bluuebunny/crossref_metadata_2025 huggingface dataset:
A pulsed electrolyte cathode discharge used for metal element analysis by atomic emission spectrometry
Authors: Yuan Hao , Yang De-Zheng , Li Xiao , Zhang Li , Zhou Xiong-Feng , Wang Wen-Chun , Xu Yong
Published: May 2019

In this paper, a pulsed electrolyte cathode discharge is generated for the purpose of detecting metal elements by atomic emission spectrometry in atmospheric air. The discharge image, and the waveforms of voltage and current are obtained for studying the discharge mode. To understand the mechanisms of metal atomic excitation, the plasma temperature and the electron density of discharge are obtained by the spectra of N2 (C-B, Δν = −2) and Hβ (486.1 nm), respectively. Also, the effects of the solution pH, solution flow rate, discharge gap, and discharge voltage on the emission intensities of Cu and Fe are discussed to acquire the optimal experimental conditions. It is found that the pulsed electrolyte cathode discharge is a kind of atmospheric pressure glow discharge, and it can analyze metal elements accurately and sensitively. The gas temperature and electron density play important roles in the improvement of emission intensities of metal elements.
Calibration of the Flory-Huggins interaction parameter in field-theoretic simulations
Authors: Beardsley T. M. , Matsen M. W.
Published: May 2019

Field-theoretic simulations (FTS) offer a versatile method of dealing with complicated block copolymer systems, but unfortunately they struggle to cope with the level of fluctuations typical of experiments. Although the main obstacle, an ultraviolet divergence, can be removed by renormalizing the Flory-Huggins χ parameter, this only works for unrealistically large invariant polymerization indexes, N¯. Here, we circumvent the problem by applying the Morse calibration, where a nonlinear relationship between the bare χb used in FTS and the effective χ corresponding to the standard Gaussian-chain model is obtained by matching the disordered-state structure function, S(k), of symmetric diblock copolymers to renormalized one-loop predictions. This calibration brings the order-disorder transition obtained from FTS into agreement with the universal results of particle-based simulations for values of N¯ characteristic of the experiment. In the limit of weak interactions, the calibration reduces to a linear approximation, χ ≈ z∞χb, consistent with the previous renormalization of χ for large N¯.
Observation of multichannel quantum coherent transport and electron-electron interaction in Bi2Te3 single crystal
Authors: Lakhani Archana , Kumar Devendra
Published: May 2019

The bulk of topological insulators is relatively unexplored, due to the excess contribution of conduction from native defects. Here, we investigate the bulk conduction in a Bi2Te3 crystal having a reduced number of defect states. Our results reveal the presence of three transport regimes which are dominated by thermal activation across the bulk band gap, defect state charge conduction, and quantum coherent transport. The low temperature conductance and magnetoconductance reveal the presence of multichannel two-dimensional quantum coherent transport in the bulk. The number of channels is of the order of quintuple layers, signifying each quintuple layer as a single transport channel. These transport channels exhibit a two-dimensional electron-electron interaction effect causing electron dephasing, whereas the conduction from defect states exhibits a three-dimensional electron-electron interaction effect.
Effect of deposition mechanisms on the infrared photoluminescence of erbium-ytterbium silicate films under different sputtering methods
Authors: Zhou P. Q. , Wang X. J. , He Y. D. , Wu Z. F. , Du J. L. , Fu E. G.
Published: May 2019

Three sputtering methods, co-sputtering, multilayer alternate-sputtering, and mixed-target sputtering, have been mainly utilized for depositing erbium–ytterbium silicate films. The deposition mechanisms of different sputtering methods are studied to analyze and optimize the infrared photoluminescence of the erbium–ytterbium silicate films. About two orders of magnitude photoluminescence intensity improvements were obtained in the co-sputtered, alternate-sputtered films, and mixed-target sputtering methods with the optimum Er:Yb ratio of 1:5. Then, the mixed-target sputtered films can have the strongest photoluminescence intensity, with the best crystalline qualities. This is about 2–4 times higher than photoluminescence intensity of the other two sputtering methods. The results not only provide foundation and guidance for the erbium–ytterbium silicate light-source devices preparation, but also indicate the great prospects for applications of erbium–ytterbium silicate films in scale-integrated light sources.
Partial differential equation modeling of rumor propagation in complex networks with higher order of organization
Authors: Zhu Linhe , Zhao Hongyong , Wang Haiyan
Published: May 2019

Mathematical modeling is an important approach to research rumor propagation in online social networks. Most of prior work about rumor propagation either carried out empirical studies or focus on ordinary differential equation models with only consideration of temporal dimension; little attempt has been given on understanding rumor propagation over both temporal and spatial dimensions. This paper primarily addresses an issue related to how to define a spatial distance in online social networks by clustering and then proposes a partial differential equation model with a time delay to describing rumor propagation over both temporal and spatial dimensions. Theoretical analysis reveals the existence of equilibrium points, a priori bound of the solution, the local stability and the global stability of equilibrium points of our rumor propagation model. Finally, numerical simulations have analyzed the possible influence factors on rumor propagation and proved the validity of the theoretical analysis.
Common-path, single-shot phase-shifting digital holographic microscopy using a Ronchi ruling
Authors: S. Yaghoubi S. Hossein , Ebrahimi Samira , Dashtdar Masoomeh , Doblas Ana , Javidi Bahram
Published: May 2019

