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AbstractAn approach for modeling damage in the material in a geometrically nonlinear setting is studied. We consider a gradient-enhanced damage approach where the damage variable is taken as an independent variable, and the fluxes conjugated to the damage gradient are computed. The concept of maximum dissipation is used to derive the global Kuhn–Tucker conditions. The total free energy function consists of two nonlocal terms corresponding to referential gradient of the nonlocal damage variable and a penalty term to bridge the local damage variable and the nonlocal damage variable. Based on the principle of minimum total potential energy, a coupled system of Euler–Lagrange equations is obtained and solved in weak form. These nonlinear system of equations is solved by a standard Newton–Raphson-type solution scheme. The regularization capabilities, as well as the accuracy and efficiency of the proposed damage models are demonstrated by some standard benchmark examples. [ABSTRACT FROM AUTHOR]

We investigated the structures and expansion behavior of double-Shockley stacking faults (DSFs) formed in heavily nitrogen-doped 4H-SiC during annealing. Heavily doped epilayers prepared as specimens were successively annealed. Various types of DSFs showing different shapes and dislocation contrasts were found in photoluminescence and synchrotron X-ray topography images. Taking account of every possible stacking sequence forming DSFs, the structures of various types of DSFs were determined from observations by plan-view transmission electron microscopy (TEM) and cross-sectional high-angle annular dark-field scanning TEM. We found that a bounding dislocation enclosing a DSF splits into two partial dislocations (PDs), and their Burgers vectors are identical, while the distance of the two PDs depended on their core structures (30° Si-, 30° C- or 90° C-core). We also discussed the contrast rule for the dislocation consisting of two PDs in the synchrotron X-ray topography images and the mobile PDs for the DSF expansion in the epilayers with different nitrogen concentrations. [ABSTRACT FROM AUTHOR]

This paper presents equilibrium mechanics and a finite element model for analysing a scissor structure that contains pivots with zero bending stiffness representing structural instability. The pivot at the centre of each structural unit, which is a feature of scissor structures, can be used to transfer the displacement between the units. It cannot, however, transfer the rotation between these units, and the angular stiffness must be considered independently for each unit. To construct a general model of the scissor structure, a scissor unit was developed using the left and right boundary connections of adjacent units to simulate a periodically symmetric structure. The proposed method allows us to obtain an accurate distribution of the internal forces and deflections without the use of special elements to account for central pivots. [ABSTRACT FROM AUTHOR]

The mobility of graphene transferred on a SiO2/Si substrate is limited to ∼10 000 cm2V-1s-1. Without understanding the graphene/SiO2 interaction, it is difficult to improve the electrical transport properties. Although surface structures on SiO2 such as silanol and siloxane groups are recognized, the relation between the surface treatment of SiO2 and graphene characteristics has not yet been elucidated. This paper discusses the electrical transport properties of graphene on specific surface structures of SiO2 prepared by O2-plasma treatments and reoxidization. [ABSTRACT FROM AUTHOR]

• Partial dislocations (PDs) of the stacking faults (SFs) in 4H-SiC were characterized. • The SFs were Shockley type with more Shockley PDs than previously reported. • The number of Shockley PDs and the stacking sequence were focused on. • In addition to those, the PD-introduced basal planes were also focused on. • The three items was correlated and discussed with expansion from previous reports. The microstructure of the partial dislocations was characterized with respect to three types of stacking faults found in our previous work on 4H-SiC epitaxial film on p-type substrates. These stacking faults were found to be Shockley-type with five, six, and nine Shockley-type partial dislocations with Burgers vector directions parallel to the basal planes, which are more than previously reported. The correspondence between the number of Shockley partial dislocations, the stacking sequence, and the basal planes in which partial dislocations are introduced was discussed for the number of partial dislocations up to nine with regard to Shockley-type stacking faults with expansion from previous reports. [ABSTRACT FROM AUTHOR]

SUMMARY: In this paper, we present a novel flexible sensor array manufacturing process that involves transfer printing methods using a chip mounter with a vacuum collet. We successfully transfer‐printed continuously very fragile microelectromechanical systems (MEMS)‐based 5‐mm‐long, 1‐mm‐wide, 5‐μm‐thick high‐aspect‐ratio ultrathin PZT (1.9 μm)/Si (3 μm) strain sensors onto a polyimide based flexible printed‐circuit (FPC) substrate with etched Cu wiring. Then, we connected the sensors to the Cu wiring by printing insulating and conductive pastes using a screen printer. The output voltage based on the deformation behavior of the test plate was generated from the flexible piezoelectric strain sensor array attached to the plate. Therefore, the developed piezoelectric sensor array is capable of easily performing the distribution measurement of the strain leading to damage such as cracks. [ABSTRACT FROM AUTHOR]

Double Shockley-type stacking faults (2SSFs) formed in 4H-SiC epitaxial films with a dopant concentration of 1.0  ×  10 16  cm −3 were characterized using grazing incident X-ray topography and high-resolution scanning transmission electron microscopy. The origins of 2SSFs were investigated, and it was found that 2SSFs in the epitaxial layer originated from narrow SFs with a double Shockley structure in the substrate. Partial dislocations formed between 4H-type and 2SSF were also characterized. The shapes of 2SSFs are related with Burgers vectors and core types of the two Shockley partial dislocations. [ABSTRACT FROM AUTHOR]

