bluuebunny/crossref_metadata_2025 huggingface dataset:
Novel ionization processes for use in mass spectrometry: ‘Squeezing’ nonvolatile analyte ions from crystals and droplets
Authors: Trimpin Sarah
Published: August 2018

Together with my group and collaborators, I have been fortunate to have had a key role in the discovery of new ionization processes that we developed into new flexible, sensitive, rapid, reliable, and robust ionization technologies and methods for use in mass spectrometry (MS). Our current research is focused on how best to understand, improve, and use these novel ionization processes which convert volatile and nonvolatile compounds from solids or liquids into gas‐phase ions for analysis by MS using e.g. mass‐selected fragmentation and ion mobility spectrometry to provide reproducible, accurate, and improved mass and drift time resolution. In my view, the apex was the discovery of vacuum matrix‐assisted ionization (vMAI) in 2012 on an intermediate pressure matrix‐assisted laser desorption/ionization (MALDI) source without the use of a laser, high voltages, or any other added energy. Only exposure of the matrix:analyte to the sub‐atmospheric pressure of the mass spectrometer was necessary to initiate ionization. These findings were initially rejected by three different scientific journals, with comments related to ‘how can this work?’, ‘where do the charges come from?’, and ‘it is not analytically useful’. Meanwhile, we and others have demonstrated analytical utility without a complete understanding of the mechanism. In reality, MALDI and electrospray ionization are widely used in science and their mechanisms are still controversially discussed despite use and optimization of now 30 years. This Perspective covers the applications and mechanistic aspects of the novel ionization processes for use in MS that guided us in instrument developments, and provides our perspective on how they relate to traditional ionization processes.
Capital buffer and credit‐risk adjustments in Islamic and conventional banks
Authors: Bougatef Khemaies , Korbi Fakhri
Published: August 2018

The main purpose of this article is to empirically investigate the interactions between changes in capital buffer and changes in credit risk, using panel data of Islamic and conventional banks located in the Middle East and North Africa (MENA) region over the period 1999–2016. A negative two‐way relationship between the changes in capital buffer and the changes in credit risk is found for the two types of banks, that is, banks tend to decrease their capital buffers in response to an increase in risk exposure and limit their risky activities in response to an increase in their capital buffers. Dividing our period of study into three subperiods to assess the effect of the last financial crisis 2007–08 on the adjustment process, we point out the negative bidirectional relationship between the changes in capital buffer and the changes in credit risk of the two types of banks is present for the three subperiods except the case of conventional banks during the precrisis period. Moreover, we provide evidence that Islamic banks adjust their capital buffer in response to the changes in credit risk regardless of the existence or not of a deposit insurance scheme. In contrast, the negative two‐way relationship between the changes in capital buffer and the changes in credit risk in conventional banks is found only in countries without deposit insurance schemes.
Effects and mechanisms of betulinic acid on improving EGFR TKI‐resistance of lung cancer cells
Authors: Ko Jiunn‐Liang , Lin Ching‐Hsiung , Chen Heng‐Chung , Hung Wei‐Heng , Chien Peng‐Ju , Chang Hui‐Yi , Wang Bing‐Yen
Published: August 2018

Epidermal growth factor receptor (EGFR) mutations have been identified in approximately 55% of lung cancer patients in Taiwan. Gefitinib (Iressa) and Erlotinib (Tarceva) are the first‐generation targeting drugs to patients with EGFR gene mutants a work by inhibiting tyrosine kinase activity. However, resistance in EGFR‐mutated patients to first‐generation tyrosine kinase inhibitor (TKI) therapy after 8‐11 months of treatment has occurred. Betulinic acid (BetA) is a pentacyclic triterpenoid natural product derived from widespread plants. BetA has been reported to have a cytotoxic effect in several cancers. The purpose of this study is to investigate the effects and mechanisms of BetA on dampening EGFR TKI‐resistance of lung cancer cells. Our study has demonstrated by MTT assay that combining BetA and an EGFR TKI increased the cytotoxicity against EGFR TKI‐resistance lung cancer cells. Based on flow cytometry, combination treatments of BetA with an EGFR TKI enhanced Sub‐G1 accumulation, induced apoptosis and induced mitochondrial membrane potential loss. Using western blotting, BetA and EGFR TKI combined treatments inhibited cell cycle related protein and triggered apoptosis‐ and autophagy‐ related protein expression. Taken together, our data suggests that a target therapy combining BetA with an EGFR TKI improves drug efficacy in EGFR TKI‐resistant lung cancer cells.
Economic Policy and the Provision of Family Planning in Developing Countries
Authors: Harris Kelsey B.
Published: August 2018

Despite some progress, wide gaps remain in the provision of family planning and reproductive health services in developing countries. As governments debate how to provide such services, this commentary considers general economic motivation, what principles are being implemented in practice, and why government policy may not align with what economic analysis suggests. Case studies from three developing countries—Uganda, Haiti, and the Philippines—are presented in an attempt to bridge gaps between economic analysis, current policy, and implementation, and examine whether economic concepts are being considered in current policy responses. Following this preliminary review, all three countries appear to value economic concepts that reinforce the government's role in provision of family planning, but that does not necessarily correlate to effective policy implementation or access to services. More broadly, this consideration of economic policy and the provision of family planning in three developing countries suggests that economic policy can complement rights‐based policy arguments.
A Filtering of Incomplete GNSS Position Time Series with Probabilistic Principal Component Analysis
Authors: Gruszczynski Maciej , Klos Anna , Bogusz Janusz
Published: August 2018

