bluuebunny/crossref_metadata_2025 huggingface dataset:
The influence of non-idealities on the thermoelectric power factor of nanostructured superlattices
Authors: Thesberg Mischa , Pourfath Mahdi , Kosina Hans , Neophytou Neophytos
Published: December 2015

Cross-plane superlattices composed of nanoscale layers of alternating potential wells and barriers have attracted great attention for their potential to provide thermoelectric power factor improvements and higher ZT figure of merit. Previous theoretical works have shown that the presence of optimized potential barriers could provide improvements to the Seebeck coefficient through carrier energy filtering, which improves the power factor by up to 40%. However, experimental corroboration of this prediction has been extremely scant. In this work, we employ quantum mechanical electronic transport simulations to outline the detrimental effects of random variation, imperfections, and non-optimal barrier shapes in a superlattice geometry on these predicted power factor improvements. Thus, we aim to assess either the robustness or the fragility of these theoretical gains in the face of the types of variation one would find in real material systems. We show that these power factor improvements are relatively robust against: overly thick barriers, diffusion of barriers into the body of the wells, and random fluctuations in barrier spacing and width. However, notably, we discover that extremely thin barriers and random fluctuation in barrier heights by as little as 10% is sufficient to entirely destroy any power factor benefits of the optimized geometry. Our results could provide performance optimization routes for nanostructured thermoelectrics and elucidate the reasons why significant power factor improvements are not commonly realized in superlattices, despite theoretical predictions.
Temperature-dependent elastic properties of Ti1−xAlxN alloys
Authors: Shulumba Nina , Hellman Olle , Rogström Lina , Raza Zamaan , Tasnádi Ferenc , Abrikosov Igor A. , Odén Magnus
Published: December 2015

Ti1−xAlxN is a technologically important alloy that undergoes a process of high temperature age-hardening that is strongly influenced by its elastic properties. We have performed first principles calculations of the elastic constants and anisotropy using the symmetry imposed force constant temperature dependent effective potential method, which include lattice vibrations and therefore the effects of temperature, including thermal expansion and intrinsic anharmonicity. These are compared with in situ high temperature x-ray diffraction measurements of the lattice parameter. We show that anharmonic effects are crucial to the recovery of finite temperature elasticity. The effects of thermal expansion and intrinsic anharmonicity on the elastic constants are of the same order, and cannot be considered separately. Furthermore, the effect of thermal expansion on elastic constants is such that the volume change induced by zero point motion has a significant effect. For TiAlN, the elastic constants soften non-uniformly with temperature: C11 decreases substantially when the temperature increases for all compositions, resulting in an increased anisotropy. These findings suggest that an increased Al content and annealing at higher temperatures will result in a harder alloy.
Coherent diffractive imaging using randomly coded masks
Authors: Seaberg Matthew H. , d'Aspremont Alexandre , Turner Joshua J.
Published: December 2015

We experimentally demonstrate an extension to coherent diffractive imaging that encodes additional information through the use of a series of randomly coded masks, removing the need for typical object-domain constraints while guaranteeing a unique solution to the phase retrieval problem. Phase retrieval is performed using a numerical convex relaxation routine known as “PhaseCut,” an iterative algorithm known for its stability and for its ability to find the global solution, which can be found efficiently and which is robust to noise. The experiment is performed using a laser diode at 532.2 nm, enabling rapid prototyping for future X-ray synchrotron and even free electron laser experiments.
Understanding the doping effects on the structural and electrical properties of ultrathin carbon nanotube networks
Authors: Zhou Ying , Shimada Satoru , Saito Takeshi , Azumi Reiko
Published: December 2015

Similar to other semiconductor technology, doping of carbon nanotube (CNT) thin film is of great significance for performance improvement or modification. However, it still remains a challenge to seek a stable and effective dopant. In this paper, we unitize several spectroscopic techniques and electrical characterizations under various conditions to investigate the effects of typical dopants and related methods. Nitric acid (HNO3) solution, I2 vapor, and CuI nanoparticles are used to modify a series of ultrathin CNT networks. Although efficient charge transfer is achieved initially after doping, HNO3 is not applicable because it suffers from severe reliability problems in structural and electrical properties, and it also causes a number of undesired structural defects. I2 vapor doping at 150 °C can form some stable C-I bonding structures, resulting in relatively more stable but less efficient electrical performances. CuI nanoparticles seem to be an ideal dopant. Photonic curing enables the manipulation of CuI, which not only results in the construction of novel CNT-CuI hybrid structures but also encourages the deepest level of charge transfer doping. The excellent reliability as well as processing feasibility identify the bright perspective of CNT-CuI hybrid film for practical applications.
Mass correlation spectroscopy for mass- and size-based nanoparticle characterization in fluid
Authors: Modena Mario M. , Burg Thomas P.
Published: December 2015

