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Artigo Revisado por pares

Jean‐Charles Fontes, Roberto Gonfiantini,

... outlet in the North-Western Sahara (Gara Diba Guelta and el Melah Sebkha) has been studied. A ... process of these basins (4 months for the Guelta and 6 months for the Sebkha) showed a ... of the experimental values was developed for the Guelta evaporating water. It provided us with an estimate ...

Tópico(s): Water management and technologies

1967 - Elsevier BV | Earth and Planetary Science Letters

Artigo Acesso aberto Revisado por pares

Cândida Gomes Vale, Stuart L. Pimm, José Carlos Brito,

... predictors of species number's present in each guelta through a multiple regression model. We ranked gueltas ... the percentage of endemics and threats to each guelta. Within a mere aggregate extent of 43 ha, ... respectively. The number of species present in each guelta increased with the primary productivity and area of ...

Tópico(s): Wildlife Ecology and Conservation

2015 - Public Library of Science | PLoS ONE

Artigo Acesso aberto Revisado por pares

Sébastien Trape,

... was unclear, B. macrops was collected in Bachikere guelta. The toad Amietophrynus regularis was collected in Ounianga ... incertain, B. macrops a été collecté dans la guelta de Bachikéré. Le crapaud Amietophrynus regularis a été ...

Tópico(s): Aquatic Ecosystems and Biodiversity

2013 - Elsevier BV | Comptes Rendus Biologies

Artigo Revisado por pares

Lucia Memmi,

... upper Jurassic and lower Cretaceous sequence in the Guelta wadi basin, northeastern Tunisia, includes a richly fossiliferous ...

Tópico(s): Paleontology and Stratigraphy of Fossils

1965 - EDP Sciences | BSGF – Earth Sciences Bulletin

Artigo Revisado por pares

Randall S. Wentsel, Mark A. Guelta,

Abstract Tests of the avoidance of brass powder (70% Cu, 30% Zn) contaminated soils by the earthworm Lumbricus terrestris at concentrations ranging from 0 to 200 μg/g were conducted. Avoidance was significant (p < 0.001) at brass concentrations as low as 38 μg/g. Avoidance was found to be a more sensitive indicator of the impact of brass powder on the worms than sublethal effects measured by weight loss.

Tópico(s): Invertebrate Taxonomy and Ecology

1988 - Wiley | Environmental Toxicology and Chemistry

Artigo Acesso aberto Revisado por pares

Sébastien Trape,

... et-Tefla pools have become ephemeral. The Hamdoun guelta appears to be highly endangered. The fish populations ...

Tópico(s): Transboundary Water Resource Management

2009 - Public Library of Science | PLoS ONE

Artigo Revisado por pares

Mohamed Sahnouni, Jan van der Made, Melanie Everett,

... Beni Fouda intramontane basin, the Oued Boucherit area (Guelta Zerga, North East Algeria) hosts a unique succession ...

Tópico(s): Geology and Paleoclimatology Research

2009 - Elsevier BV | Quaternary International

Artigo Acesso aberto Revisado por pares

Wieslaw Swietnicki, Daniel O. Carmany, Michael Retford, Mark A. Guelta, Russell Dorsey, Joel A. Bozue, Michael S. Lee, Mark A. Olson,

Yersinia pestis is a Gram negative zoonotic pathogen responsible for causing bubonic and pneumonic plague in humans. The pathogen uses a type III secretion system (T3SS) to deliver virulence factors directly from bacterium into host mammalian cells. The system contains a single ATPase, YscN, necessary for delivery of virulence factors. In this work, we show that deletion of the catalytic domain of the yscN gene in Y. pestis CO92 attenuated the strain over three million-fold in the Swiss-Webster mouse ...

Tópico(s): Escherichia coli research studies

2011 - Public Library of Science | PLoS ONE

Artigo Revisado por pares

Mohamed Sahnouni, Djillali Hadjouis, Jan van der Made, Abdelkader Derradji, Antoni Canals, Mohamed Medig, Hocine Bellahreche, Zoheir Harichane, Merouane Rabhi,

... Beni Fouda intramontane basin, the Oued Boucherit area (Guelta Zerga, North East Algeria) hosts a unique succession ...

Tópico(s): Evolution and Paleontology Studies

2004 - Elsevier BV | Journal of Human Evolution

Artigo Revisado por pares

Peng Li, Su‐Young Moon, Mark A. Guelta, Steven P. Harvey, Joseph T. Hupp, Omar K. Farha,

Immobilized enzymes typically have greater thermal and operational stability than their soluble form. Here we report that for the first time, a nerve agent detoxifying enzyme, organophosphorus acid anhydrolase (OPAA), has been successfully encapsulated into a water-stable zirconium metal–organic framework (MOF). This MOF features a hierarchical mesoporous channel structure and exhibits a 12 wt % loading capacity of OPAA. The thermal and long-term stabilities of OPAA are both significantly enhanced after ...

