylenediamine‐tetraacetic acid (EDTA) and sodium dodecyl sulfate (SDS); but was activated by Ca2+ and Mg2+ and inactivated by Zn2+ and Cu2+. Both the ECPs and phospholipase were hemolytic against erythrocytes of cobia and lethal to the fish with LD50 values of 3.25 and 0.91 µg protein g−1 fish, respectively. In toxicity neutralization test, the rabbit antisera against the phospholipase could neutralize the toxicity of ECPs, indicating that the phospholipase is a major extracellular toxin produced by the bacterium.
Catabolic plasmid specifying polychlorinated biphenyl degradation in Cupriavidus sp. strain SK‐4: Mobilization and expression in a pseudomonad
Authors: Ilori Matthew O. , Picardal Flynn W. , Aramayo Rodolfo , Adebusoye Sunday A. , Obayori Olufemi S. , Benedik Michael J.
Published: June 2013

Strain SK‐4, a polychlorinated biphenyl (PCB) degrader previously reported to utilize di‐ortho‐substituted biphenyl, was genotypically re‐characterized as a species of Cupriavidus. The bacterium harbored a single plasmid (pSK4), which resisted curing and which, after genetic marking by a transposon (SK4Tn5), could be mobilized into a pseudomonad. Analysis of pSK4 in both the transconjugant and the wild type revealed that it specifies the genes coding for 2‐hydroxy‐2,4‐pentadienoate degradation in addition to those of the upper biphenyl pathway. Expression of the benzoate metabolic pathway in the transconjugant is evidence suggesting that the benzoate catabolic genes are also localized on the plasmid. This implies that pSK4 codes for all the genes involved in biphenyl mineralization. It is therefore reasonable to propose that the plasmid is the determinant for the unique metabolic capabilities known to exist in Cupriavidus sp. strain SK‐4.
Purification and characterization of a ribonuclease with antiproliferative activity from the mystical wild mushroom Tuber indicum
Authors: Xiao Chen , Feng ShanShan , Wang HeXiang , Gong ZhiYuan , Ng TziBun
Published: June 2013

An RNase with a molecular mass of 28 kDa and with high ribonucleolytic activity toward poly(A) was purified from the ascocarps of Tuber indicum. The purification procedure involved ion exchange chromatography on diethylaminoethyl cellulose, Q‐Sepharose and Mono Q, and gel filtration by fast protein liquid chromatography on Superdex 75. The pH and temperature optima of the RNase were 7.2 and 50 °C, respectively. The ranking of its activity toward various polyhomoribonucleotides was poly(A)>poly(C)>poly(G) ≈ poly(U). All of the metal ions used in this study, except for the K+ ions, curtailed the activity of the RNase. The RNase activity was reduced by ethylene diamine tetraacetic acid (EDTA), dithiothreitol (DTT), and sodium dodecyl sulfate (SDS) by 42.2%, 75.5%, and 96.6%, respectively. The RNase inhibited the proliferation of hepatoma (HepG2) and human breast cancer cell lines (MCF7), with half‐maximal inhibitory concentrations (IC50) of 12.6 and 16.6 μM, respectively.
Do Leaders of Small and Medium‐Sized Businesses Base Decisions on Intuition? An Empirical Investigation Among West African Managers
Authors: Bocco Bertrand Sogbossi , Merunka Dwight
Published: June 2013

Intuitive judgments are common among managers. They rely on intuition to facilitate their managerial decision making, and use it to synthesize information rapidly, economically, and effectively. Intuition contrasts sharply with highly rational decision‐making systems that represent the bases of management education and management practices. Unlike concepts that appear similar, such as instinct, guessing, or insight, intuitive decision making is nonconscious, holistic, quick, and affect‐driven, and also involves emotions. Qualitative interviews and an empirical investigation conducted with more than 300 managers and entrepreneurs at small and medium‐sized organizations in West Africa reveal that intuition is a key resource for managerial decision making. In fact, this effortless, automatic processing of information may be more efficient than the use of deliberate rational processes when making decisions. © 2013 Wiley Periodicals, Inc.
Exports and Market Commitment in Managerial SMEs: Do Pioneers Do It Better?
Authors: Moore Ernesto Tapia
Published: June 2013

