bluuebunny/crossref_metadata_2025 huggingface dataset:
Flip-Chip Packaging of Low-Noise Metamorphic High Electron Mobility Transistors on Low-Cost Organic Substrate
Authors: Wang Chin-Te , Kuo Chien-I , Hsu Heng-Tung , Chang Edward Yi , Hsu Li-Han , Lim Wee-Chin , Miyamoto Yasuyuki
Published: September 2011

The rapid growth of high-frequency wireless communication demands high-performance packaging structures at low cost. A flip-chip interconnect is one of the most promising technologies owing to its low parasitic effect and high performance at high frequencies. In this study, the in-house fabricated In0.6Ga0.4As metamorphic high electron mobility transistor (mHEMT) device was flip-chip-assembled using a commercially available low-cost organic substrate. The packaged device with the optimal flip-chip structure exhibited almost similar DC and RF results to the bare die. An exopy-based underfill was applied to the improvement of reliability with almost no degradation of the electrical characteristics. Measurement results revealed that the proposed packaging structure maintained a low minimum noise figure of 3 dB with 6 dB associated gain at 62 GHz. Such a superior performance after flip-chip packaging demonstrates the feasibility of the proposed low-cost organic substrate for commercial high-frequency applications up to the W-band.
Non-contact Deformable Mirror Actuator for Spherical Aberration Compensation
Authors: Hashizume Jiro , Ide Tatsuro , Kanamaru Masatoshi , Mukoh Masaki , Watanabe Koichi , Yamauchi Yoshiaki
Published: September 2011

We have proposed and demonstrated a novel non-contact electromagnetic deformable mirror actuator for spherical aberration compensation with simple configurations. The magnetic ring with low stiffness placed on a mirror deformed the mirror into an ideal parabolic shape by applying a magnetic force generated from an electromagnet underneath. We were able to control the deformation of the mirror by adjusting the applied voltage. The maximum deviation from ideal shape was less than 30 nm. In addition, a continuous change of the defocus aberration proportional to the 1.5-λRMS/µm deformation of the mirror was achieved.
Thermal Analysis of Heat-Assisted Magnetic Recording Optical Head with Laser Diode on Slider
Authors: Xu Baoxi , Chia Cheow Wee , Zhang Qide , Toh Yeow Teck , An Chengwu , Vienne Guillaume
Published: September 2011

For the optical head used in heat-assisted magnetic recording (HAMR), mounting a laser diode chip on the slider offers a more integrated, compact, and stable design. However, the heat generated by the laser diode will cause the head temperature to increase, which may decrease the laser output power and change the slider flying status. In this paper, the thermal analysis of the HAMR head including the laser diode and a transducer is conducted. The effects of the laser diode power, the power absorbed by the transducer, boundary thermal resistance between the laser diode chip and the slider substrate, and slider fly speed and fly height on the laser temperature increase, the transducer temperature increase, and the air-bearing surface temperature distribution are studied. The deformation of the air-bearing surface caused by its temperature change is also analyzed.
Simple Readout Channel Model of Super-Resolution Near-Field Structure Disk System
Authors: Tanabe Takaya , Igawa Hiroki , Suzuki Keisuke , Ansai Tsutomu
Published: September 2011

The readout channel response of super-resolution near-field structure (super-RENS) disks have been experimentally investigated using a 63-bit pseudorandom sequence and the autocorrelation of the readout sequence. The time domain analysis reveals that the super-RENS disk has two responses: one is the response of the normal readout beam and the other is the sharp differentiated response of the super-RENS effect. The numerical analysis proves that the sharp differentiated response offers an excellent spatial resolution of the super-RENS disks.
Ultra High Density Scanning Electrical Probe Phase-Change Memory for Archival Storage
Authors: Wang Lei , Wright C. David , Shah Purav , Aziz Mustafa M. , Sebastian Abu , Pozidis Haralampos , Pauza Andrew
Published: September 2011

The potential for using probe-based phase-change memories for the future archival storage at densities of around 1 Tbit/in.2 is investigated using a recording medium comprising a Si/TiN/DLC/GeSbTe/diamond-like carbon (DLC) stack together with a conductive PtSi tip for writing and reading. Both experimental and computational simulation results are presented. The simulations include a physically-realistic threshold switching model, as well as the effects of thermal boundary resistance and electrical contact resistance. The simulated bit size and shape correspond closely to that written experimentally.
Multiresolution Coding Using Amplitude and Phase Modulations for Holographic Data Storage
Authors: Hiramatsu Ryosuke , Shigaki Masanobu , Nitta Kouichi , Matoba Osamu
Published: September 2011

A new data coding method using both amplitude and phase modulations is proposed for increasing the coding rate in a holographic memory. The phase modulation code has a lower resolution than the conventional sparse block code used as the amplitude modulation code. The phase modulation code can add more than 1 bit to the amplitude modulation code. We show that the coding rate can be increased up to 0.78 from 0.67 in the 3:9 amplitude modulation code when the binary phase code is added. We also show that the bit error rate and signal-to-noise ratio in the amplitude data are improved by adding the phase modulation code in speckle shift multiplexing. The histogram of the phase distribution is also separated well.
Volumetric Optical Recording with Void Marks Using an All-Semiconductor Picosecond Laser
Authors: Tashiro Shiori , Yamatsu Hisayuki , Takemoto Yoshihiro , Fujita Goro , Miura Takahiro , Iwamura Takashi , Uchiyama Hiroshi , Yun KyungSung
Published: September 2011

