bluuebunny/crossref_metadata_2025 huggingface dataset:
REPUTATION AND OPTIMAL CONTRACTS FOR CENTRAL BANKERS
Authors: Huang Kevin X. D. , Tian Guoqiang
Published: June 2011

We implement optimal economic outcomes at the lowest social cost by combining reputation and contracting mechanisms to overcome the time-inconsistency problem of monetary policy associated with an inflation bias. We characterize the conditions under which the reputation force alone induces a central bank to behave in a socially optimal way. When these conditions fail, an incentive contract is invoked, whose cost is significantly reduced by the presence of the reputation force. The contract poses a penalty threat that is a concave function of wage growth, which in equilibrium is tied to expected rather than realized inflation, with a global maximum that provides the least upper bound on all threatened penalties. This bound can be used as a uniform penalty threat to achieve optimal economic outcomes and still, for moderate to large shocks, its magnitude can be much smaller than the size of the transfers required by the standard contracts that are linear functions of realized inflation rates. Further, under both the concave and the uniform penalty threats, the central bank will behave in the socially optimal way and no transfer is materialized in equilibrium. Thus our hybrid mechanism solves the time-inconsistency problem while leaving the central bank with complete discretion to respond to new circumstances, without any reputation cost or penalty threatened by the contract actually invoked along the equilibrium path.
Deep Tissue Fluorescent Imaging in Scattering Specimens Using Confocal Microscopy
Authors: Clendenon Sherry G. , Young Pamela A. , Ferkowicz Michael , Phillips Carrie , Dunn Kenneth W.
Published: June 2011

In scattering specimens, multiphoton excitation and nondescanned detection improve imaging depth by a factor of 2 or more over confocal microscopy; however, imaging depth is still limited by scattering. We applied the concept of clearing to deep tissue imaging of highly scattering specimens. Clearing is a remarkably effective approach to improving image quality at depth using either confocal or multiphoton microscopy. Tissue clearing appears to eliminate the need for multiphoton excitation for deep tissue imaging.
Radiation and thermal effects on polymeric immobilization devices used in patients submitted to radiotherapy
Authors: Pereira-Loch C. , Benavides R. , Lima M. Fogliato S. , Huerta B.M.
Published: June 2011

Immobilization devices in radiotherapy are made of a soft plastic easy to mould when immersed in hot water. Same item is usually used for 6 patients (according to protocol), but at Hospital Sao Jose (HSJ) they have been showing some deformation during the re-utilization process. The latter is the reason for this research where devices were treated with 6 thermal conditions, 6 irradiation procedures and the joint effect of both treatments. DSC, TGA and WAXD indicated devices are made of polycaprolactone (PCL), but no signs of degradation, except a slight variation in crystalinity; however, mechanical properties by means of Young’s modulus steadily increase its values through number of treatments up to a 20%. Activation energy (Ea) obtained by multi-ramps of TGA-Arrhenius evaluated for the most treated samples (6th treatment) indicates that temperature facilitates degradation while irradiation and joint treatments enhance the stability of PCL, apparently by crosslinking.
E‐cadherin, a new mixer in the Yamanaka cocktail
Authors: Lowry William E
Published: June 2011

A paper published in May in EMBO reports by Redmer et al demonstrates that expression of E‐cadherin together with three of the Yamanaka factors (Sox2, Klf4 and c‐Myc) induces reprogramming of murine fibroblasts, even in the absence of Oct4.
Early plume and shock wave dynamics in atmospheric-pressure ultraviolet-laser ablation of different matrix-assisted laser ablation matrices
Authors: Schmitz Thomas A. , Koch Joachim , Günther Detlef , Zenobi Renato
Published: June 2011

Pulsed laser ablation of molecular solids is important for identification and quantification in (bio-)organic mass spectrometry, for example using matrix-assisted laser desorption/ionization (MALDI). Recently, there has been a major shift to using MALDI and related laser ablation/post-ionization methods at atmospheric pressure. However, the underlying laser ablation processes, in particular early plume formation and expansion, are still poorly understood. Here, we present a study of the early ablation processes on the ns-time scale in atmospheric pressure UV-laser ablation of anthracene as well as of different common MALDI matrices such as 2,5-dihydroxybenzoic acid (2,5-DHB), α-cyano-4-hydroxycinnamic acid and sinapinic acid. Material release as well as the formation and expansion of hemi-spherical shock waves were studied by shadowgraphy with high temporal resolution (∼5 ns). The applicability of the classical Taylor-Sedov model for expansion of strong shock waves (“point-blast model”), as well as the drag force model, were evaluated to mathematically describe the observed shock wave propagation. The time- and energy-dependent expansion of the shock waves could be described using a Taylor-Sedov scaling law of the form R ∝ tq, when a q-exponent of ∼0.5 instead of the theoretical value of q = 0.4 was found, indicating a faster expansion than expected. The deviations from the ideal value of q were attributed to the non-negligible influence of ambient pressure, a weak versus strong shock regime, and additional acceleration processes present in laser ablation that surpass the limit of the point-blast model. The onset of shock wave formation at a fluence of ∼15–30 mJ/cm2 for the compounds investigated coincides with the onset of bulk material release, whereas, pure desorption below this fluence threshold did not lead to features visible in shadowgraphy.
Stability of DNA-linked nanoparticle crystals: Effect of number of strands, core size, and rigidity of strand attachment
Authors: Padovan-Merhar Olivia , Lara Fernando Vargas , Starr Francis W.
Published: June 2011

