bluuebunny/crossref_metadata_2025 huggingface dataset:
Structural, vibrational, and quasiparticle band structure of 1,1-diamino-2,2-dinitroethelene from ab initio calculations
Authors: Appalakondaiah S. , Vaitheeswaran G. , Lebègue S.
Published: January 2014

The effects of pressure on the structural and vibrational properties of the layered molecular crystal 1,1-diamino-2,2-dinitroethelene (FOX-7) are explored by first principles calculations. We observe significant changes in the calculated structural properties with different corrections for treating van der Waals interactions to Density Functional Theory (DFT), as compared with standard DFT functionals. In particular, the calculated ground state lattice parameters, volume and bulk modulus obtained with Grimme's scheme, are found to agree well with experiments. The calculated vibrational frequencies demonstrate the dependence of the intra and inter-molecular interactions on FOX-7 under pressure. In addition, we also found a significant increment in the N–H...O hydrogen bond strength under compression. This is explained by the change in bond lengths between nitrogen, hydrogen, and oxygen atoms, as well as calculated IR spectra under pressure. Finally, the computed band gap is about 2.3 eV with generalized gradient approximation, and is enhanced to 5.1 eV with the GW approximation, which reveals the importance of performing quasiparticle calculations in high energy density materials.
Comment on “Motion of a helical vortex filament in superfluid 4He under the extrinsic form of the local induction approximation” [Phys. Fluids 25, 085101 (2013)]
Authors: Hietala Niklas , Hänninen Risto
Published: January 2014

We comment on the paper by Van Gorder [“Motion of a helical vortex filament in superfluid 4He under the extrinsic form of the local induction approximation,” Phys. Fluids 25, 085101 (2013)]. We point out that the flow of the normal fluid component parallel to the vortex will often lead into the Donnelly–Glaberson instability, which will cause the amplification of the Kelvin wave. We explain why the comparison to local nonlinear equation is unreasonable, and remark that neglecting the motion in the x-direction is not reasonable for a Kelvin wave with an arbitrary wavelength and amplitude. The correct equations in the general case are also derived.
Simulation of a small molecule analogue of a lithium ionomer in an external electric field
Authors: Waters Sara M. , McCoy John D. , Frischknecht Amalie L. , Brown Jonathan R.
Published: January 2014

We have investigated the ion dynamics in lithium-neutralized 2-pentylheptanoic acid, a small molecule analogue of a precise poly(ethylene-co-acrylic acid) lithium ionomer. Atomistic molecular dynamics simulations were performed in an external electric field. The electric field causes alignment of the ionic aggregates along the field direction. The energetic response of the system to an imposed oscillating electric field for a wide range of frequencies was tracked by monitoring the coulombic contribution to the energy. The susceptibility found in this manner is a component of the dielectric susceptibility typically measured experimentally. A dynamic transition is found and the frequency associated with this transition varies with temperature in an Arrhenius manner. The transition is observed to be associated with rearrangements of the ionic aggregates.
Magnetocaloric effect of Co62Nb6Zr2B30 amorphous alloys obtained by mechanical alloying or rapid quenching
Authors: Moreno L. M. , Blázquez J. S. , Ipus J. J. , Borrego J. M. , Franco V. , Conde A.
Published: January 2014

Amorphous samples of nominal composition Co62Nb6Zr2B30 have been prepared using mechanical alloying (MA) and rapid quenching (RQ) techniques. Differences appear in Curie temperature and the phases developed after crystallization. Refrigerant capacity is enhanced 20% in the MA-sample with respect to that of RQ-sample. Neglecting the demagnetizing factor of powder samples significantly affects the exponent n characterizing the field dependence of the maximum magnetic entropy change.
Communication: The origin of rotational enhancement effect for the reaction of H2O+ + H2 (D2)
Authors: Li Anyang , Li Yongle , Guo Hua , Lau Kai-Chung , Xu Yuntao , Xiong Bo , Chang Yih-Chung , Ng C. Y.
Published: January 2014

We have measured the absolute integral cross sections (σ’s) for H3O+ formed by the reaction of rovibrationally selected H2O+(X2B1; v1+v2+v3+ = 000; N+Ka+Kc+ = 000, 111, and 211) ion with H2 at the center-of-mass collision energy (Ecm) range of 0.03–10.00 eV. The σ(000), σ(111), and σ(211) values thus obtained reveal rotational enhancements at low Ecm < 0.50 eV, in agreement with the observation of the previous study of the H2O+(X2B1) + D2 reaction. This Communication presents important progress concerning the high-level ab initio quantum calculation of the potential energy surface for the H2O+(X2B1) + H2 (D2) reactions, which has provided valuable insight into the origin of the rotational enhancement effect. Governed by the charge and dipole-induced-multipole interactions, the calculation shows that H2 (D2) approaches the H end of H2O+(X2B1) in the long range, whereas chemical force in the short range favors the orientation of H2 (D2) toward the O side of H2O+. The reorientation of H2O+ reactant ion facilitated by rotational excitation thus promotes the H2O+ + H2 (D2) reaction along the minimum energy pathway, rendering the observed rotational enhancement effects. The occurrence of this effect at low Ecm indicates that the long range charge and dipole-induced-multipole interactions of the colliding pair play a significant role in the dynamics of the exothermic H2O+ + H2 (D2) reactions.
Polar nanoregions and dielectric properties in high-strain lead-free 0.93(Bi1/2Na1/2)TiO3-0.07BaTiO3 piezoelectric single crystals
Authors: Chen Cheng-Sao , Chen Pin-Yi , Tu Chi-Shun
Published: January 2014

