Entire DC Network | Open Access Articles | Digital Commons Network™

1,3,7-Trideacetylkhivorin, Huaping Zhang, Don Vanderveer, Xi Wang, Feng Chen, Michael J. Wargovich

Publications

The title D-seco limonoid, named 1,3,7-trideacetylkhivorin (systematic name: 14,15:21,23-diepoxy-1,3,7-trihydroxy-4,4,8-trimethyl-D-homo-24-nor-17-oxochola-20,22-diene-16-one), C₂₆H₃₆O₇, was isolated from the stem bark of African mahogany Khaya senegalensis (Meliaceae). The four fused six-membered rings adopt chair, chair, boat and half-chair conformations. The five-membered furan ring is disordered by a 180° rotation about the bond linking it to the pyran ring. The crystal structure is stabilized by strong classical O-HO hydrogen-bond interactions to form a network.

Go to article

Polyphenolic Profile And Antioxidant Activities Of Oolong Tea Infusion Under Various Steeping Conditions, Xinguo Su, Jun Duan, Yueming Jiang, Xuewu Duan, Feng Chen

Publications

The phenolic profile and antioxidant activities of oolong tea extract were investigated after tea was steeped in 90 or 100 oC water for 3 or 10 min. The extraction yield increased with increasing temperature and extended steeping time. However, higher temperature and longer time (100 oC water for 10 min) led to loss of phenolics. The aqueous extract of oolong tea (AEOT) at 100 oC for 3 min exhibited the strongest antioxidant activity. The major polyphenolic components of the AEOT were identified as (-)-epigallocatechin (EGC), (-)-epigallocatechin gallate (EGCG) and (-)-epicatechin-3-gallate (ECG). The two major catechins (EGC and EGCG) in the …

Go to article

Complete Chloroplast Genome Sequences Of Hordeum Vulgare, Sorghum Bicolor And Agrostis Stolonifera, And Comparative Analyses With Other Grass Genomes, Susanna Ashton, Seung-Bum Lee, Siri Fjellheim, Chittibabu Guda, Robert K. Jansen, Hong Luo, Jeffrey Tomkins, Odd Arne Rognli, Henry Daniell, Jihong Liu Clarke

Publications

Comparisons of complete chloroplast genome sequences of Hordeum vulgare, Sorghum bicolor and Agrostis stolonifera to six published grass chloroplast genomes reveal that gene content and order are similar but two microstructural changes have occurred. First, the expansion of the IR at the SSC/IRa boundary that duplicates a portion of the 5′ end of ndhH is restricted to the three genera of the subfamily Pooideae (Agrostis, Hordeum and Triticum). Second, a 6 bp deletion in ndhK is shared by Agrostis, Hordeum, Oryza and Triticum, and this event supports the sister relationship between the subfamilies …

Go to article

Description Of The First Chlamydopsinae (Coleoptera: Histeridae) From The Philippines, Michael S. Caterino, Alexey K. Tishechkin

Publications

The first two species of the obligate inquilinous subfamily Chlamydopsinae (Coleoptera: Histeridae) from the Philippines, Eucurtiopsis ashei (Luzon Island) and E. avis (Negros Island), are described and illustrated. Positions of the new species within the genus and potential biogeographic connection of the Philippine chlamydopsine fauna are discussed.

Go to article

Associating Larvae And Adults Of Chinese Hydropsychidae Caddiflies (Insecta:Trichoptera) Using Dna Sequences, Xin Zhou, Karl M. Kjer, John C. Morse

Publications

The utility of hydropsychid (Trichoptera:Hydropsychidae) caddisfly larvae for freshwater biomonitoring has been demonstrated, but the major impediment to its implementation has been the lack of species-level larval descriptions and illustrations. A rapid and reliable molecular protocol that also uses morphology is proposed because conventional approaches to associating undescribed larvae with adults have been slow and problematic. Male adults were identified before DNA sequence analyses were used. These identifications established morphospecies boundaries that were mapped on phylograms constructed from 2 independent gene fragments: mitochondrial cytochrome c oxidase subunit I (COI) and large subunit (28S) nuclear ribosomal DNA expansion fragment D2 (D2). …

Go to article

A Link Between Hurricane-Induced Tree Sprouting, High Stem Density And Short Canopy In Tropical Dry Forest, Skip Van Bloem, Peter G. Murphy, Ariel E. Lugo

Publications

The physiognomy of Caribbean dry forest is shorter, denser and contains a greater proportion of multi-stemmed trees than other neotropical dry forests. Our previous research, conducted after Hurricane Georges in 1998, has shown that dry forest trees sprout near the base following hurricane disturbance, even if the trees have not incurred structural damage. However, for these hurricane-induced sprouts to contribute to the physiognomy of the forest, they must grow and survive. We followed sprout dynamics and stem mortality on 1,407 stems from 1998, after Hurricane Georges, until 2005. The number of surviving sprouts and the proportion of sprouting stems decreased …

Go to article

Urban Physiology: City Ants Possess High Heat Tolerance, Michael W. Sears, Michael J. Angilletta, Robbie S. Wilson, Amanda C. Niehaus, Pedro L. Ribeiro, Carlos A. Navas

