bluuebunny/crossref_metadata_2025 huggingface dataset:
Dissection of Incomplete Fissure Using Electrocautery Is a Safe and Acceptable Method for Thoracoscopic Right Upper Lobectomy
Authors: Xu Hao , Zhang Linyou
Published: May 2018

Objective The incidence of prolonged air leak may be highest after right upper lobectomy due to incomplete minor fissure. The objective of this study was to compare the efficacy of direct electrocautery division and suture with that of a fissureless technique during thoracoscopic right upper lobectomy with incomplete fissure.

Methods One hundred and two patients underwent right upper lobectomy between January 2016 and December 2016. Of these, 60 patients underwent a right upper lobectomy conducted using the fissureless technique (group A), and 42 consecutive patients underwent a right upper lobectomy via electrocautery division of the fissure and suture (group B). The preoperative, operative, and postoperative parameters were compared between the two groups.

Results The electrocautery and suture group had a higher incidence of prolonged air leak (> 5 days) (30% [12/40] vs 11% [7/62], p = 0.00), a higher incidence of air leakage (20 [32%] vs 38 [95%], p = 0.00), a longer air leak duration (days) (4.93 ± 0.86 vs 3.00 ± 1.60 days, p = 0.00), a longer duration of chest tube (mean 5.30 ± 1.20 vs 3.13 ± 1.88 days, p = 0.00), and a lower hospitalization cost (6463.28 ± 958.30 vs 7459.07 ± 1185.00 €, p = 0.00) than did the fissureless technique group. No differences were observed with respect to patient characteristics, operative characteristics, perioperative mortality, or duration of hospital stay after surgery.

Conclusions The number of patients with prolonged air leak was higher in the electrocautery group. However, electrocautery does not prolong overall length of stay and decreases hospitalization costs. Dissection of incomplete fissure using electrocautery is a safe and acceptable method for thoracoscopic right upper lobectomy.
An extended transfer operator approach to identify separatrices in open flows
Authors: Lünsmann Benedict , Kantz Holger
Published: May 2018

Vortices of coherent fluid volume are considered to have a substantial impact on transport processes in turbulent media. Yet, due to their Lagrangian nature, detecting these structures is highly nontrivial. In this respect, transfer operator approaches have been proven to provide useful tools: Approximating a possibly time-dependent flow as a discrete Markov process in space and time, information about coherent structures is contained in the operator's eigenvectors, which is usually extracted by employing clustering methods. Here, we propose an extended approach that couples surrounding filaments using “mixing boundary conditions” and focuses on the separation of the inner coherent set and embedding outer flow. The approach refrains from using unsupervised machine learning techniques such as clustering and uses physical arguments by maximizing a coherence ratio instead. We show that this technique improves the reconstruction of separatrices in stationary open flows and succeeds in finding almost-invariant sets in periodically perturbed flows.
Electric force on plasma ions and the momentum of the ion-neutrals flow
Authors: Makrinich G. , Fruchtman A. , Zoler D. , Boxman R. L.
Published: May 2018

The electric force on ions in plasma and the momentum flux carried by the mixed ion-neutral flow were measured and found to be equal. The experiment was performed in a direct-current gas discharge of cylindrical geometry with applied radial electric field and axial magnetic field. The unmagnetized plasma ions, neutralized by magnetized electrons, were accelerated radially outward transferring part of the gained momentum to neutrals. Measurements were taken for various argon gas flow rates between 13 and 100 Standard Cubic Centimeter per Minute, for a discharge current of 1.9 A and a magnetic field intensity of 136 G. The plasma density, electron temperature, and plasma potential were measured at various locations along the flow. These measurements were used to determine the local electric force on the ions. The total electric force on the plasma ions was then determined by integrating radially the local electric force. In parallel, the momentum flux of the mixed ion-neutral flow was determined by measuring the force exerted by the flow on a balance force meter (BFM). The maximal plasma density was between 6 × 1010 cm−3 and 5 × 1011 cm−3, the maximal electron temperature was between 8 eV and 25 eV, and the deduced maximal electric field was between 2200 V/m and 5800 V/m. The force exerted by the mixed ion-neutral flow on the BFM agreed with the total electric force on the plasma ions. This agreement showed that it is the electric force on the plasma ions that is the source of the momentum acquired by the mixed ion-neutral flow.
An instrument for in situ time-resolved X-ray imaging and diffraction of laser powder bed fusion additive manufacturing processes
Authors: Calta Nicholas P. , Wang Jenny , Kiss Andrew M. , Martin Aiden A. , Depond Philip J. , Guss Gabriel M. , Thampy Vivek , Fong Anthony Y. , Weker Johanna Nelson , Stone Kevin H. , Tassone Christopher J. , Kramer Matthew J. , Toney Michael F. , Van Buuren Anthony , Matthews Manyalibo J.
Published: May 2018

