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2.
Environ Manage ; 60(3): 513-525, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28516312

RESUMO

The widespread degradation of lotic ecosystems has prompted extensive river restoration efforts globally, but many studies have reported modest ecological responses to rehabilitation practices. The functional properties of biotic communities are rarely examined within post-project appraisals, which would provide more ecological information underpinning ecosystem responses to restoration practices and potentially pinpoint project limitations. This study examines macroinvertebrate community responses to three projects which aimed to physically restore channel morphologies. Taxonomic and functional trait compositions supported by widely occurring lotic habitats (biotopes) were examined across paired restored and non-restored (control) reaches. The multivariate location (average community composition) of taxonomic and functional trait compositions differed marginally between control and restored reaches. However, changes in the amount of multivariate dispersion were more robust and indicated greater ecological heterogeneity within restored reaches, particularly when considering functional trait compositions. Organic biotopes (macrophyte stands and macroalgae) occurred widely across all study sites and supported a high alpha (within-habitat) taxonomic diversity compared to mineralogical biotopes (sand and gravel patches), which were characteristic of restored reaches. However, mineralogical biotopes possessed a higher beta (between-habitat) functional diversity, although this was less pronounced for taxonomic compositions. This study demonstrates that examining the functional and structural properties of taxa across distinct biotopes can provide a greater understanding of biotic responses to river restoration works. Such information could be used to better understand the ecological implications of rehabilitation practices and guide more effective management strategies.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Recuperação e Remediação Ambiental , Invertebrados/classificação , Rios/química , Animais , Ecologia , Fenótipo , Reino Unido
3.
Environ Entomol ; 44(4): 1011-21, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26314046

RESUMO

Nonmanaged plants occurring along forest edges and in suburban settings were sampled for brown marmorated stink bug, Halyomorpha halys (Stål), in North Carolina (NC) and Virginia (VA) over the course of three growing seasons. Commercial soybeans (Glycine max), an attractive cultivated host, were also sampled in 2014 in NC and in VA from 2010-2014. Very few H. halys were found on nonmanaged plants or soybean fields in the coastal plain region of either state, but substantial populations were recorded in the piedmont and mountain regions. From 2011 to 2013, H. halys comprised from 51 to 97% of all stink bug species observed on nonmanaged plants in the piedmont and mountain regions. In VA, the distribution expanded from detection in 12 counties in 2010 to 53 counties in 2014, with economically damaging levels occurring in the piedmont region. During these studies, H. halys were observed to complete one and a partial second generation per year in western NC and southwestern VA, similar to that previously observed in regions farther north. Several plants were identified as preferred hosts, with tree of heaven, catalpa, yellowwood, paulownia, cherry, walnut, redbud, and grape having consistently high numbers of H. halys. Knowing that these plants are preferred by H. halys during certain stages of the insects' development will aid in the search for H. halys in new areas, as well as serve as one predictor of the likelihood of a certain area to attract and sustain large H. halys populations.


Assuntos
Florestas , Glycine max/crescimento & desenvolvimento , Heterópteros/fisiologia , Agricultura , Animais , Heterópteros/crescimento & desenvolvimento , North Carolina , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia , Óvulo/crescimento & desenvolvimento , Óvulo/fisiologia , Dinâmica Populacional , Estações do Ano , Virginia
4.
Environ Entomol ; 41(3): 612-20, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22732620

