bluuebunny/crossref_metadata_2025 huggingface dataset:
Buckybowls as adsorbents forCO2, CH4, and C2H2: Binding and structural insights from computational study
Authors: Hussain M. Althaf , Vijay Dolly , Sastry G. Narahari
Published: October 2015

Noncovalent functionalization of buckybowls sumanene (S), corannulene (R), and coronene (C) with greenhouse gases (GGs) such as CO2, CH4(M), and C2H2(A) has been studied using hybrid density functional theory. The propensity and preferences of these small molecules to interact with the concave and convex surfaces of the buckybowls has been quantitatively estimated. The results indicate that curvature plays a significant role in the adsorption of these small molecules on the π surface and it is observed that buckybowls have higher binding energies (BEs) compared with their planar counterpart coronene. The concave surface of the buckybowl is found to be more feasible for adsorption of small molecules. BEs of small molecules towards π systems is CO2 > A > M and the BEs of π systems toward small molecules is S > R > C. Obviously, the binding preference is dictated by the way in which various noncovalent interactions, such as π···π, lone pair···π, and CH···π manifest themselves on carbaneous surfaces. To delineate the intricate details of the interactions, we have employed Bader's quantum theory of atoms in molecule and localized molecular orbital energy decomposition analysis (LMO‐EDA). LMO‐EDA, which measures the contribution of various components and traces the physical origin of the interactions, indicates that the complexes are stabilized largely by dispersion interactions. © 2015 Wiley Periodicals, Inc.
Application of zone‐folding approach to the first‐principles estimation of thermodynamic properties of carbon and ZrS2‐based nanotubes
Authors: Bandura Andrei V. , Porsev Vitaly V. , Evarestov Robert A.
Published: October 2015

A zone‐folding (ZF) approach is applied for the estimation of the phonon contributions to thermodynamic properties of carbon‐and ZrS2‐based nanotubes (NTs) of hexagonal morphology with different chiralities. The results obtained are compared with those from the direct calculation of the thermodynamic properties of NTs using PBE0 hybrid exchange‐correlation functional. The phonon contribution to the stability of NTs proved to be negligible for the internal energy and small for the Helmholtz free energy. It is found that the ZF approach allows us an accurate estimation of phonon contributions to internal energy, but slightly overestimates the phonon contributions to entropy. © 2015 Wiley Periodicals, Inc.
The Transcription Factor EB (TFEB) Regulates Osteoblast Differentiation Through ATF4/CHOP‐Dependent Pathway
Authors: Yoneshima Erika , Okamoto Kuniaki , Sakai Eiko , Nishishita Kazuhisa , Yoshida Noriaki , Tsukuba Takayuki
Published: October 2015

Osteoblasts are bone‐forming cells that produce large amounts of collagen type I and various bone matrix proteins. Although osteoblast differentiation is highly regulated by various factors, it remains unknown whether lysosomes are directly involved in osteoblast differentiation. Here, we demonstrate the transcription factor EB (TFEB), a master regulator of lysosomal biogenesis, modulates osteoblast differentiation. The expression levels of TFEB as well as those of endosomal/lysosomal proteins were up‐regulated during osteoblast differentiation using mouse osteoblastic MC3T3‐E1 cells. By gene knockdown (KD) experiments with small interfering RNA (siRNA), TFEB depletion caused markedly reduced osteoblast differentiation as compared with the control cells. Conversely, overexpression (OE) of TFEB resulted in strikingly enhanced osteoblastogenesis compared to the control cells. By analysis of down‐stream effector molecules, TFEB KD was found to cause marked up‐regulation of activating transcription factor 4 (ATF4) and CCAAT/enhancer‐binding protein homologous protein (CHOP), both of which are essential factors for osteoblastogenesis. In contrast, TFEB OE promoted osteoblast differentiation through reduced expression of ATF4 and CHOP without differentiation agents. Given the importance of ATF4 and CHOP in osteoblastogenesis, it is clear that the TFEB‐regulated signaling pathway for osteoblast differentiation is involved in ATF4/CHOP‐dependent signaling pathway. J. Cell. Physiol. 231: 1321–1333, 2016. © 2015 Wiley Periodicals, Inc.
A facile method to compare EFTEM maps obtained from materials changing composition over time
Authors: Casu Alberto , Genovese Alessandro , Di Benedetto Cristiano , Lentijo Mozo Sergio , Sogne Elisa , Zuddas Efisio , Falqui Andrea
Published: October 2015

Energy Filtered Transmission Electron Microscopy (EFTEM) is an analytical tool that has been successfully and widely employed in the last two decades for obtaining fast elemental maps in TEM mode. Several studies and efforts have been addressed to investigate limitations and advantages of such technique, as well as to improve the spatial resolution of compositional maps. Usually, EFTEM maps undergo post‐acquisition treatments by changing brightness and contrast levels, either via dedicated software or via human elaboration, in order to maximize their signal‐to‐noise ratio and render them as visible as possible. However, elemental maps forming a single set of EFTEM images are usually subjected to independent map‐by‐map image treatment. This post‐acquisition step becomes crucial when analyzing materials that change composition over time as a consequence of an external stimulus, because the map‐by‐map approach doesn't take into account how the chemical features of the imaged materials actually progress, in particular when the investigated elements exhibit very low signals. In this article, we present a facile procedure applicable to whole sets of EFTEM maps acquired on a sample that is evolving over time. The main aim is to find a common method to treat the images features, in order to make them as comparable as possible without affecting the information there contained. Microsc. Res. Tech. 78:1090–1097, 2015. © 2015 Wiley Periodicals, Inc.
Testing anti‐HIV activity of antiretroviral agents in vitro using flow cytometry analysis of CEM‐GFP cells infected with transfection‐derived HIV‐1 NL4‐3
Authors: Frezza Caterina , Grelli Sandro , Federico Maurizio , Marino‐Merlo Francesca , Mastino Antonio , Macchi Beatrice
Published: October 2015

