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Heating non-uniformity has been a major hurdle to numerous applications in microwave heating. The exposure to a non-uniform field is a well-known cause for this difficulty. There are, however, some much less-understood causes, which are inherent in nature in that they persist even in a perfectly uniform field. The current study addresses two such causes in water heating. The first one concerns the effects of field shielding by microwave-induced polarization charges, and the second one on the effects of microwave resonances in water.

The dimer under study is a dielectric structure formed of two identical sub-units. Dimer interactions with electromagnetic waves are widely studied in connection with electromagnetic properties of complex systems. The dimer in the form of two closely spaced grapes is also a subject of high public interest because its gap region sparks curiously in a household microwave oven. A recent paper presented the first scientific interpretation of this long-standing puzzle. It attributed the sparking phenomenon to an electromagnetic hotspot in the gap created by electromagnetic resonances in the dimer. This study has opened up a fertile ground for further research as well as motivating the current study on an independent mechanism. Our simulation and experimental results consistently point to an electrical origin for the sparks. The triggering mechanism is a two to three orders-of-magnitude buildup of localized electric field in the narrow gap, which results from the mutual enhancement of polarization charges on opposite sides of the gap. Consequently, sparks are observed at the frequency of 27 MHz, at which no electromagnetic resonance in the dimer is possible. Results also indicate a broad frequency range of the electrical mechanism, which persists even when the dimer is in strong electromagnetic resonance with the first few higher-order modes. These quantitative characterizations of basic dimer properties, in particular the broad frequency range of the polarization-charge enhancement effect, may be helpful for the understanding of collective behavior of multi-particle systems under electromagnetic radiations.

Through silicon via (TSV) is the key technology used in 2.5-D and 3-D packaging. Evaluating the reliability of products using this new technology has been challenging because of complex environmental factors. The aim of this paper was to design and implement a systematic reliability experiment to test self-designed TSV samples under the combinations of several different environmental variables. The Weibull distribution model was used to extract parameters from the experimental data for the statistical evaluation of TSV reliability. After analyzing the Weibull parameters, the environmental stresses that accelerate TSV unreliability were identified and compared, and a simple empirical unreliability equation was proposed. In addition, we observed that using a power law was an effective mean on making TSV reliability curve fittings. Failure analyses by optical microscopy, scanning electron microscopy, and energy dispersive spectrometer were finally reported.

Summary What is known and Objective: Spontaneous Adverse Drug Reaction Reporting Systems (ADRRS) provide early warnings or ‘signals’ for adverse drug reactions (ADRs). Our aim was to survey reports of ADRs made through our teaching-hospital-based pharmacovigilance system to identify the drugs most commonly associated with allergies and the types of immunological reactions reported. Methods: Adverse drug reactions records were retrieved from our network-based electronic notification system. Results and Discussion: Four hundred and seventy four reports of adverse drug effects were studied. 37·3% of the reactions were immune-mediated drug hypersensitivity reactions. True drug hypersensitivity reactions involving IgE-mediated drug allergies accounted for 15% of all reactions. Of the drug hypersensitivity reactions, more than half (67%) were morbilliform skin eruptions, whereas cases of urticaria accounted for 20%. Antibiotics (33% of cases) were the most commonly reported drug allergies, followed by non-steroidal anti-inflammatory drugs (13%) and anti-epileptic agents (10%). What is new and Conclusions: A hospital-based ADR reporting system can generate useful data. In our study, antibiotics accounted for the majority of drug allergies, particularly anaphylactic reactions. More cases of drug allergies were owing to cephalosporin allergies than penicillins. Anti-epileptic agents caused most of the severe drug hypersensitivity syndromes.

Solvent extraction of molybdenum and tungsten as homologues of Sg with α‐benzoinoxime from HCl solutions has been investigated. The extraction equilibration was achieved at 20s for Mo and W. Molybdenum was almost quantitatively extracted from 0.001 to 4 M HCl solutions, and the extraction yields decreased at higher and lower acid concentrations due to the formation of anionic oxychloride complex and anionic species MO4 2−, respectively. The extraction yield of W was lower than that of Mo during the whole range of acid concentration. The composition of the extracted species was determined by using the slope method in present experiment. The elemental analysis, IR and 1H NMR spectra of the extracted species suggest that the extracted complex contain one MoO2 2+ or WO2 2+ groups bonded with two α‐benzoinoxime molecules.

