bluuebunny/crossref_metadata_2025 huggingface dataset:
Thermal conductivity of nanocrystalline SiGe alloys using molecular dynamics simulations
Authors: Abs da Cruz Carolina , Katcho Nebil A. , Mingo Natalio , Veiga Roberto G. A.
Published: October 2013

We have studied the effect of nanocrystalline microstructure on the thermal conductivity of SiGe alloys using molecular dynamics simulations. Nanograins are modeled using both the coincidence site lattice and the Voronoi tessellation methods, and the thermal conductivity is computed using the Green-Kubo formalism. We analyze the dependence of the thermal conductivity with temperature, grain size L, and misorientation angle. We find a power dependence of L1/4 of the thermal conductivity with the grain size, instead of the linear dependence shown by non-alloyed nanograined systems. This dependence can be derived analytically underlines the important role that disorder scattering plays even when the grains are of the order of a few nm. This is in contrast to non-alloyed systems, where phonon transport is governed mainly by the boundary scattering. The temperature dependence is weak, in agreement with experimental measurements. The effect of angle misorientation is also small, which stresses the main role played by the disorder scattering.
Highly conductive spray deposited poly(3, 4-ethylenedioxythiophene):poly (styrenesulfonate) electrodes for indium tin oxide-free small molecule organic photovoltaic devices
Authors: Unsworth N. K. , Hancox I. , Argent Dearden C. , Howells T. , Sullivan P. , Lilley R. S. , Sharp J. , Jones T. S.
Published: October 2013

Spray deposition is currently attracting significant attention as a low cost method for organic photovoltaic (OPV) device fabrication. We report indium tin oxide (ITO)-free small moleule OPV devices comparing spin coated and spray deposited highly conductive poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) as the transparent conducting electrode (TCE). Conductive atomic force microscopy studies indicate that despite an increase in surface roughness, spray deposited PEDOT:PSS TCEs display a similar distribution in the surface composition of PEDOT and PSS and provide comparable device performance to spin coated PEDOT:PSS TCEs. Therefore, the TCEs fabricated by spray deposition show potential as an inexpensive solution processable alternative to the conventionally used ITO TCE for OPV devices.
Anisotropic-strain-controlled metal-insulator transition in epitaxial NdNiO3 films grown on orthorhombic NdGaO3 substrates
Authors: Lian X. K. , Chen F. , Tan X. L. , Chen P. F. , Wang L. F. , Gao G. Y. , Jin S. W. , Wu W. B.
Published: October 2013

NdNiO3 (NNO) films were grown by pulsed laser deposition on orthorhombic (110)-, (001)-, and (100)-oriented NdGaO3 substrates. It is found that all the films are tensile-strained but show dramatically different metal-insulator transition (MIT) temperatures (TMI) (160–280 K), as compared with the NNO bulk (∼200 K). A high resemblance in the sharpness of MIT and lattice variation across the MIT was observed. The TMI is highly dependent on the magnitude of the orthorhombic distortion induced by the different substrate surface plane and tends to recover the bulk value after annealing. Our results suggest that the anisotropic epitaxial strain can effectively tune the MIT of NNO films, and the NiO6 octahedra rotation and deformation involved in accommodating the tensile strain might cause the different TMI.
Quantum-mechanical calculation of carrier distribution in MOS accumulation and strong inversion layers
Authors: Lee Chien-Wei , Hwu Jenn-Gwo
Published: October 2013

We derive a statistical physics model of two-dimensional electron gas (2DEG) and propose an accurate approximation method for calculating the quantum-mechanical effects of metal-oxide-semiconductor (MOS) structure in accumulation and strong inversion regions. We use an exponential surface potential approximation in solving the quantization energy levels and derive the function of density of states in 2D to 3D transition region by applying uncertainty principle and Schrödinger equation in k-space. The simulation results show that our approximation method and theory of density of states solve the two major problems of previous researches: the non-negligible error caused by the linear potential approximation and the inconsistency of density of states and carrier distribution in 2D to 3D transition region.
The role of structure on magneto-transport properties of Heusler Co2MnSi films deposited on MgO(001)
Authors: Tal N. , Mogilyanski D. , Kovács A. , Naganuma H. , Tsunegi S. , Oogane M. , Ando Y. , Kohn A.
Published: October 2013

We present an experimental study identifying structural reasons that degrade spin-polarization of Co2MnSi thin films deposited on MgO(001) substrates. Through the fabrication of magnetic tunnel junctions, we measure a range of values for tunneling magneto-resistance (TMR) ratios following post-deposition annealing and epitaxial crystallization of the Heusler film. These TMR ratios reflect qualitatively the change in spin polarization of the Co2MnSi thin films. Low-temperature annealing results in low spin-polarization due to a high fraction of an amorphous phase. As annealing temperatures increase, the fraction of L21 and B2 chemically ordered phases increases, thus improving significantly the spin-polarization. However, for samples annealed at higher temperatures, significant degradation in the cubic magneto-crystalline anisotropy is observed, which we attribute to the detection of manganese diffusion into the MgO substrate. This Mn diffusion is manifested in a reduction of the value of the TMR ratio, namely, the spin polarization. Additionally, the maximum TMR ratio measured here, approximately 65% at room-temperature, is limited because the semi-coherent interface of Co2MnSi with the MgO substrate terminates with a Mn-Si layer.
Photochemically induced motion of liquid metal marbles
Authors: Tang Xinke , Tang Shi-Yang , Sivan Vijay , Zhang Wei , Mitchell Arnan , Kalantar-zadeh Kourosh , Khoshmanesh Khashayar
Published: October 2013

