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Accumulating evidence shows that genes that cause monogenic diseases also contribute to similar complex disease in the general population. We sought to determine whether the allelic variation in seven monogenic bone disease genes (CLCN7, TCIRGI, SOST, CA2, CSTK, TGFB1 and SLC26A2) contributes to osteoporosis/bone mineral density (BMD) variation in the normal Chinese population. We conducted a gene-wide tag SNP-based association study in 1243 Chinese subjects with low BMD (Z-scoresor = -1.28, equivalent to the lowest 10% of the population) and high BMD (Z-scoreor = +1.0). Twenty-two tag SNPs were selected and genotyped by using the high-throughput Sequenom genotyping platform. Allelic and haplotype association tests were conducted by Haploview and binary logistic regression analyses. The -9247 polymorphism rs1230399 in the upstream regulatory region of the sclerostin gene showed significant genotypic/allelic associations with spine, femoral neck, trochanter and total hip BMD (P=0.03-0.004). The T-allele of rs1230399 increased the risk of osteoporosis (OR=1.52, P=0.005). Computational analysis showed that rs1230399 is located at the core consensus recognition site of two cooperating transcription factors C/EBPalpha and FOXA1 that modulate estrogen receptor function. T--C polymorphism abolishes the binding of both C/EBPalpha and FOXA1 to the sclerostin gene. Our data suggest a mechanistic link between rs1230399 and BMD through estrogen ERalpha/FOXA1 signaling pathways driven by long-distance enhancers.

Phytophotodermatitis is a phototoxic dermatologic reaction that occurs with exposure to ultraviolet light after contact with certain plant chemicals. Recognition is vital to proper management and avoidance of unnecessary distress for patients. Sun-sensitizing compounds, known as furocoumarins, are found in many plants (limes, celery, and natural grasses) and are excited by ultraviolet A (UVA) irradiation. UVA irradiation induces covalent linkages of nuclear DNA resulting in cutaneous photosensitivity and vesicular skin damage while increasing melanin production. Delayed erythema, hyperpigmentation, and vesicle or bullae formation are hallmarks. Literature review reveals most cases occur during or after vacation in a sunny destination with exposure to citrus fruit or in children playing outdoors in the summer when furocoumarins are abundant. Hyperpigmented lesions typically appear on the hands or around the mouth. Overall incidence is unknown and there appears to be no predilection for race, although typically more easily recognized in the fair skinned. Of concern are the many cases where misdiagnosis of child abuse has occurred with unnecessary legal action taken and emotional distress for innocent families. Phytophotodermatitis is relatively common and easily diagnosed with awareness and a careful history. Accurate diagnosis avoids unnecessary concern by patients and potential misdiagnosis of abuse. Consider phytophotodermatitis when hyperpigmentation in bizarre streaks on sun-exposed areas with vesicles in a nondermatomal distribution is present. Presented is an illustrative case.

Copper (Cu)-matrix composites combine the high electrical and thermal conductivities of Cu with the enhanced wear resistance and strength of the reinforcement material, and are therefore widely used for electrical contact applications in a diverse range of fields. In the current study, tungsten-reinforced copper (W—Cu) composite powders are fabricated using a novel electroless Cu plating process in which the homogeneity of the powder mixture is improved via the use of an ultrasonic agitation technique. The volume content of the tungsten particle reinforcement in the composite specimens is 3, 6, and 12 per cent, respectively, and standard powder metallurgical techniques are then applied to produce the final composite powders. The mechanical and electrical properties of the composite powders are evaluated at room temperature and at temperatures ranging from 100 to 300 °C. Fracture surfaces of the composite samples are ana-lysed using scanning electron microscopy. The results show that the mechanical properties of the W—Cu composite samples are significantly better than those of pure Cu specimens, particularly at higher temperatures. Furthermore, the addition of 3 vol% W particles to the W—Cu composite is found to yield a reduction of not more than 2 per cent in the electrical conductivity of the composite sample compared to that of a pure Cu specimen. Overall, the results indicate that the optimal mechanical and electrical properties are obtained by mixing pure Cu powder with 3 vol% of Cu-plated W particles with a mean dimension of 1 μm.

Two approaches to synthesize silicon-based catalytic structures that aim at capturing the properties and functionalities of natural enzymes are described in this brief review: unit-by-unit synthesis of macromolecular units and templating/imprinting synthesis of nano-cages. The unit-by-unit approach mimics the peptide synthesis method, offers atomic control of the structure, but is inefficient in synthesizing large structures such as nanocages. The templating/imprinting method is more suitable for nanocages at the sacrifice of atomic control, and the nanocages obtained are shown to possess properties exhibited by enzyme cavities.

The reduction of NO, at 185 °C on Pd supported on Ti-pillared clay was studied using H 2 and CO generated by reforming of ethylene glycol (EG) over a Na-Pt/γ-Al 2 O 3 catalyst. It was found that for a stream containing 490 ppm NO, 5.8% Ο 2 , and 2.9% H 2 O, at a space velocity of ∼24,000 h -1 , a stable NO x conversion of ∼55% was obtained when a stream of 1.36% EG was reformed under a condition that the EG conversion was complete and sufficient H 2 and CO was produced. However, if the EG conversion was incomplete, the unreacted EG deactivated the deNO x catalyst, possibly by coking, that could not be regenerated by O 2 treatment at reaction temperature. H 2 O suppressed the deNO x activity, but the effect was reversible and the activity could be recovered after removal of H 2 O. The deNO x activity was found to be higher on catalysts containing more highly dispersed Pd.

