2,463 research outputs found
Seabed foraging by Antarctic krill: Implications for stock assessment, bentho-pelagic coupling, and the vertical transfer of iron
No full textA compilation of more than 30 studies shows that adult Antarctic krill (Euphausia superba) may frequent benthic habitats year-round, in shelf as well as oceanic waters and throughout their circumpolar range. Net and acoustic data from the Scotia Sea show that in summer 2-20% of the population reside at depths between 200 and 2000 m, and that large aggregations can form above the seabed. Local differences in the vertical distribution of krill indicate that reduced feeding success in surface waters, either due to predator encounter or food shortage, might initiate such deep migrations and results in benthic feeding. Fatty acid and microscopic analyses of stomach content confirm two different foraging habitats for Antarctic krill: the upper ocean, where fresh phytoplankton is the main food source, and deeper water or the seabed, where detritus and copepods are consumed. Krill caught in upper waters retain signals of benthic feeding, suggesting frequent and dynamic exchange between surface and seabed. Krill contained up to 260 nmol iron per stomach when returning from seabed feeding. About 5% of this iron is labile, i.e., potentially available to phytoplankton. Due to their large biomass, frequent benthic feeding, and acidic digestion of particulate iron, krill might facilitate an input of new iron to Southern Ocean surface waters. Deep migrations and foraging at the seabed are significant parts of krill ecology, and the vertical fluxes involved in this behavior are important for the coupling of benthic and pelagic food webs and their elemental repositories
Towards the Horsewoman: Performing Femininity in the American Horse Training and Riding Arenas
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Ecosystem warming increases sap flow rates of northern red oak trees
No full textOver the next century, air temperature increases up to 5 °C are projected for the northeastern USA. Because evapotranspiration strongly influences water loss from terrestrial ecosystems, the ecophysiological response of trees to warming will have important consequences for forest water budgets. We measured growing season sap flow rates in mature northern red oak (Quercus rubra L.) trees in a combined air (up to 5.5 °C above ambient) and soil (up to 1.85 °C above ambient at 6-cm depth) warming experiment at Harvard Forest, MA, USA. Through principal components analysis we found air and soil temperatures had the largest effects on rates of sap flow with relative humidity, photosynthetically active radiation and vapor pressure deficit having significant, but smaller, effects. On average, each 1 °C increase in temperature increased sap flow rates by approximately 1100 kg H2O m-2 sapwood area day-1 throughout the growing season and by 1200 kg H2O m-2 sapwood area day-1 during the early growing season. Reductions in the number of cold winter days correlated positively with increased sap flow during the early growing season (a decrease of 100 heating-degree-days was associated with a sapflow increase of approximately 5 kg H2O m-2 sapwood area day-1). Soil moisture declined with increased treatment temperatures, and each soil moisture percentage decrease resulted in a decrease in sap flow of approximately 360 kg H2O m-2 sapwood area day-1. At night, soil moisture correlated positively with sap flow. These results demonstrate that warmer air and soil temperatures in winter and throughout the growing season lead to increased sap flow rates, which could affect forest water budgets throughout the yearOrganismic and Evolutionary BiologyAccepted Manuscrip
Exhibition Season: Annual Archaeological Exhibitions in London, 1880s-1930s
No full textAnnual archaeological exhibitions were a visible symbol of archaeological research. Held mainly in London, the displays encapsulated a network of archaeologists, artists, architects and curators, and showcased the work of the first generations of trained archaeologists. The exhibition catalogues and published reviews of the displays provide a unique method for exploring the reception and sponsorship of archaeological work overseas and its promotion to a fascinated, well connected and well moneyed public. The exhibitions were a space in which conversation and networking were as important as educational enrichment. This paper analyses the social history of the “annual exhibition” in archaeology, highlighting the development and maintenance of the networks behind archaeological research, the geography of London as a way to examine influence in archaeology, and the utility of exhibitions for archaeological publicity during this period of exploration
An Estimation of the Entomological Inoculation Rate for Ifakara: A Semi-Urban Area in a Region of Intense Malaria Transmission in Tanzania.
