196,338 research outputs found
Effects of agricultural land-use on pollination services
No full textPollinators are vital for ecosystem functioning, biodiversity conservation and food production by pollinating a majority of crops and wild flowering plants. In agricultural areas, pollinators are threatened by a variety of stressors including e.g. the lack of floral resources or use of pesticides, which threatens their provision of pollination services. In this thesis, I investigated the impacts of agricultural land-use management on the provision of pollination services in agricultural areas. By measuring different indicators for pollinator health and pollination services in two important pollinator groups, bumblebees and syrphid flies, I aimed to identify key links between them and how they are affected by land-use intensification. Across all our studies, floral resource limitation was the main driver in affecting both pollinator health and pollination services. Different responses of both pollinator groups to environmental stressors emphasize the significance of considering the effects of land-use on different pollinator groups individually, e.g. by not generalizing from bees to other insect orders such as flies. For example, bumblebees were more sensitive to local land-use, while syrphid flies reacted mostly to landscape level factors. We further found that the effects of land-use on pollinator health were temporally stable across different years of sampling, showing that pollinators foraging in intensively used areas are under persistent pressure. This stability indicates that without significant changes in land-use practices, pollinators will continue to face substantial challenges in agricultural landscapes. Conservation strategies should focus on supporting flower-rich and diverse landscapes to support diverse and healthy pollinator communities. This approach not only benefits pollinators but also their provision of pollination services, which contributes to the overall functioning and productivity of agricultural ecosystems and ultimately affects human health
Dr. Duane M. Jackson, Morehouse College, July 2011
No full textThis video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States" By M. Carey.
No full text"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States: containing bried sketches of the moral and political character of those states.
By M. Carey, member of the American philosophical, and of the American Antiquarian Society, and author of The Olive Branch, Cindiciae Hibernicae, essays on banking, on political economy, and on internal improvement.
To which are now added the English editor's comments on the subject; together with Important Advice to Emigrants, and Cautions Against Impositions Practiced in the Outports
Zinsser microbiology/ Wolfgang K. Joklik; Hilda P. Willet; D. Bernerd Amos; Catherine M. Wilfert (edt)
No full textxv, 996 hal: ill; 28 c
Curved Track Analysis of FSO Link for Ground-to-Train Communications
No full textIn this work, a free space optical (FSO) link for the ground-to-train (G2T-FSO) communications is proposed. Analytical analysis is carried out for the curved rail tracks. We show that the transmitter divergence angle, the transmit power and the size of the concentration lens need to increase for the curved section of the rail track compared to the straight track. We derive the analytical expression for the received power level based on the link geometry for the case of the curved track In the worst case scenario when the curvature radius is 120 m, the transmit power at the optical base station (BS) needs to increase by over 2 dB when the concentration lens radius is increased by 5 times. Analyses also show that the received power along the track increases with the curvature radius for the same transmit power and receiver optics illustrating the effect due to link geometry. Additionally, the signal-to-noise ratio (SNR) and the bit error rate (BER) performance of the system for the curved track with different curvature radii is analysed at data rates of 10 Mbps and 100 Mbps for an additive white Gaussian noise (AWGN) channel showing a good agreement between the theoretical and the simulated BER. Finally, effect of scintillations on the G2T-FSO link performance is discussed
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Dr. Glendon Swarthout
No full textHosted by Roger M. Busfield, MSU Assistant Professor of Speech and Theater, Meet the Author is designed to introduce a general audience to a contemporary author and their work through in-depth interviews. This episode features a conversation between Dr. Glendon Swarthout, prolific author and English professor at MSU, and assistant professors Sam S. Baskett and Theodore B. Strandness
Markers and determinants of disease progression in children with HIV infection. The Pediatric AIDS Siena Workshop II.
No full textZinsser microbiology/ Wolfgang K. Joklik; Hilda P. Willet; D. Bernerd Amos; Catherine M. Wilfert (edt)
No full textxv, 996 hal: ill; 28 c
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