Three-dimensional ordered lattices of nanoparticles (NPs) linked by DNA have potential applications in novel devices and materials, but most experimental attempts to form crystals result in amorphous packing. Here we use a coarse-grained computational model to address three factors that impact the stability of bcc and fcc crystals formed by DNA-linked NPs : (i) the number of attached strands to the NP surface, (ii) the size of the NP core, and (iii) the rigidity of the strand attachment. We find that allowing mobility in the attachment of DNA strands to the core NP can very slightly increase or decrease melting temperature TM. Larger changes to TM result from increasing the number of strands, which increases TM, or by increasing the core NP diameter, which decreases TM. Both results are consistent with experimental findings. Moreover, we show that the behavior of TM can be quantitatively described by the model introduced previously [F. Vargas Lara and F. W. Starr, Soft Matter, 7, 2085 (2011)]10.1039/c0sm00989j.
Elucidating negative capacitance in light-emitting diodes using an advanced semiconductor device theory
Authors: Li Y. , Wang C. D. , Feng L. F. , Zhu C. Y. , Cong H. X. , Li D. , Zhang G. Y.
Published: June 2011

The capacitance characteristics of light emitting diodes (LEDs) are accurately measured using a method based on an alternating-current small signal, together with direct current I-V plot. All measured LEDs display negative capacitance (NC) at large forward bias. By analyzing the dependence of capacitance on both forward bias and frequency, an accurate expression for describing NC was obtained. This expression is in conflict with Shockley’s p-n junction theory, which only describes increasing diffusion capacitance and does not allow NC. Using an advanced p-n junction theory developed by Hess and Laux, the dependence of NC on both voltage and frequency are described quantitatively.
Electro-optic and dielectric characterization of ferroelectric films for high-speed optical waveguide modulators
Authors: Masuda Shin , Seki Atsushi , Shiota Kazunori , Hara Hideo , Masuda Yoichiro
Published: June 2011

We investigate the electro-optic properties and high-frequency relative dielectric constants of epitaxially grown lanthanum-modified lead zirconate titanate (PLZT) and polycrystalline barium titanate (BaTiO3) films in a high-frequency range of up to 40 GHz for designing a high-speed ferroelectric thin-film modulator. We also demonstrate a ferroelectric thin-film Mach-Zehnder-type waveguide modulator using the epitaxially grown PLZT film. The use of a composite structure with a low dielectric coefficient substrate and a buffer layer enabled of a ferroelectric thin-film waveguide modulator with 40-Gb/s operation.
Structural, magnetic and electrical properties of ferromagnetic/ferroelectric multilayers
Authors: Sirena M. , Kaul E. , Pedreros M. B. , Rodriguez C. A. , Guimpel J. , Steren L. B.
Published: June 2011

The La0.75Sr0.25MnO3 (LSMO)/Ba0.7Sr0.3TiO3 (BSTO) superlattices and bilayers, where LSMO is ferromagnetic and BSTO is ferroelectric, were grown by dc sputtering. X-ray diffraction indicates that the samples present a textured growth with the c axis perpendicular to the substrate. Magnetization measurements show a decrease of the sample’s magnetization for decreasing ferromagnetic thickness. This effect could be related to the presence of biaxial strain and a magnetic dead layer in the samples. Conductive atomic force microscopy indicates that the samples present a total covering of the ferromagnetic layer for a ferroelectric thickness higher than four unit cells. Transport tunneling of the carriers seems to be the preferred conduction mechanism through the ferroelectric layer. These are promising results for the development of multiferroic tunnel junctions.
Propagation of three-dimensional electron-acoustic solitary waves
Authors: Shalaby M. , El-Labany S. K. , Sabry R. , El-Sherif L. S.
Published: June 2011

Theoretical investigation is carried out for understanding the properties of three-dimensional electron-acoustic waves propagating in magnetized plasma whose constituents are cold magnetized electron fluid, hot electrons obeying nonthermal distribution, and stationary ions. For this purpose, the hydrodynamic equations for the cold magnetized electron fluid, nonthermal electron density distribution, and the Poisson equation are used to derive the corresponding nonlinear evolution equation, Zkharov–Kuznetsov (ZK) equation, in the small- but finite- amplitude regime. The ZK equation is solved analytically and it is found that it supports both solitary and blow-up solutions. It is found that rarefactive electron-acoustic solitary waves strongly depend on the density and temperature ratios of the hot-to-cold electron species as well as the nonthermal electron parameter. Furthermore, there is a critical value for the nonthermal electron parameter, which decides whether the electron-acoustic solitary wave’s amplitude is decreased or increased by changing various plasma parameters. Importantly, the change of the propagation angles leads to miss the balance between the nonlinearity and dispersion; hence, the localized pulses convert to explosive/blow-up pulses. The relevance of this study to the nonlinear electron-acoustic structures in the dayside auroral zone in the light of Viking satellite observations is discussed.
Chemically fashioned ZnO nanowalls and their potential application for potentiometric cholesterol biosensor
Authors: Israr M. Q. , Sadaf J. R. , Nur O. , Willander M. , Salman S. , Danielsson B.
Published: June 2011

