Cyclic thermal exposure tests of infrared heating to 800 ℃ in 120 s followed by compressed air cooling to 150 ℃ in 60 s were performed for the laser deposited Ti60A （Ti5.54Al3.38Sn3.34Zr0.37Mo0.46Si） alloy. The ef...Cyclic thermal exposure tests of infrared heating to 800 ℃ in 120 s followed by compressed air cooling to 150 ℃ in 60 s were performed for the laser deposited Ti60A （Ti5.54Al3.38Sn3.34Zr0.37Mo0.46Si） alloy. The effects of thermal exposure cycles on length ofβphase, area fraction ofαphase and microhardness of alloy were examined by OM, SEM and EDS. The results indicate that thermal exposure cycles have significant effects on length ofβphase, area fraction ofαphase and microhardness of the alloy. The original fine basket-weaveβand 78.5%αtransform to transient wedge-likeβ, finally leaving granularβand 97.6%coarsenedαwith the increased thermal exposure cycles. The formation mechanism of coarsenedαand broken-upβmicrostructure is discussed. The alloy after 750 thermal exposure cycles has the maximum microhardness, 33.3%higher than that of the as-deposited alloy.展开更多
Background： Since it has been shown that spending 18 h under dim light conditions can result in reduced handgrip endurance, it was questioned whether or not a shorter exposure to dim light （i.e., 1 h） would have si...Background： Since it has been shown that spending 18 h under dim light conditions can result in reduced handgrip endurance, it was questioned whether or not a shorter exposure to dim light （i.e., 1 h） would have similar influence upon muscular endurance. Therefore this study compared the number of weighted knee extension lifts that could be done after spending 1 h in either dim or bright light. Methods： Participants （5 women, 11 men, college students 19--26 years） performed knee extension lifts to exhaustion with a load approximating 40% of their body weight. The lifts to exhaustion were measured immediately following 1 h of exposure to each of the following three con- ditions： dark （DL）, room light （RL）, and room light plus 5 mg melatonin （RLM）. A minimum of 48 h separated each condition, and all par- ticipants started the exposures in a rested fed condition. Results： Average （±SD） number of knee extension lifts for RL （62.0 ± 22.0） was significantly （p 〈 0.05） greater than DL （51.4 ± 14.7） and RLM （57.8 ± 22.9）. The number of RLM knee extension lifts was not significantly different from DL. Exposure to 1 h of dim light immediately prior to activity can result in a reduction in thigh muscle endurance. The decline in performance to short-term dim light exposure was similar to that found following longer-term exposure. Conclusion： It appears that light intensity can influence muscle endurance, however, at this time this effect cannot be directly related to endogenous melatonin production.展开更多
Qash Qooly valley runs parallel to Pera Magroon, Sara and Surdash anticlines, almost in SE-NW trend, and merges with the Lesser Zab River 9 km southeast to Dokan town. Before its development, it was a large basin with...Qash Qooly valley runs parallel to Pera Magroon, Sara and Surdash anticlines, almost in SE-NW trend, and merges with the Lesser Zab River 9 km southeast to Dokan town. Before its development, it was a large basin with width ranges between 2-3 km, which was filled during Pleistocene or may be Late Pliocene by different types of sediments. The presence of the calcrete on the top indicates a wet period that has lasted for a long time as indicated from the thickness of the calcrete and alluvial fan sediments. The age of Qash Qooly valley was estimated using the exposure age determination method. The type of the sediments, their thicknesses, and erosion intensity and sediments＇ dens dissection by rills were the main features used. This study concluded that the age of the basin is Pliocene--Late Pleistocene, whereas the valley started to be developed during uppermost Late Pleistocene and is still active in shifting its course.展开更多
With the purpose to determine the frequency and type of cardiac lesions in naturally exposed dogs to Trypanosoma cruzi, ninety one stray dogs, capture by the Canine and Feline Control Center （dog pound） from the mun...With the purpose to determine the frequency and type of cardiac lesions in naturally exposed dogs to Trypanosoma cruzi, ninety one stray dogs, capture by the Canine and Feline Control Center （dog pound） from the municipality of Merida, were studied. Before euthanasia, blood samples were taken to detect 72 cruzi antigens by indirect immunofluorescence antibody test and Western Blot and to detect the genome of parasite by Polymerase Chain Reaction. Immediately after euthanasia, hearts were macroscopically evaluated and a sample of the middle right atrial wall of each dog was taken for histopathological analyses. DNA was also obtained from paraffin blocks of seropositives animals with microscopic lesions to detect 72 cruzi genome. Of ninety one dogs, thirteen were seropositive. All seropositive dogs showed an association （P 〈 0.05） with lymphocytoplasmatic myocarditis. The presence of the 72 cruzi genome was also detected by PCR in cardiac septum tissue of seropositive dogs and in all the cases with microscopic lesions indicating the high pathogenicity of the local circulating strain. No association with macroscopic lesions was observed in seropositive dogs. Also, the presence of Dirofilaria immitis （D. immitis） was found in 6% of dogs evaluated. This study demonstrates a high tropism to cardiac tissue and virulence of the strains of 72 cruzi circulating in the studied dog population.展开更多
基金Project(2010CB731705)supported by the National Basic Research Program of China
文摘Cyclic thermal exposure tests of infrared heating to 800 ℃ in 120 s followed by compressed air cooling to 150 ℃ in 60 s were performed for the laser deposited Ti60A （Ti5.54Al3.38Sn3.34Zr0.37Mo0.46Si） alloy. The effects of thermal exposure cycles on length ofβphase, area fraction ofαphase and microhardness of alloy were examined by OM, SEM and EDS. The results indicate that thermal exposure cycles have significant effects on length ofβphase, area fraction ofαphase and microhardness of the alloy. The original fine basket-weaveβand 78.5%αtransform to transient wedge-likeβ, finally leaving granularβand 97.6%coarsenedαwith the increased thermal exposure cycles. The formation mechanism of coarsenedαand broken-upβmicrostructure is discussed. The alloy after 750 thermal exposure cycles has the maximum microhardness, 33.3%higher than that of the as-deposited alloy.
