SCAMP Anti-personnel Mine Roller Performance Testing

Humanistic Robotics Inc, a U.S.-based designer and manufacturer of mechanical demining machines and roboticsupport equipment, hypothesized that a well-designed roller utilized in the appropriate environments would be an important part of the mechanical demining toolkit. To test this hypothesis, HRI designed, developed and tested a novel anti-personnel mine roller—the Specialized Compact Automated Mechanical Clearance Platform Roller. This article highlights the SCAMP Roller’s unique design features, describes two testing events performed to evaluate effectiveness and discusses the test findings

Friedel–Crafts addition of indoles to nitrones promoted by trimethylsilyl trifluoromethanesulfonate

N-alkylindoles undergo Friedel–Crafts addition to aryl and secondary alkyl nitrones in the presence of trimethylsilyl trifluoromethanesulfonate and a trialkylamine to produce 3-(1- (silyloxyamino)alkyl)indoles. Spontaneous conversion to the bisindolyl(aryl)methanes, which is thermodynamically favored for nitrones derived from aromatic aldehydes, is suppressed under the reaction conditions. The silyloxyamino group can be deprotected with tetrabutylammonium fluoride to yield the hydroxylamine

Prospectus, October 25, 1984

NICARAGUAN ISSUES PRESENTED; How important is one vote?; Republicans believe their policies are best; Dear Prospectus staff; Democrats believe they have the answers; Busing of private school students Who will foot the bill?; Library director\u27s son honored Johnson is All-American; Library undergoes computerization; PC Happenings; Women\u27s workshop turns to life choices; Family program offered in 4 parts; Health professionals workshop set; Board considers program additions; The Bowling Pin; Wife abuse still widespread problem; Did you know...TV Trivia; Gammon designs for bazaar; International students plan Halloween party; Block talented in diverse fields; Creative Corner...Especially for you!!; Doom Story-the climax draws near; Nuclear Weapons Freeze; Rejoice the Poet; Sacred Love; The Little Red Dog; The Unopened Gate; One More Time; The Run; RS 1981-82; Decisions; Watching; The Widower; Classifieds; Farrah can act; The Burning Bed alters opinions; Tina\u27s hot as a solo; Joan\u27s newest lacks punch; Why is Harry so much trouble; Furs possess unique style; Motherhood makes humorous reading; Budget bin; Lady Cobras compile 7-1 record in tournament; Clifton, Sullivan guest on Cobra Rap show; Gold defeat Green in 4 games; Peterson to nationalshttps://spark.parkland.edu/prospectus_1984/1007/thumbnail.jp

Life-history plasticity of riparian annual plants adapted to extreme variations in water level: mesocosm experiments

The riparian zones of reservoirs associated with regulated rivers in China experience annual fluctuations in water level of up to 30 m that may vary in timing from year to year. Few plant species can tolerate such hydrological perturbation but short-lived riparian annuals might be evolutionarily pre-adapted to such conditions. This study investigated plasticity of life history in four annual species: one typically associated with free-flowing rivers (Panicum bisulcatum) and three that colonize reservoir margins (Cyperus michelianus, Fimbristylis miliacea and Eclipta prostrata). We found that all four species produced non-dormant seeds that survived prolonged submergence; germination percentage was independent of the time of exposure by receding waters. Although growth was reduced as a result of shorter growing seasons, all four species completed their life cycles and produced seeds before winter. In addition, P. bisulcatum and C. michelianus allocated biomass to seed production, at the expense of roots and stems, in response to later establishment. All species responded to later establishment with a reduced vegetative growth period before seed production. C. michelianus, F. miliacea and E. prostrata could also delay the onset of flowering time by up to 2 months. P. bisulcatum, a plant that can flower only after exposure to short days, consequently had a fixed flowering time and could accommodate delayed establishment only with a progressively shorter period of vegetative growth. This lower flexibility might explain its absence from reservoir margins. The conceptual framework presented here offers a tool to predict the establishment of vegetation under hydrological disturbance in riparian environments and thereby provides insights into improved restoration practice

