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2007

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Assessment Of Fecal Bacteria Contamination In Sewage And Non-Sewage Impacted Mangrove Ecosystems Along The Coast Of Dar Es Salaam, A. A. Abbu, Thomas J. Tj Lyimo Dec 2007

Assessment Of Fecal Bacteria Contamination In Sewage And Non-Sewage Impacted Mangrove Ecosystems Along The Coast Of Dar Es Salaam, A. A. Abbu, Thomas J. Tj Lyimo

Tanzania Journal of Science

Microbiological quality of the intertidal pool water was evaluated in sewage impacted (Mtoni Kijichi) and non-sewage impacted (Rasi Dege) mangrove forest sites along the coast of Dar es Salaam, Tanzania. The Most Probable Number method was used for estimating the total coliform (TC), fecal coliform (FC) and fecal enterococci (ENT) levels. In addition, physicochemical parameters (temperature, pH, salinity and nutrients) were measured. The results for microbial fecal indicators were compared to the World Health Organisation (WHO) and United States Environmental Protection Agency (USEPA) guidelines for marine recreational and shellfish harvesting waters. Fecal bacteria contamination was significantly higher at Mtoni Kijichi …


Cerebrospinal Fluid Involvement In A Case Of Visceral Leishmaniasis Associated With Hemophagocytic Lymphohistiocytosis, Mahmoud Fathalla, Javad Hashim, Hussein Wali, Yasser Dec 2007

Cerebrospinal Fluid Involvement In A Case Of Visceral Leishmaniasis Associated With Hemophagocytic Lymphohistiocytosis, Mahmoud Fathalla, Javad Hashim, Hussein Wali, Yasser

Sultan Qaboos University Medical Journal

Hemophagocytic Lymphohistiocytosis (HLH) implies a benign generalized histiocytic proliferate with erythrophagocytosis and it includes familial hemophagocytic lymphohistiocytosis and secondary hemophgocytosis. Spinal fluid changes like mild to moderate pleocytosis (most of the cells are lymphocytes and macrophages) and sometimes hemophagocytosis are seen in primary HLH but are not reported in secondary HLH. Here we report a case of a previously healthy 10 months old male infant who was diagnosed as familial HLH with evidence of CSF hemophagocytosis. He was started on the HLH 2004 treatment protocol with no improvement. A second bone marrow aspiration revealed leshmania donovani antibodies and he was …


Seasonal Appearance And Monitoring Of Invasive Species In The Great Bay Estuarine System, Larry G. Harris, Jennifer A. Dijkstra Dec 2007

Seasonal Appearance And Monitoring Of Invasive Species In The Great Bay Estuarine System, Larry G. Harris, Jennifer A. Dijkstra

PREP Reports & Publications

The University of New Hampshire Zoology Department reports on a study designed to synthesize existing data on invasive species in the estuary and the surrounding area, compare succession between two panel studies (1979 to 1982 and 2003 to 2006), seasonally monitor invasive species in the Great Bay Estuary, and identify predators of invasive species. Researchers identified species most likely to invade the Great Bay Estuary, analyzed succession between two long-term panel studies separated by approximately 25 years, collected presence/absence and abundance data of invasive species at four sites within the Great Bay Estuarine System and identified potential predators of invasive …


Interagency Science And Research: Quarterly Progress Report, Period Ending December 31, 2007, Margaret N. Rees Dec 2007

Interagency Science And Research: Quarterly Progress Report, Period Ending December 31, 2007, Margaret N. Rees

Interagency Science and Research Strategy

  • Meetings were held with the SNAP Recreation Team and the SNAP Cultural Resources Team to request assistance in the development of the science strategy. Draft versions of interagency goals, subgoals, science questions, and associated tasks were given to each team for review and input.
  • Plans were prepared for the peer review of science proposals submitted for consideration as Conservations Initiatives in SNPLMA Round 9.
  • Proceedings of the natural resources management workshop held on September 13 were completed and sent to the Science & Research Team for review by members.
  • An important focus of the Science and Research Team was the …


