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Fast, Ultra-Trace Detection Of Juvenile Hormone Iii From Mosquitoes Using Mass Spectrometry, Cesar E. Ramirez, Marcela Nouzova, Paolo Benigni, Martin Quirke, Fernando G. Noriega, Francisco Fernandez-Lima 2017 Department of Chemistry and Biochemistry, Florida International University

Fast, Ultra-Trace Detection Of Juvenile Hormone Iii From Mosquitoes Using Mass Spectrometry, Cesar E. Ramirez, Marcela Nouzova, Paolo Benigni, Martin Quirke, Fernando G. Noriega, Francisco Fernandez-Lima

Fernando Noriega

In the present work, a new protocol for fast separation and quantification of JH III from biological samples using liquid chromatography coupled to electrospray tandem mass spectrometry is described. In particular, the proposed protocol improves existing methodologies by combining a limited number of sample preparation steps with fast LC-MS/MS detection, providing lower limits of detection and demonstrated matrix effect control, together with high inter and intraday reproducibility. A limit of detection of 8 pg/mL (0.32 pg on column) was achieved, representing a 15-fold gain in sensitivity with respect to previous LC-MS based protocols. The performance of the ...


Thermal Adaptation And Diversity In Tropical Ecosystems: Evidence From Cicadas (Hemiptera, Cicadidae), Allen F. Sanborn, James E. Heath, Polly K. Phillips, Maxine S. Heath, Fernando G. Noriega 2017 Barry University

Thermal Adaptation And Diversity In Tropical Ecosystems: Evidence From Cicadas (Hemiptera, Cicadidae), Allen F. Sanborn, James E. Heath, Polly K. Phillips, Maxine S. Heath, Fernando G. Noriega

Fernando Noriega

The latitudinal gradient in species diversity is a central problem in ecology. Expeditions covering approximately 16u549 of longitude and 21u49 of latitude and eight Argentine phytogeographic regions provided thermal adaptation data for 64 species of cicadas. We test whether species diversity relates to the diversity of thermal environments within a habitat. There are general patterns of the thermal response values decreasing in cooler floristic provinces and decreasing maximum potential temperature within a habitat except in tropical forest ecosystems. Vertical stratification of the plant communities leads to stratification in species using specific layers of the habitat. There is a decrease in ...


Allatotropin: A Pleiotropic Neuropeptide That Elicits Mosquito Immune Responses, Salvador Hernández-Martínez, Minerva Sánchez-Zavaleta, Kevin Brito, Antonia Herrera-Ortiz, Sheila Ons, Fernando G. Noriega 2017 Centro de Investigaciones Sobre Enfermedades Infecciosas, Instituto Nacional de Salud Pública

Allatotropin: A Pleiotropic Neuropeptide That Elicits Mosquito Immune Responses, Salvador Hernández-Martínez, Minerva Sánchez-Zavaleta, Kevin Brito, Antonia Herrera-Ortiz, Sheila Ons, Fernando G. Noriega

Fernando Noriega

Allatotropins (AT) are neuropeptides with pleotropic functions on a variety of insect tissues. They affect processes such as juvenile hormone biosynthesis, cardiac rhythm, oviduct and hindgut contractions, nutrient absorption and circadian cycle. The present work provides experimental evidence that AT elicits immune responses in two important mosquito disease vectors, Anopheles albimanus and Aedes aegypti. Hemocytes and an immune-competent mosquito cell line responded to AT by showing strong morphological changes and increasing bacterial phagocytic activity. Phenoloxidase activity in hemolymph was also increased in Ae. aegypti mosquitoes treated with AT but not in An. albimanus, suggesting differences in the AT-dependent immune activation ...