A structural coexistence of rhombohedral (R) and tetragonal (T) phases has been revealed in the (001)c-cut lead-free 0.93(Bi1/2Na1/2)TiO3–0.07BaTiO3 (BNB7T) piezoelectric crystals, which grown by the self-flux method, in the lower temperatures by high-resolution synchrotron X-ray diffraction, reciprocal space mapping, and transmission electron microscopy. The dielectric permittivity exhibits a thermal hysteresis in the region of 120–260 °C, implying a first-order-like phase transition from R+T to T. The real part (ε′) of dielectric permittivity begins to deviates from the Curie-Weiss equation, ε′ = C/(T − To), from the Burns temperature TB = 460 °C, below which the polar nanoregions (or nanoclusters) develop and attenuate dielectric responses. The polar nanoregions of 5–10 nm were revealed by high-resolution transmission electron microscope. The normal piezoelectric coefficient d33 exhibits a rapid increase at E = 15–20 kV/cm and reaches a maximum of d33 ∼450 pC/N. The high piezoelectric response and E-field induced strain in BNB7T single crystals can be attributed to structural phase transitions under an E-field application.
Degradation characteristics of metal/Al2O3/n-InGaAs capacitors
Authors: Palumbo F. , Eizenberg M.
Published: January 2014

Implementation of new materials in Metal-Oxide-Semiconductor stacks requires capabilities to predict long-time degradation as well as the impact of process changes on degradation processes. In this work, the degradation under constant voltage stress of metal gate/Al2O3/InGaAs stacks is studied for different pre-dielectric deposition treatments. The results show that the degradation, particularly under negative bias, is strongly affected by the oxide-semiconductor surface treatment of the samples. Two contributions (interface states and bulk traps) dominate depending on the stress conditions. Surface treatment with NH4OH shows a better quality of the interface in term of interface states; however, it contributes to generation of positive charge on the dielectric layer.
The importance of holes in aluminium tris-8-hydroxyquinoline (Alq3) devices with Fe and NiFe contacts
Authors: Zhang Hongtao , Desai P. , Zhan Y. Q. , Drew A. J. , Gillin W. P. , Kreouzis T.
Published: January 2014

To study the dominant charge carrier polarity in aluminium tris-8-hydroxyquinoline (Alq3) based spin valves, single Alq3 layer devices with NiFe, ITO, Fe, and aluminium electrodes were fabricated and characterised by Time of Flight (ToF) and Dark Injection (DI) techniques, yielding a lower hole mobility compared to electron mobility. We compare the mobility measured by DI for the dominant carrier injected from NiFe and Fe electrodes into Alq3, to that of holes measured by ToF. This comparison leads us to conclude that the dominant charge carriers in Alq3 based spin valves with NiFe or Fe electrodes are holes.
Effect of superconducting spacer layer thickness on magneto-transport and magnetic properties of La0.7Sr0.3MnO3/YBa2Cu3O7/La0.7Sr0.3MnO3 heterostructures
Authors: Sharma Minaxi , Pandey Pankaj K. , Sharma K. K. , Kumar Ravi , Choudhary R. J. , Venkateshwarlu D. , Ganesan V.
Published: January 2014

We have studied the magneto-transport and magnetic properties of LSMO/YBCO/LSMO trilayers on LaAlO3 (001) substrate, deposited using pulsed laser deposition technique. From x-ray diffraction measurements, it is confirmed that the grown trilayer films are single phase natured. The temperature dependent resistivity shows a metallic behavior below 350 K. At low temperature from resistivity fitted data, we observe that electron-electron, electron-phonon, and electron-magnon interactions are the main factors for scattering of carriers. The ferromagnetic LSMO layers suppress the critical temperature of YBCO spacer layer. We observe maximum magnetoresistance value ∼49% at 250 K for LSMO(200 nm)/YBCO(50 nm)/LSMO(200 nm) trilayer. Magnetization measurements reveal that at room temperature the YBCO spacer layer is allowing the LSMO layers to interact antiferromagnetically.
Density functional theory study of the mechanism of Li diffusion in rutile RuO2
Authors: Jung Jongboo , Cho Maenghyo , Zhou Min
Published: January 2014

First-principle calculations are carried out to study the diffusion of Li ions in rutile structure RuO2, a material for positive electrodes in rechargeable Li ion batteries. The calculations focus on migration pathways and energy barriers for diffusion in Li-poor and Li-rich phases using the Nudged Elastic Band Method. Diffusion coefficients estimated based on calculated energy barriers are in good agreement with experimental values reported in the literature. The results confirm the anisotropic nature of diffusion of Li ions in one-dimensional c channels along the [001] crystalline direction of rutile RuO2 and show that Li diffusion in the Li-poor phase is faster than in the Li-rich phase. The findings of fast Li diffusion and feasible Li insertion at low temperatures in the host rutile RuO2 suggest this material is a good ionic conductor for Li transport. The finding also suggests possible means for enhancing the performance of RuO2-based electrode materials.
Isolation and Structure of a Hydrogen-bonded 2,2′:6′,2′′-Terpyridin-4′-one Acetic Acid Adduct
Authors: Florio Pas , Coghlan Campbell J. , Lin Chih-Pei , Saito Kei , Campi Eva M. , Jackson W. Roy , Hearn Milton T. W.
Published: January 2014

