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2012

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Articles 6091 - 6120 of 6458

Full-Text Articles in Life Sciences

Microtaxonomy Of Fragmenting Enchytraeus Species Using Molecular Markers, With A Comment On Species Complexes In Enchytraeids, Rut Collado, Eva Hass-Cordes, Ruediger Schmelz Jan 2012

Microtaxonomy Of Fragmenting Enchytraeus Species Using Molecular Markers, With A Comment On Species Complexes In Enchytraeids, Rut Collado, Eva Hass-Cordes, Ruediger Schmelz

Turkish Journal of Zoology

Populations of Enchytraeus that reproduce by fragmentation are distributed worldwide, but their species-level taxonomy is unresolved because morphological differences are inconclusive. Therefore, we compared the isozyme and RAPD-PCR patterns of 5 populations of fragmenting enchytraeids from widely distant localities (Japan, Iran, Greece, and Brazil). Among these populations, 3 were identified (E. japonensis, E. bigeminus, and E. dudichi) and 2 were unidentified. Multiple isozyme bands suggested polyploidy in all investigated populations. In all RAPD-PCR algorithms except 1, the fragmenting group formed a cluster separate from 2 nonfragmenting Enchytraeus species. All 5 populations were clearly separable on the levels of protein and …

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Checklist Of Questidae (Clitellata) And Aeolosomatidae (Oligochaeta) From South America, Martin Lindsey Christoffersen Jan 2012

Checklist Of Questidae (Clitellata) And Aeolosomatidae (Oligochaeta) From South America, Martin Lindsey Christoffersen

Turkish Journal of Zoology

The faunistic assemblage of basal clitellates in South America presently has 2 marine species (Questa media Westheide, 1981 and Aeolosoma maritimum dubiosum Westheide & Schmidt, 1974), and 15 species of freshwater aeolosomatids: A. aureum Marcus, 1944; A. beddardi Michaelsen, 1900; A. corderoi Du Bois-Reymond Marcus, 1944; A. evelinae Marcus, 1944; A. flavum Stolc, 1903; A. gertae Marcus, 1944; A. headleyi Beddard, 1888; A. hemprichi Ehrenberg, 1831; A. hyalinum Bunke, 1967; A. marcusi Van der Land, 1971; A. sawayai Marcus, 1944; A. travancorense Aiyer, 1926; A. variegatum Vejdovsky, 1884; and A. viride Stephenson, 1911, and Hystricosoma pictum Schmarda, 1861, species inquirenda. …

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About The Scientific Names Of Paraphyletic Taxa, Tarmo Timm Jan 2012

About The Scientific Names Of Paraphyletic Taxa, Tarmo Timm

Turkish Journal of Zoology

The 'naturality' of monophyletic taxa in comparison with that of paraphyletic ones is discussed, with examples from Clitellata. Regular scientific names for paraphyletic taxa are inevitable in a workable biological classification.

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Spatial And Temporal Variation Of Echinoderm Assemblages From Soft Bottoms Of The Çanakkale Strait (Turkish Strait System) With A Taxonomic Key Of The Genus Amphiura (Echinodermata: Ophiuroidea), Herdem Aslan Ci̇hangi̇r, Maria Antonietta Pancucci-Papadopoulou Jan 2012

Spatial And Temporal Variation Of Echinoderm Assemblages From Soft Bottoms Of The Çanakkale Strait (Turkish Strait System) With A Taxonomic Key Of The Genus Amphiura (Echinodermata: Ophiuroidea), Herdem Aslan Ci̇hangi̇r, Maria Antonietta Pancucci-Papadopoulou

Turkish Journal of Zoology

This study deals with the structure of echinoderm assemblages and their relationships with the biotic and abiotic conditions in the Çanakkale Strait in 2006 and 2007. A total of 25 echinoderm species were found, 4 species of which [Amphiura securigera (Düben & Koren, 1846); Amphiura lacazei Guille, 1976; Amphiura cherbonnieri Guille, 1972; and Thyone fusus (O.F. Müller, 1776)] were new records for Turkish fauna; 1 species [Ophiopsila annulosa (M. Sars, 1859)] was new for the Turkish Strait System; and 22 species were first reports for the Çanakkale Strait. Echinocyamus pusillus (O.F. Müller, 1776), Amphipholis squamata (Delle Chiaje, 1829), and Ophiothrix …