An assay, specifically optimized to evaluate the anti‐HIV activity of antiretrovirals by flow cytometry analysis, is described. As widely used anti‐HIV agents, zidovudine (AZT), abacavir (ABC), 2′,3′‐dideoxyinosine (DDI), lamivudine (3TC), nevirapine (NVP), and efavirenz (EFV), and as drugs of recent approval raltegravir (RAL), etravirine (ETR), and rilpivirine (RPV), were utilized as reference drugs. HIV‐1 NL4‐3 virus was prepared by transfection of HEK293T cells with purified plasmid DNA and quantified by p24 antigen‐capture assay. For infection, CEM‐GFP cells were exposed to vehicle or to several concentrations of the drugs for 2 hr at 37°C before HIV‐1 NL4‐3 was added to each sample. The adsorption was prolonged for 3 hr at 37°C. After 72 hr of incubation, HIV‐induced GFP expression in infected CEM‐GFP cells was assessed by flow cytometry analysis and expressed as % positive cells. For comparison, p24 production in supernatants was assessed by a commercial ELISA kit. On the basis of IC50 values, the anti‐HIV activity, as assayed by this method, was EFV > 3TC > AZT > NVP > DDI > ABC and ETR > RPV > RAL. The comparison between the IC50 values calculated through flow cytometry and p24 production revealed overlapping results, showing that the optimized protocol of CEM‐GFP infection with HIV NL4‐3 is a suitable method to perform quantitative, rapid and low‐expensive screening tests to evaluate the in vitro effect of new candidate anti‐HIV drugs. J. Med. Virol. 88:979–986, 2016. © 2015 Wiley Periodicals, Inc.
Increased expression and dysregulated association of restriction factors and type I interferon in HIV, HCV mono‐ and co‐infected patients
Authors: Zhu Jia‐Wu , Liu Feng‐Liang , Mu Dan , Deng De‐Yao , Zheng Yong‐Tang
Published: October 2015

Host restriction factors and type I interferon are important in limiting HIV and HCV infections, yet the role of HIV, HCV mono‐ and co‐infection in regulating these antiviral genes expression is not clear. In this study, we measured the levels of TRIM5α, TRIM22, APOBEC3G, and IFN‐α, ‐β mRNA expression in peripheral blood mononuclear cells of 43 HIV mono‐infected, 70 HCV mono‐infected and 64 HIV/HCV co‐infected patients along with 98 healthy controls. We also quantified HIV and HCV viral loads in mono‐ and co‐infected patients. The results showed that HCV, HIV mono‐ and co‐infection differentially increased TRIM22, APOBEC3G, and IFN‐α, ‐β mRNA expression while the mRNA expression of TRIMα was upregulated only by HCV‐mono infection. HIV/HCV co‐infection was associated with higher viral load, compared to either HIV or HCV mono‐infection. Additionally, we showed TRIMα and TRIM22 positively correlated with IFN‐α, ‐β, which could be dysregulated by HIV, HCV mono‐ and co‐infection. Furthermore, we found TRIM22 negatively correlated with HCV viral load in mono‐infected patients and APOBEC3G positively correlated with HCV viral load in co‐infected patients. Collectively, our findings suggest the potential role of restriction factors in restricting HIV, HCV mono‐ and co‐infection in vivo, which appears to be a therapeutic target for potential drug discovery. J. Med. Virol. 88:987–995, 2016. © 2015 Wiley Periodicals, Inc.
Risk of congenital cytomegalovirus infection among HIV‐exposed uninfected infants is not decreased by maternal nelfinavir use during pregnancy
Authors: Gantt Soren , Leister Erin , Jacobsen Denise L. , Boucoiran Isabelle , Huang Meei‐Li , Jerome Keith R. , Jourdain Gonzague , Ngo‐Giang‐Huong Nicole , Burchett Sandra , Frenkel Lisa
Published: October 2015

Background: Congenital cytomegalovirus (cCMV) infection is common among infants born to HIV‐infected women. Nelfinavir (NFV), an antiretroviral drug that is safe during pregnancy, inhibits CMV replication in vitro at concentrations that standard doses achieve in plasma. We hypothesized that infants born to women receiving NFV for prevention of mother‐to‐child transmission of HIV (PMTCT) would have a reduced prevalence of cCMV infection. Methods: The prevalence of cCMV infection was compared among HIV‐uninfected infants whose HIV‐infected mothers either received NFV for >4 weeks during pregnancy (NFV‐exposed) or did not receive any NFV in pregnancy (NFV‐unexposed). CMV PCR was performed on infant blood samples collected at <3 weeks from birth. Results: Of the 1,255 women included, 314 received NFV for >4 weeks during pregnancy and 941 did not receive any NFV during pregnancy. The overall prevalence of cCMV infection in the infants was 2.2%, which did not differ by maternal NFV use. Maternal CD4 T cell counts were inversely correlated with risk of cCMV infection, independent of the time NFV was initiated during gestation. Infants with cCMV infection were born 0.7 weeks earlier (P = 0.010) and weighed 170 g less (P = 0.009) than uninfected infants. Conclusion: Among HIV‐exposed uninfected infants, cCMV infection was associated with adverse perinatal outcomes. NFV use in pregnancy was not associated with protection against cCMV. Safe and effective strategies to prevent cCMV infection are needed. J. Med. Virol. 88:1051–1058, 2016. © 2015 Wiley Periodicals, Inc.
Susceptibility of HPV16 and 18 to high level disinfectants indicated for semi‐critical ultrasound probes
Authors: Ryndock Eric , Robison Richard , Meyers Craig
Published: October 2015