In situ X-ray-based measurements of the laser powder bed fusion (LPBF) additive manufacturing process produce unique data for model validation and improved process understanding. Synchrotron X-ray imaging and diffraction provide high resolution, bulk sensitive information with sufficient sampling rates to probe melt pool dynamics as well as phase and microstructure evolution. Here, we describe a laboratory-scale LPBF test bed designed to accommodate diffraction and imaging experiments at a synchrotron X-ray source during LPBF operation. We also present experimental results using Ti-6Al-4V, a widely used aerospace alloy, as a model system. Both imaging and diffraction experiments were carried out at the Stanford Synchrotron Radiation Lightsource. Melt pool dynamics were imaged at frame rates up to 4 kHz with a ∼1.1 μm effective pixel size and revealed the formation of keyhole pores along the melt track due to vapor recoil forces. Diffraction experiments at sampling rates of 1 kHz captured phase evolution and lattice contraction during the rapid cooling present in LPBF within a ∼50 × 100 μm area. We also discuss the utility of these measurements for model validation and process improvement.
On the radiated EMI current extraction of dc transmission line based on corona current statistical measurements
Authors: Yi Yong , Chen Zhengying , Wang Liming
Published: May 2018

Corona-originated discharge of DC transmission lines is the main reason for the radiated electromagnetic interference (EMI) field in the vicinity of transmission lines. A joint time-frequency analysis technique was proposed to extract the radiated EMI current (excitation current) of DC corona based on corona current statistical measurements. A reduced-scale experimental platform was setup to measure the statistical distributions of current waveform parameters of aluminum conductor steel reinforced. Based on the measured results, the peak value, root-mean-square value and average value with 9 kHz and 200 Hz band-with of 0.5 MHz radiated EMI current were calculated by the technique proposed and validated with conventional excitation function method. Radio interference (RI) was calculated based on the radiated EMI current and a wire-to-plate platform was built for the validity of the RI computation results. The reason for the certain deviation between the computations and measurements was detailed analyzed.
Measuring noise in microwave metamaterials
Authors: Wiltshire M. C. K. , Syms R. R. A.
Published: May 2018

Electromagnetic metamaterials are artificially constructed media composed of arrays of electrical circuits that can exhibit electric and magnetic characteristics unlike those of any conventional materials. However, the materials are lossy and hence noisy, so that the signal-to-noise ratio in practical situations is greatly reduced. In particular, operating in the double negative region, where both the permittivity and the permeability are negative so that the refractive index is real but negative, incurs significant loss and noise penalties. In this work, we report noise measurements on a double negative metamaterial at microwave frequencies and compare them with the results of a simple model based on a transmission line loaded with lossy elements that mimic the split ring resonators and fine wires of the metamaterial. A noise source is associated with the resistive part of each element, and these are added incoherently to predict the total noise spectrum of the metamaterial. The theoretical results are in good agreement with the measurements. In particular, we find that the measured noise spectrum has contributions from both electric and magnetic noise, but is dominated by the magnetic noise. This limits possible applications, even with optimised materials, to functions that cannot be realised by conventional means.
Influence of quantizing magnetic field and Rashba effect on indium arsenide metal-oxide-semiconductor structure accumulation capacitance
Authors: Kovchavtsev A. P. , Aksenov M. S. , Tsarenko A. V. , Nastovjak A. E. , Pogosov A. G. , Pokhabov D. A. , Tereshchenko O. E. , Valisheva N. A.
Published: May 2018

The accumulation capacitance oscillations behavior in the n-InAs metal-oxide-semiconductor structures with different densities of the built-in charge (Dbc) and the interface traps (Dit) at temperature 4.2 K in the magnetic field (B) 2–10 T, directed perpendicular to the semiconductor-dielectric interface, is studied. A decrease in the oscillation frequency and an increase in the capacitance oscillation amplitude are observed with the increase in B. At the same time, for a certain surface accumulation band bending, the influence of the Rashba effect, which is expressed in the oscillations decay and breakdown, is traced. The experimental capacitance-voltage curves are in a good agreement with the numeric simulation results of the self-consistent solution of Schrödinger and Poisson equations in the magnetic field, taking into account the quantization, nonparabolicity of dispersion law, and Fermi-Dirac electron statistics, with the allowance for the Rashba effect. The Landau quantum level broadening in a two-dimensional electron gas (Lorentzian-shaped density of states), due to the electron scattering mechanism, linearly depends on the magnetic field. The correlation between the interface electronic properties and the characteristic scattering times was established.
Rate equation analysis and non-Hermiticity in coupled semiconductor laser arrays
Authors: Gao Zihe , Johnson Matthew T. , Choquette Kent D.
Published: May 2018

Optically coupled semiconductor laser arrays are described by coupled rate equations. The coupled mode equations and carrier densities are included in the analysis, which inherently incorporate the carrier-induced nonlinearities including gain saturation and amplitude-phase coupling. We solve the steady-state coupled rate equations and consider the cavity frequency detuning and the individual laser pump rates as the experimentally controlled variables. We show that the carrier-induced nonlinearities play a critical role in the mode control, and we identify gain contrast induced by cavity frequency detuning as a unique mechanism for mode control. Photon-mediated energy transfer between cavities is also discussed. Parity-time symmetry and exceptional points in this system are studied. Unbroken parity-time symmetry can be achieved by judiciously combining cavity detuning and unequal pump rates, while broken symmetry lies on the boundary of the optical locking region. Exceptional points are identified at the intersection between broken symmetry and unbroken parity-time symmetry.
Reflected wave manipulation by inhomogeneous impedance via varying-depth acoustic liners
Authors: Guo Jingwen , Zhang Xin , Fang Yi , Fattah Ryu
Published: May 2018

