The Effect of Larval Diet and Sex on Nectar Nicotine Feeding Preferences in Manduca Sexta (Lepidoptera: Sphingidae)

The article offers information on the study conducted regarding the implication of larval diet and nectar nicotine feeding to the sexual behavior of Manduca Sexta. Researchers found that many of these lepidoptera interact with the same plant species, both herbivorous larvae and nectar-feeding adults. Moreover, they found that the said behavior paves the way to influence both pollination and herbivory in floral and foliar tissue

On the Spectroscopic Diversity of Type Ia Supernovae

A comparison of the ratio of the depths of two absorption features in the spectra of TypeIa supernovae (SNe Ia) near the time of maximum brightness with the blueshift of the deep red Si II absorption feature 10 days after maximum shows that the spectroscopic diversity of SNe Ia is multi-dimensional. There is a substantial range of blueshifts at a given value of the depth ratio. We also find that the spectra of a sample of SNe Ia obtained a week before maximum brightness can be arranged in a ``blueshift sequence'' that mimics the time evolution of the pre-maximum-light spectra of an individual SN Ia, the well observed SN 1994D. Within the context of current SN Ia explosion models, we suggest that some of the SNe Ia in our sample were delayed-detonations while others were plain deflagrations.Comment: accepted for publication in ApJ

Status of Acropora palmata Populations off the Coast of South Caicos, Turks and Caicos Islands

This study is the first detailed assessment of A. palmata populations of the Turks and Caicos Islands. A total of 203 individual colonies and 62 thickets were tagged on five shallow reefs. Depth, percentages of living tissue, recent mortality and old skeleton were estimated. Presence of disease and predatory snails was noted, and disease spread and grazing rates of the snails estimated. Colonies were found in depths of 0.2 - 4 m. Living tissue for individual colonies (75.9% ± 2.2 SE) was significantly greater than for thickets (58.6% ± 3.6) and in both cases exceeded old skeleton (individuals: 22.7% ± 2.1 SE, thickets: 38.0% ± 3.4 SE). Percentage of recent mortality was very low (individuals: 1.3% ± 0.3 SE, thickets: 3.4% ± 0.7%). We found WBD (n = 2), white pox disease a (WPDa) (n = 7) and white pox disease b (WPDb) (n = 14) with greatly varying spreading rates. The WBD infected colonies showed an atypical spread from the top of the branch towards the base. Coralliophila abbreviata and C. caribaea affected 3 .7 54.7% of the populations (grazing rate: 4.29 cm 2 /day/snail ± 1.16 SE). South Caicos’ A. palmata populations are still in good condition, though increasing human disturbances combined with disease and predatory snails may threaten these populations

Surface and bottom temperature and salinity climatology along the continental shelf off the Canadian and U.S. East Coasts

© The Author(s), 2016. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Continental Shelf Research 124 (2016): 165-181, doi:10.1016/j.csr.2016.06.005.A new hydrographic climatology has been created for the continental shelf region, extending from the Labrador shelf to the Mid-Atlantic Bight. The 0.2-degree climatology combines all available observations of surface and bottom temperature and salinity collected between 1950 and 2010 along with the location, depth and date of these measurements. While climatological studies of surface and bottom temperature and salinity have been presented previously for various regions along the Canadian and U.S. shelves, studies also suggest that all these regions are part of one coherent system. This study focuses on the coherent structure of the mean seasonal cycle of surface and bottom temperature and salinity and its variation along the shelf and upper slope. The seasonal cycle of surface temperature is mainly driven by the surface heat flux and exhibits strong dependency on latitude (r≈−0.9). The amplitude of the seasonal cycle of bottom temperature is rather dependent on the depth, while the spatial distribution of bottom temperature is correlated with latitude. The seasonal cycle of surface salinity is influenced by several components, such as sea-ice on the northern shelves and river discharge in the Gulf of St. Lawrence. The bottom salinity exhibits no clear seasonal cycle, but its spatial distribution is highly correlated with bathymetry, thus Slope Water and its intrusion on the shelf can be identified by its relatively high salinity compared to shallow, fresher shelf water. Two different regimes can be identified, especially on the shelf, separated by the Laurentian Channel: advection influences the phasing of the seasonal cycle of surface salinity and bottom temperature to the north, while in the southern region, river runoff and air-sea heat flux forcing are dominant, especially over the shallower bathymetry.Support from NSF OCE PO to Y-OK (OCE-1242989 and OCE-1435602) and SJL (OCE-1332666)