How do the market commitment variables in the internationalization process model interact? Does that interaction affect how and why export managers implement their activities the way they do? Empirical research focusing on French managerial small and medium‐sized enterprises (SMEs) identified two groups of export leaders—“pioneers” and “managers”—and examined their beliefs concerning market commitment, risk, and uncertainty. The internationalization process model was then used to determine which type of export director performs most effectively. Results showed that the “pioneer's way,” although limited to smaller SMEs, was more proficient and could be extended to larger SMEs. © 2013 Wiley Periodicals, Inc.
Developing fruit‐based nutritious snack bars
Authors: da Silva Edson P , Siqueira Heloisa H , do Lago Rafael Carvalho , Rosell Cristina M , Vilas Boas Eduardo V de Barros
Published: June 2013

BACKGROUND

Marolo (Annona crassiflora Mart) is a typical savannah fruit that is very nutritious and highly appreciated. However, its consumption has been limited to fresh fruit. The objective of this study was to evaluate the potential use of marolo flour in the production of healthy snack bars to valorise this fruit and provide an alternative ready‐to‐eat nutritious product. Snack bars containing increasing amounts of marolo flour (5 g 100 g−1, 10 g 100 g−1, 15 g 100 g−1, 20 g 100 g−1, expressed in w/w) were produced and the physico‐chemical and sensory characteristics were determined.

RESULTS

Levels up to 20% marolo flour can be incorporated in snack bars with some minor changes in pH and moisture content but with an increase of 2.4‐fold in dietary fibre content and also 1.3‐fold of vitamin C, minerals and antioxidant activity. In addition, up to 10% marolo flour improves significantly the sensory properties of the snack bars, namely appearance, taste, texture and overall acceptance.

CONCLUSION

Marolo flour can be considered an alternative flour for obtaining healthy snack bars, with increased nutritional and sensory quality. © 2013 Society of Chemical Industry
Entecavir and hepatitis B immune globulin in patients undergoing liver transplantation for chronic hepatitis B
Authors: Perrillo Robert , Buti Maria , Durand Francois , Charlton Michael , Gadano Adrian , Cantisani Guido , Loong Che-Chuan , Brown Kimberly , Hu Wenhua , Lopez-Talavera Juan Carlos , Llamoso Cyril
Published: June 2013

For patients undergoing liver transplantation (LT) for hepatitis B virus (HBV)–related liver disease, the current standard of care for preventing reinfection of the allograft is nucleoside analogue therapy combined with hepatitis B immune globulin (HBIG). Entecavir has demonstrated high efficacy and a favorable safety profile for chronic hepatitis B (CHB) treatment, but data for patients undergoing HBV-related LT are limited. This study assessed the safety and efficacy of entecavir combined with various HBIG regimens after CHB-related LT. In this phase 3b, single-arm, open-label study, 65 patients undergoing LT for CHB-related liver disease with an HBV DNA load <172 IU/mL at LT received entecavir (1.0 mg daily) for 72 weeks after LT. The primary endpoint was the proportion of evaluable patients (treated for ≥4 weeks) with virological recurrence (HBV DNA level ≥50 IU/mL) through week 72. Concomitant HBIG therapy was received by 64 of the 65 enrolled patients, and 44% of these patients received high-dose HBIG (any HBIG dose in the specified interval ≥10,000 IU). Through week 72, all 61 patients evaluable for the efficacy analysis had undetectable HBV DNA. The Kaplan-Meier estimate of patients without hepatitis B surface antigen (HBsAg) recurrence at week 72 was 0.9655. Two patients experienced a reappearance of HBsAg, but both remained HBV DNA− until the last follow-up. The frequency and nature of adverse events were consistent with those expected for this patient population. Serum creatinine increments ≥0.3 mg/dL and ≥0.5 mg/dL occurred in 62% and 39% of the patients, respectively, and all of these patients received calcineurin inhibitor therapy. In conclusion, in this population of patients treated with entecavir after CHB-related LT, entecavir was well tolerated and effective in maintaining viral suppression, even in individuals who experienced a reappearance of HBsAg.
Living related liver transplantation for hepatitis B–related liver disease without hepatitis B immune globulin prophylaxis
Authors: Wadhawan Manav , Gupta Subash , Goyal Neerav , Taneja Sunil , Kumar Ajay
Published: June 2013