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Helminth Parasites Of The Lemon-Yellow Tree Frog, Hyla Savignyi (Hylidae), From Turkey, Hi̇kmet Sami̇ Yildirimhan, Nurhan Sümer, Sezen İncedoğan, Charles Robert Bursey Jan 2012

Helminth Parasites Of The Lemon-Yellow Tree Frog, Hyla Savignyi (Hylidae), From Turkey, Hi̇kmet Sami̇ Yildirimhan, Nurhan Sümer, Sezen İncedoğan, Charles Robert Bursey

Turkish Journal of Zoology

Forty lemon-yellow tree frogs, Hyla savignyi, collected from Kırıkhan, Turkey (25 in April 2009, 15 in April 2010), were examined for helminths, and 21 frogs were found to be infected. One species of Monogenea (Polystoma integerrimum), 3 species of Digenea (Diplodiscus subclavatus, Halipegus kessleri, and Pleurogenoides medians), 1 species of Cestoda (Nematotaenia dispar), and 2 species of Nematoda (Aplectana brumpti and Cosmocerca commutata) were found. Hyla savignyi represents a new host record for Polystoma integerrimum, Diplodiscus subclavatus, Halipegus kessleri, Pleurogenoides medians, Aplectana brumpti, and Cosmocerca commutata.

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Two New Records Of Myxobolus Bütschli, 1882 (Myxozoa, Myxosporea, Myxobolidae) Species From Turkey, Argun Aki̇f Özak, İbrahi̇m Demi̇rkale, İbrahi̇m Cengi̇zler Jan 2012

Two New Records Of Myxobolus Bütschli, 1882 (Myxozoa, Myxosporea, Myxobolidae) Species From Turkey, Argun Aki̇f Özak, İbrahi̇m Demi̇rkale, İbrahi̇m Cengi̇zler

Turkish Journal of Zoology

Two different myxosporean fish parasites (Myxobolus episquamalis Egusa, Maeno & Sorimachi, 1990 and Myxobolus ichkeulensis Bahri & Marques, 1996) are reported based on samples found on the scales and gill arches of flathead mullet (Mugil cephalus) captured from Çamlık Lagoon, located on the northeastern Mediterranean coast of Turkey. Both parasites were found for the first time on flathead mullet from the Turkish coasts. In addition to the data concerning spore morphology and the dimensions of both species, new additional taxonomic observations are presented. Furthermore, asynchronous polar capsule maturation was observed in transmission electron microscope images of both species.

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Parasitic Hymenoptera Reared From The Insects On Heracleum Platytaenium Boiss. (Apiaceae) With New Faunistic And Biological Records, Erhan Koçak, Mustafa Özdemi̇r Jan 2012

Parasitic Hymenoptera Reared From The Insects On Heracleum Platytaenium Boiss. (Apiaceae) With New Faunistic And Biological Records, Erhan Koçak, Mustafa Özdemi̇r

Turkish Journal of Zoology

Some parasitic hymenopterans were reared from their host insects found on the stems and branches of Heracleum platytaenium Boiss., which contains furanocoumarins that are insect repellents and suppress growth in some species. Plant materials with insects were collected from the vicinity of Kızılcahamam in Ankara Province in July-September 2008. The parasitoids (Hymenoptera) and their hosts were Didyctium brunnea (Belizin) (Eucolidae) from puparia of Lasiambia albidipennis (Strobl) (Diptera: Chloropidae), Pronotalia carlinarum (Szelenyi & Erdos) (Eulophidae) and Homoporus febriculosus (Girault) (Pteromalidae) from puparia of Melanagromyza heracleana Zlobin (Diptera: Agromyzidae), and Baryscapus crassicornis (Erdos) (Eulophidae) from larvae, pupae, and adults of Lixus nordmanni …