Lithographic techniques were used to develop patterned silicone rubber membranes that provide 15 microm high microchannels for artificial lungs. Two types of devices were fabricated as a proof-of-concept: one has a series of parallel, straight, open rectangular channels that are each 300 microm wide, separated by 200-microm walls, and 3-mm long and the other is a wide rectangular channel with support posts, also 3- mm long. Experiments with 30% hematocrit, venous, bovine blood showed average oxygen fluxes ranging from 11 x 10(-7) moles/(min x cm(2)) at a residence time of 0.04 sec to 6.5 x 10(-7) moles/(min x cm(2)) at a residence time of 0.20 sec. The average oxygen flux vs. residence time, which is due to transverse molecular diffusion, follows the same relation for all membranes tested. The corresponding increase in hemoglobin saturation ranged from 9% at the residence time of 0.04 sec to 24% at the residence time of 0.20 sec. The support-post channel membranes are attractive for designers because they can be arbitrarily wide and would be less prone to blockage.

Whereas cooperative effect in catalysis, in which multiple chemical interactions participate cooperatively to achieve significant enhancement in catalytic activity and/or selectivity, is common in enzymatic reactions, it has been sparingly employed in heterogeneous catalytic systems. Here, some recent literature examples of abiotic catalysis, with emphasis on heterogeneous systems, that employ cooperation between acid and base and two metal centers are briefly described to demonstrate the principles involved. Since effective cooperation places strict demand on the positions of the different functional groups, new synthetic methods and strategies are needed to design and construct structures useful for cooperative catalysis. Recent progress in our laboratory in synthesizing new nanocage structures that possess molecular-size cavities, atomic layer thick, porous shells with internal functional groups is described. These recent developments suggest possibilities of new catalytic transformations that have not been attempted before. This is illustrated with two speculative examples utilizing cooperative catalysis: oxidative hydrolytic desulfurization and terminal carbon activation of hydrocarbon molecules.

The effect of halide poisoning of Au/TiO{sub 2} catalysts in low temperature CO oxidation was investigated using bromide as the poison and a combination of X-ray absorption spectroscopy (XANES and EXAFS), quantitative CO adsorption, and catalytic measurements. It was found that halide prevented full reduction of cationic Au by displacing oxyhydroxy ligands and remaining bound to Au during low temperature reduction, causing a reduction in catalytic activity. On reduced Au samples, bromide (likely as NaBr molecule) was preferentially adsorbed on Au and not on TiO{sub 2}, and suppressed both the adsorption of CO and the catalytic activity. At low Br contents, each adsorbed Br suppressed adsorption of three CO, suggesting that Br was adsorbed on three-fold sites but the effect decreased with increasing Br content possibly due to crowding of adsorbed Br. When 5--10% of the Au was bound to Br, the catalytic activity was completely blocked, although {approx}35% of the original CO adsorption capacity remained. The data suggest that not all CO adsorption sites are catalytic active sites, and are consistent with the perimeter Au atoms at/near the particle-support interface (perimeter) being active sites.

The epoxidation of 1-hexene with titanium silicalite-1 (TS-1) catalyst was investigated to gain insight into the effect of the solvent on the observed reactivity. Three different solvents were examined: methanol, acetonitrile, and acetone. Kinetic data were obtained from batch reaction experiments, with an emphasis placed on gathering more accurate initial rates than those reported in the literature. The dependencies of the rates on the concentrations of 1-hexene, water, and hydrogen peroxide were determined. The adsorption behavior of 1-hexene in TS-1 in the three different solvents was determined independently by batch sorption experiments. Results showed that the solvent has a significant effect on the adsorption of 1-hexene, and hence on the reaction kinetics. Kinetic modeling incorporating experimental and simulated quaternary adsorption isotherms to describe quasi-equilibrated steps revealed that the differences in the observed reaction kinetics may be attributed mostly, but not entirely, to differences of the partitioning of 1-hexene between the bulk and intraporous phases among the three different solvents.

Summary This study analyses the trend in hip fracture incidence in Southern Chinese in Hong Kong. The results show that the age-adjusted incidence has stabilized in recent years. Among subjects aged 50–59 years, a declining fracture rate is observed. Increasing awareness and a healthier ageing population could partly explain this improvement.

Ethylene glycol (EG) reforming was investigated as a method to generate H2 and CO reductants for low-temperature lean NOx reduction. Stable production of H2 was obtained at 230 °C over a Pt/Al2O3 catalyst using a feed consisting of 2−5% O2 and >2.2% EG. The presence of H2O in the feed enhanced H2 production, as did Na modification of the catalyst. Water gas shift was determined not to contribute significantly to H2 production during EG reforming.

An efficient synthetic strategy for immolative carbamate dendrons and dendrimers is described that requires no protection/deprotection in the convergent growth step. 1,3-Diamino-2-propanol was used as AB 2 building block and 4-nitrophenyl chloroformate as carbamate forming reagent. The method was demonstrated with a G3-dendron. A combination of convergent and divergent growth method was used to couple G2-dendrons to a G2-core or G3-dendrons to a tetrahedral G1-core with amine functional groups to form a spherical carbamate dendrimer (G4) possessing an olefinic periphery.