The characterization of nanoparticles is an important problem in many areas of applied physics, chemistry, medicine, and biology. Micromechanical resonators with embedded fluidic channels represent a powerful new technology for particle characterization through direct measurement of the buoyant mass of nanoparticles in solution with attogram resolution (1 ag = 10−18 g). We recently showed that correlation analysis greatly expands the range of applications by enabling measurements of mass even when the individual particles are far lighter than the conventional detection limit. Here, we extend the concept of mass correlation spectroscopy further to simultaneously measure the ensemble-averaged size and mass of nanoparticles by exploiting size-dependent differences in hydrodynamic dispersion. To do so, we first derive an approximate model of the dispersion of finite-size particles flowing through a microfluidic channel of rectangular cross-section, valid in a large range of dispersion regimes. By including this solution into the model describing the correlation function of the time-domain mass signal acquired with a micromechanical resonator, information on particle size can be obtained during mass characterization without requiring any modification of the devices. The validity of the analysis is corroborated both by numerical simulations and experimental measurements on nanoparticles of different materials ranging from 15 nm to 500 nm.
Oxygen assisted interconnection of silver nanoparticles with femtosecond laser radiation
Authors: Huang H. , Duley W. W. , Zhou Y.
Published: December 2015

Ablation of silver (Ag) nanoparticles in the direction of laser polarization is achieved by utilizing femtosecond laser irradiation in air at laser fluence ranging from ∼2 mJ/cm2 to ∼14 mJ/cm2. This directional ablation is attributed to localized surface plasmon induced localized electric field enhancement. Scanning electron microscopy observations of the irradiated particles in different gases and at different pressures indicate that the ablation is further enhanced by oxygen in the air. This may be due to the external heating via the reactions of its dissociation product, atomic oxygen, with the surface of Ag particles, while the ablated Ag is not oxidized. Further experimental observations show that the ablated material re-deposits near the irradiated particles and results in the extension of the particles in laser polarization direction, facilitating the interconnection of two well-separated nanoparticles.
Excited-state intramolecular proton transfer of 2-acetylindan-1,3-dione studied by ultrafast absorption and fluorescence spectroscopy
Authors: Verma Pramod Kumar , Steinbacher Andreas , Schmiedel Alexander , Nuernberger Patrick , Brixner Tobias
Published: December 2015

We employ transient absorption from the deep-UV to the visible region and fluorescence upconversion to investigate the photoinduced excited-state intramolecular proton-transfer dynamics in a biologically relevant drug molecule, 2-acetylindan-1,3-dione. The molecule is a ß-diketone which in the electronic ground state exists as exocyclic enol with an intramolecular H-bond. Upon electronic excitation at 300 nm, the first excited state of the exocyclic enol is initially populated, followed by ultrafast proton transfer (≈160 fs) to form the vibrationally hot endocyclic enol. Subsequently, solvent-induced vibrational relaxation takes place (≈10 ps) followed by decay (≈390 ps) to the corresponding ground state.
Polaronic conduction and Anderson localization in reduced strontium barium niobate
Authors: Dandeneau Christopher S. , Yang YiHsun , Olmstead Marjorie A. , Bordia Rajendra K. , Ohuchi Fumio S.
Published: December 2015

Electron transport mechanisms in reduced Sr0.5Ba0.5Nb2O6 (SBN50) are investigated from ∼100 to 955 K through an analysis of the electrical conductivity (σ) and the Seebeck coefficient (S) with respect to temperature (T). Notably, experimental evidence is presented that supports a scenario of Anderson localization below 600 K and carrier excitation across a mobility edge at higher temperature. As a relaxor ferroelectric, stoichiometric SBN has intrinsic disorder associated with both the distribution of Sr/Ba vacancies and the formation of polarized nanoregions. The removal of oxygen through reduction generates conduction electrons in SBN. At the lowest temperatures measured (100–155 K), the electrical conductivity exhibits a temperature dependence characteristic of variable range hopping, followed by a transition to small polaron hopping at intermediate temperatures (250–545 K). In both the variable range and small polaron hopping regimes, a semiconductor-like temperature dependence of the electrical conductivity (dσ/dT > 0) was observed. However, above 615 K, dσ/dT decreases dramatically and eventually becomes metal-like (dσ/dT < 0). Concomitantly, the Seebeck coefficient exhibits a linear dependence on lnT from 615 to 955 K with the same slope (∼104 μ V/K) for both polycrystalline SBN50 and single crystalline SBN61 (both reduced), indicating a similar, constant density of states near the Fermi level for both compositions. The application of Seebeck coefficient theory to this inherently disordered material reveals that the excitation of carriers across a mobility edge is likely responsible for the change in dσ/dT at high temperature. Such findings may have a significant impact in the field of conductive ferroelectrics.
Suppression of surface charge accumulation on Al2O3-filled epoxy resin insulator under dc voltage by direct fluorination
Authors: Zhang Boya , Zhang Guixin , Wang Qiang , Li Chuanyang , He Jinliang , An Zhenlian
Published: December 2015

Surface charge accumulation on insulators under high dc voltage is a major factor that may lead to the reduction of insulation levels in gas insulated devices. In this paper, disc insulators made of Al2O3-filled epoxy resin were surface fluorinated using a F2/N2 mixture (12.5% F2) at 50 °C and 0.1 MPa for different durations of 15 min, 30 min and 60 min. A dc voltage was applied to the insulator for 30 min and the charge density on its surface was measured by an electrostatic probe. The results revealed significant lower surface charge densities on the fluorinated insulators in comparison with the original one. Surface conductivity measurements indicated a higher surface conductivity by over three orders of magnitude after fluorination, which would allow the charges to transfer along the surface and thus may suppress their accumulation. Further, attenuated total reflection infrared analysis and surface morphology observations of the samples revealed that the introduction of fluoride groups altered the surface physicochemical properties. These structure changes, especially the physical defects reduced the depth of charge traps in the surface layer, which was verified by the measurement of energy distributions of the electron and hole traps based on the isothermal current theory. The results in this paper demonstrate that fluorination can be a promising and effective method to suppress surface charge accumulation on epoxy insulators in gas insulated devices.
The contact area dependent interfacial thermal conductance
Authors: Liu Chenhan , Wei Zhiyong , Wang Jian , Bi Kedong , Yang Juekuan , Chen Yunfei
Published: December 2015