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Aspects Of Biology Of The Deep-Water Pandalid Shrimp Plesionika Martia (A. Milne-Edwards, 1883) From Sığacık Bay (Eastern Mediterranean), Cengi̇z Koçak, Murat Özbek, Zafer Tosunoğlu Jan 2012

Aspects Of Biology Of The Deep-Water Pandalid Shrimp Plesionika Martia (A. Milne-Edwards, 1883) From Sığacık Bay (Eastern Mediterranean), Cengi̇z Koçak, Murat Özbek, Zafer Tosunoğlu

Turkish Journal of Zoology

Some aspects concerning the reproduction, growth, and population dynamics of Plesionika martia were studied. Individuals were collected monthly between May 2008 and April 2009 during surveys conducted using a commercial trawl vessel. Samples were collected from Sığacık Bay (Aegean Sea, eastern Mediterranean) at depths ranging from 494 to 550 m. A total of 2110 individuals (766 males and 1344 females) were caught during these monthly surveys. The carapace length (CL) of the males ranged from 12.4 to 22.1 mm, and in females the CL ranged between 11.5 and 24.9 mm. The values of both CL and weight in females consistently …

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The Seasonality Of Group Size And Group Composition Of Sand Partridge (Ammoperdix Heyi Heyi Temminck, 1825) In The Ibex Reserve, Saudi Arabia, Torsten Wronski Jan 2012

The Seasonality Of Group Size And Group Composition Of Sand Partridge (Ammoperdix Heyi Heyi Temminck, 1825) In The Ibex Reserve, Saudi Arabia, Torsten Wronski

Turkish Journal of Zoology

The seasonality of group size and composition in sand partridges was studied at the Ibex Reserve in central Saudi Arabia. Mean group size and flock encounter rate were significantly related to rainfall and temperature. During winter and the breeding season (March to April), the encounter rate on the valley floors was distinctly lower than that observed during summer. Although encounter rates did not differ significantly between valleys, sand partridges were more likely to be encountered in narrow, stony valleys. Correcting for valley width, encounter rates did not differ between valleys. Male and female encounter rates were constant throughout the reserve, …

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Nucleolar Organizer Regions In Mesocricetus Brandti (Nehring, 1898) (Mammalia: Rodentia) From The Yozgat And Tokat Provinces Of Turkey, Nursel Baydemi̇r Jan 2012

Nucleolar Organizer Regions In Mesocricetus Brandti (Nehring, 1898) (Mammalia: Rodentia) From The Yozgat And Tokat Provinces Of Turkey, Nursel Baydemi̇r

Turkish Journal of Zoology

Mesocricetus brandti possesses a diploid chromosome number of 2n = 42, a fundamental number of NF = 82, and a fundamental number of autosomal arms of NFa = 78. The chromosome set consists of 17 meta-submetacentric pairs, 2 subtelocentric pairs, and 1 acrocentric pair. The X chromosome is large and metacentric while the Y is medium-sized and metacentric. The nucleolar organizer regions were located at the telomeric region of 7 biarmed autosomes and at the centromeric region of 1 acrocentric autosome.

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New Locality Records Of The Snake-Eyed Lizard, Ophisops Elegans Ménétriés, 1832 (Squamata: Lacertidae), In The Western Black Sea Region Of Anatolia, Mehmet Zülfü Yildiz, Bahadir Akman, Bayram Göçmen Jan 2012

New Locality Records Of The Snake-Eyed Lizard, Ophisops Elegans Ménétriés, 1832 (Squamata: Lacertidae), In The Western Black Sea Region Of Anatolia, Mehmet Zülfü Yildiz, Bahadir Akman, Bayram Göçmen

Turkish Journal of Zoology

We report 18 specimens of Ophisops elegans from Kastamonu and Sinop provinces in the western Black Sea region of Anatolia. Previously, the northernmost known locality for O. elegans in Anatolia was Sinop Province. These new records extend the known distribution area of the species and fill the gaps in the distribution range of the species in the Black Sea region. The specimens were compared with the geographically closest subspecies, O. e. centralanatoliae from Ulukışla, Niğde. On the basis of pholidosis, coloration, and pattern, the new specimens can be included in the subspecies O. e. centralanatoliae.