Seamless tubing of C-250 maraging steel manufactured by the flow forming technique was joined by the electron beam welding process. Various post-welding heat treatments were conducted to improve the overall mechanical properties of the welded tubing. For the 480°C/6 h/air cooling post-weld aging treated maraging steel, a significant increment of 11% reversion austenite was present in the weld metal. Only the tensile strength of this aging treated metal met the required specification while its percentage elongation reached only 50% of the specification, attaining only 35% of the strength of the parent metal. For the post-welded solution + aging treated maraging steel, only the yield strength met the specification. Moreover, a significant amount of reversion austenite pools was also present at the grain boundaries of the material located at the weld metal. Although the homogenisation treatment could improve the hardness of the weld metal, it failed to have the tensile strength of the steel met the s...

This paper reviews the physics and technology of wave-particle-interaction experiments in the ion cyclotron range of frequencies (ICRF) and the lower hybrid (LH) range of frequencies (LHRF) on the ...

Background and aims Hepatocellular carcinoma (HCC) is a cancer of rising incidence in the UK. The aim of this study was to compare the Okuda, Cancer of the Liver Italian Program (CLIP), and Barcelona Clinic Liver Cancer (BCLC) classifications as predictors of survival in UK patients with HCC. Methods Data were analysed from a prospective database maintained in a specialist hepatobiliary unit from 1998 to 2003. Each system was assessed for its discriminatory power, monotonicity of gradient, and independent contribution to prediction of mortality status based on a multivariate model. Results One hundred and two patients (77 males, 25 females) were identified with a median age of 65 (range, 14–87) years. The overall median survival time was 13 months and the one- and five-year survival rates were 52.9% (95% CI: 43.2%, 62.6%) and 35.3% (95% CI: 26.0%, 44.6%), respectively. All three classification systems had the capacity to differentiate between patient survival times across different stages. The Okuda system was superior in overall discriminatory power and in strength of monotonicity. The BCLC system, however, made the highest independent contribution of all three systems in predicting survival in the Cox regression model. Conclusions All three classification systems were effective in predicting survival for patients with HCC in a UK population.

Background Ultrasonography (USG) and technetium-99m sestamibi (MIBI) scintigraphy are commonly used imaging modalities in the era of minimally invasive parathyroidectomy (MIP) for primary hyperparathyroidism (pHPT). However, their relative importance and actual contribution to MIP have not been prospectively assessed. Methods A total of 100 consecutive pHPT patients planning for MIP were recruited. Both USG and MIBI findings were correlated with intraoperative findings and postoperative outcome. Clinicopathologic factors were examined for potential association with a correct localizing result. Results Thirty men and 70 women (age range 13 to 93 years [median 55.5]) were included in the study. The final pathology included 98 patients with solitary adenoma and 2 patients with multiglandular disease. The sensitivities, accuracies, and positive predicted values for USG and MIBI alone were 57% vs 89%, 56% vs 85%, and 97% vs 94%, respectively. Correctly localized adenomas were significantly heavier than incorrectly localized ones. Conclusions MIBI is preferred over USG in pHPT patients planning for MIP. Weight of adenoma appeared to be the only clinicopathologic factor determining localization accuracy.

Background: We have previously shown that neonates in profound cardiogenic shock due to severe Ebstein’s anomaly can be successfully salvaged with fenestrated right ventricular (RV) exclusion and systemic to pulmonary shunt (modified Starnes procedure). The long-term outcome of single ventricle management in these patients is not known. Methods: We retrospectively reviewed the records of 26 patients who underwent neonatal Starnes procedure between 1989 and 2011. Patient demographics, clinical variables and outcome data were collected. Data is presented as mean ± standard errors or median (interquartile ranges). Results: 26 patients (12, 46% boys) underwent Starnes procedure at 7 (5-9) days of life. All were intubated and on prostacyclin infusion, 24 (92%) were inotrope-dependent and 23 (88%) had no antegrade flow from the RV. Two patients had had prior intervention (one tricuspid annuloplasty and one shunt alone). Three patients underwent non-fenestrated RV exclusion, two (67%) of whom died. Of the remaining 23, 3 (13%) died during the same hospitalization. The 21 neonatal survivors have been followed for 7 (6-8) years. One patient died after Glenn. The remaining 20 have successfully undergone Fontan completion with an indexed pulmonary resistance of 1.8 (1.2-2.3) W/m2 and mean pulmonary pressure of 12 (9-18) mm Hg. At last follow-up, all patients have normal left ventricular function, and all but one patient are in NYHA Class I symptoms. Two patients have required pacemaker implantation, while the rest are in sinus rhythm. Survival at 1, 5 and 10 years are 81±4%, 77±3% and 77±3%, respectively. Conclusion: Long-term single ventricle outcomes amongst neonatal survivors of modified Starnes procedure are excellent. There is reliable remodeling of the excluded RV and excellent function of the left ventricle.