Three types of unidentified stacking faults with emission wavelengths of over 500 nm were confirmed in 4H-SiC epitaxial films and characterized using grazing incident X-ray topography, transmission electron microscopy, and high-resolution scanning transmission electron microscopy. Photoluminescence spectroscopy measurements revealed that the SFs had emissions at around 550, 530, and 520 nm. Characterization indicated that the SFs included one Frank partial dislocation and several Shockley partial dislocations, although the determined stacking sequences of the SFs mainly consisted of the basic units of the 3C-structure. It was clarified that the SFs originated from narrow SFs with the same stacking sequence in the substrates. [ABSTRACT FROM AUTHOR]

We theoretically study the spin-polarized current flowing through a Josephson junction (JJ) in a spin injection device. When the spin-polarized current is injected from a ferromagnet in a superconductor (SC), the charge current is carried by the superconducting condensate (Cooper pairs), while the spin-up and spin-down currents flow in equal magnitude but in the opposite direction in a SC, because of no quasiparticle charge current in the SC. This indicates that not only the Josephson current but also the spin current flow across JJ at zero bias voltage, thereby generating Joule heating by the spin current. The result provides a new method for detecting the spin current by measuring Joule heating at JJ. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We report successful fabrication and characteristics of submicron-size tunneling junctions using c-axis YBa[sub 2]Cu[sub 3]O[sub 7-y] (YBCO) thin films of 800 nm thickness and Bi[sub 2]Sr[sub 2]CaCu[sub 2]O[sub 8+δ](Bi-2212) single-crystal whiskers. The junctions were made using a three-dimensional focused-ion-beam etching method. First, a microbridge was patterned in a required junction width by normal direction etching. By tilting the sample stage up to 90°, two grooves on the bridge were etched from the lateral direction in order to create the required junction size. The 60 K YBCO junctions did not show any degradation of critical current density (J[sub c]) down to an in-plane area of 0.5 μm2 and showed current-voltage (I-V) characteristics of the collective switching transition from the zero voltage state to the resistive state. For Bi-2212 stacks smaller than 1 μm2, we identified some of the features of charging effects on the I-V characteristics. &! copy; 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The boundaries between 3C and 4H-SiC domains on the prismatic planes of hexagonal lattices formed in a 4H-SiC epitaxial film were investigated using both transmission and scanning transmission electron microscopy. These observations determined that the boundaries have a periodic structure, in which each unit cell consists of 12 basal planes of the hexagonal lattice. Six Shockley partial dislocations are situated in each unit cell of the boundary structure. Burgers vectors and core structures of these partial dislocations are discussed. [ABSTRACT FROM AUTHOR]

This paper considers tensegrity structures constructed from repetition of simple fundamental units. The tensegrity prism is chosen as a fundamental unit, which allows us to build plates, columns, towers, and their variations. The connectivity matrix plays a central role in analysis and design of tensegrity structures. This paper provides a systematic way to construct connectivity matrices for tensegrity structures constructed from repetition of tensegrity prisms. The number of units and node locations (shape) can be chosen arbitrarily. As an application of the connectivity matrix, a minimal-mass design subjected to force equilibrium (force balance) and yield and buckling stress constraints is shown. [ABSTRACT FROM AUTHOR]

LiSiN crystals are synthesized by direct reaction between LiN and SiN with the molar ratio LiN/SiN of 10:1. Reaction is performed at 1073 K for 1 h under a nitrogen atmosphere of 700 Torr. The lattice constant determined by the X-ray powder diffraction method is 4.718 Å. Four broad Raman peaks are observed at 196, 286, 580, and 750 cm. By analogy with LiMgN, the broad peak at 580 cm with a half width of 140 cm is attributed to homogenously random distribution of Li and Si atoms. The band gap of LiSiN is found to be a direct gap of about 2.5 eV by optical absorption and photoacoustic spectroscopy methods. Comparison with the conventional cathode materials for lithium ion batteries, this gap value is close to d-d transition energy of Mn in LiMnO (1.63 eV or 2.00 eV) and that of Co in LiCoO (2.1 eV), suggesting that LiSiN is a possible cathode material. The 5 × 5 mm-sized lithium secondary battery of LiSiN cathode/propylene carbonate + LiClO electrolyte/Li anode structure shows a discharge capacity of 2.4 μAh cm for a discharge current of 1.0 μA. [ABSTRACT FROM AUTHOR]

Li 7 La 3 (Zr 2 − x Nb x )O 12 (LLZNbO, x = 0–1.5) was prepared using sol–gel process at low temperatures. Additives (LiBO 2 and Li 3 BO 3 ) were used to improve the sintering of the ceramic electrolyte at low temperatures. XRD patterns of the calcined powder displayed the formation of cubic garnet phase between 600 and 700 °C in composition with higher Nb content (LLZNbO, x ≥ 0.5). The density of composites with additives sintered at 900 °C achieves 90%. In composites sintered with LiBO 2 , the presence of La 2 Zr 2 O 7 was detected, whereas single cubic phase was obtained for the composites sintered with Li 3 BO 3 . The ion conductivity attained was 7 × 10 − 5 S/cm at 30 °C using 6.5 wt% Li 3 BO 3 (900 °C), representing enhancement by more than two orders of magnitude compared to the material without additives. Improvements of Li ion conductivity can be interpreted by the enhanced relative density as the result of the rearrangement of particles produced by adequate concentration of the additive. [ABSTRACT FROM AUTHOR]

Triangular defects with a characteristic morphology consisting of a 3C-type structure were investigated on Si-face 4H-SiC epitaxial films using electron microscopy. Two types of triangular defects were investigated: one with a single valley on the surface along the [ 11 2 ¯ 0 ] direction and another with several parallel ridges and valleys called “washboard-like defects”. The defects with a single valley had a characteristic domain structure consisting of four 3C crystals, which is similar to that of previously reported comet-shaped defects on the C-face. It is shown that the 3C domain in the washboard-like defect is covered by 4H layers with a washboard-like morphology. [ABSTRACT FROM AUTHOR]