Background Nausea and vomiting occurs in gastroparesis due to diabetes mellitus or unknown causes. The aim of this study was to compare (i) pyloric distensibility to pyloric manometric pressure in patients with nausea and vomiting and (ii) to correlate distensibility with delays in gastric emptying. Methods Sleeve manometry and EndoFLIP were performed sequentially during the same endoscopy on 114 patients with nausea and vomiting (47 with diabetes mellitus and 67 with idiopathic cause) after a standardized gastric emptying study. The sleeve manometer was positioned fluoroscopically, and the EndoFLIP was placed endoscopically. Manometric pressure using a water-perfused catheter and distensibility using an EndoFLIP filled with 40 cc of saline were measured from the pylorus. Key Results The basal pyloric pressure was elevated (>10 mmHg) in 34 patients and was normal in 80 patients. The basal and peak pressures were similar in patient with normal and delayed gastric emptying (p > 0.05). There was a significant decrease in distensibility (8.0 ± 1.0 mm2/mmHg) in patients with gastric retention (>20% at 4 h) compared with patients (12.4 ± 1.4 mm2/mmHg) (p < 0.01) with normal gastric retention (

Stimulated emission from single ZnO tetrapod nanowires was studied by time-resolved photoluminescence (TRPL) spectroscopy. The samples were excited by a 300 fs pulse and the emission spectra collected as a function of time. The spectra exhibit a change in the position and the shape of the emission peak with time. The time evolution of the emission spectra was studied for different pump excitation fluences. The spectra exhibited a blue shift with increasing pump fluence, while for all pump fluences a red shift of the peaks with time was obtained. Possible reasons for the observed behaviour are discussed.

By observing experimentally obtained photoelastic fringe patterns and applying classical solutions for an infinite plate containing a circular hole under remote tension and the modified Hertz contact theory, a replaced superposition method is proposed. In this paper we use this method to investigate the state of stress around a near-surface circular hole in a semi-infinite plate under a concentrated load. The well-matched conditions between the reconstructed and experimental photoelastic fringe patterns indicate the applicability of the proposed method.

Xenotransplantation of pig organs and tissues to humans involves a risk of infection by porcine endogenous retrovirus (PERV). This investigation examined potential transmission of PERV by using an in vitro culture system and the in vivo nude-mouse model to assess the safety of a bioartificial skin composed of porcine matrix. Polymerase chain reactions for the DNA and RNA of PERV gag and pol sequences were used to survey PERV infection. An in vitro culture system, artificial skin composed of porcine matrix, was incubated in DKSF medium for 32 days, and the presence of PERV was determined by sampling every other day. The blood of 12 nude mice was screened on days 3, 14, and 21 for PERV, after the mice had received three different skin grafts. Tissue biopsy did not yield evidence of PERV DNA integration or mRNA expression in the nude-mouse model. These results suggest that porcine dermal matrix (PDM), living dermal equivalent (LDE), and living skin equivalent (LSE) do not produce infectious PERV in in vitro culture assays. Which supports evidence showing no PERV virus transmission in in vivo nude-mouse recipients.

Through Silicon Via (TSV) is the key technology for the 2.5D and 3D packaging, but reliability evaluations on the new technology products are limited because of the complexity of the environmental issues. To this end, reliability experiments on self-design TSV samples under combinations of several different environmental variables were proposed and performed in this study. The Weibull distribution model was next employed for reliability analyses and the parameters for each of the experimental results were extracted. After analyzing the Weibull parameters, factors that accelerate TSV unreliability are compared with discussions. This paper finally presents failure analyses through OM/SEM observations.

Autoantibodies associated with herpes gestationis (HG), a pregnancy-associated autoimmune skin disease, target the hemidesmosomal protein BP180. It was shown that the major noncollagenous stretch of the BP180 ectodomain (NC16A) harbors epitopes recognized by HG sera. Furthermore, Abs reactive with the homologous domain of murine BP180 are known to trigger a cutaneous blistering disease in mice by passive transfer experiments. The present study was aimed at characterizing the T cell responses and specificities of autoantibodies from two HG patients. Using immunoblotting and T cell proliferation assays, we have identified a 14-amino-acid stretch of the BP180 ectodomain (MCW-1; aa 507–520) that is recognized by both T cells and autoantibodies produced by the HG patients. The neonate born to one of these HG patients showed no signs of skin disease and had no detectable T cell response to the BP180 Ag, but did have a low titer of circulating anti-BP180 autoantibodies, presumably of maternal origin. BP180-specific T cell lines and clones developed from an HG patient specifically reacted with the MCW-1 epitope. The proliferative responses of these clones were restricted to HLA-DR, but not -DQ or -DP. These Ag-specific T cells expressed α/β TCRs and a CD4 memory T cell phenotype and secreted IFN-γ and IL-2, but not IL-4 or IL-6, suggesting that they are Th1-type lymphocytes. Further characterization of these Ag-specific T cells and autoantibodies will aid in elucidating the autoimmune mechanism(s) leading to the development of HG.

