bluuebunny/crossref_metadata_2025 huggingface dataset:
Magnetic orbital motion and 0.5e2/h conductance of quantum-anomalous-Hall hybrid strips
Authors: Osca Javier , Serra Llorenç
Published: April 2019

The magnetic-induced orbital motion of quasiparticles affects the conductance properties of a hybrid strip of a quantum-anomalous-Hall topological material with induced superconductivity. We elucidate the scenario of topological normal-superconducting-normal ideal junctions in the presence of orbital magnetic motion, showing how it leads to a halved quantized conductance 0.5e2/h even in the absence of Majorana modes. For vanishing energy, the magnetic orbital effect favors Fermionic charged modes with finite wave numbers, in contrast to chiral Majorana modes that are chargeless modes with the vanishing wave number. The bias sensitivity of the 0.5 conductance plateau allows distinguishing the two cases. Conductance oscillations due to backscattering interference are absent in the charged Fermion case.
Theoretical study of electronic properties of gold fullerenes Au16–Au20
Authors: Mironov G. I.
Published: April 2019

A theoretical study of gold fullerenes Au16–Au20 as strongly correlated electron systems is carried out within the framework of the Hubbard model in the approximation of static fluctuations. The Fourier transforms of anticommutator Green’s functions for electrons at different fullerene sites of gold atoms are obtained and energy spectra are constructed. The density of electron states, the graphical depiction of the equation for the chemical potential, thermodynamic averages characterizing electron transitions among adjacent sites and the description of the probabilities of detecting two electrons with oppositely oriented spin projections on a single site within nanosystems are presented and analyzed. The considered gold fullerenes are demonstrated to possess semiconductor properties.
IR Spectrometry studies of methanol cryovacuum condensates
Authors: Drobyshev A. , Aldiyarov A. , Sokolov D. , Shinbaeva A. , Nurmukan A.
Published: April 2019

This article details the results of IR spectrometric studies on methanol cryovacuum condensates formed on a metal mirror at temperatures between 16–130 K. The vibrational spectra of gaseous methanol are compared to that of methanol condensed into the solid state. It is shown that the vibrational spectra have a significant dependence on the samples’ history and subsequent changes in temperature. Analysis of the obtained spectra allows for the determination of the temperature at which the glassy state (GS) transitions to the supercooled liquid (SCL) state, Tg = 102.6 K. The temperature range in which the SCL state exists is identified as 103–118 K, and the temperature range in which the SCL crystallizes, is found to be 118–120 K.
High pressure-induced relaxation of electrical resistance in weakly doped НоBa2Cu3O7–x single crystals
Authors: Khadzhai G. Ya. , Vovk R. V.
Published: April 2019

The relaxation of high-temperature resistance, ρ(300 K t), in HoBa2Cu3O7–x single crystals after a sharp change in hydrostatic pressure is investigated. A comparison of the electrical resistance relaxation against the relaxation of the superconducting transition critical temperature Тс under the same experimental conditions points to the existence of anisotropy in vacancy cluster relaxation: cluster coalescence is dominant in the Сu–О planes; however, the generation of new clusters and coalescence of existing clusters both occur in the sample volume.
Lifetime prevalence of exostoses in New Zealand surfers
Authors: Simas Vini , Remnant Debbie , Furness James , Bacon Catherine J. , Moran Robert W. , Hing Wayne A. , Climstein Mike
Published: April 2019

ABSTRACT
INTRODUCTIONExternal auditory exostosis (EAE) is a benign, irreversible bony outgrowth that arises from the temporal bone. EAE projects into the external ear canal, potentially causing recurrent otitis externa and conductive hearing loss.
AIMTo determine lifetime prevalence of EAE in New Zealand (NZ) surfers.
METHODSThis study used an online national survey.
RESULTSRespondents were 1376 NZ surfers (recreational = 868, competitive = 508). Mean surfing experience was 16.2 years. Most self-classified as advanced surfers (36.5%), followed by intermediate (30.2%), expert (20.1%) and beginner (13.2%). Surfers reported an average of 214.2 h surfing (28.6% during winter) for the previous year. Overall lifetime prevalence of EAE was 28.9% (32.1% male, 14.6% female; P < 0.001), with the highest proportion of EAE was observed bilaterally (21.3%). Competitive surfers reported a significantly (P < 0.001) higher lifetime prevalence of EAE than recreational surfers (45.3% vs. 19.2%). A significantly higher (P < 0.001) lifetime prevalence of EAE was identified as skill level increased (7.1% in beginners to 55.6% in experts) and a two-fold increase (P < 0.001) of EAE in the highest (vs. lowest) quartile of surfing exposure. Neither winter surfing exposure nor which Island surfed were associated with EAE prevalence.
DISCUSSIONAlthough not as prevalent as in previous NZ research using otologic examinations, this study indicated that almost one-third of NZ surfers reported having had a diagnosis of EAE. Regular general practitioner otologic assessment and advice on appropriate prevention strategies for patients who surf may help prevent large lesions, recurrent ear infections and progressive hearing loss.
Link between molecular mobility and order parameter during liquid–liquid transition of a molecular liquid
Authors: Murata Ken-ichiro , Tanaka Hajime
Published: April 2019