Heme Regulation Of Human Cystathionine Β-Synthase Activity: Insights From Fluorescence And Raman Spectroscopy, Colin L. Weeks, Sangita Singh, Peter Madzelan, Ruma Banerjee, Thomas G. Spiro 2017 University of Washington

Heme Regulation Of Human Cystathionine Β-Synthase Activity: Insights From Fluorescence And Raman Spectroscopy, Colin L. Weeks, Sangita Singh, Peter Madzelan, Ruma Banerjee, Thomas G. Spiro

Colin L. Weeks

Cystathionine β-synthase (CBS) plays a central role in cysteine metabolism, and malfunction of the enzyme leads to homocystinuria, a devastating metabolic disease. CBS contains a pyridoxal 5′- phosphate (PLP) cofactor which catalyzes the synthesis of cystathionine from homocysteine and serine. Mammalian forms of the enzyme also contain a heme group, which is not involved in catalysis. It may, however, play a regulatory role, since the enzyme is inhibited when CO or NO are bound to the heme. We have investigated the mechanism of this inhibition using fluorescence and resonance Raman spectroscopies. CO binding is found to induce a tautomeric shift ...


Modulation Of The Heme Electronic Structure And Cystathionine Β-Synthase Activity By Second Coordination Sphere Ligands: The Role Of Heme Ligand Switching In Redox Regulation, Sangita Singh, Peter Madzelan, Jay Stasser, Colin L. Weeks, Donald Becker, Thomas G. Spiro, James Penner-Hahn, Ruma Banerjee 2017 The University Of Michigan

Modulation Of The Heme Electronic Structure And Cystathionine Β-Synthase Activity By Second Coordination Sphere Ligands: The Role Of Heme Ligand Switching In Redox Regulation, Sangita Singh, Peter Madzelan, Jay Stasser, Colin L. Weeks, Donald Becker, Thomas G. Spiro, James Penner-Hahn, Ruma Banerjee

Colin L. Weeks

In humans, cystathionine β-synthase (CBS) is a hemeprotein, which catalyzes a pyridoxal phosphate (PLP)-dependent condensation reaction. Changes in the heme environment are communicated to the active site, which is ~20 Å away. In this study, we have examined the role of H67 and R266, which are in the second coordination sphere of the heme ligands, H65 and C52 respectively, in modulating the heme's electronic properties and in transmitting information between the heme and active sites. While the H67A mutation is comparable to wild-type CBS, interesting differences are revealed by mutations at the R266 site. The pathogenic mutant, R266K ...


Explore Variable Potential Ion Guide For Mass Spectrometry, Curtiss D. Hanson 2017 University of Northern Iowa

Explore Variable Potential Ion Guide For Mass Spectrometry, Curtiss D. Hanson

Curtiss D. Hanson

A variable potential ion guide for placement within the reflectron of a time-of-flight mass spectrometer includes an elongate resistive electrode placed axially within the reflectron. The electrode may be a non-conductive monofilament coated with a resistive polymer coating, with one end of the electrode coupled to a high potential source, the electrode carrying a potential gradient along its length.


Advances In Biomolecule Analysis: Ftms Of Macromolecules, Curtiss D. Hanson, Ira M. Simet, Suzanne R. Smith 2017 University of Northern Iowa

Advances In Biomolecule Analysis: Ftms Of Macromolecules, Curtiss D. Hanson, Ira M. Simet, Suzanne R. Smith

Curtiss D. Hanson

The development of Fourier transform ion cyclotron resonance (FT-ICR) as an analytical technique has opened new avenues to the analysis of high molecular weight biomolecules. Because mass analysis is based on a detection of a frequency, it is possible to obtain high resolution mass measurements without sacrificing sensitivity. The unique ability to analyze high mass ions is based in the design of a passive ExB ion trap. Although in the past, field inhomogeneities have limited this technique, recent developments in both trap designs and excitation techniques have resulted in major improvements in both sensitivity and resolution.


Ion Trap Mass Analyzer Apparatus, Methods, And Systems Utilizing One Or More Multiple Potential Ion Guide (Mpig) Electrodes, Curtiss Dwight Hanson 2017 University of Northern Iowa

Ion Trap Mass Analyzer Apparatus, Methods, And Systems Utilizing One Or More Multiple Potential Ion Guide (Mpig) Electrodes, Curtiss Dwight Hanson

Curtiss D. Hanson

In one aspect of the invention, an ion trap mass analyzer includes a variable- or multi-potential type ion guide (MPIG) assembly which has been pre-configured to produce a parabolic-type potential field. Each MPIG electrode has a resistive coating of designed characteristics. In one example the coating varies in thickness along the length of an underlying uniform substrate. The MPIG assembly can be a single MPIG electrode or an array of a plurality of MPIG electrodes. An array can facilitate delocalization for improved performance. This chemical modification of a uniform underlying substrate promotes cheaper and flexible instruments. The modified MPIG electrodes ...