Joint Fire Science Program – Lake Mead National Recreation Area: Revegetating Burned Arid Lands: Identifying Successful Native Species Using Trait And Competition Analysis, Quarterly Progress Report, October 1, 2007 To December 31, 2007, Margaret N. Rees Dec 2007

Joint Fire Science Program – Lake Mead National Recreation Area: Revegetating Burned Arid Lands: Identifying Successful Native Species Using Trait And Competition Analysis, Quarterly Progress Report, October 1, 2007 To December 31, 2007, Margaret N. Rees

Fire Science

The task agreement was awarded to UNLV on October 1, 2007. This report covers the period October 1, 2007 to December 31, 2007. The following activities have been conducted toward meeting or exceeding deliverables in the statement of work: hiring and project start and experimental set-up


Limnological Assistance For The Lake Mead National Recreation Area In Meeting The Challenge Of The Water 2025 Initiative: Quarterly Progress Report, Period Ending: December 31, 2007, Margaret N. Rees Dec 2007

Limnological Assistance For The Lake Mead National Recreation Area In Meeting The Challenge Of The Water 2025 Initiative: Quarterly Progress Report, Period Ending: December 31, 2007, Margaret N. Rees

Limnological Studies

  • The limnologist position has been announced.
  • Project 1: Review of the draft Boulder Basin Adaptive Management Plan is underway.
  • Project 2: Development of a white paper expressing the joint needs of the entities involved in Water 2025 projects is being coordinated.
  • Project 3: A bibliographic reference spreadsheet organizing literature citations related to quagga and zebra mussel research has been completed.
  • Project 4: A comprehensive literature search of Lake Mead limnology is well underway; an Access database has been designed to organize reference citations; and a special collections library at UNLV is being established to house original rare documents and other …


Lake Mead National Recreation Area Sensitive Wildlife Species Monitoring And Analysis: Quarterly Progress Report, Period Ending December 31, 2007, Margaret N. Rees Dec 2007

Lake Mead National Recreation Area Sensitive Wildlife Species Monitoring And Analysis: Quarterly Progress Report, Period Ending December 31, 2007, Margaret N. Rees

Wildlife Monitoring

Project 1. Relict Leopard Frog Monitoring, Management, and Research

  • Fall surveys completed at all natural and translocation sites.
  • Coordination for a potential translocation site on BLM lands in the Gold Butte area ongoing – the aim is that this site will be ready for translocations in 2008.
  • Coordination ongoing for evaluation of a translocation site on BLM lands in the Black Mountains, AZ – the plan is to complete compliance in 2008.
  • Coordination and assistance provided to UNLV research efforts on habitat improvements at Blue Point, Rogers, and Pupfish Refuge springs.
  • Relict Leopard Frog Conservation Team meeting held in December. …


A Novel Runx2 Missense Mutation Predicted To Disrupt Dna Binding Causes Cleidocranial Dysplasia In A Large Chinese Family With Hyperplastic Nails, Shaohua Tang, Qiyu Xu, Xueqin Xu, Jicheng Du, Xuemei Yang, Yusheng Jiang, Xiaoqin Wang, Nancy Speck, Taosheng Huang Dec 2007

A Novel Runx2 Missense Mutation Predicted To Disrupt Dna Binding Causes Cleidocranial Dysplasia In A Large Chinese Family With Hyperplastic Nails, Shaohua Tang, Qiyu Xu, Xueqin Xu, Jicheng Du, Xuemei Yang, Yusheng Jiang, Xiaoqin Wang, Nancy Speck, Taosheng Huang

Dartmouth Scholarship

Background: Cleidocranial dysplasia (CCD) is a dominantly inherited disease characterized by hypoplastic or absent clavicles, large fontanels, dental dysplasia, and delayed skeletal development. The purpose of this study is to investigate the genetic basis of Chinese family with CCD.

Methods: Here, a large Chinese family with CCD and hyperplastic nails was recruited. The clinical features displayed a significant intrafamilial variation. We sequenced the coding region of the RUNX2 gene for the mutation and phenotype analysis.