We demonstrate photochemically induced actuation of liquid metal marbles, which are liquid metal droplets encased in micro/nanoparticles. The WO3 nanoparticles coated marbles are placed in H2O2 solution, and their surfaces are illuminated with UV light. The semiconducting WO3 coating behaves as a photocatalyst to trigger a photochemical reaction, generating oxygen bubbles that propel the marble. The actuation of the marbles is investigated under different H2O2 concentrations, light intensities, and marble dimensions. Equations describing the fundamentals of such actuations are presented.
Microfluidic production of single micrometer-sized hydrogel beads utilizing droplet dissolution in a polar solvent
Authors: Sugaya Sari , Yamada Masumi , Hori Ayaka , Seki Minoru
Published: October 2013

In this study, a microfluidic process is proposed for preparing monodisperse micrometer-sized hydrogel beads. This process utilizes non-equilibrium aqueous droplets formed in a polar organic solvent. The water-in-oil droplets of the hydrogel precursor rapidly shrunk owing to the dissolution of water molecules into the continuous phase. The shrunken and condensed droplets were then gelled, resulting in the formation of hydrogel microbeads with sizes significantly smaller than the initial droplet size. This study employed methyl acetate as the polar organic solvent, which can dissolve water at 8%. Two types of monodisperse hydrogel beads—Ca-alginate and chitosan—with sizes of 6–10 μm (coefficient of variation < 6%) were successfully produced. In addition, we obtained hydrogel beads with non-spherical morphologies by controlling the degree of droplet shrinkage at the time of gelation and by adjusting the concentration of the gelation agent. Furthermore, the encapsulation and concentration of DNA molecules within the hydrogel beads were demonstrated. The process presented in this study has great potential to produce small and highly concentrated hydrogel beads that are difficult to obtain by using conventional microfluidic processes.
A 4th-order band-pass filter using differential readout of two in-phase actuated contour-mode resonators
Authors: Yagubizade Hadi , Darvishi Milad , Elwenspoek Miko C. , Tas Niels R.
Published: October 2013

A 4th-order band-pass filter (BPF) based on the subtraction of two 2nd-order contour-mode Lamb-wave resonators is presented. The resonators have slightly different resonance frequencies around 380 MHz. Each resonator consists of a 500 nm pulsed-laser deposited lead zirconate titanate (PZT) thin-film on top of a 3 μm silicon (PZT-on-Si). The resonators are actuated in-phase, and their outputs are subtracted. Utilizing this technique, the feed-through signals are eliminated while the outputs of the resonators are added up constructively, due to the phase difference between the two output signals. The BPF is presented using 50 Ω termination with a bandwidth of approximately 3.9 MHz and 43 dB stopband rejection. This technique provides further opportunities for MEMS filter design in addition to existing methods, i.e., mechanical and/or electrical coupling. It also resolves the design issue associated with high feed-through when exploiting piezoelectric materials with high-dielectric constant like PZT.
Potential fluctuations in graphene due to correlated charged impurities in substrate
Authors: Aničić R. , Mišković Z. L.
Published: October 2013

We evaluate the autocorrelation function of the electrostatic potential in doped graphene due to nearby charged impurities. The screening of those impurities is described by a combination of the polarization function for graphene in random phase approximation with the electrostatic Green's function of the surrounding dielectrics. Using the hard-disk model for a two-dimensional distribution of impurities, we show that large correlation lengths between impurities can give rise to anti-correlation in the electrostatic potential, in agreement with recent experiments.
Phase formation during Mn thin film reaction with Ge: Self-aligned germanide process for spintronics
Authors: Abbes O. , Portavoce A. , Le Thanh V. , Girardeaux C. , Michez L.
Published: October 2013

Interesting results have been reported concerning the magnetic properties of the Mn5Ge3 compound, opening the road to possibly create spin injectors in Ge. However, a process compatible with the Complementary Metal Oxide Semiconductor technology, allowing to produce a Mn5Ge3 layer on the active regions of Ge-based transistors has not been well established yet. Here, we report on the solid state reaction between a 50 nm-thick Mn film and amorphous Ge, aiming to investigate a similar process than the one (Salicide) used for contact production in the standard Si technology. In situ X-ray diffraction combined with ex situ structural and magnetic characterizations were used to identify and study phase formation during the Mn/Ge reaction.
Incident hepatitis B infection subsequent to the diagnosis of HIV infection in a Melbourne cohort: missed opportunities for prevention
Authors: Body Amy , Hoy Jennifer F. , Cheng Allen C. , Giles Michelle L.
Published: October 2013