Interactions between select microorganisms and heavy crude oils in which the microorganisms have been introduced under controlled conditions proceed via a complex set of multiple biochemical and chemical reactions. Extensive studies in this laboratory have shown that such reactions are not random and differ from those involved in biodegradation of oils and follow distinct trends which can be categorized by means of characteristic chemical markers. These markers include mass spectrometric fragmentation patterns of light and heavy hydrocarbons, heterocyclic, organometallic compounds, trace metals, and the contents of heteroatoms. Bioconversion of heavy crude oils depends on the distribution of polar compounds containing nitrogen (N), sulfur (S), oxygen (O), and trace metals. The overall effects of induced biochemical reactions are a significant lowering (24-40%) of the N, S, O, and trace metal contents. Concurrently, there is also a redistribution of hydrocarbons (HC). The reactions are both biocatalyst and crude oil dependent and, in terms of chemical mechanisms, appear to involve the asphaltene and the associated polar fractions. Recent studies dealing with biochemical reactions in heavy crudes will be discussed.

This research sought to integrate C. S. Dweck and E. L. Leggett's (1988) model with attribution theory. Three studies tested the hypothesis that theories of intelligence—the belief that intelligence is malleable (incremental theory) versus fixed (entity theory)—would predict (and create) effort versus ability attributions, which would then mediate mastery-oriented coping. Study 1 revealed that, when given negative feedback, incremental theorists were more likely than entity theorists to attribute to effort. Studies 2 and 3 showed that incremental theorists were more likely than entity theorists to take remedial action if performance was unsatisfactory. Study 3, in which an entity or incremental theory was induced, showed that incremental theorists' remedial action was mediated by their effort attributions. These results suggest that implicit theories create the meaning framework in which attributions occur and are important for understanding motivation.

The responses of a cracked half-space subjected to an antiplane shear impact on the surface of the half-space are investigated in time as well as in frequency domains. Both surface-breaking and sub-surface cracks are considered. The problem in frequency domain is solved by a combined boundary integral and finite element approach. The finite element method is used for the near-field, while the boundary integral representation is used for the far-field. The response in time domain is calculated by using fast Fourier transform. The surface displacements, crack opening displacements and dynamic stress intensity factors are presented to show the significant effects of the cracks. The interaction of the impact waves and the crack can be clearly observed and understood from the numerical results in this paper. Some spectral amplitudes display regular peaks which indicate the existence of resonance phenomena that are associated with the characteristics of the crack. The location, length and depth of the crack can be easily detected by means of surface responses.

This paper investigates the oxidation kinetics of asphalt generic fractions and the contribution of each individual fraction to the oxidation of the whole asphalt. Polar aromatic (PA) and naphthene aromatic (NA) fractions of five Strategic Highway Research Program (SHRP) core asphalts (AAA-1, AAD-1, AAF-1, AAG-1 and AAM-1) were prepared and aged at multiple conditions to obtain their kinetic parameters. Aromatics/saturates/asphaltenes blends of four of the five asphalts were also aged to deduce the influence of saturates and asphaltenes. Carbonyl growth in the PA and NA fractions as a result of oxidation follows a similar profile as the whole asphalts. The kinetic parameters of the NA fractions occur in two groups, one with high reaction order and activation energy, and the other with low values of each. The kinetic parameters of the PA fractions all fall into the low-values group. Although the PA fraction is the most reactive portion in an asphalt, its kinetic parameters (reaction order and acti...

The scattering of antiplane impact waves by cracks in a layered elastic solid is investigated by using a hybrid method which combines the finite element discretization of the near field with the boundary integral representation of the far field outside a contour completely enclosing the crack. This combined method leads to a set of linear unsymmetric complex equations which are stored in a compacted data structure and solved to obtain response spectrum by biconjugate gradient methods. The transient response is then obtained by FFT. Numerical results are presented for the surface displacements, crack opening displacements, and stress intensity factors to show the effects of the crack and the interface. Moreover, the propagation of reflected, diffracted, and direct impact waves can be clearly observed.