Results: The family carries a c.T407C (p.L136P) mutation in the DNA- and CBFβ-binding Runt domain of RUNX2. Based on the crystal structure, we predict this …


Mice Deficient In Involucrin, Envoplakin, And Periplakin Have A Defective Epidermal Barrier., Lisa M Sevilla, Rachida Nachat, Karen R Groot, John F Klement, Jouni Uitto, Philippe Djian, Arto Määttä, Fiona M Watt Dec 2007

Mice Deficient In Involucrin, Envoplakin, And Periplakin Have A Defective Epidermal Barrier., Lisa M Sevilla, Rachida Nachat, Karen R Groot, John F Klement, Jouni Uitto, Philippe Djian, Arto Määttä, Fiona M Watt

Department of Dermatology and Cutaneous Biology Faculty Papers

The cornified envelope is assembled from transglutaminase cross-linked proteins and lipids in the outermost epidermal layers and is essential for skin barrier function. Involucrin, envoplakin, and periplakin form the protein scaffold on which the envelope assembles. To examine their combined function, we generated mice deficient in all three genes. The triple knockouts have delayed embryonic barrier formation and postnatal hyperkeratosis (abnormal accumulation of cornified cells) resulting from impaired desquamation. Cornified envelopes form but are ultrastructurally abnormal, with reduced lipid content and decreased mechanical integrity. Expression of proteases is reduced and the protease inhibitor, serpina1b, is highly upregulated, resulting in defective …


Chemical Constituents And Biological Activity Of Three Tanzanian Wild Mushroom Species, L.D. Baraza, C. C. Joseph, M. J. Moshi, M. H. H. Nkunya Dec 2007

Chemical Constituents And Biological Activity Of Three Tanzanian Wild Mushroom Species, L.D. Baraza, C. C. Joseph, M. J. Moshi, M. H. H. Nkunya

Tanzania Journal of Science

The three Tanzanian wild mushroom species Termitomyces letestui, Lactarius edulis and Agaricus sp. aff. arvensis yielded ergosterol, 5,8-peroxyergosterol and ergosta-5,22-dien-3β-ol, and a mixture of ergosterol, ergosta-7,22-dien-3β-ol and ergosta-7-en-3β-ol whose composition was deduced from gas chromatography/mass spectroscopic (GC/MS) analysis of the trimethysilylated mixture. GC/MS analysis of the lipid fraction from T. letestu revealed the presence of linoleic (C18:2), stearic (C18:0), oleic (C18:1), palmitic (C16:0), pentadecanoic (C15:0) and myristic (C14:0) acid. Polar T. letestui and L. edulis fractions yielded α,α,1'trehalose andmannitol. Some of the crude extracts from the three mushroom species showed mild antimicrobial, mosquito larvicidal and cytotoxic activities. The chemical composition …


An Assessment Of Methods For Sampling Carabid Beetles (Coleptera: Carabidae) In A Montane Rain Forest, B. A. Nyundo, J. G. Yarro Dec 2007

An Assessment Of Methods For Sampling Carabid Beetles (Coleptera: Carabidae) In A Montane Rain Forest, B. A. Nyundo, J. G. Yarro

Tanzania Journal of Science

Pitfall trapping is the traditional method for sampling carabid beetles and other grounddwelling invertebrates. Tests were carried out in the Udzungwa Mountains National Park between March 1999 and July 2000. Results indicated that pitfall traps were less efficient compared to manual searching methods, both in terms of relative abundance and species richness of carabid beetles. The results are discussed in the context of biodiversity inventories in theEastern Arc Mountains.