Chemically fashioned zinc oxide (ZnO) nanowalls on aluminum wire have been characterized and utilized to fabricate a potentiometric cholesterol biosensor by an electrostatic conjugation with cholesterol oxidase. The sensitivity, specificity, reusability, and stability of the conjugated surface of ZnO nanowalls with thickness of ∼80 nm have been investigated over a wide logarithmic concentrations of cholesterol electrolyte solution ranging from 1×10−6–1×10−3 M. The presented biosensor illustrates good linear sensitivity slope curve (∼53 mV/decade) corresponding to cholesterol concentrations along with rapid output response time of ∼5 s.
High-throughput characterization of stresses in thin film materials libraries using Si cantilever array wafers and digital holographic microscopy
Authors: Lai Y. W. , Hamann S. , Ehmann M. , Ludwig A.
Published: June 2011

We report the development of an advanced high-throughput stress characterization method for thin film materials libraries sputter-deposited on micro-machined cantilever arrays consisting of around 1500 cantilevers on 4-inch silicon-on-insulator wafers. A low-cost custom-designed digital holographic microscope (DHM) is employed to simultaneously monitor the thin film thickness, the surface topography and the curvature of each of the cantilevers before and after deposition. The variation in stress state across the thin film materials library is then calculated by Stoney's equation based on the obtained radii of curvature of the cantilevers and film thicknesses. DHM with nanometer-scale out-of-plane resolution allows stress measurements in a wide range, at least from several MPa to several GPa. By using an automatic x-y translation stage, the local stresses within a 4-inch materials library are mapped with high accuracy within 10 min. The speed of measurement is greatly improved compared with the prior laser scanning approach that needs more than an hour of measuring time. A high-throughput stress measurement of an as-deposited Fe-Pd-W materials library was evaluated for demonstration. The fast characterization method is expected to accelerate the development of (functional) thin films, e.g., (magnetic) shape memory materials, whose functionality is greatly stress dependent.
High-pressure and high-temperature x-ray diffraction cell for combined pressure, composition, and temperature measurements of hydrides
Authors: Mauron Ph. , Bielmann M. , Remhof A. , Züttel A.
Published: June 2011

We present the design and construction of a high-pressure (200 bars) and high-temperature (600 °C) x-ray diffraction (XRD) cell for the in situ investigation of the hydrogen sorption of hydrides. In combination with a pressure, composition, and temperature system, simultaneous XRD and volumetric measurements become accessible. The cell consists of an x-ray semi-transparent hemispherical beryllium (Be) dome covering a heatable sample stage, which simultaneously allows sample temperatures of up to 600 °C in an applied hydrogen atmosphere of up to 200 bars. The system volume is as low as possible to maximize the precision of the volumetric measurements. Due to the high thermal conductivity of hydrogen, and in order to preserve the mechanical stability of the beryllium, the cell is water cooled. Its operability was studied on the example of the hydrogen absorption of Mg2Ni. The advantages and limitations of the proposed design are discussed.
Spatial filter based 3D resolution improvement and polarization properties of multiphoton multiple-excitation-spot-optical microscopy
Authors: Dilipkumar Shilpa , Diaspro Alberto , Mondal Partha Pratim
Published: June 2011

Three-dimensional (3D) resolution improvement in multi-photon multiple-excitation-spot-optical microscopy is proposed. Specially designed spatial filter is employed for improving the overall 3D resolution of the imaging system. An improvement up to a factor of 14.5 and sub-femto liter volume excitation is achieved. The system shows substantial sidelobe reduction (<4%) due to the non-linear intensity dependence of multiphoton process. Polarization effect on x-oriented and freely rotating dipoles shows dramatic change in the field distribution at the focal-plane. The resulting point-spread function has the ability to produce several strongly localized polarization dependent field patterns which may find applications in optical engineering and bioimaging.
Spin-glasslike behavior of magnetic ordered state originating from strong interparticle magnetostatic interaction in α-Fe nanoparticle agglomerate
Authors: Hiroi Kosuke , Kura Hiroaki , Ogawa Tomoyuki , Takahashi Migaku , Sato Tetsuya
Published: June 2011

In strongly interacting nanoparticle agglomerate through dipolar coupling, prepared using chemically synthesized α-Fe nanoparticle, the temperature Tpeak at which the zero-field-cooled magnetization exhibits its peak reaches 385 K. This indicates that the magnetic ordering appears above room temperature. Aging phenomena and memory effect observed below Tpeak are intrinsically same as that of spin glasses. The appearance of spin-glasslike behavior near room temperature should be attributed to the three-dimensional interparticle coupling that is purely magnetostatic.
Polarized light extraction in m-plane GaN light-emitting diodes by embedded photonic-crystals
Authors: Matioli Elison , Brinkley Stuart , Kelchner Kathryn M. , Nakamura Shuji , DenBaars Steven , Speck James , Weisbuch Claude
Published: June 2011

The polarization-preserving property of photonic crystals (PhCs) is combined to the superior extraction efficiency of embedded PhCs to enhance polarized light emission in m-plane GaN light-emitting diodes. As guided modes in m-plane GaN are mostly polarized along the a-direction (E⃗∥a⃗), their efficient extraction is achieved by one-dimensional embedded PhCs also aligned to the a-direction. A better diffraction efficiency is obtained by air-gap PhCs which required the growth of high quality, defect-free, m-plane GaN coalesced over the embedded air-grooves.
Photoelectron imaging spectroscopy of nitroethane anions
Authors: Adams Christopher L. , Weber J. Mathias
Published: June 2011