Herein, we report the crystal structure of a key intermediate in the synthesis of 4′-substituted-terpyridines. Our findings confirm that the terpyridin-4′-one intermediate as generated from the condensation reaction of the corresponding triketone precursor with ammonium acetate is isolated as a hydrogen-bonded adduct with acetic acid, and not, as previously reported, as the acetate salt of a protonated pyridine nitrogen. This finding provides a rationale for the behaviour and structure of substituted terpyridin-4′-ones and pyridones in both the solid state and in solution.
Long noncoding RNA-mediated intrachromosomal interactions promote imprinting at the Kcnq1 locus
Authors: Zhang He , Zeitz Michael J. , Wang Hong , Niu Beibei , Ge Shengfang , Li Wei , Cui Jiuwei , Wang Guanjun , Qian Guanxiang , Higgins Michael J. , Fan Xianqun , Hoffman Andrew R. , Hu Ji-Fan
Published: January 2014

Kcnq1ot1 is a long noncoding ribonucleic acid (RNA; lncRNA) that participates in the regulation of genes within the Kcnq1 imprinting domain. Using a novel RNA-guided chromatin conformation capture method, we demonstrate that the 5′ region of Kcnq1ot1 RNA orchestrates a long-range intrachromosomal loop between KvDMR1 and the Kcnq1 promoter that is required for maintenance of imprinting. PRC2 (polycomb repressive complex 2), which participates in the allelic repression of Kcnq1, is also recruited by Kcnq1ot1 RNA via EZH2. Targeted suppression of Kcnq1ot1 lncRNA prevents the creation of this long-range intrachromosomal loop and causes loss of Kcnq1 imprinting. These observations delineate a novel mechanism by which an lncRNA directly builds an intrachromosomal interaction complex to establish allele-specific transcriptional gene silencing over a large chromosomal domain.
Adaptor proteins involved in polarized sorting
Authors: Bonifacino Juan S.
Published: January 2014

Polarized cells such as epithelial cells and neurons exhibit different plasma membrane domains with distinct protein compositions. Recent studies have shown that sorting of transmembrane proteins to the basolateral domain of epithelial cells and the somatodendritic domain of neurons is mediated by recognition of signals in the cytosolic domains of the proteins by adaptors. These adaptors are components of protein coats associated with the trans-Golgi network and/or recycling endosomes. The clathrin-associated adaptor protein 1 (AP-1) complex plays a preeminent role in this process, although other adaptors and coat proteins, such as AP-4, ARH, Numb, exomer, and retromer, have also been implicated.
On the category of cofinite modules which is Abelian
Authors: Bahmanpour Kamal , Naghipour Reza , Sedghi Monireh
Published: January 2014

Let

R
R

denote a commutative Noetherian (not necessarily local) ring and

I
I

an ideal of

R
R

of dimension one. The main purpose of this paper is to generalize, and to provide a short proof of, K. I. Kawasaki’s theorem that the category

M

(
R
,
I

)

c
o
f

\mathscr {M}(R, I)_{cof}

of

I
I

-cofinite modules over a commutative Noetherian local ring

R
R

forms an Abelian subcategory of the category of all

R
R

-modules. Consequently, this assertion answers affirmatively the question raised by R. Hartshorne in his article Affine duality and cofiniteness [Invent. Math. 9 (1970), 145-164] for an ideal of dimension one in a commutative Noetherian ring

R
R

.
The multifork Escherichia coli chromosome is a self-duplicating and self-segregating thermodynamic ring polymer
Authors: Youngren Brenda , Nielsen Henrik Jörk , Jun Suckjoon , Austin Stuart
Published: January 2014

At all but the slowest growth rates, Escherichia coli cell cycles overlap, and its nucleoid is segregated to daughter cells as a forked DNA circle with replication ongoing—a state fundamentally different from eukaryotes. We have solved the chromosome organization, structural dynamics, and segregation of this constantly replicating chromosome. It is locally condensed to form a branched donut, compressed so that the least replicated DNA spans the cell center and the newest DNA extends toward the cell poles. Three narrow zones at the cell center and quarters contain both the replication forks and nascent DNA and serve to segregate the duplicated chromosomal information as it flows outward. The overall pattern is smoothly self-replicating, except when the duplicated terminus region is released from the septum and recoils to the center of a sister nucleoid. In circular cross-section of the cell, the left and right arms of the chromosome form separate, parallel structures that lie in each cell half along the radial cell axis. In contrast, replication forks and origin and terminus regions are found mostly at the center of the cross section, balanced by the parallel chromosome arms. The structure is consistent with the model in which the nucleoid is a constrained ring polymer that develops by spontaneous thermodynamics. The ring polymer pattern extrapolates to higher growth rates and also provides a structural basis for the form of the chromosome during very slow growth.
Kinetics of promoter Pol II on Hsp70 reveal stable pausing and key insights into its regulation
Authors: Buckley Martin S. , Kwak Hojoong , Zipfel Warren R. , Lis John T.
Published: January 2014

The kinetics with which promoter-proximal paused RNA polymerase II (Pol II) undergoes premature termination versus productive elongation is central to understanding underlying mechanisms of metazoan transcription regulation. To assess the fate of Pol II quantitatively, we tracked photoactivatable GFP-tagged Pol II at uninduced Hsp70 on polytene chromosomes and showed that Pol II is stably paused with a half-life of 5 min. Biochemical analysis of short nascent RNA from Hsp70 reveals that this half-life is determined by two comparable rates of productive elongation and premature termination of paused Pol II. Importantly, heat shock dramatically increases elongating Pol II without decreasing termination, indicating that regulation acts at the step of paused Pol II entry to productive elongation.
LGBT Neighbourhoods and ‘New Mobilities’: Towards Understanding Transformations in Sexual and Gendered Urban Landscapes
Authors: Nash Catherine J. , Gorman‐Murray Andrew
Published: January 2014