Acoustic liners, consisting of a perforated panel affixed to a honeycomb core with a rigid back plate, are widely used for noise attenuation purpose. In this study, by exploiting inhomogeneous impedance properties, we report an experimental and numerical study on a liner-type acoustic metasurface, which possesses the functionality of both reflected wave manipulation and sound energy attenuation simultaneously. To realize the inhomogeneous acoustic impedance, an acoustic metasurface constructed by varying-depth acoustic liners is designed and fabricated. The reflected sound pressure fields induced by the metasurface are obtained in both experiments and simulations. A complete characterization of this metasurface is performed, including the effects of depth gradient, incident angle, and incident frequency. Anomalous reflection, apparent negative reflection, and conversion from an incident wave to a surface wave with strong energy dissipation are achieved by the structure. Moreover, our proposed structure can overcome the single frequency performance limitation that exists in conventional metasurfaces and performs well in a broadband frequency range. The proposed acoustic metasurface offers flexibility in controlling the direction of sound wave propagation with energy dissipation property and holds promise for various applications of noise reduction.
Plasmon modes in monolayer and double-layer black phosphorus under applied uniaxial strain
Authors: Saberi-Pouya S. , Vazifehshenas T. , Saleh M. , Farmanbar M. , Salavati-fard T.
Published: May 2018

We study the effects of an applied in-plane uniaxial strain on the plasmon dispersions of monolayer, bilayer, and double-layer black phosphorus structures in the long-wavelength limit within the linear elasticity theory. In the low-energy limit, these effects can be modeled through the change in the curvature of the anisotropic energy band along the armchair and zigzag directions. We derive analytical relations of the plasmon modes under uniaxial strain and show that the direction of the applied strain is important. Moreover, we observe that along the armchair direction, the changes of the plasmon dispersion with strain are different and larger than those along the zigzag direction. Using the analytical relations of two-layer phosphorene systems, we found that the strain-dependent orientation factor of layers could be considered as a means to control the variations of the plasmon energy. Furthermore, our study shows that the plasmonic collective modes are more affected when the strain is applied equally to the layers compared to the case in which the strain is applied asymmetrically to the layers. We also calculate the effect of strain on the drag resistivity in a double-layer black phosphorus structure and obtain that the changes in the plasmonic excitations, due to an applied strain, are mainly responsible for the predicted results. This study can be readily extended to other anisotropic two-dimensional materials.
Note: A 3D-printed alkali metal dispenser
Authors: Norrgard E. B. , Barker D. S. , Fedchak J. A. , Klimov N. , Scherschligt J. , Eckel S.
Published: May 2018

We demonstrate and characterize a source of Li atoms made from direct metal laser sintered titanium. The source’s outgassing rate is measured to be 5(2) × 10−7 Pa L s−1 at a temperature T = 330 °C, which optimizes the number of atoms loaded into a magneto-optical trap. The source loads ≈107 7Li atoms in the trap in ≈1 s. The loaded source weighs 700 mg and is suitable for a number of deployable sensors based on cold atoms.
Photoelectrochemical response of GaN, InGaN, and GaNP nanowire ensembles
Authors: Philipps Jan M. , Hölzel Sara , Hille Pascal , Schörmann Jörg , Chatterjee Sangam , Buyanova Irina A. , Eickhoff Martin , Hofmann Detlev M.
Published: May 2018

The photoelectrochemical responses of GaN, GaNP, and InGaN nanowire ensembles are investigated by the electrical bias dependent photoluminescence, photocurrent, and spin trapping experiments. The results are explained in the frame of the surface band bending model. The model is sufficient for InGaN nanowires, but for GaN nanowires the electrochemical etching processes in the anodic regime have to be considered additionally. These processes lead to oxygen rich surface (GaxOy) conditions as evident from energy dispersive X-ray fluorescence. For the GaNP nanowires, a bias dependence of the carrier transfer to the electrolyte is not reflected in the photoluminescence response, which is tentatively ascribed to a different origin of radiative recombination in this material as compared to (In)GaN. The corresponding consequences for the applications of the materials for water splitting or pH-sensing will be discussed.
Lateral hydrogen microsensors prepared on-chip by local oxidation of platinum-decorated titanium films
Authors: Herbertz S. , Welk D. , Heinzel T.
Published: May 2018

Titanium microstripes on silicon dioxide substrates are oxidized locally by applying voltages on-chip to lateral electrodes under ambient conditions. This technique enables profound modifications of the electronic circuit. As an example, we transform Ti films decorated by a sub-monolayer of platinum into hydrogen gas microsensors in an otherwise completed device by a silicon-MOS compatible process.
Out-of-plane electron transport in finite layer MoS2
Authors: Holzapfel R. , Weber J. , Lukashev P. V. , Stollenwerk A. J.
Published: May 2018