We demonstrated volumetric optical recording with void marks in a bulk recording medium using a newly developed all-semiconductor picosecond laser. The laser is compact and has an ultrahigh peak power, which is necessary for practical application of the volumetric optical recording system. We confirmed the laser to be able to record void marks effectively on our recording media. The laser was implemented to our optical drive system as a light source and as much as 30 layer void-mark recording was carried out on the 200-µm-thick bulk recording medium. The total recording capacity was 97 Gbyte and the bit error rates (bERs) were measured to be on the order of 10-4 for most of the layers. We believe that this was a significant step to realize a practical volumetric optical recording system.
One-Head Near-Field Writing/Erasing on a Rewritable Dual-Layer Optical Disk Having High-Index Cover and Separation Layers
Authors: Narumi Kenji , Hisada Kazuya , Mihara Takashi , Habuta Haruhiko , Hayashi Katsuhiko , Tanaka Yasuhiro , Sano Kousei , Tomita Hironori , Shiono Teruhiro , Furumiya Shigeru , Kojima Rie , Birukawa Masahiro , Yamada Noboru
Published: September 2011

Near-field writing and erasing on a rewritable dual-layer optical disk with a single solid immersion lens (SIL) optical head is demonstrated for the first time. A novel beam expander enabled access to both information layers of the disk without exchanging two individual optical heads. A rewritable dual-layer disk having high-index (n=1.8) cover and separation layers was newly developed. By using the SIL optical system and the disk, an effective numerical aperture (NA) of 1.42 is achieved and a recording capacity of 180 Gbyte for the dual-layer rewritable disk is expected.
Multilayer Thin-Film Capacitor Fabricated by Radio-Frequency Magnetron Sputtering
Authors: Imamiya Yuji , Kanno Isaku , Yokokawa Ryuji , Kotera Hidetoshi
Published: September 2011

In this study, we fabricate multilayer ceramic capacitors (MLCCs) composed of dielectric layers with Pt internal electrodes by single sputtering deposition. We deposited approximately 300-nm-thick BaTiO3 (BT) layers on Pt/Ti-coated SiO2/Si substrates through a movable shadow mask. The separated internal Pt electrodes are prepared by sliding the shadow mask. Multilayered BT thin films are uniformly deposited on a Si substrate with external electrodes on both sides of the BT films. The MLCCs with five BT layers have excellent dielectric properties; a relative dielectric constant of approximately 320 and a dielectric loss of around 2% regardless of the number of dielectric layers.
Crystal Orientation Control of Bismuth Layer-Structured Dielectric Films Using Interface Layers of Perovskite-Type Oxides
Authors: Kondoh Yohta , Sasajima Keiichi , Hayashi Mari , Kimura Junichi , Takuwa Itaru , Ehara Yoshitaka , Funakubo Hiroshi , Uchida Hiroshi
Published: September 2011

Thin films of SrBi4Ti4O15, a kind of bismuth layer-structured dielectrics (BLSDs), were prepared on platinized silicon wafers buffered by perovskite-type oxide interface layers, (100)LaNiO3/(111)Pt/TiO2/(100)Si and (001)Ca2Nb3O10-nanosheets/(111)Pt/TiO2/(100)Si, by chemical solution deposition (CSD). The Ca2Nb3O10nanosheets were supported on a (111)Pt/TiO2/(100)Si substrate by dip coating using an aqueous dispersion, while (100)LaNiO3was prepared by CSD. The (00l) planes of BLSD crystal were preferentially oriented on the surface of both substrates, which is caused by suitable lattice matching between thea-(b-)axis of BLSD and perovskite-type oxide layers. The film deposition on (001)Ca2Nb3O10nanosheets yielded (001)-oriented BLSD films with higher crystallinity and smaller fluctuation in the tilting angle of the (001)BLSD plane than those on the (100)LaNiO3interface layer. The dielectric constant (εr) of (001)-oriented SrBi4Ti4O15film on (001)Ca2Nb3O10-nanosheets/(111)Pt/TiO2/(100)Si substrate was approximately 190, which was significantly stable against the change of frequency and bias voltage compared with that of the randomly-oriented SrBi4Ti4O15film.
Preparation of BiFeO3 Thin Films on SrRuO3/SrTiO3(001) Substrate by Dual Ion Beam Sputtering
Authors: Nakashima Seiji , Fujisawa Hironori , Suminaga Hiroyuki , Park Jung Min , Nishioka Hiroshi , Kobune Masafumi , Kanashima Takeshi , Okuyama Masanori , Shimizu Masaru
Published: September 2011

BiFeO3 (BFO) thin films with various Bi/Fe ratios have been deposited on SrRuO3/SrTiO3(001) substrates by dual ion beam sputtering. A Bi2O3 ceramic disk and an α-Fe2O3 powder disk were used as targets, and simultaneously sputtered using a dual ion beam. Bi/Fe ratio has been controlled by adjusting the beam current ratio on the Bi2O3- and α-Fe2O3-side ion sources. Even a BFO thin film with a Bi/Fe ratio of 0.95 and a smooth surface shows a slightly leaky characteristic. [Fe2+]/([Fe3+]+[Fe2+]) ratio has been estimated by Auger electron spectroscopy (AES). From the AES profiles, the [Fe2+]/([Fe3+]+[Fe2+]) ratio of the BFO thin film with a Bi/Fe ratio of 0.95 is estimated to be 0.14. It is considered that not only improving surface roughness but also enhancing oxidization is important for reduction in leakage current.
Changes in Ferroelectric Domain Structure with Electric Fatigue in Li0.06(Na0.5K0.5)0.94NbO3 Ceramics
Authors: Tsurekawa Sadahiro , Hatao Hiroki , Takahashi Hirofumi , Morizono Yasuhiro
Published: September 2011

