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1.
JSES Int ; 8(2): 268-273, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38464449

RESUMEN

Background: Accurate measurement of glenoid bone loss (GBL) is critical to preoperative planning in cases of recurrent shoulder instability. The concept of critical bone loss has been established with a value of GBL >13.5% being associated with higher failure rate following arthroscopic Bankart Repair. Advanced imaging, such as magnetic resonance imaging (MRI) scans, can be used to quantify GBL prior to surgery using the best-fit circle technique. Surgeons have traditionally relied on visual inspection of the MRI scan preoperatively or on visual inspection of the glenoid at the time of arthroscopy to determine whether GBL is present. The purpose of this study is to determine if 3 fellowship-trained shoulder surgeons could adequately quantify GBL without using best-fit circle measurements on MRI. Methods: A retrospective review was performed which included 122 patients over an 8-year period that had an arthroscopic Bankart repair performed by 3 fellowship-trained surgeons. In all patients, preoperative MRI scans were retrospectively measured using best-fit circle technique to determine true GBL and compare that to the surgeons' preoperative and intraoperative estimation of GBL. Results: GBL was correctly identified in only 36% (18/50) of patients when the preoperative best-fit circle measurements were not made. Critical bone loss was missed in 9.8% (12/122) of patients in the study group. The estimated mean bone loss in that group by visual inspection was 11.3% compared to 16% true bone loss measured on MRI. Even in the 18 patients with some identified bone loss prior to surgery, critical bone loss was missed in 6 patients when using visual inspection of the MRI or intraoperative inspection alone. Conclusion: Simple visual inspection of glenoid images on MRI scan and visual inspection of the glenoid at the time of surgery are inaccurate in determining the true extent of GBL especially in cases of subtle bone deficiency. Preoperative planning is dependent on the exact degree of bone deficiency and measurement on the MRI scan using the best-fit circle technique is recommended in all cases of instability surgery.

2.
Artículo en Inglés | MEDLINE | ID: mdl-30701257

RESUMEN

Verticillium nonalfalfae, a cosmopolitan soil-borne phytopathogen, causes vascular wilt in agricultural crops and perennial woody plants. Select strains of V. nonalfalfae can cause lethal disease in the invasive tree Ailanthus altissima and several have since been utilized as a biological control (biocontrol) against this widespread invader. Here, we report the genome sequence and annotation of V. nonalfalfae strain VnAa140/NRRL 66861.

3.
J Environ Qual ; 42(2): 305-11, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23673822

RESUMEN

We monitored spatial and temporal patterns of total Hg in forest bioindicators to assess possible local, regional, and global changes in atmospheric Hg deposition. Total Hg concentrations were monitored in leaves and fresh litterfall of northern red oak ( L.), on an epiphytic moss ( Hedw.) on northern red oak stems, and in surface soil organic matter (O and O horizons) in Pennsylvania oak-dominated forests. Variously configured plots were used to monitor Hg deposition near local coal-fired generating stations and an industrial city and along an extended regional transect. Linearly decreasing temporal trends in Hg concentrations occurred in leaves, litterfall, moss, and soil O and O. Mean annual Hg concentrations were often greater near local emissions sources compared with remote areas, especially in the initial monitoring period. Decreasing time trends for different impact areas tended to converge due to greater rates of Hg decrease where initial bioindicator Hg levels were higher. Fresh litter and soil O showed the greatest overall potential as Hg bioindicators. We conclude that Hg deposition has been significantly decreasing over time throughout the study area as a result of locally and regionally declining Hg emissions. Reductions in Hg emissions are likely a co-benefit of the 1990 Clean Air Act regulations and changing industrial activities. Recent leveling of several bioindicator Hg time trends may foretell a shift in Hg depositional patterns. Mercury monitoring studies such as this fulfill a need for documenting local and regional effects of emissions reduction.


Asunto(s)
Mercurio , Contaminantes del Suelo , Contaminantes Atmosféricos , Monitoreo del Ambiente , Bosques , Pennsylvania , Suelo
4.
Fungal Genet Biol ; 56: 147-57, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23608321

RESUMEN

Ambrosia beetle fungiculture represents one of the most ecologically and evolutionarily successful symbioses, as evidenced by the 11 independent origins and 3500 species of ambrosia beetles. Here we document the evolution of a clade within Fusarium associated with ambrosia beetles in the genus Euwallacea (Coleoptera: Scolytinae). Ambrosia Fusarium Clade (AFC) symbionts are unusual in that some are plant pathogens that cause significant damage in naïve natural and cultivated ecosystems, and currently threaten avocado production in the United States, Israel and Australia. Most AFC fusaria produce unusual clavate macroconidia that serve as a putative food source for their insect mutualists. AFC symbionts were abundant in the heads of four Euwallacea spp., which suggests that they are transported within and from the natal gallery in mandibular mycangia. In a four-locus phylogenetic analysis, the AFC was resolved in a strongly supported monophyletic group within the previously described Clade 3 of the Fusarium solani species complex (FSSC). Divergence-time estimates place the origin of the AFC in the early Miocene ∼21.2 Mya, which coincides with the hypothesized adaptive radiation of the Xyleborini. Two strongly supported clades within the AFC (Clades A and B) were identified that include nine species lineages associated with ambrosia beetles, eight with Euwallacea spp. and one reportedly with Xyleborus ferrugineus, and two lineages with no known beetle association. More derived lineages within the AFC showed fixation of the clavate (club-shaped) macroconidial trait, while basal lineages showed a mix of clavate and more typical fusiform macroconidia. AFC lineages consisted mostly of genetically identical individuals associated with specific insect hosts in defined geographic locations, with at least three interspecific hybridization events inferred based on discordant placement in individual gene genealogies and detection of recombinant loci. Overall, these data are consistent with a strong evolutionary trend toward obligate symbiosis coupled with secondary contact and interspecific hybridization.


