bluuebunny/crossref_metadata_2025 huggingface dataset:
The evaluation of uterine artery embolization as a nonsurgical treatment option for adenomyosis
Authors: Wang Shaoguang , Meng Xiaomei , Dong Yaozhong
Published: December 2015

Objective

To evaluate the safety and efficacy of uterine artery embolization (UAE) for the treatment of adenomyosis.

Methods

A prospective study was performed at Yuhuangding Hospital, China, between January 2012 and December 2013, enrolling premenopausal patients diagnosed with adenomyosis. All patients were treated with bilateral UAE using 500–700‐μm tris‐acryl gelatin microspheres. At baseline, and 3, 6, and 12 months after UAE, magnetic resonance imaging was used to assess uterine volume and patient‐assessed improvements in dysmenorrhea were recorded. Any complications and adverse events were reported.

Results

In total, 117 patients with adenomyosis were enrolled. The bilateral UAE procedure was successful in 115 (98.3%) patients, who were able to return to normal activity within 1 week of treatment. At 12‐month follow‐up, a median 51.0% reduction in uterine volume from baseline was recorded (P = 0.005). Marked and moderate improvements in dysmenorrhea symptoms were reported by 64 (55.7%) and 31 (27.0%) participants, respectively. Pelvic pain of varying intensity was reported by 112 (97.4%) patients but was managed with analgesia. Persistent amenorrhea was experienced by 2 (1.7%) individuals following treatment. Patients did not encounter any new gynecologic or general complications following UAE treatment.

Conclusion

UAE could be considered as a minimally invasive treatment option for patients with adenomyosis. Further research to compare the efficacy and safety of UAE with conventional hysterectomy is warranted.
Learning from Anangu Histories: Population Centralisation and Decentralisation Influences and the Provision of Schooling in Tri-state Remote Communities
Authors: Osborne Sam
Published: December 2015

Remote Australian Aboriginal and Torres Strait Islander schools and communities are diverse and complex sites shaped by contrasting geographies, languages, histories and cultures, including historical and ongoing relationships with colonialism, and connected yet contextually unique epistemologies, ontologies and cosmologies.This paper explores the history of Anangu (Pitjantjatjara, Yankunytjatjara, Ngaanyatjarra and Ngaatjatjarra) populations, including the establishment of incorporated communities and schools across the tri-state remote region of central Australia. This study will show that Anangu have a relatively recent contact history with Europeans and Anangu experiences of engagement with colonisation and schooling are diverse and complex.By describing historical patterns of population centralisation and decentralisation, I argue that schooling and broader education policies need to be contextually responsive to Anangu histories, values, ontologies and epistemologies in order to produce an education approach that resists colonialist social models and assumptions and instead, works more effectively towards a broader aim of social justice. Through assisting educators and policy makers to acquire a clearer understanding of Anangu histories, capacities and struggle, I hope to inform a more nuanced, contextually responsive and socially-just consideration of the provision of Western education in the tri-state region.
Hawaii's Swelling Lava Lake Charts a Volcano's Hidden Plumbing
Authors: Betz Eric
Published: December 2015

Geophysicists used unique seismic signatures to track the cyclic rise and fall of lava inside Hawai'i Volcanoes National Park's Overlook crater.
Chappell, Jones, and McBean Receive 2015 Ambassador Award
Authors:   AGU
Published: December 2015

Charles R. Chappell, Lucile Jones, and Gordon McBean were awarded the 2015 Ambassador Award at the American Geophysical Union Fall Meeting Honors Ceremony, held on 16 December 2015 in San Francisco, Calif. The award is in recognition for "outstanding contributions to the following area(s): societal impact, service to the Earth and space community, scientific leadership, and promotion of talent/career pool."
C2238/αANP modulates apolipoprotein E through Egr-1/miR199a in vascular smooth muscle cells in vitro
Authors: Stanzione R , Sciarretta S , Marchitti S , Bianchi F , Di Castro S , Scarpino S , Cotugno M , Frati G , Volpe M , Rubattu S
Published: December 2015

Subjects carrying the T2238C ANP gene variant have a higher risk to suffer a stroke or myocardial infarction. The mechanisms through which T2238C/αANP exerts detrimental vascular effects need to be fully clarified. In the present work we aimed at exploring the impact of C2238/αANP (mutant form) on atherosclerosis-related pathways. As a first step, an atherosclerosis gene expression macroarray analysis was performed in vascular smooth muscle cells (VSMCs) exposed to either T2238/αANP (wild type) or C2238/αANP. The major finding was that apolipoprotein E (ApoE) gene expression was significantly downregulated by C2238/αANP and it was upregulated by T2238/αANP. We subsequently found that C2238/αANP induces ApoE downregulation through type C natriuretic peptide receptor (NPR-C)-dependent mechanisms involving the upregulation of miR199a-3p and miR199a-5p and the downregulation of DNAJA4. In fact, NPR-C knockdown rescued ApoE level. Upregulation of miR199a by NPR-C was mediated by a reactive oxygen species-dependent increase of the early growth response protein-1 (Egr-1) transcription factor. In fact, Egr-1 knockdown abolished the impact of C2238/αANP on ApoE and miR199a. Of note, downregulation of ApoE by C2238/αANP was associated with a significant increase in inflammation, apoptosis and necrosis that was completely rescued by the exogenous administration of recombinant ApoE. In conclusion, our study dissected a novel mechanism of vascular damage exerted by C2238/αANP that is mediated by ApoE downregulation. We provide the first demonstration that C2238/αANP downregulates ApoE in VSMCs through NPR-C-dependent activation of Egr-1 and the consequent upregulation of miR199a. Restoring ApoE levels could represent a potential therapeutic strategy to counteract the harmful effects of C2238/αANP.
Myocyte-derived Tnfsf14 is a survival factor necessary for myoblast differentiation and skeletal muscle regeneration
Authors: Waldemer-Streyer R J , Chen J
Published: December 2015

