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The highly textured Nd0.6Sr0.4MnO3 thin films with different thickness t were obtained. The maximum magnetoresistance (MR) ratio, defined as [R(0)−R(1.5 T )]/R(0) at the insulating- to metallic-phase transition temperature, was found to increase with decreasing t, reaching a value of 75% for t=500 A. However, when t was further decreased down to 100 A, the MR ratio was not significantly affected. In conjunction with our topographic results, we have attributed the saturation of MR ratio to the achieving of an optimized interface strain.

The magnetic structure of colossal magneto-resistive Nd 0.7 Sr 0.3 (Mn 1− x 57 Fe x )O 3 ( x =0.02, 0.05, 0.10, and 0.15) has been studied by Mossbauer spectroscopy in magnetic fields up to 60 kG. 57 Fe ions appear to spread over two different magnetic phases. One of them remains ferromagnetic for all values of x , but the other one changes from canted to anti-ferromagnetic with increasing x . For x =0.02 and 0.05, the latter magnetic phase is comprised of small clusters, which are very sensitive temperature and strongly influenced by the applied fields.

We have systematically studied the pressure ( P ) effects on the normal state resistivity and on the superconducting transition temperature T c for the series of (Nd 1− x Pr x )Ba 2 Cu 3 O 7 . Our results show that the functions T c ( x ) and d T c /d P ( x ) are not directly related to each other, suggesting that the factor controlling the x -dependent T c in (Nd 1− x Pr x )Ba 2 Cu 3 O 7 is not sensitive to pressure. However, we have found that the x dependency of d T c /d P is strongly correlated to the x dependency of the pressure effect on carrier concentration. We therefore attribute the origin of pressure-induced T c variation in (Nd 1− x Pr x )Ba 2 Cu 3 O 7 to a combined effect of pressure-induced charge transfer and pressure-induced hole depletion.

The strong thermal hysteresis of thermoelectric power (TEP) in Pr0.5(Sr, Ca)0.5MnO3 is observed. A simple estimation shows that the electrostatic energy between Mn3+/Mn4+ alone cannot account for the large shift of Tco with changing A size. Based on our experimental evidence, we attribute the distinct features exhibited in the thermal hysteresis to the manifestation of the underlying competition between the delocalization and localization effects assisted respectively by the double exchange interaction and the charge ordering. The observed features include the following: (1) the A-size effect can depress Tco by as much as 70 K for Pr0.5Sr0.5-xCaxMnO3; (2) large thermal hysteresis of resistivity and TEP are exhibited in Pr0.5Sr0.5-xCaxMnO3; (3) for x = 0.3 and 0.4, the thermal hysteresis is larger than those of x = 0.1 and 0.5 and (4) magnetic field induces a large shift in Tco.

The temperature dependent thermoelectric power (TEP) for a series of superconducting Y(Ba 2− x Sr x )Cu 3 O 6.95 with x =0 to 0.8 has been investigated. We have kept the oxygen content at the optimal value (6.95±0.02) and have changed the lattice parameters by Sr-doping to study the strain dependent TEP. We have observed that a hump occurs at 240 K for all samples except that with x =0. With increasing the Sr-doping level, S shifts to a higher value and changes its sign from negative to positive. This study demonstrates that the sign as well as the absolute value of TEP has been affected by the lattice strains.

A compact multichannel Superheated Superconducting Grain detector (SSG) has been irradiated by the T9 beam (mostly composed by high energy electrons) of the SPS machine at CERN. The SSG detector consists of a set of cylindrical suspensions of tin grains with various filling factors, all of them parallel to the beam line and kept in an 3 He – 4 He single-dilution chamber. Transitions to the normal state of the grains were detected with a GaAs high electron mobility field effect transistor (HEMFET) preamplifier cooled to 4.2 K. We present a preliminary analysis of the results obtained with beam energies from 1 to 14 GeV and a 33–37 μm size distribution of the grains.