Ultrasound probes used in endocavitary procedures have been shown to be contaminated with high‐risk HPV after routine use and HPV is also known to be resistant to some high level disinfectants (HLDs). This study compared efficacy of two leading ultrasound probe HLD methods; liquid ortho‐phthalaldehyde (Cidex® OPA) and an automated device using sonicated hydrogen peroxide (trophon® EPR) against HPV16 and HPV18 in a hard‐surface carrier test. Native HPV16 and HPV18 virions were generated in organotypic epithelial raft cultures. Viral lysates were dried onto carriers with a 5% (v/v) protein soil. Efficacy tests were performed against the automated device at 35% and 31.5% H2O2 and 0.55% OPA in quadruplicate with matched input, neutralization, and cytotoxicity controls. Hypochlorite was included as a positive control. Infectivity was determined by the abundance (qRT‐PCR) of the spliced E1^E4 transcript in infected recipient cells. The automated HLD device showed excellent efficacy against HPV16 and HPV18 (>5 log10 reductions in infectivity) whereas OPA showed minimal efficacy (<0.6 log10 reductions). While HPV is highly resistant to OPA, sonicated hydrogen peroxide offers an effective disinfection solution for ultrasound probes. Disinfection methods that are effective against HPV should be adopted where possible. J. Med. Virol. 88:1076–1080, 2016. © 2015 The Authors. Journal of Medical Virology Published by Wiley Periodicals, Inc.
Human papillomavirus infection in male patients with STI‐related symptoms in Hanoi, Vietnam
Authors: Le Hai Ha Long , Bi Xiuqiong , Ishizaki Azumi , Van Le Hung , Nguyen Trung Vu , Hosaka Norimitsu , Ichimura Hiroshi
Published: October 2015

This cross‐sectional study investigated the prevalence, genotypes, and risk factors for human papillomavirus (HPV) infection in Hanoi, Vietnam. The study included 192 males (mean age, 32.9 years) with symptoms related to sexually transmitted infections (STI). Urinary, penile, and urethral samples were collected in April and May, 2014. HPV DNA was detected with PCR, performed with modified and/or original GP5+/GP6+ primers. HPV genotypes were determined with a gene array assay. Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) DNA were detected with loop‐mediated isothermal amplification. HPV DNA, NG, and CT were detected in 48 (25.0%), 23 (12.0%), and 41 (21.4%) patients, respectively. HPV DNA appeared in penile samples (21.0%, 39/186) more frequently than in urinary (3.1%, 6/191, P < 0.001) and urethral (9.4%, 18/192, P = 0.002) samples. Among patients with HPV, genotype prevalence was: HPV81 (22.9%),  HPV52 (18.8%), HPV18 (16.7%), and HPV16 (6.3%). Multiple‐type and high risk‐type HPV infections were determined in 33.3% and 64.6%, respectively. Multivariate analysis showed a significant association of HPV infection in urethra with younger sexual debut age. HPV52 was the most prevalent high‐risk HPV genotype, whereas HPV16 was less common in the male Vietnamese patients with STI‐related symptoms. Younger sexual‐debut age was a risk factor for HPV infection in urethra. J. Med. Virol. 88:1059–1066, 2016. © 2015 Wiley Periodicals, Inc.
Extraction of organophosphorus pesticides by carbon‐coated Fe3O4 nanoparticles through response surface experimental design
Authors: Maddah Bozorgmehr , Alidadi Sattar , Hasanzadeh Mahdi
Published: October 2015

In this paper, carbon‐coated Fe3O4 nanoparticles were successfully synthesized and used as a magnetic solid‐phase extraction absorbent for the preconcentration and extraction of organophosphorus pesticides in environmental water samples. The carbon‐coated Fe3O4 nanoparticles were characterized by transmission electron microscopy, X‐ray powder diffraction, Fourier transform infrared spectroscopy, and vibrating sample magnetometry. The determination of organophosphorus pesticides in water samples with carbon‐coated Fe3O4 nanoparticles was investigated by high‐performance liquid chromatography with a diode array detector. Furthermore, the response surface model based on the central composite design was applied to quantitatively investigate the effect of some important variables influencing the extraction efficiency, such as pH, treatment time, amount of nanoparticle sorbents, and amount of salt and to find the optimized conditions providing the highest extraction efficiency. Under optimized conditions, the calibration curve was linear in the range of 0.5–15.0 ng/mL with a regression coefficient of 0.9948, 0.9958, and 0.9931 for fenitrothion, diazinon, and ethion, respectively. The obtained results showed that this analytical method would be useful for the analysis of fenitrothion, diazinon, and ethion in tap water with high precision and accuracy.
Interferon‐free therapy for genotype 1 hepatitis C in liver transplant recipients: Real‐world experience from the hepatitis C therapeutic registry and research network
Authors: Brown Robert S. , O'Leary Jacqueline G. , Reddy K. Rajender , Kuo Alexander , Morelli Giuseppe J. , Burton James R. , Stravitz R. Todd , Durand Christine , Di Bisceglie Adrian M. , Kwo Paul , Frenette Catherine T. , Stewart Thomas G. , Nelson David R. , Fried Michael W. , Terrault Norah A. ,   on behalf of the Hepatitis C Therapeutic Registry Research Network Study Group
Published: October 2015