Hepatitis B immune globulin (HBIG) is routinely used in liver transplantation for hepatitis B virus (HBV)–related liver disease. With potent oral antivirals, HBIG may not be required. We conducted a prospective trial to evaluate living related liver transplantation (LRLT) without HBIG. Eighty-nine patients with HBV-related liver disease underwent LRLT between January 2005 and January 2012. All donors were vaccinated with the HBV vaccine. All patients were given oral antivirals for HBV before transplantation. Patients with HBV DNA levels ≤ 2000 IU/mL were not given HBIG, and patients with HBV DNA levels > 2000 IU/mL were given HBIG. Recurrence was defined as HBV DNA positivity 6 months after transplantation. Seventy-five of the 89 patients who underwent LRLT for HBV-related liver disease were not given HBIG. Nineteen patients received a combination of lamivudine and adefovir, 42 received entecavir, 12 received tenofovir, and 2 received a combination of entecavir and tenofovir. At the last follow-up (median = 21 months, range = 1–83 months), all patients were HBV DNA–negative. Sixty-six patients cleared hepatitis B surface antigen (HBsAg), and 19 patients formed antibody to hepatitis B surface antigen (anti-HBs). The cumulative probabilities of clearing HBsAg were 90% and 92% at 1 and 2 years after transplantation, respectively. Nine patients were HBsAg-positive with undetectable DNA at the last follow-up. The recurrence rate in our series was 8% (6/75). Five of these 6 patients had stopped taking oral antivirals, and 1 had entecavir resistance. All recurrences were salvaged with changes in the oral antivirals. The actuarial probability of survival in this cohort was 73.7% at 83 months. There was no mortality due to HBV recurrence. In conclusion, HBV prophylaxis with oral antivirals and without HBIG is safe and effective in LRLT. A majority of the patients will clear HBsAg, and some will develop anti-HBs antibodies. Liver Transpl 19:1030–1035, 2013. © 2013 AASLD.
VEGFA, FLT1, KDR and colorectal cancer: Assessment of disease risk, tumor molecular phenotype, and survival
Authors: Slattery Martha L. , Lundgreen Abbie , Wolff Roger K.
Published: June 2013

Angiogenesis is essential for tumor progression. Vascular endothelial growth factor (VEGFA) and its receptors 1 (FLT1) and 2 (KDR), have been identified as major mediators of this process. We hypothesized that genetic variation inFLT1(38SNPs),KDR(22 SNPS), andVEGFA(11 SNPs) would be associated with colon and rectal cancer development and survival. Data from a case–control study of 1555 colon cancer cases and 1956 controls and 754 rectal cancer cases and 959 controls were used. An adaptive rank truncation product (ARTP), based on 10 000 permutations, was used to determine the statistical significance of the candidate genes and angiogenesis pathway. Based on ARTP results,FLT1was significantly associated with risk of colon cancer (PARTP = 0.045) andVEGFAwas significantly associated with rectal cancer (PARTP = 0.036). After stratifying by tumor molecular subtype, SNP associations observed for colon cancer were:VEGFArs2010963 with CIMP+ colon tumors;FLT1rs4771249 and rs7987649 withTP53;FLT1 rs3751397,rs7337610,rs7987649, andrs9513008andKDRrs10020464, rs11941492, and rs12498529 with MSI+ and CIMP+/KRAS2‐mutated tumors.FLT1rs2296189 and rs600640 were associated with CIMP+ rectal tumors andFLT1rs7983774 was associated withTP53‐mutated rectal tumors. Four SNPs inFLT1were associated with colon cancer survival while three SNPs inKDRwere associated with survival after diagnosis with rectal cancer. Aspirin/NSAID use, smoking cigarettes, and BMI modified the associations. These findings suggest the importance of inflammation and angiogenesis in the etiology of colorectal cancer and that genetic and lifestyle factors may be targets for modulating disease risk. © 2013 Wiley Periodicals, Inc.
Boards, Auditors, Attorneys and Compliance with Mandatory SEC Disclosure Rules
Authors: Choudhary Preeti , Schloetzer Jason D. , Sturgess Jason D.
Published: June 2013