Flip chip on board (FCOB) technology involves the bonding of a bare die directly onto a printed circuit board (PCB). The interconnections are provided by solder bumps which are arranged in the area under the chip. Encapsulation is the preferred process to reduce the impact of the thermal stress that results from the mismatch in the coefficient of thermal expansion (CTE) between the silicon chip and the substrate. The length of time needed for the dispensing and capillary flow of the encapsulant is one of the important factors that inhibits the high volume use of FCOB technology. Preheating the substrate prior to and during the dispensing of the encapsulant enhances its flow characteristics by reducing its viscosity. This research addressed the feasibility of using a substrate preheat temperature which is higher than the manufacturer's recommendation in order to reduce the cycle time of the encapsulation process while still ensuring package reliability. Defects that may be caused by increasing the substrate preheat temperature are discussed and evaluated. A statistical model was generated to help determine the optimal substrate preheat temperature for given chip dimensions, standoff height, surface texture, etc. Using the substrate preheat temperature determined by the model, the flow time of the encapsulant could be reduced by more than a factor of two while still ensuring a 6σ quality level.

Simultaneous measurements of transmitted 500 kHz electric fields and of electron fluxes nonlinearly energized by those fields were made during the ionospheric flight of the rocket double payload OEDIPUS C. Given the local plasma parameters, 500 kHz corresponded to the whistler mode of cold-plasma propagation. As the separation between each payload end increased from 153 to 537 m, enhanced electron fluxes were detected at energies up to 20 keV, at the receiver end of the tether. Rf (radio frequency) electric fields created by the OEDIPUS-C transmitter have been computed for positions close to the whistler-mode group resonance cone and also for locations very close to the active dipoles. Test-particle trajectory tracings show that linear acceleration can account for the energy increases of electrons with starting energies up to about 100 eV. Neither resonant field-particle interactions of background energetic electrons nor strong turbulence of the background thermal particles explain the creation of sounder-accelerated electrons at 1–10 keV. The calculated magnitudes of the very near potentials, up to 550 V, point to acceleration by intense fields in the rf sheath region.

This study aims to create an engineering application in a server that will facilitate access by other engineers via the World Wide Web (WWW) from some more remote personal computers. To design a routine low-height cantilever retaining wall, several databases are generated in this study including the topographical drawing of Taiwan, standard profiles and details of a series of selected retaining walls, data for design interpolation, information about existing retaining walls, etc. How to create usable databases and to interpolate them to meet engineering requirements are the two important subjects being studied. Those created data represent a central pool, which can serve to fulfill the requirement of a complete retaining wall design from a remote personal computer by WWW techniques. Thus, via the transformation of alphanumerical data, as well as images, the information can be obtained from the generated databases in this study, including the optimized dimensions of a wall in a design, the required additional forces for reinforcing an existing wall to satisfy a design, and the status of those local existing walls at any specified spot in the country.

The magnetic and electrical properties of the colossal magnetoresistance (CMR) La1.2(Sr1.8−xCax)Mn2O7 materials have been investigated. Based on the chemical titration method, the valence of Mn was determined to be 3.39±0.04 for all measured La1.2(Sr1.8−xCax)Mn2O7. The magnetoresistance ratio [ρ(0)/ρ(H)] was efficiently increased from ∼192% (135 K, 1.5 T) for x=0 to 208% (102 K, 1.5 T) for x=0.4 in La1.2(Sr1.8−xCax)Mn2O7. Moreover, the Curie temperature (Tc) decreased with increasing x and was strongly dependent on the apical bond lengths of Mn–O(2).

A novel photonic transmitter for wireless terahertz (THz) impulse-radio (IR) communication is realized by monolithic integration of a GaAs-AlGaAs-based uni-traveling-carrier (UTC) photodiode with a substrate-removed broadband antenna. The device can radiate strong sub-THz pulses (20-mW peak-power) with a narrow pulsewidth (

The photorefractive properties of BaTiO3 are gradually modified by the addition of Nb which change the charge carrier from hole to electron. Before the compensation point, the dark conductivity decreases and the response time increases with increasing Nb concentration. Two beam coupling gain can be explained by using the deep and shallow trap model with hole as the major carrier. Near the compensation point, the deep and shallow trap model is needed, in addition to the electron–hole competition to explain this. After the compensation point, an absorption around 600 nm evolves, the dark conductivity increases very fast, and the electron becomes the major carrier.

