Theoretical investigation of liquid water injection into the shock layer of a reentry vehicle

Mathematical model for flow field of liquid spray injected into supersonic air streaming past blunt bod

Post-fledging ecology and survival of neotropical migratory songbirds on a managed Appalachian forest

During the post-fledging period, some juvenile songbirds appear to require early successional habitats at some level, suggesting that disturbance (whether natural or anthropogenic) in the landscape is important. Previous studies of juvenile Wood Thrushes (Hylocichla mustelina) have found them in early successional areas in which adults do not nest. My objective was to determine how juvenile Wood Thrushes used areas harvested through various silvicultural techniques within a forested landscape. I examined settled areas, habitat use, survival, and daily movements of 55 radio-tagged juvenile Wood Thrushes on a managed forest in the central Appalachian mountains of West Virginia during 2004 to 2005.;I tagged individuals as nestlings and as juveniles, and radio-tracked birds in the natal and post-natal period. I used Global Positioning Systems to record the location of each bird on a daily basis and sampled habitat variables at these locations. All locations were assigned to one of three landcovers (mature forest, sawtimber harvests, and early successional areas) on a digitized map of the study site. I examined the proportion of daily locations within each landcover. I measured the size of harvests and related size and age to use by juvenile Wood Thrushes.;Once independent from adults, most individuals preferred early successional areas, in particular large, older clearcuts, \u3e13-ha in size and 7-11 years post harvest. Overall, radio-tagged Wood Thrushes tended to move from open areas to those with a denser understory as they transitioned from being dependent on adults to being independent. Survival was similar among cover types ( natal: P = 0.7, mature forest 91%, sawtimber harvest 80%, early successional area 88%; post-natal: 100% among all cover types).;Radio-tagged juvenile Wood Thrushes on my study remained in the natal areas approximately 3 weeks before moving to post-natal sites. Similar to other studies, some individuals were located in up to 4 separate post-natal sites prior to migration or transmitter battery failure. Sizes of and duration within settled areas were similar to those documented in previous studies but distances between settled sites were shorter (natal to initial post-natal: x = 760 m; initial to subsequent: x = 930 m), as were daily movements between consecutive locations, suggesting juvenile Wood Thrushes on my study site did not need to move long distances to find suitable habitat. Among first post-natal settled areas occupied at least 5 days in which ≥80% of locations were within one cover type, settled areas were smallest in early successional areas (0.8 ha), intermediate in mature forest (1.0 ha), and largest in sawtimber harvests (2.8 ha) ( P = 0.01); however, settled areas within sawtimber harvests averaged smallest among subsequent settled areas with this criteria.;I examined mist-net captures of songbirds between two silvicultural methods that create early-successional patches, clearcuts and deferment cuts. In late-July and late-August 2004 and 2005, I sampled three clearcuts and three deferment cuts similar in size (14.7--16.2 ha) and age (5--8 years) on my study site. No overall differences (P \u3e 0.05) in abundance, species richness, or diversity were detected between the two treatments for adult or juvenile captures. Of the two species with the highest captures, significantly more juvenile Hooded Warblers (Wilsonia citrina) were captured (P \u3c 0.05) in clearcuts than in deferment cuts, while juvenile Chestnut-sided Warblers (Dendroica pensylvanica ) were captured more often in deferment cuts (P \u3c 0.05). Early successional patches are important in the post-fledging ecology of Wood Thrushes as well as other migratory songbirds. My results do not indicate clearcuts or deferment cuts are more favorable to all birds, rather each treatment was important to at least one guild or species. Thus, both harvest types appear suitable for use by land managers interested in creating early successional habitats for songbirds

The effect of the Wilson Reading Program on spelling skills in an inclusive sixth grade setting

This study examined the use of the Wilson Reading program as a method for instructing spelling rules and principles in an inclusive sixth grade setting. The subjects included eighteen sixth grade students, four special education and fourteen regular education students. Post testing results indicated that in 76% of all the students there was an increase of approximately one year in spelling ability. Two of the four special education students had an increase in age appropriate ability, with the two remaining special education students decreasing in grade equivalence

Species composition and seasonal abundance of Aphodiine dung beetles (Coleoptera: Scarabaeidae) in dung from ivermectin-treated and nontreated cattle