Magnetoresistivity ρxx and Hall resistivity ρxy in ultrahigh magnetic fields up to 88 T are measured down to 0.15 K to clarify the multiband electronic structure in high-quality single crystals of superconducting FeSe. At low temperatures and high fields we observe quantum oscillations in both resistivity and the Hall effect, confirming the multiband Fermi surface with small volumes. We propose a novel approach to identify from magnetotransport measurements the sign of the charge carriers corresponding to a particular cyclotron orbit in a compensated metal. The observed significant differences in the relative amplitudes of the quantum oscillations between the ρxx and ρxy components, together with the positive sign of the high-field ρxy, reveal that the largest pocket should correspond to the hole band. The low-field magnetotransport data in the normal state suggest that, in addition to one hole and one almost compensated electron band, the orthorhombic phase of FeSe exhibits an additional tiny electron pocket with a high mobility. [ABSTRACT FROM AUTHOR]

BACKGROUND AND PURPOSE: Reperfusion injury after thrombolytic therapy can have adverse neurologic effects. The free-radical scavenger edaravone is used in combination with the recombinant tissue plasminogen activator alteplase to treat acute ischemic stroke. However, basic investigations of this combination use remain inadequate. Here, we used an in vivo model to investigate the effects of edaravone on alteplase-induced thrombolysis. METHODS: Thrombolysis was evaluated by using a He-Ne-laser-induced thrombosis model in rat mesenteric microvessels. Changes in thrombus volume were analyzed with the image analysis software Image-Pro Plus (Media Cybernetics, USA). There were three experimental groups (placebo, alteplase 0.6mg/kg, alteplase 0.6mg/kg+edaravone 10.5mg/kg). Sequential changes (0 to 60min) in thrombus volume were compared by using a relative optical density method that we had used previously. RESULTS: In the placebo group, the thrombus volume at 60min, reflecting the extent of thrombolysis, was 97.2%±5.7% of the initial value. In the alteplase group, thrombus volume decreased to 70.7%±4.1% (P<0.01) after 20min and 14.2%±6.6% after 60min. In the alteplase+edaravone group, thrombus volume decreased to 66.9%±7.2% (P<0.001) after 10min and 10.9%±2.3% after 60min. CONCLUSIONS: These results support the hypothesis that edaravone accelerates thrombolysis by alteplase. [ABSTRACT FROM AUTHOR]

The band gap of and disordered structure in Li8SiN4 (lattice constant: a = 10.148 Å, c = 9.567 Å) are studied by optical absorption, photoacoustic spectroscopy, X-ray diffraction, and Raman scattering spectroscopy. Li8SiN4 is a semiconductor with a band gap of 2.4 eV, suggesting the transition from the N-2p valence band to the conduction band mainly consisting of Si-3s and/or -3p orbitals. A broad Raman peak is observed at 586 cm-1, indicating the homogenously random distribution of Li and Si atoms. Li8SiN4 crystallizes in a superstructure of eight face-centered N sublattices. In each sublattice, one Li and one Si atom are randomly and diagonally occupied at two tetrahedral sites next to N, while six Li atoms reside at the other sites next to N. The possible locations of one remaining Li atom are also discussed. Li8SiN4 is a direct transition, which is slightly larger than the d-d electron transitions in the typical cathode materials LiMn2O4 and LiCoO2. For a 5 × 5 mm2 sized lithium secondary battery with the Li8SiN4 + acetylene black cathode/propylene carbonate + LiClO4 electrolyte/Li anode structure, the capacity for the discharge current of 10 µA is between 2.44 µAh/cm2 and 3.56 µAh/cm2 for a potential range between 2.8 V and 3.8 V. (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

The crystallographic structures of comet-shaped defects observed on the C-face 4H-SiC epitaxial film were investigated using electron microscopy. The comet-shaped defects consist of head and tail parts. The tail part is symmetric with respect to the ( 1 1 ¯ 00 ) plane in the cross-sectional image and narrows along the [ 1 ¯ 1 ¯ 20 ] direction, i.e., along the step-flow direction of epitaxial film growth on the C-face. The tail part consists of four 3C domains with characteristic twin boundaries of Σ3 and Σ27. The head part is formed by 3C and defective hexagonal-SiC polycrystalline grains during epitaxial film growth. [ABSTRACT FROM AUTHOR]

In addition to cognitive impairment, behavioral and psychological symptoms of dementia (BPSD) are another important aspect of most dementia patients. This study was designed for a new simple assessment of BPSD. We first employed a clinical survey for the local community with sending an inquiry letter to all members (n = 129) of dementia caregiver society, and then attempted to create a new BPSD score for dementia with 10 BPSD items. This new simple BPSD score was compared to a standard-detailed BPSD score neuropsychiatric inventory (NPI) for a possible correlation (n = 792) and a time to complete (n = 136). Inter-rater reliability was examined comparing scores between main and second caregivers (n = 70) for AD. Based on the clinical survey for local caregivers, a new BPSD score for dementia (ABS, Abe's BPSD score) was newly created, in which each BPSD item was allotted by an already-weighted score (maximum 1–9) based on the frequency and severity, and was finalized with taking temporal occurrences into account. ABS was filled by the main caregiver with a full score of 44, was well correlated with NPI (r = 0.716, **p < 0.01) in 792 AD patients (age 78.6 ± 7.0 years, MMSE 19.0 ± 5.9), and took a shorter time as only 56.8 ± 38.8 s (**p < 0.01) than NPI score (132.7 ± 94.0 s) with 136 AD patients. A high inter-rater reliability was obtained (r = 0.964, **p < 0.01) with a little smaller score (0.877 time) of ABS in secondary than the main caregivers. ABS provides a new simple and quick test for BPSD assessment, with a good correlation to NPI but a shorter time, and with a high inter-rater reliability. Thus ABS is useful for evaluating BPSD for mild to moderate dementia patients. [ABSTRACT FROM AUTHOR]

