bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Lateral Cyclic Loading on Drilled Shaft within an MSE Wall
Authors: Huang Jie , Rahman Saidur , Bin-Shafique Sazzad , Zheng Chao , Malla Sandeep
Published: April 2019

Drilled shafts are often subjected to various lateral loads due to earth pressure, wind loads and/or impact loads. Many studies have investigated the behavior of drilled shafts under lateral loads. However, there is limited study on the effect of cyclic loading on drilled shafts, which is of great importance during a hurricane strike. This paper encompasses a numerical study using three-dimensional (3D) finite difference software, FLAC3D, which investigated interaction between a drilled shaft and an MSE wall under cyclic loading event. The backfill material was simulated by a stress-dependent model, which can account for the hardening due to confining stresses. The interactions between dissimilar materials were represented by frictional interface at the contacts. The numerical simulation scrutinized the effects of soil friction angle and the loading cycles on the performance of the drilled shaft and MSE wall under both loading and unloading conditions. The result indicates that the cyclic loading leads to gradual accumulation of the displacement, which cannot be effectively considered in current design method.
Effect of Water and Emulsifier on the Mechanical Properties of Cement Asphalt Mortar
Authors: Ho Minh Le Tri , Park Dae-Wook , Seo Jung-Woo
Published: April 2019

The long-term operation of high-speed railway leads to remarkable issues in ballast mechanical degradation and track irregularity. Particularly, in mainline of rail structure, the required time for ballast layer maintenance is strictly short. To systematically cope with this problem, a comprehensive study was proposed to develop a new cement asphalt mortar (CAM) stabilized ballast method. This solution is expected to improve the ballast structural durability with fast application time. However, the engineer properties of CAM paste with different level of initial mixing water as well as the influencing mechanisms are not clearly understood. In this work, the effects of initial mixing water and emulsifier on the mechanical performance of CAM are mainly discussed. The characteristics of the mortar were determined by conducting the flowability test, mixing stability test, and unconfined compressive strength (UCS) test. The test results revealed that the initial mixing water plays an important role in both fresh and hardened stage of CAM, especially the demulsification process of asphalt emulsion. Meanwhile, the emulsifier imposed a critical effect on the strength development of CAM mixture.
Performance Characteristics of Asphalt Binders containing Sodium-Alginate Hollow Fibers and Recycled Materials
Authors: Aguirre Max A. , Hassan Marwa M. , Shirzad Sharareh , Mohammad Louay N. , Cooper Samuel B. , Negulescu Ioan I.
Published: April 2019

Self-healing products such as hollow-fibers filled with an asphalt rejuvenator present an emerging technology that would enhance an asphalt mixture’s resistance to cracking damage. The objective of this study was to evaluate the rejuvenating efficiency of sodium-alginate fibers containing a rejuvenator product using asphalt binder blends containing extracted binder from recycled materials. The effects of adding extracted binder from recycled materials and sodium-alginate fibers on asphalt binder blends were evaluated by conducting a series of chemical and binder tests. HP-GPC and FTIR test results showed that the addition of fibers in blends containing recycled materials resulted in an increase in the HMW/LMW ratios. Some of the added polymeric fibers are thought to have increased the HMW fraction, thus leading to increase in the HMW/LMW ratio. The increase of the HMW fraction suggests that some of the fibers, which are polymers, caused the increase in the HMW/LMW ratios. MSCR test results showed that a binder blend with extracted binder from recycled materials and sodium-alginate fibers would have less rutting susceptibility than a conventional virgin binder would.
Smart illuminative Charging (SiC) of Future Electric Vehicles Using Roadway Infrastructure
Authors: Fernandez Daniel , Sebastian Ann , Ahn Ethan , Reda Taha Mahmoud , Dessouky Samer , Ahmed Sara
Published: April 2019

Inspired by the fact that there is an immense amount of renewable energy sources available on the roadways such as mechanical pressure and frictional heat, this paper presents the development and implementation of an innovative charging technique for future electric vehicles (EVs) by fully utilizing the existing roadways and the state-of-the-art nanotechnology. The paper introduces a novel wireless charging system that uses LEDs powered by piezoelectric nanomaterials as the energy transmitter source and thin film solar panels placed at the bottom of the EVs as the receiver, which is then poised to deliver the harvested energy to the vehicle’s battery. The lab-scale prototype device was developed to testify the proposed mechanism of illuminative charging (i.e., “light” couples pavement and vehicle as a wireless energy transfer medium), and the synthesized large-area nanomaterial produced high output voltages of up to 52 mV upon mechanical pressure.
Multimediales E-Learning in der Chirurgie, 10 Jahre Erfahrung an der Universität Würzburg
Authors: Wierlemann Alexander , Seyfried Florian , Germer Christoph Thomas
Published: April 2019

Hintergrund Digitale Inhalte im Internet sind zu einer wichtigen Lernressource für Studierende geworden. E-Learning kann einen wichtigen Beitrag leisten bei der Unterstützung von Lernprozessen. Gleichzeitig können Lehrangebote im Internet eine größere Zielgruppe erreichen als klassische Lehrformate.

Methoden Als Ergänzung des Lehrangebots der chirurgischen Universitätsklinik Würzburg wurde eine frei zugängliche E-Learning-Plattform etabliert, die den gesamten Themenbereich der Allgemein- und Viszeralchirurgie abbildet und die Themen multimedial aufbereitet interaktiv präsentiert.