Background
The characteristics associated with incident hepatitis B (HBV) infection in HIV-positive individuals are not well described in the Australian setting. The aim of this study is to determine the characteristics of and risk factors for HBV infection within HIV-infected individuals in a Melbourne cohort between 1985 and 2011. Methods: Individuals susceptible to HBV at their HIV diagnosis were identified using their HBV serology stored within the Victorian HIV database. Within this group, those who had a subsequent positive test for hepatitis B surface antigen or hepatitis B core antibody were identified as infected with HBV after their HIV diagnosis. Incident cases were matched with controls from the initially susceptible group who did not seroconvert for analysis. An incidence rate was calculated from the number of seroconversions and the cumulative time at risk (in 1000 patient-years of follow-up). Results: Of the 4711 patients with HIV seen more than once, 3223 had HBV testing. Of the 174 with positive HBV test results, 39 individuals met the definition of seroconversion after HIV diagnosis, representing the incident cases. The estimated HBV incidence rate was 1.81 (95% confidence interval: 1.28–2.47) per 1000 patient-years at risk. These individuals form the basis of a detailed case series and case–control study. Data collected include demographic details, immunological and virological characteristics, antiretroviral treatment and vaccination history. Conclusions: HIV-infected individuals should be screened for HBV and monitored for incident infection. Optimal control of HIV and improved vaccination coverage provide the best opportunity for prevention.
Pheromone discrimination by a pH-tuned polymorphism of the
Bombyx mori
pheromone-binding protein
Authors: Damberger Fred F. , Michel Erich , Ishida Yuko , Leal Walter S. , Wüthrich Kurt
Published: October 2013

Significance

Pheromone recognition by insect olfactory organs is critical for the ability of insects to locate mates. The silkworm moth
Bombyx mori
has long served as a model organism for studies of this process. Key components in the sensory organs have been identified, including the pheromone bombykol, pheromone-binding protein (BmorPBP), ligand-degrading enzymes, and the pheromone receptor, but many details of the mechanism allowing highly sensitive and selective pheromone detection are still elusive. Here, it is shown that a pH-dependent conformational polymorphism of BmorPBP affords highly selective transport of the pheromone, demonstrating an active role for BmorPBP in ligand discrimination.
Value Learning Modulates goal-Directed Actions
Authors: Painter David R. , Kritikos Ada , Raymond Jane E.
Published: October 2013

With experience, particular objects can predict good or bad outcomes. This alters our perceptual response to them: Reliable predictors of salient outcomes are recognized faster and better than unreliable predictors, regardless of the value (gain, loss) of the outcome they predict. When attentional resources are constrained, learned value associations matter, causing recognition of gain-associated objects to be spared. Here, we ask how learned predictiveness and value change the way we interact with potentially rewarding objects. After associating virtual objects (drinking flutes) with monetary gains or losses, reaching for and grasping corresponding real objects depended on the object's learned value. Action was faster when directed at objects that previously predicted outcomes more rather than less consistently, regardless of value. Conversely, reaches were more direct for gain- than for loss-associated objects, regardless of their predictiveness. Action monitoring thus reveals how value learning components become accessible during action.
Calculation of Compensation and Damages in International Investment Law
Authors: Marboe Irmgard
Published: October 2013

The importance of calculation and valuation matters in investment arbitration has long been underestimated. Only recently, there is a growing understanding that financial aspects play an equally important role for claimants and respondents as the purely legal bases of claims. Also for general preventive reasons the amounts awarded should as closely as possible reflect economic realities. The book tries to combine the various types of claims – based on expropriations, violations of international law (i.e. mostly BIT-violations) and contract breaches – with internationally accepted valuation standards and approaches. In doing so, it puts an emphasis on the specific function of compensation and damages. This functional approach is characteristic for the entire book, including the chapter on interest where the different functions of ‘pre-award interest’ and ‘post-award interest’ are highlighted. After a short general introduction in Chapter 1, Chapter 2 analyses the function of compensation and damages in international investment disputes. It shows that compensation upon expropriation serves a different function than damages after an unlawful act, be it a breach of a treaty, such as a BIT, or a contract. It concludes that an appropriate valuation approach should reflect these functions. Chapter 3 gives an outline of the legal framework of compensation and damages in international investment law. Starting from the standard of compensation upon expropriation under international law it analyses the difference between lawful and unlawful expropriations. It then examines the criteria of the calculation in cases of State responsibility and breaches of contract. Chapter 4 introduces some internationally recognized valuation standards and bases of value. Chapter 5 analyses how the three most important valuation approaches – the market approach, the income approach, and the asset based or cost approach – are reflected in the practice of international investment tribunals. Chapter 6 discusses the most important issues with regard to the determination of interest, namely the rate of interest, the period of interest, and the question of whether interest should be compounded, and underlines the difference between ‘pre-award interest’ and ‘post-award interest’. Chapter 7 summarizes the most important economic and legal principles and filters out some guidelines for application in practice.
Complete history of the observable 21 cm signal from the first stars during the pre-reionization era
Authors: Fialkov Anastasia , Barkana Rennan , Pinhas Arazi , Visbal Eli
Published: October 2013