We survey the empirical literature on the determinants of firms' compliance with mandatory SEC disclosure rules. We begin with a discussion of the role of boards of directors, public accounting firms, and corporate attorneys in the preparation and review of mandatory disclosures. We then organize current research into three broad types of variation in compliance:completeness,timelinessandreadability. Our review highlights three interesting areas for future research: (1) studies that examine the relations between completeness, timeliness and readability within the same research design; (2) studies that assess whether boards of directors, public accounting firms and corporate attorneys view disclosure compliance as a general firm policy; and (3) studies that investigate the influence of corporate attorneys on mandatory disclosure, as well as studies of disclosure issues that require collaboration between auditors and corporate attorneys. As a first step to address the latter agenda, we provide new empirical evidence regarding the impact of corporate attorneys on disclosure compliance. Copyright © 2013 John Wiley & Sons, Ltd.
Short‐term in vitro culturing improves transplantability of type A spermatogonia in rainbow trout (Oncorhynchus mykiss)
Authors: Shikina Shinya , Nagasawa Kazue , Hayashi Makoto , Furuya Maki , Iwasaki Yoshiko , Yoshizaki Goro
Published: June 2013

Continuous production of sperm within the testes is supported by spermatogonial stem cells capable of both self‐renewal and the production of numerous differentiated germ cells. We previously demonstrated that a subpopulation of trout type A spermatogonia transplanted into the body cavity of a recipient embryo incorporated into the genital ridge, where they produced functional gametes within the gonads. Various cell‐surface proteins could have played a role in the incorporation of spermatogonia into recipient genital ridges. During the preparation of cell suspensions for transplantation in our experimental protocol, however, dissociation of testis by strong proteases was unavoidable. This was problematic as cell‐surface proteins may have been at least partially digested by protease activity. In the present study, recovery of spermatogonial surface proteins using short‐term culture prior to transplantation was attempted. It was found that spermatogonia cultured in vitro could be harvested by ethylenediaminetetraacetic acid (EDTA) instead of protease treatment. Furthermore, when cultured spermatogonia collected by EDTA treatment were maintained for 24 hr in vitro, they exhibited high adhesiveness. These cultured spermatogonia also possessed higher survival of transplantation compared to spermatogonia newly dispersed by trypsin treatment. These results indicated that spermatogonia possess a reduced ability to migrate toward, adhere to, and/or be incorporated into the recipient genital ridge immediately after protease treatment. Short‐term in vitro culturing, however, could allow spermatogonia to recover the surface proteins required for successful incorporation into the recipient genital ridge.Mol. Reprod. Dev. 80: 763–773, 2013. © 2013 Wiley Periodicals, Inc.
Reversible effects of oxygen partial pressure on genes associated with placental angiogenesis and differentiation in primary‐term cytotrophoblast cell culture
Authors: Debiève F. , Depoix C. , Gruson D. , Hubinont C.
Published: June 2013

Timely regulated changes in oxygen partial pressure are important for placental formation. Disturbances could be responsible for pregnancy‐related diseases like preeclampsia and intrauterine growth restriction. We aimed to (i) determine the effect of oxygen partial pressure on cytotrophoblast differentiation; (ii) measure mRNA expression and protein secretion from genes associated with placental angiogenesis; and (iii) determine the reversibility of these effects at different oxygen partial pressures. Term cytotrophoblasts were incubated at 21% and 2.5% O2 for 96 hr, or were switched between the two oxygen concentrations after 48 hr. Real‐time PCR and enzyme‐linked immunosorbent assays (ELISAs) were used to evaluate cell fusion and differentiation, measuring transcript levels for those genes involved in cell fusion and placental angiogenesis, including VEGF, PlGF, VEGFR1, sVEGFR1, sENG, INHA, and GCM1. Cytotrophoblasts underwent fusion and differentiation in 2.5% O2. PlGF expression was inhibited while sVEGFR1 expression increased. VEGF and sENG mRNA expressions increased in 2.5% compared to 21% O2, but no protein was detected in the cell supernatants. Finally, GCM1 mRNA expression increased during trophoblast differentiation at 21% O2, but was inhibited at 2.5% O2. These mRNA expression effects were reversed by returning the cells to 21% O2. Thus, low‐oxygen partial pressure does not inhibit term‐cytotrophoblast cell fusion and differentiation in vitro. Lowering the oxygen partial pressure from 21% to 2.5% caused normal‐term trophoblasts to reversibly modify their expression of genes associated with placental angiogenesis. This suggests that modifications observed in pregnancy diseases such as preeclampsia or growth retardation are probably due to an extrinsic effect on trophoblasts. Mol. Reprod. Dev. 80: 774–784, 2013. © 2013 Wiley Periodicals, Inc.
Prospective association of protein intake during puberty with body composition in young adulthood
Authors: Assmann K.E. , Joslowski G. , Buyken A.E. , Cheng G. , Remer T. , Kroke A. , Günther A.L.B.
Published: June 2013

Objective

To examine the association of habitual animal and plant protein intake during the potentially critical period of puberty with body composition in young adulthood.