The effect of doping Cr in the Mn site of the La1.2Sr1.8Mn2O7 system has been studied. Addition of Cr modifies the transport and magnetic properties of the parent phase. With increasing Cr, the insulator-metal transition observed in the parent phase is suppressed and insulating behaviour is induced. In the range of doping studied (25%), the compositions show ferromagnetic behaviour with the Curie temperature decreasing with increasing Cr. The unit cell volume also shows a decrease. However, the magnetoresistance ratio is not significantly affected. We compare these results with an earlier study of doping Cr in the three-dimensional LaMnO3 structure, where it was seen that the ferromagnetic and magnetoresistance characteristics are sensitive to Cr doping. The results of the present study suggest that the layered manganates are more accommodative to doping compared to the three-dimensional perovskites.

Modulations of electron and ion fluxes in the frequency ranges 0 – 10 MHz and 0 – 10 kHz were monitored by the Shuttle Potential and Return Electron Experiment (SPREE) during electron beam experiments conducted on the Tethered Satellite System missions. Electron fluxes detected by SPREE were modulated at megahertz frequencies only when beams were emitted at large pitch angles with respect to the Earth's magnetic field. High frequency modulations fall into two classes close to: (1) even or odd half harmonics of the electron gyrofrequency if beam pitch angle α B ≈ 90°, and (2) harmonics of estimated plasma frequencies if 60° > α B > 45°. When SPREE intercepted beam electrons after one gyroturn, they were modulated at the same frequencies as secondary electrons. These measurements indicate that beam electrons propagate in cylindrical shells whose inner edge is marked by steep spatial gradients in fluxes of beam electrons. Inside the shell, electron distribution functions have positive velocity space slopes at energies near that of the beam. These gradients act as free energy sources to drive cavity modes that alter the instantaneous guiding centers of electrons causing SPREE to sample alternating parts of the beam cylinder's inner edge. Associated time-varying electric fields also modulated the fluxes of secondary electrons reaching SPREE. Low kilohertz modulations, detected at all beam pitch angles, correspond to no natural plasma mode and are interpreted as signatures of large-amplitude, ion acoustic-like waves excited through Cerenkov interactions between electron beams and ambient plasmas as the shuttle moved at supersonic speeds across the ionosphere. This hypothesis is confirmed by the simultaneous detection of electrons and ions modulated at the same frequencies when the shuttle was negatively charged. These results explain the sources of coherent whistler and ion acoustic-like waves detected during electron beam experiments of Spacelab 2.

The magnetic properties and thermal evolution of Tb 0.85 Na 0.15 MnO 3-y have been studied by neutron-diffraction experiments. By comparison with the TbMnO 3 sample, the results show not only small lattice parameters but also a reduction in correlation length (ξ). This is strongly correlated to the induced oxygen vacancies in Tb 0.85 Na 0.15 MnO 3-y [y≈0.15(2)].

The size dependence of magnetization reversal of magnetic tunnel junction (MTJ) rings has been investigated. The MTJ rings, with outer diameter of 4, 2 and 1 μm and inner diameter of 1.5, 1 and 0.5 μm were fabricated by a top–down technique. The magnetoresistance curves manifest all of the magnetic domain configurations during magnetization reversal in different sized rings. Various transition processes were observed, such as four transition, three transition and two transition in the largest, middle and smallest MTJ ring, respectively. Furthermore, the biasing fields observed from major loops decrease with decreasing size, which may result from edge roughness produced in the ion-milling process.

We compare equatorward/earthward boundaries of convection electric fields and auroral/plasma sheet electrons detected by the DMSP F8 and CRRES satellites during the June 1991 magnetic storm. Measurements come from the dusk magnetic local time sector where the ring current penetrates closest to the Earth. The storm was triggered by a rapid increase in the solar wind dynamic pressure accompanied by a southward turning of the interplanetary magnetic field (IMF). Satellite data show the following: (1) all particle and field boundaries moved equatorward/earthward during the initial phase, probably in response to the strong southward IMF turning; (2) electric field boundaries were either at lower magnetic L shells or close to the inner edge of ring current ions throughout the main and early recovery phases. Penetration earthward of the ring current occurred twice as the polar cap potential increased rapidly; (3) electric potentials at subauroral latitudes were large fractions of the total potentials in the afternoon cell, twice exceeding 60 kV; and (4) the boundaries of auroral electron precipitation were more variable than those of electric fields and mapped to lower L shells than where CRRES encountered plasma sheet electrons. Observations qualitatively agree with predictions of empirical models for auroral electron and electric field boundaries.