Analysis of the Type IIn Supernova 1998S: Effects of Circumstellar Interaction on Observed Spectra

We present spectral analysis of early observations of the Type IIn supernova 1998S using the general non-local thermodynamic equilibrium atmosphere code \tt PHOENIX}. We model both the underlying supernova spectrum and the overlying circumstellar interaction region and produce spectra in good agreement with observations. The early spectra are well fit by lines produced primarily in the circumstellar region itself, and later spectra are due primarily to the supernova ejecta. Intermediate spectra are affected by both regions. A mass-loss rate of order $\dot M \sim 0.0001-0.001$\msol yr$^{-1}$ is inferred for a wind speed of 100-1000 \kmps. We discuss how future self-consistent models will better clarify the underlying progenitor structure.Comment: to appear in ApJ, 2001, 54

Environmental controls on daytime net community calcification on a Red Sea reef flat

Coral growth and carbonate accumulation form the foundation of the coral reef ecosystem. Changes in environmental conditions due to coastal development, climate change, and ocean acidification may pose a threat to net carbonate production in the near future. Controlled laboratory studies demonstrate that calcification by corals and coralline algae is sensitive to changes in aragonite saturation state (Ωa), as well as temperature, light, and nutrition. Studies also show that the dissolution rate of carbonate substrates is impacted by changes in carbonate chemistry. The sensitivity of coral reefs to these parameters must be confirmed and quantified in the natural environment in order to predict how coral reefs will respond to local and global changes, particularly ocean acidification. We estimated the daytime hourly net community metabolic rates, both net community calcification (NCC) and net community productivity (NCP), at Sheltered Reef, an offshore platform reef in the central Red Sea. Average NCC was 8 ± 3 mmol m[superscript −2] h[superscript −1] in December 2010 and 11 ± 1 mmol m[superscript −2] h[superscript −1] in May 2011, and NCP was 21 ± 7 mmol m[superscript −2] h[superscript −1] in December 2010 and 44 ± 4 mmol m[superscript −2] h[superscript −1] in May 2011. We also monitored a suite of physical and chemical properties to help relate the rates at Sheltered Reef to published rates from other sites. While previous research shows that short-term field studies investigating the NCC–Ωa relationship have differing results due to confounding factors, it is important to continue estimating NCC in different places, seasons, and years, in order to monitor changes in NCC versus Ω in space and time, and to ultimately resolve a broader understanding of this relationship.National Science Foundation (U.S.) (Graduate Research Fellowship

Heat and salt balances over the northern California shelf in winter and spring

Heat and salt balances are estimated over the northern California shelf from early December 1988 through late February 1989 (winter) and from early March through early May 1989 (spring) from moored meteorological and oceanographic time series taken in 93 m of water 6.3 km from the coast. We find a winter mean offshore heat flux of 8.7 x 10⁵ W m¯¹, about a factor of 5 smaller than earlier estimates of the mean summer (upwelling season) offshore heat flux on the northern California shelf. The mean offshore heat flux is predominantly in the surface boundary layer and is balanced by an along-shelf heat flux divergence (as represented by an eddy along-shelf temperature gradient flux) and a cooling trend making the mean winter heat balance fundamentally three dimensional. In contrast to winter, the spring mean offshore heat flux of 6.4 x l0⁵ W m¯¹ is balanced by a positive air-sea heat flux of 8.3 x 10⁵ W m¯¹ which is about 80% of the mean air-sea heat flux in summer. This makes the spring mean heat budget primarily two dimensional, like the summer mean heat budget off northern California. On timescales of days the dominant terms in the fluctuating heat budget in both winter and spring are the cross-shelf heat flux and local changes in heat content. These are well correlated with each other and with the local along-shelf wind stress. The along-shelf temperature gradient flux, uncorrelated with the along-shelf wind stress, is usually weak on timescales of days. Occurrences when it is strong are interpreted as effects of mesoscale features. Mean and fluctuating cross-shelf salt fluxes provide essentially the same information as cross-shelf heat fluxes. This is not surprising in light of the strong temperature-salinity relationship on the northern California shelf