Adult skeletal muscle tissue has a uniquely robust capacity for regeneration, which gradually declines with aging or is compromised in muscle diseases. The cellular mechanisms regulating adult myogenesis remain incompletely understood. Here we identify the cytokine tumor necrosis factor superfamily member 14 (Tnfsf14) as a positive regulator of myoblast differentiation in culture and muscle regeneration in vivo. We find that Tnfsf14, as well as its cognate receptors herpes virus entry mediator (HVEM) and lymphotoxin β receptor (LTβR), are expressed in both differentiating myocytes and regenerating myofibers. Depletion of Tnfsf14 or either receptor inhibits myoblast differentiation and promotes apoptosis. Our results also suggest that Tnfsf14 regulates myogenesis by supporting cell survival and maintaining a sufficient pool of cells for fusion. In addition, we show that Akt mediates the survival and myogenic function of Tnfsf14. Importantly, local knockdown of Tnfsf14 is found to impair injury-induced muscle regeneration in a mouse model, affirming an important physiological role for Tnfsf14 in myogenesis in vivo. Furthermore, we demonstrate that localized overexpression of Tnfsf14 potently enhances muscle regeneration, and that this regenerative capacity of Tnfsf14 is dependent on Akt signaling. Taken together, our findings reveal a novel regulator of skeletal myogenesis and implicate Tnfsf14 in future therapeutic development.
Obesity and cancer, a case for insulin signaling
Authors: Poloz Y , Stambolic V
Published: December 2015

Obesity is a worldwide epidemic, with the number of overweight and obese individuals climbing from just over 500 million in 2008 to 1.9 billion in 2014. Type 2 diabetes (T2D), cardiovascular disease and non-alcoholic fatty liver disease have long been associated with the obese state, whereas cancer is quickly emerging as another pathological consequence of this disease. Globally, at least 2.8 million people die each year from being overweight or obese. It is estimated that by 2020 being overweight or obese will surpass the health burden of tobacco consumption. Increase in the body mass index (BMI) in overweight (BMI>25 kg/m2) and obese (BMI>30 kg/m2) individuals is a result of adipose tissue (AT) expansion, which can lead to fat comprising >50% of the body weight in the morbidly obese. Extensive research over the last several years has painted a very complex picture of AT biology. One clear link between AT expansion and etiology of diseases like T2D and cancer is the development of insulin resistance (IR) and hyperinsulinemia. This review focuses on defining the link between obesity, IR and cancer.
Simultaneous determination of indoor ammonia pollution and its biological metabolite in the human body with a recyclable nanocrystalline lanthanide-functionalized MOF
Authors: Hao Ji-Na , Yan Bing
Published: December 2015

A nanocrystalline lanthanide-functionalized MOF was fabricated and developed as a recyclable fluorescent sensor for simultaneous determination of indoor ammonia pollution and its biological metabolite (urinary urea).
Anderson localization of light in a colloidal suspension (TiO2@silica)
Authors: Jimenez-Villar Ernesto , da Silva Iran F. , Mestre Valdeci , de Oliveira Paulo C. , Faustino Wagner M. , de Sá Gilberto F.
Published: December 2015

Localization of light in a colloidal suspension: a new avenue to manufacture novel photochemical reactors, powerful sensing tools and other advanced photonic devices.
Infection-resistant styrenic thermoplastic elastomers that can switch from bactericidal capability to anti-adhesion
Authors: Yuan Shuaishuai , Li Yonggang , Luan Shifang , Shi Hengchong , Yan Shunjie , Yin Jinghua
Published: December 2015

Infection-resistant styrenic thermoplastic elastomers that can switch from bactericidal capability to anti-adhesion are facilely chloromethylated, followed by quaternization with methyl 3-(dimethylamino) propionate.
A thermally activated delayed blue fluorescent emitter with reversible externally tunable emission
Authors: Rajamalli Pachaiyappan , Senthilkumar Natarajan , Gandeepan Parthasarathy , Ren-Wu Chen-Zheng , Lin Hao-Wu , Cheng Chien-Hong
Published: December 2015

A TADF material containing a benzoylpyridine core and twometacarbazolyl groups shows externally switchable emission in the solid states and a high external quantum efficiency of 18.4% when used as a blue dopant in OLEDs.
Synthesis, structure and optical properties of two novel luminescent polar dysprosium metal–organic frameworks: [(CH3)2NH2][Dy(HCOO)4] and [N2H5][Dy(HCOO)4]
Authors: Ptak Maciej , Mączka Mirosław , Gągor Anna , Głuchowski Paweł , Macalik Lucyna
Published: December 2015

We report the structures and optical properties of two novel dysprosium formates templated by protonated amines.
Aural Rehabilitation in Private Practice
Authors: Jessen Dusty
Published: December 2015