Severe and continuous arcs in transmission lines systems can be detrimental to the RF sources and the associated transmission lines. In order to prevent any damage to the whole system, arc detection and protective system shutdown are required for ITER ICH operations. In this case, it is desired to locate and replace the damaged transmission line sections caused by the arcs during routine maintenance; thus identifying the arc location during each occurrence will be needed to facilitate the maintenance work. There have been quite a few proposals for localizing the arcs positions in the past. However, there has been no major breakthrough in this research topic especially when the number of detectors is finite and limited. Because the ITER transmission lines are pressurized with dry air, each arc event will be accompanied with a shock wave propagating through the transmission lines. In this case, it is possible to determine the arc location by using two acoustic detectors in the transmission line under ideal conditions.

Winegrape vine pruning require repetitive gripping and awkward body postures. The purpose of this study is to examine the effects of cutting height and forearm posture on trunk and wrist posture, force production, and muscle activities during simulated vine pruning. Ten healthy subjects (3 female and 7 male) participated in the study. Subjects cut dowels simulating shoots with pruning shears at 5 cutting heights tailored to subject anthropometry at three forearm postures. Trunk and wrist kinematics, force exertion, and forearm EMG were monitored. The results showed significant change in force exertion; and trunk and wrist kinematics in stature and knee cutting heights. The information from this study could assist in ergonomic trellis design, injury prevention, and manual labor work guidelines.

Nanostructured membrane structures have been fabricated by a combination of anodic aluminum oxidation (AAO) and atomic layer deposition (ALD) for use as platforms for the synthesis of highly uniform heterogeneous catalysts. The ALD method makes it possible to control pore diameters on the Angstrom scale even when the overall pore diameter is 10’s to 100’s of nanometers. AAO membranes imbedded in an aluminum sealing ring have been tested for flow properties and found to follow Knudsen diffusion behavior. Vanadia-coated membranes have been tested for the catalytic oxidative dehydrogenation of cyclohexane and show improved selectivity at the same conversion compared to conventional powdered alumina supported vanadia catalysts.

The purpose of the present study is to investigate laminar fully developed flow in a horizontal rectangular channel with a cylinder solutal source adjacent to planar boundary. The boundaries in this experiment include four cases:(A) Cylinder is cathode and top plate is anode;(B) Cylinder is anode and top plate is cathode;(C) Cylinder is cathode and bottom plate is anode;(D) Cylinder is anode and bottom plate is cathode.The influences of the mass transfer rate and the boundary types between the sources have also been investigated. An experimental investigation of mixed convection mass transfer between a cylinder and a plate mass source with an electrochemical system is carried in a horizontal rectangular channel. The working fluid here is CuSO4 + H2SO4 + H2O. The shadowgraph technique is used to visualize the flow and to determine the nature and effect of solutal driven secondary flows in a horizontal channel. The ranges of the parameters in the work are Pr = 7, Ar = 1, Sc = 1700 ∼ 2400, Re = 50 ∼ 200 (Red= 12.5 ∼50), Grm = 9.45 × 105, d/H = 0.25, h/d=0, 3.

Autoimmune thyroiditis (AT) is characterized by a continuous inflammatory self-destructive process that eventually leads to chronic progressive dysfunction of the thyroid. In a previously established experimental AT model, C57bl/6 mice immunized with recombinant mouse thyroid peroxidase (TPO) (rmTPO) developed lymphocytic thyroiditis and anti-TPO antibody but not chronic hypothyroidism. To determine the immunodominant epitope(s) of TPO, T cell proliferation assays were performed in which rmTPO-primed lymph nodes cells were reacted with recombinant mTPO fragments or short overlapping synthetic TPO peptides. Within residue 405-849, peptide 540-559 gave the maximum proliferation response with a stimulation index more than 12. Mice immunized with peptide 540-559 developed antibody against rmTPO and native mouse TPO protein, lymphocytic thyroiditis, and hypothyroidism. In conclusion, this study demonstrated that TPO is the autoantigen for the development of lymphocyte thyroiditis and thyroid dysfunction, and peptide 540-559 is the immunodominant T cell epitope of TPO. Identification of T cell epitopes of TPO may enable the development of immunotherapy to prevent chronic hypothyroidism in AT.

The adsorption of CO and its reaction with oxygen were investigated using a combination of in situ Fourier transform infrared spectroscopy, step response measurements in a microreactor, (18)O isotopic labeling, and X-ray absorption near edge structure spectroscopy. An as-prepared sample in which Au is present as a surface oxyhydroxy complex does not adsorb CO. On an activated sample in which only metallic Au is detected, 0.18 +/- 0.03 mol CO/(mol Au) are adsorbed on Au at -60 degrees C, which shows an IR band at 2090 cm(-1). When oxygen is present in the gas phase, this species reacts with a turnover rate of 1.4 +/- 0.2 mol CO(mol Au min)(-1), which is close to the steady-state turnover rate. In contrast, there is a very small quantity of adsorbed oxygen on Au. A small IR peak at 1242 cm(-1) appears when an activated sample is exposed to CO. It reacts rapidly with oxygen and is shifted to 1236 cm(-1) if (18)O is used. It is assigned to the possible intermediate hydroxycarbonyl.