Effect Of High Pressurized Carbon Dioxide On Escherichia Coli, I. P. Bateebe, O Kibazohi Dec 2007

Effect Of High Pressurized Carbon Dioxide On Escherichia Coli, I. P. Bateebe, O Kibazohi

Tanzania Journal of Science

Carbon dioxide at high pressure can retard microbial growth and sometimes kill microorganisms depending on values of applied pressure, temperature and exposure time. In this study the effect of high pressurised carbon dioxide (HPCD) on Escherichia coli was investigated. Culture of E. coli was subjected to high pressurised carbon dioxide at 15, 25 and 35 bar, and varying exposure times of 20, 40, 60 and 90 minutes at room temperature (27 oC). Microbial inactivation increased with pressure and exposure time. For the first 20 minutes reduction of viable microbial cells was 18%, 30% and 36% at 15, 25 and 35 …


Preparation And Nucleophilic Substitution Of The 2,4,6-Triphenylpyridinium Salts, Diazonium Intermediates And N,N-1,2-Benzenedisulfonylimides Of Chiral Amino Acids, S. A. Said Dec 2007

Preparation And Nucleophilic Substitution Of The 2,4,6-Triphenylpyridinium Salts, Diazonium Intermediates And N,N-1,2-Benzenedisulfonylimides Of Chiral Amino Acids, S. A. Said

Tanzania Journal of Science

Three methods for preparation of D-amino acids by nucleophilic substitution on derivatives of their L-antipodes have been attempted. Nucleophilic substitution on optically active phenylalanine ethyl ester triphenylpyridinium salt yielded partial inverted azide products. The N,N-disulfonylimide intermediate of the same ester was synthesized in high yield and optical purity, but the substitution reaction on this compound was not achieved. Diazotization of amino acid ammonium chlorides and tosylates in solution of sodium azide in aprotic solvents gave optically active chloro and tosyl compounds instead of the intended azide products. Alternative methods to circumvent the problem of the competing ammonium salt counterions duringdiazotization …


Impact Of Small Scale Gold Mining On Soils Of The Wetland Forests In East Usambara, Tanzania, C. Kweyunga, R. B. M. Rbm Senzota Dec 2007

Impact Of Small Scale Gold Mining On Soils Of The Wetland Forests In East Usambara, Tanzania, C. Kweyunga, R. B. M. Rbm Senzota

Tanzania Journal of Science

Soil pits in disturbed and natural wetland forests of East Usambara were excavated and soil profile samples collected and analysed for physical and chemical properties. Their physical and chemical characteristics were found to be sharply different from those of the surrounding hills. Differences included lack of A Horizon, water saturation, presence of very high organic matter, very low pH and hence very poor in basic cations, and low microbial activity. Nutrient recycling, especially nitrogen and phosphorus, tended to shift from mineralization to immobilization. Effects of soil disturbance on both physical and chemical characteristics of the soils were also very vivid. …


Jawetz, Melnick & Adelberg’S Medical Microbiology 24th Edition, Muhannad F. Al-Kobaisi Dec 2007

Jawetz, Melnick & Adelberg’S Medical Microbiology 24th Edition, Muhannad F. Al-Kobaisi

Sultan Qaboos University Medical Journal

No abstract provided.


Evolutionary Medicine Of Kani Tribal’S Botanical Knowledge In Agasthiayamalai Biosphere Reserve, South India, John De Britto, R. Mahesh Dec 2007

Evolutionary Medicine Of Kani Tribal’S Botanical Knowledge In Agasthiayamalai Biosphere Reserve, South India, John De Britto, R. Mahesh

Ethnobotanical Leaflets

Agasthiayamalai Biosphere Reserve in Tirunelveli zones have had five Kani tribal settlement surveys of ethnomedicinal utilization with more than 480 species of which only 70 species are been reported during the field study 2006-2007. Collected ancestral knowledge was documented in database format by the software Visual Basic 6.0 and M.S Access. Kani tribes reveal that they are capable of treating various diseases. Exploitation and documentation of traditional medicine is essential for the future. Such study will be useful to understand the role and importance of the tribal botanical knowledge in the conservation of medicinal plants of this area.