We present the first complete calculation of the history of the inhomogeneous 21 cm signal from neutral hydrogen during the era of the first stars. We use hybrid computational methods to capture the large-scale distribution of the first stars, whose radiation couples to the neutral hydrogen emission, and to evaluate the 21 cm signal from z ∼ 15–35. In our realistic picture, large-scale fluctuations in the 21 cm signal are sourced by the inhomogeneous density field and by the Lyα and X-ray radiative backgrounds. The star formation is suppressed by two spatially varying effects: negative feedback provided by the Lyman–Werner radiative background, and supersonic relative velocities between the gas and dark matter. Our conclusions are quite promising: we find that the fluctuations imprinted by the inhomogeneous Lyα background in the 21 cm signal at z ∼ 25 should be detectable with the Square Kilometre Array.
Joining or opting out of a Lotka–Volterra game between predators and prey: does the best strategy depend on modelling energy lost and gained?
Authors: Staňková Kateřina , Abate Alessandro , Sabelis Maurice W. , Buša Ján , You Li
Published: October 2013

Apart from interacting, prey and predators may also avoid each other by moving into refuges where they lack food, yet survive by switching to an energy-saving physiological state. Lotka–Volterra models of predator–prey interactions ignore this option. Therefore, we have modelled this game of ‘joining versus opting out’ by extending Lotka–Volterra models to include portions of populations not in interaction and with different energy dynamics. Given this setting, the prey's decisions to join or to opt out influence those of the predator and vice versa, causing the set of possible strategies to be complex and large. However, using game theory, we analysed and published two models showing (i) which strategies are best for the prey population given the predator's strategy, and (ii) which are best for prey and predator populations simultaneously. The predicted best strategies appear to match empirical observations on plant-inhabiting predator and prey mites. Here, we consider a plausible third model that does not take energy dynamics into account, but appears to yield contrasting predictions. This supports our assumption to extend Lotka–Volterra models with ‘interaction-dependent’ energy dynamics, but more work is required to prove that it is essential and that what is best for the population is also best for the individual.
Different functions of the common P/V/W and V-specific domains of rinderpest virus V protein in blocking IFN signalling
Authors: Chinnakannan Senthil K. , Holzer Barbara , Bernardo Beatriz Sanz , Nanda Sambit K. , Baron Michael D.
Published: October 2013

The V proteins of paramyxoviruses are composed of two evolutionarily distinct domains, the N-terminal 75 % being common to the viral P, V and W proteins, and not highly conserved between viruses, whilst the remaining 25 % consists of a cysteine-rich V-specific domain, which is conserved across almost all paramyxoviruses. There is evidence supporting a number of different functions of the V proteins of morbilliviruses in blocking the signalling pathways of type I and II IFNs, but it is not clear which domains of V are responsible for which activities and whether all these activities are required for effective blockade of IFN signalling. We have shown here that the two domains of rinderpest virus V protein have distinct functions: the N-terminal domain acted to bind STAT1, whilst the C-terminal V-specific domain interacted with the IFN receptor-associated kinases Jak1 and Tyk2. Effective blockade of IFN signalling required the intact V protein.
Comprehension of sarcasm, metaphor and simile in Williams syndrome
Authors: Godbee Kali , Porter Melanie
Published: October 2013

Background

Although people with Williams syndrome (WS) are often characterized as friendly and sociable with relatively good general language abilities, there is emerging evidence of pragmatic difficulties and trouble comprehending aspects of non‐literal language.

Aims

The main aim was to investigate the comprehension of sarcasm, metaphor and simile in WS relative to typically developing controls. A secondary aim was to examine the association between non‐literal language comprehension and a range of other cognitive abilities, both in WS and in the typically developing population.

Methods & Procedures

Twenty‐six participants with WS were compared with 26 typically developing chronological age‐matched controls (TDCA) and 26 typically developing mental age‐matched controls (TDMA). Participants listened to stories in which characters made non‐literal comments. They were then asked what each character meant by their comment. In order to investigate the second aim of the study, cognitive abilities were also assessed using the Woodcock–Johnson (Revised) Tests of Cognitive Ability, including expressive vocabulary, verbal working memory, perceptual integration, inferential reasoning and overall cognitive ability.

Outcomes & Results

Comprehension of non‐literal language in WS was significantly below TDCA levels, but was not significantly different to TDMA levels. For typically developing controls, each of the cognitive measures was strongly correlated with each of the measures of non‐literal language comprehension. The same relationships were not always found for participants with WS. In particular, sarcasm comprehension in WS was not significantly correlated with any of the assessed cognitive abilities, and expressive vocabulary was not significantly correlated with any measure of non‐literal comprehension.