Conjugated linoleic acid (CLA) was covalently immobilized onto cellulose acetate (CA) membranes. The effects of CLA immobilization on the blood coagulation, platelet aggregation, and oxidative stress were evaluated using human blood. The resulting CLA grafting CA membranes were characterized with X-ray photoelectronic spectroscopy (XPS). The complete blood count (CBC) and coagulation time (CT) was evaluated in vitro for the hemocompatibility. Human serum albumin (HSA) and human plasma fibrinogen (HPF) was evaluated for the protein affinity. The production of reactive oxygen species (ROS) was measured by chemiluminescence (CL) method to evaluate the oxidative stress. The results showed that the CLA-immobilizing CA membrane could keep the CBC values more stable than unmodified CA membrane. The CLA-immobilized CA membranes also showed longer CT and less adsorption of plasma proteins. CLA-immobilized CA membrane could keep the CL counts of hydrogen peroxide and superoxide values more stable than unmodified CA membrane. These results suggest that a CLA-immobilized CA membrane could offer protection for patients against oxidative stress and would be helpful for reducing the dosage of anticoagulant during hemodialysis.

MIT and PPPL have joined together to fabricate a high-power lower hybrid current drive (LHCD) system for supporting steady-state AT regime research on Alcator C-Mod. The goal of the first step of this project is to provide 1.5 MW of 4.6 GHz rf power to the plasma with a compact launcher which has excellent spectral selectivity and fits into a single C-Mod port. Some of the important design, construction, calibration and testing considerations for the launcher leading up to its installation on C-Mod are presented here.

The catalytic performance of Au/Al 2 O 3 catalyst is highly sensitive to preparation procedure. EXAFS and TEM characterization of key steps in the preparation in conjunction with activity measurements result in deeper insights into precautions needed and the complex manner residual chloride impacts catalytic activity. Chloride affects the morphological (Au particle size), chemical (reducibility) as well as the catalytic (poisoning) properties of Au. Alternate preparation procedures to the conventional calcination of a catalyst prepared with deposition–precipitation at neutral pH were explored to increase Au loadings. It was found that low temperature H 2 reduction of a catalyst prepared at low pH but washed with NaOH is an effective preparation method.

This article summarizes a unique approach in which all-ceramic interconnects are used in place of metal interconnects in solid-oxide fuel cell (SOFC) stacks. The approach combines advanced SOFC materials with the manufacturing technology and infrastructure established for multilayer ceramic (MLC) packaging for the microelectronics industry. The MLC interconnect is fabricated using multiple layers of yttria-stabilized zirconia (YSZ) tape, with each layer containing conductive vias to provide for electrical current flow through the interconnect. The all-ceramic interconnect design facilitates uniform distribution of air and fuel gas to the respective electrodes of adjacent cells. The multilayer interconnects are fabricated using traditional MLC manufacturing processes. A detailed description of the processes for fabricating the all-ceramic interconnect is presented.To aid in moving from prototype fabrication to commercialization of these fuel cell systems, a detailed cost model has been used as a roadmap for commercial stack development. Cost model projections are presented for three different interconnect footprint sizes. These projections show an SOFC stack cost of less than $150 per kilowatt for the optimized SOFC stack design produced at high volume.

Atomic layer deposition (ALD) on anodic aluminium oxide (AAO) is shown to be a facile, flexible route to the synthesis of catalytic membranes with precise control of pore wall composition and diameters. The oxidative dehydrogenation of cyclohexane was shown to depend strongly on pore diameter and to be more specific than similarly active alumina powder catalysts.

Anodic aluminum oxide (AAO) membranes were characterized by UV Raman and FT-IR spectroscopies before and after coating the entire surface (including the interior pore walls) of the AAO membranes by atomic layer deposition (ALD). UV Raman reveals the presence of aluminum oxalate in bulk AAO, both before and after ALD coating with Al2O3, because of acid anion incorporation during the anodization process used to produce AAO membranes. The aluminum oxalate in AAO exhibits remarkable thermal stability, not totally decomposing in air until exposed to a temperature900 degrees C. ALD was used to cover the surface of AAO with either Al2O3 or TiO2. Uncoated AAO have FT-IR spectra with two separate types of OH stretches that can be assigned to isolated OH groups and hydrogen-bonded surface OH groups, respectively. In contrast, AAO surfaces coated by ALD with Al2O3 display a single, broad band of hydrogen-bonded OH groups. AAO substrates coated with TiO2 show a more complicated behavior. UV Raman results show that very thin TiO2 coatings (1 nm) are not stable upon annealing to 500 degrees C. In contrast, thicker coatings can totally cover the contaminated alumina surface and are stable at temperatures in excess of 500 degrees C.

Reduced height waveguide arrays are commonly used in fusion plasma radio frequency heating in the lower hybrid frequency range. In order to distinguish the incident wave and the reflected wave, power detection with high directivity in each reduced height waveguide is required. Due to the confined space in a stack of reduced height waveguides, power detection with high directivity in the reduced height waveguide is extremely difficult, especially from the wide side of the waveguide by using a conventional E probe. A new compact probe, which employs current loops, to monitor the incident and reflected wave from the narrow side of the reduced height waveguide has been developed. According to the test data, greater than 35 dB of directivity was measured with this compact probe at 4.6 GHz.