Design and Methods

Multivariable regression analyses were performed on data from 140 female and 122 male participants of the DONALD Study with ≥2 3‐day weighed dietary records during puberty (girls 9‐14 years; boys 10‐15 years) and anthropometric measurements in young adulthood (18‐25 years). Fat‐free mass index (FFMI) and fat mass index (FMI) were estimated from four skinfolds.

Results

In women, a higher pubertal animal protein consumption was independently related to higher levels of FFMI (ptrend = 0.001), but not to FMI (ptrend = 0.5). Adjusted means of FFMI in energy‐adjusted tertiles of animal protein intake were 15.3 (95% confidence interval: 15.0, 15.5), 15.4 (15.1, 15.7), 16.2 (15.9, 16.6) kg/m2. In men, a higher animal protein intake was related to a higher FFMI (ptrend = 0.04) and a lower FMI (ptrend = 0.001) only after adjusting FFMI for current FMI levels and vice versa. Plant protein was not associated with body composition among either sex.

Conclusions

Our results show that a higher pubertal animal protein consumption may yield a higher fat‐free mass in young adulthood.
An 8‐month randomized controlled exercise trial alters brain activation during cognitive tasks in overweight children
Authors: Krafft Cynthia E. , Schwarz Nicolette F. , Chi Lingxi , Weinberger Abby L. , Schaeffer David J. , Pierce Jordan E. , Rodrigue Amanda L. , Yanasak Nathan E. , Miller Patricia H. , Tomporowski Phillip D. , Davis Catherine L. , McDowell Jennifer E.
Published: June 2013

Objective

Children who are less fit reportedly have lower performance on tests of cognitive control and differences in brain function. This study examined the effect of an exercise intervention on brain function during two cognitive control tasks in overweight children.

Design and Methods

Participants included 43 unfit, overweight (BMI ≥ 85th percentile) children 8‐ to 11‐years old (91% Black), who were randomly divided into either an aerobic exercise (n = 24) or attention control group (n = 19). Each group was offered a separate instructor‐led after‐school program every school day for 8 months. Before and after the program, all children performed two cognitive control tasks during functional magnetic resonance imaging (fMRI): antisaccade and flanker.

Results

Compared to the control group, the exercise group decreased activation in several regions supporting antisaccade performance, including precentral gyrus and posterior parietal cortex, and increased activation in several regions supporting flanker performance, including anterior cingulate and superior frontal gyrus.

Conclusions

Exercise may differentially impact these two task conditions, or the paradigms in which cognitive control tasks were presented may be sensitive to distinct types of brain activation that show different effects of exercise. In sum, exercise appears to alter efficiency or flexible modulation of neural circuitry supporting cognitive control in overweight children.
Photogeneration of carbocations: applications in physical organic chemistry and the design of suitable precursors
Authors: Ammer Johannes , Mayr Herbert
Published: June 2013

The generation of carbocations by laser flash photolysis of suitable precursors provides information about their reactivities toward nucleophiles on the nanosecond and microsecond time scale that cannot be obtained by conventional methods. We discuss the requirements that must be met by the precursors to achieve sufficient yields of the carbocations under the conditions of kinetic experiments. These include (i) efficient photogeneration of the carbocations; (ii) the stability of the precursor in the sample solution; (iii) the absorption of the precursor at the excitation wavelength; and (iv) sufficient lifetimes of the photogenerated carbocations for the observation of their reactivities toward the nucleophiles of interest. We provide an overview of the advantages and disadvantages of some precursors that are commonly employed for the generation of carbocations R+. This includes alkyl halides R–Cl, acetates R–OAc, aryl ethers R–OAr, ammonium salts R–NR′3+, and phosphonium salts R–PR′3+. Copyright © 2013 John Wiley & Sons, Ltd.
QM/MM kinetic isotope effects for chloromethane hydrolysis in water
Authors: Javier Ruiz Pernía J. , Ruggiero Giuseppe D. , Williams Ian H.
Published: June 2013