Multi-Pass Reflectron Time-Of-Flight Mass Spectrometer, Curtiss D. Hanson 2017 University of Northern Iowa

Multi-Pass Reflectron Time-Of-Flight Mass Spectrometer, Curtiss D. Hanson

Curtiss D. Hanson

A novel design for a time-of-flight mass spectrometer capable of tandem mass spectrometry measurements with high resolution and high sensitivity using two variable reflectrons in a co-linear geometry. Variably switched reflectrons are oriented coaxially on opposing ends of the ion flight region allowing multiple passes of the ions along the flight region permitting high resolution, tandem mass spectrometry experiments to be performed. An electrostatic particle guide is incorporated to ensure high ion transmission efficiency in a multi-pass system. In addition to permitting the high transmission efficiency of ions, the EPG can be used in a bipolar pulsed mode to isolate ...


Algae As A New Source Of Biofuel, John C. Staley, Moises Contreras, Austin W. Jesz, Md Yusoff Mohammad Iqbal 2017 Iowa State University

Algae As A New Source Of Biofuel, John C. Staley, Moises Contreras, Austin W. Jesz, Md Yusoff Mohammad Iqbal

Mohammad Z. Iqbal

Biofuels utilizing algae as a feedstock processes the algae’s chloroplasts to transform the plant into oil that is nearly chemically identical to crude oil. Algae can grow using only available raw materials including sunlight, carbon dioxide and nutrients from wastewater. Algae can play a major role in the treatment/utilization of major wastewater and reduction of carbon dioxide in the atmosphere. High upfront costs, outdated technology, and non-existing incentives are the main reasons algae as a feedstock is currently an unpopular choice for biofuel.


A. A. Girault And His Privately Printed Papers, Marjorie C. Townes 2017 American Entomological Institute

A. A. Girault And His Privately Printed Papers, Marjorie C. Townes

The Great Lakes Entomologist

(excerpt) Alexandre ArsLne Girault was an eccentric Hymenopterist who specialized on taxonomy of the Chalcidoidea. It has been said that it is dangerous to study the parasitic Hymenoptera, for many of those who do end up in mental institutions, become alcoholics, or are, at least, a little odd. Girault was one of the odd ones.


The Importance Of Saperda Inornata And Oberea Schaumii (Coleoptera: Cerambycidae) Galleries As Infection Courts Of Hypoxylon Pruinatum In Trembling Aspen, Populus Tremuloides, John C. Nord, Fred B. Knight 2017 U. S. Department of Agriculture

The Importance Of Saperda Inornata And Oberea Schaumii (Coleoptera: Cerambycidae) Galleries As Infection Courts Of Hypoxylon Pruinatum In Trembling Aspen, Populus Tremuloides, John C. Nord, Fred B. Knight

The Great Lakes Entomologist

(excerpt) Trembling aspen, Populus tremuloides Michaux, and bigtooth aspen, P. grandidentata Michaux, are hosts of numerous species of injurious insects and microorganisms (Harrison 1959). Only a few of those organisms, however, are directly responsible for mortality of healthy trees. The fungus Hypoxylon pruinatum (Klotzsche) Cke. is most important in that respect, killing 1-2%o f the standing volume annually in the Lake States (Anderson 1964). It invades and spreads in cambial tissue, killing it and eventually the branch or stem by girdling. Initially, a canker appears as a sunken, yellowish-orange area in the bark (Anderson 1956). In a later stage ...


Bees. Their Vision, Chemical Senses, And Language By Karl Von Frisch, E C. Martin 2017 Michigan State University

Bees. Their Vision, Chemical Senses, And Language By Karl Von Frisch, E C. Martin

The Great Lakes Entomologist

BEES. THEIR VISION, CHEMICAL SENSES, AND LANGUAGE. Karl von Frisch, the University of Munich. Revised edition. Cornell University Press, Ithaca, New York and London. 157 pages. $7.50 ( 3.50), paperback $2.45.