Regional Body Composition In College-Aged Caucasians From Anthropometric Measures, Robert T. Davidson, Cameron B. Ritchie Dec 2007

Regional Body Composition In College-Aged Caucasians From Anthropometric Measures, Robert T. Davidson, Cameron B. Ritchie

Faculty Publications

Quantitating fat and lean tissue in isolated body regions may be helpful or required in obesity and health-outcomes research. However, current methods of regional body composition measurement require specialized, expensive equipment such as that used in computed tomography or dual energy x-ray absorptiometry (DEXA). Simple body size or circumference measurement relationships to body composition have been developed but are limited to whole-body applications. We investigated relationships between body size measurements and regional body composition. Methods Using DEXA technology we determined the fat and lean tissue composition for six regions of the body in predominantly Caucasian, college-aged men (n = 32) …


An Optical Model For Heat And Salt Budget Estimation For Shallow Seas, Hari Warrior, Kendall L. Carder Dec 2007

An Optical Model For Heat And Salt Budget Estimation For Shallow Seas, Hari Warrior, Kendall L. Carder

Marine Science Faculty Publications

The effects of the underwater light field on heat-budget calculations for shallow waters are developed and applied for the region of Bahamas. Most of the general circulation models use a simplified heat budget scheme based on Jerlov water types, and do not account for optical bottom effects. by optical bottom effect, we mean the bottom absorption and reflection of the short-wave radiation, which in turn affects the thermal stratification and heat exchange with the atmosphere. In this paper, this optical bottom effect is added to a 3D turbulence model (a 1D model called GOTM is coupled to a 3D model …


Growth And Demography Of One Population Of The Lizard Sceloporus Mucronatus Mucronatus, Angela M. Ortega-León, Emily R. Smith, J. Jaime Zúñiga-Vega, Fausto R. Méndez–De La Cruz Dec 2007

Growth And Demography Of One Population Of The Lizard Sceloporus Mucronatus Mucronatus, Angela M. Ortega-León, Emily R. Smith, J. Jaime Zúñiga-Vega, Fausto R. Méndez–De La Cruz

Western North American Naturalist

We report on growth and demography of Sceloporus mucronatus mucronatus, a lizard subspecies endemic to central Mexico. We characterize the life history of this subspecies, provide quantitative information relevant to conservation, and add to the growing literature on the diversity of life histories in the genus Sceloporus. We calculated body growth rates and fitted them to the Von Bertalanffy, the logistic-by-length, and the logistic-by-weight growth models. The Von Bertalanffy model provided the best fit, and we used it to analyze the growth pattern. Growth rates were similar during the 1st year of life in both sexes, but after …


Diatom Species Composition And Ecology Of The Animas River Watershed, Colorado, Usa, Gerald V. Sgro, John B. Poole, Jeffery R. Johansen Dec 2007

Diatom Species Composition And Ecology Of The Animas River Watershed, Colorado, Usa, Gerald V. Sgro, John B. Poole, Jeffery R. Johansen

Western North American Naturalist

The diatom flora of selected sites in the Animas River Watershed, San Juan County, Colorado, was studied. Eighty diatom taxa were identified from 10 sites: 8 sites on the Animas River and 1 site each on the Cement and Cascade tributaries. The sample diatom abundance was dominated by Achnanthidium minutissimum, Encyonema silesiacum, Aulacoseira distans, Hannaea arcus, and Diatoma mesodon. The presence of teratologic specimens of Fragilaria and Achnanthidium in the samples indicated the possibility of metals contamination. Diatom diversity was low and Lange-Bertalot pollution index scores indicated little organic pollution evidenced from diatom composition. There …


Moistened Seeds Increase Rodent Trap Success, John C. Tull, Michael W. Sears Dec 2007

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

Western North American Naturalist

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 …


New Distribution Records For The Querétero Dusky Rattlesnake Crotalus Aquilus (Viperidae), With Comments On Morphology And Habitat Use, Jesse M. Meik, Estrella Mociño Deloya, Kirk Setser Dec 2007

New Distribution Records For The Querétero Dusky Rattlesnake Crotalus Aquilus (Viperidae), With Comments On Morphology And Habitat Use, Jesse M. Meik, Estrella Mociño Deloya, Kirk Setser

Western North American Naturalist

We provide the 1st documented accounts of the Mexican endemic rattlesnake Crotalus aquilus from the state of México. The new records extend the known distribution of the species into a region where it may be sympatric with the superficially similar C. triseriatus. Because these taxa have previously been subject to some taxonomic confusion, we performed a preliminary morphological comparison using individuals of both species obtained from proximal localities. Our analyses support the supposition that these taxa are morphologically distinct. The new localities for C. aquilus are situated in high valleys that have been extensively modified by human settlement and …