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A Preliminary Study On The Length-Weight Relationship Of Sacura Boulengeri (Heemstra, 1973) From Indian Waters, Kinattumkara Bineesh, Sebastine Manju, Kallivalappil Akhilesh, Gopalakrishna Pillai Jan 2012

A Preliminary Study On The Length-Weight Relationship Of Sacura Boulengeri (Heemstra, 1973) From Indian Waters, Kinattumkara Bineesh, Sebastine Manju, Kallivalappil Akhilesh, Gopalakrishna Pillai

Turkish Journal of Zoology

Sacura boulengeri (Heemstra, 1973) is a rare serranid fish (Subfamily: Anthiinae) having very disjunct distribution in the western Indian Ocean. The rarity of the species is evident from earlier reports and, so far, no related studies on the species have been published except on taxonomy and distributional records. In the present investigation, the length-weight relationship of Sacura boulengeri was estimated to be W = 0.0777 × L2.690 (with 95% confidence intervals for b and r2). An analysis of the stomach contents revealed that sergestid shrimps and copepods were the major food items of the diet.

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The Conservation Genetics Of Three Cave-Dwelling Bat Species In Southeastern Europe And Anatolia, İbrahi̇m Raşi̇t Bi̇lgi̇n Jan 2012

The Conservation Genetics Of Three Cave-Dwelling Bat Species In Southeastern Europe And Anatolia, İbrahi̇m Raşi̇t Bi̇lgi̇n

Turkish Journal of Zoology

Genetic data from populations are currently being used in order to assess the conservation status of various species. In this study, the conservation implications of the genetic structure of 3 cave-dwelling bat species in southeastern Europe and Anatolia are discussed. These species are the greater horseshoe bat (Rhinolophus ferrumequinum), the bent-winged bat (Miniopterus schreibersii), and the long-fingered bat (Myotis capaccinii). The conservation status of the species is evaluated using 3 conservation unit approaches, specifically evolutionarily significant unit and management unit definitions and population aggregation analysis. These approaches are implemented simultaneously for the first time for any species in Turkey, through …

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Spatial And Temporal Variations In The Species Composition And Abundance Of Benthic Molluscs Along 4 Rocky Shores Of Karachi, Solaha Rahman, Sohail Barkati Jan 2012

Spatial And Temporal Variations In The Species Composition And Abundance Of Benthic Molluscs Along 4 Rocky Shores Of Karachi, Solaha Rahman, Sohail Barkati

Turkish Journal of Zoology

A total of 97 species of macromolluscs were collected from 4 rocky beaches (Manora, Buleji, Nathiagali, and Cape Monze) along the Karachi coast from December 1993 to December 1995. More species were recorded from Buleji (68) and Manora (63) than from Nathiagali (55) and Cape Monze (57). Gastropods dominated at all 4 of the sites studied. Four species were commonly abundant at all 4 sites: Turbo coronatus, Nerita albicilla, Morula granulata, and Cerithium rubus. The average number of species decreased with an increase in the tidal heights at Manora, Buleji, and Nathiagali, whereas this was greater in the high tidal …

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The Land Snail Fauna Of Mut District (Mersin Province, Turkey), Ümi̇t Kebapçi, Mehmet Zeki̇ Yildirim, İskender Gülle, Mustafa Öztop, Duygu Ceren Çağlan Jan 2012

The Land Snail Fauna Of Mut District (Mersin Province, Turkey), Ümi̇t Kebapçi, Mehmet Zeki̇ Yildirim, İskender Gülle, Mustafa Öztop, Duygu Ceren Çağlan

Turkish Journal of Zoology

The land snail fauna of the Mut District was surveyed during the spring (April-May) of 2008. A total of 31 species and subspecies-9 (29%) of them endemics-belonging to 26 genera and 14 families were determined from 41 localities. Dominant families were Enidae, Orculidae, and Hygromiidae. Humidity, vegetation, and habitat type were the determinants of species richness in the study area. Species composition, according to cluster and multivariate analyses, was also found to be affected by the altitude factor.