Significance

Contrary to a common sense that a liquid state is unique for a pure system, there have been a number of indications for the presence of more than two liquid states. The transition between the liquid states is called “liquid–liquid transition.” There has so far been little information on how local molecular dynamics changes during the transformation. Here, we reveal the correlation between the order parameter and molecular dynamics by real-time dielectric spectroscopy measurements during the transformation from liquid I to liquid II in a molecular liquid, triphenyl phosphite. Our results suggest that the local order parameter controls local dynamics. Our finding sheds light on the nature of liquid–liquid transition from a perspective of molecular-level dynamics.
Porosity analysis of superfine-grain graphite IG-110 and ultrafine-grain graphite T220
Authors: Huang Qing , Tang Hui
Published: April 2019

Gas-escape pores in nuclear graphite IG-110 and T220 were characterized by using optical microscopy. It is proved that reliable size distribution of pores can be derived by processing optical images of graphite. The results were compared with those obtained from mercury porosimetry test and X-ray tomography. Optical microscopy showed that the majority of IG-110's (T220's) porosity is contributed by pores with sizes around 13 (3) µm, which was confirmed by X-ray tomography for IG-110. But, mercury porosimetry test indicated that pores with sizes around 2.3 (0.9) µm contribute the majority of IG-110's (T220's) porosity. The difference between mercury porosimetry and the other two techniques suggests that the graphite pores are connected by relatively thinner channels.
Modeling meiotic chromosome pairing: a tug of war between telomere forces and a pairing-based Brownian ratchet leads to increased pairing fidelity
Authors: Marshall Wallace F , Fung Jennifer C
Published: April 2019

Meiotic homolog pairing involves associations between homologous DNA regions scattered along the length of a chromosome. When homologs associate, they tend to do so by a processive zippering process, which apparently results from avidity effects. Using a computational model, we show that this avidity-driven processive zippering reduces the selectivity of pairing. When active random forces are applied to telomeres, this drop in selectivity is eliminated in a force-dependent manner. Further simulations suggest that active telomere forces are engaged in a tug-of-war against zippering, which can be interpreted as a Brownian ratchet with a stall force that depends on the dissociation constant of pairing. When perfectly homologous regions of high affinity compete with homeologous regions of lower affinity, the affinity difference can be amplified through this tug of war effect provided the telomere force acts in a range that is strong enough to oppose zippering of homeologs while still permitting zippering of correct homologs. The degree of unzippering depends on the radius of the nucleus, such that complete unzippering of homeologous regions can only take place if the nucleus is large enough to pull the two chromosomes completely apart. A picture of meiotic pairing thus emerges that is fundamentally mechanical in nature, possibly explaining the purpose of active telomere forces, increased nuclear diameter, and the presence of ‘Maverick’ chromosomes in meiosis.
Ultrasound-assisted biofabrication and bioprinting of preferentially aligned three-dimensional cellular constructs
Authors: Chansoria Parth , Narayanan Lokesh Karthik , Schuchard Karl , Shirwaiker Rohan
Published: April 2019

A critical consideration in tissue engineering is to recapitulate the microstructural organization of native tissues that is essential to their function. Scaffold-based techniques have focused on achieving this via the contact guidance principle wherein topographical cues offered by scaffold fibers direct migration and orientation of cells to govern subsequent cell-secreted extracellular matrix organization. Alternatively, approaches based on acoustophoretic, electrophoretic, photophoretic, magnetophoretic, and chemotactic principles are being investigated in the biofabrication domain to direct patterning of cells within bioink constructs. This work describes a new acoustophoretic three-dimensional (3D) biofabrication approach that utilizes radiation forces generated by superimposing ultrasonic bulk acoustic waves (BAW) to preferentially organize cellular arrays within single and multi-layered hydrogel constructs. Using multiphysics modeling and experimental design, we have characterized the effects of process parameters including ultrasound frequency (0.71, 1, 1.5, 2 MHz), signal voltage amplitude (100, 200 mVpp), bioink viscosity (5, 70 cP), and actuation duration (10, 20 min) on the alignment characteristics, viability and metabolic activity of human adipose-derived stem cells (hASC) suspended in alginate. Results show that the spacing between adjacent cellular arrays decreased with increasing frequency (p < 0.001), while the width of the arrays decreased with increasing frequency and amplitude (p < 0.05), and upon lowering the bioink viscosity (p < 0.01) or increasing actuation duration (p < 0.01). Corresponding to the computational results wherein estimated acoustic radiation forces demonstrated a linear relationship with amplitude and a nonlinear relationship with frequency, the interaction of moderate frequencies at high amplitudes resulted in viscous perturbations, ultimately affecting the hASC viability (p < 0.01). For each combination of frequency and amplitude at the extremities of the tested range, the hASC metabolic activity did not change over 4 d, but the activity of the low frequency-high amplitude treatment was lower than that of the high frequency-low amplitude treatment at day 4 (p < 0.01). In addition to this process-structure characterization, we have also demonstrated the 3D bioprinting of a multi-layered medial knee meniscus construct featuring physiologically-relevant circumferential organization of viable hASC. This work contributes to the advancement of scalable biomimetic tissue manufacturing science and technology.
Remarks on the derivation of finite energy weak solutions to the QHD system
Authors: Antonelli Paolo
Published: April 2019

