Giongo A.,University of Florida |
Favet J.,University of Geneva |
Lapanje A.,Institute of Physical Biology |
Gano K.A.,University of Florida |
And 17 more authors.
Aerobiologia | Year: 2013
Microbiological studies on the intercontinental transport of dust are confounded by the difficulty of obtaining sufficient material for analysis. Axenic samples of dust collected at high altitudes or historic specimens in museums are often so small and precious that the material can only be sacrificed when positive results are assured. With this in mind, we evaluated current methods and developed new ones in an attempt to catalogue all microbes present in small dust or sand samples. The methods used included classical microbiological approaches in which sand extracts were plated out on a variety of different media, polymerase chain reaction (PCR)-based amplification of 16S/18S rRNA sequences followed by construction of clone libraries, PCR amplification of 16S rRNA sequences followed by high-throughput sequencing (HtS) of the products and direct HtS of DNA extracted from the sand. A representative sand sample collected at Bahaï Wadi in the desert of the Republic of Chad was used. HtS with or without amplification showed the most promise and can be performed on ≤100 ng DNA. Since living microbes are often required, current best practices would involve geochemical and microscopic characterisation of the sample, followed by DNA isolation and direct HtS. Once the microbial content of the sample has been deciphered, growth conditions (including media) can be tailored to isolate the micro-organisms of interest. © 2012 Springer Science+Business Media B.V.
Albrecht B.A.,BIO WEST Inc. |
Holden P.B.,BIO WEST Inc. |
Kegerries R.B.,BIO WEST Inc. |
Golden M.E.,U.S. Department of Agriculture
Lake and Reservoir Management | Year: 2010
Populations of the endangered razorback sucker (Xyrauchen texanus) have been reduced in the Colorado River during much of the last century. The inability of razorback sucker to recruit in the presence of nonnative fishes and altered flow regimes is thought to be the major factor contributing to their decline. Through funding from the Southern Nevada Water Authority and the US Bureau of Reclamation, we have conducted an ongoing razorback sucker research project on Lake Mead, Arizona and Nevada, since 1996. A major emphasis of this research has been to determine if natural recruitment was occurring in Lake Mead and identify reasons for that recruitment. Ages calculated using a nonlethal aging technique for 186 individual razorback sucker indicate the Lake Mead population is relatively young and that natural, wild recruitment has regularly occurred since the late 1970s. Comparisons of back-calculated ages of captured fish with historical Lake Mead water elevations provide evidence that a change in annual lake level fluctuations is the most likely mechanism that initiated this recruitment phenomenon. Lake level changes along with inundated terrestrial vegetation and turbidity in specific sites in Lake Mead may provide littoral nursery cover for larval and juvenile razorback sucker, allowing them to avoid predation. © 2010 Copyright Taylor and Francis Group, LLC.
Texas environmental flow standards and the hydrology-based environmental flow regime methodology [Normes des débits environnementaux au Texas et méthodologie du régime de débit environnemental à base hydrologique]
Opdyke D.R.,Anchor QEA LLC |
Oborny E.L.,BIO WEST Inc. |
Vaugh S.K.,HDR |
Mayes K.B.,Texas Parks and Wildlife Department
Hydrological Sciences Journal | Year: 2014
In 2007, the Texas legislature created a program to identify environmental flow standards statewide through the coordinated efforts of scientific and stakeholder groups and rulemaking by the Texas Commission on Environmental Quality. To aid in this task, a Hydrology-based Environmental Flow Regime (HEFR) method was developed that combines a suite of user-customizable hydrologic statistics with an implementation framework. Following the concepts of the Natural Flow Paradigm, the methodology includes the separation of a long-term hydrograph into key flow components (e.g. subsistence, base, high-flow pulse and overbank) defined by the Texas Instream Flow Program. Seasonal, annual and inter-annual flow component statistics were then coupled with biology, water quality and geomorphology overlays, where available, and with implementation rules applied to example large-scale water supply projects to support development of environmental flow standards for use in water rights permit conditions. The HEFR methodology and resulting flow recommendations are compared to two contemporary in-stream flow studies and adopted environmental flow standards. Subsistence flows were fairly similar. Baseflows were in a similar range, but fewer than three seasonal levels have sometimes been specified in in-stream flow studies. Episodic events are quite different in terms of magnitude, frequency, duration and applicable number. Editor D. Koutsoyiannis; Guest editor M. AcremanCitation Opdyke, D.R. Oborny, E.L. Vaugh, S.K. and Mayes, K.B. 2014. Texas environmental flow standards and the hydrology-based environmental flow regime methodology. Hydrological Sciences Journal, 59 (3-4), 820-830. © 2014 © 2014 IAHS Press.
Manning R.W.,107 LBJ Cove |
Heaney M.R.,BIO WEST Inc. |
Sagot M.,Texas Tech University |
Baker R.J.,Texas Tech University
Southwestern Naturalist | Year: 2014
We review the known records of desert shrews from Nevada and report the results of genetic analyses of a specimen from Ash Meadows National Wildlife Refuge, Nye County, Nevada, which help clarify the evolutionary relationships of the genus Notiosorex from southwestern United States.