Piezoelectric materials should have stable performance during electric cycling in service. Because piezoelectricity-related properties depend on the ferroelectric domain structure, it is essential to investigate the fatigue characteristics of domain structures under electric loading. Piezoresponse force microscopy (PFM) was used to observe changes in ferroelectric domain structure with cyclic electric loading in MnO2-doped Li0.06(Na0.5K0.5)0.94NbO3 (LNKN) ceramics. The PFM observations revealed that polarization loss occurred owing to electric fatigue, and that domain width and length fraction of 180° domain walls increased with increasing number of cycles. The decreases in the piezoelectric constant d
33 and the electromechanical coupling coefficient k
p observed owing to electric fatigue are compared with fatigue of the domain structure.
Modes of Domain Wall Motion and Polarization of Lead Zirconate Titanate Polycrystals
Authors: Omori Minoru , Mishima Tsuneo , Fujimoto Tetsuro
Published: September 2011

Domain wall motion depending on polarization field has been studied for tetragonal lead zirconate titanate (PZT) polycrystals. The domain structure of PZT polycrystals was observed in a backscattered electron image obtained with a scanning electron microscope under various poling conditions. Domain wall reorientation was observed when the applied polarization field strength became higher than the coercive electric field. An in situ X-ray diffraction (XRD) measurement was also done to evaluate the domain wall motion contribution, under a polarization field. The XRD intensity ratio of (002) vs (200) reached as much as 0.72, which was explained by taking the both contributions of domain wall reorientation and translation. The experimental data and consideration by a geometrical domain wall motion model confirmed that the domain wall translation has zero threshold energy and the domain wall reorientation occurs beyond the coercive electric strength, corresponding to a finite threshold energy.
Preparation of Barium Titanate–Potassium Niobate Nanostructured Ceramics with Artificial Morphotropic Phase Boundary Structure By Solvothermal Method
Authors: Wada Satoshi , Shimizu Shigehito , Yamashita Kenta , Fujii Ichiro , Nakashima Kouichi , Kumada Nobuhiro , Kuroiwa Yoshihiro , Fujikawa Yoshinori , Tanaka Daisuke , Furukawa Masato
Published: September 2011

Barium titanate (BaTiO3, BT)–potassium niobate (KNbO3, KN) (BT–KN) nanostructured ceramics with a distorted interface region, i.e., artificial morphotropic phase boundary (MPB) structure, were prepared by the solvothermal method. The results of the optimization of reaction conditions showed that the metastable region of only KN crystal growth was obtained using a mixture of KOH and K2CO3 as the K source and Nb2O5 as the Nb source in ethanol. Moreover, KN formation under the metastable region using a particle compact composed of a mixture of BT and Nb2O5 particles as substrates resulted in the successful preparation of BT–KN nanostructured ceramics with an artificial MPB region and a porosity of around 35%. This is the first report on the preparation of ceramics with a heteroepitaxial interface between BT and KN below 230 °C.
Growth of Shape-Controlled Ca3NbGa3Si2O14 and Sr3NbGa3Si2O14 Single Crystals by Micro-Pulling-Down Method and Their Physical Properties
Authors: Yokota Yuui , Sato Masato , Tota Kazushige , Futami Yoshisuke , Yanagida Takayuki , Onodera Ko , Yoshikawa Akira
Published: September 2011

Shape-controlled langasite-type piezoelectric single crystals, Ca3NbGa3Si2O14 (CNGS) and Sr3NbGa3Si2O14 (SNGS), were grown by the micro-pulling-down (µ-PD) method and their physical properties were investigated. Columnar-shaped CNGS and SNGS crystals with a- and c-axes in the growth direction were grown and the diameters of the grown columnar-shaped crystals were controlled to be approximately 3 mm from the initial to the later part. The grown crystals without cracks indicated relatively high crystallinities and a single phase of the langasite-type structure in the powder X-ray diffraction patterns. Meanwhile, in the outside area of the crystals, parts of second phases were detected and energy dispersive X-ray spectroscopy measurements indicated that the second phases of the CNGS and SNGS crystals were the Ca–Nb–O and Sr–Nb–O systems, respectively. The d
11 of the CNGS crystal indicated 3.98 pC/N, which was coincident with those of previous reports.
Vibration Energy Harvesting Characterization of 1 cm2Poly(vinylidene fluoride) Generators in Vacuum
Authors: Cao Ziping , Zhang Jinya , Kuwano Hiroki
Published: September 2011

In this study, poly(vinylidene fluoride) (PVDF) was used as a piezoelectric element to fabricate small size (two-dimensional area <1 cm2) generators with low resonant frequency (about 100 Hz) for matching the frequency of vibration sources. To clarify the effect of the air damping on the vibration energy harvesting, PVDF generators were investigated in three measurement conditions: “unpackaged in air”, “packaged in air”, and “unpackaged in vacuum”. It was found that the output power of generators “unpackaged in vacuum” was almost twice that of generators “packaged in air” at 0.5gacceleration. With the increase in vibration acceleration, the output power of generators “unpackaged in vacuum” rapidly increased in a quadratic relationship with the acceleration at low acceleration level, and then the increasing ratio decreased at high acceleration. At 4.31gacceleration, the output power reached 100.833 µW.
High Power DC–DC Conversion Applications of Disk-Type Radial Mode Pb(Zr,Ti)O3 Ceramic Transducer
Authors: Moon Sol , Park Joung-Hu
Published: September 2011

In this paper, a new application of magnetic-less high-power DC–DC switching converter with an Pb(Zr,Ti)O3 Ceramic transducer is described. For the full elimination of magnetic devices from the high power application, this paper presents a resonant-type step-down DC–DC power converter employing a disk-type piezoelectric transducer, along with the demonstration of the design process and the hardware-experiment results. For validation of the feasibility, a 10 W output DC–DC power converter hardware was implemented. The experimental result shows an excellent output control capability under switching frequency variation with a high power-efficiency greater than 95%. The thermal distribution image of the transducer under the high power operation was also measured. The result shows that the transducer has very stable thermal operation even under the full load condition.
Resonant Inelastic X-ray Scattering at Ba-L3 Edge in BaTiO3
Authors: Yoshii Kenji , Jarrige Ignace , Matsumura Daiju , Nishihata Yasuo , Suzuki Chikashi , Ito Yoshiaki , Mukoyama Takeshi , Tochio Tatsunori , Shinotsuka Hiroshi , Fukushima Sei
Published: September 2011