The purpose of present study is to investigate laminar fully developed flow in a horizontal rectangular channel with the tandem cylinder sources under different Re and source positions. The boundaries in this experiment include four cases: a. the former cylinder is cathode and the latter cylinder is anode; b. the former cylinder is anode and the latter is cathode; c. the upper plate is cathode and two cylinders are anode; and d. the two cylinders are cathode and upper plate is anode. The influence of the mass transfer rate and the boundary types between the sources have also been investigated. An experimental study of mixed convection with CuSO4 plus; H2SO4 + H2O solution in a horizontal channel was performed. The shadowgraph technique was used to visualize the flow and to determine the nature and effect of solutal driven secondary flows in a horizontal channel with the tandem cylinder sources inside. The ranges of the parameters studied in the present work are Pr = 5–7, Ar = 1, Sc = 1700–2400, R...

Objectives Conventional prenatal screening for congenital heart disease (CHD) involves a time-consuming and highly operator-dependent acquisition of the four-chamber view and outflow tracts. By acquiring the entire fetal heart instantaneously as a single volume, real-time three-dimensional echocardiography (RT3DE) may facilitate fetal cardiac screening. Methods Four reviewers, each experienced with fetal cardiac imaging, blindly and independently evaluated a single cardiac volume from each of 18 fetuses (11 normal, seven with CHD). Two-dimensional echocardiography served as the gold standard. Three-dimensional evaluation of each fetus included a series of volume acquisitions lasting 2–6 s each. A ‘sweep volume’ technique was developed to fit larger hearts into a single non-gated volume. Results RT3DE had a high sensitivity for detecting CHD (93%), with only a single case being missed by two observers. Specificity for CHD was low (45%), with a high rate of ‘cannot determine’ responses and false positive artifacts. Conclusions These preliminary results suggest that RT3DE has the potential to function as a screening tool for fetal heart disease. However, artifacts must be recognized and minimized, resolution must improve, and substantial training will be necessary prior to widespread clinical use. Copyright © 2005 ISUOG. Published by John Wiley & Sons, Ltd.

Navigator coronary magnetic resonance imaging (MRI) was evaluated in assessing coronary artery origins in a pediatric and adolescent population. Sixty-five consecutive infants, children, or adolescents (age range 11 days to 21 years) were referred for MRI evaluations to assess coronary artery origins. Coronary artery origins were unambiguously delineated in 62 of 65 patients. In 3 patients, irregular arrhythmias precluded cardiac gating of the magnetic resonance acquisition. Two patients had anomalous coronary artery origins detected. Twenty-six patients required sedation for the studies. Free-breathing 3-dimensional MRI with real-time navigator correction is a robust method for delineating the coronary artery origins in pediatric and adolescent patients.

Autoimmune thyroid disease (AITD) may occur in patients after hematopoietic stem cell transplantation (HSCT). In all, 10 cases of AITD (seven allogeneic and three autologous HSCT) were diagnosed among 721 HSCT recipients, including two patients with sequential hyper- and hypothyroidism. The 5-year actuarial rates for AITD after allogeneic and autologous HSCT were 2.9 and 4%, respectively. Significant risk factors included HSCT for chronic myeloid leukemia, the HLA B46 and DR9 loci and the A2B46DR9 haplotype, while female donors showed trend to significance. On multivariate analysis, only female donors and HLA DR9 remained significant. For autologous HSCT, the associations with HLA B46 and DR9 were also significant. Only three donors had a family history of AITD. A review of other reported cases confirmed the predominance of female donors, although the other associations including graft-versus-host disease, familial AITD and other autoimmune phenomena might be related to reporting bias. Since the actuarial incidence of AITD from female donors with predisposing HLA alleles may be over 30%, susceptible recipients should be carefully monitored. Owing to the small number of reported cases and different HLA associations with AITD in different populations, our observations await confirmatory data from other registries.

CO impedes the low temperature (

Background Patients undergoing operative repair of aortic obstruction are at a lifelong risk of recurrent obstruction, and there is controversy regarding the optimal surgical technique. We have used an alternative strategy for recurrent aortic obstruction, typically involving anatomic reconstruction by means of a median sternotomy, and describe our techniques and results. Methods Twenty-one patients presented with recurrent aortic arch obstruction. Mean age and weight were 7.8 ± 5.4 years (range, 0.21 to 15.2 years) and 30.6 ± 21.8 kg (range, 3.6 to 90 kg), respectively. Recurrence involved the aortic arch to some degree in each case, as the mean preoperative transverse aortic arch z score was −2.9 ± 1.6 (range, −7.0 to 0.1). Thoracotomy was possible in 2 patients, using re-resection with end-to-end anastomosis (n = 1) and patch aortoplasty (n = 1). The remaining 19 patients required median sternotomy, cardiopulmonary bypass, and deep hypothermic circulatory arrest for complete relief of obstruction by aortic arch advancement (n = 10), patch aortoplasty (n = 8), or interposition grafting (n = 1). Results There was 1 hospital death. Invasive blood pressure monitoring revealed no residual arm-to-leg gradient in 19 patients and a 20-mm Hg gradient in 2 patients. There have been no late deaths. No patients have undergone subsequent aortic intervention, and all are asymptomatic up to 85 months postoperatively. Two patients are currently followed with a 10-mm Hg arm-to-leg blood pressure gradient. Conclusions Anatomic reconstruction for recurrent aortic obstruction can be safely accomplished in the majority of patients. We favor median sternotomy because of the ability of establishing cardiopulmonary bypass, the facility of anatomic reconstruction techniques, and the ability to repair concomitant cardiovascular lesions.