Long-Term Vegetation Dynamics In A Cut Western Juniper Woodland, Jonathan D. Bates, Richard F. Miller, Tony Svejcar Dec 2007

Long-Term Vegetation Dynamics In A Cut Western Juniper Woodland, Jonathan D. Bates, Richard F. Miller, Tony Svejcar

Western North American Naturalist

Western juniper (Juniperus occidentalis spp. occidentalis Hook.) expansion in the northern Great Basin has reduced shrubsteppe productivity and diversity. Chainsaw cutting of western juniper woodlands is commonly applied to remove tree interference and restore sagebrush plant communities. Studies assessing understory response following cutting have been limited to early successional stages and have not evaluated the effects of western juniper debris on plant succession. Cutting western juniper produces a large amount of debris which is commonly left on site, occupying a significant portion of treated areas. This study evaluated successional dynamics spanning 13 years after western juniper cutting. Four 0.45-ha …


Discovery Of A Large Population Of The Rare Winter Stonefly Isocapnia Mogila Ricker In The Mad River, California (Plecoptera, Capniidae), Richard W. Baumann, Jonathan J. Lee Dec 2007

Discovery Of A Large Population Of The Rare Winter Stonefly Isocapnia Mogila Ricker In The Mad River, California (Plecoptera, Capniidae), Richard W. Baumann, Jonathan J. Lee

Western North American Naturalist

Isocapnia mogila, a rare winter stonefly, is found in good numbers in Humboldt County, California. In the 50 years since this species was described, very few specimens were recorded from only 4 sites in California and Oregon. Emergence seems to be higher in the fall and early winter than in the late winter and spring.


Large Mixed-Species Dispersal Flights For Predatory And Scavenging Aquatic Heteroptera And Coleoptera, Northern Arizona, Usa, Lawrence E. Stevens, John T. Polhemus, Richard S. Durfee, Carl A. Olson Dec 2007

Large Mixed-Species Dispersal Flights For Predatory And Scavenging Aquatic Heteroptera And Coleoptera, Northern Arizona, Usa, Lawrence E. Stevens, John T. Polhemus, Richard S. Durfee, Carl A. Olson

Western North American Naturalist

We report 4 incidents of large (hundreds to hundreds of thousands of individuals) mixed-species flights of predatory and scavenging aquatic Heteroptera and Coleoptera. The events occurred on normal (mostly clear, calm) autumn 2005 and spring 2006 late afternoons near Flagstaff, Arizona. Flight days were either near the full moon or in advanced waning lunar periods. At least 18 species were involved in the flights, with as many as 16 species (7 species of Heteroptera in 3 families, 9 species of Coleoptera in 2 families) in a single flight. Heteroptera (especially from the family Corixidae) were 2–4 orders of magnitude more …


Home Range Size Of Black-Backed Woodpeckers In Burned Forests Of Southwestern Idaho, Jonathan G. Dudley, Victoria A. Saab Dec 2007

Home Range Size Of Black-Backed Woodpeckers In Burned Forests Of Southwestern Idaho, Jonathan G. Dudley, Victoria A. Saab

Western North American Naturalist

We examined home range size of Black-backed Woodpeckers (Picoides arcticus) in burned ponderosa pine (Pinus ponderosa) / Douglas-fir (Pseudotsuga menziesii) forests of southwestern Idaho during 2000 and 2002 (6 and 8 years following fire). Home range size for 4 adult males during the post-fledging period was 115.6–420.9 ha using the 95% fixed-kernel method, and 150.4–766.1 ha using the 100% minimum convex polygon method. Smoothed bootstrap estimates (95%) were 130.0–521.9 ha. Home range sizes were significantly smaller 6 years after fire than 8 years after fire. Each male had from 2 to 8 areas of …


Observations On An Association Between The Weevil Scaphomorphus Trivittatus (Say) And Two Astragalus Species On Selenium-Rich Soils In Carbon County, Utah, Gary R. Hooper, Boyd F. Holdaway Dec 2007