Ergebnisse Im Zeitraum von Februar 2010 bis April 2018 wurden auf den verschiedenen Seiten des E-Learnings kumulativ 1 444 806 Seitenaufrufe verzeichnet von insgesamt 350 212 Nutzern. 24,04% der Nutzer griffen mit mobilen Endgeräten oder Tablets auf die Seiten zu.

Schlussfolgerung Mithilfe frei verfügbarer Open-Source-Software ist es möglich, ein modernes E-Learning-Angebot zu realisieren. Der Verzicht auf proprietäre Standards, die Berücksichtigung der Plattformunabhängigkeit sowie der Verzicht auf jegliche Zugangsbeschränkung helfen, die Reichweite des Angebots weit über die eigene Fakultät hinaus zu erhöhen. Bei zukünftigen Weiterentwicklungen wird die stärkere Personalisierung des Angebots zu berücksichtigen sein, auch um Effekte auf den Lernerfolg besser bewerten zu können.
Perceived distress, personality characteristics, coping strategies and psychosocial impairments in a national German multicenter cohort of patients with Crohn’s disease and ulcerative colitis
Authors: Petruo Vanessa , Krauss Ekaterina , Kleist Anika , Hardt Juliane , Hake Karsten , Peirano Julia , Krause Thomas , Ehehalt Robert , von Arnauld de la Perriére Philipp , Büning Jürgen , Treml Oliver , Krauss Norbert , Albrecht Heinz , Felten Gisela , Hermannspahn Uta , Burkhardt Ulrike , Eisold Marc , Teich Nils , Siegmund Britta , Maaser Christian , Bokemeyer Bernd , Baumgart Daniel , Neurath Markus , Mudter Jonas ,   German IBD Study Group (GISG) KND
Published: April 2019

Background and aims This study examined differences in personality, psychological distress, and stress coping in inflammatory bowel disease (IBD) depending on type of disease and disease activity. We compared patients suffering from Crohn’s disease (CD) and ulcerative colitis (UC) with controls. While the literature is replete with distinctive features of the pathogenesis of IBD, the specific differences in psychological impairments are not well studied.

Methods In this German national multicenter study, participants were recruited from 32 centers. Two hundred ninety-seven questionnaires were included, delivering vast information on disease status and psychological well-being based on validated instruments with a total of 285 variables.

Results CD patients were more affected by psychological impairments than patients suffering from UC or controls. Importantly, patients with active CD scored higher in neuroticism (p < 0.01), psychological distress (p < 0.001) and maladaptive stress coping (escape, p = 0.03; rumination, p < 0.03), but less need for social support (p = 0.001) than controls. In contrast, patients suffering from active UC showed psychological distress (p < 0.04) and maladaptive coping (avoidance, p < 0.03; escape, p = 0.01). Patients in remission seemed to be less affected. In particular, patients with UC in remission were not inflicted by psychological impairments. The group of CD patients in remission however, showed insecurity (p < 0.01) and paranoid ideation (p = 0.04).

Conclusions We identified specific aspects of psychological impairment in IBD depending on disease and disease activity. Our results underscore the need for psychological support and treatment particularly in active CD.
The “Aachen sings” study (“Aachen choir engagement study into GERD symptoms”): moderate singing and breathing exercises in a choir reduce reflux symptoms – a cohort study in non-specialist choristers
Authors: Dietrich Christoph , Kottmann Tanja , Labenz Joachim , Streetz Konrad , Hellebrandt Peter
Published: April 2019

Background The influence of singing activities and breathing exercises on the presence of gastroesophageal reflux disease (GERD) symptoms is not clear. While an Austrian study found symptom reduction, an Italian study showed more symptoms in professional opera choristers. These contradictory results may be due to differential intensity of the singing exercises. We therefore developed a questionnaire to investigate the presence of GERD typical symptoms and defined GERD in nonprofessional choristers with moderate singing activity and breathing exercises and compared the results to those from related non-singing control persons.

Methods 434 actively engaged lay-choir persons and 310 non-singing friends or relatives answered questions in a questionnaire regarding basic data, singing habits, GERD symptoms, and past or present diagnostic events and medications.

Results Non-singing control persons experienced more frequently heartburn (1.1 ± 4.1 vs. 0.5 ± 1.2 episodes/week, p = 0.001) and acid regurgitation (0.9 ± 4.1 vs. 0.5 ± 1.3 episodes/week, p < 0.001) and had more often already received the diagnosis of GERD (16.8 % vs. 10.4 %, p = 0.011). From the persons without known GERD, members of the control cohort more often fulfilled the simplified diagnostic criteria of GERD (14.3 % vs. 5.1 %, p < 0.001). A multivariate analysis identified non-singing, high body mass index, and smoking as significant risk factors for the presence of GERD symptoms.

Conclusion The frequency of reflux symptoms and GERD is probably still increasing. Moderate singing activities and breathing exercises seem to be helpful in avoiding reflux symptoms such as heartburn and acid regurgitation.
Simultaneous Diagnosis and Treatment of Double Synchronous Spinal Cord Vascular Malformation
Authors: Cannizzaro Delia , Tropeano Maria Pia , Fornari Maurizio , Servadei Franco , Cardia Andrea
Published: April 2019

Although multiple concurrent spinal arteriovenous fistulas (DAVFs) are a well-known anatomical and clinical entity, the management of these lesions and timing of surgical intervention is still a matter of debate.