Simpkins C.,BIO WEST Inc. |
Talluri K.,BIO WEST Inc. |
Williams M.,Howard University
Military Medicine | Year: 2016
Objective: The following were studied in a perimortem mouse model of rapid blood loss: (a) efficacy of a prototypical micellar colloid, Intralipid 20%, (IL20), compared to albumin (b) comparison of intra-arterial and intravenous resuscitation, (c) efficacy of IL20 at a volume 2 × the volume of blood removed, and (d) efficacy of oxygenated IL20 after clinical death (CD). Methods: CD, the absence of breathing and zero blood pressure (BP), was produced by removing 55% of the blood volume within 3 minutes. After CD, the chest was opened to observe ventricular contraction. IL20, Ringer’s lactate (RL), or albumin was infused perimortem. Results: Without resuscitation CD occurred in 2.85 ± 0.40 minutes. Ventricular contraction persisted 20.50 ± 1.11 minutes after CD. RL infused immediately after CD restored breathing if given intra-arterially but not intravenously. IL20 was superior to the prototypical colloid, albumin in maintaining the BP. Increasing the volume of IL20 further increased BP. Delayed RL infusion after CD failed to restore breathing. Delayed resuscitation after CD with oxygenated IL20 restored breathing and BP. Conclusions: Micellar colloid is superior to the prototypical colloid albumin and can possibly be of use when signs of life are no longer present. In extremis, intra-arterial infusion is superior to intravenous infusion. © Association of Military Surgeons of the U.S. All rights reserved.
Dong J.,Wilmar International |
Yan W.,National Research Council Canada |
Bock C.,National Research Council Canada |
Nokhrina K.,National Research Council Canada |
And 2 more authors.
BMC Plant Biology | Year: 2013
Background: myo-Inositol (Ins) metabolism during early stages of seed development plays an important role in determining the distributional relationships of some seed storage components such as the antinutritional factors, sucrose galactosides (also known as raffinose oligosaccharides) and phytic acid (PhA) (myo-inositol 1,2,3,4,5,6-hexakisphosphate). The former is a group of oligosaccharides, which plays a role in desiccation at seed maturation. They are not easily digested by monogastric animals, hence their flatulence-causing properties. Phytic acid is highly negatively charged, which chelates positive ions of essential minerals and decreases their bioavailability. It is also a major cause of phosphate-related water pollution. Our aim was to investigate the influence of competitive diversion of Ins as common substrate on the biosynthesis of phytate and sucrose galactosides. Results: We have studied the initial metabolic patterns of Ins in developing seeds of Brassica napus and determined that early stages of seed development are marked by rapid deployment of Ins into a variety of pathways, dominated by interconversion of polar (Ins phosphates) and non-polar (phospholipids) species. In a time course experiment at early stages of seed development, we show Ins to be a highly significant constituent of the endosperm and seed coat, but with no phytate biosynthesis occurring in either tissue. Phytate accumulation appears to be confined mainly within the embryo throughout seed development and maturation. In our approach, the gene for myo-inositol methyltransferase (IMT), isolated from Mesembryanthemum crystallinum (ice plant), was transferred to B. napus under the control of the seed-specific promoters, napin and phaseolin. Introduction of this new metabolic step during seed development prompted Ins conversion to the corresponding monomethyl ether, ononitol, and affected phytate accumulation. We were able to produce homozygous transgenic lines with 19% - 35% average phytate reduction. Additionally, changes in the raffinose content and related sugars occurred along with enhanced sucrose levels. Germination rates, viability and other seed parameters were unaffected by the IMT transgene over-expression. Conclusions: Competitive methylation of Ins during seed development reduces seed antinutritional components and enhances its nutritional characteristics while maintaining adequate phosphate reserves. Such approach should potentially raise the canola market value and likely, that of other crops. © 2013 Dong et al.; licensee BioMed Central Ltd.
Johnson M.S.,U.S. Fish and Wildlife Service |
Johnson M.S.,Texas A&M University |
Bolick A.,U.S. Fish and Wildlife Service |
Alexander M.,U.S. Fish and Wildlife Service |
And 5 more authors.
Journal of Parasitology | Year: 2012
Centrocestus formosanus (Trematoda: Heterophyidae) is an invasive fish parasite in the Comal River, Texas, and is considered a threat to the federally endangered fountain darter, Etheostoma fonticola. Monitoring densities of C. formosanus cercariae is crucial to determining levels of infection pressure. We sampled 3 sites in the Comal River during 2 sampling periods, the first during 2006-2007, and again during 2009-2010. Two of the sites were located in the upstream reach of Landa Lake, sites HS and LA, and the third site was located downstream of Landa Lake in the old channel of the river. Cercariae densities were highest at the downstream most site (EA), followed by sites LA and HS, during both sampling periods, but a significant decline in cercariae density was observed between the first and second sampling periods. Several abiotic factors were monitored, including total stream discharge, wading discharge, temperature, and dissolved oxygen, but no river-wide trends were observed. Therefore, we speculate that these factors do not adequately explain the observed long-term decline in cercariae density. We propose that the decline is simply a reflection of a typical pattern followed by most invasive species as they gradually become integrated into the local community following an initial explosive growth in population size. Although cercariae densities may be abating, fountain darters in the Comal River are still threatened by the parasite, and conservation efforts must focus on reducing levels of infection pressure from the parasite whenever possible. © American Society of Parasitologists 2012.