Recurrent infection with the hepatitis C virus (HCV) after liver transplantation (LT) is associated with decreased graft and patient survival. Achieving sustained virological response (SVR) with antiviral therapy improves survival. Because interferon (IFN)‐based therapy has limited efficacy and is poorly tolerated, there has been rapid transition to IFN‐free direct‐acting antiviral (DAA) regimens. This article describes the experience with DAAs in the treatment of posttransplant genotype (GT) 1 HCV from a consortium of community and academic centers (Hepatitis C Therapeutic Registry and Research Network [HCV‐TARGET]). Twenty‐one of the 54 centers contributing to the HCV‐TARGET consortium participated in this study. Enrollment criteria included positive posttransplant HCV RNA before treatment, HCV GT 1, and documentation of use of a simeprevir (SMV)/sofosbuvir (SOF) containing DAA regimen. Safety and efficacy were assessed. SVR was defined as undetectable HCV RNA 64 days or later after cessation of treatment. A total of 162 patients enrolled in HCV‐TARGET started treatment with SMV+SOF with or without ribavirin (RBV) following LT. The study population included 151 patients treated with these regimens for whom outcomes and safety data were available. The majority of the 151 patients were treated with SOF and SMV alone (n = 119; 79%) or with RBV (n = 32; 21%), The duration of therapy was 12 weeks for most patients, although 15 patients received 24 weeks of treatment. Of all patients receiving SOF/SMV with or without RBV, 133/151 (88%) achieved sustained virological response at 12 weeks after therapy and 11 relapsed (7%). One patient had virological breakthrough (n = 1), and 6 patients were lost to posttreatment follow‐up. Serious adverse events occurred in 11.9%; 3 patients (all cirrhotic) died due to aspiration pneumonia, suicide, and multiorgan failure. One experienced LT rejection. IFN‐free DAA treatment represents a major improvement over prior IFN‐based therapy. Broader application of these and other emerging DAA regimens in the treatment of posttransplant hepatitis C is warranted. Liver Transpl 22:24‐33, 2016. © 2015 AASLD.
Dynamics of Biopolymers: Role of Hydration and Electrostatic Interactions
Authors: Roh Joon Ho
Published: October 2015

This contribution highlights the recently developed microscopic picture of the effects of hydration and electrostatic interactions on subnanosecond dynamics of biopolymers protein and ribonucleic acid (RNA), studied by quasielastic neutron scattering spectroscopy. In contrast to the traditional concept of water‐slaved dynamics, more detailed analysis of the dynamics of different chemical structures (lysozyme vs transfer RNA; electrostatically unscreened vs screened) demonstrates that chemical and physical responses of biopolymers to hydration and charge screening determine the dynamic interactions. How the relationship of the dynamical flexibility and structural stability varies depending on water‐driven or charge screening‐driven folding into biologically active structures has also been discussed. However, the biological relevance of the fast conformational dynamics still remains elusive. Exploring the dynamic heterogeneity of biopolymers is proposed as a potential approach to the identification of biologically important dynamics.

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The effects of omega‐3 polyunsaturated fatty acids and genetic variants on methylation levels of the interleukin‐6 gene promoter
Authors: Ma Yiyi , Smith Caren E. , Lai Chao‐Qiang , Irvin Marguerite R. , Parnell Laurence D. , Lee Yu‐Chi , Pham Lucia D. , Aslibekyan Stella , Claas Steven A. , Tsai Michael Y. , Borecki Ingrid B. , Kabagambe Edmond K. , Ordovás José M. , Absher Devin M. , Arnett Donna K.
Published: October 2015

Scope

Omega‐3 PUFAs (n‐3 PUFAs) reduce IL‐6 gene expression, but their effects on transcription regulatory mechanisms are unknown. We aimed to conduct an integrated analysis with both population and in vitro studies to systematically explore the relationships among n‐3 PUFA, DNA methylation, single nucleotide polymorphisms (SNPs), gene expression, and protein concentration of IL6.

Methods and results

Using data in the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN) study and the Encyclopedia of DNA Elements (ENCODE) consortium, we found that higher methylation of IL6 promoter cg01770232 was associated with higher IL‐6 plasma concentration (p = 0.03) and greater IL6 gene expression (p = 0.0005). Higher circulating total n‐3 PUFA was associated with lower cg01770232 methylation (p = 0.007) and lower IL‐6 concentration (p = 0.02). Moreover, an allele of IL6 rs2961298 was associated with higher cg01770232 methylation (p = 2.55 × 10−7). The association between n‐3 PUFA and cg01770232 methylation was dependent on rs2961298 genotype (p = 0.02), but higher total n‐3 PUFA was associated with lower cg01770232 methylation in the heterozygotes (p = 0.04) not in the homozygotes.

Conclusion

Higher n‐3 PUFA is associated with lower methylation at IL6 promoter, which may be modified by IL6 SNPs.
Coffee, tea, caffeine and risk of depression: A systematic review and dose–response meta‐analysis of observational studies
Authors: Grosso Giuseppe , Micek Agnieszka , Castellano Sabrina , Pajak Andzrej , Galvano Fabio
Published: October 2015

Scope

The aim of the study was to systematically review and analyze results from observational studies on coffee, caffeine, and tea consumption and association or risk of depression.