An experimental study of thermosolutal convection in an inclined rectangular enclosure with a partition is presented in this article. Aspect ratio, partition ratio, and inclination angle were kept constant at Ar =0.5, Ap = 0.25 and φ = 30°, respectively. The convective flow is generated by both inclined temperature and concentration gradients under limiting current condition. Both the thermal and solutal buoyancies, which either cooperated or opposed one another, were induced from the copper plates. The temperature gradient was maintained and controlled using two separate constant temperature baths that circulated heated or cooled water through a heat exchanger. We used copper sulphate-sulfuric acid solution as both the working fluid and the electrolyte. An electrochemical method based on a diffusion-controlled electrode reaction was employed to create the concentration gradient. We used the shadowgraph recording technique to visualize and analyze the flow field phenomenon. Thermal Grashof numbers ranging from 8.16 × 105 to 16.32 × 105 and a solutal Grashof number Grm = 4.36 × 106 were investigated. It is demonstrated that the mass transfer rate increases with the increasing thermal Grashof numbers within our experimental ranges. Multilayer structures are found in the cooperating case or the opposing case.

Gold catalysts supported on γ-Al2O3 (Au/γ-Al2O3) were prepared by deposition-precipitation of aqueous HAuCl4 and, alternatively, by deposition of Au(CH3)2(acac) from pentane solution. The samples were characterized by in situ XANES and temperature-programmed reduction and by their performance as CO oxidation catalysts at room temperature. The Au was found to be present as Au(III) in both as-prepared catalysts, and the Au(III) was stable upon exposure to reducing gases at room temperature. Reduction of Au(III) occurred at elevated temperatures, and the rate and extent of reduction were found to depend strongly on the reducing conditions. Water vapor facilitated reduction, but only after the sample had been reduced to some extent by CO or H2. Exposure of an as-prepared catalyst to a catalytically reacting mixture of CO + O2 at 100 °C was effective in activating it, though to a lesser extent. The data indicate that zerovalent Au is necessary for catalytic activity, but there is no correlation between the act...

The catalytic conversion of benzoic acid to phenol in the presence of water and oxygen was studied in the vapor phase over nickel oxide on various supports. NiO/SiO2 was the most selective, and the selectivity reached over 50% using iron oxide and sodium oxide modifiers. Ni–Fe oxide prepared by coprecipitation deactivated with time-on-stream, but that prepared using a cellulose templating method was more stable. Benzene was often a significant by-product. Some coupling products were formed, including xanthone, fluorenone, and biphenyl. From deuterium isotope labeling experiments, the hydroxyl group was found to be formed at the carbon next to the one with the carboxylic acid group.

The nitrogen formation efficiencies, defined as the number of nitrogen molecules formed for every reductant molecule consumed were determined for acetaldehyde and propionaldehyde in the reduction of NO2 under lean conditions over anatase TiO2. The efficiency increased with increasing NO2/reductant in the feed, reaching 0.61 ± 0.05 for NO2/acetaldehyde between 1.5 and 3.0 and 0.85 ± 0.08 for NO2/propionaldehyde between 3.8 and 5.7. Simultaneously, the CO/CO2 ratio as well as the small concentration of N2O in the product stream increased. The results suggested that at higher NO2/reductant ratios, the reaction between the reductant and adsorbed NO2 accounted for a large majority of the reaction. The results were consistent with the IR results, which showed that surface nitro groups reacted readily with acetaldehyde. The implications of these results on the NO2 reduction mechanism were discussed.

Background It has previously been suggested that significant dilatation of the coronary sinus can contribute to left ventricular inflow obstruction and is amenable to surgical correction. The purpose of this study was to review our experience with this rare condition. Methods Since 1995, 6 patients have undergone coronary sinus reduction for concerns of obstruction with other concomitant intracardiac repairs. Preoperative echocardiography identified a significantly dilated left superior vena cava to the coronary sinus in 5 patients (83%) and an abnormal mitral valve in 4 patients (67%); these resulted in abnormal Doppler inflow patterns. Preoperative cardiac catheterization was performed in 5 patients and revealed increased atrial "a" waves, with a gradient to the left ventricular end-diastolic pressure in each case. At the time of surgery, coronary sinus angioplasty was performed in all patients. Results There were no deaths, and there was no major morbidity. Follow-up imaging revealed no significant left ventricular inflow obstruction in any patient. Conclusions We conclude that dilatation of the coronary sinus can become hemodynamically significant and that coronary sinus angioplasty is a safe and effective technique.

The present state of knowledge of NO x reduction under lean conditions over metal oxides is summarized in this review, with an emphasis on the reaction mechanism. Although a number of nitrogen-containing intermediates have been observed and implied, including organic nitro, nitrite, cyanide, isocyanate, and ammonia, there is yet definitive observation that confirms the relevance of these to the principal reaction pathway. Individual component in a mixed oxide catalyst can participate at different stages of the NO x reduction reaction. The nitrogen production efficiences for different oxide based catalysts are summarized, and their relationship to the nature of the catalyst is discussed.