Background and purpose Diabetes mellitus ( DM) is associated with a decline in cognitive and affective functions. Methods In all, 182 outpatients with DM were investigated for associations of cognitive and affective functions with diabetes-related factors and cerebral white matter abnormalities. In addition, the difference in cognitive decline of age-matched late elderly normal subjects and DM patients was investigated. Results The present study revealed that cognitive and affective functions declined in some DM patients. Furthermore, the decline in these functions was unrelated to fasting blood sugar level but was related to glycosylated hemoglobin (HbA1c) and insulin resistance. Poor HbA1c control was associated with a significant decline in the 'calculation' subscale and insulin resistance for 'naming', 'read list of letters' and 'delayed recall' Montreal Cognitive Assessment (Mo CA) subscale scores. Magnetic resonance imaging scans showed that both periventricular hyperintensity ( PVH) and deep white matter hyperintensity were associated with Mini Mental State Examination ( MMSE) and Mo CA scores, but only PVH was related to homeostasis model assessment of insulin resistance scores. Compared with age-matched late elderly normal subjects, 'orientation to time' and 'registration' MMSE subscales declined in late elderly DM patients. Conclusions These results suggest that cognitive and affective decline in DM patients was mostly related to glucose control and insulin resistance, whilst amongst late elderly subjects the impairment of 'attention' and 'orientation' were characteristic features of DM patients. [ABSTRACT FROM AUTHOR]

The superconducting fluctuation effect, due to preformed Cooper pairs above the critical temperature Tc, has been generally understood by the standard Gaussian fluctuation theories in most superconductors. The transverse thermoelectric (Nernst) effect is particularly sensitive to the fluctuations, and the large Nernst signal found in the pseudogap regime of the underdoped cuprates has raised much debate. Here we report on the observation of a colossal Nernst signal due to the superconducting fluctuations in the heavy-fermion superconductor URu2Si2. The Nernst coefficient is anomalously enhanced (by a factor of ∼106) as compared with the theoretically expected value of the Gaussian fluctuations. Moreover, contrary to the conventional wisdom, the enhancement is more significant with a reduction of the impurity scattering rate. This unconventional Nernst effect intimately reflects the highly unusual superconducting state of URu2Si2. The results invoke possible chiral or Berry-phase fluctuations associated with the broken time-reversal symmetry of the superconducting order parameter. [ABSTRACT FROM AUTHOR]

To gain insight into the unconventional superconductivity of Fe pnictides with no electron pockets, we measure the thermal conductivity κ and penetration depth λ in the heavily hole-doped regime of Ba1-xKxFe2As2. The residual thermal conductivity (κ/T)T→0K and T dependence of λ consistently indicate the fully gapped superconductivity at x=0.76 and the (line) nodal superconductivity at higher hole concentrations. The magnitude of κ/TTc∣T→0K and the slope of λ(T) at low temperatures, both of which are determined by the properties of the low-energy excitations, exhibit a highly unusual nonmonotonic x dependence. These results indicate a dramatic change of the nodal characteristics in a narrow doping range. We suggest that the observed x dependence is naturally explained by a doping crossover of the gap function between the s-wave states with and without sign reversal between Γ-centered hole pockets. [ABSTRACT FROM AUTHOR]

Abstract: We have investigated the photoluminescence (PL) dynamics of excitons at the mini-Brillouin-zone edge (k z =π/D), the so-called π point, in a GaAs/AlAs superlattice (SL): D is a SL period. Under the resonant excitation condition of the first quantized (n=1) heavy-hole (HH) exciton at the Γ point (k z =0), it was found that the PL band of the n=1HH exciton at the π point is observed from time-resolved PL spectra. The temporal profile of the PL of the π-point exciton exhibits a considerable delay time, ∼40ps, to that of the Γ-point exciton and a very short decay time, ∼12ps. Note that the PL of the π-point exciton has been never observed under off-resonant excitation of the Γ-point exciton. The delay time is attributed to the transit time from the Γ point to the π point in the mini-Brillouin zone. The very short decay time results from that the π point is a metastable state in the miniband dispersion. The mechanism of the transit process of the excitons is discussed from aspects of excitation-power dependence and scattering by folded longitudinal acoustic phonons peculiar to the SL. [Copyright &y& Elsevier]

Abstract: The growth processes of InP epitaxial layers on InP(111)A P-stabilized surface are theoretically investigated by using our first-principles-based approach which incorporates the growth conditions such as temperature and pressure. Our calculations for adsorption of In and P atoms reveal that the wurtzite structure is feasible at high temperatures with low V/III ratio conditions. On the other hand, at low temperatures with high V/III ratio conditions, the adsorption of P atoms occurs on the surface with In coverage of 0.25, leading to the formation of rotational twins. These results thus imply that the adsorption of P atoms depending on growth conditions plays a role in determining the crystal structure of epitaxial layers on InP(111)A substrates. [Copyright &y& Elsevier]