Aural rehabilitation refers to sensory management, auditory speech perception training, and counseling services provided to those with hearing loss and their communication partners. The goal of aural rehabilitation is to reduce the impact that hearing loss has on communication and daily function. There is ample evidence confirming the effectiveness of aural rehabilitation, however, comprehensive aural rehabilitation services are rarely offered in the private practice setting. Lack of time, compliance, and reimbursement have been suggested as possible reasons for the rare provision of aural rehabilitation services. The purpose of this article is to provide the reader with a simple framework for efficiently incorporating aural rehabilitation services into a busy private practice. It is suggested that both client and clinician compliance will improve when clinicians become proficient with a few select tools in the areas of assessment, education and counseling, auditory training, and follow-up. In today's changing marketplace, it is critical for private practice clinicians to set themselves apart from the commodity options by offering comprehensive aural rehabilitation services.
Global Speech-Language Health: Belize
Authors: Jaramillo M. Elizabeth
Published: December 2015

This independent field experience in global health explores the application of health promotion and service delivery models from the field of public health to speech-language services through descriptive research of the case in southern Belize. This project explores first steps in global speech-language health outreach for children living in very limited resource settings. Global speech-language health outreach includes community-wide interventions, fostering collaboration in the community and internationally, health education, building on local resources to expand health services, and special education program development. This project makes the assumption that a rich language environment may be a determinant of speech-language health. Speech-language interventions that enrich the linguistic environment may be a strong starting point for regions with very limited access to speech-language services. Therefore, this project looks at targeting social and environmental factors that influence language and literacy skills. The aim is to raise awareness of pediatric speech-language disability in southern Belize, with the ultimate goal of increasing school and community participation of children with speech-language disabilities. The purpose of this project is to explore points of entry for population-wide, environment-enriching, and culturally relevant intervention targeting communication and academic growth, in a limited resource setting. Furthermore, this project describes barriers to speech-language services and interventions in southern Belize.
Vocal Performance Teachers and Hearing Loss
Authors: Gunnell Vance , Larsen Jeff
Published: December 2015

Hearing thresholds and distortion product otoacoustic emissions were measured for teachers of vocal performance who were gathered for a national conference. Results showed mean audiometric thresholds to be consistent with noise induced hearing loss, more than what would be expected with normal aging. Years of instruction and age were considered as factors in the hearing loss observed. It was concluded that hearing conservation should be initiated with this group to help raise awareness and protect them from hearing loss due to occupational noise exposure.
Crystal structure and magnetic exchange in La1−2xSr2xMn1−xSbxO3 (x ≤ 0.2) solid solutions
Authors: Karpinsky D. V. , Troyanchuk I. O. , Silibin M. V. , Gavrilov S. A. , Bushinsky M. V. , Sikolenko V. , Sirenko V. , Tebbens D.
Published: December 2015

The crystal structure and magnetic properties of the stoichiometric compounds La1−2xSr2xMn1−xSbxO3 (0.1 ≤ x ≤ 0.2) with manganese ions in the 3+ oxidation state are studied. These compounds exhibit rhombohedral structure at room temperatures, which transforms upon cooling into an orthorhombic structure without any signature of orbital ordering. The compounds with x ≤ 0.2 reveal a ferromagnetic ordering; their magnetization decreases with increasing the concentration of substitution ions. It is suggested that the observed ferromagnetism originates from the breakdown of orbital ordering and significant hybridization between the eg orbitals of Mn3+ and 2p orbitals of oxygen.
Rapid distortion analysis of high speed homogeneous turbulence subject to periodic shear
Authors: Bertsch Rebecca L. , Girimaji Sharath S.
Published: December 2015

The effect of unsteady shear forcing on small perturbation growth in compressible flow is investigated. In particular, flow-thermodynamic field interaction and the resulting effect on the phase-lag between applied shear and Reynolds stress are examined. Simplified linear analysis of the perturbation pressure equation reveals crucial differences between steady and unsteady shear effects. The analytical findings are validated with numerical simulations of inviscid rapid distortion theory (RDT) equations. In contrast to steadily sheared compressible flows, perturbations in the unsteady (periodic) forcing case do not experience an asymptotic growth phase. Further, the resonance growth phenomenon found in incompressible unsteady shear turbulence is absent in the compressible case. Overall, the stabilizing influence of both unsteadiness and compressibility is compounded leading to suppression of all small perturbations. The underlying mechanisms are explained.
Low temperature magnetic properties and spin dynamics in single crystals of Cr8Zn antiferromagnetic molecular rings
Authors: Adelnia Fatemeh , Chiesa Alessandro , Bordignon Sara , Carretta Stefano , Ghirri Alberto , Candini Andrea , Cervetti Christian , Evangelisti Marco , Affronte Marco , Sheikin Ilya , Winpenny Richard , Timco Grigore , Borsa Ferdinando , Lascialfari Alessandro
Published: December 2015