In this note we give an alternative proof of existence of finite energy weak solutions to the quantum hydrodynamics (QHD) system. The main novelty in our approach is that no regularization procedure or approximation is needed, as it is only based on the integral formulation of NLS equation and the a priori bounds given by the Strichartz estimates. The main advantage of this proof is that it can be applied to a wider class of QHD systems.
Mixed ray transform on simple 2-dimensional Riemannian manifolds
Authors: de Hoop Maarten , Saksala Teemu , Zhai Jian
Published: April 2019

We characterize the kernel of the mixed ray transform on simple

2
2

-dimensional Riemannian manifolds, that is, on simple surfaces for tensors of any order.
Cargo Preference and U.S. International Food Aid Programs
Authors: Mercier Stephanie , Smith Vincent
Published: April 2019

The United States is the world's largest donor of humanitarian assistance. However, that aid's effectiveness is hampered by decades‐old rules that restrict where food aid commodities are purchased and how they are transported to recipient countries. This paper evaluates costs associated with one of those restrictions—food aid cargo preference—which requires that at least half of all U.S. food aid shipped in a given year be carried on U.S.‐flagged vessels. The empirical analysis presented in this study, based on individual food aid shipments between January 2012 and May 2015, indicates that cargo preference added $42 million annually to program costs.
Acute and midterm outcomes of the post-approval MELODY Registry: a multicentre registry of transcatheter pulmonary valve implantation
Authors: Nordmeyer Johannes , Ewert Peter , Gewillig Marc , AlJufan Mansour , Carminati Mario , Kretschmar Oliver , Uebing Anselm , Dähnert Ingo , Röhle Robert , Schneider Heike , Witsenburg Maarten , Benson Lee , Gitter Roland , Bökenkamp Regina , Mahadevan Vaikom , Berger Felix
Published: April 2019

Aims

The post-approval MELODY Registry aimed to obtain multicentre registry data after transcatheter pulmonary valve implantation (TPVI) with the Melody™ valve (Medtronic plc.) in a large-scale cohort of patients with congenital heart disease (CHD).

Methods and results

Retrospective analysis of multicentre registry data after TPVI with the Melody™ valve. Eight hundred and forty-five patients (mean age: 21.0 ± 11.1 years) underwent TPVI in 42 centres between December 2006 and September 2013 and were followed-up for a median of 5.9 years (range: 0–11.0 years). The composite endpoint of TPVI-related events during follow-up (i.e. death, reoperation, or reintervention >48 h after TPVI) showed an incidence rate of 4.2% per person per year [95% confidence interval (CI) 3.7–4.9]. Transcatheter pulmonary valve implantation infective endocarditis (I.E.) showed an incidence rate of 2.3% per person per year (95% CI 1.9–2.8) and resulted in significant morbidity and in nine deaths. In multivariable Cox proportional hazard models, the invasively measured residual right ventricle (RV)-to-pulmonary artery (PA) pressure gradient (per 5 mmHg) was associated with the risk of the composite endpoint (adjusted hazard ratio: 1.21, 95% CI 1.12–1.30; P < 0.0001) and the risk of TPVI I.E. (adjusted hazard ratio: 1.19, 95% CI 1.07–1.32; P = 0.002). Major procedural complications (death, surgical, or interventional treatment requirement) occurred in 0.5%, 1.2%, and 2.0%, respectively. Acutely, the RV-to-PA pressure gradient and the percentage of patients with pulmonary regurgitation grade >2 improved significantly from 36 [interquartile range (IQR) 24–47] to 12 (IQR 7–17) mmHg and 47 to 1%, respectively (P < 0.001 for each).

Conclusion

The post-approval MELODY Registry confirms the efficacy of TPVI with the Melody™ valve in a large-scale cohort of CHD patients. The residual invasively measured RV-to-PA pressure gradient may serve as a target for further improvement in the composite endpoint and TPVI I.E. However, TPVI I.E. remains a significant concern causing significant morbidity and mortality.
Serum metabolic signatures of coronary and carotid atherosclerosis and subsequent cardiovascular disease
Authors: Tzoulaki Ioanna , Castagné Raphaële , Boulangé Claire L , Karaman Ibrahim , Chekmeneva Elena , Evangelou Evangelos , Ebbels Timothy M D , Kaluarachchi Manuja R , Chadeau-Hyam Marc , Mosen David , Dehghan Abbas , Moayyeri Alireza , Ferreira Diana L Santos , Guo Xiuqing , Rotter Jerome I , Taylor Kent D , Kavousi Maryam , de Vries Paul S , Lehne Benjamin , Loh Marie , Hofman Albert , Nicholson Jeremy K , Chambers John , Gieger Christian , Holmes Elaine , Tracy Russell , Kooner Jaspal , Greenland Philip , Franco Oscar H , Herrington David , Lindon John C , Elliott Paul
Published: April 2019

Aims

To characterize serum metabolic signatures associated with atherosclerosis in the coronary or carotid arteries and subsequently their association with incident cardiovascular disease (CVD).