We present low-energy velocity map photoelectron imaging results for bare and Ar solvated nitroethane anions. We report an improved value for the adiabatic electron affinity of nitroethane of (191 ± 6) meV which is used to obtain a C-NO2 bond dissociation energy of (0.589 ± 0.019) eV in nitroethane anion. We assign a weak feature at (27 ± 5) meV electron binding energy to the dipole-bound anion state of nitroethane. Photoelectron angular distributions exhibit increasing anisotropy with increasing kinetic energies. The main contributions to the photoelectron spectrum of nitroethane anion can be assigned to the vibrational modes of the nitro group. Transitions involving torsional motion around the CN bond axis lead to strong spectral congestion. Interpretation of the photoelectron spectrum is assisted by ab initio calculations and Franck-Condon simulations.
Heparan sulfate 6-O-sulfotransferase 1
, a gene involved in extracellular sugar modifications, is mutated in patients with idiopathic hypogonadotrophic hypogonadism
Authors: Tornberg Janne , Sykiotis Gerasimos P. , Keefe Kimberly , Plummer Lacey , Hoang Xuan , Hall Janet E. , Quinton Richard , Seminara Stephanie B. , Hughes Virginia , Van Vliet Guy , Van Uum Stan , Crowley William F. , Habuchi Hiroko , Kimata Koji , Pitteloud Nelly , Bülow Hannes E.
Published: June 2011

Neuronal development is the result of a multitude of neural migrations, which require extensive cell-cell communication. These processes are modulated by extracellular matrix components, such as heparan sulfate (HS) polysaccharides. HS is molecularly complex as a result of nonrandom modifications of the sugar moieties, including sulfations in specific positions. We report here mutations in
HS 6-O-sulfotransferase 1
(
HS6ST1
) in families with idiopathic hypogonadotropic hypogonadism (IHH). IHH manifests as incomplete or absent puberty and infertility as a result of defects in gonadotropin-releasing hormone neuron development or function. IHH-associated
HS6ST1
mutations display reduced activity in vitro and in vivo, suggesting that
HS6ST1
and the complex modifications of extracellular sugars are critical for normal development in humans. Genetic experiments in
Caenorhabditis elegans
reveal that HS cell-specifically regulates neural branching in vivo in concert with other IHH-associated genes, including
kal-1
, the FGF receptor, and
FGF
. These findings are consistent with a model in which KAL1 can act as a modulatory coligand with FGF to activate the FGF receptor in an HS-dependent manner.
Natural time analysis of critical phenomena
Authors: Varotsos Panayiotis , Sarlis Nicholas V. , Skordas Efthimios S. , Uyeda Seiya , Kamogawa Masashi
Published: June 2011

A quantity exists by which one can identify the approach of a dynamical system to the state of criticality, which is hard to identify otherwise. This quantity is the variance

of natural time
χ
, where

and
p

k

is the normalized energy released during the
k
th event of which the natural time is defined as
χ

k

 = 
k
/
N
and
N
stands for the total number of events. Then we show that
κ
1
becomes equal to 0.070 at the critical state for a variety of dynamical systems. This holds for criticality models such as 2D Ising and the Bak–Tang–Wiesenfeld sandpile, which is the standard example of self-organized criticality. This condition of
κ
1
 = 0.070 holds for experimental results of critical phenomena such as growth of rice piles, seismic electric signals, and the subsequent seismicity before the associated main shock.
Plasma steam reforming of E85 for hydrogen rich gas production
Authors: Zhu Xinli , Hoang Trung , Lobban Lance L , Mallinson Richard G
Published: June 2011

E85 (85 vol% ethanol and 15 vol% gasoline) is a partly renewable fuel that is increasing in supply availability. Hydrogen production from E85 for fuel cell or internal combustion engine applications is a potential method for reducing CO2 emissions. Steam reforming of E85 using a nonthermal plasma (pulse corona discharge) reactor has been exploited at low temperature (200–300 °C) without external heating, diluent gas, oxidant or catalyst in this work. Several operational parameters, including the discharge current, E85 concentration and feed flow rate, have been investigated. The results show that hydrogen rich gases (63–67% H2 and 22–29% CO, with small amounts of CO2, C2 hydrocarbons and CH4) can be produced by this method. A comparison with ethanol reforming and gasoline reforming under identical conditions has also been made and the behaviour of E85 reforming is found to be close to that of ethanol reforming with slightly higher C2 hydrocarbons yields.
Chemical intermediate detection following corona discharge on volatile organic compounds: general method using molecular beam techniques
Authors: He Luning , Sulkes Mark
Published: June 2011

Nonthermal plasma (NTP)-based treatments of volatile organic compounds (VOCs) have potential for effective environmental remediation. Theory and experiment that consider the basic science pertaining to discharge events have helped improve NTP remediation outcomes. If direct information on early post-discharge chemical intermediates were also available, it would likely lead to additional improvement in NTP remediation outcomes. To this point, however, experiments yielding direct information on post-NTP VOC intermediates have been limited. An approach using supersonic expansion molecular beam methods offers general promise for detection of post-discharge VOC intermediates. To illustrate the potential utility of these methods, we present mass spectra showing the growth of early products formed when pulsed corona discharges were carried out on toluene in He and then in He with added O2. Good general detection of neutral post-discharge species was obtained using 800 nm 150 fs photoionization pulses.
Modelling of plasma response to resonant magnetic perturbation fields in MAST and ITER
Authors: Liu Yueqiang , Kirk A. , Gribov Y. , Gryaznevich M.P. , Hender T.C. , Nardon E.
Published: June 2011