Abstract: The initial growth processes on InP and InP surfaces are theoretically investigated to clarify temperature and pressure dependence of InP nanowire shape fabricated by selective area growth. Our Monte Carlo simulations in conjunction with density functional calculations for the growth processes with a realistic environment such as temperature and pressure reveal that there are several growth modes depending on the growth conditions. Due to lower growth rate on InP surface compared with InP surface, the nanowires grow along both vertical [0001] and lateral directions for low temperatures with high V/III ratio conditions. On the other hand, at high temperatures with low V/III ratio conditions, the nanowires grow along only vertical [0001] direction and form side facets due to lower surface energy on InP surface. The adsorption of P atoms on the surfaces are found to be crucial for the growth along the lateral direction of nanowires. The obtained results offer a possibility to predict and control nanowire shape by tuning growth conditions such as temperature and pressure. [Copyright &y& Elsevier]

The pencil beam algorithm (PBA) is reasonably accurate and fast. It is, therefore, the primary method used in routine clinical treatment planning for proton radiotherapy; still, it needs to be validated for use in highly inhomogeneous regions. In our investigation of the effect of patient inhomogeneity, PBA was compared with Monte Carlo (MC). A software framework was developed for the MC simulation of radiotherapy based on Geant4. Anatomical sites selected for the comparison were the head/neck, liver, lung and pelvis region. The dose distributions calculated by the two methods in selected examples were compared, as well as a dose volume histogram (DVH) derived from the dose distributions. The comparison of the off-center ratio (OCR) at the iso-center showed good agreement between the PBA and MC, while discrepancies were seen around the distal fall-off regions. While MC showed a fine structure on the OCR in the distal fall-off region, the PBA showed smoother distribution. The fine structures in MC calculation appeared downstream of very low-density regions. Comparison of DVHs showed that most of the target volumes were similarly covered, while some OARs located around the distal region received a higher dose when calculated by MC than the PBA [ABSTRACT FROM AUTHOR]

Study Design: Retrospective chart review. Objective: To assess the impact that routine postoperative radiographs have in clinical outcome and clinical decision-making. Summary Of Background Data: No standard exists that outlines how often and when radiographs should be taken after lumbar fusion. Routine postoperative radiographs can be a source of inconvenience and cost to patients, radiation exposure, and possibly, confounding information. Methods: The patients who underwent a single or multilevel lumbar instrumented fusion were investigated. At each time-point after surgery, it was noted if they demonstrated new symptoms or clinical deterioration. The Fisher exact test was used to analyze the categorical data. Results: Sixty-three patients (25 males and 38 females) were identified with a mean age of 52 years (range, 20-87). Plain radiographs were taken at 269 visits including all time-points. In 17 (6.3%) visits, abnormal findings were found in 13 patients, including suspected pseudoarthrosis on radiographs (n = 10) and adjacent segment disease on radiographs (n = 3). They were found during 11 of 50 visits (22%) in the patients with new symptoms or clinical deterioration and during 6 of 219 visits (2.7%) in the asymptomatic patients. The probability of an abnormal finding was significantly lower in the asymptomatic patients (P < 0.001). Before the 6-month follow-up, abnormal findings were found in 1 of 111 visits (0.9%) and in 16 of 158 visits (10%) at the 6-month follow-up or later. The probability of an abnormal finding was significantly lower before the 6-month follow-up (P < 0.001). In six of the seven symptomatic patients (86%) with suspected pseudoarthrosis on radiographs, pseudoarthrosis was initially suspected between 6 and 12 months after surgery. Conclusion: This study suggests that plain radiographs should be performed as indicated clinically rather than routinely after instrumented lumbar fusion. The vast majority of asymptomatic patients do not require routine postoperative radiographs. [ABSTRACT FROM AUTHOR]

We report on the performance of a fiber-coupled superconducting nanowire single-photon detector (SNSPD) from 4 K down to the ultralow temperature of 16 mK for a 1550 nm wavelength. The system detection efficiency (DE) increased with decreasing the temperature and reached the considerably high value of 15% with a dark count rate less than 100 cps below 1.5 K, even without an optical cavity structure. We also observed saturation of the system DE in its bias current dependency at 16 mK, which indicates that the device DE of our SNSPD nearly reached intrinsic DE despite the device having a large active area of 20\ \mum\times 20\ \mum. The dark count was finite even at 16 mK and the black body radiation becomes its dominant origin in the low temperatures for fiber-coupled devices. [ABSTRACT FROM AUTHOR]

STUDY DESIGN: Prospective observational cohort study. OBJECTIVE: To define the utility of the revised Tokuhashi score in relation to predicting survival in patients with spinal metastases regardless of the treatment pathway. SUMMARY OF BACKGROUND DATA: The revised Tokuhashi score has been used for the prediction of survival. In this scoring system, however, all the patients were sourced by orthopedic surgeons, and asymptomatic patients were excluded. That might present a significant source of patient selection bias. The treatment plan was also affected by the predicted survival in their system. METHODS: All patients within 2 years of diagnosis of spinal metastases, whether symptomatic were recruited. Minimum 1-year follow-up was required. During the study period, a total of 85 patients were analyzed including 44 patients who died within 1 year. The relation between the revised Tokuhashi score and survival were analyzed using the Cox proportional hazard model and Spearman's rank correlation coefficient. RESULTS: The mean age was 60.3 years (range: 35-84) and the median survival was 11.6 months. On multivariate analysis, lower performance status (Karnofsky performance status, 50%-70%) and unresectable organ metastases were significantly associated with poor survival, with hazard ratios of 2.92 and 4.44, respectively. In primary cancer type, lung and kidney cancer were also significantly associated with poor survival, with hazard ratios of 4.25 and 2.60, respectively. The revised Tokuhashi score groups were significantly correlated with the survival groups ([rho] = 0.530, P < 0.001). In 67 (79%) of 85 patients, actual survival matched the predicted survival. CONCLUSION: Lower score on performance status, the existence of organ metastases, and primary cancer of the lung and the kidney were significantly associated with poor survival. The revised Tokuhashi score was found to be very useful to predict survival regardless of the treatment pathway. In most patients, actual survival matched their predicted survival. [ABSTRACT FROM AUTHOR]