A detailed experimental investigation of the effects giving rise to the magnetic energy level structure in the vicinity of the level crossing (LC) at low temperature is reported for the open antiferromagnetic molecular ring Cr8Zn. The study is conducted by means of thermodynamic techniques (torque magnetometry, magnetization and specific heat measurements) and microscopic techniques (nuclear magnetic resonance line width, nuclear spin lattice, and spin-spin relaxation measurements). The experimental results are shown to be in excellent agreement with theoretical calculations based on a minimal spin model Hamiltonian, which includes a Dzyaloshinskii-Moriya interaction. The first ground state level crossing at μ0Hc1 = 2.15 T is found to be an almost true LC while the second LC at μ0Hc2 = 6.95 T has an anti-crossing gap of Δ12 = 0.19 K. In addition, both NMR and specific heat measurements show the presence of a level anti-crossing between excited states at μ0H = 4.5 T as predicted by the theory. In all cases, the fit of the experimental data is improved by introducing a distribution of the isotropic exchange couplings (J), i.e., using a J strain model. The peaks at the first and second LCs in the nuclear spin-lattice relaxation rate are dominated by inelastic scattering and a value of Γ ∼ 1010 rad/s is inferred for the life time broadening of the excited state of the open ring, due to spin phonon interaction. A loss of NMR signal (wipe-out effect) is observed for the first time at LC and is explained by the enhancement of the spin-spin relaxation rate due to the inelastic scattering.
Anomalies of magnetoresistance in Ce-based heavy fermion compounds
Authors: Sluchanko N. E. , Bogach A. V. , Anisimov M. A. , Glushkov V. V. , Demishev S. V. , Samarin N. A. , Chistyakov O. D. , Burkhanov G. S. , Gabani S. , Flachbart K.
Published: December 2015

Magnetoresistance Δρ(H,T) of several heavy-fermion compounds, CeAl2, CeAl3 and CeCu6, substitutional solid solutions with quantum critical behavior CeCu6–xAux (x = 0.1, 0.2) and alloys with magnetic ground state Ce(Al1–xMx)2 (M = Co, Ni, x ≤ 0.8) was studied in a wide range of temperatures (1.8–40 K) in magnetic fields up to 80 kOe. It was shown that a consistent interpretation of the field dependences of the resistance for both non-magnetic and magnetically ordered cerium-based intermetallic compounds with strong electron correlations can be achieved within the framework of an approach that accounts for scattering of charge carriers by localized magnetic moments in a metal matrix. Within this approach, three different components of the magnetoresistance of cerium intermetallic compounds were identified: the negative Brillouin contribution proportional to the local magnetization (−Δρ/ρ∼Mloc2), the alternating linear contribution (Δρ/ρ∼H) and the magnetic component, saturating in magnetic fields below 15 kOe. In the framework of the Yosida model for the cerium alloys under study, estimates of the local magnetic susceptibility χloc(H, T0) were obtained from the magnetoresistance data. Numerical differentiation of the magnetoresistance with respect to the magnetic field and analysis of the obtained d(Δρ/ρ)/dH=f(H,T) dependences allowed us to reconstruct the H–T magnetic phase diagrams of the strongly correlated electron systems under study as well as to examine the effects of spin polarization and renormalization of the electronic states on charge transport both in the regime of quantum critical behavior and in the magnetically ordered state.
Irreversible magnetization switching at the onset of superconductivity in a superconductor ferromagnet hybrid
Authors: Curran P. J. , Kim J. , Satchell N. , Witt J. D. S. , Burnell G. , Flokstra M. G. , Lee S. L. , Cooper J. F. K. , Kinane C. J. , Langridge S. , Isidori A. , Pugach N. , Eschrig M. , Bending S. J.
Published: December 2015

We demonstrate that the magnetic state of a superconducting spin valve, that is normally controlled with an external magnetic field, can also be manipulated by varying the temperature which increases the functionality and flexibility of such structures as switching elements. In this case, switching is driven by changes in the magnetostatic energy due to spontaneous Meissner screening currents forming in the superconductor below the critical temperature. Our scanning Hall probe measurements also reveal vortex-mediated pinning of the ferromagnetic domain structure due to the pinning of quantized stray fields in the adjacent superconductor. The ability to use temperature as well as magnetic field to control the local magnetisation structure raises the prospect of potential applications in magnetic memory devices.
Features of the electronic structure of FeTe compounds
Authors: Grechnev G. E. , Lyogenkaya A. A. , Panfilov A. S. , Logosha A. V. , Kotlyar O. V. , Gnezdilov V. P. , Makarova I. P. , Chareev D. A. , Mitrofanova E. S.
Published: December 2015

A theoretical and experimental study of the electronic structure and nature of the chemical bonds in FeTe compounds in antiferromagnetic  (AFM) and paramagnetic phases was carried out. It is established that the nature of the chemical bonds is mainly metallic, and the presence of covalent bonds Fe-Te and Te-Te helps to stabilize the structural distortions of the tetragonal phase of FeTe in the low-temperature region. It is found that the bicollinear AFM structure corresponds to the ground state of the FeTe compound and the calculated value of the magnetic moment MFe = −2.4μB is in good agreement with the data from neutron diffraction measurements. At the same time, the Fermi surface (FS) of the low-temperature AFM phase is radically different from the FS of the paramagnetic FeTe. Reconstructing the FS can lead to a sign change of the Hall coefficient observed in FeTe. The calculation results serve as evidence of the fact that the electronic structures and magnetic properties of FeTe are well-described by the model of itinerant d-electrons and the density functional theory (DFT-GGA).
Synaptic plasticity functions in an organic electrochemical transistor
Authors: Gkoupidenis Paschalis , Schaefer Nathan , Strakosas Xenofon , Fairfield Jessamyn A. , Malliaras George G.
Published: December 2015