Phase-shifting digital holography is widely considered to be a groundbreaking method to quantitatively investigate the phase distribution of specimens, such as living cells. The main flaws of this method, however, are that the requirement for several sequential phase-shifted holograms eliminates the possibility of single-shot imaging and complex configurations would also increase the temporal noise. The present paper aims to validate a single-shot, common-path, phase-shifting digital holographic microscopy, employing a self-referencing geometry. A Ronchi ruling, located in the Fourier plane of a standard microscopic imaging system, produces multiple replicas of sample information in the image plane. The phase retrieval algorithm is performed by superposition of the sample-free portion of each replica with the object information, and requires at least three adjacent diffraction orders. To evaluate the performance of the proposed method, the phase distribution of silica microspheres as a test sample and the morphology of red blood cells as a biological specimen are determined. This configuration offers improved temporal stability in comparison with previously reported Mach–Zehnder interferometers, and may serve as an alternative for real-time surveying of nanometric and subnanometric fluctuations of living microscopic specimens.
A τ−1 measurement across three orders of magnitude based on an atomic spin precession magnetometer in self-sustaining mode
Authors: Zhao Q. , Fan B. L. , Wang S. G. , Wang L. J.
Published: May 2019

The absolute measurement of magnetic fields can be realized by monitoring the Larmor precession of atomic spins. Yet, this spin-precession magnetometer can only be put into use in weak magnetic fields and the sensitivity is limited by the coherence time beyond which, the uncertainty decreases as τ−1/2 rate. Now we demonstrate that the dynamic range of an atomic spin magnetometer can be extended to geomagnetic field magnitude with τ−1 property maintained based on the the self-sustaining method. A mean sensitivity of 20 pT/Hz and a frequency response bandwidth of 5 kHz are realized in a magnetic field of 10000 nT. More important applications in large magnetic fields can be enabled in virtue of the superiority using this self-sustaining magnetometer.
A nonlinear energetic particle diffusion model with a variable source
Authors: Litvinenko Yuri E. , Walter Dominik , Fichtner Horst
Published: May 2019

We investigate analytically and numerically the effect of a time-dependent source in a nonlinear model of diffusive particle transport, based on the p-Laplacian equation. The equation has been used to explain the observed cosmic-ray distributions and it appears in fluid dynamics and other areas of applied mathematics. We derive self-similar solutions for a class of the particle source functions and develop approximate analytical solutions, based on an integral method. We also use the fundamental solution to obtain an asymptotic description of an evolving particle density profile, and we use numerical simulations to investigate the accuracy of the analytical approximations.
Hydrophobic metal-organic frameworks: Potential toward emerging
applications
Authors: Mukherjee Soumya , Sharma Shivani , Ghosh Sujit K.
Published: May 2019

Metal-organic frameworks, popularly known as MOFs, have come of age—thanks to custom-built design principles enabling them to serve a myriad of task-specific applications. In an era where >6000 new MOFs are annually published, driven by academic research, a new generation of MOFs that can find use in niche markets is on the rise. One of the foremost challenges that plague the translation of MOFs into materials suited for commercialization is their water-influenced degradation, largely accountable to hydrolytic instability and the ubiquity of water. Hydrophobic MOFs offer one of the most promising solutions which can enable these porous materials to leverage their functionalization guided properties even under extreme humid conditions, a criterion that application-ready materials should necessarily serve. In this contribution, our discussion focuses on the state-of-the-art hydrophobic MOFs and MOF-derived composites. Outlining a brief overview of the structure-property correlation aspects in each of these promising hydrophobic MOFs with little or no influence exhibited to water and/or humidity, a future outlook is put forward to enable potentially better design strategies leading to futuristic MOFs tolerant to water/moisture. Concise premise of this review allows us to limit our discussion to the design principles in action behind the most hydrophobic MOFs/derived composites reported thus far and to discuss their prime applications viz., oil/water separation inclusive of self-cleaning, hydrocarbon separation, and tackling marine oil spillage. When synergized, such improved porous material design approaches lean toward a greener environment of tomorrow.
Ferroelectric imprint and polarization in the amorphous phase in P(VDF-TrFE)
Authors: Peter Christian , Kliem Herbert
Published: May 2019

Poly(vinylidene fluoride-trifluoroethylene) is a ferroelectric copolymer. It is considered a promising candidate for sensors, nonvolatile memory applications, and energy harvesting. However, imprint, a phenomenon associated with ferroelectric polarization, changes reversibly the material properties over time. In particular, imprint results in an increase of the ferroelectric polarization switching time and the coercive field, as well as in the decay of the remanent polarization and the permittivity. We present a concept to explain imprint and present experimental evidence supporting this concept. In this concept, an internal electric field arises as a consequence of the interaction between ferroelectric dipoles and relaxational dipoles present in the crystalline and the amorphous phase, respectively. We use an extended Weiss mean field approach and show that this internal field results in the experimentally observed imprint. In addition, we show that the imprint can be largely suppressed by increasing the copolymer’s crystallinity.
Enthalpic contributions to solvent–solute and solvent–ion interactions: Electronic perturbation as key to the understanding of molecular attraction
Authors: Smiatek Jens
Published: May 2019