Magnetic and electrical Freedericksz measurements were performed on the second generation monodendritic liquid crystal G2(OH). The deduced elastic constants were found to be exceptionally anisotropic: the splay elastic constant K11 is more than an order of magnitude larger than the bend elastic constant K33, and the twist constant K22 is approximately twice K33. The results are discussed in terms of molecular conformations.

This paper provides details pertaining to computer integrated design systems for low height cantilever retaining walls. A database is created by modifying an existing design chart using numerical analysis. This database then represents a central pool for all the information involved in the modelling of a complete design. All of the operation information is under interactive graphic control. Using this system, one can obtain optimum dimensions for designs quickly, satisfying any predefined safety factors. Viewing the profile of a design at any stage in the process is another benefit to this system. In the case of an existing retaining wall structure, in order to meet assigned safety factors, this system can also evaluate the force required on anchors to reinforce the structure. Discussions on a sloped base design of a retaining wall are also included in this study.

Ion drift measurements from DMSP F13 provide the first opportunity to study the evolution of high latitude potentials in both hemispheres as a magnetic cloud passed Earth. Early in the event with IMF B Z strongly southward, the polar cap expanded and the potential measured across it reached 174 kV, then decreased as the IMF rotated toward B Y < 0. During the initial northward IMF phase convection in the polar cap was dominated by large lobe cells, clockwise in the southern and counterclockwise in the northern hemisphere. With purely northward IMF, convection patterns had four cells and were irregular on the day and night sides of the magnetic dawn-dusk meridian. Potential distributions measured with a southward or westward IMF agree with predictions of the Weimer [1996] model, suggesting that some global MHD simulations overestimate dayside merging rates.

During the Tethered Satellite System reflight the Spacecraft Particle Correlation Experiment detected fluxes of energetic electrons and ions that were simultaneously modulated at low frequencies during firings of both the fast pulsed electron gun (FPEG) and the electron generator assembly (EGA). The modulations have been interpreted as signatures of large-amplitude, ion acoustic-like waves excited in Cerenkov interactions between electron beams and ambient plasmas as the shuttle moved at supersonic speeds across the ionospheric magnetic field. We present examples of particle modulations observed during steady beam emissions. Measurements show that (1) most electron modulations were at frequencies of several hundred Hertz and (2) ions modulated at similar frequencies appeared at spectral energy peaks during shuttle negative charging events. Detection of modulated ion fluxes confirms the Cerenkov emission hypothesis. Observed frequency variations indicate that the EGA beam underwent more spatial spreading than the FPEG beam.

During the reflight of the tethered satellite system, the electron generator assembly (EGA) emitted steady electron beams six times with the satellite deployed between 6.2 and 16.1 km. Maximum beam energies and currents were 1.65 keV and 0.4 A, respectively. Data presented here show that: (1) emissions create local electron clouds that can charge the shuttle, (2) ionization of thruster gas by beam electrons in the sheath did not reduce the shuttle potential, (3) the EGA utilizes more than half the induced potential, and (4) ionospheric density gradients and magnetic field orientations affect the circuit's potential distribution.