The purpose of this case-control study is to estimate the risks of Stevens-Johnson syndrome or toxic epidermal necrolysis associated with the use of specific drugs. The suspected cases were identified from the computerized hospital discharge file. We calculated crude relative risks and adjusted them for confounding by multivariate analysis. The analysis was based on 35 cases and 105 controls. This study showed that the use of carbamazepine, phenytoin and allopurinol is most associated with the risks in the oriental population.

195Pt-,139La- and11B-NMR have been investigated in quaternary RM2B2C (R=Y, La, Th and M=Ni, Pd, Pt). The electric quadrupole frequency of139La changes more than 5 times in magnitude from M=Ni to Pt, indicating that the hybridization of La-5d and d-electrons of M-element changes largely. The analysis of11B and139La spectra shows also the large change of the magnetic anisotropy with R and M element, i.e., χII c>χII ab in LaNi2B2C, but χII c>χII ab YNi2B2C.The data of T1T and K of195Pt and11B are consistent with the band effects and with no evidence of strong antiferromagnetic correlation effects.

Unsteady, axisymmetric transport of mass, momentum, energy, species, and magnetic field intensity with a mushy-zone phase change in workpieces and temperature, and magnetic fields in electrodes during resistance spot welding, are systematically investigated. Electromagnetic force, joule heat, heat generation at the electrode–workpiece interface and faying surface between workpieces, different properties between phases, and geometries of electrodes are taken into account. The computed results show consistencies with observed nugget growth, electrical current, and temperature fields. The effects of the face radius and cone angle of the electrode, parameters governing welding current, electrical contact resistance, magnetic Prandtl number, electrical conductivity ratio, and workpiece thickness on transport phenomena are clearly provided.

The chemical and physical properties of the cylindrical rods SiCx (x = 0.3 − 1.2) produced by laser pyrolysis of Si(CH3)2Cl2 were studied by various methods. Although their outer features appeared smooth and uniform, they consisted of tiny melts with a size of about 20 μm. The X-ray diffraction patterns indicated a polycrystalline structure. The elemental analysis showed that the major components were Si and C with atomic ratios C/Si of 0.3 and 1.2 grown by 1 and 4 W of laser radiation in Si(CH3)2Cl2 at 135 torr, respectively. Auger spectra showed similar C/Si ratios. Furthermore, Auger depth profile spectra revealed some detailed information on the composition distribution perpendicular to the axis of the cylindrical rods. The electrical resistivity and its temperature dependence were measured as well as its hardness. It had a photovoltaic effect. It should be emphasized that samples with the desired outer features, composition and physical properties could be grown by controlling the growth conditions properly—the laser power and the pressure of Si(CH3)2Cl2.

This paper presents an algorithm for constructing a 3D workpiece in CSG (constructive solid geometry) representation from a single 2D isometric drawing. Currently, the concerned workpieces are limited to simple rectilinear polyhedra where any two faces or edges are either parallel or perpendicular to each other, however, the shape of constructed workpiece can further be modified by the application of wireframe-based approach of variational geometry. Compared to previous relevant work, the proposed algorithm is distinguished by its capability to deal with degenerate 2D line drawings; that is, problems where two distinct edges are projected on to one line can be solved.

To evaluate whether homeostasis model assessment and high-sensitivity C-reactive protein improve the prediction of isolated post-load hyperglycaemia.The subjects were 1458 adults without self-reported diabetes recruited between 2006 and 2010. Isolated post-load hyperglycaemia was defined as fasting plasma glucose7 mmol/l and 2-h post-load plasma glucose ≥ 11.1 mmol/l. Risk scores of isolated post-load hyperglycaemia were constructed by multivariate logistic regression. An independent group (n = 154) was enrolled from 2010 to 2011 to validate the models' performance.One hundred and twenty-three subjects (8.28%) were newly diagnosed as having diabetes mellitus. Among those with undiagnosed diabetes, 64 subjects (52%) had isolated post-load hyperglycaemia. Subjects with isolated post-load hyperglycaemia were older, more centrally obese and had higher blood pressure, HbA(1c), fasting plasma glucose, triglycerides, LDL cholesterol, high-sensitivity C-reactive protein and homeostasis model assessment of insulin resistance and lower homeostasis model assessment of β-cell function than those without diabetes. The risk scores included age, gender, BMI, homeostasis model assessment, high-sensitivity C-reactive protein and HbA(1c). The full model had high sensitivity (84%) and specificity (87%) and area under the receiver operating characteristic curve (0.91), with a cut-off point of 23.81; validation in an independent data set showed 88% sensitivity, 77% specificity and an area under curve of 0.89.Over half of those with undiagnosed diabetes had isolated post-load hyperglycaemia. Homeostasis model assessment and high-sensitivity C-reactive protein are useful to identify subjects with isolated post-load hyperglycaemia, with improved performance over fasting plasma glucose or HbA(1c) alone.