Tópico(s): Dendrimers and Hyperbranched Polymers

2016 - American Chemical Society | Journal of the American Chemical Society

Artigo Acesso aberto Revisado por pares

Peng Li, Su‐Young Moon, Mark A. Guelta, Lu Lin, Diego A. Gómez‐Gualdrón, Randall Q. Snurr, Steven P. Harvey, Joseph T. Hupp, Omar K. Farha,

We report the synthesis and characterization of a water-stable zirconium metal-organic framework (MOF), NU-1003, featuring the largest mesoporous aperture known for a zirconium MOF. This material has been used to immobilize the nerve agent hydrolyzing enzyme, organophosphorus acid anhydrolase (OPAA). The catalytic efficiency of immobilized OPAA in nanosized NU-1003 is significantly increased compared to that of OPAA immobilized in microsized NU-1003 and even exceeds that of the free OPAA enzyme. This ...

Tópico(s): Dendrimers and Hyperbranched Polymers

2016 - American Chemical Society | ACS Nano

Artigo Acesso aberto Revisado por pares

S.M. Bester, Mark A. Guelta, Jonah Cheung, Mark D. Winemiller, Su Y. Bae, James M. Myslinski, Scott D. Pegan, J.J. Height,

Over 50 years ago, the toxicity of irreversible organophosphate inhibitors targeting human acetylcholinesterase (hAChE) was observed to be stereospecific. The therapeutic reversal of hAChE inhibition by reactivators has also been shown to depend on the stereochemistry of the inhibitor. To gain clarity on the mechanism of stereospecific inhibition, the X-ray crystallographic structures of hAChE inhibited by a racemic mixture of VX (PR/S) and its enantiomers were obtained. Beyond identifying hAChE structural ...

Tópico(s): Pesticide Exposure and Toxicity

2018 - American Chemical Society | Chemical Research in Toxicology

Paratexto Revisado por pares

S.M. Bester, Guelta, Jonah Cheung, Winemiller, Su Y. Bae, James M. Myslinski, Scott D. Pegan, J.J. Height,

Over 50 years ago, the toxicity of irreversible organophosphate inhibitors targeting human acetylcholinesterase (hAChE) was observed to be stereospecific. The therapeutic reversal of hAChE inhibition by reactivators has also been shown to depend on the stereochemistry of the inhibitor. To gain clarity on the mechanism of stereospecific inhibition, the X-ray crystallographic structures of hAChE inhibited by a racemic mixture of VX (P R/S) and its enantiomers were obtained. Beyond identifying hAChE ...

Tópico(s): Pesticide Exposure and Toxicity

2018 - American Chemical Society | Chemical Research in Toxicology

Artigo Revisado por pares

Randall S. Wentsel, Mark A. Guelta,

Abstract The earthworm Lumbricus terrestris was exposed to brass powder (70% Cu, 30% Zn) contaminated soils at concentrations ranging from 0 to 430 μg/g. A 14-d LC50 of 190 μg/g with 95% fiducial limits of 169 and 220 μg/g was determined. Sublethal effects, measured as weight loss, were significantly different (p < .05) from the control at 120 μg/g and above.

Tópico(s): Invertebrate Taxonomy and Ecology

1987 - Wiley | Environmental Toxicology and Chemistry

Artigo Revisado por pares

Hugh R. Carlon, Mark A. Guelta, Bernard V. Gerber,

For many decades dioctyl phthalate (DOP), a common industrial material, has been used by the U.S. Army and other agencies to simulate aerosol behavior in nondestructive gas mask and filter serviceability testing, and for related test purposes. Techniques are completely standardized. But DOP is now considered to be a potentially hazardous material. The research reported here, which was performed using ATI Q-127 and TDA-100 “hot smoke” aerosol penetrometer test machines, identified relatively innocuous, ...

Tópico(s): Engineering and Material Science Research

1991 - Taylor & Francis | Aerosol Science and Technology

Artigo Acesso aberto Revisado por pares

Henri J. Dumont,

... and one without fish, zooplankton migrated vertically.The guelta with fish had a very impoverished zooplankton, mainly ... copepods.They showed a strong diurnal migration.The guelta without fish had Daphnia, Asplanchna, and the fairy ...

Tópico(s): Transboundary Water Resource Management

2019 - | Limnetica

Artigo Revisado por pares

Anton Brancelj,

... Groundwater samples collected in the vicinity of one guelta contained Syncarida, Isopoda, and Copepoda. Among the latter, ...