Ballistic electron emission microscopy (BEEM) has been used to study the processes affecting electron transport along the [0001] direction of finite layer MoS2 flakes deposited onto the surface of Au/Si(001) Schottky diodes. Prominent features present in the differential spectra from the MoS2 flakes are consistent with the density of states of finite layer MoS2 calculated using density functional theory. The ability to observe the electronic structure of the MoS2 appears to be due to the relatively smooth density of states of Si in this energy range and a substantial amount of elastic or quasi-elastic scattering along the MoS2/Au/Si(001) path. Demonstration of these measurements using BEEM suggests that this technique could potentially be used to study electron transport through van der Waals heterostructures, with applications in a number of electronic devices.
Communication: Glass transition and melting lines of an ionic liquid
Authors: Lima Thamires A. , Faria Luiz F. O. , Paschoal Vitor H. , Ribeiro Mauro C. C.
Published: May 2018

The phase diagram of the ionic liquid 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesufonyl)imide, [Pyrr1,4][NTf2], was explored by synchroton X-ray diffraction and Raman scattering measurements as a function of temperature and pressure. Glass transition Tg(p) and melting Tm(p) temperatures were obtained from atmospheric pressure up to ca. 2.0 GPa. We found that both the Tg(p) and Tm(p) curves follow essentially the same pressure dependence. The similarity of pressure coefficients, dTg/dp ≈ dTm/dp, is explained within the non-equilibrium thermodynamics approach for the glass transition by assuming that one of the Ehrenfest equations is appropriated for Tg(p), whereas Tm(p) follows the Clausius-Clapeyron equation valid for the first-order transitions. The results highlight that ionic liquids are excellent model systems to address fundamental questions related to the glass transition.
Pronounced photogating effect in atomically thin WSe2 with a self-limiting surface oxide layer
Authors: Yamamoto Mahito , Ueno Keiji , Tsukagoshi Kazuhito
Published: May 2018

The photogating effect is a photocurrent generation mechanism that leads to marked responsivity in two-dimensional (2D) semiconductor-based devices. A key step to promote the photogating effect in a 2D semiconductor is to integrate it with a high density of charge traps. Here, we show that self-limiting surface oxides on atomically thin WSe2 can serve as effective electron traps to facilitate p-type photogating. By examining the gate-bias-induced threshold voltage shift of a p-type transistor based on single-layer WSe2 with surface oxide, the electron trap density and the trap rate of the oxide are determined to be >1012 cm−2 and >1010 cm−2 s−1, respectively. White-light illumination on an oxide-covered 4-layer WSe2 transistor leads to the generation of photocurrent, the magnitude of which increases with the hole mobility. During illumination, the photocurrent evolves on a timescale of seconds, and a portion of the current persists even after illumination. These observations indicate that the photogenerated electrons are trapped deeply in the surface oxide and effectively gate the underlying WSe2. Owing to the pronounced photogating effect, the responsivity of the oxide-covered WSe2 transistor is observed to exceed 3000 A/W at an incident optical power of 1.1 nW, suggesting the effectiveness of surface oxidation in facilitating the photogating effect in 2D semiconductors.
Neuroscientists network to study the whole brain
Authors: Feder Toni
Published: May 2018

The team effort is inspired by large physics collaborations.
Synthesizing molecular fishing nets
Authors: Servalli Marco , Öttinger Hans Christian , Schlüter A. Dieter
Published: May 2018

The power of organic chemistry is opening new possibilities for building customized two-dimensional materials.
How can sedentarised pastoralists be more technically efficient? A case from eastern Inner Mongolia
Authors: Tan Shuhao , Li Tingyu , Liu Bo , Huntsinger Lynn
Published: May 2018

Technical efficiency (TE) means the effectiveness of production outputs attained for a given level of production inputs. This study examines pastoralist TE and its determinants for 416 pastoralist households from two leagues (prefectures) in eastern Inner Mongolia, a typical rangeland area in China. A one-step stochastic frontier method is applied to analyse data about household livestock production in 2011 to assess opportunities for increasing income and reducing poverty through increased TE. The main results show that pastoralists, in general, did not perform well with currently available technology, with the average TE score just 0.50 out of 1.0. Only about one-fifth (20.2%) of respondents had TE scores >0.7, and the same proportion had a TE score <0.3. More than one-quarter had TE scores in the range 0.3–0.5, and slightly more than one-third had TE scores in the range 0.5–0.7. About 83% of the variation in pastoralist livestock production is explained by the loss of TE. The age of the head of household, available pasture, investment in covered pens and participation in the rangeland rental market were found to influence TE. Encouraging younger pastoralists to enter pastoralism, and enlarging available grazing land through the rangeland rental market or cooperative rangeland use would likely enhance pastoralist performance; promoting investment in covered-pen construction could also improve productivity and alleviate a rangeland degradation cycle, which is pervasive in the study area.
Cell-free formation and interactome analysis of caveolae
Authors: Jung WooRam , Sierecki Emma , Bastiani Michele , O’Carroll Ailis , Alexandrov Kirill , Rae James , Johnston Wayne , Hunter Dominic J.B. , Ferguson Charles , Gambin Yann , Ariotti Nicholas , Parton Robert G.
Published: May 2018