Methods and results

We used untargeted one-dimensional (1D) serum metabolic profiling by proton nuclear magnetic resonance spectroscopy (1H NMR) among 3867 participants from the Multi-Ethnic Study of Atherosclerosis (MESA), with replication among 3569 participants from the Rotterdam and LOLIPOP studies. Atherosclerosis was assessed by coronary artery calcium (CAC) and carotid intima-media thickness (IMT). We used multivariable linear regression to evaluate associations between NMR features and atherosclerosis accounting for multiplicity of comparisons. We then examined associations between metabolites associated with atherosclerosis and incident CVD available in MESA and Rotterdam and explored molecular networks through bioinformatics analyses. Overall, 30 1H NMR measured metabolites were associated with CAC and/or IMT, P = 1.3 × 10−14 to 1.0 × 10−6 (discovery) and P = 5.6 × 10−10 to 1.1 × 10−2 (replication). These associations were substantially attenuated after adjustment for conventional cardiovascular risk factors. Metabolites associated with atherosclerosis revealed disturbances in lipid and carbohydrate metabolism, branched chain, and aromatic amino acid metabolism, as well as oxidative stress and inflammatory pathways. Analyses of incident CVD events showed inverse associations with creatine, creatinine, and phenylalanine, and direct associations with mannose, acetaminophen-glucuronide, and lactate as well as apolipoprotein B (P < 0.05).

Conclusion

Metabolites associated with atherosclerosis were largely consistent between the two vascular beds (coronary and carotid arteries) and predominantly tag pathways that overlap with the known cardiovascular risk factors. We present an integrated systems network that highlights a series of inter-connected pathways underlying atherosclerosis.
Research with Agricultural Animals and Wildlife
Authors: Cox Rebecca J , Nol Pauline , Ellis Christine K , Palmer Mitchell V
Published: April 2019

In fiscal year 2016, agricultural animals such as swine, sheep, goats, and cattle represented 10% of the 820 812 animals used in USDA-regulated research. In addition to traditional agricultural animals, research studies using captive wildlife are becoming increasingly important as human and livestock populations encroach upon, and thus expand interactions with, wildlife populations on the landscape. Optimum healthcare of both livestock and captive wildlife in a research setting requires proper husbandry, management, and veterinary care. Regardless of animal species, proper care and management are essential for animal well-being, valid research data, and the health and safety of animal care personnel. Using wildlife in research presents unique challenges as there is generally limited peer-reviewed research on wildlife welfare, husbandry, and nutrition. Animals often become excited during handling or transport, and care must be taken to avoid injury. When severe injuries do occur, differences may exist in methods of euthanasia. Many wildlife species are evolutionarily programmed to conceal signs of illness, making assessment of their condition difficult; moreover, attending veterinarians are often not as experienced in the care of wildlife as they are in the care of traditional laboratory animals or livestock. These differences are further magnified in the context of wildlife field research. The concepts of replace, reduce, and refine are as valid in livestock and wildlife research as in biomedical research, and investigators should work closely with their Institutional Animal Care and Use Committees to ensure humane animal care. The Institutional Animal Care and Use Committee is centrally important in providing guidelines relative to ethical use of animal subjects for research and can serve as a valuable resource for research accountability.
Early Clearance of Mycobacterium tuberculosis Is Associated With Increased Innate Immune Responses
Authors: Verrall Ayesha J , Schneider Marion , Alisjahbana Bachti , Apriani Lika , van Laarhoven Arjan , Koeken Valerie A C M , van Dorp Suszanne , Diadani Emira , Utama Fitri , Hannaway Rachel F , Indrati Agnes , Netea Mihai G , Sharples Katrina , Hill Philip C , Ussher James E , van Crevel Reinout
Published: April 2019

Background

A proportion of tuberculosis (TB) case contacts do not become infected, even when heavily exposed. We studied the innate immune responses of TB case contacts to understand their role in protection against infection with Mycobacterium tuberculosis, termed “early clearance.”

Methods

Indonesian household contacts of TB cases were tested for interferon-γ release assay (IGRA) conversion between baseline and 14 weeks post recruitment. Blood cell populations and ex vivo innate whole blood cytokine responses were measured at baseline and, in a subgroup, flow cytometry was performed at weeks 2 and 14. Immunological characteristics were measured for early clearers, defined as a persistently negative IGRA at 3 months, and converters, whose IGRA converted from negative to positive.

Results

Among 1347 case contacts, 317 were early clearers and 116 were converters. Flow cytometry showed a resolving innate cellular response from 2 to 14 weeks in persistently IGRA-negative contacts but not converters. There were no differences in cytokine responses to mycobacterial stimuli, but compared to converters, persistently IGRA-negative contacts produced more proinflammatory cytokines following heterologous stimulation with Escherichia coli and Streptococcus pneumoniae.

Conclusions

Early clearance of M. tuberculosis is associated with enhanced heterologous innate immune responses similar to those activated during induction of trained immunity.
Uniform interpolation for propositional and modal team logics
Authors: D’Agostino Giovanna
Published: April 2019

In this paper we consider modal team logic, a generalization of classical modal logic in which it is possible to describe dependence phenomena between data. We prove that most known fragments of full modal team logic allow the elimination of the so called ‘existential bisimulation quantifiers’, where the existence of a certain set is required only modulo bisimulation (i.e. not in the model itself but possibly in a bisimilar model). As a consequence, we prove that these fragments enjoy the uniform interpolation property.
The Impact of Concomitant Empiric Cefepime on Patient Outcomes of Methicillin-Resistant Staphylococcus aureus Bloodstream Infections Treated With Vancomycin
Authors: Zasowski Evan J , Trinh Trang D , Atwan Safana M , Merzlyakova Marina , Langf Abdalhamid M , Bhatia Sahil , Rybak Michael J
Published: April 2019

Background

Data suggest that vancomycin + β-lactam combinations improve clearance of methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infections (BSIs). However, it is unclear which specific β-lactams confer benefit. This analysis evaluates the impact of concomitant empiric cefepime on outcomes of MRSA BSIs treated with vancomycin.