The resonant magnetic perturbation (RMP) fields, including the plasma response, are computed within a linear, full toroidal, single-fluid resistive magnetohydrodynamic (MHD) model, and under realistic plasma conditions for MAST and ITER. The response field is found to be considerably reduced, compared with the vacuum field produced by the magnetic perturbation coils. This field reduction relies strongly on the screening effect from the toroidal plasma rotation. Computations also quantify three-dimensional (3D) distortions of the plasma surface, caused by RMP fields. A correlation is found between the computed mode structures, the plasma surface displacement and the observed density pump-out effect in MAST experiments. Generally, the density pump-out tends to occur when the surface displacement peaks near the X-points.
The LysR-type PcaQ protein regulates expression of a protocatechuate-inducible ABC-type transport system in Sinorhizobium meliloti
Authors: MacLean Allyson M. , Haerty Wilfried , Golding G. Brian , Finan Turlough M.
Published: June 2011

The LysR protein PcaQ regulates the expression of genes encoding products relevant to the degradation of the aromatic acid protocatechuate (3,4-dihydroxybenzoate), and we have previously defined a PcaQ DNA-binding site located upstream of the targetpcaDCHGBoperon inSinorhizobium meliloti. In this work, we show that PcaQ also regulates the expression of theS. meliloti smb20568-smb20787-smb20786-smb20785-smb20784gene cluster, which is predicted to encode an ABC transport system. ABC transport systems have not been shown before to transport protocatechuate, and we have designated this gene clusterpcaMNVWX. The transcriptional start site ofpcaMwas mapped, and the predicted PcaQ DNA-binding site was located at −73 to −58 relative to this site. Results from electrophoretic mobility shift assays with purified PcaQ and from expression assays indicated that PcaQ activates expression of the transport system in the presence of protocatechuate. To investigate this transport system further, we generated apcaMdeletion mutant (predicted to encode the substrate-binding protein) and introduced a polar insertion mutation intopcaN, a gene that is predicted to encode a permease. These mutants grew poorly on protocatechuate, presumably because they fail to transport protocatechuate. Genome analyses revealed PcaQ-like DNA-binding sites encoded upstream of ABC transport systems in other members of the α-proteobacteria, and thus it appears likely that these systems are involved in the uptake of protocatechuate.
Stock culture heterogeneity rather than new mutational variation complicates short-term cell physiology studies of Escherichia coli K-12 MG1655 in continuous culture
Authors: Nahku Ranno , Peebo Karl , Valgepea Kaspar , Barrick Jeffrey E. , Adamberg Kaarel , Vilu Raivo
Published: June 2011

Nutrient-limited continuous cultures in chemostats have been used to study microbial cell physiology for over 60 years. Genome instability and genetic heterogeneity are possible uncontrolled factors in continuous cultivation experiments. We investigated these issues by using high-throughput (HT) DNA sequencing to characterize samples from different phases of a glucose-limited accelerostat (A-stat) experiment withEscherichia coliK-12 MG1655 and a duration regularly used in cell physiology studies (20 generations of continuous cultivation). Seven consensus mutations from the reference sequence and five subpopulations characterized by different mutations were detected in the HT-sequenced samples. This genetic heterogeneity was confirmed to result from the stock culture by Sanger sequencing. All the subpopulations in which allele frequencies increased (betA,cspG/cspH,glyA) during the experiment were also present at the end of replicate A-stats, indicating that no new subpopulations emerged during our experiments. The fact that ~31 % of the cells in our initial cultures obtained directly from a culture stock centre were mutants raises concerns that even if cultivations are started from single colonies, there is a significant chance of picking a mutant clone with an altered phenotype. Our results show that current HT DNA sequencing technology allows accurate subpopulation analysis and demonstrates that a glucose-limitedE. coliK-12 MG1655 A-stat experiment with a duration of tens of generations is suitable for studying cell physiology and collecting quantitative data for metabolic modelling without interference from new mutations.
Effect of supplementing Rhodes grass hay (Chloris gayana) with Berchemia discolor or Zizyphus mucronata on the performance of growing goats in Kenya
Authors: Osuga I. M. , Abdulrazak S. A. , Muleke C. I. , Fujihara T.
Published: June 2011

Twenty growing Small East African goats were used to determine the effects of feeding sun‐dried leaves of the browse forages Berchemia discolor and Zizyphus mucronata as supplements to low‐quality basal diet, Rhodes grass (Chloris gayana) hay, on voluntary feed intake (VFI), digestibility and growth performance. The grass hay and maize bran were used as a control. The dried leaves were then included at the rates of 15% and 30% of the dry matter intake (DMI). Berchemia discolor had the highest crude protein (CP) content of 195.5 g/kg DM, while Z. mucronata had CP content of 169.5 g/kg DM. The grass hay had the lowest CP content of 50.9 g/kg DM. The browse forages had low fibre content [Neutral detergent fibre (NDF); 257.9–369.5 g/kg DM], while the grass hay had high fibre content (NDF; 713.1 g/kg DM). Goats in the groups supplemented with either of the browse forages had higher total DMI, nitrogen (N) intake and retention and live‐weight gains than those in the control diet group. The digestibility of DM and organic matter (OM) was not affected by supplementation, but the CP digestibility increased with supplementation. The use of the browse forages as supplements for goats fed on poor‐quality basal diets would enhance the performance of the animals.
Practical Tips for Sexual Counseling and Psychotherapy in Premature Ejaculation
Authors: Rowland David , Cooper Stewart
Published: June 2011

Introduction

A number of milestones in the treatment of premature ejaculation (PE) have occurred over the past five decades, including the development of various behavioral and cognitive techniques as well as pharmacotherapies that modify neurophysiological processes involved in ejaculation. Nevertheless, the notion that sexual responses such as PE are influenced by physiological, psychobehavioral, cultural, and relationship factors is as valid now as it was 50 years ago, and therefore, interventions should consider all such domains in the development of effective treatment strategies.