The effects of the contact area on the interfacial thermal conductance σ are investigated using the atomic Green’s function method. Different from the prediction of the heat diffusion transport model, we obtain an interesting result that the interfacial thermal conductance per unit area Λ is positively dependent on the contact area as the area varies from a few atoms to several square nanometers. Through calculating the phonon transmission function, it is uncovered that the phonon transmission per unit area increases with the increased contact area. This is attributed to that each atom has more neighboring atoms in the counterpart of the interface with the increased contact area, which provides more channels for phonon transport.
171 NORMAL VERSUS LOW ANTI-MULLERIAN HORMONE IN PATIENTS WITH ADVANCED MATERNAL AGE: IN VITRO FERTILIZATION OUTCOMES AND MORPHOKINETIC PARAMETERS
Authors: Kotlyar A. , Flyckt R. , Desai N.
Published: December 2015

Anti-Mullerian hormone (AMH) levels are often used in an IVF population for assessment of ovarian reserve. However, it is not well understood whether AMH levels predict implantation and clinical pregnancy in older women undergoing IVF. In this study, we sought to compare IVF outcomes and morphokinetic parameters in patients 38 years and older with normal versus low AMH levels. Experimental design was a single-centre, retrospective cohort study. Time-lapse imaging data were evaluated for patients 38 years and older (n = 81). Patients were divided into those with AMH values less than 1.0 (n = 47) versus greater than or equal to 1.0 (n = 34). Morphokinetic data was then analysed from transferred blastocysts from these patients cultured in the Embryoscope until transfer (n = 100). The morphokinetic parameters examined were time to 2 cell (t2), 4 cell(t4), 5 cell (t5), time to synchronous divisions (s2, s3), duration of the second cell cycle (cc2), and third cell cycle (cc3). Implantation and clinical pregnancy were identified based upon the presence of a gestational sac. Fertilization, implantation, clinical pregnancy, and blastocyst formation rates were compared between normal and low AMH groups (Table 1). Mean morphokinetic parameters were compared between the 2 AMH groups using an unpaired t-test. Chi-squared tests were used for proportions. P < 0.05 was considered statistically significant. Results: Age of the patients ranged from 38–43, (41.3 ± 2.2 years). The results are summarised below. There were significant differences between implantation and clinical pregnancy rates for low and normal AMH levels. Morphokinetic parameters among the transferred embryos did not differ significantly between the 2 AMH groups (NS, data not shown). Conclusions: This initial data indicates that, in an IVF population 38 years and older, AMH levels greater than or equal to the cutoff of 1 ng mL–1 are associated not only with increased oocyte retrieval, but also with increased implantation rates and clinical pregnancy rates. These differences suggest that AMH may have a predictive role in determining the likelihood of clinical pregnancy in the 38 years and older patient population.

Table 1.Oocyte harvest and IVF outcomes
37 DOUBLE FREEZING AND THAWING OF NGUNI BULL SEMEN
Authors: Mphaphathi M. L. , Seshoka M. M. , Netshirovha T. R. , Raphalalani Z. C. , Chokoe T. C. , Nkadimeng M. , Kanuya N. L. , Greyling J. P. C. , Nedambale T. L.
Published: December 2015

Indigenous bulls semen are important for conservation programs. The objectives of this study were to evaluate the effects of repeated freezing and thawing on sperm motility characteristics. Semen was collected from 4 Nguni bulls by means of electro ejaculator and stored in a thermo flask (37°C). Sperm total motility, progressive and nonprogressive motility, and velocity were assessed using computer-aided sperm analysis before and after freezing. Semen was then diluted with egg yolk citrate extender (fraction A), then followed by 12% of glycerol + egg yolk citrate extender (fraction B, Seshoka et al. 2012). Diluted semen samples were equilibrated for 4 h at 5°C. After the equilibration period, samples were loaded into 0.25-mL straws and transferred into a controlled rate programmable freezer. After the target temperature of –130°C was reached, semen straws were stored in a LN tank (–196°C). After 3 months of storage, straws were thawed at 15°C (first and second freezing and thawing followed the same process) for 5 min and further evaluated post-thawed at 0 and 15 min during incubation at 15°C. Treatment means were separated using Fisher’s protected t-test least. No significant differences were recorded between the raw semen total sperm motility percentage (93.2%) and first frozen-thawed at 0 min (82.6%), with the total sperm motility rate recovery of 88.6%. In addition, there was a marked decline recorded in sperm total motility during the first frozen-thawed at 15 min (77.6%), second frozen-thawed at 0 min (31.3%), and second frozen-thawed at 15 min (30.1%; P < 0.05). The sperm curvilinear velocity and average path velocity was reduced following first frozen-thawed (P < 0.05) but remained constant and stable between the treatment groups (P > 0.05). In conclusion, the freezing-thawing process did not reduce the Nguni bull total sperm motility during the first freezing and thawing process, compared with raw semen. However, a drastic decline was recorded during the second freezing-thawing processes, compared with raw semen.
Signatures and control of strong-field dynamics in a complex system
Authors: Meyer Kristina , Liu Zuoye , Müller Niklas , Mewes Jan-Michael , Dreuw Andreas , Buckup Tiago , Motzkus Marcus , Pfeifer Thomas
Published: December 2015