An experimental investigation of heat transfer carried out for a semiannular enclosure. Inner and outer walls of the enclosure were kept at different but constant temperatures. The semiannular enclosure was filled with a CuSO4 - H2SO4 - H2O solution. An electrochemical method has been used for the mass transfer. The purpose of this study is to investigate flows resulting from buoyancy due to a combination of both temperature and concentration gradients in the enclosure. The flow structure in the enclosure was visualized by the shadowgraph technique. Flow visualization photograph showed interesting multi-cell flow structures in the enclosure for the cooperating and opposing thermal and solutal buoyancy. An optical technique is based on the idea that the intensity of the light beam absorbed by the copper sulphate solution is proportional to the solution concentration when the light beam passes through the solution. For each flow regime the mass transfer coefficient across the enclosure was also measured. The ranges of the dimensionless parameters studied in the experimental were Ar = 0.23, k = 2.5, Sc = 1700∼2300, Pr = 6.5 ∼ 7.3, Grt = 104 ∼ 106, N = −15.44 ∼ 6.16, θ = 45°∼90°.

Autoimmune thyroid disease (AITD) is a common autoimmune disease. Thyroid peroxidase (TPO) is a well characterized autoantigen in AITD. Autoantibodies and autoreactive T lymphocytes to TPO are believed to play a major role in the pathogenesis of lymphocytic thyroiditis. To understand the pathogenic mechanisms of AITD and the role of TPO, we have established a mouse model of lymphocytic thyroiditis by immunizing C57Bl/6 (H-2b), CBA (H-2k), and C57Bl/6 × CBA F1 mice with recombinant murine TPO (rmTPO) ectodomain comprising amino acid residue 1–837 produced in Escherichia coli. Mice were immunized with 30 μg purified ectodomain in complete Freund’s adjuvant. Antibodies against rmTPO were detected in the serum of all mice from day 21 onward. Draining lymph node cells from rmTPO-immunized animals showed dose-dependent proliferation to TPO stimulation. Mice killed at d 50 and 90 revealed variable degrees of thyroiditis with infiltration of mononuclear cells and destruction of thyroid follicles. C57Bl/6 and the F1 mice, in comparison with CBA mice, showed a greater degree of thyroiditis. There was a lack of correction between the intensity of thyroiditis and the anti-TPO response. Immunotyping of the thyroid cellular infiltrates showed predominantly CD4+ T cells and B220+ B cells but scanty CD8+ T cells. None of the control mice injected with the purified fusion partner developed anti-TPO antibodies and thyroiditis. In conclusion, a genuine autoimmune mouse model of lymphocytic thyroiditis was established using autologous mouse TPO. This new model induced with autologous TPO will lead to a better understanding of the mechanisms in destructive thyroiditis and will assist in the development of new strategies for modulating the pathogenic immune response.

Laser flash photolysis is used to examine reaction rates of four arylnitrenium ions: N-methyl-N-(4-chlorophenyl)-, -(4-biphenylyl)-, -(4-methylphenyl)-, and -(4-methoxyphenyl)nitrenium ion. These intermediates are generated from photolysis of appropriately substituted N-aminopyridinium ions. Kinetic analysis of trapping rates shows that the nitrenium ions react with weak nucleophiles in the order 4-Cl approximately 4-Me4-Ph4-OMe. Generally, amines react with the arylnitrenium ions at or near the diffusion-limited rate. Only in cases where the least reactive nitrenium ion (4-OMe) reacts with sterically hindered amines is any deviation from this generalization observed. The addition of a 2-acetyl substituent to these structures produces an interesting effect. In the case of the 4-Cl and 4-Ph analogs, the electron-withdrawing acetyl group decreases the rate of nucleophilic addition, yet with the 4-OMe and 4-Me compounds, the acetyl group increases the rate of addition. These results are discussed in terms of competing electronic and steric effects.

The catalytic activities of alumina prepared from an Al alkoxide-amine adduct monomer for the reaction of cyclopentene oxide with piperidine was determined after various pretreatments, including calcination and exposure to moisture. They were compared with the activity of alumina prepared by the conventional hydrolysis method. It was found that the as-prepared sample from the alkoxide-amine monomer preparation was five times more active than a conventional preparation, suggesting that it has a higher density of surface Lewis acid sites. However, its activity was much more severely suppressed by exposure to moisture.

We report the success of transcatheter coil embolization of congenital coronary artery fistulas in infants and young children, primarily using a retrograde coaxial delivery system. Transcatheter coil embolization of coronary artery fistulas has been used successfully in the adult population with limited reports in the pediatric population, especially in infants. Ten patients underwent transcatheter coil embolization of congenital coronary artery fistulas between January 1993 and August 1999. The median age was 4.5 years (ranging from 5 weeks to 9.8 years). Coils were delivered exclusively using a retrograde arterial approach in 8 of 10 patients. A coaxial system was used in 8 patients. Angiography immediately after placement of coils revealed no residual shunt in any patient. Recent follow-up evaluation is available for 9 patients (median duration of follow-up, 7.9 months). Echocardiographic and clinical evaluations show complete occlusion in 8 of 9 patients. All patients are asymptomatic with normalization of chamber dimensions and coronary artery caliber. Transcatheter coil embolization of congenital coronary artery fistulas can be performed safely and successfully in infants and young children. The use of a retrograde approach and coaxial system is safe and effective and may provide better accuracy, stability and precision for placement of coils.