Publications

Urbanization has caused regional increases in temperature that exceed those measured on a global scale, leading to urban heat islands as much as 12°C hotter than their surroundings. Optimality models predict ectotherms in urban areas should tolerate heat better and cold worse than ectotherms in rural areas. We tested these predications by measuring heat and cold tolerances of leaf-cutter ants from South America’s largest city (São Paulo, Brazil). Specifically, we compared thermal tolerances of ants from inside and outside of the city. Knock-down resistance and chill-coma recovery were used as indicators of heat and cold tolerances, respectively. Ants from within …

Go to article

Wind Damage And Salinity Effects Of Hurricanes Katrina And Rita On Coastal Baldcypress Forests Of Louisiana, William Conner, Thomas W. Doyle, Richard H. Day, Ken W. Krauss, Christopher M. Swarzenski

Publications

The frequency of hurricane landfall in a given coastal stretch may play a more important role in the ecology of coastal forests than previously thought because of direct and indirect impacts of fallen trees and the introduction of salt water that lingers long after the storm passes. Findings show that surge events can inundate interior freshwater forests many miles from the coast and elevate soil salinities twofold to threefold. These elevated salinities may contribute to delayed mortality of certain tree species and set the stage for eventual forest decline and dieback.

Go to article

Science And The Storms: The Usgs Response To The Hurricanes Of 2005 - Chapter Six: Ecological Impacts, William Conner, Stephen Faulkner, Wylie Barrow, Brady Couvillion, Lori Randall, Michael Baldwin

Publications

Ecological impacts from the hurricanes of 2005 affected both vegetation and the animals that depend on coastal habits on land and in water. Discussed in this section are migratory birds, coastal marsh vegetation, chenier forests, coastal floodplain forests, mangrove forests, estuaries, and the endangered manatee.

Go to article

Conservation And Use Of Coastal Wetland Forests In Louisiana, William Conner, Stephen P. Faulkner, Jim L. Chambers, Richard F. Keim, John W. Day, Emile S. Gardiner, Melinda S. Hughes, Sammy L. King, Kenneth W. Mcleod, Craig A. Miller, J Andrew Nyman, Gary P. Shaffer

Publications

The natural ecosystems of coastal Louisiana reflect the underlying geomorphic processes responsible for their formation. The majority of Louisiana's wetland forests are found in the lower reaches of the Mississipp Alluvial Valley and the Deltaic Plain. The sediments, water, and energy of the Mississippi River have shaped the Deltaic Plain as natural deltas have been formed and abandoned over the last 5,000 years (Coleman et al. 1998). During the regressive or constructional phase of the delta cycle, the system is dominated by freshwater riverine inputs with the formation of corresponding freshwater marshes and swamps, which then deteriorate during the marine-dominated …

Go to article

Moistened Seeds Increase Rodent Trap Success, Michael W. Sears, John C. Tull

Publications

Seed moisture has been shown to influence the rates of seed cache removal by rodents. Although the precise mechanism is not known, this knowledge might prove useful in field applications. We examined whether moistened bait would increase trap success in desert rodent populations. We placed traps 15 m apart in grids within a 500-ha study area and randomly baited traps with either dry or moistened seeds. We found that traps baited with moistened seeds had 34.9% higher success than traps baited with dry seeds (n = 190, Χ² = 5.389, df = 1, P = 0.020). Our results …

Go to article

Digital Commons Network^™

Full-Text Articles in Entire DC Network

1,3,7-Trideacetylkhivorin, Huaping Zhang, Don Vanderveer, Xi Wang, Feng Chen, Michael J. Wargovich

Publications

Polyphenolic Profile And Antioxidant Activities Of Oolong Tea Infusion Under Various Steeping Conditions, Xinguo Su, Jun Duan, Yueming Jiang, Xuewu Duan, Feng Chen

Publications

Publications

Description Of The First Chlamydopsinae (Coleoptera: Histeridae) From The Philippines, Michael S. Caterino, Alexey K. Tishechkin

Publications

Associating Larvae And Adults Of Chinese Hydropsychidae Caddiflies (Insecta:Trichoptera) Using Dna Sequences, Xin Zhou, Karl M. Kjer, John C. Morse

Publications

A Link Between Hurricane-Induced Tree Sprouting, High Stem Density And Short Canopy In Tropical Dry Forest, Skip Van Bloem, Peter G. Murphy, Ariel E. Lugo

Publications

Urban Physiology: City Ants Possess High Heat Tolerance, Michael W. Sears, Michael J. Angilletta, Robbie S. Wilson, Amanda C. Niehaus, Pedro L. Ribeiro, Carlos A. Navas

Publications

Wind Damage And Salinity Effects Of Hurricanes Katrina And Rita On Coastal Baldcypress Forests Of Louisiana, William Conner, Thomas W. Doyle, Richard H. Day, Ken W. Krauss, Christopher M. Swarzenski

Publications

Science And The Storms: The Usgs Response To The Hurricanes Of 2005 - Chapter Six: Ecological Impacts, William Conner, Stephen Faulkner, Wylie Barrow, Brady Couvillion, Lori Randall, Michael Baldwin

Publications

Conservation And Use Of Coastal Wetland Forests In Louisiana, William Conner, Stephen P. Faulkner, Jim L. Chambers, Richard F. Keim, John W. Day, Emile S. Gardiner, Melinda S. Hughes, Sammy L. King, Kenneth W. Mcleod, Craig A. Miller, J Andrew Nyman, Gary P. Shaffer

Publications

Moistened Seeds Increase Rodent Trap Success, Michael W. Sears, John C. Tull

Publications