Significance

Using intense lasers to control complex molecules is a long-held dream in science. In this article, we develop a physics concept for measuring and controlling the quantum states of complex molecules by strong laser fields. We show that, in particular, the quantum-mechanical phase of excited molecular states can be manipulated by the intense laser, a key quantity for full (amplitude and phase) control of molecular quantum states. With the help of time- and intensity-resolved absorption spectroscopy experiments, we apply this idea to the dynamics of a large dye molecule in solution. The demonstrated phase-control concept thus represents a major leap toward the ultimate goal of laser chemistry.
Fasting protects mice from lethal DNA damage by promoting small intestinal epithelial stem cell survival
Authors: Tinkum Kelsey L. , Stemler Kristina M. , White Lynn S. , Loza Andrew J. , Jeter-Jones Sabrina , Michalski Basia M. , Kuzmicki Catherine , Pless Robert , Stappenbeck Thaddeus S. , Piwnica-Worms David , Piwnica-Worms Helen
Published: December 2015

Significance

Cancer patients undergoing chemotherapy experience high rates of dose-limiting morbidity. Recently, short-term fasting prior to chemotherapy was shown to decrease toxicity. Herein we report that fasting protects multiple small intestinal stem cell populations marked by
Lgr5
,
Bmi1
, or
HopX
expression and maintains barrier function to preserve small intestinal architecture from lethal DNA damage. Our findings provide insight into how fasting protects the host from toxicity associated with high-dose chemotherapy.
Eleventh-century shift in timber procurement areas for the great houses of Chaco Canyon
Authors: Guiterman Christopher H. , Swetnam Thomas W. , Dean Jeffrey S.
Published: December 2015

Significance

The iconic great houses of Chaco Canyon occupy a nearly treeless landscape and yet were some of the largest pre-Columbian structures in North America. This incongruity has sparked persistent debate over the origins of more than 240,000 trees used in construction. We used tree-ring methods for determining timber origins for the first time to our knowledge in the southwestern United States and show that 70% of timbers likely originated over 75 km from Chaco. We found that a previously unrecognized timber source, the Zuni Mountains, supplied construction beams as early as the 850s in the Common Era. Further, we elucidate shifting dynamics of procurement that highlight the importance of a single landscape, the Chuska Mountains, in the florescence of the Chacoan system.
Omega-3 deficiency impairs honey bee learning
Authors: Arien Yael , Dag Arnon , Zarchin Shlomi , Masci Tania , Shafir Sharoni
Published: December 2015

Significance

Omega-3 is an essential polyunsaturated fatty acid (PUFA) that most animals need to acquire in their diet. Mammalian brains are rich in docosahexaenoic acid (DHA), a long-chain form of omega-3, whose deficiency, coupled with a high omega-6:3 ratio, leads to numerous cognitive disorders and mental diseases. Insects have only trace amounts of long-chain PUFAs, and the effect of omega-3 deficiency on cognition has not been studied. We found that omega-3 deficiency greatly impaired honey bee learning, extending the finding of the importance of omega-3 to a nonmammal, despite lack of DHA in its brain. Furthermore, our analyses of pollens suggest that many managed colonies are experiencing a shift in available forage toward a higher omega-6:3 ratio, which may be leading to colony declines.
Constant mortality and fertility over age inHydra
Authors: Schaible Ralf , Scheuerlein Alexander , Dańko Maciej J. , Gampe Jutta , Martínez Daniel E. , Vaupel James W.
Published: December 2015

Significance

How an organism changes with age and why the pattern of change differs across species are questions that have intrigued biologists since Aristotle. Patterns of change can be described by trajectories of birth and death rates over age. For humans and many other mammals, mortality increases and fertility declines with age among adults. For other species, however, a remarkable variety of patterns has been observed. Although roughly constant mortality and fertility trajectories have been reported for some species, the data are problematic because sample sizes are small, especially at older ages. Here, we present compelling evidence for constant mortality and reproduction ofHydrausing data from careful, large-scale studies over 8 y with 2,256 individuals.
Coordinated regulation of vegetative and reproductive branching in rice
Authors: Wang Lei , Sun Shengyuan , Jin Jiye , Fu Debao , Yang Xuefei , Weng Xiaoyu , Xu Caiguo , Li Xianghua , Xiao Jinghua , Zhang Qifa
Published: December 2015

Significance

The patterns of lateral branching, including tillers and inflorescence branches, determine grain yields of many cereals. In this study, we characterized a regulatory network composed of microRNAs and transcription factor that coordinately regulate vegetative (tiller) and reproductive (panicle) branching in rice. The findings hold tremendous promise for application in rice genetic improvement and may also have general implications for understanding branching regulation of grasses.
Using Social Innovation as a Theoretical Framework to Guide Future Thinking on Facilitating Collaboration Between Mental Health and Criminal Justice Services
Authors: Hean Sarah , Willumsen Elisabeth , Ødegård Atle , Bjørkly Stål
Published: December 2015

