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1.
Ecology ; 96(7): 1761-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26378298

RESUMO

Habitat loss worldwide has led to the widespread use of restoration practices for the recovery of imperiled species. However, recovery success may be hampered by focusing on plant communities, rather than the complex suite of direct and indirect interactions among trophic levels that occur in natural systems. Through a factorial field experiment, we tested the effects of wetland restoration on egg and juvenile survival of a locally rare butterfly, Satyrodes appalachia, via tree removal and damming. Tree removal more than tripled S. appalachia host plant abundance, but neither restoration action directly affected S. appalachia egg and juvenile survival. Instead, we found strong indirect effects of habitat manipulation on S. appalachia egg and juvenile survival that were mediated through predation. The interaction of tree removal and damming significantly decreased predation of S. appalachia eggs relative to each treatment alone. Damming alone had a significant positive indirect effect on the survival of S. appalachia juveniles, likely because increases in standing water reduced predator access. Our results emphasize the need for experiments that evaluate the demographic responses of imperiled species to habitat restoration prior to management action and quantify potential indirect effects mediated through higher trophic levels.


Assuntos
Borboletas/classificação , Borboletas/crescimento & desenvolvimento , Recuperação e Remediação Ambiental , Áreas Alagadas , Animais , Monitoramento Ambiental , Larva/fisiologia , Óvulo , Comportamento Predatório
2.
Ecol Lett ; 2(5): 286-293, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33810630

RESUMO

Declining biodiversity represents one of the most dramatic and irreversible aspects of anthropogenic global change, yet the ecological implications of this change are poorly understood. Recent studies have shown that biodiversity loss of basal species, such as autotrophs or plants, affects fundamental ecosystem processes such as nutrient dynamics and autotrophic production. Ecological theory predicts that changes induced by the loss of biodiversity at the base of an ecosystem should impact the entire system. Here we show that experimental reductions in grassland plant richness increase ecosystem vulnerability to invasions by plant species, enhance the spread of plant fungal diseases, and alter the richness and structure of insect communities. These results suggest that the loss of basal species may have profound effects on the integrity and functioning of ecosystems.

3.
Am Nat ; 158(1): 17-35, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18707312

RESUMO

We experimentally separated the effects of two components of plant diversity-plant species richness and plant functional group richness-on insect communities. Plant species richness and plant functional group richness had contrasting effects on insect abundances, a result we attributed to three factors. First, lower insect abundances at higher plant functional group richness were explained by a sampling effect, which was caused by the increasing likelihood that one low-quality group, C4 grasses, would be present and reduce average insect abundances by 25%. Second, plant biomass, which was positively related to plant functional group richness, had a strong, positive effect on insect abundances. Third, a positive effect of plant species richness on insect abundances may have been caused by greater availability of alternate plant resources or greater vegetational structure. In addition, a greater diversity of insect species, whose individual abundances were often unaffected by changes in plant species richness, may have generated higher total community abundances. After controlling for the strong, positive influence of insect abundance on insect diversity through rarefaction, insect species richness increased as plant species richness and plant functional group richness increased. Although these variables did not explain a high proportion of variation individually, plant species richness and plant functional group richness had similar effects on insect diversity and opposing effects on insect abundances, and both factors may explain how the loss of plant diversity influences higher trophic levels.

4.
J Med Liban ; 42(4): 240-1, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8558586

RESUMO

The evolving world of facial plastic and reconstructive surgery has, as in any other specialty or subspecialty, seen new trends and experienced tremendous bounds. In this review they will be discussed under two headings: cosmetic surgery and reconstructive surgery. The aim of this paper is to help educate the nonspecialist about the most significant recent advances.


Assuntos
Face/cirurgia , Cirurgia Plástica , Estética , Humanos , Cirurgia Plástica/métodos , Cirurgia Plástica/tendências
5.
J Fr Ophtalmol ; 36(1): 82-6, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23219507

RESUMO

We report a case of traumatic partial flap dislocation 10 years after uneventful laser in situ keratomileusis (LASIK). The patient was treated bilaterally for hyperopia and astigmatism with LASIK. A superior-hinged corneal flap was created using the Moria M2 microkeratome (Moria SA, Antony, France) and the surgery was uneventful. Ten years later, partial flap dislocation was diagnosed after mild trauma. This case suggests that flap dislocations can occur during recreational activities up to 10 years after surgery. Full visual recovery is achievable if the case is managed promptly. Further studies should evaluate the potential protective role of an inferior hinge during LASIK.


Assuntos
Traumatismos Oculares/etiologia , Traumatismos Oculares/cirurgia , Ceratomileuse Assistida por Excimer Laser In Situ/efeitos adversos , Retalhos Cirúrgicos/efeitos adversos , Acidentes , Adulto , Astigmatismo/cirurgia , Humanos , Hiperopia/cirurgia , Masculino , Recreação , Fatores de Tempo
6.
Mol Syndromol ; 1(4): 169-175, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21373256

RESUMO

Waardenburg syndrome (WS) is a genetic disorder characterized primarily by depigmentation of the skin and hair, heterochromia of the irides, sensorineural deafness, and sometimes by dystopia canthorum, and Hirschsprung disease. WS presents a large clinical and genetic heterogeneity. Four different types have been individualized and linked to 5 different genes. We report 2 cases of WS type II and 1 case of WS type IV from Lebanon and Syria. The genetic studies revealed 2 novel mutations in the MITF gene of the WS type II cases and 1 novel homozygous mutation in the EDNRB gene of the WS type IV case. This is the first molecular study of patients from the Arab world. Additional cases will enable a more detailed description of the clinical spectrum of Waardenburg syndrome in this region.

9.
Proc Natl Acad Sci U S A ; 90(2): 592-4, 1993 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-11607351

RESUMO

Species in a Colorado subalpine ecosystem show subtle interdependences. Red-naped sapsuckers play two distinct keystone roles. They excavate nest cavities in fungus-infected aspens that are required as nest sites by two species of swallows, and they drill sap wells into willows that provide abundant nourishment for themselves, hummingbirds, orange-crowned warblers, chipmunks, and an array of other sap robbers. The swallows thus depend on, and the sap robbers benefit from, a keystone species complex comprised of sapsuckers, willows, aspens, and a heartwood fungus. Disappearance of any element of the complex could cause an unanticipated unraveling of the community.

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