Resonant inelastic X-ray scattering (RIXS) measurements have been carried out at the Ba-L3 absorption edge on ferroelectric BaTiO3 for the first time. The absorption spectrum was measured in the partial fluorescence yield mode, by monitoring the intensity of the maximum of the Ba-Lα1 line through the Ba-L3 edge. The main peak, which reflects the unoccupied density of Ba 5d states, is found to be narrow, although broad shoulderlike tails appear towards both low and high energies. Using band structure calculations, these tails are ascribed to the strong hybridization between unoccupied Ba 5d and O 2p bands. Hybridization notwithstanding, the Ba 5d band is shown to retain a localized character, on the basis of the incident energy dependence of the Ba-Lα1 RIXS spectra.
Crystal Growth and Characterization of (Bi0.5Na0.5)TiO3–BaTiO3 Single Crystals Obtained by a Top-Seeded Solution Growth Method under High-Pressure Oxygen Atmosphere
Authors: Onozuka Hiroaki , Kitanaka Yuuki , Noguchi Yuji , Miyayama Masaru
Published: September 2011

A single crystal of ferroelectric 0.88(Bi,Na)TiO3–0.12BaTiO3 (BNT–BT) solid solution with tetragonal P4m
m structure was grown by a top-seeded solution growth (TSSG) method at a high oxygen pressure (P
O2
) of 0.9 MPa. The crystals exhibited a large remanent polarization (P
r) of 54 µC/cm2, which leads to a spontaneous polarization estimated to be 54 µC/cm2. The large P
r compared with that of crystals grown at P
O2
= 0.1 MPa is suggested to originate from a low oxygen vacancy concentration. The high-P
O2
TSSG method is demonstrated to be effective for obtaining large-sized, high-quality BNT–BT crystals.
Nanoscale Characterization of Domain Structures in Bi4Ti3O12Single Crystals Using Near-Field Raman Spectroscopy
Authors: Carmignano Claudia , Osada Minoru , Noguchi Yuji , Kitanaka Yuuki , Miyayama Masaru
Published: September 2011

We have investigated domain structures in Bi4Ti3O12(BiT) single crystals by Raman scattering using scanning near-field optical microscopy (SNOM). In SNOM–Raman spectra, the polarization dependence reflects domain structures, and the spectra at the domain-wall region exhibit the splitting of the TiO6mode at ∼840 cm-1with the appearance of additional peaks, the behavior of which is different from that observed in the single-domain region. From the resonant Raman spectra of highly deficient BiT single crystals, we find that the resonance is localized at oxygen vacancies in TiO6octahedra, and planer defects, owing to oxygen vacancies, accumulate near the domain walls, causing a strong domain pinning.
Millimeter-Wave Dielectric Properties of Cordierite/Indialite Glass Ceramics
Authors: Ohsato Hitoshi , Kim Jeong-Seog , Kim A-Young , Cheon Chae-Il , Chae Ki-Woong
Published: September 2011

Millimeter-wave wireless communications with high data transfer and radar system for Pre-Crash Safety System have been developed recently. Cordierite (Mg2Al4Si5O18) is one of the silicates with good millimeter-wave dielectric properties. Cordierite has two polymorphs: cordierite and indialite. Cordierite is of low symmetry form with ordered structure, and indialite is of high symmetry form with disordered structure. In this study, indialite/cordierite glass ceramics are fabricated with good millimeter-wave properties. The Qf values are dependent on the amount of indialite phase and crystallization conditions. Indialite with high symmetry showed higher Qf values than cordierite with low symmetry. This result clearly shows that high symmetry results in high Qf when the samples are prepared under the same crystallization conditions. However, these glass ceramics are very difficult to make under the same conditions because of non-uniform crystallization. These dielectric glass ceramics show high Qf values of >200,000 GHz, low dielectric constant εr = 4.7, and TCf= -27 ppm/°C.
Sympathetic and cardiovascular responses to venous distension in an occluded limb
Authors: Cui Jian , Leuenberger Urs A. , Gao Zhaohui , Sinoway Lawrence I.
Published: September 2011

We recently showed that a fixed volume (i.e., 40 ml) of saline infused into the venous circulation of an arterially occluded vascular bed increases muscle sympathetic nerve activity (MSNA) and blood pressure. In the present report, we hypothesized that the volume and rate of infusion would influence the magnitude of the sympathetic response. Blood pressure, heart rate, and MSNA were assessed in 13 young healthy subjects during forearm saline infusions (arrested circulation). The effects of different volumes of saline (i.e., 2%, 3%, 4%, or 5% forearm volume at 30 ml/min) and different rates of infusion (i.e., 5% forearm volume at 10, 20, or 30 ml/min) were evaluated. MSNA and blood pressure responses were linked with the infusion volume. Infusion of 5% of forearm volume evoked greater MSNA responses than did infusion of 2% of forearm volume (Δ11.6 ± 1.9 vs. Δ3.1 ± 1.8 bursts/min and Δ332 ± 105 vs. Δ38 ± 32 units/min, all P < 0.05). Moreover, greater MSNA responses were evoked by saline infusion at 30 ml/min than 10 ml/min ( P < 0.05). Sonographic measurements confirmed that the saline infusions induced forearm venous distension. The results suggest that volume and rate of saline infusion are important factors in evoking sympathetic activation. We postulate that venous distension contributes to cardiovascular autonomic adjustment in humans.
A novel vascular EET synthase: role of CYP2C7
Authors: Sun Dong , Jiang Houli , Wu Hongyan , Yang YangMing , Kaley Gabor , Huang An
Published: September 2011