Wing-Dimorphism In Cymindis Cribricollis Dejean And C. Neglecta Haldeman (Coleoptera: Carabidae), Andre Larochelle 2017 Bourget College

Wing-Dimorphism In Cymindis Cribricollis Dejean And C. Neglecta Haldeman (Coleoptera: Carabidae), Andre Larochelle

The Great Lakes Entomologist

(excerpt) One hundred and forty-nine specimens of Cymindis cribricollis Dejean and fifteen specimens of C. neglecta Haldeman from Quebec were examined for wingdimorphism.


Energy Balance During A Self-Sufficient, Multistage Ultramarathon, Paul A. Hough, James Earle 2017 St. Mary's University

Energy Balance During A Self-Sufficient, Multistage Ultramarathon, Paul A. Hough, James Earle

Journal of Human Performance in Extreme Environments

Endurance athletes are recommended to maintain energy balance and ensure adequate energy availability (EA) so that endurance performance is not compromised. Purpose: Describe and evaluate the energy balance of an athlete competing in a self-sufficient, multistage ultramarathon (MSU). Methods: A male endurance athlete (age 35 years; height 183.0 cm; body mass 78.4 kg; VO2max 66 ml/kg/min) volunteered to take part in this observational case study prior to competing in the Marathon des Sables (MdS) 2016. The subject self-reported energy intake (EI) by reviewing his dietary plan following each stage. Basal metabolic rate (BMR) was estimated ...


Desert Pool {If Every Desert Was Once A Sea}, Karen Miranda Abel 2017 York University

Desert Pool {If Every Desert Was Once A Sea}, Karen Miranda Abel

The Goose

Desert Pool {If every desert was once a sea} is a site-specific art project by Canadian artist Karen Miranda Abel completed in 2016 while artist-in-residence at Joya: arte + ecología, an arts-led research centre situated in an alpine desert within a national park in southern Spain. The elemental installation represents an envisioning of the ancient sea that occupied the Sierra de María-Los Vélez Natural Park millions of years before the current desert ecology, a time when its highest mountain peaks may have been islands.


C. Elegans Avoids Toxin-Producing Streptomyces Using A Seven Transmembrane Domain Chemosensory Receptor, Alan Tran, Angelina Tang, Colleen O’Loughlin, Anthony Balistreri, Eric Chang, Doris Coto Villa, Joy Li, Aruna Varshney, Vanessa Jimenez, Jacqueline Pyle, Bryan Tsujimoto, Christopher Wellbrook, Christopher Vargas, Alex Duong, Nebat Ali, Sarah Matthews, Samantha Levinson, Sarah Woldemariam, Sami Khuri, Martina Bremer, Daryl Eggers, Noelle L’Etoile, Laura Miller Conrad, Miri VanHoven 2017 San Jose State University

C. Elegans Avoids Toxin-Producing Streptomyces Using A Seven Transmembrane Domain Chemosensory Receptor, Alan Tran, Angelina Tang, Colleen O’Loughlin, Anthony Balistreri, Eric Chang, Doris Coto Villa, Joy Li, Aruna Varshney, Vanessa Jimenez, Jacqueline Pyle, Bryan Tsujimoto, Christopher Wellbrook, Christopher Vargas, Alex Duong, Nebat Ali, Sarah Matthews, Samantha Levinson, Sarah Woldemariam, Sami Khuri, Martina Bremer, Daryl Eggers, Noelle L’Etoile, Laura Miller Conrad, Miri Vanhoven

Faculty Publications, Chemistry

Predators and prey co-evolve, each maximizing their own fitness, but the effects of predator–prey interactions on cellular and molecular machinery are poorly understood. Here, we study this process using the predator Caenorhabditis elegans and the bacterial prey Streptomyces, which have evolved a powerful defense: the production of nematicides. We demonstrate that upon exposure to Streptomyces at their head or tail, nematodes display an escape response that is mediated by bacterially produced cues. Avoidance requires a predicted G-protein-coupled receptor, SRB-6, which is expressed in five types of amphid and phasmid chemosensory neurons. We establish that species of Streptomyces secrete dodecanoic ...