Computational simulations for chloromethane hydrolysis have been performed using hybrid quantum‐mechanical/molecular‐mechanical methods with explicit solvation by large numbers of water molecules. In the first part of the paper, we present results for 2° 2H3, 1° 14C, and 1° 37Cl kinetic isotope effects (KIEs) at 298 K with both the AM1/TIP3P and B3LYP/6‐31G* QM methods for the nucleophile H2O and electrophile CH3Cl surrounded by 496 solvating TIP3P water molecules. An initial Hessian computed for a subset of this system including up to 104 MM water molecules was reduced in size by successive deletion of rows and columns, and KIEs were evaluated for each. We suggest that accurate calculations of KIEs in solvated systems should involve a subset Hessian including the substrate together with any solvent atoms making specific interactions with any isotopically substituted atom. In the second part of the paper, the ensemble‐averaged 2° α‐2H3 KIE calculated with the B3LYP/6‐31+G(d,p)/TIP3P method is shown to be in good agreement with experiment. This comparison is meaningful because it includes consideration of uncertainties owing to sampling of a range of representative thermally accessible solvent configurations. We also present ensemble‐averaged 14C and 37Cl KIEs which have not as yet been determined experimentally. Copyright © 2013 John Wiley & Sons, Ltd.
Magnetic Nanocomposites Formed by FeNi3 Nanoparticles Embedded in Graphene. Application as Supercapacitors
Authors: Abellán Gonzalo , Coronado Eugenio , Martí‐Gastaldo Carlos , Ribera Antonio , Otero Toribio F.
Published: June 2013

A general family of magnetic nanocomposites formed by FeNi3 ferromagnetic nanoparticles (NPs) embedded in a graphitized carbon matrix is reported. The soft chemical approach used relies on the catalytic effect of the NPs resulting from the thermal decomposition of the layered double hydroxide precursor, which acts as a multilayered nanoreactor enabling the formation of a range of carbon nanoforms (CNFs). This is followed by acid treatment of the as‐prepared nanocomposites to isolate the different CNFs formed. These range from carbon nano‐onions to graphene depending on the temperature of the thermal decomposition. This synthetic process paves the way for the rational design of metal–carbon nanocomposites with controllable composition as precursors of nanocarbons or even graphene. The coexistence of metal NPs and nanostructured carbon is a major source of applications. As a proof of concept, the electrochemical performance of these metal–carbon hybrid supercapacitors is studied under high discharging current densities and they exhibit high values of specific capacitance and excellent rate capabilities.
Disseminated, large‐sized neonatal pneumatoceles: The wait‐and‐see strategy
Authors: Maranella E. , Conte E. , Di Natale C. , Coclite E. , Di Fabio S.
Published: June 2013

Pulmonary pneumatoceles are thin‐walled, air‐filled cysts that develop within the lung parenchyma. Most often, they occur as a sequel of acute pneumonia, commonly caused by Staphylococcus aureus in children. Limited data are available about infective pulmonary cysts in newborns. We report a case of a newborn, who developed multiple pneumatoceles after Escherichia coli pneumonia. Pediatr Pulmonol. 2014; 49:E69–E71. © 2013 Wiley Periodicals, Inc.
Can proteomics yield insight into aging aorta?
Authors: Fu Zongming , Wang Mingyi , Everett Allen , Lakatta Edward , Van Eyk Jennifer
Published: June 2013

The aging aorta exhibits structural and physiological changes that are reflected in the proteome of its component cells types. The advance in proteomic technologies has made it possible to analyze the quantity of proteins associated with the natural history of aortic aging. These alterations reflect the molecular and cellular mechanisms of aging and could provide an opportunity to predict vascular health. This paper focuses on whether discoveries stemming from the application of proteomic approaches of the intact aging aorta or vascular smooth muscle cells can provide useful insights. Although there have been limited studies to date, a number of interesting proteins have been identified that are closely associated with aging in the rat aorta. Such proteins, including milk fat globule‐EGF factor 8, matrix metalloproteinase type‐2, and vitronectin, could be used as indicators of vascular health, or even explored as therapeutic targets for aging‐related vascular diseases.
Metallothionein 3: An androgen‐upregulated gene enhances cell invasion and tumorigenesis of prostate carcinoma cells
Authors: Juang Horng‐Heng , Chung Li‐Chuan , Sung Hsin‐Ching , Feng Tsui‐Hsia , Lee Yi‐Hua , Chang Phei‐Lang , Tsui Ke‐Hung
Published: June 2013

BACKGROUND

Metallothioneins (MT1, MT2, MT3, and MT4) are regarded as modulators regulating a number of biological processes including cell proliferation, differentiation, and invasion. We determined the effects of androgen, cadmium, and arsenic on MT1/2 and MT3 in prostate carcinoma cells, and evaluated the functional effects of MT3 on cell proliferation, invasion, and tumorigenesis.