For the first time, we introduced the probabilistic principal component analysis (pPCA) regarding the spatio-temporal filtering of Global Navigation Satellite System (GNSS) position time series to estimate and remove Common Mode Error (CME) without the interpolation of missing values. We used data from the International GNSS Service (IGS) stations which contributed to the latest International Terrestrial Reference Frame (ITRF2014). The efficiency of the proposed algorithm was tested on the simulated incomplete time series, then CME was estimated for a set of 25 stations located in Central Europe. The newly applied pPCA was compared with previously used algorithms, which showed that this method is capable of resolving the problem of proper spatio-temporal filtering of GNSS time series characterized by different observation time span. We showed, that filtering can be carried out with pPCA method when there exist two time series in the dataset having less than 100 common epoch of observations. The 1st Principal Component (PC) explained more than 36% of the total variance represented by time series residuals’ (series with deterministic model removed), what compared to the other PCs variances (less than 8%) means that common signals are significant in GNSS residuals. A clear improvement in the spectral indices of the power-law noise was noticed for the Up component, which is reflected by an average shift towards white noise from - 0.98 to - 0.67 (30%). We observed a significant average reduction in the accuracy of stations’ velocity estimated for filtered residuals by 35, 28 and 69% for the North, East, and Up components, respectively. CME series were also subjected to analysis in the context of environmental mass loading influences of the filtering results. Subtraction of the environmental loading models from GNSS residuals provides to reduction of the estimated CME variance by 20 and 65% for horizontal and vertical components, respectively.
Vertex operator algebras, Higgs branches, and modular differential equations
Authors: Beem Christopher , Rastelli Leonardo
Published: August 2018

Abstract

Every four-dimensional$$ \mathcal{N}=2 $$N=2superconformal field theory comes equipped with an intricate algebraic invariant, the associated vertex operator algebra. The relationships between this invariant and more conventional protected quantities in the same theories have yet to be completely understood. In this work, we aim to characterize the connection between the Higgs branch of the moduli space of vacua (as an algebraic geometric entity) and the associated vertex operator algebra. Ultimately our proposal is simple, but its correctness requires the existence of a number of nontrivial null vectors in the vacuum Verma module of the vertex operator algebra. Of particular interest is one such null vector whose presence suggests that the Schur index of any$$ \mathcal{N}=2 $$N=2SCFT should obey a finite order modular differential equation. By way of the “high temperature” limit of the superconformal index, this allows the Weyl anomaly coefficientato be reinterpreted in terms of the representation theory of the associated vertex operator algebra. We illustrate these ideas in a number of examples including a series of rank-one theories associated with the “Deligne-Cvitanović exceptional series” of simple Lie algebras, several families of Argyres-Douglas theories, an assortment of class$$ \mathcal{S} $$Stheories, and$$ \mathcal{N}=2 $$N=2super Yang-Mills with$$ \mathfrak{s}\mathfrak{u}(n) $$sungauge group for small-to-moderate values ofn.
The M-theory S-matrix from ABJM: beyond 11D supergravity
Authors: Chester Shai M. , Pufu Silviu S. , Yin Xi
Published: August 2018

Abstract

We show that by studying the flat spacetime limit of the Mellin amplitude associated with the four-point correlation function of scalar operators in the stress tensor multiplet of ABJM theory, one can produce the momentum expansion of the M-theory four-graviton S-matrix elements. Using CFT data previously obtained from the supersymmetric localization method, we carry out this procedure explicitly to the second nontrivial order in the momentum expansion, and recover precisely the knownR4contribution to the scattering amplitude of super-gravitons in M-theory in eleven dimensions.
Electroweak logarithms in inclusive cross sections
Authors: Manohar Aneesh V. , Waalewijn Wouter J.
Published: August 2018

Abstract

We develop the framework to perform all-orders resummation of electroweak logarithms of Q/M for inclusive scattering processes at energies Q much above the electroweak scale M. We calculate all ingredients needed at next-to-leading logarithmic (NLL) order and provide an explicit recipe to implement this for 2 → 2 processes. PDF evolution including electroweak corrections, which lead to Sudakov double logarithms, is computed. If only the invariant mass of the final state is measured, all electroweak logarithms can be resummed by the PDF evolution, at least to LL. However, simply identifying a lepton in the final state requires the corresponding fragmentation function and introduces angular dependence through the exchange of soft gauge bosons. Furthermore, we show the importance of polarization effects for gauge bosons, due to the chiral nature of SU(2) — even the gluon distribution in an unpolarized proton becomes polarized at high scales due to electroweak effects. We justify our approach with a factorization analysis, finding that the objects entering the factorization theorem do not need to be SU(2) × U(1) gauge singlets, even though we perform the factorization and resummation in the symmetric phase. We also discuss a range of extensions, including jets and how to calculate the EW logarithms when you are fully exclusive in the central (detector) region and fully inclusive in the forward (beam) regions.
MRI Findings at the Bone-Component Interface in Symptomatic Unicompartmental Knee Arthroplasty and the Relationship to Radiographic Findings
Authors: Kleeblad Laura Jill , Zuiderbaan Hendrik A. , Burge Alissa J. , Amirtharaj Mark J. , Potter Hollis G. , Pearle Andrew D.
Published: August 2018

Background

The most common modes of failure of cemented unicompartmental knee arthroplasty (UKA) designs are aseptic loosening and unexplained pain at short- to mid-term follow-up, which is likely linked to early fixation failure. Determining these modes of failure remains challenging; conventional radiographs are limited for use in assessing radiolucent lines, with only fair sensitivity and specificity for aseptic loosening.