Observations On An Association Between The Weevil Scaphomorphus Trivittatus (Say) And Two Astragalus Species On Selenium-Rich Soils In Carbon County, Utah, Gary R. Hooper, Boyd F. Holdaway

Western North American Naturalist

The weevil Scaphomorphus trivittatus (Say) was found in close association with Astragalus praelongus var. elliseae (Rydb.) and Astragalus asclepiadoides (Jones) in selenium-containing soils in Carbon County, Utah. The weevils fed on roots of the Astragalus species and formed soil cocoons, which were attached to the tap roots. The weevils pupated and developed into adults in these cocoons over the fall and winter and then emerged in the spring. The plants and soil cocoons contained highly elevated levels of selenium compared to the soils. The weevils, in contrast, differed little from the soils in selenium content.


Variation In Ant Populations With Elevation, Tree Cover, And Fire In A Pinyon-Juniper–Dominated Watershed, Eugénie M. Montblanc, Jeanne C. Chambers, Peter F. Brussard Dec 2007

Variation In Ant Populations With Elevation, Tree Cover, And Fire In A Pinyon-Juniper–Dominated Watershed, Eugénie M. Montblanc, Jeanne C. Chambers, Peter F. Brussard

Western North American Naturalist

Climate change and fire suppression have facilitated expansion of pinyon-juniper woodlands into sagebrush-steppe ecosystems of the Great Basin, USA, resulting in a loss of biological diversity. To assess the effects of using prescribed fire in restoration efforts, ant abundance, species richness, and composition were examined pre- and post-burn along the elevation and tree cover gradients encompassed by a pinyon-juniper woodland in a central Nevada watershed. Ants were sampled using pitfall traps in 6 sites for the elevation study and in 2 sites for the tree cover study, representing paired burn and control sites in a randomized block design. Vegetation and …


The Scotopic Visual Sensitivity Of Four Species Of Trout: A Comparative Study, Russell B. Rader, Timberley Belish, Michael K. Young, John Rothlisberger Dec 2007

The Scotopic Visual Sensitivity Of Four Species Of Trout: A Comparative Study, Russell B. Rader, Timberley Belish, Michael K. Young, John Rothlisberger

Western North American Naturalist

We compared the maximum scotopic visual sensitivity of 4 species of trout from twilight (mesotopic) to fully dark-adapted vision. Scotopic vision is the minimum number of photons to which a fully dark-adapted animal will show a behavioral response. A comparison of visual sensitivity under controlled laboratory conditions showed that brown trout (Salmo trutta) and brook trout (Salvelinus fontinalis) had maximum scotopic thresholds (1.1 × 10−4 µmol · m−2s−1, ~0.005 lux) 2 times lower than rainbow trout (Oncorhyncus mykiss) and Snake River cutthroat trout (Oncorhynchus clarki bouvieri), which …


Modeling Aboveground Biomass Of Tamarix Ramosissima In The Arkansas River Basin Of Southeastern Colorado, Usa, Paul Evangelista, Sunil Kumar, Thomas J. Stohlgren, Alycia W. Crall, Gregory J. Newman Dec 2007

Modeling Aboveground Biomass Of Tamarix Ramosissima In The Arkansas River Basin Of Southeastern Colorado, Usa, Paul Evangelista, Sunil Kumar, Thomas J. Stohlgren, Alycia W. Crall, Gregory J. Newman

Western North American Naturalist

Predictive models of aboveground biomass of nonnative Tamarix ramosissima of various sizes were developed using destructive sampling techniques on 50 individuals and four 100- m2 plots. Each sample was measured for average height (m) of stems and canopy area (m2) prior to cutting, drying, and weighing. Five competing regression models (P < 0.05) were developed to estimate aboveground biomass of T. ramosissima using average height and/or canopy area measurements and were evaluated using Akaike's Information Criterion corrected for small sample size (AICc). Our best model (AICc = −148.69, ΔAICc = 0) successfully predicted T. ramosissima aboveground biomass (R2 = 0.97) …