We present environmental responses ob- served by the Shuttle Potential and Return Electron Experiment during 13 prolonged electron beam emis- sions from the Fast Pulsed Electron Generator (FPEG) during the TSS 1R deployment. As the tether length- ened from 0.18 to 2.5 kin, FPEG fired nine times at a nominal current of 100 mA at 1 keV. The motional potential induced across the system increased from 24 to 225 V. With a 15 fl resistor connecting the tether to shuttle ground, current was higher and the degree of negative shuttle charging lower when FPEG was off than when it was on. While most FPEG firings left the shuttle uncharged, two created significant poten- tials: one to +70 V in a nighttime, equatorial plasma depletion and one to-60 V, with the tether -15 km. the tether end and shuttle ground. The second, the Fast Pulsed Electron Generator (FPEG), emitted electrons at a fixed energy and current of 1 keV and 100 mA. This paper presents ionospheric plasma responses to extended FPEG emissions detected in the payload bay by the Shuttle Potential and Return Electron Exper- iment (SPREE). We briefly describe SPREE, FPEG and the TSS 1R circuit during FPEG operations, then present SPREE spectral data for 13 FPEG firings. Two events illustrate positive and negative shuttle charging. The last section discusses the shuttle's electrical cou

We studied 21 intervals during the TSS 1R deployment with a 15 Ω or 25 kΩ resistor connecting the tether to shuttle ground. Ion spectral peaks detected by the Shuttle Potential and Return Electron Experiment indicate that the shuttle consistently charged negatively with respect to the local plasma. With the 15 Ω shunt in the circuit, shuttle potential, Φs, decreased from −17 to −245 V as tether length, L, increased to 2.6 km. Current in the circuit depended strongly on ionospheric density. With the 25 kΩ resistor in place, Φs ≈ −300 V in the low density, nightside ionosphere with L = 5.1 km. Near local noon Φs ≈ −80 V with L = 17.2 km. The shuttle charged to ∼−600 V during two dawn terminator crossings, one with and one without thruster firings. As on TSS 1, firings of two aft vernier thrusters significantly increased |Φs|. In the case without thruster firings, simultaneous variations of Φs, tether current, and the inferred satellite potential are consistent with strong azimuthal and vertical ionospheric density gradients. These are the first known direct measurements of strong negative shuttle charging.

Experiments were conducted during the Tethered Satellite System Reflight in which a 1 keV, 100 mA electron beam was emitted from the shuttle at pitch angles near 90°. Rapid plasma responses measured by the Shuttle Potential and Return Electron Experiment (SPREE) show time-modulated electron fluxes within the beam flux tube. Megahertz modulations fall into two classes: (1) narrow-bands close to harmonics of the electron gyrofrequency fce and (2) broad-bands at interharmonic frequencies in which electrons of different energies had different modulation frequencies. When SPREE intercepted beam electrons after a single gyroturn they, too, were modulated at similar frequencies. Data suggest that beam electrons were modulated by strong plasma interactions near the emission aperture, generating time-varying electric fields that modulated other electrons near the beam cylinder. This is analogous to the electron cyclotron maser responsible for auroral kilometric radiation.

In this work, we study the preparation and properties of bio-compatible magnetic nanoparticles for immunoassay and DNA detection. The magnetite (Fe3O4) nanoparticles were prepared by a chemical co-precipitation method and dextran was selected as the surfactant to suspend the nanoparticles. Suspended particles associated with avidin followed by biotin were qualitatively analyzed by enzyme-linked immunosorbent assay (ELISA) method. We found further the ethylenediamine blocked activated residual groups efficiently, hence enhancing the attachment of biotin for probing the avidin.

Great works of art are strangers at home. They defamiliarize what is part of everyday experience while offering something recognizable through the conventions of a genre, and new genres often herald new cultural formations. The Renaissance in Europe revived tragedy and transformed it from a narrative form into a dramatic genre. The Enlightenment and the emergence of the reading public led to the rise of the novel as a dominant form of cultural expression.1 In turn, twentieth-century postcolonial consciousness is deeply ingrained in the European novel, African oral traditions, and myths. In Asia, the I-novel (shishoōsetsu) is not only a striking form of autobiographical fiction but also the hallmark of early twentieth-century, Taishō-era Japanese literature. The birth of modern, industrialized China coincides with that of translated literature, spoken drama (huaju), and other new genres—both literary and performative. With the technologically sophisticated film studios in Shanghai, for instance, modern Chinese aesthetics emerged through the cinema as a dominant form of entertainment in the twentieth century.