In this article we apply insights from ‘new mobilities’ approaches to understand the shifting sexual and gendered landscapes of major cities in the global North. The empirical context is the purported ‘demise’ of traditional gay villages in Toronto, Canada and Sydney, Australia, and the emergence of ‘LGBT neighbourhoods’ elsewhere in the inner city. We reinterpret the historical geography of twentieth century LGBT lives and the associated ‘rise and fall’ of gay enclaves through the lens of the ‘politics of mobility’. In this reading, it is apparent that multifaceted movements — migration, physical and social mobility, and motility — underpin the formation of gay enclaves and recent transformations in sexual and gendered landscapes. After the second world war, LGBT communities in the global North were embedded in specific historical geographies of mobility and we trace these in the Canadian and Australian contexts. The ‘great gay migration’ from the 1960s to the 1980s has been joined by new LGBT constellations of mobility in the 2000s, and these have imprinted upon the sexual and gendered landscapes of Toronto and Sydney.
Hip‐hop Urbanism Old and New
Authors: Jeffries Michael P.
Published: January 2014

The sustained connection between hip‐hop and urban identity stems in part from the origins of hip‐hop culture in post‐industrial American cities during the late twentieth century. But hip‐hop urbanism cannot be reduced to nostalgia or respect for previous traditions, as changing spatial demographics and the evolution of hip‐hop production and consumption force a disaggregation and reconsideration of ‘urban music’. Contemporary hip‐hop research in the United States must focus not only on the black and Latino communities responsible for hip‐hop's genesis, but on modern‐day race‐ and class‐based power dynamics, as well as on communities and social networks that are not typically considered urban. Ethnographers are especially well‐positioned to lead this field, thanks to methodological and theoretical tools that allow them to focus on smaller and emergent musical communities in flux.
Maternal adverse effects with different loading infusion rates of antenatal magnesium sulphate for preterm fetal neuroprotection: the IRIS randomised trial
Authors: Bain ES , Middleton PF , Yelland LN , Ashwood PJ , Crowther CA
Published: January 2014

Objective

To evaluate a slower (compared with a standard) infusion rate of the loading dose of magnesium sulphate for preterm fetal neuroprotection as a strategy to reduce maternal adverse effects.

Design

Randomised controlled trial.

Setting

South Australian maternity hospital.

Population

Fifty‐one women at <30 weeks of gestation, where birth was planned or expected within 24 hours.

Methods

Women received a loading infusion of 4 g of magnesium sulphate over either 60 or 20 minutes (followed by maintenance of 1 g/hour until birth, or for up to 24 hours).

Main outcome measures

Any maternal adverse effects associated with the infusion.

Results

Overall, 71% of women experienced adverse effects during the first hour of their infusion; the difference between groups was not significant [15/25 (60%) 60‐minute loading; 21/26 (81%) 20‐minute loading; risk ratio (RR) 0.74; 95% confidence interval (95% CI) 0.51–1.08]. Although no serious maternal complications occurred, adverse effects led to three women ceasing the loading treatment (1/25 in the 60‐minute loading group; 2/26 in the 20‐minute loading group; RR 0.52; 95% CI 0.05–5.38). Women in the 60‐minute loading group experienced significantly less warmth and flushing at 20 minutes into the infusion (7/25 in the 60‐minute loading group; 15/26 in the 20‐minute loading group; RR 0.49; 95% CI 0.24–0.99). No other differences between groups for maternally reported and clinical adverse effects were shown.

Conclusions

A slower rate of administering the loading dose of magnesium sulphate did not reduce the occurrence of maternal adverse effects overall. Flushing and warmth at 20 minutes into the infusion was reduced with a slower infusion.
“No Other Choice”: Reasons for Emergency Department Utilization Among Urban Adults With Acute Asthma
Authors: Lawson Charlotte C. , Carroll Kate , Gonzalez Rodalyn , Priolo Chantel , Apter Andrea J. , Rhodes Karin V.
Published: January 2014

Objectives

Asthma is considered “ambulatory care–sensitive,” yet emergency department (ED) visits remain common. Few studies have examined how ED asthma patients choose their sites of urgent care. The authors explored reasons for asthma‐related ED use among adults.

Methods

From May to September 2012, semistructured qualitative interviews were conducted with a convenience sample of patients visiting a high‐volume urban ED for asthma. A piloted interview guide was used; it had open‐ended questions derived from clinical experience and a focus group of asthmatic adults who frequently use the ED for care. Interviews were conducted until theme saturation was reached. Interview transcripts and field notes were entered into NVivo 10 and double‐coded, using an iterative process to identify patterns of responses, ensure reliability, examine discrepancies, and achieve consensus through content analysis.

Results

Patients view their asthma symptoms in two categories: those they can manage at home and those requiring a provider's attention. Preferred site of acute asthma care varied, but most patients felt that they had little choice for acute exacerbations. Specific reasons for ED visits included wait times, acuity, insurance status, ED resources/expertise, lack of symptom improvement, lack of asthma medication, inability to access outpatient provider, referral by outpatient provider, and referral by friend or family member.