Synaptic plasticity functions play a crucial role in the transmission of neural signals in the brain. Short-term plasticity is required for the transmission, encoding, and filtering of the neural signal, whereas long-term plasticity establishes more permanent changes in neural microcircuitry and thus underlies memory and learning. The realization of bioinspired circuits that can actually mimic signal processing in the brain demands the reproduction of both short- and long-term aspects of synaptic plasticity in a single device. Here, we demonstrate the implementation of neuromorphic functions similar to biological memory, such as short- to long-term memory transition, in non-volatile organic electrochemical transistors (OECTs). Depending on the training of the OECT, the device displays either short- or long-term plasticity, therefore, exhibiting non von Neumann characteristics with merged processing and storing functionalities. These results are a first step towards the implementation of organic-based neuromorphic circuits.
Anomalous magnetic properties of the paramagnetic phase and spin polarons in manganese monosilicide
Authors: Demishev S. V. , Ishchenko T. V. , Samarin A. N.
Published: December 2015

We consider the field dependence of magnetization in the paramagnetic phase of manganese monosilicde, MnSi, which is characterized by an anomalously large effective magnetic moment μ* = 5.3μB, and a small saturation magnetization M0 = 0.3μB/Mn. It follows from the conducted analysis, that neither the theory of band magnetism, nor the cluster approach can explain the experimental data, but an adequate description is possible within the framework of the spin-polaron model, in which the spin-polaron is a quasi-bonded state of the band electron and localized magnetic moment of Mn. It is found that the inclusion of specific interaction for a simple ferrimagnet-like configuration that characterizes the spin-polaron, allows us to explain the experimental data, wherein the observed values of μ* are not associated with large localized magnetic moments in the sample volume. The possible methods of experimental verification of the spin-polaron model are analyzed, including experimentum crucis. The obtained results show that the paramagnetic phase of MnSi should be regarded as a phase in which its physical properties are determined by the magnetic inhomogeneities on a nanometer spatial scale.
Hyperpolarizability of two electron atoms under exponential cosine screened coulomb potential
Authors: Chaudhuri Supriya K. , Mukherjee Prasanta K. , Fricke Burkhard
Published: December 2015

Hyperpolarizability of two electron atoms He, Li+, Be2+, B3+, and C4+ embedded under quantum plasma environment has been calculated for the first time using exponential cosine screened coulomb potential (ECSCP) arising out of the interaction of atomic charge cloud with such an environment. Coupled Hartree-Fock theory within variational scheme has been utilised to estimate such nonlinear optical property for systematic variation of the screening parameter arising out of the coupling strength of the plasma with atomic charge cloud. Hyperpolarizability of the ions increases systematically with increase of the screening parameter. Results have been compared with respect to those obtained from the interaction of atomic systems with a Debye plasma environment giving rise to SCP. Interesting feature is observed for the polarizability and hyperpolarizability values under increasing screening parameters of ECSCP and SCP. Hyperpolarizability values for zero screening compare well with those available for the free ions.
Theory of the electron sheath and presheath
Authors: Scheiner Brett , Baalrud Scott D. , Yee Benjamin T. , Hopkins Matthew M. , Barnat Edward V.
Published: December 2015

Electron sheaths are commonly found near Langmuir probes collecting the electron saturation current. The common assumption is that the probe collects the random flux of electrons incident on the sheath, which tacitly implies that there is no electron presheath and that the flux collected is due to a velocity space truncation of the electron velocity distribution function (EVDF). This work provides a dedicated theory of electron sheaths, which suggests that they are not so simple. Motivated by EVDFs observed in particle-in-cell (PIC) simulations, a 1D model for the electron sheath and presheath is developed. In the model, under low temperature plasma conditions (Te≫Ti), an electron pressure gradient accelerates electrons in the presheath to a flow velocity that exceeds the electron thermal speed at the sheath edge. This pressure gradient generates large flow velocities compared to what would be generated by ballistic motion in response to the electric field. It is found that in many situations, under common plasma conditions, the electron presheath extends much further into the plasma than an analogous ion presheath. PIC simulations reveal that the ion density in the electron presheath is determined by a flow around the electron sheath and that this flow is due to 2D aspects of the sheath geometry. Simulations also indicate the presence of ion acoustic instabilities excited by the differential flow between electrons and ions in the presheath, which result in sheath edge fluctuations. The 1D model and time averaged PIC simulations are compared and it is shown that the model provides a good description of the electron sheath and presheath.
High-beta equilibria in tokamaks with pressure anisotropy and toroidal flow
Authors: Layden B. , Hole M. J. , Ridden-Harper R.
Published: December 2015

We extend previous analytical calculations of 2D high-β equilibria in order-unity aspect ratio tokamaks with toroidal flow to include pressure anisotropy, assuming guiding-center theory for a bi-Maxwellian plasma and the ideal MHD Ohm's law. Equilibrium solutions are obtained in the core region (which fills most of the plasma volume) and the boundary layer. We find that pressure anisotropy with p∥>p⊥ (p∥
Ωmin) were previously found to suppress the field-free region (diamagnetic hole) that exists in static isotropic high-β equilibria. We find that all equilibrium solutions with pressure anisotropy suppress the diamagnetic hole. For the static case with a volume-averaged toroidal beta of 70%, plasmas with max(p∥/p⊥)>α1=1.07 have equilibrium solutions. We find that α1 decreases with increasing toroidal flow speed, and above the flow threshold Ωmin we find α1=1, so that all p∥>p⊥ plasmas have equilibrium solutions. On the other hand, for p∥
p⊥, while the converse is true for p∥<p⊥.
Acoustic detection of cracks in the anvil of a large-volume cubic high-pressure apparatus
Authors: Yan Zhaoli , Chen Bin , Tian Hao , Cheng Xiaobin , Yang Jun
Published: December 2015