文摘Background： Since it has been shown that spending 18 h under dim light conditions can result in reduced handgrip endurance, it was questioned whether or not a shorter exposure to dim light （i.e., 1 h） would have similar influence upon muscular endurance. Therefore this study compared the number of weighted knee extension lifts that could be done after spending 1 h in either dim or bright light. Methods： Participants （5 women, 11 men, college students 19--26 years） performed knee extension lifts to exhaustion with a load approximating 40% of their body weight. The lifts to exhaustion were measured immediately following 1 h of exposure to each of the following three con- ditions： dark （DL）, room light （RL）, and room light plus 5 mg melatonin （RLM）. A minimum of 48 h separated each condition, and all par- ticipants started the exposures in a rested fed condition. Results： Average （±SD） number of knee extension lifts for RL （62.0 ± 22.0） was significantly （p 〈 0.05） greater than DL （51.4 ± 14.7） and RLM （57.8 ± 22.9）. The number of RLM knee extension lifts was not significantly different from DL. Exposure to 1 h of dim light immediately prior to activity can result in a reduction in thigh muscle endurance. The decline in performance to short-term dim light exposure was similar to that found following longer-term exposure. Conclusion： It appears that light intensity can influence muscle endurance, however, at this time this effect cannot be directly related to endogenous melatonin production.
文摘Qash Qooly valley runs parallel to Pera Magroon, Sara and Surdash anticlines, almost in SE-NW trend, and merges with the Lesser Zab River 9 km southeast to Dokan town. Before its development, it was a large basin with width ranges between 2-3 km, which was filled during Pleistocene or may be Late Pliocene by different types of sediments. The presence of the calcrete on the top indicates a wet period that has lasted for a long time as indicated from the thickness of the calcrete and alluvial fan sediments. The age of Qash Qooly valley was estimated using the exposure age determination method. The type of the sediments, their thicknesses, and erosion intensity and sediments＇ dens dissection by rills were the main features used. This study concluded that the age of the basin is Pliocene--Late Pleistocene, whereas the valley started to be developed during uppermost Late Pleistocene and is still active in shifting its course.
文摘With the purpose to determine the frequency and type of cardiac lesions in naturally exposed dogs to Trypanosoma cruzi, ninety one stray dogs, capture by the Canine and Feline Control Center （dog pound） from the municipality of Merida, were studied. Before euthanasia, blood samples were taken to detect 72 cruzi antigens by indirect immunofluorescence antibody test and Western Blot and to detect the genome of parasite by Polymerase Chain Reaction. Immediately after euthanasia, hearts were macroscopically evaluated and a sample of the middle right atrial wall of each dog was taken for histopathological analyses. DNA was also obtained from paraffin blocks of seropositives animals with microscopic lesions to detect 72 cruzi genome. Of ninety one dogs, thirteen were seropositive. All seropositive dogs showed an association （P 〈 0.05） with lymphocytoplasmatic myocarditis. The presence of the 72 cruzi genome was also detected by PCR in cardiac septum tissue of seropositive dogs and in all the cases with microscopic lesions indicating the high pathogenicity of the local circulating strain. No association with macroscopic lesions was observed in seropositive dogs. Also, the presence of Dirofilaria immitis （D. immitis） was found in 6% of dogs evaluated. This study demonstrates a high tropism to cardiac tissue and virulence of the strains of 72 cruzi circulating in the studied dog population.