Methods

Retrospective cohort study of adults with MRSA BSI from 2006 to 2017. Vancomycin + cefepime therapy was defined as ≥24 hours of cefepime during the first 72 hours of vancomycin. The primary outcome was microbiologic failure, defined as BSI duration ≥7 days and/or 60-day recurrence. Multivariable logistic regression was used to evaluate the association between vancomycin + cefepime therapy and binary outcomes. Cause-specific and subdistribution hazard models were used to evaluate the association between vancomycin + cefepime and BSI clearance.

Results

Three hundred fifty-eight patients were included, 129 vancomycin and 229 vancomycin + cefepime. Vancomycin + cefepime therapy was independently associated with reduced microbiologic failure (adjusted odds ratio [aOR], 0.488; 95% confidence interval [CI], 0.271–0.741). This was driven by a reduction in the incidence of BSI durations ≥7 days (vancomycin + cefepime aOR, 0.354; 95% CI, 0.202–0.621). Vancomycin + cefepime had no association with 30-day mortality (aOR, 0.952; 95% CI, 0.435–2.425). Vancomycin + cefepime was associated with faster BSI clearance in both cause-specific (HR, 1.408; 95% CI, 1.125–1.762) and subdistribution hazard models (HR, 1.264; 95% CI, 1.040–1.536).

Conclusions

Concomitant empiric cefepime improved MRSA BSI clearance and may be useful as the β-lactam component of synergistic vancomycin + β-lactam regimens when empiric or directed gram-negative coverage is desired.
EVALUATION OF RADON CONCENTRATION IN IRRIGATION AND DRINKING WATERS FROM THE EASTERN PART OF OMAN AND ESTIMATION OF EFFECTIVE DOSES TO OMANIS
Authors: Nasser S M , Khandaker M U , Bradley D A , Isinkaye M O
Published: April 2019

The present study concerns measurement of the radon concentration in drinking and irrigation waters obtained from the eastern part of Oman, in particular in regard to water quality assessment of the region. The samples were collected from different places covering most types of water sources in the region. A passive and time-integrated track etch detector (LR-115 type II) combined with a high-resolution optical microscope has been used to obtain the radon concentration in the studied samples. Values of dissolved radon in water varied among the water sources; the highest concentration of radon was found to be 363 Bq m−3 in a drinking water sample while well water used for irrigation showed the lowest value, at 140 Bq m−3. Measured data for all water sources are below the permissible limit of 11.1 kBq m−3 recommended by the US-EPA. Annual effective doses for the studied samples were in the range 0.38–0.99 μSv y−1 which is significantly less than the action level recommended by the WHO (0.1 mSv y−1), indicating that the water sources in the Jalan BBH region of Oman are safe to use. The obtained data may serve as a reference for any future radiological study of the waterbody of this region.
RELATIONSHIP BETWEEN SOIL–SOIL-SOLUTION DISTRIBUTION COEFFICIENTS OF 125I AND 127I IN PASTURE SOIL
Authors: Unno Y , Takeda A , Takaku Y , Hisamatsu S
Published: April 2019

We measured the depth profiles of soil–soil-solution distribution coefficients (Kd) of native 127I (127I-Kd) and exogenous 125I– (125I-Kd) in soils from a pasture near the spent nuclear fuel reprocessing plant in Rokkasho, Japan, and investigated their relationships to depth profiles of the concentration in soil of 127I and organic C and Kd of organic C (C-Kd). The depth profiles of 125I-Kd and 127I-Kd were similar. The relatively low 127I concentrations and low values of both 127I-Kd and 125I-Kd indicate that some of the I deposited on the soil surface have been transported to depths greater than 10 cm. On the other hand, high 127I-Kd/125I-Kd ratios in the uppermost 10 cm of soil indicate that some of the 127I bound to that soil could not be exchanged with exogenous 125I. Although a previous study has shown a power function relationship between 125I-Kd and C-Kd, our data show that the relationships of both 125I-Kd and 127I-Kd to C-Kd are exponential functions. The reason for these conflicting results is unknown. Nonetheless, our data clearly show Kd values for both 125I– and 127I to be dependent on C-Kd. In addition, the dependence of both 127I-Kd and 125I-Kd on C-Kd suggests that organic material in the soil has a role in the transport of I down the soil profile.
Maternal inflammation at midgestation impairs subsequent fetal myoblast function and skeletal muscle growth in rats, resulting in intrauterine growth restriction at term1
Authors: Cadaret Caitlin N , Posont Robert J , Beede Kristin A , Riley Hannah E , Loy John Dustin , Yates Dustin T
Published: April 2019

