Adaptive response in embryogenesis: I. Dose and timing of radiation for reduction of prenatal death and congenital malformation during the late period of organogenesis

BACKGROUND: Coexistent primary biliary cirrhosis (PBC) and coeliac disease has been recorded but the association has not been systematically studied. AIMS: To determine relative prevalences of PBC and coeliac disease in a defined population over a 12 year period. PATIENTS AND METHODS: All patients with PBC or coeliac disease in a stable population of 250,000 in South Wales were identified from a clinical register and laboratory records. RESULTS: Sixty seven patients with PBC and 143 patients with coeliac disease have been diagnosed and followed over a median of 86 (4-135) months; point prevalences in 1996 were 20 per 100,000 for PBC and 54 per 100,000 for coeliac disease. PBC in patients with coeliac disease was sought by investigating abnormal liver function tests. Ten (7%) had persistent abnormalities and three had PBC. Coeliac disease in patients with PBC was sought by investigating malabsorption, haematinic deficiency, positive antigliadin antibody, or coeliac disease family history. Eleven patients underwent duodenal biopsy revealing one further coeliac disease case. Four patients (three women have both conditions giving a point prevalence for patients with both conditions of 1.6 per 100,000 (95% confidence limits 0.44 to 4.1 per 100,000). Prevalence of PBC in patients with coeliac disease was 3% and of coeliac disease in patients with PBC was 6%. CONCLUSION: A 12 year study of a stable 250,000 population revealed a relative prevalence of PBC in 3% of 143 patients with coeliac disease and of coeliac disease in 6% of 67 patients with PBC. PBC and coeliac disease are therefore associated. Screening for PBC in patients with coeliac disease using antimitochondrial antibody testing and screening for coeliac disease in patients with PBC with antigliadin antibody testing or duodenal biopsy are recommended.     

Heat transfer of combined forced and natural convection from horizontal cylinder to air

Experimental investigations have been carried out for combined convective flows of air induced around uniformly heated, horizontal cylinders. Three cases of aiding, opposing, and cross flows were examined. The experiments covered the ranges of the Reynolds and modified Rayleigh numbers of Re_d=50 to 900 and Ra_d^*=5×10⁴ to 3×10⁶. The flow fields around the cylinders were visualized with smoke. The results showed that separation points gradually shift from those of the forced convection to the top edge of the cylinder with increasing wall heat fluxes. The local heat transfer coefficients of the cylinders were also measured. Although the local coefficients show complex variations with the forced flow velocities and the wall heat fluxes, the overall coefficients become higher than those estimated from pure forced and natural convections throughout the cases of aiding, opposing, and cross flows. Moreover, it was confirmed that the overall Nusselt numbers as well as the separation points can be predicted with the non‐dimensional parameter (Gr_d^*/Nu_dRe_d²). © 2007 Wiley Periodicals, Inc. Heat Trans Asian Res, 36(8): 474–488, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20180     

Seismic tests of a pile-supported structure in liquefiable sand using large-scale blast excitation

Extensive, large-amplitude vibration tests of a pile-supported structure in a liquefiable sand deposit have been performed at a large-scale mining site. Ground motions from large-scale blasting operations were used as excitation forces for vibration tests. A simple pile-supported structure was constructed in an excavated 3 m-deep pit. The test pit was backfilled with 100% water-saturated clean uniform sand. Accelerations were measured on the pile-supported structure, in the sand in the test pit, and in the adjacent free field. Excess pore water pressures in the test pit and strains of one pile were also measured.Vibration tests were performed with six different levels of input motions. The maximum horizontal acceleration recorded at the adjacent ground surface varied from 20 Gals to 1353 Gals. These alternations of acceleration provided different degrees of liquefaction in the test pit. Sand boiling phenomena were observed in the test pit with larger input motions. This paper outlines vibration tests and investigates the test results.     

Near-IR sensitization of nanocrystalline TiO2 with a new ruthenium complex having a 2,6-bis(4-carboxyquinolin-2-yl)pyridine ligand

A new ruthenium(II)–polypyridine complex (1) having a 2,6-bis(4-carboxyquinolin-2-yl)pyridine ligand was synthesized as a sensitizer for dye-sensitized solar cells (DSCs). This complex exhibited remarkable light-harvesting properties in the near-IR region. DSCs sensitized with 1 showed a 35% incident photon-to-current conversion efficiency (IPCE) at 900 nm.     

Gibbs Energy Change of Carbothermal Nitridation Reaction of Al2O3 to Form AlN and Reassessment of Thermochemical Properties of AlN

The experimental method for the high-temperature reaction equilibria in the AlN-Al₂O₃ system has been established. The equilibrium N₂-CO gas compositions coexisting with AlN- Al₂O₃-graphite have been successfully measured by quadrupole mass spectrometry and gas chromatography. From the obtained results, the standard Gibbs energy change of the forming reaction of AlN by carbothermal nitridation is determined at temperatures ranging from 1723 to 1899 K:
From the obtained result, the standard Gibbs energy of formation of AlN and the third-law enthalpy of formation of AlN at 298.15 K are derived as
The disagreement between the present results and values in the NIST–JANAF thermodynamic table is discussed.     