RESUMO

Bell pepper plots intercropped with flowering plants were measured for improving biological control provided by natural enemies of the European corn borer [Ostrinia nubilalis (Hübner)]. The intercropped plants Dill, Anethum graveolens L.; coriander, Coriandrum sativum L.; and buckwheat, Fagopyrum escuelentum Moench; were established on the edge of two pepper plots and compared with nonintercropped control plots. Predation by the three species Orius insidiosus Say; Coleomegilla maculata DeGeer; and Chrysoperla, sp. Stephens, was monitored by installing O. nubilalis egg masses on sentinel plants in 2008, 2009, and 2010. To assess negative impacts of alternative prey on O. nubilalis egg predation, green peach aphid, Myzus persicae (Sulzer) populations were monitored via whole-plant counts in 2009 and 2010. Myzus persicae densities on pepper plants peaked in June or July and then declined rapidly. Predation on O. nubilalis eggs increased rapidly after aphid populations declined. Aphid populations were reduced in two out of three field-seasons in intercropped plots. Seasonal predation by O. insidiosus was significantly higher in the intercropped system four out of five field-seasons and one field season by C. maculata. Results indicate that biocontrol of O. nubilalis can be improved by intercropping with flowering plants, although this capacity may depend on the abundance of alternative prey.


Assuntos
Insetos/fisiologia , Mariposas/fisiologia , Controle Biológico de Vetores/métodos , Comportamento Predatório , Anethum graveolens , Animais , Afídeos/fisiologia , Capsicum , Besouros/fisiologia , Coriandrum , Produtos Agrícolas , Fagopyrum , Cadeia Alimentar , Heterópteros/fisiologia , Larva/fisiologia , New Jersey , Óvulo/fisiologia , Densidade Demográfica , Estações do Ano , Especificidade da Espécie
5.
J Contin Educ Nurs ; 27(2): 85-8, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8698932

RESUMO

Staff nurses experience time demands that frequently prevent them from attending inservice offerings. The 12 1/2 minute learning session is an innovative approach designed to meet the learning needs of the psychiatric nursing staff in spite of time constraints. The guiding principles for these sessions are: 1) "We learn what we care about," 2) preparation for sessions conveys commitment, and 3) accountability for learning is the individual's responsibility but opportunities for learning are shared. Identified outcomes of these groups are the "earthquake effect" or the shifting of one's footing; opportunity for effective debunking or uncovering of habitual patterns; and "bushfire effect" or contagiousness of enthusiasm.


Assuntos
Educação Continuada em Enfermagem/métodos , Enfermagem Psiquiátrica/educação , Ensino/métodos , Humanos , Aprendizagem , Fatores de Tempo
6.
Am J Physiol ; 238(1): H87-92, 1980 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7356037

RESUMO

Pinane thromboxane A2 (PTA2), a thromboxane A2 analog has been shown to antagonize the vasoconstriction and platelet aggregation induced by thromboxane A2, in addition to specifically inhibiting thromboxane synthetase. Because thromboxane A2 generation would be detrimental in acute myocardial ischemia (MI) by both decreasing coronary blood flow and increasing platelet aggregation, inhibition of thromboxane production and action may be beneficial in myocardial ischemia. In pentobarbital-anesthetized cats, the left anterior descending coronary artery was ligated, and PTA2 (0.5 mumol . kg-1 . h-1) or a Na2CO3 vehicle was infused 30 min post-MI for 270 min. Compared to vehicle-treated MI cats, PTA2 prevented the increase in plasma thromboxane levels seen at 2 through 5 h (P less than 0.005 at 2 through 5 h) and prevented the large increase in plasma CK activities at 4 and 5 h (P less than 0.025). In addition, PTA2 treatment abolished the differences in myocardial CK activities between ischemic and nonischemic regions and prevented the decrease in percent-bound cathepsin D in the ischemic region. Moreover, ECG analysis revealed a decreased incidence of premature beats in PTA2-treated MI cats as compared to MI-vehicle cats. In summary, these data indicate that PTA2 protects the ischemic myocardium and provide further evidence that inhibition of thromboxane formation, in addition to antagonism of its activity, is beneficial during the early stages of acute myocardial ischemia.


Assuntos
Doença das Coronárias/fisiopatologia , Coração/fisiopatologia , Tromboxano A2/farmacologia , Tromboxanos/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Catepsinas/sangue , Gatos , Doença das Coronárias/sangue , Creatina Quinase/sangue , Eletrocardiografia , Frequência Cardíaca/efeitos dos fármacos , Masculino , Tromboxano B2/sangue
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