Get PDFAn entomological study on vectors of malaria and their relative contribution to Plasmodium falciparum transmission in the semi-urban area of Ifakara, south-eastern Tanzania, was conducted. A total of 32 houses were randomly sampled from the area and light trap catches (LTC) performed in one room in each house every 2 weeks for 1 year. A total of 147 448 mosquitoes were caught from 789 LTC; 26 134 Anopheles gambiae s.l., 615 A. funestus, 718 other anophelines and 119 981 culicines. More than 60% of the total A. gambiae s.l. were found in five (0.6%) LTCs, with a maximum of 5889 caught in a single trap. Of 505 A. gambiae s.l. speciated by polymerase chain reaction, 91.5% were found to be A. arabiensis. Plasmodium falciparum sporozoite enzyme-linked immunosorbent assay tests were performed on 10 108 anopheles mosquitoes and 39 (0.38%) were positive. Entomological inoculation rate (EIR) estimates were generated using a standard method and an alternative method that allows the calculation of confidence intervals based on a negative binomial distribution of sporozoite positive mosquitoes. Overall EIR estimates were similar; 31 vs. 29 [95% confidence interval (CI): 19, 44] infectious bites per annum, respectively. The EIR ranged from 4 (95% CI: 1, 17) in the cool season to 108 (95% CI: 69, 170) in the wet season and from 54 (95% CI: 30, 97) in the east of the town to 15 (95% CI: 8, 30) in the town centre. These estimates show large variations over short distances in time and space. They are all markedly lower than those reported from nearby rural areas and for other parts of Tanzania
The post-villain: Ambiguous villain meets comic relief in Teen Wolf
No full textEllison, ER ORCiD: 0000-0002-0865-950XTelevision series, especially those in the supernatural or paranormal genres, regularly include long-lasting character arcs for characters other than the heroes – including those more villainous (see, for instance, Buffy the Vampire Slayer [1997–2003], Supernatural [2005–present] and The X-Files [1992–2002] among others). This article uses textual and character analysis to perform a close reading of Teen Wolf Season 6A (2017), in particular the characters Peter Hale and Theo Raeken. The analysis, grounded in theory regarding popular culture and villains, reveals that both characters are examples of a previously undefined villain, which we have termed the ‘post-villain’. Using examples from the text, five aspects of the post-villain are discussed with the suggestion for future research outside of Teen Wolf
Population differences in immune responses to Bacille Calmette-Guérin vaccination in infancy.
Get PDFBacille Calmette-Guérin (BCG) vaccination induces a marked increase in the interferon (IFN)-gamma response to Mycobacterium tuberculosis purified protein derivative (Mtb PPD) in UK adolescents, but not in Malawian adolescents. We hypothesized that Mtb PPD-induced IFN-gamma after BCG vaccination would be similar in infants from these 2 countries. Infants were vaccinated with BCG during the first 3-13 weeks of life. Three months after BCG vaccination, 51 (100%) of 51 UK infants had an IFN-gamma response to Mtb PPD, compared to 41 (53%) of 78 of Malawian infants, in whom responses varied according to their season of birth. We conclude that population differences in immune responses after BCG vaccination are observed among infants, as well as among young adults
Letter to Alexander M. Jackson from Abraham Rencher
No full textLetter dated November 22, 1859 from Abraham Rencher, Governor of New Mexico, to Alexander M. Jackson, Secretary of New Mexico, informing Jackson that all repairs upon the old palace, Palace of the Governors, Santa Fe, have been suspended for the season, the only item that needs to be done is the Portal in front, to be done in the Spring, soon as lumber can be procured. Rencher paid Ellison $100 for help on the palace, overseeing workers, wages, hours. HL introduction page overlaid by document. Letter in English, handwritten, 1pp/fr
Atlantic Hurricane Season of 1997
No full textThe 1997 Atlantic hurricane season is summarized and the year's tropical storms, hurricanes, and one subtropical storm are described. The tropical cyclones were relatively few in number, short lived, and weak compared to long-term climatology. Most systems originated outside the deep Tropics. Hurricane Danny was the only system to make landfall. It produced rainfall totals to near 1 m in southern Alabama and is blamed for five deaths. Hurricane Erika was responsible for the season's two other fatalities, in the coastal waters of Puerto Rico.
Corresponding author address: Dr. Edward N. Rappaport, TPC/NHC, 11691 S.W. 17th Street, Miami, FL 33165-2149
In-season vs. out-of-season: the effects of athletic participation on middle school students‟ core curricular grades, school attendance, and in-school behavior
No full textThis study examined middle school student-athletes over a three year time period, and had three key purposes. Those purposes were to reveal any differences that may exist in students’ core-curricular grades, school attendance, and in-school behavior as a result of being out-of-season from a middle school sport. The study examined ninety student-athletes, and compared the mentioned data of student-athletes while they were in-season with the same data from the marking period immediately following the conclusion of their seasons of competition. The central research questions were: (1) Is there a difference in student-athletes’ core curricular grades in-season vs. out-of-season? (2) Do student-athletes have better attendance records during their season of competition? (3) Do student-athletes have better disciplinary records during their season of competition? Three main findings resulted from this study. First, middle school student-athletes obtain significantly higher core-curricular grades during their season of competition. Second, middle school student-athletes have significantly better attendance records while their sport is in-season. Finally, middle school student-athletes have significantly better disciplinary records when their sport is in-season. These findings challenge previous research (Emmons, 1994) who found no significant differences of student-athletes’ in-season vs. out-of-season core-curricular grades. This investigation also compliments the research done by Siegenthaler (2001) who found that student-athletes had significantly better attendance records during their season of competition. This study affords educators and administrators the opportunity to understand how valuable athletic participation can be in the classroom as well as on the playing field.Ed. D.Includes bibliographical referencesby Matthew Ritchi
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