Conclusions

Barriers to urgent outpatient care may contribute to ED use for asthma. Additionally, patients with asthma exacerbations may not recognize a need for provider attention until the need is urgent. Efforts to identify patients with acute asthma early and to increase access to urgent outpatient care may reduce asthma‐related ED visits.
Accuracy of Prehospital Transport Time Estimation
Authors: Wallace David J. , Kahn Jeremy M. , Angus Derek C. , Martin‐Gill Christian , Callaway Clifton W. , Rea Thomas D. , Chhatwal Jagpreet , Kurland Kristen , Seymour Christopher W.
Published: January 2014

Objectives

Estimates of prehospital transport times are an important part of emergency care system research and planning; however, the accuracy of these estimates is unknown. The authors examined the accuracy of three estimation methods against observed transport times in a large cohort of prehospital patient transports.

Methods

This was a validation study using prehospital records in King County, Washington, and southwestern Pennsylvania from 2002 to 2006 and 2005 to 2011, respectively. Transport time estimates were generated using three methods: linear arc distance, Google Maps, and ArcGIS Network Analyst. Estimation error, defined as the absolute difference between observed and estimated transport time, was assessed, as well as the proportion of estimated times that were within specified error thresholds. Based on the primary results, a regression estimate was used that incorporated population density, time of day, and season to assess improved accuracy. Finally, hospital catchment areas were compared using each method with a fixed drive time.

Results

The authors analyzed 29,935 prehospital transports to 44 hospitals. The mean (± standard deviation [±SD]) absolute error was 4.8 (±7.3) minutes using linear arc, 3.5 (±5.4) minutes using Google Maps, and 4.4 (±5.7) minutes using ArcGIS. All pairwise comparisons were statistically significant (p < 0.01). Estimation accuracy was lower for each method among transports more than 20 minutes (mean [±SD] absolute error was 12.7 [±11.7] minutes for linear arc, 9.8 [±10.5] minutes for Google Maps, and 11.6 [±10.9] minutes for ArcGIS). Estimates were within 5 minutes of observed transport time for 79% of linear arc estimates, 86.6% of Google Maps estimates, and 81.3% of ArcGIS estimates. The regression‐based approach did not substantially improve estimation. There were large differences in hospital catchment areas estimated by each method.

Conclusions

Route‐based transport time estimates demonstrate moderate accuracy. These methods can be valuable for informing a host of decisions related to the system organization and patient access to emergency medical care; however, they should be employed with sensitivity to their limitations.
Seasonal flight patterns of Ips typographus in southern Sweden and thermal sums required for emergence
Authors: Öhrn Petter , Långström Bo , Lindelöw Åke , Björklund Niklas
Published: January 2014

The spruce bark beetle Ips typographus is the major tree‐killing bark beetle in Eurasia. To increase knowledge about its seasonal flight patterns and about the thermal sums required for emergence, a study was conducted in southern Sweden from 2006 to 2010.

Seasonal flight patterns were recorded by pheromone traps and development was recorded by felling trees three times during each season.

Flight began, on average, on 27 April [after 47 degree‐days (dd) > 5 °C]. More than 50% of flight activity occurred after mid‐June, and this continued to mid‐August.

Re‐emergence of parental beetles after they had produced the first brood started, on average, on 24 May (after 122 dd). Continued flight and oviposition demonstrated that sister broods were frequent. A higher proportion of parental beetles re‐emerged from trees colonized in May (95%) than in July (20%). Beetles that colonized trees late had to accumulate a higher thermal sum before re‐emerging (400 dd).

Filial beetles began to emerge, on average, on 29 June (after 437 dd) and started to fly in early July, giving rise to at least a partial second generation in each year. A higher proportion of filial beetles had emerged from trees colonized in May (75%) than in July (15%).

Knowledge of these region‐specific flight patterns and the associated thermal sums required for emergence will facilitate efficient pest management by enabling timely removal of fallen and standing weakened host trees. The obtained data will also be useful for improving models that predict the population dynamics in a warmer climate.
Systematic review with meta‐analysis: the proportion of chronic hepatitis B patients with normal alanine transaminase ≤40 IU/L and significant hepatic fibrosis
Authors: Chao D. T. , Lim J. K. , Ayoub W. S. , Nguyen L. H. , Nguyen M. H.
Published: January 2014

Background

Chronic hepatitis B (CHB) may lead to cirrhosis, hepatocellular carcinoma and premature death. Elevated alanine transaminase (ALT) levels ≥ the upper limit of normal (ULN) are a major determinant for initiating anti‐viral therapy; however, ALT levels alone may not be predictive of hepatic fibrosis.

Aim

To determine the proportion of CHB patients with ALT ≤40 IU/L and liver fibrosis stage ≥2. Secondary goals include subgroup analysis by hepatitis B e antigen (HBeAg) status, high hepatitis B virus (HBV) DNA levels, Asian ethnicity, lower ULN of ≤30 IU/L (males) and 19 IU/L (females), and advanced age.

Methods

Studies identified in EMBASE and MEDLINE (1/1990–6/2012) using the search criteria: “Hepatitis B”[Mesh] OR “Hepatitis B virus”[Mesh] OR “Hepatitis B, Chronic”[Mesh])) AND “Alanine Transaminase”[Mesh]) and abstracts containing the term ‘hepatitis’ from recent major U.S. gastroenterology and liver society meetings were considered.

Results

Among nine studies (N = 830 patients), a significant proportion (20.7%; 95% CI: 16.2–26.0%) of CHB patients with ALT levels ≤40 IU/L had significant fibrosis irrespective of HBeAg status, high HBV DNA levels, ethnicity or age, although this proportion may be higher in patients older than 30–40 years old. The corresponding proportion was 27.8% even when the newer ULN of 30 IU/L (males) and 19 IU/L (females) was applied.

