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51.
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G Manenti L De Gregorio S Pilotti FS Falvella M Incarbone F Ravagnani MA Pierotti TA Dragani 《Canadian Metallurgical Quarterly》1997,18(10):1917-1920
The mapping near Kras2 of pulmonary adenoma susceptibility 1 (Pas1), a major locus affecting inherited predisposition to lung cancer in mice prompted us to test the homologous human region (12p12) for association with lung adenocarcinoma, by a population-based study. We genotyped 213 lung adenocarcinoma patients and 219 healthy blood donor subjects for five polymorphic markers mapping in the putative region of interest. Three marker polymorphisms, located in a region spanning approximately 700 kb, were significantly associated with lung adenocarcinoma risk. Furthermore, polymorphisms in KRAS2 and PTHLH loci were also associated with tumor prognosis. These results suggest the existence of a human Pas1 homologous locus on chromosome 12p12. 相似文献
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Theories and observations on the causes of disintegration of fireclay refractories in blast furnaces are given and a process is developed for improving high iron clays for this use. The disintegration of refractories in blast furnace linings is initiated by alteration in the iron spots. Ferric oxide is reduced to ferrous oxide at 500°C and hastens the cracking of 2CO to CO2+C1 the carbon being retained by the lining. When Fe2O2 is converted to Fe3O4 the brick will not disintegrate. 相似文献
55.
Examined the effects of a genetic probe that can provide individuals at risk for Huntington's disease (HD) with diagnostic information regarding this progressive genetic disorder before symptoms are exhibited. 113 at-risk HD individuals were informed about the genetic probe, and their level of anxiety was assessed. A group conference format was an effective means of providing information regarding the HD probe to a large number of at-risk families. Findings from the measure of anxiety demonstrate that the at-risk HD population is no different from a normative population or from an at-risk HD population unfamiliar with the new technology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
56.
Feng M. Brilliant N. A. Cundiff S. T. Mirin R. P. Silverman K. L. 《Photonics Technology Letters, IEEE》2007,19(11):804-806
We report a two-section mode-locked quantum-dot laser with an emission wavelength that is bistable with respect to applied bias on the saturable absorber region. The two stable lasing wavelengths for this device are about 1173 and 1166 nm with a power contrast ratio of over 30 dB. The largest switchable wavelength range is 7.7 nm. The optical power and pulsewidth (6.5ps) are almost identical in the two lasing modes under optimized conditions. The operation of this laser can be explained by the interplay of the spectral-hole burning and the quantum-confined Stark effect 相似文献
57.
Dechlorination of polychlorinated biphenyls in industrial transformer oil by radiolytic and photolytic methods 总被引:3,自引:0,他引:3
Jones CG Silverman J Al-Sheikhly M Neta P Poster DL 《Environmental science & technology》2003,37(24):5773-5777
Used electrical transformer oils containing low or high concentrations of polychlorinated biphenyls (PCBs) were treated using electron, gamma, and ultraviolet radiation, and the conditions for complete dechlorination were developed. Dechlorination was determined by analysis of the inorganic chloride formed and the concentrations of remaining PCBs. Transformer oil containing approximately 95 microg g(-1) PCB (approximately 3.5 mmol L(-1) Cl) is completely dechlorinated by irradiation with 600 kGy after the addition of 10% triethylamine (TEA). Transformer oil containing >800,000 microg g(-1) PCB (17.7 mol L(-1) Cl) requires an additional solvent to prevent solidification. When this oil is diluted with 2-propanol (2-PrOH) and TEA (v/v/v, 1/79/20), complete dechlorination is achieved with a dose of 2500 kGy. Ultraviolet photolysis of the same oil/2-PrOH/TEA solutions led to 90% dechlorination after exposure for 120 h in our experimental setup. Such yields were obtained by radiolysis with a dose of 2000 kGy (300 h in our Gammacell). Replacing TEA with KOH in 2-PrOH solutions greatly increases the yield of dechlorination in both the radiolytic and the photolytic experiments, demonstrating that a chain reaction plays a role in both of these treatment methods and suggesting that both methods deserve further consideration for large-scale application. 相似文献
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59.
Reinherz Helen Z.; Giaconia Rose M.; Hauf Amy M. Carmola; Wasserman Michelle S.; Silverman Amy B. 《Canadian Metallurgical Quarterly》1999,108(3):500
An ongoing longitudinal community study (N?=?375) examined childhood risks and later adult impairments associated with 1-year Diagnostic and Statistical Manual of Mental Disorders (3rd ed., rev.; American Psychiatric Association, 1987) diagnoses of major depression during the transition to adulthood. Risks from birth to age 9 were reported by mothers, participants, and teachers. Teacher-reported hostility at age 6 predicted later depression. At age 9, self-perceptions of anxiety/depression, unpopularity, familial rejection, and abuse were potent risks. For men, neonatal and childhood health problems predicted later depression. For women, risks included family constellation, parental death, and poor academic achievement at age 9. Men and women who were depressed at age 18, age 21, or both demonstrated extensive psychosocial impairments in early adulthood, including poor overall functioning, interpersonal and behavioral problems, low self-esteem, and suicidality. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
60.
F. Pellemoine W. MittigM. Avilov D. IppelJ. Lenz J. OlivaI. Silverman D. YouchisonT. Xu 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,655(1):3-9
One of the major challenges of the FRIB project (Facility for Rare Isotope Beams) at Michigan State University is the design and integration of the production target to produce rare isotope beams via fragmentation reaction. In the most extreme case, a 400 kW uranium beam of 200 MeV/u will be focused in a 1 mm diameter spot, leading to a power density of 60 MW/cm3 for a C target. Up to 200 kW may be dissipated in the target.A rotating solid carbon disk concept has been selected as the target design approach for all primary beams up to uranium to provide high-power operation. A high rotational speed is necessary to compensate for the high power density. A multi-slice approach allows the evacuation of the large amount of heat deposited by the increase of the radiating area. In the present design study, the multi-slice target device has a diameter of about 30 cm and rotates at about 5000 RPM (revolutions per minute). The first step of the R&D strategy consists in the development and test of a 20 kW single-slice target prototype. This single disk device is designed to accept the same fraction of power as each disk of the final multi-slice target. Critical information on thermal-mechanical properties can be obtained thus at a lower power level than the one of the full device. Different carbon materials were tested. An electron beam of ∼20 keV was used for the thermal tests. Simulations were performed using the ANSYS code for the thermo-mechanical behaviour of the target, the resulting deformation and the stress profiles of heated graphite disks. Results of the simulations were compared with experimental data. 相似文献