Methods and results

Embase and PubMed databases were searched from inception to June 2015 for observational studies reporting the odds ratios or relative risks (RRs) and 95% confidence intervals (CI) of depression by coffee/tea/caffeine consumption. Random effects models, subgroup analyses, and dose–response analyses were performed. Twelve studies with 23 datasets were included in the meta‐analysis, accounting for a total of 346 913 individuals and 8146 cases of depression. Compared to individuals with lower coffee consumption, those with higher intakes had pooled RR of depression of 0.76 (95% CI: 0.64, 0.91). Dose–response effect suggests a nonlinear J‐shaped relation between coffee consumption and risk of depression with a peak of protective effect for 400 mL/day. A borderline nonsignificant association between tea consumption and risk of depression was found (RR 0.70, 95% CI: 0.48, 1.01), while significant results were found only for analysis of prospective studies regarding caffeine consumption (RR = 0.84, 95% CI: 0.75, 0.93).

Conclusion

This study suggests a protective effect of coffee and, partially, of tea and caffeine on risk of depression.
Differentiating low‐ and high‐grade pediatric brain tumors using a continuous‐time random‐walk diffusion model at high b‐values
Authors: Karaman M. Muge , Sui Yi , Wang He , Magin Richard L. , Li Yuhua , Zhou Xiaohong Joe
Published: October 2015

Purpose

To demonstrate that a continuous‐time random‐walk (CTRW) diffusion model can improve diagnostic accuracy of differentiating low‐ and high‐grade pediatric brain tumors.

Methods

Fifty‐four children with histopathologically confirmed brain tumors underwent diffusion MRI scans at 3Twith 12 b‐values (0‐4000 s/mm2). The diffusion imageswere fit to a simplified CTRW model to extract anomalous diffusion coefficient, Dm, and temporal and spatial heterogeneity parameters, α and β, respectively. Using histopathology results as reference, a k‐means clustering algorithm and a receiver operating characteristic (ROC) analysis were employed to determine the sensitivity, specificity, and diagnostic accuracy of the CTRW parameters in differentiating tumor grades.

Results

Significant differences between the low‐ and high‐grade tumors were observed in the CTRW parameters (p‐values<0.001). The k‐means analysis showed that the combination of three CTRW parameters produced higher diagnostic accuracy (85% vs. 75%) and specificity (83% vs. 54%) than the apparent diffusion coefficient (ADC) from a mono‐exponential model. The ROC analysis revealed that any combination of the CTRW parameters gave a larger area under the curve (0.90‐0.96) than using ADC (0.80).

Conclusion

With its sensitivity to intravoxel heterogeneity, the simplified CTRW model is useful for non‐invasive grading of pediatric brain tumors, particularly when surgical biopsy is not feasible. Magn Reson Med 76:1149–1157, 2016. © 2015 Wiley Periodicals, Inc.
A semiadiabatic spectral‐spatial spectroscopic imaging (SASSI) sequence for improved high‐field MR spectroscopic imaging
Authors: Feldman Rebecca E. , Balchandani Priti
Published: October 2015

Purpose

MR spectroscopic imaging (MRSI) benefits from operation at 7T due to increased signal‐to‐noise ratio (SNR) and spectral separation. The 180° radiofrequency (RF) pulses used in the conventional MRSI sequences are particularly susceptible to the variation in the transmitted RF (B1) field and severe chemical shift localization errors at 7T. RF power deposition, as measured by specific absorption rate (SAR), also increases with field strength. Adiabatic 180° RF pulses may mitigate the effects of B1 variation. We designed and implemented a semiadiabatic spectral‐spatial spectroscopic imaging (SASSI) pulse sequence to provide more uniform spectral data at 7T with reduced SAR.

Methods

The adiabatic Shinnar–Le Roux algorithm was used to generate a high bandwidth 180° adiabatic spectral‐spatial (SPSP) pulse that captured a spectral range containing the main metabolites of interest. A pair of 180° SPSP pulses was used to refocus the signal excited by a 90° SPSP pulse in order to select a 3D volume of interest in the SASSI sequence.

Results

The SASSI pulse sequence produced spectra with more uniform brain metabolite SNR when compared with the conventional nonadiabatic MRSI sequence.

Conclusion

SASSI achieved comparable SNR to the current adiabatic alternative, semi‐LASER, but with 1/3 of the SAR. Magn Reson Med 76:1071–1082, 2016. © 2015 Wiley Periodicals, Inc.
A quantitative study of susceptibility and additional frequency shift of three common materials in MRI
Authors: Xie He , Cheng Yu‐Chung N. , Kokeny Paul , Liu Saifeng , Hsieh Ching‐Yi , Haacke E. Mark , Palihawadana Arachchige Maheshika , Lawes Gavin
Published: October 2015

Purpose

This work quantifies magnetic susceptibilities and additional frequency shifts derived from different samples.

Methods

Twenty samples inside long straws were imaged with a multiecho susceptibility weighted imaging and analyzed with two approaches for comparisons. One approach applied our complex image summation around a spherical or cylindrical object method to phase distributions outside straws. The other approach utilized phase values inside each straw from two orientations. Both methods quantified susceptibilities of each sample at each echo time. The
value of each sample was measured too. Uncertainty of each measurement was also estimated.

Results

Quantified susceptibilities from complex image summation around a spherical or cylindrical object are consistent within uncertainties between different echo times. However, this is not the case for the other method. Nonetheless, most quantified susceptibilities are consistent between these two methods. Phase values due to additional frequency shifts in some of ferritin and nanoparticle samples have been identified. Only
values quantified from low concentration nanoparticle samples agree with the predictions from the static dephasing theory.