We present a theoretical and numerical framework for the study of molecular attraction mechanisms between species in solution. The respective approach provides detailed insight into the enthalpic contributions of solvation and relies on molecular exchange reactions in combination with electronic perturbations. Associated values for chemical reactivity indices such as the electronegativity, the chemical hardness, and the electrophilicity are obtained from straightforward conceptual density functional theory calculations. Further analysis of corresponding reaction energies allows us to estimate the enthalpic stability of solvent–solute, solvent–ion, and ion–ion complexes. The validity of our approach is demonstrated by the calculation of donor numbers for distinct solvents. Our results reveal a reasonable agreement between calculated and experimental outcomes which highlights the applicability of our combined theoretical and computational approach.
Complexity reduction ansatz for systems of interacting orientable agents: Beyond the Kuramoto model
Authors: Chandra Sarthak , Girvan Michelle , Ott Edward
Published: May 2019

Previous results have shown that a large class of complex systems consisting of many interacting heterogeneous phase oscillators exhibit an attracting invariant manifold. This result has enabled reduced analytic system descriptions from which all the long term dynamics of these systems can be calculated. Although very useful, these previous results are limited by the restriction that the individual interacting system components have one-dimensional dynamics, with states described by a single, scalar, angle-like variable (e.g., the Kuramoto model). In this paper, we consider a generalization to an appropriate class of coupled agents with higher-dimensional dynamics. For this generalized class of model systems, we demonstrate that the dynamics again contain an invariant manifold, hence enabling previously inaccessible analysis and improved numerical study, allowing a similar simplified description of these systems. We also discuss examples illustrating the potential utility of our results for a wide range of interesting situations.
Solution-based green amplified spontaneous emission from colloidal perovskite nanocrystals exhibiting high stability
Authors: Tan Max J. H. , Wang Yi , Chan Yinthai
Published: May 2019

Solution-based optical amplification affords a host of benefits ranging from flexibility in the choice of cavity size and shape to high photostability afforded by the constant replenishment of gain media. Works reporting solution-based optical amplification in colloidal semiconductor nanocrystals, however, remain sparse due to the difficulty in achieving high particle number densities required for sustained optical gain. In this work, we demonstrate highly stable amplified spontaneous emission (ASE) from a solution of green-emitting CsPbBr3 perovskite nanocrystals dispersed in a nonpolar solvent after a facile postsynthesis processing step. This processing step not only allows for the purification of nanocrystals from their growth solution, but also allows for long-term colloidal stability at high particle concentrations. Although it is widely reported that perovskite nanocrystals suffer from poor chemical stability, our nanocrystal solutions retain their ASE properties despite long-term storage in excess of five months under ambient conditions. Photostability tests show steady ASE intensities in excess of three hours under constant photoexcitation from a femtosecond pulsed laser beam (>107 shots), far exceeding those of thin films by an order of magnitude. This work opens the possibility of harnessing colloidal CsPbBr3 nanocrystals as highly robust, solution-based optical gain media.
Shear stress relaxation and diffusion in simple liquids by molecular dynamics simulations: Analytic expressions and paths to viscosity
Authors: Heyes D. M. , Smith E. R. , Dini D.
Published: May 2019

The results are reported of an equilibrium molecular dynamics simulation study of the shear viscosity, η, and self-diffusion coefficient, D, of the Lennard-Jones liquid using the Green-Kubo (GK) method. Semiempirical analytic expressions for both GK time correlation functions were fitted to the simulation data and used to derive analytic expressions for the time dependent diffusion coefficient and shear viscosity, and also the correlation function frequency transforms. In the case of the shear viscosity for a state point near the triple point, a sech function was found to fit the correlation function significantly better than a gaussian in the ballistic short time regime. A reformulation of the shear GK formula in terms of a time series of time integrals (“viscuits”) and contributions to the viscosity from components based on the initial stress (“visclets”) enable the GK expressions to be recast in terms of probability distributions which could be used in coarse grained stochastic models of nanoscale flow. The visclet treatment shows that stress relaxation is statistically independent of the initial stress for equilibrium and metastable liquids, suggesting that shear stress relaxation in liquids is diffusion controlled. By contrast, the velocity autocorrelation function is sensitive to the initial velocity. Weak oscillations and a plateau at intermediate times originate to a greater extent from the high velocity tail of the Maxwell-Boltzmann velocity distribution. Simple approximate analytic expressions for the mean square displacement and the self Van Hove correlation function are also derived.
Spectroscopic characterization of metal ligation in trinuclear iron-μ3-oxo-based complexes and metal-organic frameworks
Authors: Hanna Lauren , Kucheryavy Pavel , Lahanas Nicole , Lockard Jenny V.
Published: May 2019