We demonstrated previously that cytochrome P-450 (CYP) 2C29 is the epoxyeicosatrienoic acid (EET) synthase responsible for the EET-mediated flow/shear stress-induced dilation of vessels of female nitric oxide (NO)-deficient mice (Sun D, Yang YM, Jiang H, Wu H, Ojami C, Kaley G, Huang A. Am J Physiol Regul Integr Comp Physiol 298: R862–R869, 2010). In the present study, we aimed to identify which specific CYP isoform(s) is the source of the synthesis and release of EETs in response to stimulation by shear stress in vessels of rats. Cannulated mesenteric arteries isolated from both sexes of NG-nitro-l-arginine methyl ester (l-NAME)-treated rats were perfused with 2 and 10 dyn/cm2 shear stress, followed by collection of the perfusate to determine EET concentrations and isoforms. Shear stress stimulated release of EETs in the perfusate of female (but not male) NO-deficient vessels, associated with an EET-mediated vasodilation, in which 11,12- and 14,15-EET contributed predominantly to the responses. Rat CYP cDNA array screened a total of 32 CYP genes of mesenteric arteries, indicating a significant upregulation of CYP2C7 in female l-NAME-treated rats. Endothelial RNA and protein were extracted from intact single vessels. Expression of CYP2C7 mRNA and protein in pooled extractions of endothelial lysate was identified by PCR and Western blot analyses. Transfection of the vessels with CYP2C7 short interfering RNA eliminated the release of EETs, consequently abolishing the EET-mediated flow-induced dilation; these responses, however, were maintained in vessels transfected with nonsilencing short interfering RNA. Knockdown of endothelial CYP2C7 was confirmed by PCR and Western blot analyses. In conclusion, CYP2C7 is an endothelial EET synthase in the female rat vasculature, by which, in NO deficiency, shear stress stimulates the release of EETs to initiate vasodilation.
Mitochondrial superoxide and coenzyme Q in insulin-deficient rats: increased electron leak
Authors: Herlein Judith A. , Fink Brian D. , Henry Dorlyne M. , Yorek Mark A. , Teesch Lynn M. , Sivitz William I.
Published: September 2011

Mitochondrial superoxide is important in the pathogeneses of diabetes and its complications. However, there is uncertainty regarding the intrinsic propensity of mitochondria to generate this radical. Studies to date suggest that superoxide production by mitochondria of insulin-sensitive target tissues of insulin-deficient rodents is reduced or unchanged. Moreover, little is known of the role of the Coenzyme Q (CoQ), whose semiquinone form reacts with molecular oxygen to generate superoxide. We measured reactive oxygen species (ROS) production, respiratory parameters, and CoQ content in mitochondria from gastrocnemius muscle of control and streptozotocin (STZ)-diabetic rats. CoQ content did not differ between mitochondria isolated from vehicle- or STZ-treated animals. CoQ also was unaffected by weight loss in the absence of diabetes (induced by caloric restriction). Under state 4 or state 3 conditions, both respiration and ROS release were reduced in diabetic mitochondria fueled with succinate, glutamate plus malate, or with all three substrates (continuous TCA cycle). However, H2O2 and directly measured superoxide production were substantially increased in gastrocnemius mitochondria of diabetic rats when expressed per unit oxygen consumed. On the basis of substrate and inhibitor effects, the mechanism involved multiple electron transport sites. More limited results using heart mitochondria were similar. ROS per unit respiration was greater in muscle mitochondria from diabetic compared with control rats during state 3, as well as state 4, while the reduction in ROS per unit respiration on transition to state 3 was less for diabetic mitochondria. In summary, ROS production is, in fact, increased in mitochondria from insulin-deficient muscle when considered relative to electron transport. This is evident on multiple energy substrates and in different respiratory states. CoQ is not reduced in diabetic mitochondria or with weight loss due to food restriction. The implications of these findings are discussed.
The 2′,3′-cAMP-adenosine pathway
Authors: Jackson Edwin K.
Published: September 2011

Our recent studies employing HPLC-tandem mass spectrometry to analyze venous perfusate from isolated, perfused kidneys demonstrate that intact kidneys produce and release into the extracellular compartment 2′,3′-cAMP, a positional isomer of the second messenger 3′,5′-cAMP. To our knowledge, this represents the first detection of 2′,3′-cAMP in any cell/tissue/organ/organism. Nuclear magnetic resonance experiments with isolated RNases and experiments in isolated, perfused kidneys suggest that 2′,3′-cAMP likely arises from RNase-mediated transphosphorylation of mRNA. Both in vitro and in vivo kidney experiments demonstrate that extracellular 2′,3′-cAMP is efficiently metabolized to 2′-AMP and 3′-AMP, both of which can be further metabolized to adenosine. This sequence of reactions is called the 2′,3′-cAMP-adenosine pathway (2′,3′-cAMP → 2′-AMP/3′-AMP → adenosine). Experiments in rat and mouse kidneys show that metabolic poisons increase extracellular levels of 2′,3′-cAMP, 2′-AMP, 3′-AMP, and adenosine; however, little is known regarding the pharmacology of 2′,3′-cAMP, 2′-AMP, and 3′-AMP. What is known is that 2′,3′-cAMP facilitates activation of mitochondrial permeability transition pores, a process that can lead to apoptosis and necrosis, and inhibits proliferation of vascular smooth muscle cells and glomerular mesangial cells. In summary, there is mounting evidence that at least some types of cellular injury, by triggering mRNA degradation, engage the 2′,3′-cAMP-adenosine pathway, and therefore this pathway should be added to the list of biochemical pathways that produce adenosine. Although speculative, it is possible that the 2′,3′-cAMP-adenosine pathway may protect against some forms of acute organ injury, for example acute kidney injury, by both removing an intracellular toxin (2′,3′-cAMP) and increasing an extracellular renoprotectant (adenosine).
The epithelial sodium/proton exchanger, NHE3, is necessary for renal and intestinal calcium (re)absorption
Authors: Pan Wanling , Borovac Jelena , Spicer Zachary , Hoenderop Joost G. , Bindels René J. , Shull Gary E. , Doschak Michael R. , Cordat Emmanuelle , Alexander R. Todd
Published: September 2011