A 74-year-old man with a 2-year history of progressive weakness of both lower limbs and lower back pain was diagnosed angiographically with a thoracic DAVF. During the surgical procedure, double independent spinal DAVFs were identified. With the aid of neurophysiologic monitoring, we proceeded to the closure of both fistulas in a one-step surgery.

Neurophysiologic monitoring represents a valid, widely available, minimally invasive tool for the detection of immediate motor fiber damage due to disruption of the incorrect vessels during DAVF surgery and facilitates a safe treatment in a one-step procedure.
High speed imaging of solid needle and liquid micro-jet injections
Authors: Oyarte Gálvez Loreto , Brió Pérez Maria , Fernández Rivas David
Published: April 2019

We have used high speed imaging to capture the fast dynamics of two injection methods. The first one and perhaps the oldest known is based on solid needles and used for dermal pigmentation, popularly known as tattooing. The second is a novel needle-free microjet injector based on thermocavitation. Injections in agarose gel skin surrogates were made with both methods and ink formulations having different fluidic properties. Water, a glycerin–water mixture, and commercial inks were used with both injectors to understand better end-point injection. The agarose deformation process due to the solid needle injection helped establish an assessment of penetration potential by using the dimensionless penetration strength quantity. We found that microjet injections are superior than solid injections in terms of energy and volumetric delivery efficiencies per injection for three different liquids. The microjet injector could reduce the environmental impact of used needles and benefit millions of people using needles for medical and cosmetic use.
Elucidating the origins of the two-dimensional electron gas in LaVO3/SrTiO3 interfaces
Authors: Hu L. , Wei R. H. , Tang X. W. , Zhu S. J. , Zhang X. K. , Zhu X. B. , Song W. H. , Dai J. M. , Zhang C. J. , Sun Y. P.
Published: April 2019

The influence of growth rate and substrate temperature on the two-dimensional electron gas (2DEG) of LaVO3/SrTiO3 interfaces has been investigated. It is found that both growth rate and substrate temperature can modulate the structural and electrical properties of the LaVO3/SrTiO3 interfaces through oxygen substrate-to-film transfer. When the LaVO3 thin films are deposited at a low substrate temperature and a high growth rate, the LaVO3/SrTiO3 interfaces exhibit weak oxygen substrate-to-film transfer and resultant low density of oxygen vacancies in the SrTiO3 substrate. As a result, the intrinsic effect (polar discontinuity and/or dielectric screening) dominates the interfacial conduction, while the oxygen vacancies play a minor role. In contrast, the oxygen substrate-to-film transfer (oxygen vacancies in the SrTiO3 substrate) can be enhanced (increased) by depositing the LaVO3 thin films at lower growth rates and/or higher substrate temperatures. In this case, the contribution of oxygen vacancies to the interfacial conduction would prevail over the intrinsic effect. Our results elucidate the origins of 2DEG in the LaVO3/SrTiO3 interfaces and may also be important for other SrTiO3-based heterointerfaces.
A lattice Boltzmann model for squirmers
Authors: Kuron Michael , Stärk Philipp , Burkard Christian , de Graaf Joost , Holm Christian
Published: April 2019

The squirmer is a simple yet instructive model for microswimmers, which employs an effective slip velocity on the surface of a spherical swimmer to describe its self-propulsion. We solve the hydrodynamic flow problem with the lattice Boltzmann (LB) method, which is well-suited for time-dependent problems involving complex boundary conditions. Incorporating the squirmer into LB is relatively straightforward, but requires an unexpectedly fine grid resolution to capture the physical flow fields and behaviors accurately. We demonstrate this using four basic hydrodynamic tests: two for the far-field flow—accuracy of the hydrodynamic moments and squirmer-squirmer interactions—and two that require the near field to be accurately resolved—a squirmer confined to a tube and one scattering off a spherical obstacle—which LB is capable of doing down to the grid resolution. We find good agreement with (numerical) results obtained using other hydrodynamic solvers in the same geometries and identify a minimum required resolution to achieve this reproduction. We discuss our algorithm in the context of other hydrodynamic solvers and present an outlook on its application to multi-squirmer problems.
A kinetic-Monte Carlo perspective on active matter
Authors: Klamser Juliane U. , Kapfer Sebastian C. , Krauth Werner
Published: April 2019

We study non-equilibrium phases for interacting two-dimensional self-propelled particles with isotropic pair-wise interactions using a persistent kinetic Monte Carlo approach. We establish the quantitative phase diagram, including the motility-induced phase separation (MIPS) that is a commonly observed collective phenomenon in active matter. In addition, we demonstrate for several different potential forms the presence of two-step melting, with an intermediate hexatic phase, in regions far from equilibrium. Increased activity can melt a two-dimensional solid and the melting lines remain disjoint from MIPS. We establish this phase diagram for a range of the inter-particle potential stiffnesses and identify the MIPS phase even in the hard-disk limit. We establish that the full description of the phase behavior requires three independent control parameters.
Size dependence of dynamic fluctuations in liquid and supercooled water
Authors: Montes de Oca Joan Manuel , Accordino Sebastián R. , Appignanesi Gustavo A. , Handle Philip H. , Sciortino Francesco
Published: April 2019