Caveolae have been linked to the regulation of signaling pathways in eukaryotic cells through direct interactions with caveolins. Here, we describe a cell-free system based on Leishmania tarentolae (Lt) extracts for the biogenesis of caveolae and show its use for single-molecule interaction studies. Insertion of expressed caveolin-1 (CAV1) into Lt membranes was analogous to that of caveolin in native membranes. Electron tomography showed that caveolins generate domains of precise size and curvature. Cell-free caveolae were used in quantitative assays to test the interaction of membrane-inserted caveolin with signaling proteins and to determine the stoichiometry of interactions. Binding of membrane-inserted CAV1 to several proposed binding partners, including endothelial nitric-oxide synthase, was negligible, but a small number of proteins, including TRAF2, interacted with CAV1 in a phosphorylation-(CAV1Y14)–stimulated manner. In cells subjected to oxidative stress, phosphorylated CAV1 recruited TRAF2 to the early endosome forming a novel signaling platform. These findings lead to a novel model for cellular stress signaling by CAV1.
Synthesis of Eugenol–Lauryl Methacrylate Copolymers via Cationic Polymerization
Authors: Fajrin A , Marliana SD , Handayani D S
Published: May 2018

Eugenol is one of the most abundant natural resources in Indonesia. The recently bio-based polymer resin is created based on eugenol because eugenol is functionalized with the polymerizable group. In order to improve the functional properties of eugenol, in this research Eugenol–Lauryl Methacrylate copolymers (co-poly(Eg-LMA)) were synthesized by cationic polymerization using H2SO4 as an initiator under the nitrogen atmosphere. Structure identification of the copolymer showed the absorption of the vinyl group from the monomers disappear at the analysis through FTIR at the wave number 1637-1639 and 985-995 cm-1 and also 1H-NMR on the chemical shift 5,97 and 5,08 ppm. The resulting copolymers obtained brown powder in 32.03 % yieldsand melting point at 96 – 97 °C. Solubility test of the co-poly(Eg-LMA) showed that the polymer couldnot soluble in water but soluble in chloroform, diethyl ether, and benzene. Average molecular weight of co-poly(Eg-LMA) Led Ostwald viscometry was obtained 42020 with the degree of polymerization by 200.
The Long‐Term Effects of Meat Recalls on Futures Markets
Authors: Houser Matthew , Dorfman Jeffrey H , Rejesus Roderick M
Published: May 2018

Over the past twenty years, there has been an increasing trend in the number of food safety events. Despite increased safety control standards, foodborne disease outbreaks continue to impact the food supply. A common source of foodborne illness and fatal infection is beef, with potential causes being E. coli 0157: H7, Listeria Monocytogenes, and Salmonella. Certain companies have even been bankrupted, unable to overcome the social costs and economic losses associated with recalls. We look beyond the impact on processors to see the amount of impact transmitted through price channels to cattle farmers. We examine beef recalls over a twenty‐year period through an accumulated two‐year index to see if there is a prolonged effect of recalls on current weekly cattle prices. We find that food safety events act together, adversely impacting prices and decreasing farm‐level revenue. The finding that economic harm to the beef industry from food safety events lingers for at least two years suggests that the industry should do more to reduce food safety incidents.
Greenhouse Gas Emissions, Land Use, and Food Supply under the Paris Climate Agreement—Policy Choice in Norway
Authors: Blandford David , Gaasland Ivar , Vårdal Erling
Published: May 2018

We study the potential for reducing agricultural greenhouse gas (GHG) emissions without sacrificing food security in Norway. We show that it is possible to achieve a 40% reduction in direct agricultural emissions without compromising domestic food supply in terms of calories and protein. Combined GHG and food supply targets can be met using substantially less land and agricultural support. Dietary changes involve a 30% reduction in meat consumption and a 10% to 20% reduction in the consumption of dairy products, counterbalanced by increased consumption of vegetable products. Although the numerical results are specific to Norway, they are relevant for other rich countries. A consistent pattern in these countries is that ruminant animals impose a heavy toll in terms of both GHG emissions and land use relative to their contribution to food energy production.
Cluster-Randomized Test-Negative Design Trials: A Novel and Efficient Method to Assess the Efficacy of Community-Level Dengue Interventions
Authors: Anders Katherine L , Cutcher Zoe , Kleinschmidt Immo , Donnelly Christl A , Ferguson Neil M , Indriani Citra , Ryan Peter A , O’Neill Scott L , Jewell Nicholas P , Simmons Cameron P
Published: May 2018

Cluster-randomized controlled trials are the gold standard for assessing efficacy of community-level interventions, such as vector-control strategies against dengue. We describe a novel cluster-randomized trial methodology with a test-negative design (CR-TND), which offers advantages over traditional approaches. This method uses outcome-based sampling of patients presenting with a syndrome consistent with the disease of interest, who are subsequently classified as test-positive cases or test-negative controls on the basis of diagnostic testing. We used simulations of a cluster trial to demonstrate validity of efficacy estimates under the test-negative approach. We demonstrated that, provided study arms are balanced for both test-negative and test-positive illness at baseline and that other test-negative design assumptions are met, the efficacy estimates closely match true efficacy. Analytical considerations for an odds ratio–based effect estimate arising from clustered data and potential approaches to analysis are also discussed briefly. We concluded that application of the test-negative design to certain cluster-randomized trials could increase their efficiency and ease of implementation.
Relationship of the oxidative damage biomarker 8-epi-prostaglandin F2α to risk of lung cancer development in the Shanghai Cohort Study
Authors: Yuan Jian-Min , Carmella Steven G , Wang Renwei , Tan Yu-Ting , Adams-Haduch Jennifer , Gao Yu-Tang , Hecht Stephen S
Published: May 2018