Offender mental health is a major societal challenge. Improved collaboration between mental health and criminal justice services is required to address this challenge. This article explores social innovation as a conceptual framework with which to view these collaborations and develop theoretically informed strategies to optimize interorganizational working. Two key innovation frameworks are applied to the offender mental health field and practice illustrations provided of where new innovations in collaboration, and specifically co-creation between the mental health system and criminal justice system, take place. The article recommends the development of a competency framework for leaders and front line staff in the mental health system and criminal justice systems to raise awareness and skills in the innovation process, especially through co-creation across organizational boundaries.
Entropy degeneration of convex projective surfaces
Authors: Nie Xin
Published: December 2015

We show that the volume entropy of the Hilbert metric on a closed convex projective surface tends to zero as the corresponding Pick differential tends to infinity. The proof is based on the fact, due to Benoist and Hulin, that the Hilbert metric and the Blaschke metric are comparable.
Extending gene ontology with gene association networks
Authors: Peng Jiajie , Wang Tao , Wang Jixuan , Wang Yadong , Chen Jin
Published: December 2015

Motivation: Gene ontology (GO) is a widely used resource to describe the attributes for gene products. However, automatic GO maintenance remains to be difficult because of the complex logical reasoning and the need of biological knowledge that are not explicitly represented in the GO. The existing studies either construct whole GO based on network data or only infer the relations between existing GO terms. None is purposed to add new terms automatically to the existing GO.

Results: We proposed a new algorithm ‘GOExtender’ to efficiently identify all the connected gene pairs labeled by the same parent GO terms. GOExtender is used to predict new GO terms with biological network data, and connect them to the existing GO. Evaluation tests on biological process and cellular component categories of different GO releases showed that GOExtender can extend new GO terms automatically based on the biological network. Furthermore, we applied GOExtender to the recent release of GO and discovered new GO terms with strong support from literature.

Availability and implementation: Software and supplementary document are available at www.msu.edu/%7Ejinchen/GOExtender

Contact:  jinchen@msu.edu or ydwang@hit.edu.cn

Supplementary information:  Supplementary data are available at Bioinformatics online.
Program extraction applied to monadic parsing
Authors: Berger Ulrich , Jones Alison , Seisenberger Monika
Published: December 2015

This article outlines a proof-theoretic approach to developing correct and terminating monadic parsers. Using modified realizability, we extract formally verified and terminating programs from formal proofs. By extracting both primitive parsers and parser combinators, it is ensured that all complex parsers built from these are also correct, complete and terminating for any input. We demonstrate the viability of our approach by means of two case studies: we extract (i) a small arithmetic calculator and (ii) a non-deterministic natural language parser. The work is being carried out in the interactive proof system Minlog.
Varietal Response to Groundnut Rosette Disease and the First Report of Groundnut ringspot virus in Ghana
Authors: Appiah Andrew S. , Offei Samuel K. , Tegg Robert S. , Wilson Calum R.
Published: December 2015

Twelve cultivars of groundnut were screened in field trials for resistance to groundnut rosette disease (GRD), caused by coinfection with Groundnut rosette assistor virus (GRAV), Groundnut rosette virus (GRV), and its satellite RNA in the coastal savannah of Ghana. ‘Oboshie’ groundnut was rated as highly resistant; ‘Bremaowuo’, ‘Nkatefufuo’, and ‘Behenase’ as resistant; and ‘Nkosuor’, ‘Kumawu’, and ‘Otuhia’ as moderately resistant. GRAV infection rates of 11.8 to 61.8% (dry season) and 13.9 to 100% (wet season) were found, which included symptomless plants, suggesting that some lacked coinfection with GRV and its satellite. Chlorotic ringspot and line-pattern symptoms were observed, suggesting infection with Groundnut ringspot virus (GRSV). Virus identity was confirmed by enzyme-linked immunosorbent assay, reverse-transcription polymerase chain reaction, and amplicon sequencing. This is the first report of GRSV in Ghana. GRSV infection rates were 0.0 to 69.5% (dry season) and 26.1 to 69.5% (wet season). Mixed infections of GRAV and GRSV were common in all cultivars except Nkosuor and Bremaowuo in the dry season. Most cultivars graft inoculated with GRD showed significantly reduced height, leaf area, chlorophyll content, dry haulm weight, and seed yield compared with healthy plants. The sources of resistance to GRD and possibly GRAV and GRSV identified in this study could be exploited in groundnut breeding programs.
Insulin Signaling in Bupivacaine-induced Cardiac Toxicity
Authors: Fettiplace Michael R. , Kowal Katarzyna , Ripper Richard , Young Alexandria , Lis Kinga , Rubinstein Israel , Bonini Marcelo , Minshall Richard , Weinberg Guy
Published: December 2015

AbstractAbstract

In vivo, local anesthetic toxicity altered phosphorylation at targets of glucose metabolism, including Akt, 5′-adenosine monophosphate–activated protein kinase and insulin receptor substrate-1. IV lipid emulsion reduced these local anesthetic–induced changes in phosphorylation.

Background

The impact of local anesthetics on the regulation of glucose homeostasis by protein kinase B (Akt) and 5′-adenosine monophosphate–activated protein kinase (AMPK) is unclear but important because of the implications for both local anesthetic toxicity and its reversal by IV lipid emulsion (ILE).