We study the evolution of dynamic fluctuations averaged over different space lengths and time scales to characterize spatially and temporally heterogeneous behavior of TIP4P/2005 water in liquid and supercooled states. Analyzing a 250 000 molecules simulated system, we provide evidence of the existence, upon supercooling, of a significant enhancement of spatially localized dynamic fluctuations stemming from regions of correlated mobile molecules. We show that both the magnitude of the departure from the value expected for the system-size dependence of an uncorrelated system and the system size at which such a trivial regime is finally recovered clearly increase upon supercooling. This provides a means to estimate an upper limit to the maximum length scale of influence of the regions of correlated mobile molecules. Notably, such an upper limit grows two orders of magnitude on cooling, reaching a value corresponding to a few thousand molecules at the lowest investigated temperature.
Coins in microfluidics: From mere scale objects to font of inspiration for microchannel circuits
Authors: Pitingolo Gabriele , Taly Valerie , Nastruzzi Claudio
Published: April 2019

The fabrication of microfluidic chips remains a complex and expensive process requiring specific equipment and protocols, often if not always limited to the most privileged laboratories. As an alternative to the most sophisticated methods, the present paper describes the fabrication of microfluidic chips by an approach that uses coins as positive master for the rapid production of multigeometry chips. All steps of chip production were carried out using inexpensive approaches by low-cost chemicals and equipment. The chips were validated by different “classic” microfluidic tasks, such as hydrodynamic focusing, droplets generation, micromixing, and on-chip cell culture. The use of coins is not only an efficient method for rapid prototyping but also represents an inspiring possibility for the design of new microfluidic chips. Finally, coin-inspired chips could represent a laboratory experiment doable at a high school level.
Light-harvesting for high quantum efficiency in InAs-based InAs/GaAsSb type-II superlattices long wavelength infrared photodetectors
Authors: Huang Min , Chen Jianxin , Zhou Yi , Xu Zhicheng , He Li
Published: April 2019

Because of the limited absorption coefficient and undesired reflection loss, it has been a challenge to obtain sufficient light absorption for type-II superlattice (T2SL) long wavelength infrared (LWIR) detectors with a thin thickness. Here, we report a greatly enhanced photon absorption by light harvesting in InAs/GaAsSb T2SLs grown on InAs substrates. High quantum efficiencies (QEs) were first observed in a set of InAs/GaAsSb superlattice LWIR photodetectors with different absorption layer thicknesses. Long minority carrier diffusion lengths are also indicated. However, these high QEs are mainly attributed to the large refractive index difference between the n-doped InAs buffer layer and the SL material, which not only improves the optical path length of incident light by multireflection in the SL material but also reduces the surface reflection by dual-layer thin-film interference at some special wavelengths. By further adjusting the doping concentration of the buffer layer, we achieved a LWIR detector with high QE of more than 60% based on InAs/GaAsSb T2SLs with a thin absorption region thickness of 3.55 μm without any antireflection coating. Our result provides an effective strategy for thin-film detectors to boost their photoresponse, especially for materials with low absorption coefficients.
Dynamically weighted multireference perturbation theory: Combining the advantages of multi-state and state-averaged methods
Authors: Li Chenyang , Lindh Roland , Evangelista Francesco A.
Published: April 2019

We introduce two new approaches to compute near-degenerate electronic states based on the driven similarity renormalization group (DSRG) framework. The first approach is a unitary multi-state formalism based on the DSRG (MS-DSRG), whereby an effective Hamiltonian is built from a set of state-specific solutions. The second approach employs a dynamic weighting parameter to smoothly interpolate between the multi-state and the state-averaged DSRG schemes. The resulting dynamically weighted DSRG (DW-DSRG) theory incorporates the most desirable features of both multi-state approaches (ability to accurately treat many states) and state-averaged methods (correct description of avoided crossings and conical intersections). We formulate second-order perturbation theories (PT2) based on the MS- and DW-DSRG and study the potential energy curves of LiF, the conical intersection of the two lowest singlet states of NH3, and several low-lying excited states of benzene, naphthalene, and anthracene. The DW-DSRG-PT2 predicts the correct avoided crossing of LiF and avoids artifacts produced by the corresponding state-specific and multi-state theories. Excitation energies of the acenes computed with the DW-DSRG-PT2 are found to be more accurate than the corresponding state-averaged values, showing a small dependence on the number of states computed.
Analytic gradient for the QM/MM-Ewald method using charges derived from the electrostatic potential: Theory, implementation, and application to ab initio molecular dynamics simulation of the aqueous electron
Authors: Holden Zachary C. , Rana Bhaskar , Herbert John M.
Published: April 2019

We report an implementation of periodic boundary conditions for mixed quantum mechanics/molecular mechanics (QM/MM) simulations, in which atomic partial charges are used to represent periodic images of the QM region. These charges are incorporated into the Fock matrix in a manner that preserves the variational nature of the self-consistent field procedure, and their interactions with the MM charges are summed using the conventional Ewald technique. To ensure that the procedure is stable in arbitrary basis sets, the atomic charges are derived by least-squares fit to the electrostatic potential generated by the QM region. We formulate and implement analytic energy gradients for the QM/MM-Ewald method and demonstrate that stable molecular dynamics simulations are thereby obtained. As a proof-of-concept application, we perform QM/MM simulations of a hydrated electron in bulk liquid water at the level of Hartree-Fock theory plus empirical dispersion. These simulations demonstrate that the “cavity model” of the aqueous electron, in which the spin density of the anionic defect is localized within an excluded volume in the liquid, is stable at room temperature on a time scale of at least several picoseconds. These results validate cavity-forming pseudopotential models of e−(aq) that have previously been derived from static-exchange Hartree-Fock calculations, and cast doubt upon whether non-cavity-forming pseudopotentials are faithful to the underlying Hartree-Fock calculation from which they were obtained.
Band alignment determination of bulk h-BN and graphene/h-BN laminates using photoelectron emission microscopy
Authors: Ogawa Shuichi , Yamada Takatoshi , Kadowaki Ryo , Taniguchi Takashi , Abukawa Tadashi , Takakuwa Yuji
Published: April 2019