Aim

Provide an overview of which patients with PE are suitable to receive psychosexual treatment and the psychological approaches for managing this disorder.

Methods

Review of the literature.

Main Outcome Measure

Psychosexual treatments that integrate behavioral, psychological, and relationship functioning.

Results

PE is typically a couple's problem and, therefore, psychotherapy is best when the partner is involved. Before embarking on psychotherapy, the clinician should obtain a medical history pertaining to sexual-, psychological-, and relationship-related factors, so that the treatment strategy can be tailored to the needs of the individual. General strategies underpinning integrative, “process-oriented” elements of psychotherapy most relevant to PE are: developing the therapist–patient relationship; expressing empathy, genuineness, and positive regard; motivational interviewing, i.e., developing motivation to change; developing discrepancy; working through resistance; identifying PE-related affect, cognitions, and behaviors (including interaction with partners); and supporting self-efficacy. The four main domains that encompass psychotherapy techniques specific to the treatment of PE are: behavioral; cognitive; affective; and relational. Sustained positive outcomes in PE may be obtained using a combination treatment strategy that addresses all elements of PE, including psychological and biological factors.

Conclusions

Psychosexual treatments may help the patient with PE and his partner to address their sexual problems and improve their overall relationship. The effects of psychosexual therapy may be augmented by combining this intervention with pharmacotherapy.
Clinical features and risk factors of extrahepatic seeding after percutaneous radiofrequency ablation for hepatocellular carcinoma
Authors: Shirai Kiyokazu , Tamai Hideyuki , Shingaki Naoki , Mori Yoshiyuki , Moribata Kosaku , Enomoto Shotaro , Deguchi Hisanobu , Ueda Kazuki , Maekita Takao , Inoue Izumi , Iguchi Mikitaka , Yanaoka Kimihiko , Oka Masashi , Ichinose Masao
Published: June 2011

Aim:  To clarify the clinical features of and risk factors for extrahepatic seeding, a major complication following radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC).

Methods:  Our prospective database of 351 nodules in 257 patients with HCC who had undergone RFA between April 2001 and April 2008 was reviewed. The following variables were assessed to identify the risk factors for extrahepatic seeding: age, sex, viral markers, Child–Pugh class, tumor size, number of tumors, RFA indication (tumor size ≤3 cm, number of tumors ≤3), tumor biopsy prior to RFA, degree of histological differentiation, tumor markers, tumor location, number of sessions, and combined transcatheter arterial chemoembolization.

Results:  The median follow‐up period was 36.5 months, during which the rate of seeding after was 5.1% and the 5‐year cumulative seeding rate was 8.4%. The survival rate after neoplastic seeding was 21% at 5 years. Univariate analysis of the risk factors for neoplastic seeding showed significant differences in tumor size, RFA indication, subcapsular lesion, number of sessions, tumor biopsy prior to RFA, and des‐gamma‐carboxy prothrombin value. However, multivariate analysis showed that the only independent risk factor was RFA indication.

Conclusions:  The prognosis of patients with neoplastic seeding was poor. In particular, RFA performed for HCC not satisfying the RFA indication showed a high risk of seeding, and careful consideration should be given to the optimal treatment method and avoiding direct puncture of subcapsular tumors.
Simplified Thermal Model of a Stacked Ball Grid Array Package
Authors: Colombo Luigi P. M. , Petrushin Alexey , Paleari Davide
Published: June 2011

Simplified integrated approaches to thermal modeling of electronics packages call for fast and easy thermal models. However, this is often in contrast with the complexity of the thermal problem to be solved, which prevents the application of simplified approaches. After a review of the available modeling strategies, steady state thermal analysis of a typical stacked ball grid array package based on a thermal resistance network is presented. The physical model is discussed in detail, together with its advantages and limitations. The results have been compared with detailed 3D-simulations performed by means of a commercial code: for thermal design purposes, the accuracy is satisfactorily, leading a prediction error of the junction temperature lower than 10%.
Application of Synchrotron Radiation X-Ray Microtomography to Nondestructive Evaluation of Thermal Fatigue Process in Flip Chip Interconnects
Authors: Tsuritani Hiroyuki , Sayama Toshihiko , Okamoto Yoshiyuki , Takayanagi Takeshi , Uesugi Kentaro , Mori Takao
Published: June 2011