Spontaneous Adverse Drug Reaction Reporting Systems (ADRRS) provide early warnings or 'signals' for adverse drug reactions (ADRs). Our aim was to survey reports of ADRs made through our teaching-hospital-based pharmacovigilance system to identify the drugs most commonly associated with allergies and the types of immunological reactions reported.Adverse drug reactions records were retrieved from our network-based electronic notification system.Four hundred and seventy four reports of adverse drug effects were studied. 37.3% of the reactions were immune-mediated drug hypersensitivity reactions. True drug hypersensitivity reactions involving IgE-mediated drug allergies accounted for 15% of all reactions. Of the drug hypersensitivity reactions, more than half (67%) were morbilliform skin eruptions, whereas cases of urticaria accounted for 20%. Antibiotics (33% of cases) were the most commonly reported drug allergies, followed by non-steroidal anti-inflammatory drugs (13%) and anti-epileptic agents (10%).A hospital-based ADR reporting system can generate useful data. In our study, antibiotics accounted for the majority of drug allergies, particularly anaphylactic reactions. More cases of drug allergies were owing to cephalosporin allergies than penicillins. Anti-epileptic agents caused most of the severe drug hypersensitivity syndromes.

The article is about the development center for biotechnology, a non profit biotech research and development organization of about 300 employees.

Rapid thermal processing with a controlled cooling ramp as a postoxidation annealing in nitrogen is of considerable influence on the quality of thin (6 nm) thermal oxides. We studied how the annealing condition affected the electrical characteristics of the dielectrics, the charge‐trapping properties, the gate voltage shift ΔVG, the flat band voltage shift ΔVFB, the increase of midgap interface state density ΔDitm under high field stress, the charge to breakdown, and the breakdown field. We found that controlled cooling after oxidation improved the interface between silicon and silicon dioxide. The postoxidation annealing in nitrogen reduced the fixed charge in oxides. The above measurements were correlated.

Tl-201 myocardial scintigraphy (Tl study) tends to be attenuated by soft tissues (such as the diaphragm) due to its low energy emission. 99mTc-sestamibi (2-methoxy isobutyl isonitrile) is a relatively new agent with a higher energy emission and this characteristic accounts for the higher quality of 99mTc-sestamibi images. The purpose of this study is to evaluate the ability of 99mTc-sestamibi in alleviating the inferior attenuation of Tl studies. 99mTc-sestamibi SPECT myocardial scintigraphy was performed on 13 patients with inferior wall perfusion defects as determined by Tl study (but with normal coronary artery as evidenced by cardiac catheterization). All patients underwent Tl SPECT study using a standard procedure. Same-day protocol (rest-stress sequence) was used for 99mTc-sestamibi SPECT imaging. All images were analyzed by two independent observers. The results of our study reveal that 99mTc-sestamibi produced better images. The inferior wall perfusion defects in the T1 study were noted in one case only (1/13) in the 99mTc-sestamibi study. Our study suggests that 99mTc-sestamibi can remarkably reduce the inferior attenuation of Tl study.

Anomalous interface states were caused by post‐oxide rapid thermal annealing in an n+ polycrystalline silicon metal‐oxide‐semiconductor capacitor. These anomalous interface states have been investigated using high/low frequency capacitance/gate voltage (C/V) measurements. An additional annealing process (450 °C, 30 min in 90% N2/10% H2 mixed gas) was found to improve the anomalous interface states. The improved results were identified using a constant current injection stress test.

A 42-year-old man with a history of diabetes mellitus presented with fever and productive cough for 1 week. Chest radiography revealed a large cavity lesion with an air-fluid level in the left upper lobe (Figure 1) suggesting a lung abscess. Sputum culture yielded Klebsiella pneumoniae. After third-generation cephalosporin antibiotics treatment for 1 week, the follow-up chest radiography showed improvement. However, pustular skin lesions developed on the fingers (Figure 2), and aspirated pus also yielded K. pneumoniae. Septic emboli were considered but abdominal computed tomography, colonoscopy and echocardiogram all showed no abnormal findings. Following antibiotics treatment, the pustular skin lesions became encrusted (Figure 3) and the patient recovered.