Because graphene stacked on hexagonal boron nitride (h-BN) exhibits high electron mobility, it is expected to be applied to next-generation high-speed transistors and electron emitters. To further improve the performance of graphene/h-BN devices, it is necessary to determine the band alignment of graphene/h-BN laminates. However, because mechanically peeled h-BN single crystals transferred onto Si substrates are small, pinpoint observation of h-BN with ordinary photoelectron spectroscopy is difficult. In this study, the electric structure of a graphene/h-BN laminate was identified by photoemission electron microscopy and local measurements of valence band and secondary electron spectra using micro-ultraviolet photoelectron spectroscopy were performed. From these measurements, we determined the band alignment of a graphene/h-BN laminate with a crystal size of a few tens of micrometers. The work function and electron affinity measured by photoelectron spectroscopy of single-crystal h-BN were 4.6 and −0.5 eV, respectively. Laminating graphene on h-BN caused the Fermi level of h-BN to rise 0.85 eV above that of nonlaminated h-BN. In addition, it was found that graphene on h-BN displayed weak n-type conductivity. The results obtained in this research are expected to be widely applied in the field of electronics such as electron emitters using h-BN with negative electron affinity.
Underwater video surveys provide a more complete picture of littoral fish populations than seine samples in clear Florida springs
Authors: Work Kirsten , Jennings Coramarie Jifu
Published: April 2019

Traditional fish-sampling methods may be problematic because of public use or safety concerns. In this study, we compared one common sampling method with video assessment of fish abundance and diversity in three springs that differed in water clarity and structure. At each of four or five sites per spring, we placed one GoPro camera on each bank for 12min and followed the filming with seine sampling. On the video, we counted the maximum number of individuals of each species observed within one frame (MaxN) and summed these counts to produce an estimate of fish abundance (SumMaxN). Then we compared abundance (SumMaxN), species richness and diversity between seine and video samples across all three springs. Video produced higher estimates of abundance (SumMaxN), species richness, and diversity than did seine sampling. However, this effect was largely confined to species richness and diversity differences between sample methods in the structurally complex spring; differences were subtle or non-existent in the low-structure spring and in the turbid spring. In all three springs, video captured relatively more centrarchids; these taxa were captured only rarely in seine samples. Therefore, video sampling performed as well or better than did seine sampling for fish-assemblage assessment in these clear springs.
The criminogenic and psychological effects of police stops on adolescent black and Latino boys
Authors: Del Toro Juan , Lloyd Tracey , Buchanan Kim S. , Robins Summer Joi , Bencharit Lucy Zhang , Smiedt Meredith Gamson , Reddy Kavita S. , Pouget Enrique Rodriguez , Kerrison Erin M. , Goff Phillip Atiba
Published: April 2019

Significance

Four waves of longitudinal survey data demonstrate that contact with law enforcement predicts increases in black and Latino adolescents’ self-reported criminal behaviors 6, 12, and 18 months later. These results are partially mediated by psychological distress. The younger boys are when stopped for the first time, the stronger these relationships. Boys’ race and prior engagement in delinquent behaviors did not moderate the effect. These findings fill a gap in the research literature on labeling, life course, general strain, and deterrence theories. To our knowledge, the relationships among police contact, psychological strain, and subsequent criminal behavior for young boys had not been tested quantitatively before. These findings raise policy questions about the influence of proactive policing on the trajectory of children.
CAP2 deficiency delays myofibril actin cytoskeleton differentiation and disturbs skeletal muscle architecture and function
Authors: Kepser Lara-Jane , Damar Fidan , De Cicco Teresa , Chaponnier Christine , Prószyński Tomasz J. , Pagenstecher Axel , Rust Marco B.
Published: April 2019

Significance

Displaced myofibrils termed ring fibers have been reported for human congenital myopathies and for myopathies of unknown etiology, but their natural cause largely remained elusive. Cyclase-associated protein 2 (CAP2) is an actin regulator with unknown physiological function. We identified CAP2 as a regulator for the exchange of α-actin isoforms during myofibril differentiation. In CAP2 mutant mice, myofibrils remained in an undifferentiated stage at the onset of excessive voluntary muscle contractions, predisposing them to form ring fibers that compromise skeletal muscle function. Our data confirm that subtle cytoskeletal changes can cause ring fibers. Moreover, they led us to propose that CAP2 inactivation contributes to defects of human 6p22.3 deletion syndrome such as developmental delay and hypotonia.
Fine-scale damage estimates of particulate matter air pollution reveal opportunities for location-specific mitigation of emissions
Authors: Goodkind Andrew L. , Tessum Christopher W. , Coggins Jay S. , Hill Jason D. , Marshall Julian D.
Published: April 2019