Questions/Purposes

We sought to characterize the bone-component interface of patients with symptomatic cemented medial unicompartmental knee arthroplasty (UKA) using magnetic resonance imaging (MRI) and to determine the relationship between MRI and conventional radiographic findings.

Methods

This retrospective observational study included 55 consecutive patients with symptomatic cemented UKA. All underwent MRI with addition of multiacquisition variable-resonance image combination (MAVRIC) at an average of 17.8 ± 13.9 months after surgery. MRI studies were reviewed by two independent musculoskeletal radiologists. MRI findings at the bone-cement interface were quantified, including bone marrow edema, fibrous membrane, osteolysis, and loosening. Radiographs were reviewed for existence of radiolucent lines. Inter-rater agreement was determined using Cohen's κ statistic.

Results

The vast majority of symptomatic UKA patients demonstrated bone marrow edema pattern (71% and 75%, respectively) and fibrous membrane (69% and 89%, respectively) at the femoral and tibial interface. Excellent and substantial inter-rater agreement was found for the femoral and tibial interface, respectively. Furthermore, MRI findings and radiolucent lines observed on conventional radiographs were poorly correlated.

Conclusion

MRI with the addition of MAVRIC sequences could be a complementary tool for assessing symptomatic UKA and for quantifying appearances at the bone-component interface. This technique showed good reproducibility of analysis of the bone-component interface after cemented UKA. Future studies are necessary to define the bone-component interface of symptomatic and asymptomatic UKA patients.
Corporate choice and individual values: using accounting to align incentives
Authors: Christensen John
Published: August 2018

Corporate choice is expected to reflect rational behavior and yet there is much anecdotal evidence suggesting the opposite. Often the accounting system plays a major part in such stories. Aligning incentives has always been one of the main concerns of the accounting system. Accounting control has been discussed intensively as one of the purposes of the management accounting system. Furthermore, accounting for stewardship has been important to the financial accounting debate. Goal congruency issues are central to this discussion. In particular, conflicting interests have been transparent in the transfer pricing literature. The development of the transfer pricing literature is used to illustrate the development of how the accounting system is a vehicle to align incentives in the organization. In conclusion, it is argued that the accrual accounting system more generally serves the purpose of aligning incentives.
Graph node rank based important keyword detection from Twitter
Authors: Kumar Mukesh , Rehan Palak
Published: August 2018

Social media networks like Twitter, Facebook, WhatsApp etc. are most commonly used medium for sharing news, opinions and to stay in touch with peers. Messages on twitter are limited to 140 characters. This led users to create their own novel syntax in tweets to express more in lesser words. Free writing style, use of URLs, markup syntax, inappropriate punctuations, ungrammatical structures, abbreviations etc. makes it harder to mine useful information from them. For each tweet, we can get an explicit time stamp, the name of the user, the social network the user belongs to, or even the GPS coordinates if the tweet is created with a GPS-enabled mobile device. With these features, Twitter is, in nature, a good resource for detecting and analyzing the real time events happening around the world. By using the speed and coverage of Twitter, we can detect events, a sequence of important keywords being talked, in a timely manner which can be used in different applications like natural calamity relief support, earthquake relief support, product launches, suspicious activity detection etc. The keyword detection process from Twitter can be seen as a two step process: detection of keyword in the raw text form (words as posted by the users) and keyword normalization process (reforming the users’ unstructured words in the complete meaningful English language words). In this paper a keyword detection technique based upon the graph, spanning tree and Page Rank algorithm is proposed. A text normalization technique based upon hybrid approach using Levenshtein distance, demetaphone algorithm and dictionary mapping is proposed to work upon the unstructured keywords as produced by the proposed keyword detector. The proposed normalization technique is validated using the standard lexnorm 1.2 dataset. The proposed system is used to detect the keywords from Twiter text being posted at real time. The detected and normalized keywords are further validated from the search engine results at later time for detection of events.
Endogenous Testosterone Levels and Cardiovascular Risk: Meta-Analysis of Observational Studies
Authors: Corona Giovanni , Rastrelli Giulia , Di Pasquale Giuseppe , Sforza Alessandra , Mannucci Edoardo , Maggi Mario
Published: August 2018

Introduction

The relationship between endogenous testosterone (T) levels and cardiovascular (CV) risk in men is conflicting.

Aim

To verify whether endogenous T levels represent a possible risk factor for CV morbidity and mortality.

Methods

We conducted a random effect meta-analysis considering all the available data from prospective observational studies comparing subjects with baseline reduced endogenous T levels to those with higher T levels as derived from an extensive MEDLINE, Embase, and Cochrane search. The identification of relevant studies was performed independently by 2 of the authors (G.R. and G.C.), and conflicts resolved by the third investigator (M.M.).