A large-volume cubic high-pressure apparatus with three pairs of tungsten carbide anvils is the most popular device for synthetic diamond production. Currently, the consumption of anvils is one of the important costs for the diamond production industry. If one of the anvils is fractured during the production process, the other five anvils in the apparatus may be endangered as a result of a sudden loss of pressure. It is of critical importance to detect and replace cracked anvils before they fracture for reduction of the cost of diamond production and safety. An acoustic detection method is studied in this paper. Two new features, nested power spectrum centroid and modified power spectrum variance, are proposed and combined with linear prediction coefficients to construct a feature vector. A support vector machine model is trained for classification. A sliding time window is proposed for decision-level information fusion. The experiments and analysis show that the recognition rate of anvil cracks is 95%, while the false-alarm rate is as low as 5.8 × 10−4 during a time window; this false-alarm rate indicates that at most one false alarm occurs every 2 months at a confidence level of 90%. An instrument to monitor anvil cracking was designed based on a digital signal processor and has been running for more than eight months in a diamond production field. In this time, two anvil-crack incidents occurred and were detected by the instrument correctly. In addition, no false alarms occurred.
Exchange bias in epitaxial and polycrystalline thin film Ru2MnGe/Fe bilayers
Authors: Balluff Jan , Meinert Markus , Schmalhorst Jan-Michael , Reiss Günter , Arenholz Elke
Published: December 2015

We report on thin film bilayers of the antiferromagnetic Heusler compound Ru2MnGe and Fe, as well as the resulting exchange bias field at low temperatures and its temperature dependence. Epitaxial Ru2MnGe/Fe bilayers show an exchange bias field up to 680 Oe at 3 K. For increasing temperatures, a linearly decreasing exchange bias field is found, which vanishes at 130 K. Furthermore, we grew polycrystalline Ru2MnGe showing an exchange bias field up to 540 Oe, which vanishes around 30 K. By adding a very thin intermediate layer of Mn, the exchange bias field for polycrystalline samples has been increased by about 40%. We discuss differences between the epitaxial and polycrystalline films regarding magnetic and crystallographic properties and compare our results to already published work on this system.
Dislocation confinement in the growth of Na flux GaN on metalorganic chemical vapor deposition-GaN
Authors: Takeuchi S. , Asazu H. , Imanishi M. , Nakamura Y. , Imade M. , Mori Y. , Sakai A.
Published: December 2015

We have demonstrated a GaN growth technique in the Na flux method to confine c-, (a+c)-, and a-type dislocations around the interface between a Na flux GaN crystal and a GaN layer grown by metalorganic chemical vapor deposition (MOCVD) on a (0001) sapphire substrate. Transmission electron microscopy (TEM) clearly revealed detailed interface structures and dislocation behaviors that reduced the density of vertically aligned dislocations threading to the Na flux GaN surface. Submicron-scale voids were formed at the interface above the dislocations with a c component in MOCVD-GaN, while no such voids were formed above the a-type dislocations. The penetration of the dislocations with a c component into Na flux GaN was, in most cases, effectively blocked by the presence of the voids. Although some dislocations with a c component in the MOCVD-GaN penetrated into the Na flux GaN, their propagation direction changed laterally through the voids. On the other hand, the a-type dislocations propagated laterally and collectively near the interface, when these dislocations in the MOCVD-GaN penetrated into the Na flux GaN. These results indicated that the dislocation propagation behavior was highly sensitive to the type of dislocation, but all types of dislocations were confined to within several micrometers region of the Na flux GaN from the interface. The cause of void formation, the role of voids in controlling the dislocation behavior, and the mechanism of lateral and collective dislocation propagation are discussed on the basis of TEM results.
The effects of magnetic and mechanical microstructures on the twinning stress in Ni-Mn-Ga
Authors: Faran Eilon , Benichou Itamar , Givli Sefi , Shilo Doron
Published: December 2015

The ferromagnetic 10M Ni-Mn-Ga alloy exhibits complex magnetic and mechanical microstructures, which are expected to form barriers for motion of macro twin boundaries. Here, the contributions of both microstructures to the magnitude of the twinning stress property are investigated experimentally. A series of uniaxial loading-unloading curves are taken under different orientation angles of a constant magnetic field. The different 180° magnetic domains microstructures that are formed across the twin boundary in each case are visualised using a magneto optical film. Analysis of the different loading curves and the corresponding magnetic microstructures show that the latter does not contribute to the barriers for twin boundary motion. In accordance, the internal resisting stress for twin boundary motion under any magnetic field can be taken as the twinning stress measured in the absence of an external field. In addition, a statistical analysis of the fine features in the loading profiles reveals that the barrier for twinning is associated with a μm sized characteristic length scale. This length scale corresponds to the typical thickness of micro-twinning laminates that constitute a mechanical microstructure. These findings indicate that the magnitude of the twinning stress in 10M Ni-Mn-Ga is determined by the characteristic fine twinned mechanical microstructure of this alloy.
Effect of hydrogen passivation on the photoluminescence of Tb ions in silicon rich silicon oxide films
Authors: Zatryb G. , Klak M. M. , Wojcik J. , Misiewicz J. , Mascher P. , Podhorodecki A.
Published: December 2015