Fine particulate matter (PM
2.5
) air pollution has been recognized as a major source of mortality in the United States for at least 25 years, yet much remains unknown about which sources are the most harmful, let alone how best to target policies to mitigate them. Such efforts can be improved by employing high-resolution geographically explicit methods for quantifying human health impacts of emissions of PM
2.5
and its precursors. Here, we provide a detailed examination of the health and economic impacts of PM
2.5
pollution in the United States by linking emission sources with resulting pollution concentrations. We estimate that anthropogenic PM
2.5
was responsible for 107,000 premature deaths in 2011, at a cost to society of $886 billion. Of these deaths, 57% were associated with pollution caused by energy consumption [e.g., transportation (28%) and electricity generation (14%)]; another 15% with pollution caused by agricultural activities. A small fraction of emissions, concentrated in or near densely populated areas, plays an outsized role in damaging human health with the most damaging 10% of total emissions accounting for 40% of total damages. We find that 33% of damages occur within 8 km of emission sources, but 25% occur more than 256 km away, emphasizing the importance of tracking both local and long-range impacts. Our paper highlights the importance of a fine-scale approach as marginal damages can vary by over an order of magnitude within a single county. Information presented here can assist mitigation efforts by identifying those sources with the greatest health effects.
pH dependence, kinetics and light-harvesting regulation of nonphotochemical quenching in
Chlamydomonas
Authors: Tian Lijin , Nawrocki Wojciech J. , Liu Xin , Polukhina Iryna , van Stokkum Ivo H. M. , Croce Roberta
Published: April 2019

Significance

Photosynthetic organisms utilize sunlight as a form of energy. Under low light, they maximize their capacity to harvest photons; however, under excess light, they dissipate part of the harvested energy to prevent photodamage, at the expense of light-use efficiency. Optimally balancing light harvesting and energy dissipation in natural (fluctuating light) conditions is considered a target for improving the productivity of both algae and plants. Here we have studied the energy dissipation process in the green alga
Chlamydomonas reinhardtii
in vivo. We found that it is remarkably different from that of higher plants, highlighting the need of developing tailor-made strategies to optimize the light harvesting–energy dissipation balance in different organisms.
Prediction and identification of recurrent genomic rearrangements that generate chimeric chromosomes in
Saccharomyces cerevisiae
Authors: Palacios-Flores Kim , Castillo Alejandra , Uribe Carina , García Sotelo Jair , Boege Margareta , Dávila Guillermo , Flores Margarita , Palacios Rafael , Morales Lucia
Published: April 2019

Significance

Genome dynamics has implications in different biological phenomena, including pathological and evolutionary processes. Nonallelic homologous recombination generates genomic rearrangements mediated by long repeated sequences with high identity. By locating repeated regions shared by two different chromosomes along the genome of the yeast
Saccharomyces cerevisiae
, we predicted rearrangements that generate chimeric chromosomes. A PCR-based strategy revealed the chimeric structures predicted. The alignment of the nucleotide sequence of the PCR products to the genome ascertained the expected origin of the chimeric structures. Such structures were found in the culture and in colonies isolated from single cells. Our findings indicate that interchromosomal rearrangements that generate chimeric chromosomes are recurrent and occur, at a relatively high frequency, in cell populations of
S. cerevisiae
.
Processing of prompt gamma-ray timing data for proton range measurements at a clinical beam delivery
Authors: Werner Theresa , Berthold Jonathan , Hueso-González Fernando , Koegler Toni , Petzoldt Johannes , Roemer Katja , Richter Christian , Rinscheid Andreas , Straessner Arno , Enghardt Wolfgang , Pausch Guntram
Published: April 2019

In proton therapy, patients benefit from the precise deposition of the dose in the tumor volume due to the interaction of charged particles with matter. Currently, the determination of the beam range in the patient’s body during the treatment is not a clinical standard. This lack causes broad safety margins around the tumor, which limits the potential of proton therapy. To overcome this obstacle, different methods are under investigation aiming at the verification of the proton range in real time during the irradiation. One approach is the prompt gamma-ray timing (PGT) method, where the range of the primary protons is derived from time-resolved profiles (PGT spectra) of promptly emitted gamma rays, which are produced along the particle track in tissue. After verifying this novel technique in an experimental environment but far away from treatment conditions, the translation of PGT into clinical practice is intended. Therefore, new hardware was extensively tested and characterized using short irradiation times of 70 ms and clinical beam currents of 2 nA. Experiments were carried out in the treatment room of the University Proton Therapy Dresden. A pencil beam scanning plan was delivered to a target without and with cylindrical air cavities of down to 5 mm thickness. The range shifts of the proton beam induced due to the material variation could be identified from the corresponding PGT spectra, comprising events collected during the delivery of a whole energy layer. Additionally, an assignment of the PGT data to the individual pencil beam spots allowed a spot-wise analysis of the variation of the PGT distribution mean and width, corresponding to range shifts produced by the different air cavities. Furthermore, the paper presents a comprehensive software framework which standardizes future PGT analysis methods and correction algorithms for technical limitations that have been encountered in the presented experiments.
Interaction Analysis Investigations of Multiple Supply Duct Split-type Air-conditioning units in an Open Space
Authors: Widsonkun W , Woradechjumroen D , Vongbunyong S
Published: April 2019

