The Influence of Landscape Factors on Black-Tailed Prairie Dog (Cynomys ludovicianus) Colony Persistence in Northwest Kansas

The black-tailed prairie dog (Cynomys ludovicianus) is a colonial and fossorial rodent species that serves as an ecosystem engineer and keystone species in North America’s grasslands. Black-tailed prairie dogs historically ranged from northern Mexico to southern Canada, and from eastern Nebraska to the foothills of the Rocky Mountains. However, with the loss and fragmentation of grasslands, introduction of Sylvatic plague (Yersinia pestis), and control measures such as poisoning and shooting, black-tailed prairie dogs are limited to less than 5 percent of their historical range. In this study, I examined how colony area, location, isolation, and surrounding land cover affected the persistence of black-tailed prairie dog colonies in northwest Kansas from 2005-2015. Using aerial imagery from the National Agricultural Imagery Program (NAIP), I attempted to map every black-tailed prairie dog colony in northwest Kansas from 2005-2015. I used generalized linear models and Akaike’s information criterion (AIC) to determine which factors influenced colony persistence. I found that the number of black-tailed prairie dog colonies and total area occupied by colonies varied from 2005-2015, with both experiencing a sharp decline from 2014-2015. While the number of colony extinctions per year also varied, the number of new colonies established steadily decreased over the study period. The logarithmic transformation of colony area was the most important variable to colony persistence, occurring in all of the best 25 models. The longitude of the colony was the second most important factor, occurring in 24 of the best 25 models. Determining which factors have the greatest impact on black-tailed prairie dog colony persistence is crucial for the development of conservation management plans for this declining species

Production of biopolymers and synthons from lignocellulosic wastes

Agricultural and forestry residues, also known as lignocellulosic residues, have a unique potential based on their quantity and structure for the production of renewable energy and molecules, inorder to solve the issues raised by the increasing scarcity of fossil hydrocarbons and the environmental disorder caused by their use. Lignocellulosic biomasses are essentially made ofcellulose, hemicelluloses and lignin. Fractionation and purification of these three compounds are necessary for their valorization as substitutes of fossil hydrocarbons. In the first place, this studydescribed the chemical fractionation of lignocellulose under acidic and alkaline conditions, and their related purification pathways. The experimental work was carried out on two raw materials:sugarcane bagasse and sunflower oil cake. A thorough characterization of the raw materials as well as the acid and alkaline extracts produced from these materials was performed. The purification steps focused on the sugarcane bagasse mild alkaline extract. Indeed, sugarcane bagasse can be considered a model lignocellulosic biomass and the purification of lignocellulosicmild alkaline extract has not been widely studied despite the numerous assets of this fractionation process. Membrane filtration and elution chromatography on strong acid cationic exchange resins were assessed individually then combined, for the separation of the five main pools of molecules that constitute the extract: lignin oligomers, sugar oligomers, phenolic monomers, acetic acid and inorganic salts. Ultrafiltration trials run on several membranes under various filtration conditions showed that lignin and sugar oligomers, recovered in the retentate, were separated from phenolicmonomers, acetic acid and inorganic salts, recovered in the permeate. A hollow fiber membrane of 10 kDa in polysulfone exhibited the best separation performance and was selected for further trials in concentration and diafiltration modes. Elution chromatography tests using water as eluent and various strong acid cationic exchange resins resulted in the production of a very pure lignin andsugar oligomers fraction with a macroporous-type resin, whereas a gel-type resin led to the separation of phenolic monomers from each other depending on the presence or absence in their structure of a carboxyl group. From a sugarcane bagasse mild alkaline extract, an integrated purification process was developed combining membrane filtration then chromatography on the permeate and precipitation by acid addition on the retentate. It resulted in the production of four purified fractions: phenolic monomers with a carboxyl group, inorganic salts and phenolicmonomers without carboxyl group, lignin oligomers, and sugar oligomer

Do readers believe what they see? : reader acceptance of image manipulation

The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file.Title from PDF of title page (University of Missouri--Columbia, viewed on November 19, 2009).Thesis advisor: David Rees.M.A. University of Missouri--Columbia 2009.This study uses a random public sample to measure the level of acceptance the public has of various kinds of image adjustment/manipulation, to discover how frequently the respondents believe the same manipulations are performed on the news images in the local daily newspaper and how much they trust those images to truthfully depict the scene photograph. The study also looks for a correlation between a person's familiarity with imaging software and that person's views on, or expectations of, digital manipulation of the news images. The findings indicate the public's acceptance of the various digital adjustments mirrors the profession's though the respondents were less accepting of burning and dodging. The findings also show that many of the readers believe drastic image manipulations are performed far more frequently than they actually are. No correlation was found between a person's familiarity with imaging software and the level of trust assigned to news images.Includes bibliographical references