Passive paracellular proximal tubular (PT) and intestinal calcium (Ca2+) fluxes have been linked to active sodium (re)absorption. Although the epithelial sodium/proton exchanger, NHE3, mediates apical sodium entry at both these sites, its role in Ca2+homeostasis remains unclear. We, therefore, set out to determine whether NHE3 is necessary for Ca2+(re)absorption from these epithelia by comparing Ca2+handling between wild-type and NHE3−/−mice. Serum Ca2+and plasma parathyroid hormone levels were not different between groups. However, NHE3−/−mice had increased serum 1,25-dihydroxyvitamin D3. The fractional excretion of Ca2+was also elevated in NHE3−/−mice. Paracellular Ca2+flux across confluent monolayers of a PT cell culture model was increased by an osmotic gradient equivalent to that generated by NHE3 across the PT in vivo and by overexpression of NHE3.45Ca2+uptake after oral gavage and flux studies in Ussing chambers across duodenum of wild-type and NHE3−/−mice confirmed decreased Ca2+absorption in NHE3−/−mice compared with wild-type mice. Consistent with this, intestinal calbindin-D9K, claudin-2, and claudin-15 mRNA expression was decreased. Microcomputed tomography analysis revealed a perturbation in bone mineralization. NHE3−/−mice had both decreased cortical bone mineral density and trabecular bone mass. Our results demonstrate significant alterations of Ca2+homeostasis in NHE3−/−mice and provide a molecular link between Na+and Ca2+(re)absorption.
Effect of cold air inhalation and isometric exercise on coronary blood flow and myocardial function in humans
Authors: Muller Matthew D. , Gao Zhaohui , Drew Rachel C. , Herr Michael D. , Leuenberger Urs A. , Sinoway Lawrence I.
Published: September 2011

The effects of cold air inhalation and isometric exercise on coronary blood flow are currently unknown, despite the fact that both cold air and acute exertion trigger angina in clinical populations. In this study, we used transthoracic Doppler echocardiography to measure coronary blood flow velocity (CBV; left anterior descending coronary artery) and myocardial function during cold air inhalation and handgrip exercise. Ten young healthy subjects underwent the following protocols: 5 min of inhaling cold air (cold air protocol), 5 min of inhaling thermoneutral air (sham protocol), 2 min of isometric handgrip at 30% of maximal voluntary contraction (grip protocol), and 5 min of isometric handgrip at 30% maximal voluntary contraction while breathing cold air (cold + grip protocol). Heart rate, blood pressure, inspired air temperature, CBV, myocardial function (tissue Doppler imaging), O2 saturation, and pulmonary function were measured. The rate-pressure product (RPP) was used as an index of myocardial O2 demand, whereas CBV was used as an index of myocardial O2 supply. Compared with the sham protocol, the cold air protocol caused a significantly higher RPP, but there was a significant reduction in CBV. The cold + grip protocol caused a significantly greater increase in RPP compared with the grip protocol ( P = 0.045), but the increase in CBV was significantly less ( P = 0.039). However, myocardial function was not impaired during the cold + grip protocol relative to the grip protocol alone. Collectively, these data indicate that there is a supply-demand mismatch in the coronary vascular bed when cold ambient air is breathed during acute exertion but myocardial function is preserved, suggesting an adequate redistribution of blood flow.
Rapid Determination of Total Thujone in Absinthe Using 1H NMR Spectroscopy
Authors: Monakhova Yulia B. , Kuballa Thomas , Lachenmeier Dirk W.
Published: September 2011

1H NMR spectroscopy is utilized to quantify total thujone (sum of α‐ and β‐isomers) in absinthe. For sample preparation, a simple dilution with buffer is required. Thujone produces a distinct peak of the CH2 group in the cyclopentanone moiety in the 2.13–2.11 ppm range. No overlap with other typical constituents such as anethole or fenchone occurs. The detection limit of 0.3 mg/L is adequate to control the EU maximum limit. The relative standard deviation was 6%, and linearity was observed from 1 to 100 mg/L. Applicability was proven by analysis of 69 authentic absinthes. The correlation between NMR and our previous method consisting of liquid‐liquid extraction followed by GC/MS was significant (P < 0.0001, R = 0.93). The simple and cheap NMR method can be used for rapid screening of absinthes for total thujone content while chromatographic techniques are recommended for more specific (α‐ and β‐thujone isomers) analysis if required.
Role of Stress Myocardial Scintigraphy in the Evaluation of Incompletely Revascularized Post-PCI Patients
Authors: Galassi Alfredo R. , Marzá Francesco , Azzarelli Salvatore , Tomasello Salvatore D.
Published: September 2011

Percutaneous coronary intervention (PCI) is actually the most used method of revascularization. Although complete revascularization remains a desirable goal, it may not be possible or not easy to plan in many patients. Thus, incomplete revascularization might be a preferred treatment strategy in selected patient categories. Stress myocardial scintigraphy, because of its high diagnostic accuracy and prognostic value and its ability to assess location and extent of myocardial ischemia regardless of symptoms as well as to evaluate patients who are unable to exercise or who have uninterpretable electrocardiogram, is of paramount importance for clinical decision making in patients with multivessel disease and incomplete revascularization.
Mucosal Immunity andCandida albicansInfection
Authors: Moyes David L. , Naglik Julian R.
Published: September 2011