Methods

Sprague–Dawley rats received 10 mg/kg bupivacaine over 20 s followed by nothing or 10 ml/kg ILE (or ILE without bupivacaine). At key time points, heart and kidney were excised. Glycogen content and phosphorylation levels of Akt, p70 s6 kinase, s6, insulin receptor substrate-1, glycogen synthase kinase-3β, AMPK, acetyl-CoA carboxylase, and tuberous sclerosis 2 were quantified. Three animals received Wortmannin to irreversibly inhibit phosphoinositide-3-kinase (Pi3k) signaling. Isolated heart studies were conducted with bupivacaine and LY294002—a reversible Pi3K inhibitor.

Results

Bupivacaine cardiotoxicity rapidly dephosphorylated Akt at S473 to 63 ± 5% of baseline and phosphorylated AMPK to 151 ± 19%. AMPK activation inhibited targets downstream of mammalian target of rapamycin complex 1 via tuberous sclerosis 2. Feedback dephosphorylation of IRS1 to 31 ± 8% of baseline sensitized Akt signaling in hearts resulting in hyperphosphorylation of Akt at T308 and glycogen synthase kinase-3β to 390 ± 64% and 293 ± 50% of baseline, respectively. Glycogen accumulated to 142 ± 7% of baseline. Irreversible inhibition of Pi3k upstream of Akt exacerbated bupivacaine cardiotoxicity, whereas pretreating with a reversible inhibitor delayed the onset of toxicity. ILE rapidly phosphorylated Akt at S473 and T308 to 150 ± 23% and 167 ± 10% of baseline, respectively, but did not interfere with AMPK or targets of mammalian target of rapamycin complex 1.

Conclusion

Glucose handling by Akt and AMPK is integral to recovery from bupivacaine cardiotoxicity and modulation of these pathways by ILE contributes to lipid resuscitation.
Prophylactic Intramedullary Rodding Following Femoral Lengthening in Congenital Deficiency of the Femur
Authors: Abdelgawad Amr A. , Jauregui Julio J. , Standard Shawn C. , Paley Dror , Herzenberg John E.
Published: December 2015

Introduction:

Femoral fracture after lengthening of congenital femoral deficiency (CFD) is a common complication with a high incidence, up to 50%. The purpose of this study is to determine whether prophylactic intramedullary Rush rodding after lengthening for CFD is an effective method to prevent femoral fracture and to assess any complications that may result.

Methods:

Forty-five femoral lengthenings (43 CFD patients) were performed using external fixation. At the time of frame removal (except for 3 cases, 8 d later), prophylactic intramedullary Rush rods were inserted. Special reaming techniques were developed to pass a Rush rod through the solid regenerate bone and past sclerotic pin sites. Mean age at time of rodding was 6.9 years (range, 2.9 to 14.2 y). Mean duration of treatment with external fixation was 184 days (range, 146 to 461 d). Mean follow-up was 4.2 years (range, 1.3 to 8.2 y). This group of cases was compared with a historical cohort of 95 femoral lengthening procedures for CFD without prophylactic intramedullary rodding after frame removal previously performed at the same institute by the same surgeons.

Results:

Eight cases (18%) developed fracture despite intramedullary rodding (1 case with relatively high-energy trauma, 3 cases during physical therapy, and 4 cases spontaneously). Only 4 of these fractures required intervention. Fractures were more common when a 3.18 mm Rush rod was used (28%) compared with 4.76 mm (8.3%). Patients with prophylactic rodding had a significantly lower incidence of femur fracture rodding than those who did not (18% vs. 34%, respectively; P=0.04). Three out of 45 Rush rods (7%) developed infection that were treated by debridement and removal of the rod, and all healed uneventfully without residual or recurrent infection. There were no cases of avascular necrosis.

Conclusions:

Prophylactic intramedullary rodding is a safe and effective method to prevent femoral fractures after CFD lengthening. Use of 4.76 mm rod is preferred. The risk of infection is acceptable, when compared with the risk of fracture, loss of length, and angulation.

Level of Evidence:

Level III—a retrospective comparative study.
Modulation by the Noble Gas Helium of Tissue Plasminogen Activator: Effects in a Rat Model of Thromboembolic Stroke*
Authors: Haelewyn Benoit , David Hélène N. , Blatteau Jean-Eric , Vallée Nicolas , Meckler Cedric , Risso Jean-Jacques , Abraini Jacques H.
Published: December 2015

Interventions:

Helium has been shown to provide neuroprotection in mechanical model of acute ischemic stroke by inducing hypothermia, a condition shown by itself to reduce the thrombolytic and proteolytic properties of tissue plasminogen activator. However, whether or not helium interacts with the thrombolytic drug tissue plasminogen activator, the only approved therapy of acute ischemic stroke still remains unknown. This point is not trivial since previous data have shown the critical importance of the time at which the neuroprotective noble gases xenon and argon should be administered, during or after ischemia, in order not to block tissue plasminogen activator–induced thrombolysis and to obtain neuroprotection and inhibition of tissue plasminogen activator–induced brain hemorrhages.

Measurements and Main Results:

We show that helium of 25–75 vol% inhibits in a concentration-dependent fashion the catalytic and thrombolytic activity of tissue plasminogen activator in vitro and ex vivo. In vivo, in rats subjected to thromboembolic brain ischemia, we found that intraischemic helium at 75 vol% inhibits tissue plasminogen activator–induced thrombolysis and subsequent reduction of ischemic brain damage and that postischemic helium at 75 vol% reduces ischemic brain damage and brain hemorrhages.