In this work, silicon-rich silicon oxide films containing terbium were prepared by means of plasma enhanced chemical vapor deposition. The influence of hydrogen passivation on defects-mediated non-radiative recombination of excited Tb3+ ions was investigated by photoluminescence, photoluminescence excitation, and photoluminescence decay measurements. Passivation was found to have no effect on shape and spectral position of the excitation spectra. In contrast, a gradual increase in photoluminescence intensity and photoluminescence decay time was observed upon passivation for the main 5D4-7F5 transition of Tb3+ ions. This observation was attributed to passivation of non-radiative recombination defects centers with hydrogen. It was found that the number of emitted photons increases upon passivation as a result of two effects: (1) longer Tb3+ lifetime in the 5D4 excited state and (2) optical activation of new Tb3+ emitters. The obtained results were discussed and compared with other experimental reports.
The characterization and optimization of NIO1 ion source extraction aperture using a 3D particle-in-cell code
Authors: Taccogna F. , Minelli P. , Cavenago M. , Veltri P. , Ippolito N.
Published: December 2015

The geometry of a single aperture in the extraction grid plays a relevant role for the optimization of negative ion transport and extraction probability in a hybrid negative ion source. For this reason, a three-dimensional particle-in-cell/Monte Carlo collision model of the extraction region around the single aperture including part of the source and part of the acceleration (up to the extraction grid (EG) middle) regions has been developed for the new aperture design prepared for negative ion optimization 1 source. Results have shown that the dimension of the flat and chamfered parts and the slope of the latter in front of the source region maximize the product of production rate and extraction probability (allowing the best EG field penetration) of surface-produced negative ions. The negative ion density in the plane yz has been reported.
Error field penetration and locking to the backward propagating wave
Authors: Finn John M. , Cole Andrew J. , Brennan Dylan P.
Published: December 2015

In this letter, we investigate error field penetration, or locking, behavior in plasmas having stable tearing modes with finite real frequencies ωr in the plasma frame. In particular, we address the fact that locking can drive a significant equilibrium flow. We show that this occurs at a velocity slightly above v=ωr/k, corresponding to the interaction with a backward propagating tearing mode in the plasma frame. Results are discussed for a few typical tearing mode regimes, including a new derivation showing that the existence of real frequencies occurs for viscoresistive tearing modes, in an analysis including the effects of pressure gradient, curvature, and parallel dynamics. The general result of locking to a finite velocity flow is applicable to a wide range of tearing mode regimes, indeed any regime where real frequencies occur.
Beating effect between a thermoacoustic source and its mechanical partner
Authors: Wang Kai , Sun Daming , Zhang Jie , Zhang Ning , Luo Kai , Qiu Limin
Published: December 2015

Beating effects between a thermoacoustic source and its mechanical partner-a piston-spring oscillator are numerically predicted and experimentally observed in the free-decay process. Through analyzing the indicator diagram, periodic energy transfer characteristics between a thermoacoustic source and its mechanical partner during the beating oscillation are revealed and analyzed. The oscillation frequency is found to split into two modes intrinsically even when the resonance frequencies are initially tuned to be the same. The patterns and frequencies of the beating oscillations are sensitively affected by the characteristics of acoustic sources. The study sheds light on the underlying mechanisms of beating oscillations occurred in thermoacoustic systems with multiple resonant sub-units.
Equivalent circuit model of converse magnetoelectric effect for the tri-layer magnetoelectric laminates with thermal and stress loadings
Authors: Zhou Hao-Miao , Li Meng-Han , Liu Hui , Cui Xiao-Le
Published: December 2015

For the converse magnetoelectric coupling effect of the piezoelectric/magnetostrictive/piezoelectric tri-layer symmetric magnetoelectric laminates, based on the nonlinear thermo-magneto-mechanical constitutive equations of the giant magnetostrictive materials and the thermo-electro-mechanical constitutive equations of the piezoelectric materials, according to Newton’s second law and the magnetic circuit theorem, an equivalent circuit is established. Then an expression of the converse magnetoelectric coefficient describing nonlinear thermo-magneto-electro-mechanical coupling is established. The curve of the nonlinear converse magnetoelectric coefficient versus the bias magnetic field, is predicted effectively by the expression, and the predictions are in good agreement with the experimental result both qualitatively and quantitatively. Furthermore, the model can predict the complex influences of the bias magnetic field, the stress and the ambient temperature on the converse magnetoelectric coefficient. It can be found from these predictions that the converse magnetoelectric coefficient decreases with the increasing temperature and increases with the increasing tensile stress. Under the common effect of the ambient temperature and the stress, it is also found that the converse magnetoelectric coefficient changes sharply with the ambient temperature when the tensile stress is applied on the laminates, but it has a good stability of temperature when a large compressive stress is applied. Therefore, this work contributes to the researches on the giant converse magnetoelectric coefficient and the designs of magnetoelectric devices based on the converse magnetoelectric coupling.
Heating based model analysis for explosive emission initiation at metal cathodes
Authors: Majzoobi A. , Joshi R. P. , Neuber A. , Dickens J.
Published: December 2015