Aphodiine beetles were collected from the dung of ivermectin-treated and nontreated pastured cattle during the spring and summer months of 1993 and 1994. Seven aphodiine species in the two genera Aphodius and Ataenius were found in both ivermectin-contaminated and noncontaminated dung in both years. In 1993, over 8,200 aphodiine beetles were collected, and approximately 3,000 aphodiine beetles were collected in 1994. The percentages of the total collected numbers for each species in 1993 and 1994, respectively, were: Aphodius haemorrhoidalis 83.16% and 64.90%; Aphodius lividus 3.88% and 2.70%, Ataenius platensis and Ataenius spretulus (combined together in 1993) 7.24%; Ataenius platensis 0.07% (1994); Ataenius spretulus 1.37% (1994); Aphodius fimetarius 1.27% and 5.93%; Aphodius stercorosus 2.67% and 5.67%; and Aphodius erraticus 1.78% and 19.37%. About twice as many specimens were collected in ivermectin-contaminated dung (66.26%) as compared to noncontaminated dung (33.74%) in 1993, and the following year twice as many were again collected in ivermectin-contaminated dung (67.76%) as compared to noncontaminated dung (32.24%). Statistical analysis indicates that ivermectin itself did not affect the densities of individual species in either dung type. However, in 1993 the combined data of the three most abundant species (Aphodius haemorrhoidalis, A. lividus, and Ataenius platensis and A. spretulus added together) showed they were significantly more abundant in ivermectin-contaminated dung, but the combined data of the three most abundant species collected in 1994 (Aphodius haemorrhoidalis, A. fimetarius, and A. erraticus) show no significant differences between densities in either dung type. Statistical analysis of the combined influence of treatment and the week in which samples were collected post-treatment are presented and discussed. Seasonal distributions in 1993 and 1994 are presented for 6 of the 7 aphodiine species (except Ataenius platemis), based on the numbers of specimens collected in noncontaminated dung. In addition, the potential impact of ivermectin treatment on aphodiine beetles is discussed

Pre-determining the location of electromigrated gaps by nonlinear optical imaging

In this paper we describe a nonlinear imaging method employed to spatially map the occurrence of constrictions occurring on an electrically-stressed gold nanowire. The approach consists at measuring the influence of a tightly focused ultrafast pulsed laser on the electronic transport in the nanowire. We found that structural defects distributed along the nanowire are efficient nonlinear optical sources of radiation and that the differential conductance is significantly decreased when the laser is incident on such electrically-induced morphological changes. This imaging technique is applied to pre-determined the location of the electrical failure before it occurs.Comment: 3 figure

Phosphorylation of Akt and ERK1/2 Is Required for VEGF-A/VEGFR2-Induced Proliferation and Migration of Lymphatic Endothelium

There is growing evidence that vascular endothelial growth factor-A (VEGF-A), a ligand of the receptor tyrosine kinases VEGFR1 and VEGFR2, promotes lymphangiogenesis. However, the underlying mechanisms by which VEGF-A induces the growth of lymphatic vessels remain poorly defined. Here we report that VEGFR2, not VEGFR1, is the primary receptor regulating VEGF-A-induced lymphangiogenesis. We show that specific inhibition of VEGF-A/VEGFR2 signaling with the fully human monoclonal antibody r84 significantly inhibits lymphangiogenesis in MDA-MB-231 tumors. In vitro experiments with primary human dermal lymphatic endothelial cells (LECs) demonstrate that blocking VEGF-A activation of VEGFR2, not VEGFR1, significantly inhibits VEGF-A-induced proliferation and migration of LECs. We show that VEGF-A stimulation of LECs leads to the phosphorylation of VEGFR2 (Tyr 951, 1054, 1059, 1175, and 1214) which subsequently triggers PKC dependent phosphorylation of ERK1/2 and PI3-K dependent phosphorylation of Akt. Additionally, we demonstrate that inhibitors that suppress the phosphorylation of ERK1/2 and Akt significantly block VEGF-A- induced proliferation and migration of LECs. Together, these results shed light on the mechanisms regulating VEGF-A-induced proliferation and migration of LECs, reveal that VEGFR2 is the primary signaling VEGF-A receptor on lymphatic endothelium, and suggest that therapeutic agents targeting the VEGF-A/VEGFR2 axis could be useful in blocking the pathological formation of lymphatic vessels

VIDEO SURVEILLANCE OF NESTING WHOOPING CRANES

The primary objective of the whooping crane (Grus americana) recovery plan is to establish and maintain 3 selfsustaining wild populations, 1 being a non-migratory Florida population. From 1993 to 2005, we released 289 captive cranes in central Florida, with 31 surviving as of 1 June 2008. From 1995 to 2008 we monitored 68 nests of the Florida population; from those, only 32 chicks hatched and 9 fledged. It often was not apparent why nests failed, and it was not practical to conduct labor-intensive observations at nests; therefore, we collected behavioral data using 12-volt VHS video surveillance cameras at 13 nests from 2000 to 2008. We positioned cameras and time-lapse video recorders 200-500 m from each nest. We programmed 1-3 days/tape of recording to occur from 1 hour before sunrise to 1 hour after sunset. Seven of 13 nests were successful in hatching chicks, while the remainder failed during the incubation period. Relevant events recorded on the videotapes included: incubation durations, frequency of adults switching off during incubation, frequency of standing and egg turning, duration eggs were not incubated while adults were away, and possible causes of nest failure. Summary statistics relating to these behaviors and also to their possible implications regarding nest survival will be discussed. Video surveillance was a valuable tool for the efficient gathering of behavioral data at whooping crane nests