Conclusions:

In a clinical perspective for the treatment of acute ischemic stroke, these data suggest that helium 1) should not be administered before or together with tissue plasminogen activator therapy due to the risk of inhibiting the benefit of tissue plasminogen activator–induced thrombolysis; and 2) could be an efficient neuroprotective agent if given after tissue plasminogen activator–induced reperfusion.
Accuracy of 99mTechnetium-labeled RBC Scintigraphy and MDCT With Gastrointestinal Bleed Protocol for Detection and Localization of Source of Acute Lower Gastrointestinal Bleeding
Authors: Awais Muhammad , Haq Tanveer Ul , Rehman Abdul , Zaman Maseeh Uz , Haider Zishan , Khattak Yasir Jamil , Baloch Noor Ul-Ain
Published: December 2015

Background:

Acute lower gastrointestinal bleeding (LGIB) is a major cause of morbidity and mortality. Multidetector row computed tomography (CT) with gastrointestinal (GI) bleed protocol is a novel diagnostic technique for detecting and localizing LGIB. Being rapid and noninvasive, it may be useful as a first-line modality to investigate cases of acute LGIB.

Goals:

To assess and compare diagnostic accuracy of 99mTechnetium (Tc)-labeled red blood cell (RBC) scintigraphy and multidetector row CT with GI bleed protocol for detection and localization of source of acute LGIB.

Study:

Requirement of informed consent was waived for this retrospective study. Seventy-six patients had undergone either RBC scintigraphy, CT with GI bleed protocol, or both, followed by conventional angiography for evaluation of acute persistent LGIB between January 2010 and February 2014 at our institution. Accuracy of both modalities was assessed using conventional angiography as reference standard and compared using the 2-tailed, Fisher exact test. A P-value of <0.05 was considered statistically significant.

Results:

Fifty-one, 20, and 5 patients had undergone RBC scintigraphy only, CT with GI bleed protocol only, and both modalities, respectively. Fourteen of 25 patients in the CT group had angiographic evidence of active bleeding as compared with 32 of 56 patients in the scintigraphy group. CT with GI bleed protocol had higher accuracy (96%) than 99mTc-labeled RBC scintigraphy (55.4%, P<0.001).

Conclusions:

CT with GI bleed protocol was more accurate in detecting and localizing the source of acute LGIB as compared with 99mTc-labeled RBC scintigraphy.
Change Blindness in 3D Virtual Reality
Authors: Vasser Madis , Kängsepp Markus , Aru Jaan
Published: December 2015

In the present change blindness study subjects explored stereoscopic three dimensional (3D) environments through a virtual reality (VR) headset. A novel method that tracked the subjects’ head movements was used for inducing changes in the scene whenever the changing object was out of the field of view. The effect of change location (foreground or background in 3D depth) on change blindness was investigated. Two experiments were conducted, one in the lab (n = 50) and the other online (n = 25). Up to 25% of the changes were undetected and the mean overall search time was 27 seconds in the lab study. Results indicated significantly lower change detection success and more change cycles if the changes occurred in the background, with no differences in overall search times. The results confirm findings from previous studies and extend them to 3D environments. The study also demonstrates the feasibility of online VR experiments.
Dynamics of microbial community composition and soil organic carbon mineralization in soil following addition of pyrogenic and fresh organic matter
Authors: Whitman Thea , Pepe-Ranney Charles , Enders Akio , Koechli Chantal , Campbell Ashley , Buckley Daniel H. , Lehmann Johannes
Published: December 2015

Pyrogenic organic matter (PyOM) additions to soils can have large impacts on soil organic C (SOC) cycling. Because the soil microbial community drives SOC fluxes, understanding how PyOM additions affect soil microbes is essential to understanding how PyOM affects SOC. We studied SOC dynamics and surveyed soil microbial communities after OM additions in a field experiment. We produced and applied either 350°C corn stover PyOM or an equivalent amount of dried corn stover to a Typic Fragiudept soil. Stover increased SOC-derived and total CO2fluxes (up to 6x), and caused rapid and persistent changes in bacterial community composition over 82 days. In contrast, PyOM only temporarily increased total soil CO2fluxes (up to 2x) and caused fewer changes in bacterial community composition. 70% of the OTUs that increased in response to PyOM additions also responded to stover additions. These OTUs likely thrive on easily-mineralizable C that is found both in stover and, to a lesser extent, in PyOM. In contrast, we also identified unique PyOM-responders, which may respond to substrates such as polyaromatic C. In particular, members ofGemmatimonadetestended to increase in relative abundance in response to PyOM but not to fresh organic matter. We identify taxa to target for future investigations of the mechanistic underpinnings of ecological phenomena associated with PyOM additions to soil.
A reductionist approach to model photosynthetic self-regulation in eukaryotes in response to light
Authors: Matuszyńska Anna B. , Ebenhöh Oliver
Published: December 2015