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Zooplankton Fauna Of Lake İznik (Bursa, Turkey), Meral Apaydin Yağci, Mustafa Ruşen Ustaoğlu Jan 2012

Zooplankton Fauna Of Lake İznik (Bursa, Turkey), Meral Apaydin Yağci, Mustafa Ruşen Ustaoğlu

Turkish Journal of Zoology

In the present study the zooplankton fauna of Lake İznik (Bursa) was investigated during January-December 2006. A total of 54 taxa-35 taxa from rotifers, 14 taxa from cladocerans, and 5 taxa from copepods-were identified in Lake İznik. Brachionus calyciflorus, B. angularis, Notholca squamula, N. acuminata, Euchlanis dilatata, E. deflexa, Platyias quadricornis, Trichocerca similis, T. cylindrica, T. chattoni, T. lophoessa, T. bicristata, Asplanchna girodi, Conochiulus dossuarius, Synchaeta pectinata, Lecane luna, L. bulla, L. stenroosi, L. clostrocerca, L. lunaris, Lepadella patella, Dicranophorus forcipatus, Mytilina mucronata, Lophocharis salpina, Trichotria tetractis, T. pocillum, Testudinella patina, Hexarthra fennica, and Collotheca sp. from the rotifera species; …

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Contribution To The Knowledge Of The Vespidae (Hymenoptera, Aculeata) Of Turkey, With A Checklist Of The Turkish Species, Erol Yildirim, Josef Gusenleitner Jan 2012

Contribution To The Knowledge Of The Vespidae (Hymenoptera, Aculeata) Of Turkey, With A Checklist Of The Turkish Species, Erol Yildirim, Josef Gusenleitner

Turkish Journal of Zoology

This study is based upon material of the family Vespidae collected at a series of localities in Turkey between 1964 and 2010 and a review of the previous studies on the Vespidae of Turkey. Stenodynerus trotzinai (Morawitz, 1895) and Antepipona dentella Gusenleitner, 1991 are new records for the Turkish fauna. With these 2 additions and the data from previous studies, a total of 298 species and subspecies from 53 genera belonging to 4 subfamilies, Vespinae, Polistinae, Eumeninae, and Masarinae, of the family Vespidae have now been recorded from Turkey. Among them, the type localities of 3 genera, 71 species, and …

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New Records Of Water Mite (Acari: Hydrachnidia) Species For The Turkish Fauna, Yunus Esen, Vladi̇mi̇r Pesi̇c, Ci̇han Çi̇ti̇l, Orhan Erman Jan 2012

New Records Of Water Mite (Acari: Hydrachnidia) Species For The Turkish Fauna, Yunus Esen, Vladi̇mi̇r Pesi̇c, Ci̇han Çi̇ti̇l, Orhan Erman

Turkish Journal of Zoology

Four species of water mites (Acari: Hydrachnidia) are presented for the fauna of Turkey. Oxus (s. str.)angustipositus Viets, 1908; O. (s. str.) hastatus (Lundblad, 1954); Frontipodopsis (s. str.) reticulatifrons Szalay, 1945; and Hungarohydracarus subterraneus Szalay, 1943 are new records for the Turkish fauna. The description of the male O. (s. str.) hastatus, a species known for a single female specimen from Portugal, is given for the first time. Frontipodopsidae and Hungarohydracaridae are reported for the first time for Turkey.

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On The Life History Of Spirlin Alburnoides Bipunctatus (Bloch, 1782) In The Qanat Of Uzineh, Northern Iran, Rahman Patimar, Mohsen Zare, Mehdi Hesam Jan 2012

On The Life History Of Spirlin Alburnoides Bipunctatus (Bloch, 1782) In The Qanat Of Uzineh, Northern Iran, Rahman Patimar, Mohsen Zare, Mehdi Hesam