Tópico(s): Aquatic Ecosystems and Phytoplankton Dynamics

2015 - Q15088586 | Zootaxa

Artigo Revisado por pares

Rodrigo de Balbín Behrmann,

Tópico(s): Language, Linguistics, Cultural Analysis

1973 - Spanish National Research Council | Trabajos de Prehistoria

Artigo Acesso aberto Revisado por pares

Feifei Guo, Henri J. Dumont,

... the Sahara desert. One species, from a freshwater guelta on the south flanks of the Tibesti (D. ...

Tópico(s): Marine Invertebrate Physiology and Ecology

2014 - Q15088586 | Zootaxa

Artigo Acesso aberto Revisado por pares

Bouchiba Guelta, Redouane Tlemsani, Samira Chouraqui, Mohamed Benouis,

This paper presents multi-modal biometric authentication approach using gait and electrocardiogram (ECG) signals, which can diminish the drawback of unimodal biometric approach as well as to improve authentication system performance.In acquisition phase, data sets are collected from three different databases, ECG-ID, MIT-BIH Arrhythmia database and UCI Machine Learning Repository (Gait).In Feature extraction phase of both signals (ECG and Gait) is performed by using 1D-local binary pattern.Features ...

Tópico(s): Non-Invasive Vital Sign Monitoring

2019 - Intelligent Networks and Systems Society | International journal of intelligent engineering and systems

Artigo Revisado por pares

J.R. McGuire, S.M. Bester, Mark A. Guelta, Jonah Cheung, Caroline Langley, Mark D. Winemiller, Sue Y. Bae, Vanessa L. Funk, James M. Myslinski, Scott D. Pegan, J.J. Height,

The recent use of organophosphate nerve agents in Syria, Malaysia, Russia, and the United Kingdom has reinforced the potential threat of their intentional release. These agents act through their ability to inhibit human acetylcholinesterase (hAChE; E.C. 3.1.1.7), an enzyme vital for survival. The toxicity of hAChE inhibition via G-series nerve agents has been demonstrated to vary widely depending on the G-agent used. To gain insight into this issue, the structures of hAChE inhibited by tabun, sarin, ...

Tópico(s): Computational Drug Discovery Methods

2021 - American Chemical Society | Chemical Research in Toxicology

Artigo Acesso aberto Revisado por pares

Ibrahim Elkhalil Behmene, Bachir Bouiadjra Benabdallah, Mohamed Daoudi,

... Mudfish Clarias anguillaris (Linnaeus, 1758) (Siluriformes Clariidae), to Guelta Ifni (Illizi) an integral part of the Tassili ...

Tópico(s): Aquatic Ecosystems and Biodiversity

2020 - Edizioni Danaus, Palermo | BIODIVERSITY JOURNAL

Editorial Revisado por pares

Shengnan Zhou, Danyou Hu, Zhirui Fang, Guiyang Zhang,

... Crossref, Medline, Google Scholar11. Li P, Moon SY, Guelta MA, Harvey SP, Hupp JT, Farha OK. Encapsulation ...

Tópico(s): Luminescence and Fluorescent Materials

2021 - Future Medicine | Nanomedicine

Artigo Revisado por pares

Alain Thiéry, D. Christopher Rogers,

... is described from a temporary water body, or guelta, in the Sahara Desert near the Tadrart mountains, ...

Tópico(s): Marine Biology and Ecology Research

2022 - Oxford University Press | Journal of Crustacean Biology

Artigo Revisado por pares

Omer Alrwais,

A guelta is a small body of water that accumulates in the wadis, or drainage channels of the Sahara ... ways, such as mapping the size of a Guelta or predicting where water will flow during devastating ... this paper we review published work that combined Guelta determination with GIS or remote sensing technology. The ... on surface water detection (wetlands) and applied to Guelta research.

Tópico(s): Historical and Architectural Studies

2023 - Associação Interciencia | Interciencia

Capítulo de livro

Joseph DeFrank, Mark A. Guelta, Steven P. Harvey, Ilona J. Fry, James P. Earley, F. Stephen Lupton,

Tópico(s): Pesticide Exposure and Toxicity

2000 - Springer Nature (Netherlands) | NATO science series. Partnership sub-series 1, Disarmament technologies

Artigo Revisado por pares

Jari Haimi, Sirkku Paavola,

... at Amsterdam, Amsterdam, The Netherlands. 9 Wentsel R, Guelta M. 1988. Avoidance of brass powder-contaminated soil ...

Tópico(s): Insect and Arachnid Ecology and Behavior

1998 - Wiley | Environmental Toxicology and Chemistry

Artigo Acesso aberto Revisado por pares

Samir Belmahi, Mohamed Zidour, Haddi Abdelkader,

... the control mortar based on quarry sand from Guelta, Algeria, so, the mixture of 30 to 50% ...

Tópico(s): Materials Engineering and Processing

2020 - National Council for Scientific Research | Lebanese Science Journal