Asunto(s)
Fusarium/clasificación , Fusarium/aislamiento & purificación , Variación Genética , Persea/parasitología , Simbiosis , Gorgojos/microbiología , Estructuras Animales/microbiología , Animales , Análisis por Conglomerados , ADN de Hongos/química , ADN de Hongos/genética , ADN Ribosómico/química , ADN Ribosómico/genética , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/genética , Fusarium/genética , Fusarium/fisiología , Genes de ARNr , Datos de Secuencia Molecular , Factor 1 de Elongación Peptídica/genética , Filogenia , ARN Polimerasa II/genética , ARN de Hongos/genética , ARN Ribosómico/genética , Análisis de Secuencia de ADN , Gorgojos/crecimiento & desarrollo
5.
Am Psychol ; 65(3): 171-81, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20350016

RESUMEN

This article describes the challenges that women and women of color face in their quest to achieve and perform in leadership roles in work settings. We discuss the barriers that women encounter and specifically address the dimensions of gender and race and their impact on leadership. We identify the factors associated with gender evaluations of leaders and the stereotypes and other challenges faced by White women and women of color. We use ideas concerning identity and the intersection of multiple identities to understand the way in which gender mediates and shapes the experience of women in the workplace. We conclude with suggestions for research and theory development that may more fully capture the complex experience of women who serve as leaders.


Asunto(s)
Liderazgo , Grupos de Población , Prejuicio , Estereotipo , Movilidad Laboral , Femenino , Humanos , Autoimagen , Identificación Social , Percepción Social
6.
Plant Dis ; 93(11): 1158-1162, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30754572

RESUMEN

Verticillium albo-atrum causes unprecedented wilt and mortality of the invasive tree-of-heaven (Ailanthus altissima) within forests of south-central Pennsylvania. Stem inoculation of potted Ailanthus seedlings in the greenhouse and canopy Ailanthus trees in the field with V. albo-atrum resulted in 100% mortality. Stem inoculation of understory striped maple saplings in the field also resulted in 100% mortality. However, the high susceptibility of striped maple was not observed in naturally infected stands, where only 1% of striped maple saplings exhibited Verticillium wilt. Inoculation of chestnut oak, northern red oak, red maple, sugar maple, white ash, and yellow-poplar seedlings or canopy trees with V. albo-atrum did not induce wilt symptoms. Non-Ailanthus tree species growing adjacent to dead and dying Ailanthus trees in the field were asymptomatic. Pending further studies, V. albo-atrum should be considered as a potential biocontrol agent for invasive Ailanthus.

7.
Plant Dis ; 93(7): 747-751, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30764366

RESUMEN

Extensive, unprecedented wilt and mortality of the highly invasive tree-of-heaven (Ailanthus altissima) occurred recently within mixed-hardwood forests in south-central Pennsylvania. Until this study, the cause of the epidemic was unknown. Verticillium albo-atrum was consistently isolated from symptomatic Ailanthus seedlings and trees in areas having high levels of mortality, whereas V. dahliae was isolated from small scattered patches of diseased Ailanthus. Inoculations of potted Ailanthus seedlings in the greenhouse, as well as canopy trees in the field, revealed that both V. albo-atrum and V. dahliae were capable of infecting Ailanthus, but V. albo-atrum was more pathogenic. All Ailanthus seedlings and canopy trees inoculated with V. albo-atrum died within 3 months. In contrast, Ailanthus seedlings and canopy trees inoculated with V. dahliae became symptomatic, but 84% were still living 1 year following inoculation. We conclude that the major cause of Ailanthus wilt within forests of south-central Pennsylvania is V. albo-atrum. Pending further studies, including risk analysis, V. albo-atrum may be considered as a possible biocontrol agent for invasive Ailanthus.