Conclusions & Implications

Comprehension of simile in WS is below TDCA levels but seems on par with their mental age level. It appears that comprehension of sarcasm and metaphors is above the cognitive capabilities and mental age level of most individuals with WS. Further, the pattern of correlations between non‐literal comprehension and cognitive abilities in WS relative to controls suggests that perhaps the linguistic and cognitive systems that underpin non‐literal language comprehension in typically developing individuals interact and integrate in different ways in WS.
Democracy or Stability? European Approaches to Justice in Peace and Transitional Processes
Authors: Rangelov Iavor
Published: October 2013

Debates over justice for gross human rights violations in active conflicts and transitions are often framed as a dilemma that emphasizes perceived tensions between human rights and democracy on one side and peace and stability on the other. Despite the prominence of the justice dilemma in the scholarly literature, little attention has been directed to examining its significance for global policy making. Beyond the rhetoric, it is unclear whether the dilemma frames the issues for key international actors and how it shapes their policies. This article addresses this gap by investigating the role of the justice dilemma in the foreign policy of the EU. First, it traces the origins of the dilemma and highlights important continuities in its framing over time. It then demonstrates how in pursuing ‘democratization’ and ‘stabilization’ approaches to justice, the EU often reproduces the underlying assumptions, perceived tensions and conventional solutions that circulate in scholarly and policy discussions. The final section examines the implications of the justice dilemma for European policy making. The article argues that the EU's preoccupation with the dilemma limits its ability to develop effective and innovative policies in this important field.
Ultrasound‐guided compared to conventional treatment in gestational diabetes leads to improved birthweight but more insulin treatment: systematic review and meta‐analysis
Authors: Balsells Montserrat , García‐Patterson Apolonia , Gich Ignasi , Corcoy Rosa
Published: October 2013

Objective

To perform a systematic review and meta‐analysis of randomized controlled trials assessing ultrasound‐guided versus conventional management in women with a broad severity‐spectrum of gestational diabetes mellitus.

Design

Systematic review and meta‐analysis of trials published until August 2012.

Setting

PubMed and Web of Science databases.

Study selection and methods

Eighteen studies were reviewed in full text. Eligibility criteria were (i) randomized controlled trials comparing metabolic management in women with gestational diabetes mellitus and ultrasound‐based vs. the conventional management to assess fetal growth, (ii) representative of the whole spectrum of hyperglycemia and fetal growth, (iii) data on perinatal outcomes. Review Manager 5.0 was used to summarize the results.

Results

Two studies fulfilled inclusion criteria. The ultrasound‐guided group had a lower rate of large‐for‐gestational age newborns (relative risk 0.58, 95% confidence interval 0.34–0.99), macrosomia (relative risk 0.32, 95% confidence interval 0.11–0.95) and abnormal birthweight (small/large‐for‐gestational age, relative risk 0.64, 95% confidence interval 0.45–0.93) and a higher rate of insulin treatment (relative risk 1.58, 95% confidence interval 1.14–2.20). The number of women with gestational diabetes with a need to treat to prevent an additional newborn with abnormal birthweight was 10.

Conclusions

In women with a broad severity‐spectrum of gestational diabetes mellitus, ultrasound‐guided management improves birthweight distribution, but increases the need for insulin treatment. More research is needed in this area because results are derived from a limited number of patients.
L‐3‐n‐butylphthalide protects rats' cardiomyocytes from ischaemia/reperfusion‐induced apoptosis by affecting the mitochondrial apoptosis pathway
Authors: Wang Y.‐G. , Li Y. , Wang C.‐Y. , Ai J.‐W. , Dong X.‐Y. , Huang H.‐Y. , Feng Z.‐Y. , Pan Y.‐M. , Lin Y. , Wang B.‐X. , Yao L.‐L.
Published: October 2013

Aims

This study investigated the role of L‐3‐n‐Butylphthalide (NBP) in cardiac protection.

Methods

The left anterior descending coronary arteries (LAD) of the rats were occluded for 30 min following by 2‐h reperfusion to make the ischaemia/reperfusion models. Neonatal cardiomyocytes were cultured and subjected to hypoxia. L‐3‐n‐Butylphthalide was administered intraperitoneally 2 h before the surgery and right after the reperfusion in the in vivo experiments or added to the culture medium in vitro. Haemodynamic parameters were recorded to evaluate the cardiac functions, triphenyltetrazolium chloride (TTC) and Evens blue staining were used to determine the area of risk and infarct area, apoptotic cell numbers were counted with terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) staining. Western blotting was used to determine the apoptotic protein levels and immune staining to determine the translocation of Glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH) protein.

Results

Our research showed for the first time that L‐3‐n‐Butylphthalide had great effects in improving cardiac hemodynamic function and decreasing cardiac infarct areas and apoptotic cell numbers in the peri‐infarct areas. The apoptotic signals investigation showed that L‐3‐n‐Butylphthalide affected the mitochondrial pathway including Bcl‐2 protein expression, inhibition of caspase 3 activation and cytochrome C releasing. Besides, Glyceraldehyde‐3‐phosphate dehydrogenase protein translocation was inhibited by L‐3‐n‐Butylphthalide treatment, and this effect was mediated by endogenous reactive oxygen species (ROS).