Conclusion

This work suggests that using the sample sizes and phase values only outside samples can correctly quantify the susceptibilities of those samples. With the presence of a possible additional frequency shift inside a material, it will not be suitable to obtain susceptibility maps without taking that into account. Magn Reson Med 76:1263–1269, 2016. © 2015 Wiley Periodicals, Inc.
From Consultation to Participation
Authors: Wellens Lore , Jegers Marc
Published: October 2015

Empirical research in the literature on accountability of nonprofit organizations (NPOs) toward their beneficiaries is scarce, and the available studies have a number of limitations. Our study attempts to overcome some of them and focuses on one specific component of accountability toward beneficiaries: beneficiary impact on organizational decision making and output. Data were collected by surveying general managers of 790 Belgian NPOs in fourteen industries. Results show that most NPOs implement some mechanisms to involve beneficiaries and their representatives in organizational policy making, mechanisms that vary between and within industries. Despite the existence of such mechanisms, their perceived association with impact on policy making and associated potential organizational effects is weak, though positive.
Prophylactic use of the Arabin cervical pessary in fetuses with severe congenital diaphragmatic hernia treated by fetoscopic endoluminal tracheal occlusion (FETO): preliminary experience
Authors: Dobrescu Oana , Cannie Mieke M. , Cordier Anne‐Gael , Rodó Carlota , Fabietti Isabella , Benachi Alexandra , Carreras Elena , Persico Nicola , Hurtado Ivan , Gucciardo Léonardo , Jani Jacques C.
Published: October 2015

Objective

The aim of this study was to describe whether the prophylactic use of a cervical pessary decreases the rate of premature birth in congenital diaphragmatic hernia (CDH) fetuses treated with fetoscopic tracheal occlusion (FETO).

Methods

The study concerns a consecutive series of cases with CDH and FETO and a group of CDH without FETO. In a subgroup of the FETO group, a prophylactic cervical pessary was inserted the day following the procedure. Gestational age (GA) at birth was the primary outcome.

Results

Fifty‐nine fetuses with FETO and 47 expectantly managed were included. The last 15 FETO had a cervical pessary inserted. The median GA at delivery in the FETO group with pessary was 35.1 weeks and was not different from that in the FETO group without a pessary (34.3 weeks; p = 0.28) but was below that in the expectantly managed group (38.3 weeks; p < 0.001).

Conclusion

Early results suggest that prophylactic use of an Arabin cervical pessary does not prolong gestation of CDH fetuses treated with FETO. © 2015 John Wiley & Sons, Ltd.
Developing a Cost Overrun Predictive Model for Complex Systems Development Projects
Authors: Adoko Moses T. , Mazzuchi Thomas A. , Sarkani Shahram
Published: October 2015

While system complexity is on the rise across many product lines, the resources required to successfully design and implement complex systems remain constrained. Because financiers of complex systems development efforts actively monitor project implementation cost, project performance models are needed to help project managers predict their cost compliance and avoid cost overruns. This article describes recent research conducted by the authors to develop a cost overrun predictive model using five known drivers of complex systems development cost. The study identifies schedule and reliability, as the key determinants of whether or not a large complex systems development project will experience cost overrun.
The effect of collector gap width on the extent of molecular orientation in polymer nanofibers
Authors: Ma Xiaoqian , Liu Jinglin , Ni Chaoying , Martin David C. , Bruce Chase D. , Rabolt John F.
Published: October 2015

Electrospun poly(vinylidene fluoride) (PVDF) nanofibers were collected on aluminum foil across a gap with widths that varied in size from 2 to 10 mm. Scanning electron microscopy (SEM) images on fiber bundles showed that in all cases, fibers in the gap were macroscopically aligned across the gap. However, single fiber selected area electron diffraction (SAED) patterns and polarized Fourier Transform Infrared (FTIR) spectra demonstrated that fibers deposited across the gap were also highly aligned at the molecular level with the polymer backbones oriented along the fiber axis and that the extent of molecular orientation increased with the gap width. A possible explanation for this observation is based on the repulsion of similarly charged nanofibers and the simultaneous attraction of these fibers to the oppositely charged gap edges. This provides a plausible model for understanding the deposition kinetics and subsequent molecular orientation as a function of gap size when electrospinning using this method of fiber collection. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016, 54, 617–623
Who cooks the books in China, and does it pay? Evidence from private, high‐technology firms
Authors: Stuart Toby , Wang Yanbo
Published: October 2015

Research summary: We document the extent of fraudulent reporting among 467 private Chinese technology companies. Comparing the financial statements concurrently submitted to two different state agencies, we demonstrate a systematic gap in reported profit figures in the two sets of books. We find: (1) more than half the sampled companies report incentive‐compatible, materially discrepant profit numbers to the two agencies; (2) politically connected companies are approximately 18 percent more likely to commit fraud and those with venture capital backing are 19 percent more likely to do so; and (3) it pays to cheat. We estimate that companies who “cook” their books have considerably higher odds of receiving an innovation grant. Especially given its prevalence, we conclude that fraud can be a source of performance differential for emerging market companies.