The adsorption-based functionalities of porous metal-organic framework (MOF) materials that lead to applications such as catalysis and gas separation rely on specific host–guest interactions often involving the framework metal sites. These interactions are difficult to probe on the molecular level and consequently poorly understood. Conventional X-ray absorption spectroscopy (XAS) methods can provide molecular-level insights but, as the sole method of characterization, often lack the ligand sensitivity required to probe the relevant local metal coordination changes associated with MOF adsorption processes. Here, we investigate a series of trinuclear iron μ3-oxo-based MOFs under different metal-coordinating guest environments (water, pyridine, propylene, and guest-free) using a multipronged spectroscopy approach, including valence-to-core X-ray emission spectroscopy (vtc-XES) along with conventional XAS and vibrational spectroscopy, in an effort to characterize their local metal site coordination environments, including ligand identity. Closely related iron μ3-oxo reference complexes with known coordination are characterized as well for comparison to evaluate the ligand diagnostic nature of the combined spectroscopy approach. Density functional theory calculations aid the vtc-XES band assignments and provide insights into the molecular orbital parentage of the vtc transitions. This series of MOFs and complexes illustrates the advantages and limitations of using this combination of complementary techniques for distinguishing subtle differences in framework metal node coordination environments.
Controlling chimera states via minimal coupling modification
Authors: Ruzzene Giulia , Omelchenko Iryna , Schöll Eckehard , Zakharova Anna , Andrzejak Ralph G.
Published: May 2019

We propose a method to control chimera states in a ring-shaped network of nonlocally coupled phase oscillators. This method acts exclusively on the network’s connectivity. Using the idea of a pacemaker oscillator, we investigate which is the minimal action needed to control chimeras. We implement the pacemaker choosing one oscillator and making its links unidirectional. Our results show that a pacemaker induces chimeras for parameters and initial conditions for which they do not form spontaneously. Furthermore, the pacemaker attracts the incoherent part of the chimera state, thus controlling its position. Beyond that, we find that these control effects can be achieved with modifications of the network’s connectivity that are less invasive than a pacemaker, namely, the minimal action of just modifying the strength of one connection allows one to control chimeras.
New microwave spectrometer combines speed with sensitivity
Authors: Johnson-Groh Mara
Published: May 2019

A new microwave spectrometer based on cryogenic methods can measure samples up to 3,000 times faster than previous cavity-enhanced instruments.
Inhibition effect of kaolinite on the development of antibiotic resistance genes in Escherichia coli induced by sublethal ampicillin and its molecular mechanism
Authors: Lai Xiaolin , Wu Pingxiao , Ruan Bo , Liu Juan , Liu Zehua , Zhu Nengwu , Dang Zhi
Published: May 2019

Environmental contextAntibiotic resistance by microorganisms in the natural environment poses a threat to ecosystems and public health. We report findings suggesting kaolinite can effectively inhibit the development of antibiotic resistance genes in microorganisms, and present a new understanding of the molecular mechanisms that promote the development of antibiotic resistance. These results are critical to mitigating environmental and public health risks resulting from the abuse of antibiotics. AbstractAntibiotic resistance and antibiotic resistance genes (ARGs) in the natural environment pose a threat to ecosystems and public health; therefore, better strategies are needed to mitigate the emergence of resistance. This study examined the expression of ARGs in Escherichia coli (E. coli) after exposure to sub-MIC (minimum inhibitory concentration) antibiotics for 15 days in the presence and absence of kaolinite. The results of the real-time polymerase chain reaction (PCR) showed that the expression levels of the eight target genes of E. coli adhering to kaolinite were relatively decreased, and the MIC results also indicated that the final resistance was lower than that of the strains without kaolinite. A close relationship between E. coli and kaolinite was also revealed, as well as a unique interfacial interaction. In addition, the differential protein expression was further analysed to detect proteins and genes associated with ARGs mutations, and then the underlying mechanisms of cell growth and metabolism were identified under low dose ampicillin stress to elucidate the role of kaolinite in the process. Molecular mechanisms analysis determined that when cells adhering to kaolinite were stressed, transport of ampicillin to the periplasmic space was reduced, and the redox metabolism of bacteria was promoted to combat the harsh environment. Moreover, cells synthesised related peptides or proteins under the action of ribosomal proteins to prevent toxic damage. Therefore, this work not only provides new insights into the cellular response to antibiotic stress, but also provides a topic for more research on methods to delay the emergence of ARGs.
A randomized control trial evaluating the effects of police body-worn cameras
Authors: Yokum David , Ravishankar Anita , Coppock Alexander
Published: May 2019

Police body-worn cameras (BWCs) have been widely promoted as a technological mechanism to improve policing and the perceived legitimacy of police and legal institutions, yet evidence of their effectiveness is limited. To estimate the effects of BWCs, we conducted a randomized controlled trial involving 2,224 Metropolitan Police Department officers in Washington, DC. Here we show that BWCs have very small and statistically insignificant effects on police use of force and civilian complaints, as well as other policing activities and judicial outcomes. These results suggest we should recalibrate our expectations of BWCs’ ability to induce large-scale behavioral changes in policing, particularly in contexts similar to Washington, DC.
Heat stress directly impairs gut integrity and recruits distinct immune cell populations into the bovine intestine
Authors: Koch Franziska , Thom Ulrike , Albrecht Elke , Weikard Rosemarie , Nolte Wietje , Kuhla Björn , Kuehn Christa
Published: May 2019