Oversizing has been seldom concerning in Thailand. However, oversizing causes short-term operations of an air-conditioning (AC) unit and excessive power consumptions. In addition, multiple operations of oversized AC units can be faulty operations when they are used to serve in an open space area because interaction among AC units are not considered before installations. This paper collects data operations of the multiple supply duct split-type air-conditioning (SAC) units used in an open space from additional sensors installed in zone and return temperature. Significant wireless sensors are added for measuring temperature effect among a interaction area between two SAC units. To measure the system variation caused by system interaction, runtime fraction (RTF) is used to quantify the compressor runtime ratio which equals to a stage-on time operation over the cycle time at an AC design condition. The results show that one of the four SAC units performs under-sizing instead of oversizing performance because it runs continuously without off cycling. To diagnose this issue, interactions between zone and return temperature are quantified in terms of correlation coefficient, which demonstrates that this SAC results in higher oversizing of the rest SAC units. This interaction analysis can be further used to design a soft-repair algorithm to reduce oversizing effect of the multiple SAC operations.
Heat Transfer Augmentation in Round Tube with Diamond-shaped Baffle Inserts
Authors: Khanoknaiyakarn C. , Sripattanapipat S. , Promvonge P. , Skullong S.
Published: April 2019

Influences of diamond-shaped baffle (DSB) insertion in a heat exchanger tube on its thermal performance are experimentally presented. The DSB elements were repeatedly mounted into the tube using two straight small rods to connect the DSBs together to produce the longitudinal vortex flows inside. The experiments were carried out in a constant surface heat-fluxed tube equiped with DSBs. The DSBs were placed periodically with an attack angle of 45° and a pitch spacing of three times of tube diameter (PR=P/D=3) while four different DSB heights called blockage ratios (BR=b/D=0.1, 0.2, 0.3 and 0.4) were offered. Air was used as the test fluid flowed into the tube to yield the Reynolds number (Re) in a range of 4190-26,000. The heat transfer rate and the pressure drop of the current work were presented in terms of Nusselt number (Nu) and friction factor (f), respectively. The experimental results showed that the DSB provides the increase in the heat transfer around 3.53-4.16 times higher than the smooth tube while friction factor increases around 16.68-29.52 times. To evaluate the gain of using the DSB, the thermal performance factor (TEF) is determined in a range of 1.25-1.55 whereas the highest TEF is found at BR=0.1.
Patterns of emergency department attendance among older people in the last three months of life and factors associated with frequent attendance: a mortality follow-back survey
Authors: Bone Anna E , Evans Catherine J , Henson Lesley A , Gao Wei , Higginson Irene J ,   BUILDCARE study
Published: April 2019

Background

frequent emergency department (ED) attendance at the end of life disrupts care continuity and contradicts most patients’ preference for home-based care.

Objective

to examine factors associated with frequent (≥3) end of life ED attendances among older people to identify opportunities to improve care.

Methods

pooled data from two mortality follow-back surveys in England. Respondents were family members of people aged ≥65 who died four to ten months previously. We used multivariable modified Poisson regression to examine illness, service and sociodemographic factors associated with ≥3 ED attendances, and directed content analysis to explore free-text responses.

Results

688 respondents (responses from 42.0%); most were sons/daughters (60.5%). Mean age at death was 85 years. 36.5% had a primary diagnosis of cancer and 16.3% respiratory disease. 80/661 (12.1%) attended ED ≥3 times, accounting for 43% of all end of life attendances. From the multivariable model, respiratory disease (reference cancer) and ≥2 comorbidities (reference 0) were associated with frequent ED attendance (adjusted prevalence ratio 2.12, 95% CI 1.21–3.71 and 1.81, 1.07–3.06). Those with ≥7 community nursing contacts (reference 0 contacts) were more likely to frequently attend ED (2.65, 1.49–4.72), whereas those identifying a key health professional were less likely (0.58, 0.37–0.88). Analysis of free-text found inadequate community support, lack of coordinated care and untimely hospital discharge were key issues.

Conclusions

assigning a key health professional to older people at increased risk of frequent end of life ED attendance, e.g. those with respiratory disease and/or multiple comorbidities, may reduce ED attendances by improving care coordination.
A Novel Frameshift Mutation of SCNN1G Causing Liddle Syndrome with Normokalemia
Authors: Fan Peng , Zhao Yu-Mo , Zhang Di , Liao Ying , Yang Kun-Qi , Tian Tao , Lou Ying , Luo Fang , Ma Wen-Jun , Zhang Hui-Min , Song Lei , Cai Jun , Liu Ya-Xin , Zhou Xian-Liang
Published: April 2019

BACKGROUND

Liddle syndrome (LS) is an autosomal dominant disorder caused by single-gene mutations of the epithelial sodium channel (ENaC). It is characterized by early-onset hypertension, spontaneous hypokalemia and low plasma renin and aldosterone concentrations. In this study, we reported an LS pedigree with normokalemia resulting from a novel SCNN1G frameshift mutation.

METHODS

Peripheral blood samples were collected from the proband and eight family members for DNA extraction. Next-generation sequencing and Sanger sequencing were performed to identify the SCNN1G mutation. Clinical examinations were used to comprehensively evaluate the phenotypes of two patients.

RESULTS

Genetic analysis identified a novel SCNN1G frameshift mutation, p.Arg586Valfs*598, in the proband with LS. This heterozygous frameshift mutation generated a premature stop codon and deleted the vital PY motif of ENaC. The same mutation was present in his elder brother with LS, and his mother without any LS symptoms. Biochemical examination showed normokalemia in the three mutation carriers. The mutation identified was not found in any other family members, 100 hypertensives, or 100 healthy controls.