Maternal inflammation induces intrauterine growth restriction (MI-IUGR) of the fetus, which compromises metabolic health in human offspring and reduces value in livestock. The objective of this study was to determine the effect of maternal inflammation at midgestation on fetal skeletal muscle growth and myoblast profiles at term. Pregnant Sprague-Dawley rats were injected daily with bacterial endotoxin (MI-IUGR) or saline (controls) from the 9th to the 11th day of gestational age (dGA; term = 21 dGA). At necropsy on dGA 20, average fetal mass and upper hindlimb cross-sectional areas were reduced (P < 0.05) in MI-IUGR fetuses compared with controls. MyoD+ and myf5+ myoblasts were less abundant (P < 0.05), and myogenin+ myoblasts were more abundant (P < 0.05) in MI-IUGR hindlimb skeletal muscle compared with controls, indicating precocious myoblast differentiation. Type I and Type II hindlimb muscle fibers were smaller (P < 0.05) in MI-IUGR fetuses than in controls, but fiber type proportions did not differ between experimental groups. Fetal blood plasma TNFα concentrations were below detectable amounts in both experimental groups, but skeletal muscle gene expression for the cytokine receptors TNFR1, IL6R, and FN14 was greater (P < 0.05) in MI-IUGR fetuses than controls, perhaps indicating enhanced sensitivity to these cytokines. Maternal blood glucose concentrations at term did not differ between experimental groups, but MI-IUGR fetal blood contained less (P < 0.05) glucose, cholesterol, and triglycerides. Fetal-to-maternal blood glucose ratios were also reduced (P < 0.05), which is indicative of placental insufficiency. Indicators of protein catabolism, including blood plasma urea nitrogen and creatine kinase, were greater (P < 0.05) in MI-IUGR fetuses than in controls. From these findings, we conclude that maternal inflammation at midgestation causes muscle-centric fetal programming that impairs myoblast function, increases protein catabolism, and reduces skeletal muscle growth near term. Fetal muscle sensitivity to inflammatory cytokines appeared to be enhanced after maternal inflammation, which may represent a mechanistic target for improving these outcomes in MI-IUGR fetuses.
Cryptic habitat use of white sharks in kelp forest revealed by animal-borne video
Authors: Jewell Oliver J. D. , Gleiss Adrian C. , Jorgensen Salvador J. , Andrzejaczek Samantha , Moxley Jerry H. , Beatty Stephen J. , Wikelski Martin , Block Barbara A. , Chapple Taylor K.
Published: April 2019

Traditional forms of marine wildlife research are often restricted to coarse telemetry or surface-based observations, limiting information on fine-scale behaviours such as predator–prey events and interactions with habitat features. We use contemporary animal-attached cameras with motion sensing dataloggers, to reveal novel behaviours by white sharks,
Carcharodon carcharias
, within areas of kelp forest in South Africa. All white sharks tagged in this study spent time adjacent to kelp forests, with several moving throughout densely kelp-covered areas, navigating through channels and pushing directly through stipes and fronds. We found that activity and turning rates significantly increased within kelp forest. Over 28 h of video data revealed that white shark encounters with Cape fur seals,
Arctocephalus pusillus pusillus
, occurred exclusively within kelp forests, with seals displaying predator evasion behaviour during those encounters. Uniquely, we reveal the use of kelp forest habitat by white sharks, previously assumed inaccessible to these large predators.
Sir William Rede Hawthorne. 22 May 1913—16 September 2011
Authors: Greitzer E. M. , Newland D. E.
Published: April 2019

William Rede Hawthorne was a pioneer in gas turbine aerodynamics and thermodynamics, a sought-after technology advisor to industry and government, and a generous and enthusiastic teacher who encouraged students to excel. His outstanding contributions included resolution of combustion problems that limited the operation of the original Whittle jet engine, early in-depth descriptions of compressible channel flow that still inform engineers today, innovative and wide-ranging analyses of secondary flows in turbomachinery that defined the field, and creation of some of the first notes on gas turbine cycle analysis. A theme in the many areas of engineering in which he had impact was the satisfaction from the growth of understanding that can accompany making things work—in his words, ‘machines produce ideas just as surely as ideas produce machines’. A Cambridge graduate, he was a professor at MIT when, in 1951, he was recruited to a newly established chair at Cambridge, where he later had leadership roles as head of the engineering department (1968–73) and Master of Churchill College (1968–83). He retained strong ties to MIT, however, and fostered lasting collaborations between the two universities. Among his numerous awards and honours were the US Medal of Freedom (1947), a Royal Society Medal (1982) and a knighthood (1970) for ‘services to thermodynamics’, a citation that pleased him greatly.
Charles Walter Suckling. 24 July 1920—30 October 2013
Authors: McCann Michael J. , Suckling Colin J.
Published: April 2019

Charles Walter Suckling (1920–2013) is most remembered for being the discoverer of the inhalant anaesthetic halothane, which revolutionized anaesthesia and surgical practice. He was born in Teddington, Middlesex, but grew up largely in Wallasey, Merseyside, where his father was a cargo superintendent for imports from Australia produced by one of Charles’s maternal uncle's cooperatives. Charles was educated at Oldershaw Grammar School, Wallasey, and the University of Liverpool, where he obtained a first class honours degree in chemistry (1942). With this qualification he was directed to carry out national service in the chemical industry at ICI in Widnes and was subsequently able to obtain a scholarship to work towards a PhD at the University of Liverpool (1949), which he was awarded for the structural elucidation of the natural product santal, by classical organic chemical methods. The project leading to the discovery of halothane was begun in 1951 at ICI's Widnes Laboratory and was one of the first examples of rational drug design; halothane reached clinical practice in 1956. This and other industrial research innovations were recognized by his election to the Fellowship of the Royal Society in 1978. Charles’s career at ICI took him into both scientific and commercial management roles, including chairman of Paints Division and general manager of Research and Technology, a company-wide brief at head office, Millbank. After retiring from ICI (1982) he undertook many public service and charitable tasks, including membership of the Royal Commission on Environmental Pollution, for which he was awarded the CBE, and positions on the councils of the Royal College of Anaesthetists and Royal College of Art and Design. Charles retired from professional life fully in 2001. In 1946 he married Eleanor Margaret Watterson; their family comprised twin sons, both of whom became professional scientists, and a daughter, who became a medical doctor. Charles died at Knebworth, Hertfordshire, in 2013.
Reasonable coal pillar design and remote control mining technology for highwall residual coal resources
Authors: Wang Fangtian , Zhang Cun
Published: April 2019