Significance

Consequences of heat stress, particularly for the immune system and the intestinal health of mammals, are a topic of increasing global relevance due to rising temperatures and potential health impairments. Specific climate effects, however, are often difficult to discriminate from indirect consequences, e.g. reduced feed intake. Our study in dairy cattle, which are particularly sensitive to heat, identifies the infiltration of the small intestinal epithelium by a previously unobserved distinct cell population with macrophage-like phenotype in response to moderate heat stress. By using a pair-feeding design, we attributed these effects as direct consequences of heat stress via impaired intestinal barrier function. Therefore, an appropriate gut function is an important component in combating the negative consequences of heat stress.
Remodeling of ER–plasma membrane contact sites but not STIM1 phosphorylation inhibits Ca
2+
influx in mitosis
Authors: Yu Fang , Hubrack Satanay Z. , Chakraborty Sumita , Sun Lu , Alcantara-Adap Ethel , Kulkarni Rashmi , Billing Anja M. , Graumann Johannes , Taylor Colin W. , Machaca Khaled
Published: May 2019

Significance

The mechanisms blocking Ca
2+
influx in mitosis are complex and involve a decrease in stable endoplasmic reticulum (ER)–plasma membrane (PM) contact sites and degradation of the ER Ca
2+
sensor stromal interaction molecule 1 (STIM1) but not its phosphorylation. This challenges the current view that STIM1 phosphorylation is essential for mitotic store-operated Ca
2+
entry inhibition and sheds light on the dynamics of ER–PM contact sites and of Ca
2+
influx in mitosis.
Defect engineering of metal–oxide interface for proximity of photooxidation and photoreduction
Authors: Zhou Yangen , Zhang Zizhong , Fang Zhiwei , Qiu Mei , Ling Lan , Long Jinlin , Chen Lu , Tong Yuecong , Su Wenyue , Zhang Yongfan , Wu Jeffrey C. S. , Basset Jean-Marie , Wang Xuxu , Yu Guihua
Published: May 2019

Significance

Oxidation and reduction steps in catalysis are always in series, and excellent activity can be achieved when they occur in close proximity. Photooxidation and photoreduction are generally separated and rarely in series. This work develops defect engineering at the metal–oxide interface to make photooxidation sites close to photoreduction sites. Taking solar hydrogen production from aqueous alcohols over Pt/

T
i
O

2

as an example, the proximity effect triggers unusual reactions and thus increases hydrogen yield per photon from 0.046 to 1.28. Our study provides a direction for the development of efficient photocatalysis.
Chemical evidence for the use of multiple psychotropic plants in a 1,000-year-old ritual bundle from South America
Authors: Miller Melanie J. , Albarracin-Jordan Juan , Moore Christine , Capriles José M.
Published: May 2019

Significance

Humans have a long history of using natural resources, especially plants, to induce nonordinary states of consciousness. Imbibing substances derived from plants have been linked to ancient and elaborate knowledge systems and rituals. While archaeological evidence of the consumption of psychotropics, such as alcohol or caffeine, dates back thousands of years, evidence of the use of other psychoactive substances has been more difficult to document. This article presents the results of chemical analyses of organic residues found in a 1,000-year-old ritual bundle recovered from the highland Andes. The analyses provide evidence of the use of multiple psychoactive plants associated with a sophisticated botanical knowledge system among ritual specialists (shamans) during pre-Columbian times.
Heterogeneity in refractory acute myeloid leukemia
Authors: Horibata Sachi , Gui Gege , Lack Justin , DeStefano Christin B. , Gottesman Michael M. , Hourigan Christopher S.
Published: May 2019

Significance

Acute myeloid leukemia (AML) is the name given to a diverse set of highly fatal blood cancers. The typical initial treatment is combination cytotoxic chemotherapy with at least two drugs: 7 days of cytarabine with 3 days of an anthracycline. As treatment at initial diagnosis is often given emergently, there is a great need for pretreatment markers capable of identifying patients for whom standard treatment is likely to be suboptimal. This work uses RNA-sequencing analysis of a diverse cohort of highly annotated AML patient samples to demonstrate heterogeneity among those patients not responding to standard chemotherapy, then uses this information both to develop a prognostic classifier for survival and to suggest potentially superior therapeutic approaches for those at highest risk.
Wnt canonical pathway activates macropinocytosis and lysosomal degradation of extracellular proteins
Authors: Tejeda-Muñoz Nydia , Albrecht Lauren V. , Bui Maggie H. , De Robertis Edward M.
Published: May 2019

Significance

There is a critical need for new drugs targeting Wnt-driven diseases. For example, 80% of colorectal cancers are initiated by Wnt-activating APC mutations which then require multiple additional mutations to progress into invasive cancer. Here we present cell biological studies showing that Wnt pathway activation, or mutation of the tumor suppressors APC or Axin, greatly increased macropinocytosis. In the presence of Wnt, membrane ruffles at the plasma membrane engulfed large volumes of extracellular fluids which were channeled for degradation in lysosomes. The experiments suggest that inhibition of multivesicular body formation, methylation, or the Na+/H+exchanger, may help prevent Wnt-driven cancer progression.
The DESI Fiber View Camera System
Authors: Baltay C. , Rabinowitz D. , Besuner R. , Casetti D. , Emmet W. , Fagrelius P. , Girard T. , Heetderks H. , Lampton M. , Lathem A. , Levi M. , Padmanabhan N. , Silber J.
Published: May 2019