CONCLUSIONS

Our study identified a novel SCNN1G frameshift mutation in a Chinese family with LS, expanding the genetic spectrum of SCNN1G. Genetic testing helped us identify LS with a pathogenic mutation when the genotypes and phenotype were not completely consistent because of the hypokalemia. This case emphasizes that once a proband is diagnosed with LS by genetic testing, family genetic sequencing is necessary for early diagnosis and intervention for other family members, to protect against severe cardiovascular complications.
Premaxillary Injection for Perioral Rejuvenation and Lip Enhancement
Authors: Ho Thuy-Van T , Cerrati Eric W , Gandhi Nimit D , Kalbag Arjun , Dayan Steven H
Published: April 2019

Background

This is the first study to evaluate the effect of premaxillary filler injection on nasal tip projection, upper lip projection, and upper lip vermilion height.

Objectives

The primary objective of this study was to analyze the change in nasal tip projection (measured by the Goode ratio) and the change in upper lip projection (measured by the Z angle) following premaxillary hyaluronic acid injection. A secondary objective was to measure the change in upper lip vermilion height. We hypothesized that treated subjects will show an increase in nasal tip projection, upper lip projection, and upper lip vermilion height.

Methods

Twenty volunteer patients with signs of perioral aging or poor upper lip projection were enrolled in this prospective cohort study and underwent premaxillary hyaluronic acid filler injection between November 2017 and June 2018. Nasal tip projection, upper lip projection, and upper lip vermilion height were assessed from baseline and posttreatment photographs based on the Goode ratio, Z angle, and lip vermilion height ratio, respectively.

Results

No significant change was noted between pre- and posttreatment Goode ratio measurements (P = 0.841). There was a significant decrease in Z angle and therefore significant increase in upper lip projection with treatment (P < 0.001). The lip vermilion height ratio demonstrated a trend of increased upper lip vermilion height but this did not achieve statistical significance (P = 0.561).

Conclusions

Premaxillary filler treatment resulted in a significant increase in upper lip projection. Premaxillary filler injection when performed in a safe manner is a valuable treatment option for perioral rejuvenation.

Level of Evidence: 4
Revised phylogeography of the common whelk Buccinum undatum (Gastropoda: Buccinidae) across the North Atlantic
Authors: Magnúsdóttir Hildur , Pálsson Snæbjörn , Westfall Kristen Marie , Jónsson Zophonías O , Goodall Jake , Örnólfsdóttir Erla Björk
Published: April 2019

The purpose of this study was to revisit the mitochondrial genetic divergence of North Atlantic populations of the subtidal gastropod Buccinum undatum, because previous mitochondrial DNA (mtDNA) analysis by Pálsson et al. (2014) included 16S ribosomal RNA sequences that were incorrectly assigned to the species. In the present study, population mtDNA variation is now assessed using COI sequences obtained from previous research (Pálsson et al., 2014) and, to increase the geographical cover of the study, data from recently assembled transcriptomes of 96 Icelandic whelks (Jónsson et al., 2019) and GenBank are also used. To estimate the mtDNA divergence in B. undatum across the North Atlantic, two species screening indices were used: automatic barcode gap discovey (ABGD; Puillandre et al., 2012a) and species screening threshold index (SSTI; Witt et al., 2006). Phylogenetic reconstruction revealed monophyletic Eastern and Western North Atlantic whelk lineages, which diverged early in the Pleistocene glaciation (2.1 Mya), followed by a subsequent divergence event between Greenlandic and Canadian populations at 1.3 Mya. Species screening indices, ABGD and SSTI, indicated cryptic speciation or allopatric divergence. Genetic distances between populations from the two continents were similar to or greater than interspecific genetic distances across several North Pacific and North Atlantic Buccinum species.
Presynaptic dopamine deficit in minimally conscious state patients following traumatic brain injury
Authors: Fridman Esteban A , Osborne Joseph R , Mozley Paul D , Victor Jonathan D , Schiff Nicholas D
Published: April 2019

Dopaminergic stimulation has been proposed as a treatment strategy for post-traumatic brain injured patients in minimally conscious state based on a clinical trial using amantadine, a weak dopamine transporter blocker. However, a specific contribution of dopaminergic neuromodulation in minimally conscious state is undemonstrated. In a phase 0 clinical trial, we evaluated 13 normal volunteers and seven post-traumatic minimally conscious state patients using 11C-raclopride PET to estimate dopamine 2-like receptors occupancy in the striatum and central thalamus before and after dopamine transporter blockade with dextroamphetamine. If a presynaptic deficit was observed, a third and a fourth 11C-raclopride PET were acquired to evaluate changes in dopamine release induced by l-DOPA and l-DOPA+dextroamphetamine. Permutation analysis showed a significant reduction of dopamine release in patients, demonstrating a presynaptic deficit in the striatum and central thalamus that could not be reversed by blocking the dopamine transporter. However, administration of the dopamine precursor l-DOPA reversed the presynaptic deficit by restoring the biosynthesis of dopamine from both ventral tegmentum and substantia nigra. The advantages of alternative pharmacodynamic approaches in post-traumatic minimally conscious state patients should be tested in clinical trials, as patients currently refractory to amantadine might benefit from them.