METHODS

We determined the expression of MT1/2 and MT3 in prostate carcinoma cells by immunoblotting assays or real‐time reverse transcription‐polymerase chain reactions. The effects of ectopic MT3 overexpression or MT3‐knockdown on cell proliferation, invasion, and tumorigenesis were determined by 3H‐thymidine incorporation, matrigel invasion, and murine xenograft studies. The effects of androgen, cadmium, and arsenic on target genes were assessed using immunoblotting and reporter assays.

RESULTS

Androgen, cadmium, and arsenic treatments enhanced gene expression of MT1/2 and MT3 in prostate carcinoma LNCaP cells. Results of immunohistochemical staining indicated MT3 overexpression was found predominantly in the nuclear areas of PC‐3 cells overexpressing MT3. Overexpression of MT3 significantly increased cell proliferation, invasion, and tumorigenic activities in PC‐3 cells in vitro and in vivo. MT3 overexpression downregulated the gene expressions of N‐myc downstream regulated gene 1 (Ndrg1) and maspin, and attenuated blocking effects of doxorubicin in PC‐3 cells on cell proliferation. MT3‐knockdown enhanced Ndrg1 and maspin expressions in LNCaP cells.

CONCLUSIONS

The experiments indicate that MT3 is an androgen‐upregulated gene, and promotes tumorigenesis of prostate carcinoma cells. The downregulation of Ndrg1 and maspin gene expressions appears to account for the enhancement of proliferative and invasive functions of MT3 in PC‐3 cells. Prostate 73: 1495–1506, 2013 © 2013 Wiley Periodicals, Inc.
Plasmonic sensors based on thick metal film perforated with rectangular nanohole arrays
Authors: Yuan Li , Chen Fuyi
Published: June 2013

The dependence of optical properties on the ambient medium, the period of nanohole arrays and the metal film thickness in a thick silver film perforated with rectangular nanohole arrays is investigated using the finite‐difference time‐domain technique. As a result of the coupling between top and down surface plasmon polaritons, mediated by localized surface plasmon resonances supported by the metallic rectangular nano‐ holes, interesting light phenomena are observed for varying thickness of the metal film and period of the rectangular nanohole arrays. Based on the dependence of the optical properties on the ambient medium, the possibility of exploiting thick metal rectangular nanohole arrays as plasmonic sensors is further discussed, the potential application as plasmonic sensors is revealed. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Fabricating organic transistors based on domain‐ordered copper phthalocyanine film grown on oligothiophene epitaxial substrate
Authors: Hu Yulei , Gu Wen , Liu Na , Zhu Zongpeng , Zhang Jianhua , Wang Jun
Published: June 2013

Organic field‐effect transistors were fabricated using a domain‐ordered copper phthalocyanine (CuPc) thin film as the active layer prepared by weak epitaxial growth (WEG) technology. CuPc was deposited onto α‐sexithiophene (α‐6T) and α,ω‐dihexylsexithiophene (α,ω‐DH6T) films acting as the epitaxial substrate to realize the domain‐order growth. As a result, the thin‐film morphology of CuPc exhibits many re‐ gional domain‐ordered structures measured by atomic force microscopy and X‐ray diffraction. The field‐effect mobilities are 0.11 and 0.085 cm2/Vs for the devices with CuPc/α‐6T and CuPc/α,ω‐DH6T, respectively. The threshold voltages were –7 V and –13 V for CuPc/α‐6T and CuPc/α,ω‐DH6T, respectively. The improved device performance could be attributed to the domain‐order structure of the CuPc thin film. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Gd3+ to Ce3+ energy transfer in multi‐component GdLuAG and GdYAG garnet scintillators
Authors: Kučera Miroslav , Nikl Martin , Hanuš Martin , Onderišinová Zuzana
Published: June 2013

Optical and luminescence properties were studied in the Ce3+ doped yttrium and lutetium aluminum garnets (YAG, LuAG) admixed by Gd3+ and Ga3+ ions. The single crystalline films were grown by liquid phase epitaxy. Energy transfer from Gd3+ sensitizer to Ce3+ activator ions was established. This energy transfer was observed in a broad range of Gd concentrations which may point to longer range interaction between Gd3+ and Ce3+ ions.