The Dark Energy Spectroscopic Instrument (DESI) is a 5000 fiber multi-object spectrometer now being installed at the prime focus of the 4 m Mayall telescope at Kitt Peak. Using DESI to measure ∼35 million galaxy redshifts and using the Baryon Acoustic Oscillation (BAO) technique to measure distances, the results will probe the nature of the recently discovered mysterious component of our universe called dark energy. Computer controlled robotic positioners move the 120 μm diameter fibers to positions of galaxies whose location on the sky have been obtained in a previous target selection imaging survey. To achieve good throughput the fibers should be centered on the target position to within 3 μm. The robotic positioners however are only capable of a 50 μm precision on their first move. To achieve the desired precision, the Fiber View Camera (FVC) system has been implemented. The FVC, located near the hole in the primary mirror of the Mayall telescope, has been designed to take an exposure of the focal plane, located at the prime focus some 12 m above the FVC, after the robotic positioners have completed their first move. The FVC is intended to measure the fiber locations with a precision of 3 μm and issue a set of fiber coordinate corrections for the second move correcting the fiber positions by the robotic positioners. Tests show that after two iterations better than 99% of the fibers will be in their intended location to within the desired precision. This paper describes the design of the FVC system, the R&D program preceding the final design, and the tests that have been carried out to demonstrate that the FVC can achieve the required precision.
Myocardial injury after non-cardiac surgery: diagnosis and management
Authors: Devereaux P J , Szczeklik Wojciech
Published: May 2019

Myocardial injury after non-cardiac surgery (MINS) is due to myocardial ischaemia (i.e. supply-demand mismatch or thrombus) and is associated with an increased risk of mortality and major vascular complications at 30 days and up to 2 years after non-cardiac surgery. The diagnostic criteria for MINS includes an elevated post-operative troponin measurement judged as resulting from myocardial ischaemia (i.e. no evidence of a non-ischaemic aetiology), during or within 30 days after non-cardiac surgery, and without the requirement of an ischaemic feature (e.g. ischaemic symptom, ischaemic electrocardiography finding). For patients with MINS who are not at high risk of bleeding, physicians should consider initiating dabigatran 110 mg twice daily and low-dose aspirin. Physicians should also consider initiating statin therapy in patients with MINS. Most MINS patients should only be referred to cardiac catheterization if they demonstrate recurrent instability (e.g. cardiac ischaemia, heart failure). Patients ≥65 years of age or with known atherosclerotic disease should have troponin measurements on days 1, 2, and 3 after surgery while the patient is in hospital to avoid missing >90% of MINS and the opportunity to initiate secondary prophylactic measures and follow-up.
Challenging Unwritten Measures in the World Trade Organization: The Need for Clear Legal Standards
Authors: Valles Cherise , Pogoretskyy Vitaliy , Yanguas Tatiana
Published: May 2019

Disputes in the World Trade Organization (WTO) involving the challenge of unwritten measures have increased in recent years. This trend may have been encouraged by the successful challenge of Argentina’s ‘managed trade policy’ as an ‘overarching unwritten measure’ in Argentina—Import Measures. Advancing a claim against an unwritten measure, however, is not an easy undertaking. These measures are not embodied in any law, administrative regulation or judicial decision. Their very existence and precise contours are, therefore, uncertain and must be proven with evidence, which may not necessarily be readily available. The uncertain nature of unwritten measures makes the dispute settlement process significantly more complicated for the complainant, the respondent and the WTO adjudicators. Despite the difficulties in challenging, defending and adjudicating unwritten measures, relatively little has been written on this subject. This article discusses the types of trade concerns that could be challenged as ‘unwritten measures’, and the different legal characterizations (analytical tools) that have been used to challenge these trade concerns in the WTO. The article further explores the practical difficulties that have been encountered in challenges against unwritten measures and how these difficulties have sometimes, but not always, been overcome. The article concludes that there is a lack of clarity as to the correct legal standard that must be applied in the challenge of different types of unwritten measures. There is more work to be done to clarify the applicable legal standards and the types of evidence required to substantiate the existence of unwritten measures.
De Garengeot’s hernia with appendicitis—a rare cause of an acutely painful groin swelling
Authors: O’Connor Adam , Asaad Peter
Published: May 2019

De Garengeot hernia is a rare subtype of femoral hernia whereby the vermiform appendix is located within the hernial sac. Even rarer is the presence of appendicitis within the hernia sac. De Garengeot’s hernia is difficult to diagnose pre-operatively and can prove technically difficult at operation particularly with regards to mobilization of the caecum and appendix in order to perform appendicectomy. Laparoscopic, open, with and without mesh repair of de Garengeot hernia have all been described in the literature with varying degrees of success. We present a case of an 82 year old lady presenting with an acutely painful right sided groin lump. CT scan revealed the presence of de Garengeot hernia with acute appendicitis. We describe in text and photo format our approach to the hernia repair, appendicectomy and provide a short review of the literature with regards to the different operative approaches to such a patient.
No Clinical Benefit to Treating Male Urinary Tract Infection Longer Than Seven Days: An Outpatient Database Study
Authors: Germanos George J , Trautner Barbara W , Zoorob Roger J , Salemi Jason L , Drekonja Dimitri , Gupta Kalpana , Grigoryan Larissa
Published: May 2019

Background

The optimal approach for treating outpatient male urinary tract infections (UTIs) is unclear. We studied the current management of male UTI in private outpatient clinics, and we evaluated antibiotic choice, treatment duration, and the outcome of recurrence of UTI.