The qualitative study of the interaction between planar shock wave and a hemi-sphere-cylinder model with and without corona discharge plasma from its copper head have been done in the shock tube facility of Institute of Aeronautics and Astronautics in National Cheng-Kung University. With the incident Mach number of 1.3-1.69, the shock wave reflected on the model with regular reflection and transition to Mach reflection have been observed for model without corona discharge plasma. With the corona discharge plasma effect from the model copper head, the similar shock wave patterns were observed. However, a widening thickness of the shock and a shortening of the length of the Mach stem were observed and the location of the triple point is closed to the model surface. The curvature of the reflected shock wave is being increased. From the measured pressure signal of the relative strength of the shock reflection from the model head, a longer time is need and the measured signal strength is much smaller. It has clearly shown that under the effect of corona discharge plasma the shock reflection from the model head with a smaller speed and a much weaker strength. This is a strong indication that the corona discharge plasma can decrease the strength of shock wave properly.

The liquid-liquid extraction behavior of shortlived molybdenum and tungsten isotopes from HCl and HNO 3 as well as HF/HNO 3 acid media was studied using the α-benzoinoxime/chloroform system. The goal of the present experiments was to find an extraction system with a high selectivity for the group 6 elements in the periodic table which is suitable for the study the solution chemistry of seaborgium (Z = 106). It was found that Mo and W are both effectively extracted using α-benzoinoxime as an extractant and the maximum extraction yield is 100% and 94% for Mo and W, respectively. Ions of MO 2 2+ (M = Mo, W) exist in HCl between the concentration range of 0.1―3 M and can be extracted quantitatively into the organic phase. The decrease of extraction yields at lower or higher acid concentration is due to the formation of anionic species MO 4 2― or MO 2 Cl 3 ― . The extraction behavior of Mo and W in HNO 3 solution is similar to that in HCl solution. In HNO 3 /HF mixed acid solutions, due to the formation of MO 2 F 3 ― a decrease of extraction yield at higher HF concentration, similar to the case of HCl is observed. The extraction equilibrium is reached within 10―30 s, which means the extraction kinetics of α-benzoinoxime/chloroform extraction system is fast enough for the study of the isotope 265 Sg. The extraction behavior of molybdenum and tungsten shows a distinct difference in the range of 0.05 to 0.2 M HF with 1 M HNO 3 . This shows that differences in the complexation with fluoride ion exist in Mo and W. This study focuses on the investigation of the tendency of group 6 element for complexation with fluoride ion.

The multiphoton dissociation processes of acetylene via a two‐photon resonant predissociative state, v=0 of 1Σ+g, have been studied by three techniques: time‐resolved photofragment excitation spectroscopy (TRPFES), laser‐induced fluorescence (LIF) of the C2 fragments, and dispersed emission. We found that the major dissociation products are H atoms, H2 molecules, and C2 molecules in the X 1Σ+g, a 3Πu and A 1Πu states; among the latter, C2 X 1Σ+g molecules are formed by a sequential bond–rupture mechanism whereas some C2 in a 3Πu is formed by a concerted two‐bond fission process. Other, minor dissociation channels due to three‐photon processes, such as C2(d 3Πg)+2H(2S(1)/(2)), C2(d 3Πg)+H2(X 1Σ+g), C2(C 1Πg)+H2(X), C2(e 3Πg)+H2(X), and C2(D 1Σ+u)+H2(X), were also detected. In the 2+1 concerted dissociation yielding C2(C 1Πg)+H2(X), a long‐lived intermediate C2H2, likely a cis isomer or other conformer in which the hydrogen atoms are relatively close to each other, was revealed by TRPFES; its zero‐pressure ...