It has been hypothesized that the pathogenesis of lung cancer induced by cigarette smoking involves oxidative damage by free radicals. Epidemiological data on biomarkers of oxidative damage and risk of lung cancer development are sparse. A nested case–control study of 610 lung cancer cases and 610 matched controls was conducted within a prospective cohort of 18 244 Chinese men in Shanghai, China. The concentrations of 8-epi-prostaglandin F2α (8-epiPGF2α), a biomarker of oxidative stress, were determined in baseline urine samples using a validated mass-spectrometry assay. Current smokers had significantly higher level of 8-epiPGF2α than former smokers or never smokers (P < 0.001). 8-epiPGF2α levels were significantly higher in lung cancer cases than their smoking-matched controls in former and current smokers, but not different in never smokers (P for interaction = 0.019). The relative risks of developing lung cancer for former and current smokers in the highest relative to the lowest quartile of 8-epiPGF2α were 5.25 (Ptrend = 0.035) and 1.99 (Ptrend =0.007), respectively. The effect of 8-epiPGF2α and biomarkers of cigarette smoke exposure on lung cancer risk was additive; the relative risk was 5.33 (95% confidence interval = 2.65–7.51) for current smokers with the highest thirds of 8-epiPGF2α and total cotinine compared with their lowest thirds. Smokers with a heightened state of oxidative stress in response to the insults of cigarette smoking may be more susceptible to smoking-induced lung carcinogenesis.
Determinants of incentive preferences for health behavior change in Japan
Authors: Takada Toshihiko , Fukuma Shingo , Yamamoto Yosuke , Shimizu Sayaka , Nihata Kakuya , Miyashita Jun , Azuma Teruhisa , Hayashi Michio , Fukuhara Shunichi
Published: May 2018

Interest in the use of incentives to promote health behavior change has been growing worldwide. However, to develop an effective incentive program, accurate information regarding individual preferences is essential. Therefore, the aim of this study was to clarify determinants of incentive preferences for health behavior change. A self-completed questionnaire survey regarding incentives for health behavior change was conducted in a Japanese village in 2015. The outcome measures were individual preferences for features of incentives, including item, frequency, type and value. The types of incentives were defined as follows: assured-type (given for participation); effort-type (given if participants make some kind of effort); and outcome-type (given if participants make achievements decided a priori). The associations with respondents’ sex, age, presence of lifestyle-related disease and stage in the transtheoretical model of health behavior change were investigated using multivariate analysis. A total of 1469 residents responded to the survey. Significant associations with preference for different incentive features were found as follows: for monetary items, female and elderly; for high frequency, female and maintenance stage; for effort-type, male, action stage and contemplation stage; and for outcome-type, maintenance stage and action stage. Our results appeared to identify determinants of incentive preferences for health behavior change. These findings are expected to promote the development of an incentive program more in tune with individual preferences.
The Homology Class of a Poisson Transversal
Authors: Frejlich Pedro , Mărcuț Ioan
Published: May 2018

This note is devoted to the study of the homology class of a compact Poisson transversal in a Poisson manifold. For specific classes of Poisson structures, such as unimodular Poisson structures and Poisson manifolds with closed leaves, we prove that all their compact Poisson transversals represent nontrivial homology classes, generalizing the symplectic case. We discuss several examples in which this property does not hold, as well as a weaker version of this property, which holds for log-symplectic structures. Finally, we extend our results to Dirac geometry.
General Variational Formulas for Abelian Differentials
Authors: Hu Xuntao , Norton Chaya
Published: May 2018

We use the jump problem technique developed in a recent paper [9] to compute the variational formula of any stable differential and its periods to arbitrary precision in plumbing coordinates. In particular, we give the explicit variational formula for the degeneration of the period matrix, easily reproving the results of Yamada [21] for nodal curves with one node and extending them to an arbitrary stable curve. Concrete examples are included. We also apply the same technique to give an alternative proof of the sufficiency part of the theorem in [1] on the closures of strata of differentials with prescribed multiplicities of zeroes and poles.
Radiological Management of Angiographically Negative, Spontaneous Intracranial Subarachnoid Hemorrhage: A Multicenter Study of Utilization and Diagnostic Yield
Authors: Sadigh Gelareh , Menon Ranjith K , Bhojak Maneesh , Aladi Abather , Mossa-Basha Mahmud , Wu Lei , Lehman Vance T , Brinjikji Waleed , Dehkharghani Seena , Derakhshani Ahrya , Mossa-Basha Feras , Allen Jason W
Published: May 2018

BACKGROUND

The optimal diagnostic evaluation for patients with angiographically negative subarachnoid hemorrhage (AN-SAH) remains controversial.

OBJECTIVE

To assess the utilization rate and diagnostic yield of imaging tests routinely obtained in identifying a structural cause for AN-SAH.