Methods

Visits for all male patients 18 years of age and older during 2011–2015 with International Classification of Diseases, Ninth Revision, Clinical Modification codes for UTI or associated symptoms were extracted from the EPIC Clarity Database of 2 family medicine, 2 urology, and 1 internal medicine clinics. For eligible visits in which an antibiotic was prescribed, we extracted data on the antibiotic used, treatment duration, recurrent UTI episodes, and patient medical and surgical history.

Results

A total of 637 visits were included for 573 unique patients (mean age 53.7 [±16.7 years]). Fluoroquinolones were the most commonly prescribed antibiotics (69.7%), followed by trimethoprim-sulfamethoxazole (21.2%), nitrofurantoin (5.3%), and beta-lactams (3.8%). Antibiotic choice was not associated with UTI recurrence. In the overall cohort, longer treatment duration was not significantly associated with UTI recurrence (odds ratio [OR] = 1.95; 95% confidence interval [CI], 0.91–4.21). Longer treatment was associated with increased recurrence after excluding men with urologic abnormalities, immunocompromising conditions, prostatitis, pyelonephritis, nephrolithiasis, and benign prostatic hyperplasia (OR = 2.62; 95% CI, 1.04–6.61).

Conclusions

Our study adds evidence that men with UTI without evidence of complicating conditions do not need to be treated for longer than 7 days. Shorter duration of treatment was not associated with increased risk of recurrence. Shorter treatment durations for many infections, including UTI, are becoming more attractive to reduce the risk of resistance, adverse events, and costs.
Climate, Ecology and History in North America’s Tallgrass Prairie Borderlands*
Authors: Morrissey Robert Michael
Published: May 2019

In the late 1600s, one of the largest population centres in North America — the so‐called Grand Village of the Kaskaskias in the upper Illinois River Valley — suddenly dissolved as various factions among its indigenous inhabitants split apart. While historians have often explained the resulting migrations as a response to the beginnings of colonial history in this region, this article argues that a greater factor may have been climate change. The region of the Illinois Valley was one of the most important ecological transition zones in North America, a biome-scale ecotone between the grasslands of the West and the woodlands of the East. New studies suggest that a major drought in this period had a drastic effect on the special ecological mosaic here, causing interruptions in dynamic ecosystem processes which likely impacted indigenous ways of life. This article provides not only a better understanding for one of the most consequential turning points in late seventeenth-century North American indigenous history, but also a model of the potential benefits of bringing ethnohistory, deep history, climate history and ecology together in a single cross-disciplinary narrative.
Apremilast increases IL-10-producing regulatory B cells and decreases proinflammatory T cells and innate cells in psoriatic arthritis and psoriasis
Authors: Mavropoulos Athanasios , Zafiriou Efterpi , Simopoulou Theodora , Brotis Alexandros G , Liaskos Christos , Roussaki-Schulze Aggeliki , Katsiari Christina G , Bogdanos Dimitrios P , Sakkas Lazaros I
Published: May 2019

Objectives

Psoriatic arthritis (PsA) and psoriasis are immune-mediated inflammatory diseases sharing common immunological mechanisms. Regulatory B cells (Breg cells) producing IL–10 (B10 cells), a critical anti-inflammatory B-cell subset, were found to be decreased in both PsA and psoriasis. Apremilast, a phosphodiesterase-4(PDE4) inhibitor, increases IL-10 and therefore, we examined the effect of apremilast on Breg cells.

Methods

Fifty patients, including 20 with PsA and 30 with psoriasis, were included in the study. The effect of apremilast on Breg cells at 3, 6 and 12 months post-treatment, was examined by flow cytometry in ODN2006 (TLR9)-stimulated peripheral blood mononuclear cells and magnetically-isolated cells. Th1 cells, Th17 cells and NKT were also measured.

Results

Ex vivo stimulated cell analysis identified that post-apremilast (IL-10+CD19+) B10 cells were increased in all PsA and psoriasis patients and correlated with psoriatic skin and joint clinical improvement. Apremilast decreased IFNγ(+) T and NKT cells and IL-17(+)NKT cells. B10 cells also inversely correlated with Th1 cells, and IFNγ(+)NKT cells.

Conclusion

These results suggest that Breg cells are a major target of apremilast in PsA and psoriasis and that apremilast-induced increase of Breg cells is associated with a decrease of Th1 cells, IFNγ-producing NKT cells and IL-17-producing NKT cells.
DEVElOPMENT OF DOSE ESTIMATION SYSTEM INTEGRATING SEDIMENT MODEL FOR RECYCLING RADIOCESIUM-CONTAMINATED SOIL TO COASTAL RECLAMATION
Authors: Miwa Kazuji , Takeda Seiji , Iimoto Takeshi
Published: May 2019