New nondestructive inspection methods with high spatial resolution are expected to support the evaluation and enhancement of the reliability of microjoints on printed circuit boards. An X-ray microtomography system, the SP-μCT has been developed at the Super Photon ring-8 GeV (SPring-8), the largest synchrotron radiation facility in Japan. In this work, the SP-μCT was first applied to the nondestructive evaluation of thermal fatigue phenomena, namely microstructure evolution (i.e., phase growth) and microcrack propagation, appearing in actual solder microbumps of flip chip interconnects due to thermal cyclic loading. In addition, a refraction-contrast imaging technique was simultaneously applied to visualize the fatigue cracks with an actual opening of less than 100 nm. The observed specimen has a flip chip structure joined by Sn-37wt%Pb eutectic solder bumps 150 μm in diameter. Consequently, the process of phase growth and crack propagation was determined via observation of consecutive computed tomography (CT) images obtained in the same plane of the same specimen. As the thermal cycle proceeded, remarkable phase growth was clearly observed, followed by the appearance of fatigue cracks in the corners of the interfaces between the solder bump and Cu pad. Moreover, the CT images also enabled us to evaluate the fatigue lifetime of the bumps, as follows. The lifetime to fatigue crack initiation was estimated by quantifying the increase in the phase growth. The crack propagation lifetime to failure was then determined by measuring the average crack propagation rate. Such results have not been obtainable at all by X-ray CT systems for industrial use and demonstrate the possibility of nondestructive inspection by a synchrotron radiation X-ray microtomography system.
Comparison of methods to determine bandgaps of ultrathin HfO2 films using spectroscopic ellipsometry
Authors: Di Ming , Bersch Eric , Diebold Alain C. , Consiglio Steven , Clark Robert D. , Leusink Gert J. , Kaack Torsten
Published: June 2011

With the replacement of SiO2 by high-k Hf-based dielectrics in complementary metal–oxide–semiconductor technology, the measurement of the high-k oxide bandgap is a high priority. Spectroscopic ellipsometry (SE) is one of the methods to measure the bandgap, but it is prone to ambiguity because there are several methods that can be used to extract a bandgap value. This paper describes seven methods of determining the bandgap of HfO2 using SE. Five of these methods are based on direct data inversion (point-by-point fitting) combined with a linear extrapolation, while two of the methods involve a dispersion model-based bandgap extraction. The authors performed all of these methods on a single set of data from a 40 Å HfO2 film, as well as on data from 20 and 30 Å HfO2 films. It was observed that the bandgap values for the 40 Å film vary by 0.69 eV. In comparing these methods, the reasons for this variation are discussed. The authors also observed that, for each of these methods, there was a trend of increasing bandgap with decreasing film thickness, which is attributed to quantum confinement. Finally, the authors observed a greater variation in bandgap values among the methods for the 40 Å films than among the methods for the 30 and 20 Å films. This is attributed to the larger tail in the extinction coefficient k curve for the 40 Å film.
Precision vacuum pumping speed measurement using sonic nozzles
Authors: Cheung Wan-Sup , Shin Jin-Hyun , Park Kyung-Am , Lim Jong-Yeon
Published: June 2011

Constant volume flow meter systems were developed for measuring pumping speeds of dry vacuum pumps. Their capability to measure throughput in the low vacuum region was exploited to calibrate 0.03, 0.2, and 1.6 mm throat diameter sonic nozzles. It was demonstrated that the calibrated sonic nozzles enabled the precise measurement of the pumping speed of a dry vacuum pump under test as the constant volume flow meter systems. To examine the measurement capability of both approaches considered in this study, the expanded measurement uncertainty, as well as the detailed measurement uncertainty budget, is presented. The proposed pumping speed measurement method has potential application for a new “in situ and portable” pumping speed tester or analyzer for the Korean semiconductor and flat display process industry.
The Mosaic of Surface Charge in Contact Electrification
Authors: Baytekin H. T. , Patashinski A. Z. , Branicki M. , Baytekin B. , Soh S. , Grzybowski B. A.
Published: June 2011

Electrification caused by rubbing two objects creates patches of positive and negative charge on both surfaces.
Organization of Intracellular Reactions with Rationally Designed RNA Assemblies
Authors: Delebecque Camille J. , Lindner Ariel B. , Silver Pamela A. , Aldaye Faisal A.
Published: June 2011

Multidimensional RNA structures can act as scaffolds for the spatial organization of bacterial metabolism.
Targeted Genome Editing Across Species Using ZFNs and TALENs
Authors: Wood Andrew J. , Lo Te-Wen , Zeitler Bryan , Pickle Catherine S. , Ralston Edward J. , Lee Andrew H. , Amora Rainier , Miller Jeffrey C. , Leung Elo , Meng Xiangdong , Zhang Lei , Rebar Edward J. , Gregory Philip D. , Urnov Fyodor D. , Meyer Barbara J.
Published: June 2011

Engineered nucleases target specific DNA sequences for gene disruption in nonmodel organisms.
Paradoxical embolus to the brain from embolization of a carotid body tumor: Figure 1
Authors: Gemmete Joseph J , Pandey Aditya S , Chaudhary Neeraj , Potti Thomas A
Published: June 2011

A patent foramen ovale (PFO) is a common heart defect in the general population. Paradoxical embolization of material through a PFO has been an identified cause of stroke. Taking measures to recognize a PFO in a patient undergoing intra-arterial particulate embolization is necessary in order to reduce the risk of stroke secondary to paradoxical embolism. We present a case of paradoxical stroke in a patient with a highly vascular head and neck tumor and an asymptomatic PFO.
Synthesis of gold nanocubes in aqueous solution with remarkable shape-selectivity
Authors: Miranda Adelaide , Malheiro Eliana , Eaton Peter , Carvalho Patrícia A. , de Castro Baltazar , Pereira Eulália
Published: June 2011