Conclusion

L‐3‐n‐Butylphthalide protects cardiomyocytes from ischaemia/reperfusion‐induced apoptosis by antioxidant effect and affecting mitochondrial apoptotic pathway.
The Impact of recovery methods on taxonomic richness in Roman faunal assemblages
Authors: Trusler A. K.
Published: October 2013

Recovery methods can affect species richness in faunal assemblages, which can in turn impact interpretations of diet. A comparison of sample size to species richness across faunal collections from screened and from unscreened deposits associated with Roman occupations clearly shows these influences. Not surprisingly, the rate of species input was higher for collections recovered using screening methods than for collections not recovered from screens. Syntheses of published data and comparative analyses of faunal assemblages must be cognizant of whether or not included assemblages were recovered using screens.
Advances in laparoscopic colorectal surgery: A review on NOTES and transanal extraction of specimen
Authors: Leung Alex Lik Hang , Cheung Hester Yui Shan , Li Michael Ka Wah
Published: October 2013

Laparoscopic colorectal surgery has rapidly developed since the 1980s. Relative to open surgery, it offers the benefits of less invasiveness and earlier recovery. However, when a mini‐laparotomy wound is needed to retrieve the specimen, the benefits of minimally invasive surgery may be compromised as a result of pain‐ and wound‐related complications. The introduction of natural orifice transluminal endoscopic surgery (NOTES) makes “scarless” surgery a possibility; pain‐ and wound‐related complications are totally abolished. However, a number of technical issues need to be overcome before this technique can be used widely. The development of natural orifice specimen extraction surgery abandons the need for a specimen‐retrieval incision and helps overcome the technical hurdles of NOTES. As a bridge between true “scarless” surgery and conventional laparoscopic surgery, hybrid procedures combining laparoscopic resection and natural orifice specimen extraction surgery currently play an important role in minimally invasive colorectal surgery.
Predicting bipolar disorder on the basis of phenomenology: implications for prevention and early intervention
Authors: Malhi Gin S , Bargh Danielle M , Coulston Carissa M , Das Pritha , Berk Michael
Published: October 2013

Objective

Bipolar disorder is a multifaceted illness and there is often a substantial delay between the first onset of symptoms and diagnosis. Early detection has the potential to curtail illness progression and disorder‐associated burden but it requires a clear understanding of the initial bipolar prodrome. This article summarizes the phenomenology of bipolar disorder with an emphasis on the initial prodrome, the evolution of the illness, and the implications for prevention and early intervention.

Methods

A literature review was undertaken using Medline, Web of Science, and a hand search of relevant literature using keywords (e.g., phenomenology, initial or early symptoms, risk factors, and predictors/prediction). Findings from the literature were reviewed and synthesized and have been put into a clinical context.

Results

Bipolar disorder is a recurrent, persistent, and disabling illness that typically develops in adolescence or early adulthood. The literature search yielded 28 articles, in which mood lability, nonspecific, non‐mood symptoms, and cyclothymic temperament were the most cited prodromal features.

Conclusions

A small number of key prospective studies have provided evidence in support of an initial bipolar prodrome; however, methodological differences across studies have prohibited its clear delineation. It is, therefore, not currently possible to anticipate those who will develop bipolar disorder solely on the basis of early phenomenology. Accurate characterization of the bipolar disorder prodrome through high‐quality, prospective research studies with adequate control groups will ultimately facilitate prompt and accurate diagnosis.
Perivascular fat, AMP‐activated protein kinase and vascular diseases
Authors: Almabrouk T A M , Ewart M A , Salt I P , Kennedy S
Published: October 2013

Perivascular adipose tissue (PVAT) is an active endocrine and paracrine organ that modulates vascular function, with implications for the pathophysiology of cardiovascular disease (CVD). Adipocytes and stromal cells contained within PVAT produce mediators (adipokines, cytokines, reactive oxygen species and gaseous compounds) with a range of paracrine effects modulating vascular smooth muscle cell contraction, proliferation and migration. However, the modulatory effect of PVAT on the vascular system in diseases, such as obesity, hypertension and atherosclerosis, remains poorly characterized. AMP‐activated protein kinase (AMPK) regulates adipocyte metabolism, adipose biology and vascular function, and hence may be a potential therapeutic target for metabolic disorders such as type 2 diabetes mellitus (T2DM) and the vascular complications associated with obesity and T2DM. The role of AMPK in PVAT or the actions of PVAT have yet to be established, however. Activation of AMPK by pharmacological agents, such as metformin and thiazolidinediones, may modulate the activity of PVAT surrounding blood vessels and thereby contribute to their beneficial effect in cardiometabolic diseases. This review will provide a current perspective on how PVAT may influence vascular function via AMPK. We will also attempt to demonstrate how modulating AMPK activity using pharmacological agents could be exploited therapeutically to treat cardiometabolic diseases.
Differential interactions of antiretroviral agents with LXR, ER and GR nuclear receptors: potential contributing factors to adverse events
Authors: Svärd J , Blanco F , Nevin D , Fayne D , Mulcahy F , Hennessy M , Spiers J P
Published: October 2013

Background and Purpose

Antiretroviral (ARV) drugs activate pregnane X receptors and constitutive androstane receptors, increasing the risk of drug interactions due to altered drug metabolism and disposition. The closely related liver X receptors (LXRα/β), oestrogen receptors (ERα/β) and glucocorticoid receptor (GR) regulate many endogenous processes such as lipid/cholesterol homeostasis, cellular differentiation and inflammation. However, ARV drug activation of these nuclear receptors has not been thoroughly investigated.

Experimental Approach

The ability of an ARV drug library to activate LXRα/β, ERα/β and GR was assessed using a combined in silico and in vitro approach encompassing computational docking and molecular descriptor filtering, cell‐free time‐resolved fluorescence resonance energy transfer co‐activator assays to assess direct binding to ligand‐binding domains (LBDs), cell‐based reporter assays and target gene expression.

