979 research outputs found
Photoelectric charging of partially sunlit dielectric surfaces in space
Sunlight-shadow effects may substantially alter the charging situation for a dielectric surface. The sunlight-shadow boundary tends to be the site of intense multipole electric fields. Charges on a sunlit dielectric surface have a finite effective mobility. The charge distribution tends to resemble that on a conducting surface. A boundary between a conducting and a dielectric surface may not represent a conductivity discontinuity when this boundary is sunlit; charges may migrate at a nontrivial rate across the boundary. A contracting or expanding sunlit area may experience a supercharging
Early detection of disease program: Evaluation of the cellular immune response
Surfaces of normal, cultured, and mitogen-stimulated mouse lymphoid cells were examined by scanning electron microscopy (SEM). Lymphocytes with smooth, highly villous and intermediate surfaces were observed in cell suspensions from both spleens and thymuses of normal mice and from spleens of congenitally athymic (nude) mice. Several strain-specific surface features were noted, including the spine-like appearance of microvilli on C57B1/6 lymphocytes. Although thymus cell suspensions contained somewhat more smooth cells than did spleen cell preparations, lymphocyte derivation could not be inferred from SEM examination. Studies of cells stimulated with mitogenic agents for thymus-derived lymphocytes (concanavalin A) or for bone marrow-derived lymphocytes (lipopolysaccharide) suggested that, in the mouse, development of a complex villous surface is a general concomitant of lymphocyte activation and transformation
Carter County - Community Surveys
Community surveys of Carter County written by Home Economics students from Morehead State College during the 1950s
Cost Comparison of Methyl Bromide and Sulfuryl Fluoride (ProFume®) for Fumigating Food Processing Facilities, Warehouses, and Cocoa Beans
Costs of fumigating a food processing/warehouse facility using methyl bromide and sulfuryl fluoride (ProFume®) were compared using an economic-engineering approach. The two fumigants were also compared for fumigating cocoa beans. Sulfuryl fluoride is economically feasible for cocoa beans. It is economically feasible for some, but not all, applications in food processing facilities and warehouses. Keywords: Economics, Cost, Benefit, Fumigation methyl bromide, Sulfuryl fluoride, ProFume
Changes in Achilles Tendon Thickness Following a 10 – Week Heavy Load Eccentric Exercise Program
Achilles tendinopathy (AT) is a common overuse injury in running or jumping activities where the tendon is unable to properly respond to the load. AT increases tendon thickness while decreasing stiffness and function (1).
Studies have shown that tendon properties can be positively influenced by load (5,6). Therefore, AT has typically been treated conservatively through physical therapy, with eccentric calf strengthening exercises as the focus of the treatment (2)
Nocturnal position in the Panamanian Golden Frog, Atelopus zeteki (Anura, Bufonidae), with notes on fluorescent pigment tracking
La rana dorada de Panamá, Atelopus zeteki, una especie en peligro de extinción, habita en los rÃos de los bosques lluviosos de mediana elevación del istmo panameño. Con el propósito de conocer mejor ésta especie para su conservación, decidimos determinar los sitios de descanso nocturno de estos animales, los cuales se caracterizan por ser activos durante el dÃa. SuponÃamos que los machos adultos y los juveniles podrÃan ocupar micro hábitat distintos durante la noche, basándose en las diferencias en tamaños y patrones de coloración. Los resultados presentados aquà demuestran que, al caer la noche los machos adultos trepan significativamente más alto que los juveniles y que la distancia de estos movimientos desde el punto inicial hasta la posición final de descanso es también significativamente diferente. Estos cambios de posición durante el dÃa y la noche de los machos adultos podrÃan estar relacionados con una conducta antipredatoria. Finalmente este estudio demuestra que con el uso de pigmentos fluorescentes es posible rastrear anfibios en los bosques lluviosos con habitates húmedos a mojados a través de distancias cortas a moderadas de manera exitosa.The endangered Panamanian golden frog, Atelopus zeteki, is a stream dweller of middle elevation rain forests of the Panamanian isthmus. In order to better understand this species for conservation, we set out to determine the nocturnal whereabouts of this diurnally active animal. It was expected that adult males and juveniles might occupy different nocturnal microhabitats based on differences in size, coloration and patterning. Findings presented here demonstrate that adult males climb significantly higher than juveniles at night and that movement distances to final resting positions also significantly differed. This change in diurnal and nocturnal position in adult males may be related to predator vigilance and avoidance. Lastly, this study demonstrated that individual rain forest amphibians can be successfully tracked over short to moderate distances in humid to wet environments using fluorescent pigments
Nocturnal position in the Panamanian Golden Frog, Atelopus zeteki (Anura, Bufonidae), with notes on fluorescent pigment tracking
The endangered Panamanian golden frog, Atelopus zeteki, is a stream dweller of middle elevation rain forests of the Panamanian isthmus. In order to better understand this species for conservation, we set out to determine the nocturnal whereabouts of this diurnally active animal. It was expected that adult males and juveniles might occupy different nocturnal microhabitats based on differences in size, coloration and patterning. Findings presented here demonstrate that adult males climb significantly higher than juveniles at night and that movement distances to final resting positions also significantly differed. This change in diurnal and nocturnal position in adult males may be related to predator vigilance and avoidance. Lastly, this study demonstrated that individual rain forest amphibians can be successfully tracked over short to moderate distances in humid to wet environments using fluorescent pigments. © 2007 Departamento de Ciências Biológicas
Lunar Outgassing, Transient Phenomena and The Return to The Moon, I: Existing Data
Herein the transient lunar phenomena (TLP) report database is subjected to a
discriminating statistical filter robust against sites of spurious reports, and
produces a restricted sample that may be largely reliable. This subset is
highly correlated geographically with the catalog of outgassing events seen by
the Apollo 15, 16 and Lunar Prospector alpha-particle spectrometers for
episodic Rn-222 gas release. Both this robust TLP sample and even the larger,
unfiltered sample are highly correlated with the boundary between mare and
highlands, as are both deep and shallow moonquakes, as well as Po-210, a
long-lived product of Rn-222 decay and a further tracer of outgassing. This
offers another significant correlation relating TLPs and outgassing, and may
tie some of this activity to sagging mare basalt plains (perhaps mascons).
Additionally, low-level but likely significant TLP activity is connected to
recent, major impact craters (while moonquakes are not), which may indicate the
effects of cracks caused by the impacts, or perhaps avalanches, allowing
release of gas. The majority of TLP (and Rn-222) activity, however, is confined
to one site that produced much of the basalt in the Procellarum Terrane, and it
seems plausible that this TLP activity may be tied to residual outgassing from
the formerly largest volcanic ffusion sites from the deep lunar interior. With
the coming in the next few years of robotic spacecraft followed by human
exploration, the study of TLPs and outgassing is both promising and imperiled.
We will have an unprecedented pportunity to study lunar outgassing, but will
also deal with a greater burden of anthropogenic lunar gas than ever produced.
There is a pressing need to study lunar atmosphere and its sources while still
pristine. [Abstract abridged.]Comment: 35 pages, 3 figures, submitted to Icarus. Other papers in series
found at http://www.astro.columbia.edu/~arlin/TLP
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