This contribution presents a model analysis for the initiation of explosive emission; a phenomena that is observed at cathode surfaces under high current densities. Here, localized heating is quantitatively evaluated on ultrashort time scales as a potential mechanism that initiates explosive emission, based on a two-temperature, relaxation time model. Our calculations demonstrate a strong production of nonequilibrium phonons, ultimately leading to localized melting. Temperatures are predicted to reach the cathode melting point over nanosecond times within the first few monolayers of the protrusion. This result is in keeping with the temporal scales observed experimentally for the initiation of explosive emission.
Magnetic nanobeads present during enzymatic amplification and labeling for a simplified DNA detection protocol based on AC susceptometry
Authors: Bejhed Rebecca S. , Strømme Maria , Svedlindh Peter , Ahlford Annika , Strömberg Mattias
Published: December 2015

Magnetic biosensors are promising candidates for low-cost point-of-care biodiagnostic devices. For optimal efficiency it is crucial to minimize the time and complexity of the assay protocol including target recognition, amplification, labeling and read-out. In this work, possibilities for protocol simplifications for a DNA biodetection principle relying on hybridization of magnetic nanobeads to rolling circle amplification (RCA) products are investigated. The target DNA is recognized through a padlock ligation assay resulting in DNA circles serving as templates for the RCA process. It is found that beads can be present during amplification without noticeably interfering with the enzyme used for RCA (phi29 polymerase). As a result, the bead-coil hybridization can be performed immediately after amplification in a one-step manner at elevated temperature within a few minutes prior to read-out in an AC susceptometer setup, i.e. a combined protocol approach. Moreover, by recording the phase angle ξ = arctan(χ″/χ′), where χ and χ″ are the in-phase and out-of-phase components of the AC susceptibility, respectively, at one single frequency the total assay time for the optimized combined protocol would be no more than 1.5 hours, often a relevant time frame for diagnosis of cancer and infectious disease. Also, applying the phase angle method normalization of AC susceptibility data is not needed. These findings are useful for the development of point-of-care biodiagnostic devices relying on bead-coil binding and magnetic AC susceptometry.
Terahertz filter integrated with a subwavelength structured antireflection coating
Authors: Woo Jeong Min , Kim Dae-Seon , Kim Dong-Ju , Jang Jae-Hyung
Published: December 2015

Micro-pyramid shaped subwavelength structures (SWSs) were integrated on both sides of a terahertz (THz) filter by means of stamping methods. Two silicon-based stamping molds fabricated via crystallographic wet etching were utilized to replicate SWSs onto cyclo-olefin copolymer (COC) films coated onto both sides of a THz filter at the same time. The SWSs act as an broadband antireflection coating to reduce the surface reflection loss in a frequency range of 0.2 THz to 1.4 THz. Compared to a THz filter without SWSs, the filter integrated with double-sided SWSs exhibits a low standing wave ratio inside the substrate and THz signal transmission enhancement of up to 10.8%.
Improvement of stability of sinusoidally driven atmospheric pressure plasma jet using auxiliary bias voltage
Authors: Kim Hyun-Jin , Kim Jae Young , Kim Jae Hyun , Kim Dong Ha , Lee Duck-Sik , Park Choon-Sang , Park Hyung Dal , Shin Bhum Jae , Tae Heung-Sik
Published: December 2015

In this study, we have proposed the auxiliary bias pulse scheme to improve the stability of atmospheric pressure plasma jets driven by an AC sinusoidal waveform excitation source. The stability of discharges can be significantly improved by the compensation of irregular variation in memory voltage due to the effect of auxiliary bias pulse. From the parametric study, such as the width, voltage, and onset time of auxiliary bias pulse, it has been demonstrated that the auxiliary bias pulse plays a significant role in suppressing the irregular discharges caused by the irregular variation in memory voltage and stable discharge can be initiated with the termination of the auxiliary bias pulse. As a result of further investigating the effects of the auxiliary pulse scheme on the jet stability under various process conditions such as the distance between the jet head and the counter electrode, and carrier gas flow, the jet stability can be improved by adjusting the amplitude and number of the bias pulse depending on the variations in the process conditions.
Polarization rotator of arbitrary angle based on simple slot-array
Authors: Liu Xiaoming , Cao Xiaohang , Yu Junsheng , Chen Xiaodong , Yao Yuan , Qi Limei , Chen Zhijiao , Zhou Jun
Published: December 2015

A novel polarization rotator of arbitrary angle was proposed and realized based on simple slot arrays. To achieve the rotation of an arbitrary angle α, the slots on the first layer have to be at an angle of α to the slots on the second layer. Consequently, 90° rotation can be realized using two perpendicularly oriented slot arrays, which overturns the conventional notion of that perpendicular slot arrays are not possible to pass electromagnetic wave. In addition, such structure provides the same bandwidth comparing to its counterpart utilized for frequency selective surface (FSS). Furthermore, such structure is much easier to be fabricated compared to the substrate integrated waveguide (SIW) array. Moreover, low insertion loss can be achieved based on metallic material.
Three groups close the loopholes in tests of Bell’s theorem
Authors: Miller Johanna L.
Published: December 2015

Until now, the quintessential demonstration of quantum entanglement has required extra assumptions.
Thermodynamic simulations explain the Moon’s composition
Authors: Wilson R. Mark
Published: December 2015

According to the simulations, more than half of the Moon accreted from volatile-poor molten rock that orbited Earth for decades following a giant impact.
Europeans shine in weather forecasting
Authors: Kramer David
Published: December 2015

The US global model lags the performance of two European competitors in predicting weather up to two weeks ahead.