Key Results

Direct LBD interactions with LXRα and/or LXRβ were predicted in silico and confirmed in vitro for darunavir, efavirenz, flavopiridol, maraviroc and tipranavir. Likewise, efavirenz was also predicted and confirmed as a ligand of ERα‐LBD. Interestingly, atazanavir and ritonavir also activated LXRα/β in reporter assays, while tipranavir enhanced transcriptional activity of ERα. Effects on ER and LXR target gene expression were confirmed for efavirenz and tipranavir.

Conclusions and Implications

There was good agreement between in silico predictions and in vitro results. However, some nuclear receptor interactions identified in vitro were probably due to allosteric effects or nuclear receptor cross‐talk, rather than direct LBD binding. This study indicates that some of the adverse effects associated with ARV use may be mediated through ‘off‐target’ effects involving nuclear receptor activation.
Constitutive activation of AMPK α1 in vascular endothelium promotes high‐fat diet‐induced fatty liver injury: role of COX‐2 induction
Authors: Liang Yan , Huang Bosheng , Song Erfei , Bai Bo , Wang Yu
Published: October 2013

Background and Purpose

AMP‐activated protein kinase (AMPK), an important regulator of energy metabolism, comprises three (α, β and γ) subunits, each with a unique tissue distribution. As AMPK has a wide range of protein and gene targets, defining its role has been difficult. Here, we have studied a transgenic mouse model overexpressing the constitutively active α1 subunit of AMPK in endothelial cells (EC‐AMPK) to elucidate its role in energy homeostasis.

Experimental Approach

Wild‐type and EC‐AMPK mice were fed with a high fat diet for 16 weeks. Drugs (or vehicles) were given daily by oral gavage. Body weight, fat mass composition, glucose and lipid levels were monitored regularly. Tissues including aortae and liver were collected for quantitative RT‐PCR, Western blotting, elisa, histological and biochemical evaluations.

Key Results

Compared with wild‐type animals, high fat diet caused more severe metabolic defects in EC‐AMPK mice, which exhibited increased body weight and fat mass, elevated blood pressure, augmented glucose and lipid levels, impaired glucose tolerance, hepatomegaly and steatohepatitis. Constitutive activation of AMPK α1 in endothelial cells induced COX‐2 expression and arterial inflammation. Genes involved in lipid metabolism were down‐regulated in aortae and livers of EC‐AMPK mice. Chronic treatment with selective COX‐2 inhibitors, celecoxib or nimesulide, significantly ameliorated arterial inflammation, steatohepatitis and hyperlipidaemia in EC‐AMPK mice, without altering their blood pressure or clotting.

Conclusions and Implications

Constitutive activation of endothelial AMPK α1 promotes vascular inflammation and the development of obesity‐induced fatty livers largely via induction of COX‐2.
A Multidimensional Analysis of Public Environmental Concern in Canada
Authors: Zhou Min
Published: October 2013

Cet article aborde la question du souci de l'environnement chez les Canadiennes et Canadiens à partir des données du World Values Survey 2006. Les résultats démontrent qu'il existe une relation significative entre d'une part l’éducation, le niveau de connaissance par rapport aux problèmes environnementaux et l'allégeance politique, et d'autre part le niveau de souci de l'environnement. Les individus ayant un plus haut niveau d’éducation et une plus grande connaissance des problèmes environnementaux sont plus susceptibles de se soucier de l'environnement. Le niveau de souci de l'environnement est de plus polarisé selon l'allégeance politique, en ce sens que les individus s'identifiant comme étant politiquement de gauche montrent un plus haut niveau de souci de l'environnement que ceux qui s'identifient comme de droite. L'analyse met également de l'avant le caractère multi‐dimensionnel du souci de l'environnement : alors que certaines personnes montrent une plus grande conscience des menaces à l'environnement ou encore une plus grande disposition à débourser de l'argent pour assurer la protection de l'environnement, d'autres sont plus enclines à participer directement aux activités d'organisations environnementalistes.

This article uses the 2006 World Values Survey data to examine which Canadians are most concerned about the environment. The results show that those individuals who have more education and greater knowledge of global environmental degradation are more likely to be concerned about the environment. Environmental concern in Canada is also politicized in that liberals are more concerned about the environment than conservatives. The results also show that environmental concern is multidimensional. Although some Canadians show more awareness of environmental threat and more willingness to pay for environmental protection, others are more likely to directly participate in environmental organizations.
Volarea – A Bioinformatics Tool to Calculate the Surface Area and the Volume of Molecular Systems
Authors: Ribeiro João V. , Tamames Juan A. C. , Cerqueira Nuno M. F. S. A. , Fernandes Pedro A. , Ramos Maria J.
Published: October 2013