Main Outcome Measures

CV mortality and morbidity were investigated.

Results

After screening, 37 observational studies, published between 1988 and 2017 including 43,041 subjects with a mean age of 63.5 years and mean follow-up of 333 weeks, were considered. Low endogenous T at enrollment predicted overall and CV mortality, as well as CV morbidity, when both unadjusted and fully adjusted models were considered (odds ratio = 1.26 [CI, 1.17; 1.36], 1.54 [CI, 1.25; 1.89], and 1.17 [CI, 1.01; 1.36]; all P < .05 when overall mortality, CV mortality, and CV incidence and fully adjusted models were considered, respectively). The data were confirmed even when nonpopulation–based studies were excluded from the analysis. Metaregression analysis applied to the fully adjusted model showed that the risk of CV mortality was inversely related to mean age at enrollment (S = –0.014 [–0.017;–0.010] and I = 1.073 [0.806;1.339]; both P < .0001) and directly related to the prevalence of diabetes and to the proportion of active smokers.

Clinical Implications

Low endogenous T levels in aging men can represent a possible CV risk factor.

Strengths & Limitations

The present data demonstrated, for the first time, that low T predicts not only CV mortality but also CV morbidity. Data derived from studies reporting information on CV mortality suggested major publication bias although they were confirmed applying Duval and Tweedie trim and fill method. However, observational studies should be considered with caution due to the lack of complete follow-ups and due to the poor management of missing data.

Conclusion

The present meta-analysis shows that low T in aging men is a marker of CV risk. The possible benefits of T treatment in reducing this risk should be examined in longer-term, specifically designed trials.
Vibrations of a square cylinder submerged in a wake
Authors: Bhatt Rajesh , Alam Md. Mahbub
Published: August 2018

A numerical investigation is conducted on the flow around and vibration response of an elastic square cylinder (side width $D$) in the wake of a stationary cylinder at Reynolds numbers of $Re=100$ and 200 based on $D$ and the free-stream velocity. The downstream cylinder, referred to as the wake cylinder, is allowed to vibrate in the transverse direction only. The reduced velocity $U_{r}$ is varied from 1 to 30. Cylinder centre-to-centre spacing ratios of $L^{\ast }(=L/D)=2$ and 6 are considered. Simulations are also conducted for a single isolated cylinder, and the results are compared with those for the wake cylinder. The focus is given to vibration response, frequency response, fluctuating lift force, phase relationship between the lift and displacement, work done and the flow structure modification during the cylinder vibration. The results reveal that the dependence of the Strouhal number $St$ on $U_{r}$ can distinguish different branches more appropriately than that of the vibration amplitude on $U_{r}$. The vibration response of the single cylinder at $Re=100$ is characterized by the initial, lower and desynchronization branches. On the other hand, that at $Re=200$ undergoes initial, lower and galloping branches. The galloping involves the characteristics of both the initial and the lower branches or the initial and the desynchronization branches depending on $U_{r}$. For the wake cylinder, the gap flow has a significant impact on the vibration response, leading to (i) the absence of galloping at either $Re$ and $L^{\ast }$, (ii) the presence of an upper branch at $Re=200$, $L^{\ast }=6$ and (iii) an initial branch of different characteristics at $Re=100$, $L^{\ast }=6$. The different facets are discussed in terms of wake structures, work done and phase lag between lift and displacement.
Approximate solutions to droplet dynamics in Hele-Shaw flows
Authors: Green Yoav
Published: August 2018

For the past decade, the interaction force between droplets flowing in a Hele-Shaw cell has been modelled as a dipole. In this work, we use the recently derived analytical solution of Sariget al.(J. Fluid Mech., vol. 800, 2016, pp. 264–277) of a two-droplet system, which satisfies the no-flux condition at both droplet interfaces, and compare it to results of the dipole model, which does not satisfy the no-flux condition. Unfortunately, the recently derived solution is given in terms of infinite Fourier series, making any additional straightforward analysis difficult. We derive simple approximations for these Fourier series. We show that at large spacing the approximations for the interactions reduce to the expected dipole-like solution. We also provide a new lower limit for the velocity for the case of almost touching droplets. For the case of large spacing, the derivation is extended to arbitrary droplet numbers – including an infinite lattice. We present a new correction for the dispersion relation for the perturbations. We investigate the effect of the number of droplets in a lattice,$N$, on the resulting dynamics.
On the over-production of turbulence beneath surface waves in Reynolds-averaged Navier–Stokes models
Authors: Larsen Bjarke Eltard , Fuhrman David R.
Published: August 2018