We have developed a dose estimation system integrating assessment methods of radionuclide dispersion in ocean for the case of recycling radiocesium-contaminated soil to coastal reclamation. Radionuclide dispersion in ocean is assessed considering dissolved radionuclide and adsorbed radionuclide on particle by sediment model (OECD/NEA). Time series of Cs-137 dispersion at Fukushima coastal area is assessed by the sediment model and result is almost same with measured value. The major exposure pathways in recycling are estimated by using result of radiocesium dispersion assessment, and internal exposure dose by marine products ingestion is sufficiently lower than external exposure dose of worker.
Universal and naked-eye gene detection platform based on CRISPR/Cas12a/13a system
Authors: Yuan Chao-Qun , Tian Tian , Sun Jian , Hu Meng-Lu , Wang Xu-Sheng , Xiong Er-Hu , Cheng Meng , Bao Yi-Juan , Lin Wei , Jiang Jie-Ming , Yang Cheng-Wei , Chen Qian , Wang Heng , Wang Xi-Ran , Deng Xian-Bo , Liao Xiao-Ping , Liu Ya-Hong , Zhang Gui-Hong , Zhou Xiao-Ming
Published: May 2019

Colorimetric gene detection based on gold nanoparticles (AuNPs) is an attractive detection format due to its simplicity. Here, we report a new design for a colorimetric gene-sensing platform based on the CRISPR/Cas system that has improved specificity, sensitivity, and universality. CRISPR/Cas12a and CRISPR/Cas13a have two distinct catalytic activities and are used for specific target gene recognition. Programmable recognition of DNA by Cas12a/crRNA and RNA by Cas13a/crRNA with a complementary sequence activates the nonspecific trans-ssDNA or -RNA cleavage, respectively, thus degrading the ssDNA or RNA linkers which are designed as a hybridization template for the AuNP-DNA probe pair. Target-induced trans -ssDNA or RNA cleavage leads to a distance-dependent color change for the AuNP-DNA probe pair. In this platform, naked eye detection of transgenic rice, African swine fever virus (ASFV), and a miRNA can be completed within 1 hour. Our colorimetric gene-sensing method shows superior characteristics, such as probe universality, isothermal reaction conditions, on-site detection capability, and sensitivity that is comparable to that of the fluorescent detection; thus, this method represents a robust next generation gene detection platform.
Influence of nanopillar arrays on fibroblast motility, adhesion and migration mechanisms
Authors: Beckwith Kai S. , Ullmann Sindre , Vinje Jakob , Sikorski Pawel
Published: May 2019

Surfaces decorated with high aspect ratio nanostructures are a promising tool to study cellular processes and design novel devices to control cellular behaviour, perform intracellular sensing or deliver effector molecules to cells in culture. However, little is known about the dynamics of cellular phenomenon such as adhesion, spreading and migration on such surfaces. In particular, how these are influenced by the surface properties. In this work, we investigate fibroblast behaviour on regular arrays of 1 micrometer high, polymer nanopillars with varying pillar to pillar distance (array pitch). NIH-3T3 fibroblasts spread on all arrays, and on contact with the substrate engulf nanopillars independently of the array pitch. As the cells start to spread, different behaviour is observed. On dense arrays which have the pitch equal or below 1 micrometer, cells are suspended on top of the nanopillars, making only sporadic contact with the glass support. Cells stay attached to the glass support and fully engulf nanopillars during spreading and migration on the sparse arrays which are characterized by a pitch of 2 micrometers and above. These alternate states have a profound effect on cell migration rates, which are strongly reduced on nanopillar sparse arrays. Dynamic actin puncta colocalize with nanopillars during cell spreading and migration. Strong membrane association with engulfed nanopillars might explain the reduced migration rates on sparse arrays. This work reveals several interesting phenomenon of dynamical cell behaviour on nanopillar arrays, and provides important perspectives on design and applications of high aspect ratio nanostructures.
Transcriptomic evidence that von Economo neurons are regionally specialized extratelencephalic-projecting excitatory neurons
Authors: Hodge Rebecca D , Miller Jeremy A , Novotny Mark , Kalmbach Brian E , Ting Jonathan T , Bakken Trygve E , Aevermann Brian D , Barkan Eliza R , Berkowitz-Cerasano Madeline L , Cobbs Charles , Diez-Fuertes Francisco , Ding Song-Lin , McCorrison Jamison , Schork Nicholas J , Shehata Soraya I , Smith Kimberly A , Sunkin Susan M , Tran Danny N , Venepally Pratap , Yanny Anna Marie , Steemers Frank J , Phillips John W , Bernard Amy , Koch Christof , Lasken Roger S , Scheuermann Richard H , Lein Ed S
Published: May 2019

von Economo neurons (VENs) are bipolar, spindle-shaped neurons restricted to layer 5 of human frontoinsula and anterior cingulate cortex that appear to be selectively vulnerable to neuropsychiatric and neurodegenerative diseases, although little is known about other VEN cellular phenotypes. Single nucleus RNA-sequencing of frontoinsula layer 5 identified a transcriptomically-defined cell cluster that contained VENs, but also fork cells and a subset of pyramidal neurons. Cross-species alignment of this cell cluster with a well-annotated mouse classification shows strong homology to extratelencephalic (ET) excitatory neurons that project to subcerebral targets. This cluster also shows strong homology to a putative ET cluster in human temporal cortex, but with a strikingly specific regional signature. Together these results predict VENs are a regionally distinctive type of ET neuron, and we additionally describe the first patch clamp recordings of VENs from neurosurgically-resected tissue that show distinctive intrinsic membrane properties relative to neighboring pyramidal neurons.