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(© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On increasing global temperatures: 75 years after Callendar
Authors: Hawkins Ed , Jones Phil. D.
Published: June 2013

In 1938, Guy Stewart Callendar was the first to demonstrate that the Earth's land surface was warming. Callendar also suggested that the production of carbon dioxide by the combustion of fossil fuels was responsible for much of this modern change in climate. This short note marks the 75th anniversary of Callendar's landmark study and demonstrates that his global land temperature estimates agree remarkably well with more recent analyses.
Estimating interchannel observation‐error correlations for IASI radiance data in the Met Office system†
Authors: Stewart L. M. , Dance S. L. , Nichols N. K. , Eyre J. R. , Cameron J.
Published: June 2013

The optimal utilisation of hyper‐spectral satellite observations in numerical weather prediction is often inhibited by incorrectly assuming independent interchannel observation errors. However, in order to represent these observation‐error covariance structures, an accurate knowledge of the true variances and correlations is needed. This structure is likely to vary with observation type and assimilation system. The work in this article presents the initial results for the estimation of IASI interchannel observation‐error correlations when the data are processed in the Met Office one‐dimensional (1D‐Var) and four‐dimensional (4D‐Var) variational assimilation systems. The method used to calculate the observation errors is a post‐analysis diagnostic which utilises the background and analysis departures from the two systems.

The results show significant differences in the source and structure of the observation errors when processed in the two different assimilation systems, but also highlight some common features. When the observations are processed in 1D‐Var, the diagnosed error variances are approximately half the size of the error variances used in the current operational system and are very close in size to the instrument noise, suggesting that this is the main source of error. The errors contain no consistent correlations, with the exception of a handful of spectrally close channels. When the observations are processed in 4D‐Var, we again find that the observation errors are being overestimated operationally, but the overestimation is significantly larger for many channels. In contrast to 1D‐Var, the diagnosed error variances are often larger than the instrument noise in 4D‐Var. It is postulated that horizontal errors of representation, not seen in 1D‐Var, are a significant contributor to the overall error here. Finally, observation errors diagnosed from 4D‐Var are found to contain strong, consistent correlation structures for channels sensitive to water vapour and surface properties.
Improved Fast Initial Response Features for Exponentially Weighted Moving Average and Cumulative Sum Control Charts
Authors: Haq Abdul , Brown Jennifer , Moltchanova Elena
Published: June 2013

Exponentially weighted moving average (EWMA) and cumulative sum (CUSUM) control charts have found extensive applications in industry. The sensitivity of these quality control schemes can be increased by using fast initial response (FIR) features. In this paper, we introduce some improved FIR features for EWMA and CUSUM control charts and evaluate their performance in terms of average run length. We compare the proposed FIR‐based EWMA and CUSUM control schemes with some existing control schemes, that is, EWMA, FIR‐EWMA, CUSUM, and FIR‐CUSUM. It is noteworthy that the proposed control schemes are uniformly better than the other schemes considered here. An illustrative example is also given to demonstrate the implementation of the proposed control schemes. Copyright © 2013 John Wiley & Sons, Ltd.
A seamless soft handover management scheme in NGEO satellite networks
Authors: Wang Lu , Li Xiangqun , Liu Lixiang , Hu Xiaohui
Published: June 2013

Satellite networks can provide extensive geographic coverage to diverse user population, but handovers of active communications should be controlled considering the satellites' high speed. Mobile IP and many other handover algorithms have been proposed for terrestrial wireless networks. However, the satellite network exhibits several unique features compared with the terrestrial wireless networks, such as the long delay. This paper proposes a seamless soft handover scheme (S2H) for satellite networks. S2H designs an identity locator split addressing to solve the multihoming problem and applies the network coding scheme during handover. This manner is able to reduce the interference opportunity, save transmissions, and achieve low handover delay, short queue length, and high throughput. Relying on the simulation results, S2H is able to achieve better performance compared with the proposed handover algorithms in the satellite environment when there are multiple traffic flows. Copyright © 2013 John Wiley & Sons, Ltd.