METHODS

In this retrospective multicenter study, consecutive adult patients admitted with nontraumatic, AN-SAH between 01/2010 and 12/2015 were included. Patients with intraparenchymal, subdural, or epidural hematomas in addition to SAH were excluded. Outcomes studied included utilization rate, diagnostic yield, and median time from admission for the following imaging tests: initial computed tomography angiography (CTA) and digital subtraction angiography (DSA), brain and cervical spine magnetic resonance imaging (MRI), and any repeat DSA or CTA performed either during initial admission or at long-term follow-up.

RESULTS

A total of 752 patients were included (mean age, 53 yr; 54% male). Initial CTA and DSA were performed in 89% and 100% of patients, respectively. Brain MRI was performed in 75% of patients and was positive in 0.7% of cases. Cervical spine MRI was performed in 61% of patients and was positive in 0.2% of cases. Repeat, same-admission follow-up DSA and CTA were performed in 48% and 51% of patients and were positive in 3.3% and 1% of cases, respectively. Delayed follow-up DSA and CTA after discharge were performed in 26% and 7% of patients and were positive in 2% and 3.7% of cases, respectively, all with negative prior imaging studies.

CONCLUSION

Cervical spine and brain MRI have extremely low diagnostic yield, both are commonly utilized in patients with AN-SAH; while repeat DSA and CTA are utilized less commonly and have slightly higher diagnostic yield.
Overcoming Challenges of Cranial Nerve Tractography: A Targeted Review
Authors: Jacquesson Timothée , Frindel Carole , Kocevar Gabriel , Berhouma Moncef , Jouanneau Emmanuel , Attyé Arnaud , Cotton Francois
Published: May 2018

BACKGROUND

Diffusion imaging tractography caught the attention of the scientific community by describing the white matter architecture in vivo and noninvasively, but its application to small structures such as cranial nerves remains difficult. The few attempts to track cranial nerves presented highly variable acquisition and tracking settings.

OBJECTIVE

To conduct and present a targeted review collecting all technical details and pointing out challenges and solutions in cranial nerve tractography.

METHODS

A “targeted” review of the scientific literature was carried out using the MEDLINE database. We selected studies that reported how to perform the tractography of cranial nerves, and extracted the following: clinical context; imaging acquisition settings; tractography parameters; regions of interest (ROIs) design; and filtering methods.

RESULTS

Twenty-one published articles were included. These studied the optic nerves in suprasellar tumors, the trigeminal nerve in neurovascular conflicts, the facial nerve position around vestibular schwannomas, or all cranial nerves. Over time, the number of MRI diffusion gradient directions increased from 6 to 101. Nine tracking software packages were used which offered various types of tridimensional display. Tracking parameters were disparately detailed except for fractional anisotropy, which ranged from 0.06 to 0.5, and curvature angle, which was set between 20° and 90°. ROI design has evolved towards a multi-ROI strategy. Furthermore, new algorithms are being developed to avoid spurious tracts and improve angular resolution.

CONCLUSION

This review highlights the variability in the settings used for cranial nerve tractography. It points out challenges that originate both from cranial nerve anatomy and the tractography technology, and allows a better understanding of cranial nerve tractography.
Systematic Review of Factors Influencing Smoking Following Release From Smoke-Free Prisons
Authors: Puljević Cheneal , Segan Catherine J
Published: May 2018

Introduction

Given the current proliferation of prison smoke-free policies internationally, and the multiple benefits of continued smoking abstinence for correctional populations, improved understanding of factors influencing postrelease smoking abstinence is required to inform support strategies aimed at individuals exiting smoke-free prisons.

Methods

We systematically searched health, social science, and criminal justice databases for studies relating to smoking behaviors among people released from smoke-free prisons. Studies were included if: they were published between January 1, 2000 and July 26, 2017; they were published in English; the population was people who were incarcerated or formerly incarcerated in prisons with total smoke-free policies; and the reported outcomes included measures of: (1) prerelease intention to smoke or remain abstinent from smoking following release, (2) smoking relapse or abstinence following release, or (3) quit attempts following postrelease smoking relapse. Both authors independently screened returned citations to assess eligibility and reviewed studies for methodological quality using the Effective Public Health Practice Project’s Quality Assessment Tool for Quantitative Studies.

Results

Fifteen of 121 publications were included. The evidence base in this area is small, almost exclusively US-based, and is mostly methodologically weak. Interventions delivered both pre and postrelease, that strengthen intention to quit, integrate with other substance-use treatment, and facilitate social support for quitting may help maintain postrelease smoking abstinence.

Conclusions

There is an urgent need for high-quality research to inform interventions to reduce high smoking relapse rates upon release from smoke-free prisons, to extend the multiple benefits of continued smoking abstinence into the community.