CyberKnife stereotactic radiosurgery (CKSRS) has been proved effective in treating intra-cranial lesions. To treat acoustic neuroma (AN) patients with or without neurofibromatosis Type 2 (NF2) associations, the functional preservation of hearing, trigeminal nerve, and facial nerve are important. Twenty-one patients were treated with hypofractionated CKSRS. Fourteen non-NF2 and seven NF2 patients were enrolled. Cranial nerve function, audiograms, and magnetic resonance images (MRI) were monitored. Mean follow-up was 15 month. Tumors with volumes ranging from 0.13 to 24.8 cm3 (mean 5.4 cm3) were irradiated with the marginal dose 1800-2000 cGy/3 fractions. Tumors were treated with an 80 to 89% isodose line (mean 83%) and mean 97.9% tumor coverage. Two patients experienced hearing deterioration (16.7%) in the non-NF2 group, and 3 patients (50%) in the NF2 group. No facial or trigeminal dysfunction, brain stem toxicity, or cerebellar edema occurred. Tumor regression was seen in 9 patients (43%) and stable in 12 patients (57%). 100% tumor control rate was achieved. Hypofractionated CKSRS was not only effective in tumor control but also excellent in hearing preservation for non-NF2 AN. But for NF2 patients, although the tumor control was remarkable, hearing preservation was modest as in non-NF2 patients.

Multi-GHz measurements of signal propagation and crosstalk are reported for small, somewhat resistive, copper microstrips (20-30 μm width and 2-3 μm thickness) that are embedded in polyimide dielectric and fabricated on a silicon substrate. The transmission, reflection, signal velocity, and crosstalk on 50-Ω terminated microstrips are well behaved and, moreover, are well described by standard transmission line theory when resistive losses (corrected for the skin effect) are included.

Measurements of the second harmonic distortion in 1.3 mu m InGaAsP distributed feedback lasers are reported. At low modulation frequencies ( approximately 50 MHz), the second harmonic distortion exhibits a minimum at a certain bias current. The minimum, in general, is not observed at high modulation frequencies ( approximately 1 GHz). A model of the harmonic distortion, based on the equivalent electrical circuit of the laser, is presented to explain the observed behavior. The spatial hole burning effect in the active region introduces additional nonlinearity, its effects can be significant compared to that of the leakage path. >

Measurements are reported of the second‐harmonic distortion in 1.3‐μm InGaAsP distributed feedback lasers operating at different temperatures. A minimum of the second‐harmonic distortion exists at a particular bias current when the laser is operating at low temperature (10 °C). The minimum shifts to a higher bias current when the operating temperature is raised. At an even higher temperature, the minimum dissappears. A temperature‐dependent model of the second‐harmonic distortion, based on an equivalent circuit analysis, is presented to explain the experimental results.

Measured capacitance coefficients of parallel microstrip lines with widths between 10-20 mu m, spaces between 5-60 mu m, and dielectric thickness between 10-15 mu m on silicon substrates are reported. The experimental data are compared with results computed from a two-dimensional finite-element simulation program called WIRECAP. The comparison shows good agreement, with an accuracy of +or-5% for the total capacitance and not=20% for the coupling capacitance. WIRECAP is also shown to be in good agreement with other available simulation programs, such as the University of Arizona capacitance calculator (UAC) program. The measured near-end crosstalks are reported and it is shown that they can be accurately predicted by using the measured coupling capacitance. >

In ST-segment elevation acute myocardial infarction (STEMI), dislodgement of thrombus within the culprit artery during primary percutaneous coronary intervention (PCI) may cause distal embolisation and impaired myocardial reperfusion. Clinical results of thromboembolic protection strategies have been controversial. We conducted this study to investigate whether the benefit of thrombus removal is time dependent.Seventy-four STEMI patients within 12 h from onset were randomised to receive either primary PCI with initial thrombosuction (IT) or standard strategy. Results were analysed in subgroups according to the onset-to-lab time intervals (subgroup 1: 0-240 min, subgroup 2: 241-480 min and subgroup 3: 481-720 min).The primary end-points were improvements in thrombolysis in myocardial infarction flow (DeltaTIMI) and myocardial blush grade (DeltaMBG) postprocedure. Better DeltaTIMI (2.2 +/- 1.1 vs. 1.5 +/- 1.3, p = 0.014) and DeltaMBG (2.3 +/- 1.1 vs. 1.0 +/- 1.5, p0.001) were observed in IT patients, compared with standard PCI patients. In onset-to-lab time subgroup analysis, the difference between IT and standard PCI is significant only in subgroup 2 (DeltaTIMI 2.6 +/- 1.0 vs. 1.3 +/- 1.2, p = 0.007; DeltaMBG 2.6 +/- 0.9 vs. 1.0 +/- 1.1, p = 0.010), but not in the other two subgroups.This prospective randomised study shows that primary PCI with IT may improve epicardial flow and myocardial reperfusion in patients with STEMI, and this benefit is the most significant in patients treated within 4-8 h after symptom onset.