Interactions between mucosal surfaces and microbial microbiota are key to host defense, health, and disease. These surfaces are exposed to high numbers of microbes and must be capable of distinguishing between those that are beneficial or avirulent and those that will invade and cause disease. Our understanding of the mechanisms involved in these discriminatory processes has recently begun to expand as new studies bring to light the importance of epithelial cells and novel immune cell subsets such as Th17 T cells in these processes. Elucidating how these mechanisms function will improve our understanding of many diverse diseases and improve our ability to treat patients suffering from these conditions. In our voyage to discover these mechanisms, mucosal interactions with opportunistic commensal organisms such as the fungusCandida albicansprovide insights that are invaluable. Here, we review current knowledge of the interactions betweenC. albicansand epithelial surfaces and how this may shape our understanding of microbial-mucosal interactions.
Biliobronchial Fistula after Liver Surgery for Giant Hydatid Cyst
Authors: Loinaz Carmelo , Hernández Teresa , Mitjavila Mercedes , Martín Jaime , Ochando Federico , Madariaga Maria Lucia , Fernández Beatriz , Hernández Pilar , Rueda José , Ramos María , Jiménez Pedro , Vorwald Peter , Fernández José María , Quintáns Antonio
Published: September 2011

Background.
Biliobronchial fistula (BBF) is a rare
complication in the natural history of liver
hydatid disease by Echinococcus
granulosus. We present a case of BBF
after resection of a giant liver hydatid cyst in
a 72-year-old woman. Case
Report. A total cystpericystectomy was
done, leaving the left lateral section of the
liver that was fixed to the diaphragm.
Postoperatively, the patient developed
obstructive jaundice. An ERCP showed an
obstruction at the junction of the left biliary
duct and the main biliary duct and contrast
leak. At reoperation, the main duct was ischemic,
likely due to torsion along its longitudinal
axis. A hepatotomy was done at the hilar plate,
and the biliary duct was dissected and
anastomosed to a Roux-en-Y jejunal loop. She was
discharged without complications. Five months
later, the patient developed cholangitis and was
successfully treated with antibiotics. However,
she suffered repeated respiratory infections, and
four months later she was admitted to the
hospital with fever, cough, bilioptysis, and
right lower lobe pneumonia. The diagnosis of BBF
was confirmed with Mebrofenin
scintigraphy. At transhepatic cholangiography,
bile duct dilation was seen, with a
biliothoracic leak. She underwent dilatation
of cholangiojejunostomy stricture with
placement of an external-internal catheter. The
catheter was removed 3.5 months later, and two
years later the patient remains in very good
condition. Conclusion. An
indirect treatment of the BBF by percutaneous
transhepatic dilation of the biliary stenosis
avoided a more invasive treatment, with
satisfactory outcome.
Synthesis, Antimicrobial, and Anticoagulant Activities of 2-(Arylsulfonyl)indane-1,3-diones
Authors: Jeyachandran Malaichamy , Ramesh Penugonda
Published: September 2011

2-(Arylsulfonyl)indane-1,3-diones, earlier synthesized by Claisen condensation involving diethyl phthalate and aryl methyl sulphones, are found to be potent blood anticoagulants. In search of improved analogs of 2-(arylsulfonyl)indane-1,3-dione, we have synthesized them (7 a-f) by a different route involving Knoevenagel reaction between phthalic anhydride and arylsulfonylacetates in the presence of pyridine-piperidine medium for the first time. The synthesized 2-(arylsulfonyl)indane-1,3-diones were evaluated for antimicrobial and anticoagulant activities and all of them registered significant activity.
A Case of Montelukast-Induced Churg-Strauss Syndrome Associated with Liver Dysfunction
Authors: Matsui Keiji , Nishijima Kosuke
Published: September 2011

A 64-year-old woman was admitted to hospital due to protracted diarrhea and liver dysfunction. The patient was diagnosed as Churg-Strauss syndrome (CSS) due to asthma, paranasal sinusitis, hypereosinophilia, and polyneuropathy. There was a history of taking montelukast, a leukotriene receptor antagonist (LTRA), which is thought to have some relationship with CSS. The liver biopsy specimen showed eosinophilic infiltration and centrolobular fatty change. In this paper, we review the relationship between LTRA and CSS. Several lines of evidence suggest that leukotriene plays an important role in maintaining neural tissues. We also review the potential relationship between centrolobular fatty change and pivoxil-containing antibiotics, which was prescribed for sinusitis before admission. Carnitine deficiency induced by pivoxil-containing agents may cause impaired fatty acid oxidation in mitochondria.
On a Class of Nonautonomous Max‐Type Difference Equations
Authors: Liu Wanping , Yang Xiaofan , Stević Stevo
Published: September 2011

This paper addresses the max‐type difference equation , n ∈ ℕ0, where k, m ∈ ℕ, B > 0, and is a positive sequence with a finite limit. We prove that every positive
solution to the equation converges to under some conditions. Explicit positive solutions to two particular cases are
also presented.
TP53 Mutations and HBX Status Analysis in Hepatocellular Carcinomas from Iran: Evidence for Lack of Association between HBV Genotype D and TP53 R249S Mutations
Authors: Abedi-Ardekani Behnoush , Gouas Doriane , Villar Stephanie , Sotoudeh Masoud , Hainaut Pierre
Published: September 2011