Conclusions

Approximately one fifth of CHB patients with ALT ≤40 IU/L may have significant hepatic fibrosis. The approach to such patients should be individualised, as further evaluation and treatment may be appropriate.
Refractory coeliac disease in a country with a high prevalence of clinically‐diagnosed coeliac disease
Authors: Ilus T. , Kaukinen K. , Virta L. J. , Huhtala H. , Mäki M. , Kurppa K. , Heikkinen M. , Heikura M. , Hirsi E. , Jantunen K. , Moilanen V. , Nielsen C. , Puhto M. , Pölkki H. , Vihriälä I. , Collin P.
Published: January 2014

Background

Refractory coeliac disease (RCD) is thought to be a rare disorder, but the accurate prevalence is unknown.

Aim

We aimed to identify the prevalence of and the risk factors for developing RCD in a Finnish population where the clinical detection rate of coeliac disease is high.

Methods

The study involved 11 hospital districts in Finland where the number of treated RCD patients (n = 44), clinically diagnosed coeliac disease patients (n = 12 243) and adult inhabitants (n = 1.7 million) was known. Clinical characteristics at diagnosis of coeliac disease between the RCD patients and patients with uncomplicated disease were compared.

Results

The prevalence of RCD was 0.31% among diagnosed coeliac disease patients and 0.002% in the general population. Of the enrolled 44 RCD patients, 68% had type I and 23% type II; in 9% the type was undetermined. Comparing 886 patients with uncomplicated coeliac disease with these 44 patients that developed RCD later in life, the latter were significantly older (median 56 vs 44 years, P < 0.001), more often males (41% vs. 24%, P = 0.012) and seronegative (30% vs. 5%, P < 0.001) at the diagnosis of coeliac disease. Patients with evolving RCD had more severe symptoms at the diagnosis of coeliac disease, including weight loss in 36% (vs. 16%, P = 0.001) and diarrhoea in 54% (vs. 38%, P = 0.050).

Conclusions

Refractory coeliac disease is very rare in the general population. Patients of male gender, older age, severe symptoms or seronegativity at the diagnosis of coeliac disease are at risk of future refractory coeliac disease and should be followed up carefully.
Tolerogenic dendritic cells produced by lentiviral-mediated CD40- and interleukin-23p19-specific shRNA can ameliorate experimental autoimmune encephalomyelitis by suppressing T helper type 17 cells
Authors: Kalantari T , Karimi M H , Ciric B , Yan Y , Rostami A , Kamali-Sarvestani E
Published: January 2014

Down-regulation of soluble or membrane-bound co-stimulatory molecules by RNAi in dendritic cells can prevent the activation of immune responses. Therefore, this study was designed to evaluate the therapeutic efficacy of bone marrow-derived DCs (BMDCs) transduced with lentiviral vectors to permanently expressed shRNA specific for CD40 (CD40LV-DCs) and/or p19 subunit of interleukin (IL)-23 (p19LV-DCs) mRNAs in experimental autoimmune encephalomyelitis (EAE). In-vitro studies showed that double-transduced BMDCs (CD40+p19LV-DCs) resemble tolerogenic DCs due to profound down-regulation of CD40, lower expression of proinflammatory cytokines (IL-6 and IL-12), increased IL-10 production and stronger stimulation of myelin oligodendrocyte glycoprotein (MOG)35–55-specific T cells for production of IL-10 compared with CD40LV-DCs, p19LV-DCs and BMDCs transduced with control lentiviral vector (CoLV-DCs). Moreover, injection of transduced CD40+p19LV- BMDCs in EAE mice resulted in more reduction in clinical score, significant reduction in IL-17 or increased production of IL-10 by mononuclear cells derived from the lymph nodes or spinal cord compared with CoLV-DCs-treated EAE mice. In conclusion, simultaneous knock-down of CD40 and IL-23 production by BMDCs may represent a promising therapeutic tool for the treatment of IL-17-dependent autoimmune diseases, including multiple sclerosis.
Effects of bariatric surgery on pericardial ectopic fat depositions and cardiovascular function
Authors: van Schinkel Linda D. , Sleddering Maria A. , Lips Mirjam A. , Jonker Jacqueline T. , de Roos Albert , Lamb Hildo J. , Jazet Ingrid M. , Pijl Hanno , Smit Johannes W. A.
Published: January 2014

Objective

Cardiac ectopic fat depositions are thought to play a role in the pathogenesis of cardiovascular disease (CVD), the main cause of death in patients with type 2 diabetes. Diet‐induced weight loss results in a decrease in cardiac ectopic fat stores, however if this is the same for surgically induced weight loss is less clear. Therefore, we assessed myocardial triglyceride (TG) content, pericardial fat and cardiac function in obese patients with insulin‐dependent type 2 diabetes before and 16 weeks after Roux‐en‐Y gastric bypass (RYGB) surgery.

Patients

Ten obese patients with insulin‐dependent type 2 diabetes [40% male, age 53·7 ± 8·9 years (mean ± SD)] scheduled to undergo RYGB surgery were included.

Measurements

Ectopic fat accumulation and cardiovascular function were assessed with magnetic resonance (MR) imaging and myocardial TG content with MR spectroscopy before and 16 weeks after RYGB surgery.

Results

Body mass index decreased from 41·3 ± 4·3 at baseline to 34·1 ± 2·8 kg/m2 (P < 0·001) after 16 weeks. Glycemic control improved as well [HbA1c: 7·8 ± 1·1 to 6·8 ± 1·3% (62 ± 12 to 51 ± 14 mm) (P < 0·05)]. We did not observe an effect of the RYGB surgery on myocardial TG content, cardiac function or pulse wave velocity. There was a greater relative decrease in visceral (−35·5 ± 9·6%) as compared to subcutaneous fat volume (−25·0 ± 6·3%) and in paracardial (−17·3 ±17·2%) as compared to epicardial fat volume (−6·4 ± 6·0%).