Managerial summary: We document that more than half of a sample of 467 private, Chinese technology companies engage in fraudulent financial reporting. By comparing the financial statements companies concurrently submitted to two different state agencies, we demonstrate a systematic gap in reported profit figures in the two sets of books. Relative to the companies without these attributes, we find that politically connected companies are approximately 18 percent more likely to commit fraud and those with venture capital backing are 19 percent more likely to do so. Furthermore, we show that it pays to cheat. We estimate that companies who “cook” their books have considerably higher odds of receiving a government‐sponsored innovation grant. Therefore, fraud can be a source of performance differential for emerging market companies. Copyright © 2015 John Wiley & Sons, Ltd.
Performance deviations and acquisition premiums: The impact of CEO celebrity on managerial risk‐taking
Authors: Cho Sam Y. , Arthurs Jonathan D. , Townsend David M. , Miller Douglas R. , Barden Jeffrey Q.
Published: October 2015

Research summary: This article draws on identity control theory and a study of acquisition premiums to explore how CEO celebrity status and financial performance relative to aspirations affect firm risk behavior. The study finds that celebrity CEOs tend to pay smaller premiums for target firms, but these tendencies change when prior firm performance deviates from the industry average returns, thereby leading these CEOs to pay higher premiums. The study also finds that the premiums tend to be even larger when celebrity CEOs have more recently attained celebrity status. Taken together, these findings contribute to identity control theory and CEO celebrity literatures by suggesting that celebrity status is a double‐edged sword and that the internalization of celebrity status by CEOs strongly influences the decision‐making of CEOs.

Managerial summary: The purpose of this article is to examine how CEO celebrity status and financial performance relative to aspirations affect the size of acquisition premiums. The study finds that celebrity CEOs tend to pay smaller premiums for target firms. However, when celebrity CEOs' prior firm performance is either better or worse than the industry average, these CEOs pay higher premiums. This situation is exacerbated when the CEO has only recently been crowned a celebrity. In effect, these CEOs feel great pressure to match the inflated performance expectations that come with celebrity status. These findings suggest that being a celebrity is a double‐edged sword. The implication here is that CEOs who have recently been crowned a celebrity should be aware of these pressures and cope accordingly. Copyright © 2015 John Wiley & Sons, Ltd.
Free‐riding in multi‐party alliances: The role of perceived alliance effectiveness and peers' collaboration in a research consortium
Authors: Fonti Fabio , Maoret Massimo , Whitbred Robert
Published: October 2015

Research summary: Multi‐party alliances rely on partners' willingness to commit and pool their efforts in joint endeavors. However, partners face the dilemma of how much to commit to the alliance. We shed light on this issue by analyzing the relationship between partners' free‐riding—defined as their effort‐withholding—and their perceptions of alliance effectiveness and peers' collaboration. Specifically, we posit a U‐shaped relationship between partners' subjective evaluations of alliance effectiveness and their free‐riding. We also hypothesize a negative relation between partners' perceptions of the collaboration of peer organizations and their free‐riding. Results from a mixed‐method study—combining regression analysis of primary data on a major inter‐organizational research consortium and evidence from two experimental designs—support our hypotheses, bearing implications for the multi‐party alliances literature.

Managerial summary: Free‐riding is a major concern in multi‐party alliances such as large research consortia, since the performance of these governance forms hinges on the joint contribution of multiple partners that often operate according to different logics (e.g., universities, firms, and government agencies). We show that, in such alliances, partners' perceptions have relevant implications for their willingness to contribute to the consortium's shared goals. Specifically, we find that partners free‐ride more—that is, contribute less—when they perceive the effectiveness of the overall alliance to be either very low or very high. Partners also gauge their commitment to the alliance on the perception of the effort of their peers—that is, other organizations similar to them. These findings provide managers of multi‐party alliances with additional levers to motivate partners to contribute fairly to such joint endeavor. Copyright © 2015 John Wiley & Sons, Ltd.
Identifying the critical components for a conceptual understanding of the mole in secondary science classrooms
Authors: Fang Su‐Chi , Hart Christina , Clarke David
Published: October 2015

The amount of substance and its unit the mole is a basic concept in chemistry. However, previous research has shown that teaching and learning the concept are challenging tasks for both teachers and students. The purpose of this study was to pinpoint the problems which emerge in the teaching and learning process, and provide integrated suggestions for classroom instruction. By means of videotaping and interviews, the case studies explored how the mole is presented and conceptualized in two secondary classrooms in two different countries, Australia and Taiwan. Data analysis was based on a concept map and focused on how two key ideas were presented in the lessons and perceived by the students: (1) the definition of the mole, and (2) the concept of molar mass. The findings show that during the lessons on the mole, most of the time was spent on solving stoichiometric problems. Conceptually, the number aspect of the mole, that is, Avogadro's number, was emphasized; the concept of molar mass was introduced without meaningfully connecting it to the concept of relative atomic/molecular mass. Although the students were able to solve relevant problems, they could not coherently explain the relations among the concepts. Two critical components for a conceptual understanding of the mole emerged: (1) the number aspect of the mole needs to be justified by its mass aspect, and (2) the connection between molar mass and relative atomic/molecular mass needs to be explicitly explained. The two components provide one explanation for students' algorithmic learning and their confusion in learning about the mole, and serve as concrete suggestions for improving classroom instruction. The study once again manifested the significance of teaching for conceptual understanding in science education. It also exemplifies how a concept map of a specific scientific concept can also be a useful analytical tool in educational research. © 2015 Wiley Periodicals, Inc. J Res Sci Teach 53: 181–214, 2016.
British Decolonization, 1946–1997
Authors: Mcinryre W. David
Published: October 2015

The sudden demise of arguably the world's greatest empire in the years following the Second World War was a momentous event in global history. After nearly four centuries of colonial activity, the British relinquished their empire in a little more than twenty years.