In previous computational fluid dynamics studies of breaking waves, there has been a marked tendency to severely over-estimate turbulence levels, both pre- and post-breaking. This problem is most likely related to the previously described (though not sufficiently well recognized) conditional instability of widely used turbulence models when used to close Reynolds-averaged Navier–Stokes (RANS) equations in regions of nearly potential flow with finite strain, resulting in exponential growth of the turbulent kinetic energy and eddy viscosity. While this problem has been known for nearly 20 years, a suitable and fundamentally sound solution has yet to be developed. In this work it is demonstrated that virtually all commonly used two-equation turbulence closure models are unconditionally, rather than conditionally, unstable in such regions. A new formulation of the $k$–$\unicode[STIX]{x1D714}$ closure is developed which elegantly stabilizes the model in nearly potential flow regions, with modifications remaining passive in sheared flow regions, thus solving this long-standing problem. Computed results involving non-breaking waves demonstrate that the new stabilized closure enables nearly constant form wave propagation over long durations, avoiding the exponential growth of the eddy viscosity and inevitable wave decay exhibited by standard closures. Additional applications on breaking waves demonstrate that the new stabilized model avoids the unphysical generation of pre-breaking turbulence which widely plagues existing closures. The new model is demonstrated to be capable of predicting accurate pre- and post-breaking surface elevations, as well as turbulence and undertow velocity profiles, especially during transition from pre-breaking to the outer surf zone. Results in the inner surf zone are similar to standard closures. Similar methods for formally stabilizing other widely used closure models ($k$–$\unicode[STIX]{x1D714}$ and $k$–$\unicode[STIX]{x1D700}$ variants) are likewise developed, and it is recommended that these be utilized in future RANS simulations of surface waves. (In the above $k$ is the turbulent kinetic energy density, $\unicode[STIX]{x1D714}$ is the specific dissipation rate, and $\unicode[STIX]{x1D700}$ is the dissipation.)
Spatio-temporal intermittency of the turbulent energy cascade
Authors: Yasuda T. , Vassilicos J. C.
Published: August 2018

In incompressible and periodic statistically stationary turbulence, exchanges of turbulent energy across scales and space are characterised by very intense and intermittent spatio-temporal fluctuations around zero of the time-derivative term, the spatial turbulent transport of fluctuating energy and the pressure–velocity term. These fluctuations are correlated with each other and with the intense intermittent fluctuations of the interscale energy transfer rate. These correlations are caused by the sweeping effect, the link between nonlinearity and non-locality, and also relate to geometrical alignments between the two-point fluctuating pressure force difference and the two-point fluctuating velocity difference in the case of the correlation between the interscale transfer rate and the pressure–velocity term. All these processes are absent from the spatio-temporal-average picture of the turbulence cascade in statistically stationary and homogeneous turbulence.
Turbulent channel flow of an elastoviscoplastic fluid
Authors: Rosti Marco E. , Izbassarov Daulet , Tammisola Outi , Hormozi Sarah , Brandt Luca
Published: August 2018

We present numerical simulations of laminar and turbulent channel flow of an elastoviscoplastic fluid. The non-Newtonian flow is simulated by solving the full incompressible Navier–Stokes equations coupled with the evolution equation for the elastoviscoplastic stress tensor. The laminar simulations are carried out for a wide range of Reynolds numbers, Bingham numbers and ratios of the fluid and total viscosity, while the turbulent flow simulations are performed at a fixed bulk Reynolds number equal to 2800 and weak elasticity. We show that in the laminar flow regime the friction factor increases monotonically with the Bingham number (yield stress) and decreases with the viscosity ratio, while in the turbulent regime the friction factor is almost independent of the viscosity ratio and decreases with the Bingham number, until the flow eventually returns to a fully laminar condition for large enough yield stresses. Three main regimes are found in the turbulent case, depending on the Bingham number: for low values, the friction Reynolds number and the turbulent flow statistics only slightly differ from those of a Newtonian fluid; for intermediate values of the Bingham number, the fluctuations increase and the inertial equilibrium range is lost. Finally, for higher values the flow completely laminarizes. These different behaviours are associated with a progressive increases of the volume where the fluid is not yielded, growing from the centreline towards the walls as the Bingham number increases. The unyielded region interacts with the near-wall structures, forming preferentially above the high-speed streaks. In particular, the near-wall streaks and the associated quasi-streamwise vortices are strongly enhanced in an highly elastoviscoplastic fluid and the flow becomes more correlated in the streamwise direction.
Core-pressure alleviation for a wall-normal vortex by active flow control
Authors: Liu Qiong , An Byungjin , Nohmi Motohiko , Obuchi Masashi , Taira Kunihiko
Published: August 2018

We consider the application of active flow control to modify the radial pressure distribution of a single-phase wall-normal vortex. The present flow is based on the Burgers vortex model but with a no-slip boundary condition prescribed along its symmetry plane. The wall-normal vortex serves as a model for vortices that emerge upstream of turbomachinery, such as pumps. This study characterizes the baseline vortex unsteadiness through numerical simulation and dynamic mode decomposition. The insights gained from the baseline flow are used to develop an active flow control technique with rotating zero-net-mass blowing and suction with the objective of modifying the core-pressure distribution. The effectiveness of the control strategy is demonstrated by achieving a widened vortex core with increased pressure. This change in the flow field weakens the local strength of the wall-normal vortex core, potentially inhibiting the formation of hollow-core vortices, commonly encountered in liquids.
Hippocampal sclerosis induced in mice by a Taenia crassiceps metacestode factor
Authors: Zepeda N. , Copitin N. , Chávez J.L. , García F. , Jaimes-Miranda F. , Rincón-Heredia R. , Paredes R. , Solano S. , Fernández A.M. , Molinari J.L.
Published: August 2018

