Publications by authors named "Souther S"

As disturbance regimes change in response to anthropogenic activities, ecosystem resilience is critically important to the persistence of biodiversity and ecological functions. However, resilience in literature is often treated as an abstract concept, with widely varying definitions. Achieving common and reliable resilience metrics that cross systems and contexts remains elusive.

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Pollinator losses threaten ecosystems and food security, diminishing gene flow and reproductive output for ecological communities and impacting ecosystem services broadly. For four focal families of bees and butterflies, we constructed over 1400 ensemble species distribution models over two time periods for North America. Models indicated disproportionally increased richness in eastern North America over time, with decreases in richness over time in the western US and southern Mexico.

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Disturbance is one of the fundamental shapers of ecological communities, redistributing resources and resetting successional pathways. Human activities including resources management can influence disturbance regimes and trajectories by actively imposing or suppressing disturbance events or shaping ecosystem recovery via disturbance response. Furthermore, different management objectives may drive different disturbance responses.

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Resilience quantifies the ability of a system to remain in or return to its current state following disturbance. Due to inconsistent terminology and usage of resilience frameworks, quantitative resilience studies are challenging, and resilience is often treated as an abstract concept rather than a measurable system characteristic. We used a novel, spatially explicit stakeholder engagement process to quantify social-ecological resilience to fire, in light of modeled social-ecological fire risk, across the non-fire-adapted Sonoran Desert Ecosystem in Arizona, USA.

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As a multi-jurisdictional, non-fire-adapted region, the Sonoran Desert Ecoregion is a complex, social-ecological system faced increasingly with no-analogue conditions. A diversity of management objectives and activities form the socioecological landscape of fire management. Different managers have different objectives, resources, and constraints, and each therefore applies different activities.

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Grasslands managed for grazing are the largest land-use category globally, with a significant proportion of these grasslands occurring in semiarid and arid regions. In such dryland systems, the effect of grazing on native plant diversity has been equivocal, some studies suggesting that grazing reduces native plant diversity, others that grazing increases or has little impact on diversity. One impediment toward generalizing grazing effects on diversity in this region is that high levels of interannual variation in precipitation may obfuscate vegetative response patterns.

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This case documents a rare set of congenital anomalies that resulted in an atypical cystic lesion in the cranial vagina of a queen. A discrete cystic lesion was identified in an 8 year old intact female domestic shorthair cat presenting for routine ovariohysterectomy. Morphological, radiographic, and histopathological findings were consistent with segmental aplasia of the uterus, cervix, and vagina resulting in a blind dilation of the cranial vagina.

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Plants are often genetically specialized as ecotypes attuned to local environmental conditions. When conditions change, the optimal environment may be physically displaced from the local population, unless dispersal or in situ evolution keep pace, resulting in a phenomenon called adaptational lag. Using a 30-year-old reciprocal transplant study across a 475 km latitudinal gradient, we tested the adaptational lag hypothesis by measuring both short-term (tiller population growth rates) and long-term (17-year survival) fitness components of Eriophorum vaginatum ecotypes in Alaska, where climate change may have already displaced the optimum.

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Article Synopsis
  • The BCG vaccine strain is being used to create stable recombinant vaccines expressing HIV and SIV antigens, which is significant due to its established safety profile.
  • A method involving leucine auxotrophic complementation was developed to ensure the consistent expression and stability of these recombinant strains.
  • Quality control measures confirmed the stability and efficiency of antigen production, leading to successful immune responses in mice, thus increasing confidence in the vaccine's potential for use in immunogenicity studies.
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Over the next century, the conservation of biodiversity will depend not only on our ability to understand the effect of climate change, but also on our capacity to predict how other factors interact with climate change to influence species viability. We used American ginseng (Panax quinquefolius L.), the United States' premier wild-harvested medicinal, as a model system to ask whether the effect of harvest on extinction risk depends on changing climatic conditions.

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Conservation practitioners and scientists are often faced with seemingly intractable problems in which traditional approaches fail. While other sectors (e.g.

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American ginseng (Panax quinquefolius L.) is an uncommon to rare understory plant of the eastern deciduous forest. Harvesting to supply the Asian traditional medicine market made ginseng North America's most harvested wild plant for two centuries, eventually prompting a listing on CITES Appendix II.

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Background And Aims: Local climatic adaptation can influence species' response to climate change. If populations within a species are adapted to local climate, directional change away from mean climatic conditions may negatively affect fitness of populations throughout the species' range.

Methods: Adaptive differentiation to temperature was tested for in American ginseng (Panax quinquefolius) by reciprocally transplanting individuals from two populations, originating at different elevations, among temperature treatments in a controlled growth chamber environment.

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Bioclimatic envelope models of species' responses to climate change are used to predict how species will respond to increasing temperatures. These models are frequently based on the assumption that the northern and southern boundaries of a species' range define its thermal niche. However, this assumption may be violated if populations are adapted to local temperature regimes and have evolved population-specific thermal optima.

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Purpose: To demonstrate that bioengineered Apligraf improves time to wound healing in sternal and leg wound complications after coronary artery bypass surgery.

Description: Between 1998 and 2001, 1,550 patients underwent coronary artery bypass surgery utilizing saphenous vein. In 45 (2.

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Background: Rupture of the aorta is a major cause of death after motor vehicle accidents. Survival depends on early diagnosis, and emergency aortography is the standard imaging method. Although transesophageal echocardiography is noninvasive and can provide high-resolution images of the aorta, information about its value in patients with trauma is limited.

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Midventricular obstruction is an uncommon finding previously defined by catheterization and angiographic techniques in patients with hypertrophic cardiomyopathy. This study describes the clinical and echocardiographic findings of 10 consecutive patients (mean age 73 years) with severe concentric left ventricular (LV) hypertrophy and the unusual finding of a dynamic systolic obstruction located in the midportion of the left ventricle. All patients were known to have chronic hypertension, and none had a history or family history of hypertrophic cardiomyopathy.

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Our current principles for the treatment of anterior neck deformities originally evolved from cadaver dissections and clinical observations. These principles have been applied over the past seven years in nearly 100 patients. We combine as indicated submandibular lipectomy, excision of the submental fat pad, chin implantation, creation or tightening of the platysma muscular sling, and skin tightening and resection.

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The platysma muscle has become recognized as a key to the correction of deformities of the neck. We believe that the decussation of the medial fibers of the platysma muscle is critical to the support of the submental region and is a factor in the pleasing angle between the neck and the chin. The approximation of the medial borders of the platysma has been described in combination with other direct approaches to the anterior neck or with aggressive repositioning or flaps of the platysma.

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An area of skin loss on the weight-bearing area of the sole of the foot was successfully reconstructed with a split-thickness skin graft taken from the non-weight bearing area of the sole. Excessive callus formation adjacent to the graft was not noted, and the donor site is convenient and concealed. Grafts up to 6 x 10 cm may be taken from the average adult foot.

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A quick, simple, and reliable operation for the correction of mild to moderate ptosis in the presence of fair to good levator function was described by Fasanella and Servat nearly two decades ago. This operation consists of resection of the conjunctiva, tarsus, and müller's muscle using a conjunctival approach. We have performed this operation in 39 patients with good to excellent results in 38.

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The use of fluorescein as a predictor of skin viability in the rat flap model of avascular skin necrosis is well known in the field of plastic surgery. Inherent in this model are several faults that must be corrected if it is to become a valid standard. Fluorescence readings are one of the main variables in flap models.

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