Highwall mining (HWM) technology is an efficient method for exploiting residual coal resources in Chinese open-pit coal mines. However, on-site personnel and equipment can be damaged by the instability of the highwall mining residual coal pillars and subsidence of final end-walls. This paper considers the geological conditions of an open-pit mine in Shendong Coal Field (China) in order to prevent overlying rock fall accidents; the Mark-Bieniawski formula and the FLAC3D numerical simulation are used to analyse reasonable coal pillar widths outside and under the road, which were determined to be 1.7 m and 1.3 m, respectively. Using the EBH132 cantilever excavator for remote control mining, the field experiment shows that the recovery ratio of highwall residual coal resources was over 67%; hence, safety, efficiency and high recovery ratio of highwall mining were achieved for the residual coal resources of an open-pit mine.
An experimental study of the influence of lithology on compaction behaviour of broken waste rock in coal mine backfill
Authors: Li Meng , Zhang Jixiong , Wu Zhongya , Liu Yu , Li Ailing
Published: April 2019

The research aims to explore the influences of lithology on the compaction behaviours of broken waste rocks. For this purpose, a WAW-1000D servo test machine and a self-made bidirectional loading test system for granular materials were used to conduct axial and lateral compaction tests on four typical types of broken waste rocks: sandstone, mudstone, limestone and shale. On this basis, we analysed the relationships between lateral and axial stress with the strain in, and porosity of, the four types of broken waste rocks. In addition, the relationship of axial stress with lateral stress and lateral pressure coefficient, and the changes in the particle size distribution of broken waste rocks before and after compaction were discussed. The test results demonstrated that the samples of higher strength were found to have low lateral and axial strains as well as a lower porosity in axial and lateral loading tests, while samples of lower strength showed low lateral stress and lateral pressure coefficient under axial load. After being compacted, the samples of the four types of broken waste rocks were found to have a higher proportion of small particles, indicating some particle crushing. Moreover, the samples of lower strength were broken to a greater extent.
On fibre dispersion modelling of soft biological tissues: a review
Authors: Holzapfel Gerhard A. , Ogden Ray W. , Sherifova Selda
Published: April 2019

Collagen fibres within fibrous soft biological tissues such as artery walls, cartilage, myocardiums, corneas and heart valves are responsible for their anisotropic mechanical behaviour. It has recently been recognized that the dispersed orientation of these fibres has a significant effect on the mechanical response of the tissues. Modelling of the dispersed structure is important for the prediction of the stress and deformation characteristics in (patho)physiological tissues under various loading conditions. This paper provides a timely and critical review of the continuum modelling of fibre dispersion, specifically, the angular integration and the generalized structure tensor models. The models are used in representative numerical examples to fit sets of experimental data that have been obtained from mechanical tests and fibre structural information from second-harmonic imaging. In particular, patches of healthy and diseased aortic tissues are investigated, and it is shown that the predictions of the models fit very well with the data. It is straightforward to use the models described herein within a finite-element framework, which will enable more realistic (and clinically relevant) boundary-value problems to be solved. This also provides a basis for further developments of material models and points to the need for additional mechanical and microstructural data that can inform further advances in the material modelling.
Spin-flip scattering engendered quantum spin torque in a Josephson junction
Authors: Pal Subhajit , Benjamin Colin
Published: April 2019

We examine a Josephson junction with two ferromagnets and a magnetic impurity sandwiched between two superconductors. In such ferromagnetic Josephson junctions, equilibrium spin torque exists only when ferromagnets are misaligned. This is explained via the ‘conventional’ mechanism of spin transfer torque, which owes its origin to the misalignment of two ferromagnets. However, we see surprisingly when the magnetic moments of the ferromagnets are aligned parallel or anti-parallel, there is a finite equilibrium spin torque due to the quantum mechanism of spin-flip scattering. We explore the properties of this unique spin-flip scattering-induced equilibrium quantum spin torque, especially its tunability via exchange coupling and phase difference across the superconductors.
Why is Amazonia a ‘source’ of biodiversity? Climate-mediated dispersal and synchronous speciation across the Andes in an avian group (Tityrinae)
Authors: Musher Lukas J. , Ferreira Mateus , Auerbach Anya L. , McKay Jessica , Cracraft Joel
Published: April 2019