Perkin J.S.,Texas State University |
Perkin J.S.,Kansas State University |
Shattuck Z.R.,Texas State University |
Shattuck Z.R.,BIO WEST Inc. |
Bonner T.H.,Texas State University
American Midland Naturalist | Year: 2012
Ironcolor shiner Notropis chalybaeus is generally absent from groundwater-dominated systems throughout its range; however, a relict disjunct population occurs within the spring-fed upper reaches of the San Marcos River in central Texas. We conducted monthly seine collections within the restricted 2.2 km headwater range of the species to assess food habits and reproductive life history within a unique spring-run environment. Prey items were dominated by aquatic insects including Diptera (16% by weight), Ephemeroptera (13%), and Odonata (5%), as well as terrestrial insects (9%). The population consisted of four age groups with a maximum life span of 2.5 y. Reproductive ecology showed a protracted spawning season ranging Mar.Dec. during which multiple clutches were produced. Reproductive maturity was reached at approximately 1 y (36 mm SL), mean mature oocyte diameter was ∼0.8 mm, and number of mature oocytes per clutch ranged 46326. Comparisons between ironcolor shiner populations in the San Marcos River and thermally dynamic Marshalls Creek of Pennsylvania revealed mature female size was larger (T38 = 10.48, P < 0.01) and mature oocyte diameter smaller (T38 = 16.87, P < 0.01) in the upper San Marcos River. Literature accounts regarding ironcolor shiner reproductive ecology suggest a latitudinal trade-off between reproductive season length and oocyte size. Our findings provide further evidence for the roles of photoperiod and water temperature in structuring the reproductive seasonality of spring-dwelling fishes, specifically the lack or delay of terminating cues in stenothermal waters. In this manner, aquifer depletion and alteration of thermal regimes threaten spring-dwelling fishes by disrupting naturally occurring reproductive cues. © 2012, American Midland Naturalist.
Perkin J.S.,Kansas State University |
Shattuck Z.R.,BIO WEST Inc. |
Gerken J.E.,Kansas State University |
Bonner T.H.,Texas State University
Transactions of the American Fisheries Society | Year: 2013
Burrhead Chub Macrhybopsis marconis is a species of special concern endemic to subtropical streams in south Texas. We documented life history attributes and historical patterns in abundance and distribution to aid in understanding range-wide declines of the species among the Colorado and Guadalupe-San Antonio River systems. Life history results suggest Burrhead Chub lives for 2 years, reaches sexual maturity at age-1, and spawns multiple clutches during March-September. Review of museum vouchers revealed Burrhead Chub is now missing from 26% of its historical range, including most impounded stream segments. There was a significant difference in the size of stream fragments for which Burrhead Chub is missing or still persists. Timing of many extirpations occurred after fragmentation and coincided with a record drought (1949-1959) when range-wide stream flows were exceedingly low during the Burrhead Chub reproductive season. Furthermore, extensive historical collections taken during 1950- 1961 in the Guadalupe River revealed a decline in relative abundance in upstream reaches as the drought continued. Based on these data, we hypothesize that Burrhead Chub experienced range-wide declines associated with historical drought conditions in desiccated stream fragments. Following the drought, stream flows recovered but recolonization by Burrhead Chub was blocked by impoundments in many fragments. These findings support previous linkages between stream connectivity, flow magnitude, and the persistence of fish populations while providing insight into the mechanisms driving freshwater fish declines in the plains of North America. © American Fisheries Society 2013.
PubMed | BIO WEST Inc. and Howard University
Type: Journal Article | Journal: Military medicine | Year: 2016
The following were studied in a perimortem mouse model of rapid blood loss: (a) efficacy of a prototypical micellar colloid, Intralipid 20%, (IL20), compared to albumin (b) comparison of intra-arterial and intravenous resuscitation, (c) efficacy of IL20 at a volume 2 the volume of blood removed, and (d) efficacy of oxygenated IL20 after clinical death (CD).CD, the absence of breathing and zero blood pressure (BP), was produced by removing 55% of the blood volume within 3 minutes. After CD, the chest was opened to observe ventricular contraction. IL20, Ringers lactate (RL), or albumin was infused perimortem.Without resuscitation CD occurred in 2.85 0.40 minutes. Ventricular contraction persisted 20.50 1.11 minutes after CD. RL infused immediately after CD restored breathing if given intra-arterially but not intravenously. IL20 was superior to the prototypical colloid, albumin in maintaining the BP. Increasing the volume of IL20 further increased BP. Delayed RL infusion after CD failed to restore breathing. Delayed resuscitation after CD with oxygenated IL20 restored breathing and BP.Micellar colloid is superior to the prototypical colloid albumin and can possibly be of use when signs of life are no longer present. In extremis, intra-arterial infusion is superior to intravenous infusion.