We realized electrically-driven subwavelength optical nanocircuits integrating gap plasmon emitting nano-LEDs and deep-subwavelength slot waveguides with a cross-sectional area of ∼0.016λ2 for the first time. The Purcell enhancement within the extremely small, metal-clad active region of the nano-LED enables to extract gap plasmons propagating along the low-loss slot waveguide efficiently and route them to the nanocircuit elements, such as bends, T-splitters, free-space couplers and directional couplers. The electrically-driven optical nanocircuits will provide a meaningful step for interfacing high-speed photonic devices and ultra-compact electronic components and thus solving the interconnect problem.

We demonstrated electrically-driven subwavelength surface plasmonic nano-circuits integrating gap-plasmon emitting nano-LEDs and deep-subwavelength slot waveguides with a cross-sectional area of ~0.016λ2 for the first time. Owing to the Purcell enhancement within the extremely small, metal-clad active region of the nano-LED, gap-plasmons are extracted efficiently. The gap-plasmons propagating along the low-loss slot waveguide are routed to bends, T-splitters, free-space couplers and directional couplers. The electrically-driven surface plasmonic nano-circuits will provide a meaningful step for interfacing high-speed photonic devices and ultra-compact electronic components.

O K-edge and Cu L{sub 23}-edge x-ray-absorption near-edge structure (XANES) spectra for the series of (Dy{sub 1{minus}x}Pr{sub x})Ba{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} compounds (x=0{endash}0.7) were measured to investigate how the variation of hole states related to the superconductivity. Near the O 1s edge, prepeaks at {approximately}527.6 and {approximately}528.4 eV are assigned to transitions into O 2p holes located in the CuO{sub 3} ribbons and CuO{sub 2} planes, respectively. Both the O 2p hole concentration in the CuO{sub 2} planes and CuO{sub 3} ribbons decrease monotonically with increasing Pr doping, giving evidence in support of the hole depletion model proposed by Liechtenstein and Mazin. It clearly demonstrates that the suppression of superconductivity with Pr-doping results predominantly from the hole depletion effect. In the Cu 2p absorption edge, the high-energy shoulders originating from Cu3d{sup 9}L defected states show a linear decrease in spectral weight as the Pr doping increases, where L denotes the ligand O 2p hole on the CuO{sub 3} ribbons and the CuO{sub 2} planes. {copyright} {ital 1997} {ital The American Physical Society}

Utilization of polyhydroxylated C 60 in a condensation reaction with diisocyanated oligo(tetramethylene oxide) led to the successful fabrication of elastomeric poly(urethane-ether) networks. These polymer networks exhibit interesting thermal behavior at low temperatures, improved tensile strength and elongation at ambient temperatures, and enhanced thermal mechanical stability at high temperatures. Design of conducting elastomers was made by carrying out an in situ polymerization of conductive polymer precursors in an interpenetrating fashion at the near-surface of polyhydroxylated C 60 -hypercrosslinked elastomers. Results demonstrated that elastomers with an appreciable conductivity while retaining desirable elastic properties of the network can be achieved. The room-temperature conductivity of polyaniline interpenetrated (IPN) conducting elastomer was found to be 2.0 Scm -1 . The tensile strength and elongation at break of one conductive IPN elastomer was found to be 20 MPa and 480%, respectively. Interestingly, the strain dependent conductivity of these conducting elastomers was found to increase progressively above 200% of elongation. These results demonstrated, for the first instance, conductivity measurements of organic conducting elastomers at an elongation length of higher than 300%, showing a r.t. conductivity of >4.0 SCm -1 .

A processing technique for fabrication of conductive elastomers was demonstrated involving in situ polymerization of aniline at the near-surface region of the fullerenol crosslinked poly(urethane-ether) networks. The synthetic chemistry led to a thin layer (roughly 20 μm in thickness) of conductive polyanilines interpenetrated inside the elastomer matrix. This IPN network exhibited an appreciable conductivity along the doped polyaniline layer without deteriorating much the elasticity and tensile strength of the parent supporting elastomer. As a result, its r.t. conductivity was found to be 2.6 Scm−1 which increased to 5.4 Scm−1 at 430% elongation of the polymer film. The data represented the strain-dependent electronic properties of conducting elastomers, showing an increase of conductivity even after the elastomer being stretched above a length as much as 500% of its original size.