Turkish Journal of Zoology

Within the wide distribution of spirlin in Iran, populations of this species inhabit a great variety of habitats, including qanats. We hypothesized that qanats may contribute to habitat-specific variation in the life history of the fish. To test this, a total of 240 specimens of Alburnoides bipunctatus, caught in the qanat of Uzineh (northern Iran) from October 2007 to August 2008, were examined for life history attributes. The population had a 5-year life cycle. The weight-length relationship (WLR) was estimated as W = 0.0068TL^{3.2559} for males, W = 0.0079TL^{3.2067} for females, and W = 0.0072TL^{3.2387} for the population, having a …

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A Survey On Infection Of Turcinoemacheilus Kosswigi, First Record Of The Genus Procamallanus (Nematoda: Camallanidae) From Iran, Fatemeh Tajbakhsh, Kiavash Golzarianpour, Asghar Abdoli Jan 2012

A Survey On Infection Of Turcinoemacheilus Kosswigi, First Record Of The Genus Procamallanus (Nematoda: Camallanidae) From Iran, Fatemeh Tajbakhsh, Kiavash Golzarianpour, Asghar Abdoli

Turkish Journal of Zoology

The present study was conducted to identify the parasitic infection of the nemacheilid loach, Turcinoemacheilus kosswigi, in 5 rivers of the Tigris basin in Iran, from July 2007 to August 2008. Extracted from 43 fish specimens were 3 parasitic species: metacercaria of Posthodiplostomum cuticola (Digenea: Diplostomatidae) in the skin, fins, gills, and muscles; Allocreadium sp. (Digenea: Allocreadidae) and Procamallanus sp. (Nematoda: Camallanidae) in the intestine. Prevalence and mean intensity of parasitic infection were: 100%, 33 for the river Khoramroud; 12.5%, 1 for the river Hana; 50%, 1 for the river Kakareza; and 16.6%, 1 for the river Shalamzar. Specimens of …

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Age Composition And Distribution Of Red Drum (Sciaenops Ocellatus) In Offshore Waters Of The North Central Gulf Of Mexico: An Evaluation Of A Stock Under A Federal Harvest Moratorium, Sean P. Powers, Crystal Hightower, J. Marcus Drymon, Matthew W. Johnson Jan 2012

Age Composition And Distribution Of Red Drum (Sciaenops Ocellatus) In Offshore Waters Of The North Central Gulf Of Mexico: An Evaluation Of A Stock Under A Federal Harvest Moratorium, Sean P. Powers, Crystal Hightower, J. Marcus Drymon, Matthew W. Johnson

University Faculty and Staff Publications

Because of a lack of fishery- dependent data, assessment of the recovery of fish stocks that undergo the most aggressive form of management, namely harvest moratoriums, remains a challenge. Large schools of red drum (Sclaenops ocellatus) were common along the northern Gulf of Mexico until the late 1980s when increased fishing effort quickly depleted the stock. After 24 years of harvest moratorium on red drum in federal waters, the stock is in need of reassessment; however, fishery dependent data are not available in federal waters and fishery-independent data are limited. We document the distribution, age composition, growth, and condition of …

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Development Of High-Yielding Sweetgum Plantation Systems For Bioenergy Production In The Southeastern United States, Donald J. Kaczmarek, Brian C. Wachelka, Jeff Wright, Victor C. Steel, Doug P. Aubrey, David R. Coyle, Mark D. Coleman Jan 2012

Development Of High-Yielding Sweetgum Plantation Systems For Bioenergy Production In The Southeastern United States, Donald J. Kaczmarek, Brian C. Wachelka, Jeff Wright, Victor C. Steel, Doug P. Aubrey, David R. Coyle, Mark D. Coleman

Biology: Faculty Presentations

No abstract provided.

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Application Timing On Foliar Fungicide Efficacy On Sorghum In Nebraska, 2009, C. M. Schleicher, T. A. Jackson Jan 2012

Application Timing On Foliar Fungicide Efficacy On Sorghum In Nebraska, 2009, C. M. Schleicher, T. A. Jackson

Department of Plant Pathology: Faculty Publications

A foliar fungicide efficacy trial was established at the University of Nebraska-Lincoln South Central Agricultural Laboratory near Clay Center, NE. Grain sorghum hybrid NC+ 7R83 was planted on 18 May in 30-in. rows with a target population of 90,000 plants/A. The trial area was disked with a crop history of five years of continuous corn. Eight treatments and a non-treated control were replicated six times in a randomized complete block design. Each plot was four rows (10 ft) wide by 40 ft in length. . . . There were no significant differences in stay green. Stay green percentages ranged from …