Syringomyelia is an uncommon disease that is caused most often by type I Chiari malformation, which develops in the hindbrain, and less frequently by other factors which are not limited to the hindbrain, including trauma, infection, or scoliosis. Idiopathic syringomyelia is rare. We present in this article a patient with idiopathic syringomyelia characterized by hypoesthesia and progressive weakness in the left lower limb. Decompression was attempted by means of laminectomy and a syringoarachnoid shunt. Motor, sensory, and bladder functions were monitored by the change in Japanese Orthopedic Association scores, which increased from 10 points preoperatively to 14 points 30 days postoperatively. This case demonstrates the effectiveness of surgical decompression in a patient with remarkable neurological deficit.

Heating of dielectric objects by radio frequency (RF) and microwaves has long been a method widely employed in scientific research and industrial applications. However, RF and microwave heating are often susceptible to an excessive temperature spread due to uneven energy deposition. The current study elucidates an important physical reason for this difficulty and proposes an effective remedy. Non-spherical samples are placed in an anechoic chamber, where it is irradiated by a traveling microwave wave with 99% intensity uniformity. Polarization charges induced on the samples tend to partially cancel the incident electric field and hence reduce the heating rate. The polarization-charge shielded heating rate is shown to be highly dependent on the sample's shape and its orientation relative to the wave electric field. For samples with a relatively high permittivity, the resultant uneven heating can become a major cause for the excessive temperature spread. It is also demonstrated that a circularly polarized wave, with its rapidly rotating electric field, can effectively even out the heating rate and hence the temperature spread.

Aim: To determine the acute and chronic vascular effects of endoscopic cyclophotocoagulation (ECP) versus trans-scleral cyclophotocoagulation (TCP) in a rabbit model. Methods: 20 rabbits underwent ECP in one eye and another 20 rabbits had unilateral TCP. Five treated eyes from each group underwent endoscopic fluorescein angiography (EFA) of the treated ciliary processes at each of the following time points: immediate, 1 day, 1 week, and 1 month. Five untreated rabbits were used as controls. The NIH Image software program was used to trace ciliary processes in order to determine their mean intensity, as a measure of their perfusion. Histopathology was also performed on eyes from each time point. Results: Immediately and 1 day after laser, both TCP and ECP eyes demonstrated severely reduced or non-existent blood flow in the areas of treatment. TCP treated processes essentially remained non-perfused at the 1 week and 1 month time points. ECP treated processes showed some reperfusion at 1 week and greater reperfusion by 1 month. Histopathology confirmed the overall greater vascular occlusion seen with TCP. Conclusions: Chronic poor perfusion of the ciliary body after TCP may account, in part, for its efficacy, as well as the significant complications including hypotony and phthisis. Late reperfusion of this region after ECP may provide some insight into the differences in efficacy and complication rates compared to TCP.

This paper describes a Spice-compatible circuit simulation model of submicron LDD MOS devices. It includes an enhanced model of our previous drain current characteristics (UNIMOS) and a new analytical substrate current model. For the drain current characteristics, new features of our previous model has been added for achieving good accuracy and convergency. In addition, the two-dimensional electric field distribution during impact ionization which has much more physical meaning is considered for developing the hot electron model. Thus, a new and accurate substrate current model is proposed based on the so called effactive electric field, instead of the conventional peak electric field concept used by the lucky-electron (LE) theory. Comparison of the modeled results with those of experiment shows excellent match for a wide range of device channel lengths and bias conditions.

The purpose of this case-control study is to estimate the risks of Stevens-Johnson syndrome or toxic epidermal necrolysis associated with the use of specific drugs. The suspected cases were identified from the computerized hospital discharge file. We calculated crude relative risks and adjusted them for confounding by multivariate analysis. The analysis was based on 35 cases and 105 controls. This study showed that the use of carbamazepine, phenytoin and allopurinol is most associated with the risks in the oriental population.

The gate-and-drain fully-overlap LATID (Large-Tilt-Angle Implanted Drain) structure has been proposed recently and been used in submicron MOS device design to suppress the spacer-induced degradation and improve the device current drivability. So far, none has been provided to study quantitatively the hot carrier effect for various device process conditions such as the implantation of n/sup -/ dosage and angle. A closed form expression of a new and accurate substrate current model is proposed based on the effective electric field concept by considering the overall (2D) electric field distribution within devices, which can be used to explain quantitatively and for predicting the substrate currents of LATID MOS devices. Its utilization in designing a hot carrier resistant device is demonstrated. >