STUDY DESIGN.: This is a prospective in vivo study comparing radiation exposure to the surgeon during 10 minimally invasive lumbar microdiscectomy cases with 10 traditional open discectomy cases as a control. OBJECTIVE.: Radiation exposure to the eye, chest, and hand of the operating surgeon during minimally invasive surgery (MIS) and open lumbar microdiscectomy were measured. The Occupational Exposure Guidelines were used to calculate the allowable number of cases per year from the mean values at each of the 3 sites. SUMMARY OF BACKGROUND DATA.: Fluoroscopy is a source of ionizing radiation and as such, is a potential health hazard with continued exposure during surgery. Presently, radiation exposure to the surgeon during MIS lumbar microdiscectomy is unknown. METHODS.: Radiation exposure to the surgeon (millirads [mR]) per case was measured by digital dosimeters placed at the level of the thyroid/eye, chest, and dominant forearm. Other data collected included operative side and level, side of the surgeon, side of the x-ray source, total fluoroscopy time, and energy output. RESULTS.: The average radiation exposure to the surgeon during open cases was thyroid/eye 0.16 ± 0.22 mR, chest 0.21 ± 0.23 mR, and hand 0.20 ± 0.14 mR. During minimally invasive cases exposure to the thyroid/eye was 1.72 ± 1.52 mR, the chest was 3.08 ± 2.93 mR, and the hand was 4.45 ± 3.75 mR. The difference between thyroid/ eye, chest, and hand exposure during open and minimally invasive cases was statistically significant (P = 0.010, P = 0.013, and P = 0.006, respectively). Surgeons standing in an adjacent substerile room during open cases were exposed to 0.2 mR per case. CONCLUSION.: MIS lumbar microdiscectomy cases expose the surgeon to significantly more radiation than open microdiscectomy. One would need to perform 1623 MIS microdiscectomies to exceed the exposure limit for whole-body radiation, 8720 cases for the lens of the eye, and 11,235 cases for the hand. Standing in a substerile room during x-ray localization in open cases is not fully protective. [ABSTRACT FROM AUTHOR]

Background: a fibroblast growth factor 2 (FGF2)-targeted adenoviral system can alter viral tropism and allow for improved transduction and reduced systemic toxicity. This study is to investigate if the FGF2-targeted adenoviral mutant Nijmegen breakage syndrome 1 (FGF2-Ad-NBS1) gene transfer can enhance cisplatin chemosensitisation not only by targeting DNA repair, but also through the induction of antiangiogenesis, whereas at the same time reducing toxicities in treating head and neck squamous cell carcinoma (HNSCC).Methods: the human HNSCC cell line was treated in vitro and in a nude mouse xenograft model. We conducted verification of binding ability of mutant NBS1 and downregulation of MRN complex, evaluation of transduction efficiency and combined antitumour activities. The antiangiogenesis mechanism was also investigated. Finally, we estimated the distribution of adenoviral vector in the liver.Results: the mutant NBS1 protein retains the binding ability and effectively suppresses the expression level of the MRN in infected cells. Transduction efficiency in vitro and cisplatin chemosensitisation were upregulated. The FGF2-Ad-NBS1 also showed detargeting the viral vectors away from the liver. The downregulation of NF-κB expression was supposed to correlate with increased antiangiogenesis.Conclusions: FGF2-targeted adenoviral system enhances the cisplatin chemosensitisation of mutant NBS1 and may avoid viral-associated liver toxicities. [ABSTRACT FROM AUTHOR]

Preemptive therapy is the standard strategy for preventing CMV disease after allogeneic hematopoietic SCT. In this study, unrelated BMT recipients were randomly assigned to a plasma real-time PCR group or an antigenemia group to compare the value of these monitoring tools for CMV reactivation. Ganciclovir (GCV) was started at 5 mg/kg/day when PCR reached 300 copies per ml or when antigenemia reached three positive cells per two slides. A total of 88 patients were randomized into the antigenemia group (n=45) or the PCR group (n=43). A significantly higher number of patients reached the threshold in the antigenemia group than in the PCR group (73.3 vs 44.2%, P=0.0089). However, only three patients (one in the antigenemia group and two in the PCR group) developed early CMV disease. These patients exclusively had colitis and were successfully treated with GCV or foscarnet. The median number of antigenemia-positive cells at the start of GCV was 47 in the PCR group. These findings suggest that antigenemia assay with the current cutoff was too sensitive and led to unnecessary use of GCV. However, the appropriateness of the threshold may be different by the methodology used, and therefore, it is difficult to generalize. [ABSTRACT FROM AUTHOR]