Terrestrial Reserve Networks Do Not Adequately Represent Aquatic Ecosystems

Las áreas protegidas son una piedra angular de la conservación y han sido diseñadas principalmente alrededor de atributos terrestres. Las especies y ecosistemas dulceacuícolas se encuentran en peligro, pero la efectividad de las áreas protegidas existentes para representar las características dulceacuícolas es poco conocida. Utilizando las aguas interiores de Michigan como un caso de prueba, cuantificamos la cobertura de cuatro atributos dulceacuícolas clave (humedales, zonas ribereñas, recarga de agua subterránea y especies raras) en las tierras conservadas y las comparamos con la representación de los atributos terrestres. Los humedales estaban incluidos en las áreas protegidas más a menudo que lo esperado por azar, pero las zonas ribereñas estuvieron insuficientemente representadas en todas las tierras protegidas (GAP1–3), particularmente en manantiales y ríos grandes. Sin embargo, las zonas ribereñas estuvieron bien representadas en las tierras con protección estricta (GAP 1–2) debido a la contribución del Programa Nacional de Ríos Silvestres y Escénicos. La representación de áreas de recarga de aguas subterráneas generalmente fue proporcional al área de la red de reservas dentro de cuencas hidrológicas, aunque un sitio importante de recarga asociado con algunos de los ríos más valiosos en Michigan estaba casi totalmente desprotegido. La representación de especies en áreas protegidas difirió significativamente entre las especies acuáticas obligadas, de humedales y terrestres, con una representación generalmente mayor para las especies terrestres y menor para las acuáticas. Nuestros resultados ilustran la necesidad de evaluar y atender la representación de los atributos dulceacuícolas dentro de las áreas protegidas y el valor de ampliar el análisis de brechas y otras evaluaciones de áreas protegidas para incluir los procesos ecosistémicos claves que son requisito para la conservación a largo plazo de especies y ecosistemas. Concluimos que las redes de áreas protegidas orientadas al medio terrestre proporcionan una red de seguridad débil para los atributos acuáticos, lo que significa que se requiere planeación y manejo complementario tanto para objetivos de conservación dulceacuícolas como terrestres.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/79138/1/COBI_1460_sm_AppendixS3.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/79138/2/COBI_1460_sm_AppendixS1.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/79138/3/j.1523-1739.2010.01460.x.pd

Early Vegetation Development on an Exposed Reservoir: Implications for Dam Removal

The 4-year drawdown of Horsetooth Reservoir, Colorado, for dam maintenance, provides a case study analog of vegetation response on sediment that might be exposed from removal of a tall dam. Early vegetation recovery on the exposed reservoir bottom was a combination of (1) vegetation colonization on bare, moist substrates typical of riparian zones and reservoir sediment of shallow dams and (2) a shift in moisture status from mesic to the xeric conditions associated with the pre-impoundment upland position of most of the drawdown zone. Plant communities changed rapidly during the first four years of exposure, but were still substantially different from the background upland plant community. Predictions from the recruitment box model about the locations of Populus deltoides subsp. monilifera (plains cottonwood) seedlings relative to the water surface were qualitatively confirmed with respect to optimum locations. However, the extreme vertical range of water surface elevations produced cottonwood seed regeneration well outside the predicted limits of drawdown rate and height above late summer stage. The establishment and survival of cottonwood at high elevations and the differences between the upland plant community and the community that had developed after four years of exposure suggest that vegetation recovery following tall dam removal will follow a trajectory very different from a simple reversal of the response to dam construction, involving not only long time scales of establishment and growth of upland vegetation, but also possibly decades of persistence of legacy vegetation established during the reservoir to upland transition

The role of river morphodynamic disturbance and groundwater hydrology as driving factors of riparian landscape patterns in mediterranean rivers