Effects of Spraying Ozonated Water on the Severity of Powdery Mildew Infection on Cucumber Leaves

Effects of spraying ozonated water on the severity of powdery mildew infection, visible disorder/injury occurrence, and net photosynthesis in cucumbers were investigated. The severity in the ozonated water treatment was contained to almost the same level throughout the 14-day period of the experiment, while the severity steadily increased in the non-treated control and distilled water treatment. Neither visible disorder/injury on the leaves nor a large difference in net photosynthesis between before and after spraying the ozonated water was observed. The results indicate that ozonated water can be at least a partial alternative to agricultural chemical fungicides for powdery mildew on cucumber leaves.     

An automatic Euler solver using the unstructured upwind method

A fully-automatic grid generator and an unstructured upwind method for the Euler equations are developed in order to achieve automation in flow computations. The unstructured grid is generated using two techniques: a geometry-adaptive refinement; and a solution-adaptive refinement. The former introduces information about the flowfield geometry into the grid, and the latter introduces the fluid physics. A combination of these two techniques enables the generation of a grid in a fully-automatic manner. Flowfields are solved by an unstructured upwind solver, which is an extension of the flux-vector splitting method of Van Leer for use on arbitrary-shaped unstructured meshes. This robust flow solver with the automatic grid generator can be a useful CFD tool for routine engineering work. The method is applied to external and internal flow problems to demonstrate its capability.     

Neurogenous tumors in head and neck region]

Detoxification of cyclophosphamide is effected, in part, by hepatic class 1 aldehyde dehydrogenase (ALDH-1)-catalyzed oxidation of aldophosphamide, a pivotal aldehyde intermediate, to the nontoxic metabolite, carboxyphosphamide. This enzyme is found in erythrocytes as well. Detoxification of aldophosphamide may also be effected by enzymes, viz. certain aldo-keto reductases, that catalyze the reduction of aldophosphamide to alcophosphamide. Such enzymes are also found in erythrocytes. Not known at the onset of this investigation was whether the contribution of erythrocyte ALDH-1 and/or aldo-keto reductases to the overall systemic detoxification of circulating aldophosphamide is significant. Thus, NAD-linked oxidation and NADPH-linked reduction of aldophosphamide catalyzed by relevant erythrocyte enzymes were quantified. ALDH-1-catalyzed oxidation of aldophosphamide (160 microM) to carboxyphosphamide occurred at a mean (+/- SD) rate of 5.0 +/- 1.4 atmol/min/rbc (red blood cell). Aldo-keto reductase-catalyzed reduction of aldophosphamide (160 microM) to alcophosphamide occurred at a much slower rate, viz. 0.3 +/- 0.2 atmol/min/rbc. Thus, at a pharmacologically relevant concentration of aldophosphamide, viz. 1 microM, estimated aggregate erythrocyte ALDH-1-catalyzed aldophosphamide oxidation, viz. 2.0 micromol/min, was only about 3% of estimated aggregate hepatic enzyme-catalyzed aldophosphamide oxidation, viz. 72 micromol/min; however, this rate is greater than the estimated flow-limited rate of aldophosphamide delivery to the liver by the blood, viz. 1.5 micromol/min. These observations/considerations suggest an important in vivo role for erythrocyte ALDH-1 in systemic aldophosphamide detoxification. Erythrocyte ALDH-1-effected oxidation of other aldehydes to their corresponding acids, e.g. retinaldehyde to retinoic acid, may also be of pharmacological and/or physiological significance since a wide variety of aldehydes are known to be substrates for ALDH-1.     

添加合金元素对奥氏体不锈钢等离子渗氮和渗碳的影响

奥氏体不锈钢众所周知有良好的耐蚀性,但是在工业上没有用于承受摩擦的工件上,因为它的硬度低,摩擦磨损性能差。奥氏体不锈钢经低温等离子体渗氮或渗碳能生成一层特殊的氮化物或碳化物层,称为S相,它具有高的硬度和优良的耐蚀性。这项研究中各种奥氏体不锈钢都经低温等离子体渗氮或渗碳,用各种分析技术研究了添加合金元素对S相特性的影响,用了光学显微镜和电子显微镜观察,做了X射线衍射分析,在5%H2SO4溶液中测量阳极极化,用球对平面摩擦装置做摩擦磨损测试。氮化物或碳化物层厚度随处理温度增加而加厚,AISI316钢上生成的渗层厚度是所有的基体钢材中最厚的。超过临界温度,由于氮化铬工碳化铬沉淀使耐蚀性降低。临界温度由渗氮的基材决定。另一方面,在渗碳层中临界温度不随基材变化。大部分样品上S相层的耐蚀性比没有处理的不锈钢的低。但是,AISI316和JIS-SUS304J3钢在400℃渗碳后都有和未处理钢一样优良的耐蚀性。每种不锈钢经渗氮或渗碳后耐磨性都有明显的改进。