Amazonia is a ‘source’ of biodiversity for other Neotropical ecosystems, but which conditions triggerin situspeciation and emigration is contentious. Three hypotheses for how communities have assembled include (1) a stochastic model wherein chance dispersal events lead to gradual emigration and species accumulation, (2) diversity-dependence wherein successful dispersal events decline through time due to ecological limits, and (3) barrier displacement wherein environmental change facilitates dispersal to other biomes via transient habitat corridors. We sequenced thousands of molecular markers for the Neotropical Tityrinae (Aves) and applied a novel filtering protocol to identify loci with high utility for dated phylogenomics. We used these loci to estimate divergence times and model Tityrinae's evolutionary history. We detected a prominent role for speciation driven by barriers including synchronous speciation across the Andes and found that dispersal increased toward the present. Because diversification was continuous but dispersal was non-random over time, we show that barrier displacement better explains Tityrinae's history than stochasticity or diversity-dependence. We propose that Amazonia is a source of biodiversity because (1) it is a relic of a biome that was once more extensive, (2) environmentally mediated corridors facilitated emigration and (3) constant diversification is attributed to a spatially heterogeneous landscape that is perpetually dynamic through time.
Winners have higher pre-copulatory mating success but losers have better post-copulatory outcomes
Authors: Filice David C. S. , Dukas Reuven
Published: April 2019

In many animals, the outcomes of competitive interactions can have lasting effects that influence an individual's reproductive success and have important consequences for the strength and direction of evolution via sexual selection. In the fruit fly,Drosophila melanogaster, males that have won previous contests are more likely to win in subsequent conflicts and losers are more likely to lose (winner–loser effects), but the direct fitness consequences and genetic underpinnings of this plasticity are poorly understood. Here, we tested how male genotype and the outcomes of previous male–male conflicts influence male pre- and post-copulatory success. We quantified pre-copulatory success in a choice and no-choice context, and post-copulatory success by quantifying ejaculate offensive and defensive ability. We found that winners have higher reproductive success compared to losers in both pre-copulatory scenarios. However, losers consistently mated for a longer duration, boosted female fecundity and had an increased paternity share when they were the first males to mate, suggesting increased investment into post-copulatory mechanisms. Finally, by using clonal hybrids from theDrosophilaGenetic Reference Panel, we documented that genetic variation explained a sizeable proportion of the observed differences between lines, and of the interaction between line and winner and loser effects. Our results place the behavioural data on winner–loser effects in an evolutionary context by documenting the potential fitness gain to males from altering their reproductive strategy based on fighting experience. Our data may also explain the presence and maintenance of trade-offs between different male reproductive strategies.
Shifts along the parasite–mutualist continuum are opposed by fundamental trade-offs
Authors: Matthews Andrew C. , Mikonranta Lauri , Raymond Ben
Published: April 2019

Theory suggests that symbionts can readily evolve more parasitic or mutualistic strategies with respect to hosts. However, many symbionts have stable interactions with hosts that improve nutrient assimilation or confer protection from pathogens. We explored the potential for evolution of increased parasitism or decreased parasitism and mutualism in a natural gut symbiosis between larvae of
Plutella xylostella
and the microbe
Enterobacter cloacae.
We focused on interactions with the pathogen,
Bacillus thuringiensis
: selecting for parasitism in terms of facilitating pathogen infection, or increased mutualism in terms of host protection. Selection for parasitism led to symbionts increasing pathogen-induced mortality but reduced their competitive ability with pathogens and their
in vitro
growth rates. Symbionts did not evolve to confer protection from pathogens. However, several lineages evolved reduced parasitism, primarily in terms of moderating impacts on host growth, potentially because prudence pays dividends through increased host size. Overall, the evolution of increased parasitism was achievable but was opposed by trade-offs likely to reduce fitness. The evolution of protection may not have occurred because suppressing growth of
B. thuringiensis
in the gut might provide only weak protection or because evolution towards protective interactions was opposed by the loss of competitive fitness in symbionts.
Emergence of a digital cluster in east London: birth of a new hybrid firm
Authors: Evans Graeme Lorenzo
Published: April 2019

Purpose

This paper aims to investigate the composition and geography of an emerging “creative digital” cluster in London, in the context of cluster theory and emerging creative cluster concepts. This argues that this cluster cannot be divorced from the wider regional creative and digital economy and that its inter-dependence with a small number of “content” industries is critical to its formation. The significance of the “creative digital” firm blending design, communications and technological development is highlighted, as is its unique position in enabling such firms to flourish.

Design/methodology/approach

The research combines both quantitative with qualitative methods, based on cluster analysis of firm-level business data using GIS mapping software at a regional level; location quotient (LQ) analysis to reveal firm concentration at a local cluster level; an online questionnaire survey of firms within this cluster; participant observation of firm meet-ups over a three-year period; and face-to-face interviews with a sample of firms/owners.

Findings

The evidence generated from this research confirms the distinctive nature of this digital cluster and the benefits of co-location in an industrial district with proximities to a range of advanced producer services and cultural content provision. This has revealed an emerging “techno-creative habitus” (Scott 2010), which has been able to take advantage of market fluidity through a network of communities of interest firms, which have reshaped an existing global hub locally anchored by a highly porous locale.

Originality/value

The research is novel in combining spatial data analysis with qualitative research into firm behaviour and place-based factors that support the growth of this cluster. This has revealed new insights into the hybrid nature of tech firms that integrate content with both hardware and software applications and who innovate and grow through inter-personal cluster networks. This contributes to cluster theory and extends the range of proximities – social, institutional and cultural – that enhance the geographic advantages of clustering in this case.