Conclusions

This study shows that surgical‐induced weight loss leads to a larger decrease in paracardial than epicardial fat. Myocardial TG and cardiovascular function did not change.
Does democratization spur growth?
Authors: Assiotis Andreas , Sylwester Kevin
Published: January 2014

Many studies have considered how democratization affects economic growth. We expand this work by allowing short‐ and long‐run effects of democracy upon growth to differ since effects during political transitions need not coincide with those under established democracies. We also allow these short‐ and long‐run effects to differ across world regions since history, demography and geography vary across regions. Using annual, cross‐county data from 1960 to 2010, we find that democratizations increased growth rates in sub‐Saharan Africa both in the short run and in the long run but lowered them in Europe. Effects in other regions appear less strong. Our results suggest that democracy could be most beneficial for growth in poorer, less stable regions. We also do not find any evidence of a transitional cost. Stronger evidence arises that these effects come from rising productivity rather than through greater investment. Finally, some support though mixed suggests that democracy's ability to mitigate the effects of ethnic heterogeneity provides a partial explanation for the cross‐regional heterogeneity.
The sudden collapse of pollinator communities
Authors: Lever J. Jelle , van Nes Egbert H. , Scheffer Marten , Bascompte Jordi
Published: January 2014

Declines in pollinator populations may harm biodiversity and agricultural productivity. Little attention has, however, been paid to the systemic response of mutualistic communities to global environmental change. Using a modelling approach and merging network theory with theory on critical transitions, we show that the scale and nature of critical transitions is likely to be influenced by the architecture of mutualistic networks. Specifically, we show that pollinator populations may collapse suddenly once drivers of pollinator decline reach a critical point. A high connectance and/or nestedness of the mutualistic network increases the capacity of pollinator populations to persist under harsh conditions. However, once a tipping point is reached, pollinator populations collapse simultaneously. Recovering from this single community‐wide collapse requires a relatively large improvement of conditions. These findings may have large implications for our view on the sustainability of pollinator communities and the services they provide.
Fracture‐focused fluid flow in an acid and redox‐influenced system: diagenetic controls on cement mineralogy and geomorphology in the Navajo Sandstone
Authors: Bell J. H. , Bowen B. B.
Published: January 2014

Differential cement mineralogy is influenced by depositional textures, structural deformation, pore fluid chemistry, and ultimately influences landscape evolution by introducing heterogeneities in erodibility. In Southern Utah, the region West of the Kaibab uplift known as Mollies Nipple (Mollies) in Grand Staircase‐Escalante National Monument exhibits a complex history of fluid–sediment interactions, which has resulted in a localized zone of anomalous diagenetic iron sulfate (jarosite) mineralogy in a well‐exposed dune–interdune deposit within the Navajo Sandstone. Mineralogy and geochemistry of cements within this region are examined using reflectance and imaging spectroscopy, field investigations, microscopy, and whole‐rock geochemical analyses. These data show that the in‐situ jarosite cement is localized to a plane along the highest ridge of the butte, providing an armor along with other secondary cements, which controls the butte's geomorphic evolution. The jarosite cement is associated with other mineralogies suggesting that the sulfate was one of the latest fluid‐related precipitates in the paragenetic sequence. It was preceded by a regional bleaching event, precipitation of clay cements, some localized concretionary iron oxide precipitation, and formation of deformation bands. At least one generation of dense iron oxide mineralization is associated with cataclastic brittle deformation predating the sulfate precipitation. Trace element geochemistry of cements shows certain metal oxide populations associated with extremely high (>2000 ppm) arsenic values. We interpret the combination of spatial mineral distribution, observed paragenetic sequence, and trace element geochemistry to suggest this region experienced acid sulfate diagenesis along fracture‐controlled fluid conduits related to weathering of proximal, unidentified, sulfides, or H2S associated with deep source beds. Jarosite is highly soluble, and its presence suggests that abundant fluid flow has not occurred in this region since its formation. This terminal cement‐forming event must have occurred prior to sandstone exhumation and erosion to form the current extreme landscape at Mollies. This site exhibits the influence that fluid geochemistry, sedimentary mineralogy, and structural fabric have on geomorphic evolution.
Cyclic fatigue resistance of ProTaper Next nickel‐titanium rotary files
Authors: Elnaghy A. M.
Published: January 2014

Aim

To compare the cyclic fatigue resistance of ProTaper Next files (PTN; Dentsply Maillefer, Ballaigues, Switzerland) with Twisted Files (TF; SybronEndo, Orange, CA, USA), HyFlex CM (HF; ColténeEndo/Whaledent, Inc, Cuyahoga Falls, OH, USA) and ProTaper Universal (PT; Dentsply Maillefer).

Methodology

Size 25, .06 taper for PTN X2, TF, HF and PT F1 size 20, .07 taper were rotated in simulated canals until failure, and the number of cycles to failure (NCF) was recorded to evaluate their cyclic fatigue resistance. A scanning electron microscope was used to characterize the topographic features of the fracture surfaces of broken files. The data of the NCF and fragment length values were analysed statistically using one‐way analysis of variance and Tukey post hoc tests. Statistical significance level was set at P < 0.05.