Abstract: We have investigated the effects of differential aspirin doses on atherogenesis. Aspirin was given to homozygous, apoE-/- and LDLR-/- double deficient mice for 12weeks. The development of arteriosclerosis was determined morphologically by image analysis and endothelial cell function was assessed by measurement of peripheral nitric oxide (NO). Methods: ApoE-/- LDLR-/-double knockout mice were bred and maintained with a high fat diet containing aspirin (4 and 40mg/kg B.W. /day) for twelve weeks. The development of arteriosclerosis was monitored by estimating the total area of atherosclerotic lesions in the entire aorta. Acetylcholine-induced NO release was measured in vivo using electrochemical sensors. The expression of eNOS on the endothelial surface was determined by immuno-staining. Plasma prostaglandin F1α (PGF1α), serum thromboxian B2 (TXB2) and total cholesterol were measured using enzymatic assay. Bleeding time was measured by tail cut method. Results: Arteriosclerosis in the 4mg/kg/day aspirin group was decreased significantly compared with the placebo group, but not in the 40mg/kg/day aspirin group. Acetylcholine-induced NO release was significantly depressed in the 40mg/kg/day aspirin group. Immunochemical analysis with anti-eNOS antibody supported these findings. In the 4mg/kg/day aspirin group, the severe suppression of PGI2 production was not confirmed in spite of decreasing TXB2 production, but not in the 40mg/kg/day aspirin group. Conclusion: Our results suggest that endothelial dysfunction with low dose aspirin improved, reduced progression of atherosclerosis in apoE-/- and LDLR-/- double deficient mice and provides a pathophysiological basis for the beneficial effects of aspirin in atherosclerosis, and low doses appeared to be more efficient than high doses. [Copyright &y& Elsevier]

OBJECTIVE: To investigate whether childhood sports participation, particularly weight-bearing sports, has any effect on bone mineral content (BMC), areal bone mineral density (aBMD) and bone geometric characteristics in middle-aged postmenopausal women. Design/ SETTING: In this cross-sectional comparison of two groups, 46 middle-aged women (mean age, 60.2 (SD 5.6) years; range, 52-73 years) were grouped according to sport participation during growth: weight-bearing sports, including high-impact weight-bearing activities; and low-impact non-weight-bearing sports or no participation. MAIN OUTCOME MEASURES: Dual energy X-ray absorptiometry (DXA)-measured BMC, aBMD in the lumbar spine and femur. Magnetic resonance imaging (MRI) determined bone geometric characteristics in the femur, such as femoral mid-diaphyseal cross-sectional area, periosteal and endosteal perimeters and maximum and minimum second moment of area. RESULTS: Postmenopausal middle-aged women with participation in weight-bearing sports during junior high to high school (12-18 years old) displayed significantly greater BMC in both lumbar spine and femoral neck regions, and also significantly greater femoral mid-diaphyseal bone cross-sectional area, periosteal perimeter and maximum and minimum second moment of area than the non-weight-bearing sports group. CONCLUSIONS: Adolescent weight-bearing exercise exerts preservational effects on femoral mid-diaphyseal size and shape, while DXA-measured BMC effectively identified the same tendency. Weight-bearing exercise in youth affects bone, and these effects may be preserved as BMC, geometric and structural advantages even after 40 years. [ABSTRACT FROM AUTHOR]

Study Design. A retrospective study of patients undergoing palliative surgery for metastatic spinal tumors.Objective. To investigate short-term functional recovery and duration of improvement after palliative surgery, to correlate these outcomes with the revised Tokuhashi score, and to examine the relationship between function and neurologic deterioration.Summary of Background Data. The revised Tokuhashi score is a scoring system used to predict life expectancy for patients with metastatic spinal tumors. The relationship between the revised Tokuhashi score and physical functional improvement after palliative surgery has not been examined previously.Methods. The clinical charts of 86 patients were reviewed. The Eastern Cooperative Oncology Group Performance Status (ECOG-PS) was used to assess physical function. Each score was documented before surgery and at every month after surgery. The duration of ECOG-PS improvement, defined as the period between surgery and deterioration to the preoperative ECOG-PS grade, was correlated with the revised Tokuhashi score.Results. The ECOG-PS grade improved in 44 (51.1%) patients at 1 month postoperative. When ECOG-PS improvement was found after surgery, it persisted above the preoperative level for an average of 9.3 months. At 1 month postoperative, patients scoring 0 to 8 on the total revised Tokuhashi score had significantly lower ECOG-PS improvement (26 of 55 patients) when compared to patients with higher scores (18 of 27 patients, P < 0.05). In 44 patients with ECOG-PS improvement, the existence of major internal organ metastases significantly shortened the duration of improvement (P < 0.05).Conclusion. Palliative surgery benefited half of the patients with metastatic spinal tumor, with a greater probability of benefit found in persons with a higher total revised Tokuhashi score (score 9-15) and/or primary cancers with longer survival times. [ABSTRACT FROM AUTHOR]

Abstract: A numerical model has been developed to simulate Cu precipitation in dilute bcc Fe–Cu alloys during non-isothermal aging taking into account competitive nucleation at grain boundaries, dislocations and in the matrix, and structural transformation of Cu particles that occurs during growth. The temporal evolution of number density, mean particle size and size distribution during continuous cooling is simulated and is compared with experimental observations under transmission electron microscope and three-dimensional atom probe field ion microscope. With decreasing temperature the growth and coarsening rates diminishes rapidly whereas nucleation continues to occur down to lower temperatures due to the decrease in the activation energy of nucleation and thus, distributions of fine particles can be obtained relatively easily after cooling. Precipitation and dissolution during continuous heating are simulated and are compared with experimental observations in the literature. [Copyright &y& Elsevier]