New plasmonic materials with tunable properties are in great need for nanophotonics and metamaterials applications. Here we present two-dimensional layered, metal chalcogenides as tunable metamaterials that feature both dielectric photonic and plasmonic modes across a wide spectral range from the infrared to ultraviolet. The anisotropic layered structure allows intercalation of organic molecules and metal atoms at the van der Waals gap of the host chalcogenide, presenting a chemical route to create heterostructures with molecular and atomic precision for photonic and plasmonic applications. This marks a departure from a lithographic method to create metamaterials. Monochromated electron energy-loss spectroscopy in a scanning transmission electron microscope was used to first establish the presence of the dielectric photonic and plasmonic modes in M2E3 (M = Bi, Sb; E = Se, Te) nanoplates and to observe marked changes in these modes after chemical intercalation. We show that these modal properties can also be tuned effectively by more conventional methods such as thickness control and alloy composition of the nanoplates.

Backgrounds and Aims Ali-San Tsou (AST) is one of leading aboriginal tribes in Taiwan with traditional godly beliefs related to life and death. Lacking related knowledge, health professionals (HPs) often failed to help them reach good dying or organ donation (OD). This study aimed to explore hindering factors and suggestions related to OD for good dying from Taiwan AST's own perspective. Methods An explorative qualitative design was employed using a purposive sample of the AST tribes from Taiwan. Data were collected with AST residents by face-to-face interviews and analyzed by content analysis. Results Thirty AST residents (16 females and 14 males) with ages ranging from 28 to 78 (mean, 54.5) years completed interviews. Of them, 85% reported various diseases. In this study 73% were Catholics and Christians, 17% held traditional godly believes, and 10% had no religious affiliation. Eight hindering factors were reported: (1) limited information about organs and OD; (2) no qualified organs for donation; (3) worry about lack of forgiveness by ancestors; (4) tribe elders who might not accept concept of OD; (5) intact bodies were required at home during spirit-companion rituals; (6) earth burial with intact bodies was preferred; (7) bodies due to accidental and bad death were impermissible for OD; and (8) worry about possession by the donor's spirit. Seven suggestions were also reported for HPs to enhance AST's OD decisions: (1) starting with friendship and a caring relationship; (2) providing spiritual support from reverent religions; (3) stressing good deeds and honoring tribe folks by OD; (4) avoiding accidental/bad death; (5) providing relevant modern medical knowledge of human organs and OD; (6) introducing OD as part of a good-dying care plan; and (7) demonstrating a respectful discussion mindset about OD. Conclusions Eight hindering factors and 7 types of suggestions for enhancing AST aboriginal people's OD decisions were first explored in this project. In the future, HPs are encouraged to invite AST to share the concepts of OT and try to clarify the related concerns with respect for their cultural contexts. With mutual respect, the efforts of sharing and integrating OD into good-dying care would be more possible.

Thrombomodulin (TM) is the endothelial cell membrane-bound anticoagulant protein cofactor in the thrombin-mediated activation of protein C. Previous evidence has been reported regarding the association between TM polymorphisms and coronary artery disease. Allograft rejection-mediated vasculopathy is the main cause of death at more than one year after heart transplantation. However, whether TM polymorphism is associated with allograft rejection is still unclear. We analyzed the TM gene polymorphism C1418T using allele-specific primers in a PCR assay in 60 patients who underwent heart transplantation. The retrospective clinical data were collected and tested for any correlations with the TM gene polymorphism. We separated the patients into 2 groups according to their TM genotype (group 1: CC genotype; group 2: CT or TT genotype). Additionally, we generated expression constructs (TM full length-C1418 and TM full length-T1418) and performed in vitro studies to explore the correlation between the TM C1418T polymorphism and the migration of smooth muscle progenitor cells and monocytes, which may be involved in the development of vasculopathy. The results showed that the levels of CD68, C4d, PAS, and Masson staining in the CT/TT genotype group increased at year 1 and continued to increase throughout the 3 years. These levels were higher than those observed in the CC genotype group. The ISHLT-WF2004 grade of the CT/TT genotype group was significantly different from that of the CC genotype group at the same time point post-transplantation. The coronary allograft vasculopathy (CAV) score was significantly different between the CC and CT/TT genotype groups at 1 and 3 years post-transplantation. Our in vitro studies demonstrate that both smooth muscle progenitor cells and monocytic THP-1 cells with either the CT-1418 or the TT-1418 TM genotype have higher migratory abilities than cells with the CC-1418 genotype. Our results support a significant association between the TM C1418T polymorphism and the development of CAV after heart transplantation in the short- to medium-term.