In this comprehensive new survey, David McIntyre narrates the sequence of decolonisation, summarises the historical controversies surrounding its causes, and considers what was distinctive about the way events unfolded. The author argues that although colonial self-government had a long pedigree going back to the American colonies (and Dominion status had become a peaceful evolutionary route to independence), the upsurge of colonial nationalisms after 1945 meant that policy-makers were overtaken by events. The great speed at which the numerous dependencies in Asia, Africa, the Caribbean and Pacific were relinquished is analysed and the Commonwealth since decolonisation reconsidered, revealing an association displaying surprising vigour in its post-Britannic years.
Does hysteroscopic metroplasty for septate uterus represent a risk factor for adverse outcome during pregnancy and labor?
Authors: Kenda Šuster Nataša , Gergolet Marco
Published: October 2015

The aim of the study was to evaluate whether hysteroscopic metroplasty for septate uterus represents a risk factor of adverse outcome in pregnancy, during labor, and after delivery. This is a retrospective comparative study of obstetric complications of 99 patients who underwent hysteroscopic metroplasty in a 5-year period (study group) and 4155 women, who gave birth in the same hospital in the same period (control group). No difference in obstetric outcome (preterm labor, hemorrhage before and after delivery, mean weeks of gestation at delivery, mean birth weight, breech presentation, and cesarean section rate) between the two groups has been found. The results of this study suggest that patients who underwent hysteroscopic metroplasty for septate uterus are at no higher risk of adverse obstetric outcome at term and during labor, comparing to the general population. Though vaginal delivery seems to be safe, rare but serious complication, reported by several studies, like uterine rupture during pregnancy or labor, should always be taken into consideration.
Propofol target‐controlled infusion for sedated gastrointestinal endoscopy: A comparison of propofol alone versus propofol–fentanyl–midazolam
Authors: Hsu Chiung‐Dan , Huang Jui‐Mei , Chuang Ya‐Ping , Wei Hua‐Yi , Su Yu‐Chung , Wu Jeng‐Yih , Wang Wen‐Ming , Hsu Hung‐Te , Huang Hui‐Fang , Lu I‐Cheng , Lu David Vi
Published: October 2015

Gastrointestinal (GI) endoscopy is the major technique for diagnosis of GI disease and treatment. Various sedation and analgesia regimens such as midazolam, fentanyl, and propofol can be used during GI endoscopy. The purpose of the study was to compare propofol alone and propofol combination with midazolam and fentanyl in moderate sedation for GI endoscopy. One hundred patients undergoing GI endoscopy were enrolled in this study. All patients received a propofol target‐controlled infusion (TCI) to maintain sedation during the procedure. Patients were randomly allocated into either Group P (propofol TCI alone) or Group C (combination of propofol TCI plus midazolam and fentanyl). Dermographic data, anesthetic parameters (sedation regimen, blood pressure, heart rate, and oxygen saturation), procedure parameters (procedure time, colonoscopy, or panendoscopy), propofol consumption, and adverse events (hypoxia, hypotension, and bradycardia) were all recorded. Postprocedural records included recovery time, postoperative adverse events (nausea, vomiting, dizziness, recall, and pain) and satisfaction. The average propofol consumption was 251 ± 83 mg in Group P and 159 ± 73 mg in Group C (p < 0.001). The incidence of transient hypotension was higher in Group P (p = 0.009). The recovery time and discharge time were both shorter in Group C (p < 0.001 and p = 0.006 respectively). Overall, postprocedural adverse events were similar in both groups. The postanesthetic satisfaction was comparable in both groups. TCI of propofol combined with midazolam and fentanyl achieved sedation with fewer hypotension episodes and shorter recovery and discharge time than propofol TCI alone in patients undergoing GI endoscopy.
Laparoscopic adrenalectomy for large adrenal masses: Is it really more complicated?
Authors: Bozkurt Ibrahim Halil , Arslan Murat , Yonguc Tarik , Degirmenci Tansu , Koras Omer , Gunlusoy Bulent , Minareci Suleyman
Published: October 2015

Laparoscopic treatment of large adrenal tumors is still questionable due to concern over the risk of malignancy as well as the technical difficulties. No exact dimensional cut‐off has been described for laparoscopic adrenalectomy (LA). In this study, we reviewed our experience with LA for masses ≥ 8 cm and tried to determine the limitations of this surgery in this group of patients. Sixteen patients with adrenal mass ≥ 8 cm (Group 1) and 19 patients with adrenal mass < 8 cm (Group 2) treated with transabdominal LA were included in this study. We analyzed operative time, intraoperative and postoperative complications and length of postoperative hospital stay with respect to tumor size and clinopathologic features. Mean maximum tumor diameters were 91.7 mm (range, 80–150 mm) and 52.4 mm (range, 35–73 mm) in Group 1 and Group 2, respectively. Operation time and blood loss were higher in Group 1 compared to Group 2, but these differences did not reach significant levels (p > 0.05). Conversion to an open procedure required in two patients, one from each group, because of the firm attachments of adrenal mass to the surrounding tissue. In conclusion, our study demonstrated that LA is a safe and feasible procedure for large lesions even up to 15 cm. The risk of finding incidental adrenal cortical cancer was significantly increased for large lesions in our series as in the literature; therefore, it is important to follow the strict oncological principles in these cases.
Earth's Climate Cycles Might Have an Eccentric Explanation
Authors: Betz Eric
Published: October 2015

Mid-ocean ridge eruptions follow the cycles of tides and Earth's orbital eccentricity, indicating a possible role in long-term climate shifts.
Targets of Biggest Global Carbon Emitters Flunk Fairness Test
Authors: Sullivan Cody
Published: October 2015

Pledges so far by the United States, European Union, and China would require all other countries to emit 7 to 14 times less per capita than those three regions by 2030 to limit warming to 2°C.
The Curious Case of the Halloween Ghost Electrons
Authors: Zastrow Mark
Published: October 2015

When solar storms pounded Earth during Halloween in 2003, scientists were eager to measure their effects. But new research shows one satellite was seeing "ghost" particles that probably weren't real.