An experimental Taenia crassiceps mouse model was used to assess the role of Taenia solium metacestode factor (Fac) in human neurocysticercosis. Intraperitoneal infection with T. crassiceps metacestodes or subcutaneous inoculation with a T. crassiceps metacestode factor (Fac) produced significant impairment of performance (learning) in the Barnes maze and induced bilateral hippocampal sclerosis in mice. Several staining techniques revealed important cell dispersion, extensive apoptosis and cell loss in the dentate gyrus, hilus and CA1-CA3 regions of both hippocampi, as well as intense deterioration of the adjacent cortex. An outstanding disruption of its histoarchitecture in the surrounding tissue of all these regions and apoptosis of the endothelial cells were also observed.
Roman Studies and Digital Resources
Authors: Bagnall Roger S. , Heath Sebastian
Published: August 2018

There is hardly any aspect of scholarly work and teaching in Roman Studies today not marked by digital technology. We assume that readers regularly access digital images of Roman material culture, use digitised corpora of primary sources in the original language or translation or consult online books and articles. The availability of digital resources on the internet is also a welcome enabler of ongoing public interest and even participation in the field. This overall state of affairs is generally a positive development, but both general trends and specific digital resources deserve a critical appraisal.
Expected background rates of latent TB infection in London inner city schools: lessons from a TB contact investigation exercise in a secondary school
Authors: Anaraki S. , Bell A.J. , Perkins S. , Murphy S. , Dart S. , Anderson C.
Published: August 2018

Following an extensive contact tracing exercise at a school in a London borough with one of highest tuberculosis (TB) rates in England, we estimated the background prevalence of latent TB infection to be significantly less than the widely accepted 10%. We screened 271 pupils aged 14–15 years in two groups: 96 pupils in group 1 had significant exposure (>8 h/week in the same room) to a case of infectious TB and 175 in group 2 who had minimal exposure. In group 1, 26% were diagnosed with latent or active TB, compared to 6.3% in group 2. Risk factors for TB infection (e.g. previous exposure or link to high-prevalence communities) were analysed using a cohort study design. In the univariable analysis only being in contact group 1 was statistically significantly associated with being a case (OR 5.25, 95%,P< 0.001). In the multivariable model contact group 1 remained significantly associated with being a case (adjusted OR 4.40,P= 0.001). We concluded that the 6.3% yield of TB infection in contact group 2 is either similar to or higher than the background prevalence rate of latent TB infection (LTBI) in this high TB prevalence London borough. Other parts of England with lower TB prevalence are likely to have even lower LTBI rates.
Translating the Intention to Seek Treatment into Action: Does Symptom Monitoring Make a Difference? Results from a Randomized Controlled Trial
Authors: Shafran R. , Gyani A. , Rostron J. , Allen S. , Myles-Hooton P. , Allcott-Watson H. , Rose S.
Published: August 2018

Background: Most people with common mental health problems do not seek evidence-based psychological interventions. Aims: The aim of this study was to investigate whether monitoring symptoms of depression and anxiety using an app increased treatment-seeking. Method: Three hundred and six people with significant levels of anxiety and depression, none of whom were currently receiving treatment, were randomly allocated to receive either (a) information about local psychological services only, (b) information plus regular symptom monitoring (every 6 days), or (c) information plus open symptom monitoring (monitoring when they felt like it). An app was used to provide information and monitor mood. Results: The proportion of participants who reported receiving treatment after starting the study was 7.2% (10/138) in the information only group, 8.1% (9/111) in the information plus regular monitoring group and 15.8% (9/57) in the information plus open monitoring group. There was a trend for participants who were able to monitor whenever they wished to be more likely to report receiving treatment than people who were only given information about their local treatment services. The impact of the intervention was greatest among participants who intended to seek treatment before taking part. Limitations were that only a small minority of those who downloaded the app completed the study and that the study relied on self-reported measures of treatment-seeking. Conclusions: Symptom monitoring can increase actual treatment-seeking in those with an intention to seek treatment.
Neglected Radio Blackout Induced by the Nonionized Airflow Sheath Around a Supersonic Aircraft
Authors: Gong S. H. , Zhao H. , Hou M. Y. , Li R. X.
Published: August 2018

The characteristics of the flow field around a supersonic aircraft are discussed. It is analyzed that there are interfaces between two adjacent regions with jump change of refractive index in the supersonic flow. The physical mechanism of the Fresnel reflection of an electromagnetic wave at the interfaces mentioned above is analyzed according to the Fresnel reflection phenomenon in the Earth atmosphere. The conditions for the Fresnel reflection in the supersonic flow field are discussed, and the formulae for calculating the Fresnel reflection coefficient are given. According to the process of a radio wave propagating across the interfaces in the supersonic flow field, the other radio blackout phenomenon is proposed for the first time, which is induced by the nonionized atmospheric sheath around a supersonic aircraft, and may be well neglected or mistaken for the plasma‐sheath‐caused radio blackout. The conditions of the nonionized‐atmospheric‐sheath‐induced radio blackout are investigated. The calculation results show that the neglected radio blackout is confined to a rather specific case, a very small range of grazing angles. However, it is significant for identifying the mechanism of radio blackout.
Contrasting Intraseasonal Variations of the Equatorial Pacific Ocean Between the 1997–1998 and 2015–2016 El Niño Events
Authors: Lyu Yilong , Li Yuanlong , Tang Xiaohui , Wang Fan , Wang Jianing
Published: August 2018