L’assertion en discours réfléchi tell oneself versus say to oneself

The purpose of this paper is to discuss the characteristics of two phrases: say to oneself / tell oneself. After presenting the results of a corpus study of these phrases, we shall explore the distinction that can be made in the types of speech they introduce. We will attempt to show that tell oneself is used when the content of the reported speech seems doubtful and thus expresses a point of view while say to oneself seems more objective

Oxa- and Azacycle-formation via Migrative Cyclization of Sulfonylalkynol and Sulfonylalkynamide with NHeterocyclic Carbene

An N-heterocyclic carbene promotes cyclization of sulfonylalkynols and sulfonylalkynamides that accompanies 1,2-migration of the sulfonyl groups. This reaction provides a novel access to oxa- and azacycles possessing a pendent vinyl sulfone functionality, which in turn is amenable for further transformations

Separation of sugarcane bagasse mild alkaline extract components by ultrafiltration – Membrane screening and effect of filtration parameters

Mild alkaline treatment (1.5% NaOH (w/v), solid:liquid ratio of 1:20, 60 °C, 6 h) of sugarcane bagasse (SCB) produced an extract composed of hemicelluloses, lignin, phenolic monomers and acetic acid. The purification of this extract, usually considered a by-product in lignocellulosic biorefineries, is of major importance to give value to the whole mild alkaline fractionation process. Ultrafiltration was assessed to separate the components of the SCB alkaline extract which is a prerequisite for their further valorization. The permeate flux and the retention of the extract components were studied on seven membranes (polysulfone hollow fiber and ceramic tubular) with different molecular weight cut-offs, under various operating conditions. On all the membranes tested, oligomers of lignin and hemicelluloses were separated from salts, phenolic monomers and acetic acid. The 10 kDa polysulfone hollow fiber membrane presented the highest lignin and hemicelluloses retention, exceeding 85 and 90%, respectively, regardless of shear rate and with a limited influence of transmembrane pressure. For salts, acetic acid and phenolic monomers, retention levels of about 0–10% were recorded for this membrane. At 2.8 bar and at 20 °C, the permeate flux reached 16 L/h/m2 and the critical flux was not reached

Sugarcane bagasse mild alkaline fractionation and production of purified fractions by pulse chromatography with water

Sugarcane bagasse (SCB) was treated under mild alkaline conditions (solid:liquid ratio of 1:20 (w/v), 1.5% NaOH (w/v), 60 °C, 6 h) to fractionate the lignocellulose in order to produce a typical mild alkaline extract from a lignocellulosic biomass. The solid residue was enriched in cellulose, while the SCB alkaline extract contained lignin and hemicelluloses, but also inorganic salts, five phenolic monomers and acetic acid. After concentration of the alkaline extract by evaporation, low pressure chromatography with water as eluent was performed to produce purified fractions. Two different strong acid cation (SAC) exchange resins were tested: one gel-type resin and one macroporous-type resin. The lignin and hemicelluloses were separated from the inorganic salts by the gel-type SAC exchange resin. On this resin, the phenolic monomers were partitioned regarding the presence or absence in their structure of a carboxyl group. On the macroporous-type SAC exchange resin, the largest sugar oligomers and lignin oligomers were obtained in a fraction free of inorganic salts, phenolic monomers and acetic acid

Franchir l’écart

L’étude des causatifs de mouvement, particulièrement en tant qu’ils sont associés à un lieu de passage, et de leurs variations aussi bien intralingues que contrastives, permet de corroborer les schémas contrastifs des causatifs de type « make » et « have », qui veulent que la relation fondamentale de l’anglais soit d’ordre modal et télique et la relation fondamentale du français soit d’ordre modal et intersubjectif.The study of verbs like “to lead” / “mener”, “conduire” and “to open into/onto” / “s'ouvrir sur” when they are associated with passage-ways or openings (road / chemin, door / porte, window / fenêtre) proves that they imply the same underlying operations as classical causative constructions involving “have” and “make”; the basic difference between English and French is that English focuses on modality and telicity whereas French focuses on modality and intersubjective relation

Mechanistic Support for Intramolecular Migrative Cyclization of Propargyl Sulfones Provided by Catalytic Asymmetric Induction with a Chiral Counter Cation Strategy

We previously reported an intramolecular migrative cyclization of propargylsufones and sulfonylalkynamides giving oxa- and azacycles, respectively. To confirm the postulated reaction mechanism, the reaction was conducted with chiral nucleophiles such as N-heterocyclic carbenes, phosphines, and pyridines, or with sulfinate anions and chiral cations. As expected, migrative cyclization proceeded to give the enantiomerically enriched products. These results strongly support the postulated mechanism and provide the first example of the asymmetric version of this reaction

L’assertion en discours réfléchi tell oneself versus say to oneself

The purpose of this paper is to discuss the characteristics of two phrases: say to oneself / tell oneself. After presenting the results of a corpus study of these phrases, we shall explore the distinction that can be made in the types of speech they introduce. We will attempt to show that tell oneself is used when the content of the reported speech seems doubtful and thus expresses a point of view while say to oneself seems more objective