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1.
New Dir Stud Leadersh ; 2018(158): 9-22, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29575732

RESUMEN

Mentoring, coaching, and advising are often confused as similar interactions with developmental intent, yet their scope, purpose, and utility in leadership development are distinct. The purpose of this chapter is to provide clarity as to what constitutes mentoring, coaching, and advising for leadership development and to compare and contrast each relationship type.


Asunto(s)
Docentes , Liderazgo , Tutoría , Universidades , Adulto , Humanos , Adulto Joven
2.
New Dir Stud Leadersh ; 2018(158): 5-8, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29575735
3.
New Dir Stud Leadersh ; 2017(155): 59-70, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28834312

RESUMEN

This chapter explores the potential and promise of student organization advisors in facilitating student leader development. Through exploration of key aspects of institutional support, the author identifies ways that advisors of all backgrounds contribute to the teaching and learning experiences of students.


Asunto(s)
Liderazgo , Organizaciones , Estudiantes , Universidades , Adolescente , Adulto , Humanos , Adulto Joven
4.
Environ Toxicol Chem ; 32(1): 207-21, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23071077

RESUMEN

Sediment toxicity tests were conducted to assess potential effects of contaminants associated with coal mining or natural gas extraction activities in the upper Tennessee River basin and eastern Cumberland River basin in the United States. Test species included two unionid mussels (rainbow mussel, Villosa iris, and wavy-rayed lampmussel, Lampsilis fasciola, 28-d exposures), and the commonly tested amphipod, Hyalella azteca (28-d exposure) and midge, Chironomus dilutus (10-d exposure). Sediments were collected from seven test sites with mussel communities classified as impacted and in proximity to coal mining or gas extraction activities, and from five reference sites with mussel communities classified as not impacted and no or limited coal mining or gas extraction activities. Additional samples were collected from six test sites potentially with high concentrations of polycyclic aromatic hydrocarbons (PAHs) and from a test site contaminated by a coal ash spill. Mean survival, length, or biomass of one or more test species was reduced in 10 of 14 test samples (71%) from impacted areas relative to the response of organisms in the five reference samples. A higher proportion of samples was classified as toxic to mussels (63% for rainbow mussels, 50% for wavy-rayed lampmussels) compared with amphipods (38%) or midge (38%). Concentrations of total recoverable metals and total PAHs in sediments did not exceed effects-based probable effect concentrations (PECs). However, the survival, length, or biomasses of the mussels were reduced significantly with increasing PEC quotients for metals and for total PAHs, or with increasing sum equilibrium-partitioning sediment benchmark toxic units for PAHs. The growth of the rainbow mussel also significantly decreased with increasing concentrations of a major anion (chloride) and major cations (calcium and magnesium) in sediment pore water. Results of the present study indicated that (1) the findings from laboratory tests were generally consistent with the field observations of impacts on mussel populations; (2) total recoverable metals, PAHs, or major ions, or all three in sediments might have contributed to the sediment toxicity; (3) the mussels were more sensitive to the contaminants in sediments than the commonly tested amphipod and midge; and (4) a sediment toxicity benchmark of 1.0 based on PECs may not be protective of mussels.


Asunto(s)
Minas de Carbón , Sedimentos Geológicos/química , Gas Natural , Contaminantes Químicos del Agua/toxicidad , Anfípodos/fisiología , Animales , Chironomidae , Hidrocarburos Policíclicos Aromáticos/toxicidad , Tennessee , Pruebas de Toxicidad , Unionidae
5.
Environ Toxicol Chem ; 26(10): 2075-85, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17867877

RESUMEN

Water quality data were collected from three drainages supporting the endangered Carolina heelsplitter (Lasmigona decorata) and dwarf wedgemussel (Alasmidonta heterodon) to determine the potential for impaired water quality to limit the recovery of these freshwater mussels in North Carolina, USA. Total recoverable copper, total residual chlorine, and total ammonia nitrogen were measured every two months for approximately a year at sites bracketing wastewater sources and mussel habitat. These data and state monitoring datasets were compared with ecological screening values, including estimates of chemical concentrations likely to be protective of mussels, and federal ambient water quality criteria to assess site risks following a hazard quotient approach. In one drainage, the site-specific ammonia ecological screening value for acute exposures was exceeded in 6% of the samples, and 15% of samples exceeded the chronic ecological screening value; however, ammonia concentrations were generally below levels of concern in other drainages. In all drainages, copper concentrations were higher than ecological screening values most frequently (exceeding the ecological screening values for acute exposures in 65-94% of the samples). Chlorine concentrations exceeding the acute water quality criterion were observed in 14 and 35% of samples in two of three drainages. The ecological screening values were exceeded most frequently in Goose Creek and the Upper Tar River drainages; concentrations rarely exceeded ecological screening values in the Swift Creek drainage except for copper. The site-specific risk assessment approach provides valuable information (including site-specific risk estimates and ecological screening values for protection) that can be applied through regulatory and nonregulatory means to improve water quality for mussels where risks are indicated and pollutant threats persist.


Asunto(s)
Contaminantes Químicos del Agua/toxicidad , Animales , Bivalvos , Ecología , Exposición a Riesgos Ambientales , Agua Dulce , North Carolina , Medición de Riesgo
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