High incidence of HCC is mostly due to the combination of two major risk factors, chronic infection with hepatitis B (HBV) and/or C (HCV) viruses and exposure to the mycotoxin aflatoxin B1, which induces a particular mutation at codon 249 in TP53 (R249S). Eight genotypes of HBV are diversely found in high and low incidence areas. Regardless of documented strong associations between TP53 R249S mutation and HBV genotypes B, C, A or E, there is no report of such association for genotype D despite of the presence of aflatoxin in areas with high prevalence of HBV genotype D. In Iran, 3% of the population is chronically infected with HBV, predominantly genotype D. Twenty-one histologically confirmed HCC cases from Iran were analyzed for TP53 R249S and HBV double mutations 1762T/1764A, hallmarks of more pathogenic forms of HBV. We did not detect any of these mutations. In addition, we report the only case identified so far carrying both R249S mutation and chronic HBV genotype D, a patient from The Gambia in West Africa. This paper suggests that association between HBV genotype D and aflatoxin-induced TP53 mutation is uncommon, explaining the relatively lower incidence of HCC in areas where genotype D is highly prevalent.
Atypical Clinical and Diagnostic Features in Ménétrier's Disease in a Child
Authors: Chung Michael , Pittenger Jaime , Flomenhoft Deborah , Bennett Jeffrey , Lee Eun-Young , Shashidhar Harohalli
Published: September 2011

Ménétrier's disease is one of the rarest protein-losing gastropathies in childhood. It is characterized clinically by non-specific gastrointestinal symptoms and edema, biochemically by hypoalbuminemia, and pathologically by enlarged gastric folds. In adults, this disease can be devastating with significant morbidity and mortality. In childhood, it is a self-limiting, transient and benign illness. Its treatment is largely supportive with total parenteral nutrition (TPN) while oral intake is encouraged. Acute onset of vomiting in healthy school age children can be initially explained by acute viral gastroenteritis. However, persistent vomiting associated with hematemesis and severe abdominal pain should warrant further work-up. This case report illustrates a self-limiting and rare cause of protein-losing enteropathy called Ménétrier's disease that presented with several variant clinical features not typically described in association with this entity.
Intima Sarcoma of the Pulmonary Artery Mimicking Takayasu Disease
Authors: Belge C. , Renckens I. , Van Puijenbroek R. , Wuyts W. , Meyns B. , Delcroix M.
Published: September 2011

Pulmonary artery intima sarcoma is an uncommon but fatal tumor, which often masquerades chronic thromboembolic pulmonary hypertension (CTEPH) and in the present case Takayasu arteritis. Pulmonary arterial pressure is mildly elevated in the presence of extensive proximal lesions. A parenchyma thin-walled cavitary lesion may be a sign of pulmonary extravasation of the tumor.
Liver Regeneration and Aging: A Current Perspective
Authors: Schmucker Douglas L. , Sanchez Henry
Published: September 2011

Many organ systems exhibit significant age-related deficits, but, based on studies in old rodents and elderly humans, the liver appears to be relatively protected from such changes. A remarkable feature of the liver is its capacity to regenerate its mass following partial hepatectomy. Reports suggests that aging compromises the liver's regenerative capacity, both in the rate and to the extent the organ's original volume is restored. There has been modest definitive information as to which cellular and molecular mechanisms regulating hepatic regeneration are affected by aging. Changes in hepatic sensitivity to growth factors, for example, epidermal growth factor (EGF), appear to influence regeneration in old animals. Studies have demonstrated (a) a 60% decline in EGF binding to hepatocyte plasma membranes, (b) reduced expression of the hepatic high affinity EGF receptor and (c) a block between G1 and S-phases of the cell cycle in old rats following EGF stimulation. Recent studies suggest that reduced phosphorylation and dimerization of the EGF receptor, critical steps in the activation of the extracellular signal-regulated kinase pathway and subsequent cell proliferation are responsible. Other studies have demonstrated that aging affects the upregulation of a Forkhead Box transcription factor, FoxM1B, which is essential for growth hormone-stimulated liver regeneration in hepatectomized mice. Aging appears to compromise liver regeneration by influencing several pathways, the result of which is a reduction in the rate of regeneration, but not in the capacity to restore the organ to its original volume.
A Proteome Reference Map of the Causative Agent of Melioidosis Burkholderia pseudomallei
Authors: Wongtrakoongate Patompon , Roytrakul Sittiruk , Yasothornsrikul Sukkid , Tungpradabkul Sumalee
Published: September 2011

Burkholderia pseudomallei is the etiologic agent of melioidosis. Using 2DE and MALDI‐TOF MS, we report here a proteome reference map constructed from early stationary phase, a bacterial adaptation process. We identified 282 protein spots representing 220 ORFs; many of them have been implicated in bacterial pathogenesis. Up to 20% of identified ORFs belong to post‐translational modification and stress responses. The proteome reference map will support future analysis of the bacterial gene and environmental regulation and facilitate comparative proteomics with its sibling species.
Myometrial Cystic Formation after Local Methotrexate Application into Cornual Gestational Sac: A Case Report of an Unexpected Complication
Authors: Ozkan Zehra Sema , Kumbak Banu , Sapmaz Ekrem , Simsek Mehmet
Published: September 2011

Cornual pregnancy is a rare type of ectopic pregnancy, and diverse therapeutic options exist for the management. Medical treatment despite high initial beta HCG values is not thought to be safe. We reported a 39-year-old woman with an initial beta HCG value of 22000 mIU/mL and diagnosed of a cornual pregnancy. Patient was managed successfully with the administration of combined systemic and ultrasonographically guided local injection of methotrexate into the gestational sac. During followup with serial beta hcg measurements,  mm cystic area in myometrium has been detected. Beta hcg <1 mIU/mL value was reached three months later, and this cystic area resolved spontaneously. Systemic methotrexate administration combined with ultrasound-guided local methotrexate injection into the gestational sac might be considered as the first-line treatment in the management of hemodynamically stable patients having cornual pregnancy even with high beta HCG values and risk of myometrial cystic formation.