We have developed a computer program named ‘VolArea’ that allows for a rapid and fully automated analysis of molecular structures. The software calculates the surface area and the volume of molecular structures, as well as the volume of molecular cavities. The surface area facility can be used to calculate the solvent‐exposed surface area of a molecule or the contact area between two molecules. The volume algorithm can be used to predict not only the space occupied by any molecular structure, but also the volume of cavities, such as tunnels or clefts. The software finds wide application in the characterization of systems, such as protein/ligand complexes, enzyme active sites, protein/protein interfaces, enzyme channels, membrane pores, solvent tunnels, among others. Some examples are given to illustrate its potential. VolArea is as a plug‐in of the widely distributed software Visual Molecular Dynamics (VMD) and is freely available at http://www.fc.up.pt/PortoBioComp/Software/Volarea/Home.html.
Identification of Type II Inhibitors Targeting BRAF Using Privileged Pharmacophores
Authors: Zhang Qingwen , Wang Juan , Wang Fei , Chen Xiuhua , He Yunsong , You Qidong , Zhou Houyuan
Published: October 2013

V‐RAF murine sarcoma viral oncogene homologue B1 (BRAF) is the most frequently mutated protein kinase in human cancers. The most common mutant BRAF V600E constitutively activates the RAS/RAF/MEK/ERK signaling pathway. BRAF has been validated as an important therapeutic target in human cancers. Phenylaminopyrimidine and unsymmetrical diaryl urea are two privileged pharmacophores in kinase inhibitor drug discovery. Herein, we describe the design of a novel hybrid pharmacophore, 4‐phenylaminopyrimidine urea, using the above two pharmacophores. A new series of compounds were in turn synthesized and evaluated to successfully identify selective inhibitors of BRAF and oncogenic BRAF V600E. Once daily oral dosing of lead compound 3 demonstrated sustained antitumor efficacy in A549 human non‐small‐cell lung cancer xenograft model. Molecular docking suggested that compound 3 might be a type II kinase inhibitor binding to the DFG‐out conformation of BRAF.
The psychological and social impact of camp for children with chronic illnesses: a systematic review update
Authors: Moola F. J. , Faulkner G. E. J. , White L. , Kirsh J. A.
Published: October 2013

Advances in medicine have reduced mortality among children with complex medical conditions, resulting in a growing number of young patients living with chronic illnesses. Despite an improved prognosis, these children experience significant psychosocial morbidity, such as depression and anxiety. Therapeutic summer recreation camps have been proposed as an intervention to enhance quality of life among these children. The purpose of this systematic review was to assess the psychosocial impact of camp for children with chronic illnesses. A systematic review of central databases was undertaken using key words, and a rating tool – the Effective Public Health Practice Project (EPHPP) Quality Assessment Tool for Quantitative Studies – was employed to rate methodological quality. 21 studies were included in this systematic review. Although overall methodological quality was weak, camp participation appeared to offer short‐term psychosocial benefits on some parameters in children with a variety of chronic illnesses. There was some consistency in improved social outcomes, such as social interaction and acceptance. Based on the available evidence, it is premature to make robust claims regarding the psychosocial impact of camp as a therapeutic intervention. Theoretically informed camp programs, long‐term follow‐up, and incorporating camp‐based messaging into routine hospital care, may enhance the utility of camp as a potential psychosocial intervention in paediatrics.
Effect of midazolam on cardiopulmonary function during colonoscopy with conscious sedation
Authors: Kim Young Hoon , Kim Ji Won , Lee Kook Lae , Joo Sae Kyung , Lee Jaekyung , Koh Seong‐Joon , Kim Byeong Gwan , Park Chan‐Kuk
Published: October 2013

Background and Aim

Conscious sedation of patients with midazolam reduces anxiety and pain and improves colonoscopy success rates. However, it may lead to adverse effects such as hypoxia and hypotension. The present study investigated the effects of midazolam on cardiopulmonary function during colonoscopy with conscious sedation.

Methods

Between January 2011 and September 2011, 126 consecutive patients undergoing colonoscopy were enrolled and divided into two groups: (i) sedation with midazolam (midazolam group, n = 65); and (ii) no sedation (control group, n = 61). Systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), and peripheral oxygen saturation (SpO2), were recorded before, during and after the endoscopic procedure.

Results

In the midazolam group, SBP and DBP decreased more during colonoscopy than in the control group. However, the frequency of a significant change in SBP was similar in both groups. During colonoscopy, HR and SpO2 decreased significantly in the midazolam group compared to those in the control group. SpO2 levels returned to normal after the procedure.

Conclusions

Midazolam induced decreases in SBP, DBP, HR and SpO2 during colonoscopy. Clinically significant changes in SBP, HR, and SpO2, however, were similar in the midazolam and control groups. These results suggest that midazolam has a tolerable effect on cardiopulmonary function and may be safely used during colonoscopy.
Structural reforms and growth in transition
Authors: Babecky Jan , Havranek Tomas
Published: October 2013

The present fiscal difficulties of many countries amplify the call for structural reforms. To provide stylized facts on how reforms worked in the past, we quantitatively review 60 studies estimating the relationship between reforms and growth. These studies examine structural reforms carried out in 26 transition countries around the world. Our results show that an average reform caused substantial costs in the short run, but had strong positive effects on long‐run growth. Reforms focused on external liberalization proved to be more beneficial than others in both the short and long run. The findings hold even after correction for publication bias and misspecifications present in some primary studies.