Results

Twisted Files had a significantly higher resistance to cyclic fatigue than the other instruments (P < 0.05). No significant difference was found in NCF between PTN and HF (P > 0.05); however, there was a significant difference (P < 0.05) of both these systems with PT, which exhibited the lowest mean NCF. The ranking in the NCF values was: TF > PTN > HF > PT. The fracture cross‐sections of all brands revealed similar fractographic features, including crack origins, fatigue zone and an overload fast fracture zone.

Conclusions

The new ProTaper Next had greater resistance to cyclic fatigue compared with ProTaper and HyFlex CM but not the Twisted Files.
The Elements and Principles of Design: A Baseline Study
Authors: Adams Erin
Published: January 2014

Critical to the discipline, both professionally and academically, are the fundamentals of interior design. These fundamentals include the elements and principles of interior design: the commonly accepted tools and vocabulary used to create and communicate successful interior environments. Research indicates a lack of consistency in both the identification of what constitutes the elements and principles of design and the specific definitions for each of them. Elements and principles of design vary from textbook to textbook, and this lack of consistency must be addressed when creating a single cohesive interior design vocabulary. This research study sought to gather fundamental information pertaining to the elements and principles of design, such as types of class formats being employed, foundational textbooks utilised, and within each curriculum where the elements and principles were being introduced in CIDA‐accredited interior design programmes. Furthermore, this study assessed the attitudes and perceptions of interior design educators concerning the elements and principles of interior design. The elements and principles of interior design are an integral part of design students' education and will contribute substantially to their skill set in the professional realm. For this reason, it is important that the design elements and principles are taught in a consistent manner, with emphasis placed on their meanings, substance and appropriate applications.
Additional Local Therapy With Primary Re‐Excision or Radiation Therapy Improves Survival and Local Control After Incomplete or Close Surgical Excision of Mast Cell Tumors in Dogs
Authors: Kry Kristin L. , Boston Sarah E.
Published: January 2014

Objective

To compare survival and local recurrence outcomes in dogs with mast cell tumors with incomplete or close margins treated with primary re‐excision or radiation therapy of the primary site versus no additional local therapy.

Study Design

Retrospective case series.

Animals

Dogs (n = 64).

Methods

Outcomes of canine mast cell tumor cases that had incomplete or close surgical resection and presented to the Ontario Veterinary College Health Sciences Centre (2001–2010) were evaluated after additional local therapy (primary re‐excision or radiation therapy) or no additional local therapy (comparison). Follow‐up was performed through evaluation of medical records and telephone contact with referring veterinarians and owners.

Results

Tumors (n = 70) in 64 dogs were studied. Median survival times for the primary re‐excision (2930 days) and radiation therapy (2194 days) groups were significantly longer than for the comparison (710 days) group. Local recurrence occurred in 13% of the re‐excision group, 8% of the radiation therapy group, and 38% of the comparison group. Although local recurrence rate was not statistically significant for the re‐excision group, time to local recurrence was statistically longer for both the re‐excision and radiation groups. Adjunctive chemotherapy was not associated with improved survival or local control.

Conclusion/Clinical relevance

There is significant improvement in survival and duration of local control when additional local therapy is performed after incomplete or close resection of mast cell tumors. These follow‐up therapies should be recommended to owners when mast cell tumors are incompletely or closely resected.
Extensive Rostral Mandibulectomy for Treatment of Ameloblastoma in a Horse
Authors: Mendez‐Angulo Jose L. , Tatarniuk Dane M. , Ruiz Indalecio , Ernst Nicolas
Published: January 2014

Objective

To report long‐term outcome in a mare that had extensive rostral mandibulectomy to remove an ameloblastoma.

Study Design

Clinical report.

Animals

A 21‐year‐old mare.

Methods

An ameloblastoma, located in the rostral aspect of the mandible, was removed by complete en‐bloc resection of the tumor, removing most of the mandibular symphysis.

Results

The day after surgery, the remaining mandibular symphysis (<5 mm) fractured causing marked instability of the hemi‐mandibles. Partial wound dehiscence occurred 5 days after surgery; however, the mare was able to eat well and the incision healed within 2 weeks. At 18 months, there was bony fusion of the hemi‐mandibles and mild protrusion of the tongue.

Conclusion

Extensive rostral mandibulectomy (up to the caudal edge of the mandibular symphysis) can apparently be performed in a horse without internal or external stabilization, and yield a cosmetic and functional outcome.
School District Income Taxes: New Revenue or a Property Tax Substitute?
Authors: ROSS JUSTIN M. , NGUYEN‐HOANG PHUONG
Published: January 2014

Using a panel of 609 Ohio school districts from 1990 to 2008, this paper investigates the effects of school district income tax on operating property tax revenue. After correcting for endogeneity, the results do indicate a substitution effect that lowers the property tax levy. Despite reduced property taxes, greater income taxation is mostly to increase total revenues. By how much total revenues increase varies widely depending on the relative and absolute sizes of property and income taxes. We also find that school districts were able to increase the amount of the property tax by a greater amount than nonadopting districts in the years following the adoption of income taxes.
In Pursuit of Letters: A History of the Bray Schools for Enslaved Children in Colonial Virginia
Authors: Bly Antonio T.
Published: January 2014

The pursuit of literacy is a central theme in the history of African Americans in the United States. In the Western tradition, as Henry Louis Gates, Jr. and others have observed, people of African descent have been written out of “culture” because they have been identified with oral traditions. In that setting, literacy signifies both reason and civilization. Performance in print earned the laurel of humanity. Consequently, for well over 200 years, the African-American literary tradition has been defined as one in which books talked and a few slave authors achieved, at once, voice and significance by making a book talk back by writing.