The temperature dependence of two-beam coupling and dark decay in photorefractive BaTiO3 is reported. We show that the competition between deep and shallow traps depends on temperature and writing intensity, and influences two-beam coupling and dark decay. The dynamics of dark decay, characterized by a fast decay of partial erasure and a subsequent slow decay, is influenced by the presence of deep and shallow traps. Partial erasure, due to thermal excitation of charges from the shallow traps, decreases with temperature and increases with writing intensity. The time constant of the slow decay, due to thermal excitation of charges from the deep traps, depends strongly on temperature, but not on the writing intensity. At room temperature, the existence of deep and shallow trap leads to intensity-dependent photorefractive gains. As temperature increases, the influence from the shallow trap decreases, and the photorefractive gain becomes independent of the intensity. However, at much higher temperatures (∼100°C), the photorefractive gain resumes its dependence on intensity due to an increase in dark conductivity at elevated temperature.

The condensation of H2O on ice multilayers on Ru(001) was studied using both molecular beam and optical interference techniques as a function of surface temperature. From the beam reflection technique, the H2O sticking coefficient, S, was determined to be S = 0.99 ± 0.03 at temperatures between 85 and 150 K and was independent of incident angle (0−70°) and beam energy (1−40 kcal/mol). The condensation coefficient, α, was dependent on both the incident H2O flux and the desorption H2O flux at the various surface temperatures. The magnitude of α varied continuously from unity at T < 130 K to zero at higher temperatures. The optical interference experiments yielded condensation coefficients and sticking coefficients of α = S = 0.97 ± 0.10 at temperatures from 97 to 145 K where the H2O desorption flux was negligible with respect to the incident flux. The optical interference measurements monitored the ice film thickness versus H2O exposure time and were dependent on the refractive index, n, and the density, ρ,...

BACKGROUND AND PURPOSE: FUS-induced BBB opening is a promising technique for noninvasive and local delivery of drugs into the brain. Here we propose the novel use of a neuronavigation system to guide the FUS-induced BBB opening procedure and investigate its feasibility in vivo in large animals. MATERIALS AND METHODS: We developed an interface between the neuronavigator and FUS to allow guidance of the focal energy produced by the FUS transducer. The system was tested in 29 swine by more than 40 sonication procedures and evaluated by MR imaging. Gd-DTPA concentration was quantitated in vivo by MR imaging R1 relaxometry and compared with ICP-OES assay. Brain histology after FUS exposure was investigated using H&E and TUNEL staining. RESULTS: Neuronavigation could successfully guide the focal beam, with precision comparable to neurosurgical stereotactic procedures (2.3 ± 0.9 mm). A FUS pressure of 0.43 MPa resulted in consistent BBB opening. Neuronavigation-guided BBB opening increased Gd-DTPA deposition by up to 1.83 mmol/L (a 140% increase). MR relaxometry demonstrated high correlation with ICP-OES measurements ( r 2 = 0.822), suggesting that Gd-DTPA deposition can be directly measured by imaging. CONCLUSIONS: Neuronavigation provides sufficient precision for guiding FUS to temporally and locally open the BBB. Gd-DTPA deposition in the brain can be quantified by MR relaxometry, providing a potential tool for the in vivo quantification of therapeutic agents in CNS disease treatment. CE : contrast-enhanced FUS : focused sonography Gd-DTPA : gadolinium-diethylene-triamine pentaacetic acid ICP-OES : inductively coupled plasma optical emission spectroscopy MRgFUS : MR-guided FUS SI : signal intensity TUNEL : terminal deoxynucleotidyl transferase biotin-dUTP nick end-labeling