Implications

Interventions designed to help people remain abstinent from tobacco following release from smoke-free prisons are an important opportunity to improve the health, finances, and well-being of this vulnerable population.
Fortran interface layer of the framework for developing particle simulator FDPS
Authors: Namekata Daisuke , Iwasawa Masaki , Nitadori Keigo , Tanikawa Ataru , Muranushi Takayuki , Wang Long , Hosono Natsuki , Nomura Kentaro , Makino Junichiro
Published: May 2018

Numerical simulations based on particle methods have been widely used in various fields including astrophysics. To date, various versions of simulation software have been developed by individual researchers or research groups in each field, through a huge amount of time and effort, even though the numerical algorithms used are very similar. To improve the situation, we have developed a framework, called FDPS (Framework for Developing Particle Simulators), which enables researchers to develop massively parallel particle simulation codes for arbitrary particle methods easily. Until version 3.0, FDPS provided an API (application programming interface) for the C++ programming language only. This limitation comes from the fact that FDPS is developed using the template feature in C++, which is essential to support arbitrary data types of particle. However, there are many researchers who use Fortran to develop their codes. Thus, the previous versions of FDPS require such people to invest much time to learn C++. This is inefficient. To cope with this problem, we developed a Fortran interface layer in FDPS, which provides API for Fortran. In order to support arbitrary data types of particle in Fortran, we design the Fortran interface layer as follows. Based on a given derived data type in Fortran representing particle, a Python script provided by us automatically generates a library that manipulates the C++ core part of FDPS. This library is seen as a Fortran module providing an API of FDPS from the Fortran side and uses C programs internally to interoperate Fortran with C++. In this way, we have overcome several technical issues when emulating a ‘template’ in Fortran. Using the Fortran interface, users can develop all parts of their codes in Fortran. We show that the overhead of the Fortran interface part is sufficiently small and a code written in Fortran shows a performance practically identical to the one written in C++.
Association of e-cigarette use with oral health: a population-based cross-sectional questionnaire study
Authors: Huilgol Priyanka , Bhatt Surya P , Biligowda Niranjan , Wright Nicole C , Wells J Michael
Published: May 2018

Background

The impact of daily or intermittent electronic cigarette (e-cigarette) use on oral health is unknown.

Methods

We performed a cross-sectional analysis using the 2016 Behavioral Risk Factor Surveillance System data. Poor oral health was determined by the number of permanent teeth removed due to non-traumatic causes, and e-cigarette use determined by daily or intermittent use within 30 days prior to survey administration. We performed logistic regression analysis to test associations between e-cigarette use and oral health with adjustment for factors associated with poor oral health, survey clustering, strata and weight.

Results

We included survey responses from 456 343 adults. Over half of respondents (51.5%) reported having at least one permanent tooth removed because of tooth decay or gum disease in their lifetime. Daily e-cigarette use was reported by 4957 (1.1%) of respondents. In multivariable analysis, daily e-cigarette use, was independently associated with a 78% higher odds of poor oral health (adjusted OR = 1.78, 95% CI: 1.39–2.30; P < 0.001).

Conclusions

In a population-based health survey of US adults, self-reported health behavior and outcomes, daily use, but not intermittent use of e-cigarettes was independently associated with poor oral health. Care must be exercised in seeking ‘healthier’ cigarette alternatives.
Identification of Chemotaxis Compounds in Root Exudates and Their Sensing Chemoreceptors in Plant-Growth-Promoting Rhizobacteria Bacillus amyloliquefaciens SQR9
Authors: Feng Haichao , Zhang Nan , Du Wenbin , Zhang Huihui , Liu Yunpeng , Fu Ruixin , Shao Jiahui , Zhang Guishan , Shen Qirong , Zhang Ruifu
Published: May 2018

Chemotaxis-mediated response to root exudates, initiated by sensing-specific ligands through methyl-accepting chemotaxis proteins (MCP), is very important for root colonization and beneficial functions of plant-growth-promoting rhizobacteria (PGPR). Systematic identification of chemoattractants in complex root exudates and their sensing chemoreceptors in PGPR is helpful for enhancing their recruitment and colonization. In this study, 39 chemoattractants and 5 chemorepellents, including amino acids, organic acids, and sugars, were identified from 98 tested components of root exudates for the well-studied PGPR strain Bacillus amyloliquefaciens SQR9. Interestingly, mutant stain SQR9Δ8mcp, with all eight putative chemoreceptors completely deleted, lost the chemotactic responses to those 44 compounds. Gene complementation, chemotaxis assay, and isothermal titration calorimetry analysis revealed that McpA was mainly responsible for sensing organic acids and amino acids, while McpC was mostly for amino acids. These two chemoreceptors may play important roles in the rhizosphere chemotaxis of SQR9. In contrast, the B. amyloliquefaciens-unique chemoreceptor McpR was specifically responsible for arginine, and residues Tyr-78, Thr-131, and Asp-162 were critical for arginine binding. This study not only deepened our insights into PGPR–root interaction but also provided useful information to enhance the rhizosphere chemotaxis mobility and colonization of PGPR, which will promote their application in agricultural production.
A Simple Culture Method Inducing Sexual Reproduction by Fusarium graminearum, the Primary Causal Agent of Fusarium Head Blight
Authors: Lu Shunwen , Edwards Michael C.
Published: May 2018

Fusarium graminearum, the primary pathogen of Fusarium head blight (FHB), undergoes both asexual and sexual stages, and the ascospore is an important primary inoculum of FHB. Induction of the sexual stage under laboratory conditions is important for the study of FHB. Here we report a simple culture method that uses potato dextrose agar plates. This method works as well as the traditional procedure, which depends on carrot extracts and involves multiple steps in preparation.