Along with the development of several large-scale methods such as mass spectrometry or micro arrays, genome wide models became not only a possibility but an obvious tool for theoretical biologists to integrate and analyse complex biological data. Nevertheless, incorporating the dynamics of photosynthesis remains one of the major challenges while reconstructing metabolic networks of plants and other photosynthetic organisms. In this review, we aim to provide arguments that small-scale models are still a suitable choice when it comes to discover organisational principles governing the design of biological systems. We give a brief overview of recent modelling efforts in understanding the interplay between rapid, photoprotective mechanisms and the redox balance within the thylakoid membrane, discussing the applicability of a reductionist approach in modelling self-regulation in plants, and outline possible directions for further research.
Multiscale Modeling of Cancer
Authors: Norton Kerri-Ann , McCabe Pryor Meghan , Popel Aleksander S.
Published: December 2015

Breast cancer remains the second leading cause of cancer death in women, exceeded only by lung cancer. Specifically, triple-negative breast cancer (TNBC) has the worst prognosis, as it is more invasive and lacks estrogen, progesterone, and HER2 receptors that can be targeted with therapies. Due to the need for effective therapies for this type of breast cancer, it is critical to develop methods to (1) understand how TNBC progresses and (2) facilitate development of effective therapies. Here, we describe a multiscale model focusing on tumor formation. Our approach uses multiple scales to investigate the progression and possible treatments of tumors.
Origins of polarization-dependent anisotropic X-ray scattering from organic thin films
Authors: Gann Eliot , Collins Brian A. , Tang Maolong , Tumbleston John R. , Mukherjee Subrangsu , Ade Harald
Published: December 2015

Organic thin films that have no overall in-plane directional ordering often nonetheless produce anisotropic scattering patterns that rotate with the polarization of incident resonant X-rays. Isotropic symmetry is broken by local correlations between molecular orientation and domain structure. Such examples of molecular alignment at domain interfaces and within the bulk of domains, which are both critical to fields such as organic electronics, are simulated and compared with experimental scattering. Anisotropic scattering patterns are found to allow unambiguous identification of the mechanism of local molecular orientation correlations and, as such, promise to be both distinct and complementary to isotropic scattering intensity as a general measure of thin film microstructure.
Synthesis, crystal structure and magnetic properties of a two-dimensional cyanide-based heterometallic coordination polymer with cationic piperazinium ligands: poly[aquatetra-μ2-cyanido-κ8C:N-dicyanido-κ2C-(piperazinium-κN4)cobalt(III)copper(II)]
Authors: Qin Ying-Lian , Yao Chen-Zhong , Yang Bin-Wu , Qin Jian-Fang , Gong Qiao-Juan
Published: December 2015

Cyanide as a bridge can be used to construct homo- and heterometallic complexes with intriguing structures and interesting magnetic properties. These ligands can generate diverse structures, including clusters, one-dimensional chains, two-dimensional layers and three-dimensional frameworks. The title cyanide-bridged CuII–CoIIIheterometallic compound, [CuIICoIII(CN)6(C4H11N2)(H2O)]n, has been synthesized and characterized by single-crystal X-ray diffraction analysis, magnetic measurement, thermal study, vibrational spectroscopy (FT–IR) and scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM–EDS). The crystal structure analysis revealed that it has a two-dimensional grid-like structure built up of [Cu(Hpip)(H2O)]3+cations (Hpip is piperazinium) and [Co(CN)6]3−anions that are linked through bridging cyanide ligands. The overall three-dimensional supramolecular network is expanded by a combination of interlayer O—H...N and N—H...O hydrogen bonds involving the coordinated water molecules and the N atoms of the nonbridging cyanide groups and monodentate cationic piperazinium ligands. A magnetic investigation shows that antiferromagnetic interactions exist in the title compound.
Crystal structure of bis(1,3-dimethoxyimidazolin-2-ylidene)silver(I) hexafluoridophosphate, N-heterocyclic carbene (NHC) complex
Authors: Rietzler Barbara , Laus Gerhard , Kahlenberg Volker , Schottenberger Herwig
Published: December 2015

The title salt, [Ag(C5H8N2O2)2]PF6, was obtained by deprotonation and metalation of 1,3-dimethoxyimidazolium hexafluoridophosphate using silver(I) oxide in methanol. The C—Ag—C angle in the cation is 178.1 (2)°, and the N—C—N angles are 101.1 (4) and 100.5 (4)°. The methoxy groups adopt ananticonformation. In the crystal, anions (A) are sandwiched between cations (C) in a layered arrangement {C…A…C}nstacked along [001]. Within aC…A…Clayer, the hexafluoridophosphate anions accept several C—H...F hydrogen bonds from the cationic complex.
Crystal structure of ethyl 3-(4-chlorophenyl)-5-[(E)-2-(dimethylamino)ethenyl]-1,2-oxazole-4-carboxylate
Authors: Efimov Ilya , Slepukhin Pavel , Bakulev Vasiliy
Published: December 2015

In the title compound, C16H17ClN2O3, two molecules,AandB, with different conformations, comprise the asymmetric unit. In moleculeA, the C=O group of the ester points away from the benzene ring [C—C—C=O = −170.8 (3)°], whereas in moleculeB, it points back towards the benzene ring [C—C—C=O = 17.9 (4)°]. The dihedral angles betweeen the oxazole and benzene rings also differ somewhat [46.26 (13) for moleculeAand 41.59 (13) for moleculeB]. Each molecule features an intramolecular C—H...O interaction, which closes anS(6) ring. In the crystal, theBmolecules are linked into [001]C(12) chains by weak C—H...Cl interactions.