Oceanic intraseasonal variability (ISV) plays a vital role in the initiation and development of El Niño events. Mooring observations reveal contrasting characteristics of upper‐ocean zonal current ISV during different El Niño events. Compared to the 1997–1998 event, ISV of the 2015–2016 event was significantly weaker (by around 30–50%) over the equatorial Pacific basin, and the variability maximum was shifted to the east (~160°E). These differences can be largely explained by wind forcing features. ISV of surface winds in 2015 is overall weaker than in 1997. Intraseasonal westerly wind bursts in 1997 occurred near the western boundary and originated from the Indian Ocean, whereas in 2015, perturbations were mainly propagated from the northeast Pacific and achieved the peak power at ~160°E of the equator. These changes are likely associated with the decadal warming of the northeast subtropical Pacific and weakening of the Indian Ocean intraseasonal oscillation.
The Ion/Electron Temperature Characteristics of Polar Cap Classical and Hot Patches and Their Influence on Ion Upflow
Authors: Ma Yu‐Zhang , Zhang Qing‐He , Xing Zan‐Yang , Heelis Roderick A. , Oksavik Kjellmar , Wang Yong
Published: August 2018

The term of “polar cap hot patch” is a newly identified high‐density plasma irregularity at high latitudes, which is associated with high electron temperature and particle precipitation, while a classical polar cap patch has lower electron temperature. To investigate characteristics of hot patches versus classical patches, five years of in situ database of plasma observations from the DMSP satellites was analyzed. For the first time, we show how the ion/electron temperature ratio (or temperature difference) can be used to distinguish between classical and hot patches. For classical patches (Ti/Te > 0.8 or Te < Ti + 600 K), the vertical ion flux is generally downward. For hot patches (Ti/Te < 0.8 or Te > Ti + 600 K), the vertical ion flux is generally upward. The highest upflow occurrence was found near the polar cap boundary, associated with hot patches, particle precipitation, strong convection speed, and localized field‐aligned currents. This result shows that the polar cap hot patches may play a very important role in solar wind‐magnetosphere‐ionosphere coupling processes.
Active Faulting Geometry and Stress Pattern Near Complex Strike‐Slip Systems Along the Maghreb Region: Constraints on Active Convergence in the Western Mediterranean
Authors: Soumaya Abdelkader , Ben Ayed Noureddine , Rajabi Mojtaba , Meghraoui Mustapha , Delvaux Damien , Kadri Ali , Ziegler Moritz , Maouche Said , Braham Ahmed
Published: August 2018

The Maghreb region (from Tunisia to Gibraltar) is a key area in the western Mediterranean to study the active tectonics and stress pattern across the Africa‐Eurasia convergent plate boundary. In the present study, we compile comprehensive data set of well‐constrained crustal stress indicators (from single focal mechanism solutions, formal inversion of focal mechanism solutions, and young geologic fault slip data) based on our and published data analyses. Stress inversion of focal mechanisms reveals a first‐order transpression‐compatible stress field and a second‐order spatial variation of tectonic regime across the Maghreb region, with a relatively stable SHmax orientation from east to west. Therefore, the present‐day active contraction of the western Africa‐Eurasia plate boundary is accommodated by (1) E‐W strike‐slip faulting with reverse component along the Eastern Tell and Saharan‐Tunisian Atlas, (2) a predominantly NE trending thrust faulting with strike‐slip component in the Western Tell part, and (3) a conjugate strike‐slip faulting regime with normal component in the Alboran/Rif domain. This spatial variation of the present‐day stress field and faulting regime is relatively in agreement with the inferred stress information from neotectonic features. According to existing and newly proposed structural models, we highlight the role of main geometrically complex shear zones in the present‐day stress pattern of the Maghreb region. Then, different geometries of these major inherited strike‐slip faults and its related fractures (V‐shaped conjugate fractures, horsetail splays faults, and Riedel fractures) impose their component on the second‐ and third‐order stress regimes. Neotectonic and smoothed present‐day stress map (mean SHmax orientation) reveal that plate boundary forces acting on the Africa‐Eurasia collisional plates control the long wavelength of the stress field pattern in the Maghreb. The current tectonic deformations and the upper crustal stress field in the study area are governed by the interplay of the oblique plate convergence (i.e., Africa‐Eurasia), lithosphere‐mantle interaction, and preexisting tectonic weakness zones.
Overexpression of TFF3 is involved in prostate carcinogenesis via blocking mitochondria-mediated apoptosis
Authors: Liu Jieying , Kim So Youn , Shin Sun , Jung Seung-Hyun , Yim Seon-Hee , Lee Ji Youl , Lee Sug-Hyung , Chung Yeun-Jun
Published: August 2018