Abstract: Prediction of pulverized coal ignition behavior in a 40MW tangentially fired commercial boiler is studied. Pulverized coal combustion simulation is performed considering radiation properties of particles. Coal devolatilization and char combustion are modeled and the first order spherical harmonic approximation is used to model the radiative transfer equation. To confirm the accuracy of the simulation method, the results are confirmed by available operating data, design data, and the ignition image in the boiler whose inside is observed by the developed high temperature resistant CCD video camera system. The work indicates that the simulation method can be applied to commercial boilers and predict the ignition behavior with considering not only coal properties but also boiler operating conditions. [Copyright &y& Elsevier]

In applying Pressure-Sensitive Paint (PSP) to low-speed flow wind tunnel testing, it is important to minimize any measurement uncertainties. There are various error sources such as camera noise, misalignment of images due to model displacement and temperature distribution over the model. Among these factors, the effects of temperature distribution change during tests on pressure measurement accuracies were studied in the present paper. Pressure and temperature distributions over a simplified car model (1/10 scale Ahmed model) were measured using PSP and Temperature-Sensitive Paint (TSP). Sequential images were acquired at the same intervals over the entire test period, including for the conditions before and after the tunnel run. As a result, it was found that the measurement error caused by temperature distribution over the model could be reduced using a single-point temperature measurement. In addition, by measuring surface temperature distributions on the model using TSP, it was proved that the most accurate pressure measurement could be made by rationing the wind-off image acquired immediately after shutting down the tunnel to the wind-on image acquired immediately before shutting down the tunnel. Using the present measurement technique, complicated pressure fields over the Ahmed model were successfully visualized. [ABSTRACT FROM AUTHOR]

Abstract: Single phase (Ca1−x Na x )MnO3−δ with 0≤ x ≤0.025 is successfully fabricated using a solid state reaction in air. Electrical resistivity measurements indicate that oxygen vacancies are introduced into the (Ca1−x Na x )MnO3−δ at high Na concentration (0.02≤ x). The hole carriers may be doped in (Ca0.99Na0.01)MnO3−α which has the lowest resistivity and smallest band gap. The highest signal for the imaginary part of magnetic susceptibility is shown by (Ca0.99Na0.01)MnO3−α at about 115K. This high signal may be due to magnetic interactions between Mn4+ and Mn6+. [Copyright &y& Elsevier]

Abstract: We consider an interacting particle system for the stock price fluctuation. The change of the stock price with a feedback by the price considering the herding behavior (majority orienting behavior) of traders, gives the van der Pol equation as a deterministic approximation. Considering the investment position of each trader, we introduce the delayed van der Pol equation. The history of investment positions, for example sell or buy, of each trader for a stock makes a memory effect, which is modeled by using the time retardation. The delayed van der Pol equation model seems to be natural and explains typical phenomena, for example triangle pattern, volatility jumps, price jumps and price trends, known for the time series of a stock price. [Copyright &y& Elsevier]

Abstract: We have fabricated the submicron structures using high-T c superconducting materials of Bi2Sr2CuO6+δ (Bi-2201). The stacks of layered structures are made by focused-ion-beam (FIB) etching methods. The fabricated 3D three terminal devices consist of source, drain and gate electrodes on the same chip. A gate electrode is capacitively coupled to a central island between two ultra-small tunnel junctions with in plane area S =0.25μm2 in series. Two stacks including an island structure show a Coulomb blockade region of 15mV at zero gate potential. The effects are not smeared out by thermal fluctuations until temperatures greater than 150K are reached. [Copyright &y& Elsevier]

Single phase (Zn,Fe)1− x O zincite solid solution samples have been prepared by high temperature equilibration in air and in reducing atmospheres, followed by quenching to room temperature. The Fe2+/Fe3+ concentrations in the samples have been determined using wet chemical and XPS techniques. Iron is found to be present in zincite predominantly in the form of Fe3+ ions. The transition from an equiaxed grain morphology to plate-like zincite crystals is shown to be associated with increasing Fe3+ concentration, increasing elongation in <001> of the hexagonal crystals and increasing anisotropic strain along the c-axis. The plate-like crystals are shown to contain planar defects and zincite polytypes at high iron concentrations. [ABSTRACT FROM AUTHOR]

A new anaerobic-oxic biological filter reactor, which was packed with carbon fibre and aerated with micro-bubbles, was proposed. The reactor performance was examined using dye works wastewater compared with the activated sludge reactor. Effluent SS from the experimental reactor was significantly lower than that from the activated sludge reactor, and transparency was higher. Temperatures of the activated sludge reactor were over 35°C and DOC removal ratios were 40–80% depending on the influent wastewater. On the other hand, the DOC removal efficiency of the experimental reactor was over 70%, when the reactor temperature was over 22 °C. In the anaerobic zone, sulphate reduction occurred predominantly and acetate was produced. In the oxic reactor, sulphur oxidation and organic removal occurred. When the amount of sulphate reduction in the anaerobic zone increased, DOC and colour in effluent decreased. The sulphate reducing activity of biofilm at 30 °C was three times higher than those at 20°C. The sulphate reducing activity of biofilm in the oxic zone was higher than those in the anaerobic zone, meaning that the sulphate reduction-oxidation cycles were established in the biofilm of the oxic zone. Microbial community of sulphate reducing bacteria was examined by in situ hybridisaton with 16S rRNA targeted oligonucleotide probes. Desulfobulbus spp. was most common sulphate reducing bacteria in the anaerobic zone. In the oxic zone, Desulfobulbus spp. and Desulfococcus spp. were observed. [ABSTRACT FROM AUTHOR]