8.
Environ Pollut ; 143(3): 555-64, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16458398

RESUMEN

During 1993-1996 and 2001-2003, we evaluated the percentage of plants (incidence) exhibiting ozone-induced foliar symptoms on vegetation within a National Wildlife Refuge located along the Atlantic Ocean coast of New Jersey, USA. Incidence varied among plant species and years. Bioindicator plants most sensitive to ozone, across all years, included native common milkweed (Asclepias syriaca) and wild grape (Vitis spp.), as well as introduced tree-of-heaven (Ailanthus altissima). Less sensitive bioindicators included Virginia creeper (Parthenocissus quinquefolia) and winged sumac (Rhus coppolina). Black cherry (Prunus serotina) and sassafras (Sassafras albidum) were least sensitive. The greatest incidence of ozone symptoms, across all plant species, occurred in 1996, followed by 2001>1995>1994>1993>2003>2002. A model was developed that showed a statistically significant relationship between incidence of ozone symptoms and the following parameters: plant species, Palmer Drought Severity Index, and the interaction of W126 x N100 measures of ambient ozone.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Monitoreo del Ambiente/métodos , Modelos Teóricos , Ozono/efectos adversos , Enfermedades de las Plantas/estadística & datos numéricos , Plantas , Contaminantes Atmosféricos/análisis , Biomarcadores , Monitoreo Epidemiológico , Humanos , Incidencia , New Jersey/epidemiología , Ozono/análisis , Enfermedades de las Plantas/etiología , Estaciones del Año , Árboles
9.
Mol Phylogenet Evol ; 35(2): 313-22, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15804406

RESUMEN

Phylogenetic analyses of 27 artillery fungus (Sphaerobolus sp.) isolates were conducted to identify species boundaries in the genus Sphaerobolus. Multiple gene genealogies inferred from maximum likelihood, Bayesian, and maximum-parsimony analyses of sequence data from individual loci (mtSSU, ITS, EF 1-alpha, and LSU) and a combined dataset (mtSSU, ITS, and EF 1-alpha) concordantly indicate the existence of three deeply divergent lineages in the genus Sphaerobolus, each representing a phylogenetic species. These three phylogenetic species correspond to two known species: Sphaerobolus iowensis and Sphaerobolus stellatus, and a newly discovered species. Suprageneric phylogenetic analyses of the mtSSU and LSU datasets containing representatives of related genera of the gomphoid-phalloid clade of Homobasidiomycetes suggested that the undescribed taxon likely is more closely related to S. stellatus than to S. iowensis.


Asunto(s)
Basidiomycota/clasificación , Basidiomycota/genética , Filogenia , Polimorfismo Genético , Secuencia de Bases , Basidiomycota/aislamiento & purificación , ADN de Hongos/genética , Variación Genética , Geografía , Reacción en Cadena de la Polimerasa , Estados Unidos
10.
Mycologia ; 97(3): 680-94, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16392256

RESUMEN

Despite mycologists' interest in its unique spore-dispersal mechanism, systematic studies of the genus Sphaerobolus have received little attention. In our previous work multiple gene genealogies indicated the existence of three divergent lineages in the genus Sphaerobolus, each representing a phylogenetic species. Macro- and micromorphological analyses of colony and fruit-body characters presented here confirmed that these three phylogenetic species correspond to two known species, S. iowensis and S. stellatus, and a newly discovered species. In addition, an expanded gene genealogical analysis is presented for the three species. The new species, named Sphaerobolus ingoldii Geml, Davis et Geiser, is described based on both molecular and morphological data. In addition, while S. iowensis previously had been reported in only two localities, we found that it is as common as or more common than S. stellatus in North America. Despite the considerable amount of DNA polymorhism found in all species, nested clade analyses of S. iowensis and S. stellatus indicated little phylogeographic structure in either species, perhaps due to heavy movement mediated by human activities.


Asunto(s)
Basidiomycota/clasificación , Basidiomycota/citología , Basidiomycota/genética , Basidiomycota/crecimiento & desarrollo , ADN de Hongos/química , ADN de Hongos/genética , ADN Mitocondrial/química , ADN Mitocondrial/genética , ADN Ribosómico/química , ADN Ribosómico/genética , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/genética , Microbiología Ambiental , Geografía , Microscopía , Datos de Secuencia Molecular , Factor 1 de Elongación Peptídica/genética , Filogenia , ARN Ribosómico 28S/genética , Análisis de Secuencia de ADN , Homología de Secuencia , Esporas Fúngicas/citología , Estados Unidos
11.
Environ Pollut ; 120(3): 701-5, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12442793

RESUMEN

Spartina alterniflora plants were collected from salt marshes within New Jersey, South Carolina, and Georgia USA and shipped to The Pennsylvania State University. New plants were grown from rhizomes in six open-top field chambers. Three chambers received charcoal-filtered air, and three received charcoal-filtered air plus 80 ppb ozone, 8 h/day for 65 days. Flower, leaf, and shoot number per plant were recorded weekly. Photosynthetic rates were measured in week 5, and foliar injury was assessed during week 9. Final dry weight of roots, shoots, and rhizomes were determined. While ozone-treated plants from all states expressed symptoms of ozone injury, plants from South Carolina exhibited no effect of ozone on any other measured variable. Plants from the Georgia site showed ozone-induced reductions in all measured variables except leaf dry weight. Ozone-treated plants from New Jersey showed reductions in photosynthetic rate, leaf and shoot number, and root dry weights. Only plants from New Jersey produced flowers, with ozone treatment causing delay in flowering and reduction in the number of flower spikes produced.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Ozono/efectos adversos , Poaceae/crecimiento & desarrollo , Agua de Mar , Factores de Tiempo , Pruebas de Toxicidad
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