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251.
Pasupathy AN Bialczak RC Martinek J Grose JE Donev LA McEuen PL Ralph DC 《Science (New York, N.Y.)》2004,306(5693):86-89
We measured Kondo-assisted tunneling via C60 molecules in contact with ferromagnetic nickel electrodes. Kondo correlations persisted despite the presence of ferromagnetism, but the Kondo peak in the differential conductance was split by an amount that decreased (even to zero) as the moments in the two electrodes were turned from parallel to antiparallel alignment. The splitting is too large to be explained by a local magnetic field. However, the voltage, temperature, and magnetic field dependence of the signals agree with predictions for an exchange splitting of the Kondo resonance. The Kondo effect leads to negative values of magnetoresistance, with magnitudes much larger than the Julliere estimate. 相似文献
252.
Hauksson E Jones LM Davis TL Hutton LK Williams P Bent AL Brady AG Reasenberg PA Michael AJ Yerkes RF Etheredge E Porcella RL Johnston MJ Reagor G Stover CW Bufe CG Cranswick E Shakal AK 《Science (New York, N.Y.)》1988,239(4846):1409-1412
The Whittier Narrows earthquake sequence (local magnitude, M(L) = 5.9), which caused over $358-million damage, indicates that assessments of earthquake hazards in the Los Angeles metropolitan area may be underestimated. The sequence ruptured a previously unidentified thrust fault that may be part of a large system of thrust faults that extends across the entire east-west length of the northern margin of the Los Angeles basin. Peak horizontal accelerations from the main shock, which were measured at ground level and in structures, were as high as 0.6g (where g is the acceleration of gravity at sea level) within 50 kilometers of the epicenter. The distribution of the modified Mercalli intensity VII reflects a broad north-south elongated zone of damage that is approximately centered on the main shock epicenter. 相似文献
253.
Extreme lymphocytosis with myelomonocytic morphology in a horse with diffuse large B‐cell lymphoma 下载免费PDF全文
Kristina Meichner Jessica R. Durrant Carol B. Grindem Babetta A. Breuhaus Peter F. Moore Jennifer A. Neel Keith E. Linder Luke B. Borst Jonathan E. Fogle Jaime L. Tarigo 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2017,46(1):64-71
An 11‐year‐old, 443‐kg Haflinger mare was presented to the North Carolina State University Veterinary Teaching Hospital with a 2‐week history of lethargy and a 3‐day duration of anorexia, pyrexia, tachycardia, and ventral edema. Severe pitting edema, peripheral lymphadenopathy, and a caudal abdominal mass were noted on physical examination. An extreme leukocytosis (154.3 × 103/μL) and microscopic hematologic findings suggestive of myelomonocytic leukemia were observed. Serum protein electrophoresis revealed a monoclonal gammopathy and urine protein electrophoresis revealed a monoclonal light chain proteinuria. Necropsy and histopathology confirmed widespread neoplastic infiltration in many organs with a heterogenous population of cells; there was no apparent evidence of bone marrow involvement. Immunohistochemistry confirmed presence of a majority of B cells with a limited antigen expression, admixed with a lower number of T cells. Molecular clonality analysis of IgH2, IgH3, and kappa‐deleting element (KDE, B cell) on whole blood and KDE on infiltrated tissues revealed clonal rearrangements, and the KDE intron clones that amplified in blood and in infiltrated tissue were identical. In contrast, the clonality analysis of T‐cell receptor γ revealed no clonality on blood cells and infiltrated tissues. In conjunction with the histopathologic changes, the lesion was interpreted to be composed of neoplastic B cells with a reactive T‐cell population. Polymerase chain reaction testing for equine herpes virus 5 was negative. The final diagnosis was diffuse large B‐cell lymphoma with a marked hematogenous component. 相似文献
254.
Mayer L. Calma Joannes Luke B. Asis Paul Mark B. Medina 《Water, air, and soil pollution》2018,229(5):159
Erythromycin is one of the most widely used antibiotics globally and is considered an emerging contaminant in wastewaters and environmental waters. The egg, larval, and pupal stages of the dengue vector Aedes aegypti L. reside and develop in aquatic environments. These mosquito stages may be exposed to compounds in the water, such as erythromycin. Aquatic stages of Ae. aegypti were reared in different concentrations of erythromycin which resulted in significant delay and decrease in eclosion of eggs and pupation of larvae (P?<?0.05). Moreover, emergence of adults from pupae, larval survival, and adult female fecundity significantly decreased (P?<?0.05). A few occurrences of hypopigmentation in larvae and blisters in adult mosquitoes were also observed. Interestingly, second-generation eggs, which were laid by adult female mosquitoes exposed to erythromycin during their aquatic stages, did not exhibit decreased levels of eclosion in the presence of erythromycin. These results reveal that long-term erythromycin exposure disrupts the Ae. aegypti life cycle by decreasing survival and delaying progression throughout different life stages. However, this study demonstrates that Ae. aegypti can rapidly acquire significant tolerance to the emerging environmental contaminant erythromycin within two generations. 相似文献