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Modeling Broad-Scale Patterns Of Avian Species Richness Across The Midwestern United States With Measures Of Satellite Image Texture, Patrick D. Culbert, Volker C. Radeloff, Véronique St-Louis, Curtis H. Flather, Chadwick D. Rittenhouse, Thomas P. Albright, Anna M. Pidgeon Jan 2012

Modeling Broad-Scale Patterns Of Avian Species Richness Across The Midwestern United States With Measures Of Satellite Image Texture, Patrick D. Culbert, Volker C. Radeloff, Véronique St-Louis, Curtis H. Flather, Chadwick D. Rittenhouse, Thomas P. Albright, Anna M. Pidgeon

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Avian biodiversity is threatened, and in order to prioritize limited conservation resources and conduct effective conservation planning a better understanding of avian species richness patterns is needed. The use of image texture measures, as a proxy for the spatial structure of land cover and vegetation, has proven useful in explaining patterns of avian abundance and species richness. However, prior studies that modeled habitat with texture measures were conducted over small geographical extents and typically focused on a single habitat type. Our goal was to evaluate the performance of texture measures over broad spatial extents and across multiple habitat types with …

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Mountain Pine Beetle Attack Alters The Chemistry And Flammability Of Lodgepole Pine Foliage, Wesley G. Page, Michael J. Jenkins, Justin B. Runyon Jan 2012

Mountain Pine Beetle Attack Alters The Chemistry And Flammability Of Lodgepole Pine Foliage, Wesley G. Page, Michael J. Jenkins, Justin B. Runyon

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

During periods with epidemic mountain pine beetle (Dendroctonus ponderosae Hopkins) populations in lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) forests, large amounts of tree foliage are thought to undergo changes in moisture content and chemistry brought about by tree decline and death. However, many of the presumed changes have yet to be quantified. In this study, we quantified and compared fuel moisture, chemistry, and resulting flammability of bark beetle affected foliage in terms of ignitability, combustibility, consumability, and sustainability at a site in far eastern Idaho, USA. Results revealed substantial decreases in moisture content, the …

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Marine Vertebrates From The Hartland Shale (Upper Cretaceous: Upper Cenomanian) In Southeastern Colorado, Usa, Matthew Nagrodski, Kenshu Shimada, Bruce A. Schumacher Jan 2012

Marine Vertebrates From The Hartland Shale (Upper Cretaceous: Upper Cenomanian) In Southeastern Colorado, Usa, Matthew Nagrodski, Kenshu Shimada, Bruce A. Schumacher

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

The Hartland Shale Member of the Greenhorn Limestone was deposited in the middle of the Late Cretaceous Western Interior Seaway of North America. Rock samples rich in micro-vertebrate fossils were collected from the lower part of the Hartland Shale (ca. 94.6 Ma: early Late Cenomanian) in southeastern Colorado, USA. Through acid treatment of the rock samples, 25 marine vertebrate taxa are identified including chondrichthyans, osteichthyans, and a reptile. Chondrichthyans are represented by seven species: Ptychodus anonymus, Squalicorax curvatus, Carcharias saskatchewanensis, Archaeolamna kopingensis, Cretoxyrhina mantelli, Cretomanta canadensis, and Rhinobatos incertus. Osteichthyan fishes consist of 17 taxa: Micropycnodon kansasensis, cf. Palaeobalistum …

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Lineage-Specific Differences Between Human And Simian Immunodeficiency Virus Regulation Of Gp120 Trimer Association And Cd4 Binding, Andrés Finzi, Beatriz Pacheco, Shi-Hua Xiang, Marie Pancera, Alon Herschhorn, Liping Wang, Xing Zeng, Anik Desormeaux, Peter D. Kwong, Joseph Sodroski Jan 2012