Original ResearchFluvial disturbances, especially floods and droughts, are the main drivers of the successional patterns of riparian vegetation. Those disturbances control the riparian landscape dynamics through the direct interaction between flow and vegetation. The main aim of this work is to investigate the specific paths by which fluvial disturbances, distributed by its components of groundwater hydrology (grndh) and morphodynamic disturbance (mrphd), drive riparian landscape patterns as characterized by the location (position in the river corridor) and shape (physical form of the patch) of vegetation patches in Mediterranean rivers. Specifically, this work assesses how the different components of fluvial disturbances affect these features in general and particularly in each succession phase of riparian vegetation. grndh and mrphd were defined by time and intensity weighted indexes calculated, respectively, from the mean annual water table elevations and the annual maximum instantaneous discharge shear stresses of the previous decade. The interactions between riparian landscape features and fluvial disturbances were assessed by confirmatory factor analysis using structural equation modeling. Two hypothetical models for patch location and shape were conceptualized and tested against empirical data collected from 220 patches at four different study sites. Both models were successfully fitted, meaning that they adequately depicted the relationships between the variables. Furthermore, the models achieved a good adjustment for the observed data, based on the evaluation of several approximate fit indexes. The patch location model explained approximately 80% of the patch location variability, demonstrating that the location of the riparian patches is primarily driven by grndh, while the mrphd had very little effect on this feature. In a multigroup analysis regarding the succession phases of riparian vegetation, the fitted model explained more than 68% of the variance of the data, confirming the results of the general model. The patch shape model explained nearly 13% of the patch shape variability, in which the disturbances came to have less influence on driving this feature. However, grndh continues to be the primary driver of riparian vegetation between the two disturbance factors, despite the proportional increase of the mrphd effect to approximately a third of the grndh effectinfo:eu-repo/semantics/publishedVersio

The natural wood regime in rivers

International audienc

Analyzing the Impacts of Dams on Riparian Ecosystems: A Review of Research Strategies and Their Relevance to the Snake River Through Hells Canyon

River damming provides a dominant human impact on river environments worldwide, and while local impacts of reservoir flooding are immediate, subsequent ecological impacts downstream can be extensive. In this article, we assess seven research strategies for analyzing the impacts of dams and river flow regulation on riparian ecosystems. These include spatial comparisons of (1) upstream versus downstream reaches, (2) progressive downstream patterns, or (3) the dammed river versus an adjacent free-flowing or differently regulated river(s). Temporal comparisons consider (4) pre- versus post-dam, or (5) sequential post-dam conditions. However, spatial comparisons are complicated by the fact that dams are not randomly located, and temporal comparisons are commonly limited by sparse historic information. As a result, comparative approaches are often correlative and vulnerable to confounding factors. To complement these analyses, (6) flow or sediment modifications can be implemented to test causal associations. Finally, (7) process-based modeling represents a predictive approach incorporating hydrogeomorphic processes and their biological consequences. In a case study of Hells Canyon, the upstream versus downstream comparison is confounded by a dramatic geomorphic transition. Comparison of the multiple reaches below the dams should be useful, and the comparison of Snake River with the adjacent free-flowing Salmon River may provide the strongest spatial comparison. A pre- versus post-dam comparison would provide the most direct study approach, but pre-dam information is limited to historic reports and archival photographs. We conclude that multiple study approaches are essential to provide confident interpretations of ecological impacts downstream from dams, and propose a comprehensive study for Hells Canyon that integrates multiple research strategies

Climate Change Impacts on Groundwater and Dependent Ecosystems - in press

[EN] Aquifers and groundwater-dependent ecosystems (GDEs) are facing increasing pressure from water consumption, irrigation and climate change. These pressures modify groundwater levels and their temporal patterns and threaten vital ecosystem services such as arable land irrigation and ecosystem water requirements, especially during droughts. This review examines climate change effects on groundwater and dependent ecosystems. The mechanisms affecting natural variability in the global climate and the consequences of climate and land use changes due to anthropogenic influences are summarised based on studies from different hydrogeological strata and climate zones. The impacts on ecosystems are discussed based on current findings on factors influencing the biodiversity and functioning of aquatic and terrestrial ecosystems. The influence of changes to groundwater on GDE biodiversity and future threats posed by climate change is reviewed, using information mainly from surface water studies and knowledge of aquifer and groundwater ecosystems. Several gaps in research are identified. Due to lack of understanding of several key processes, the uncertainty associated with management techniques such as numerical modelling is high. The possibilities and roles of new methodologies such as indicators and modelling methods are discussed in the context of integrated groundwater resources management. Examples are provided of management impacts on groundwater, with recommendations on sustainable management of groundwaterThe preparation of this review was partly funded by EC 7th framework Project GENESIS (Contract Number 226536).Klove, B.; Ala-Aho, P.; Bertrand, G.; Gurdak, JJ.; Kupfersberger, H.; Kværner, J.; Muotka, T.... (2014). Climate Change Impacts on Groundwater and Dependent Ecosystems - in press. Journal of Hydrology. 518(Part B):250-266. https://doi.org/10.1016/j.jhydrol.2013.06.037S250266518Part