C. Elegans Avoids Toxin-Producing Streptomyces Using A Seven Transmembrane Domain Chemosensory Receptor, Alan Tran, Angelina Tang, Colleen T. O’Loughlin, Anthony Balistreri, Eric Chang, Doris Coto Villa, Joy Li, Aruna Varshney, Vanessa Jimenez, Jacqueline Pyle, Bryan Tsujimoto, Christopher Wellbrook, Christopher Vargas, Alex Duong, Nebat Ali, Sarah Y. Matthews, Samantha Levinson, Sarah Woldemariam, Sami Khuri, Martina Bremer, Daryl K. Eggers, Noelle L’Etoile, Laura C. Miller Conrad, Miri VanHoven 2017 San Jose State University

C. Elegans Avoids Toxin-Producing Streptomyces Using A Seven Transmembrane Domain Chemosensory Receptor, Alan Tran, Angelina Tang, Colleen T. O’Loughlin, Anthony Balistreri, Eric Chang, Doris Coto Villa, Joy Li, Aruna Varshney, Vanessa Jimenez, Jacqueline Pyle, Bryan Tsujimoto, Christopher Wellbrook, Christopher Vargas, Alex Duong, Nebat Ali, Sarah Y. Matthews, Samantha Levinson, Sarah Woldemariam, Sami Khuri, Martina Bremer, Daryl K. Eggers, Noelle L’Etoile, Laura C. Miller Conrad, Miri Vanhoven

Daryl K. Eggers

Predators and prey co-evolve, each maximizing their own fitness, but the effects of predator–prey interactions on cellular and molecular machinery are poorly understood. Here, we study this process using the predator Caenorhabditis elegans and the bacterial prey Streptomyces, which have evolved a powerful defense: the production of nematicides. We demonstrate that upon exposure to Streptomyces at their head or tail, nematodes display an escape response that is mediated by bacterially produced cues. Avoidance requires a predicted G-protein-coupled receptor, SRB-6, which is expressed in five types of amphid and phasmid chemosensory neurons. We establish that species of Streptomyces secrete dodecanoic ...


Ecological History Affects Zooplankton Community Responses To Acidification, Janet M. Fischer, Jennifer L. Klug, Anthony R. Ives, Thomas M. Frost 2017 Fairfield University

Ecological History Affects Zooplankton Community Responses To Acidification, Janet M. Fischer, Jennifer L. Klug, Anthony R. Ives, Thomas M. Frost

Jennifer L. Klug

The effects of ecological history are frequently ignored in attempts to predict community responses to environmental change. In this study, we explored the possibility that ecological history can cause differences in community responses to perturbation using parallel acidification experiments in three sites with different pH histories in the Northern Highland Lake District of Wisconsin, USA. In Trout Lake, high acid neutralizing capacity had historically buffered changes in pH. In contrast, the two basins of Little Rock Lake (Little Rock-Reference and Little Rock-Treatment) had experienced seasonal fluctuations in pH. Furthermore, the two lake basins were separated with a curtain and Little ...


Trajectories Of Zooplankton Recovery In The Little Rock Lake Whole‐Lake Acidification Experiment, Thomas M. Frost, Janet M. Fisher, Jennifer L. Klug, Shelley E. Arnott, Pamela K. Montz 2017 Fairfield University

Trajectories Of Zooplankton Recovery In The Little Rock Lake Whole‐Lake Acidification Experiment, Thomas M. Frost, Janet M. Fisher, Jennifer L. Klug, Shelley E. Arnott, Pamela K. Montz

Jennifer L. Klug

Understanding the factors that affect biological recovery from environmental stressors such as acidification is an important challenge in ecology. Here we report on zooplankton community recovery following the experimental acidification of Little Rock Lake, Wisconsin, USA. One decade following cessation of acid additions to the northern basin of Little Rock Lake (LRL), recovery of the zooplankton community was complete. Approximately 40% of zooplankton species in the lake exhibited a recovery lag in which biological recovery to reference basin levels was delayed by 1–6 yr after pH recovered to the level at which the species originally responded. Delays in recovery ...


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