Lineage-Specific Differences Between Human And Simian Immunodeficiency Virus Regulation Of Gp120 Trimer Association And Cd4 Binding, Andrés Finzi, Beatriz Pacheco, Shi-Hua Xiang, Marie Pancera, Alon Herschhorn, Liping Wang, Xing Zeng, Anik Desormeaux, Peter D. Kwong, Joseph Sodroski

Nebraska Center for Virology: Faculty Publications

Metastable conformations of the gp120 and gp41 envelope glycoproteins of human immunodeficiency virus type 1 (HIV-1) and simian immunodeficiency virus (SIV) must be maintained in the unliganded state of the envelope glycoprotein trimer. Binding of gp120 to the primary receptor, CD4, triggers the transition to an open conformation of the trimer, promoting interaction with the CCR5 chemokine receptor and ultimately leading to gp41-mediated virus-cell membrane fusion and entry. Topological layers in the gp120 inner domain contribute to gp120-trimer association in the unliganded state and to CD4 binding. Here we describe similarities and differences between HIV-1 and SIVmac gp120. In both …

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Subunit Organization Of The Membrane-Bound Hiv-1 Envelope Glycoprotein Trimer, Youdong Mao, Liping Wang, Christopher Gu, Alon Herschhorn, Shi-Hua Xiang, Hillel Haim, Xinzhen Yang, Joseph Sodroski Jan 2012

Subunit Organization Of The Membrane-Bound Hiv-1 Envelope Glycoprotein Trimer, Youdong Mao, Liping Wang, Christopher Gu, Alon Herschhorn, Shi-Hua Xiang, Hillel Haim, Xinzhen Yang, Joseph Sodroski

Nebraska Center for Virology: Faculty Publications

The trimeric human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein (Env) spike is a molecular machine that mediates virus entry into host cells and is the sole target for virus-neutralizing antibodies. The mature Env spike results from cleavage of a trimeric gp160 precursor into three gp120 and three gp41 subunits. Here we describe an ~11-Å cryo-EM structure of the trimeric HIV-1 Env precursor in its unliganded state. The three gp120 and three gp41 subunits form a cage-like structure with an interior void surrounding the trimer axis. Interprotomer contacts are limited to the gp41 transmembrane region, the torus-like gp41 ectodomain, and …

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A Detrimental Soil Disturbance Prediction Model For Ground-Based Timber Harvesting, Derrick A. Reeves, Matthew C. Reeves, Ann M. Abbott, Deborah S. Page-Dumroese, Mark D. Coleman Jan 2012

A Detrimental Soil Disturbance Prediction Model For Ground-Based Timber Harvesting, Derrick A. Reeves, Matthew C. Reeves, Ann M. Abbott, Deborah S. Page-Dumroese, Mark D. Coleman

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Soil properties and forest productivity can be affected during ground-based harvest operations and site preparation. The degree of impact varies widely depending on topographic features and soil properties. Forest managers who understand site-specific limits to ground-based harvesting can alter harvest method or season to limit soil disturbance. To determine the potential areal extent of detrimental (potentially plant growth limiting) soil disturbance based on site characteristics and season of harvest, we developed a predictive model based on soil monitoring data collected from 167 groundbased harvest units. Data collected included dominant site parameters (e.g., slope, aspect, soil texture, and landtype), harvest season, …

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Fish And Other Aquatic Resource Trends In The United States A Technical Document Supporting The Forest Service 2010 Rpa Assessment, Andrew J. Loftus, Curtis H. Flather Jan 2012

Fish And Other Aquatic Resource Trends In The United States A Technical Document Supporting The Forest Service 2010 Rpa Assessment, Andrew J. Loftus, Curtis H. Flather

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

The Forest and Rangeland Renewable Resources Planning Act (RPA) of 1974 requires periodic assessments of the status and trends in the Nation’s renewable natural resources including fish and other aquatic species and their habitats. Data from a number of sources are used to document trends in habitat quality, populations, resource use, and patterns of imperilment among aquatic fauna. Freshwater habitat quality varied widely across the United States. Nationwide, more than half of monitored lakes were ranked in good condition, but the percentage ranged from a high of 91 percent in the upper Midwest to a low of 1 percent in …

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