This paper reports a facile method to prepare gold nanocubes with an average size length of 13 ± 2 nm, a shape selectivity >90%, and a very good reproducibility. The gold nanocubes were prepared by photocatalytic reduction of Au(III) using a cationic, water soluble porphyrin as the photocatalyst, and cetyltrimethylammonium bromide as the capping agent. The synthesis is performed in water, at pH 7, and room temperature. The nanocubes were characterized by transmission electron microscopy, scanning electron microscopy, atomic force microscopy, and X-ray phototelectron spectroscopy. Shape selectivity for the synthesis of nanocubes is due to a different rate of growth of the (100) and (111) facets of the nanoparticles, and such control in this synthesis is achieved by careful selection of the initial gold precursor for the photocatalytic cycle.
Mechanisms underlying distension-evoked peristalsis in guinea pig distal colon: is there a role for enterochromaffin cells?
Authors: Spencer Nick J. , Nicholas Sarah J. , Robinson Lucy , Kyloh Melinda , Flack Nicholas , Brookes Simon J. , Zagorodnyuk Vladimir P. , Keating Damien J.
Published: June 2011

The mechanisms underlying distension-evoked peristalsis in the colon are incompletely understood. It is well known that, following colonic distension, 5-hydroxytryptamine (5-HT) is released from enterochromaffin (EC) cells in the intestinal mucosa. It is also known that exogenous 5-HT can stimulate peristalsis. These observations have led some investigators to propose that endogenous 5-HT release from EC cells might be involved in the initiation of colonic peristalsis, following distension. However, because no direct evidence exists to support this hypothesis, the aim of this study was to determine directly whether release of 5-HT from EC cells was required for distension-evoked colonic peristalsis. Real-time amperometric recordings of 5-HT release and video imaging of colonic wall movements were performed on isolated segments of guinea pig distal colon, during distension-evoked peristalsis. Amperometric recordings revealed basal and transient release of 5-HT from EC cells before and during the initiation of peristalsis, respectively. However, removal of mucosa (and submucosal plexus) abolished 5-HT release but did not inhibit the initiation of peristalsis nor prevent the propagation of fecal pellets or intraluminal fluid. Maintained colonic distension by fecal pellets induced repetitive peristaltic waves, whose intrinsic frequency was also unaffected by removal of the submucosal plexus and mucosa, although their propagation velocities were slower. In conclusion, the mechanoreceptors and sensory neurons activated by radial distension to initiate peristalsis lie in the myenteric plexus and/or muscularis externa, and their activation does not require the submucosal plexus, release of 5-HT from EC cells, nor the presence of the mucosa. The propagation of peristalsis and propulsion of liquid or solid content along the colon is entrained by activity within the myenteric plexus and/or muscularis externa and does not require sensory feedback from the mucosa, nor neural inputs arising from submucosal ganglia.
Activated AMPK inhibits PPAR-α and PPAR-γ transcriptional activity in hepatoma cells
Authors: Sozio Margaret S. , Lu Changyue , Zeng Yan , Liangpunsakul Suthat , Crabb David W.
Published: June 2011

AMP-activated protein kinase (AMPK) and peroxisome proliferator-activated receptor-α (PPAR-α) are critical regulators of short-term and long-term fatty acid oxidation, respectively. We examined whether the activities of these molecules were coordinately regulated. H4IIEC3 cells were transfected with PPAR-α and PPAR-γ expression plasmids and a peroxisome-proliferator-response element (PPRE) luciferase reporter plasmid. The cells were treated with PPAR agonists (WY-14,643 and rosiglitazone), AMPK activators 5-aminoimidazole-4-carboxamide riboside (AICAR) and metformin, and the AMPK inhibitor compound C. Both AICAR and metformin decreased basal and WY-14,643-stimulated PPAR-α activity; compound C increased agonist-stimulated reporter activity and partially reversed the effect of the AMPK activators. Similar effects on PPAR-γ were seen, with both AICAR and metformin inhibiting PPRE reporter activity. Compound C increased basal PPAR-γ activity and rosiglitazone-stimulated activity. In contrast, retinoic acid receptor-α (RAR-α), another nuclear receptor that dimerizes with retinoid X receptor (RXR), was largely unaffected by the AMPK activators. Compound C modestly increased AM580 (an RAR agonist)-stimulated activity. The AMPK activators did not affect PPAR-α binding to DNA, and there was no consistent correlation between effects of the AMPK activators and inhibitor on PPAR and the nuclear localization of AMPK-α subunits. Expression of either a constitutively active or dominant negative AMPK-α inhibited basal and WY-14,643-stimulated PPAR-α activity and basal and rosiglitazone-stimulated PPAR-γ activity. We concluded that the AMPK activators AICAR and metformin inhibited transcriptional activities of PPAR-α and PPAR-γ, whereas inhibition of AMPK with compound C activated both PPARs. The effects of AMPK do not appear to be mediated through effects on RXR or on PPAR/RXR binding to DNA. These effects are independent of kinase activity and instead appear to rely on the activated conformation of AMPK. AMPK inhibition of PPAR-α and -γ may allow for short-term processes to increase energy generation before the cells devote resources to increasing their capacity for fatty acid oxidation.