The overexpression of trefoil factor family 3 (TFF3) is observed in a variety of cancers, including prostate cancer (PCa), and its potential role in carcinogenesis, such as activating the PI3K/AKT pathway, is suggested. However, its role and its related mechanisms in prostate tumorigenesis remain unknown. To elucidate the role of TFF3 overexpression in PCa, we silenced TFF3 in two PCa cell lines that overexpressed TFF3 and explored the molecular mechanism behind its antiapoptotic role. We also examined TFF3 expression in 108 Korean PCa specimens and 106 normal prostate tissues by immunohistochemistry (IHC) analysis. The mean TFF3 IHC score in the tumor tissues was significantly higher than that in the normal tissues (4.702 vs. 0.311, P = 2.52 × 10-24). TFF3-silenced cells showed suppressed tumor cell growth and migration. TFF3 silencing decreased BCL2 and increased BAX expression. The translocation of BAX to the mitochondria was also confirmed. After TFF3 silencing, the expression of the mitochondrial proapoptotic proteins, cytochrome C and Smac/DIABLO, was elevated, and these proteins were released from the mitochondria to the cytosol. Downstream mediators of mitochondrial apoptosis, including cleaved caspase-3, caspase-9, and PARP, were also elevated. Accordingly, the proportion of apoptotic cells was significantly higher among TFF3-silenced cells. There was no difference in extrinsic apoptosis-related molecules after TFF3 silencing. All the results support that TFF3 silencing induces the downstream signaling pathway of mitochondria-mediated apoptosis. This study provides a better understanding of the mechanism of prostate tumorigenesis, suggesting TFF3 as a potential biomarker and therapeutic target of PCa.
Novel HDAC5-interacting motifs of Tbx3 are essential for the suppression of E-cadherin expression and for the promotion of metastasis in hepatocellular carcinoma
Authors: Dong Liang , Dong Qi , Chen Ying , Li Yichen , Zhang Bao , Zhou Fanghang , Lyu Xiaoming , Chen George G. , Lai Paul , Kung Hsiang-fu , He Ming-Liang
Published: August 2018

Tbx3, a transcriptional repressor, is essential in the organogenesis of vertebrates, stem cell self-renewal and differentiation, and the carcinogenesis of multiple tumor types. However, the mechanism by which Tbx3 participates in the metastasis of hepatocellular carcinoma (HCC) remains largely unknown. In this study, we show that Tbx3 was dramatically upregulated in clinical HCC samples and that elevated expression of Tbx3 promoted cancer progression. To determine the underlying mechanism, systematic glycine scan mutagenesis and deletion assays were performed. We identified two critical motifs, 585LFSYPYT591 and 604HRH606, that contribute to the repression of transcriptional activity. These motifs are also essential for Tbx3 to promote cell migration and metastasis both in vitro and in vivo via the suppression of E-cadherin expression. More importantly, Tbx3 directly interacts with HDAC5 via these motifs, and an HDAC inhibitor blocks Tbx3-mediated cell migration and the downregulation of E-cadherin in HCC. As Tbx3 is involved in the carcinogenesis of multiple types of human cancers, our findings suggest an important target for anti-cancer drug development.
Extreme amyloid polymorphism in Staphylococcus aureus virulent PSMα peptides
Authors: Salinas Nir , Colletier Jacques-Philippe , Moshe Asher , Landau Meytal
Published: August 2018

Members of theStaphylococcus aureusphenol-soluble modulin (PSM) peptide family are secreted as functional amyloids that serve diverse roles in pathogenicity and may be present as full-length peptides or as naturally occurring truncations. We recently showed that the activity of PSMα3, the most toxic member, stems from the formation of cross-α fibrils, which are at variance with the cross-β fibrils linked with eukaryotic amyloid pathologies. Here, we show that PSMα1 and PSMα4, involved in biofilm structuring, form canonical cross-β amyloid fibrils wherein β-sheets tightly mate through steric zipper interfaces, conferring high stability. Contrastingly, a truncated PSMα3 has antibacterial activity, forms reversible fibrils, and reveals two polymorphic and atypical β-rich fibril architectures. These architectures are radically different from both the cross-α fibrils formed by full-length PSMα3, and from the canonical cross-β fibrils. Our results point to structural plasticity being at the basis of the functional diversity exhibited byS. aureusPSMαs.
Overexpressing lncRNA LAIR increases grain yield and regulates neighbouring gene cluster expression in rice
Authors: Wang Ying , Luo Xiaojin , Sun Fan , Hu Jianhua , Zha Xiaojun , Su Wei , Yang Jinshui
Published: August 2018

Long noncoding RNAs (lncRNAs) are essential regulators of gene expression in eukaryotes. Despite increasing knowledge on the function of lncRNAs, little is known about their effects on crop yield. Here, we identify a lncRNA transcribed from the antisense strand of neighbouring gene LRK (leucine-rich repeat receptor kinase) cluster named LAIR (LRK Antisense Intergenic RNA). LAIR overexpression increases rice grain yield and upregulates the expression of several LRK genes. Additionally, chromatin immunoprecipitation assay results indicate H3K4me3 and H4K16ac are significantly enriched at the activated LRK1 genomic region. LAIR binds histone modification proteins OsMOF and OsWDR5 in rice cells, which are enriched in LRK1 gene region. Moreover, LAIR is demonstrated to bind 5′ and 3′ untranslated regions of LRK1 gene. Overall, this study reveals the role of lncRNA LAIR in regulating rice grain yield and lncRNAs may be useful targets for crop breeding.