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Search Results: 1 - 10 of 332817 matches for " Michael J. Lannoo "
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Seasonal Pattern of Batrachochytrium dendrobatidis Infection and Mortality in Lithobates areolatus: Affirmation of Vredenburg's “10,000 Zoospore Rule”
Vanessa C. Kinney,Jennifer L. Heemeyer,Allan P. Pessier,Michael J. Lannoo
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0016708
Abstract: To fully comprehend chytridiomycosis, the amphibian disease caused by the chytrid fungus Batrachochytrium dendrobatidis (Bd), it is essential to understand how Bd affects amphibians throughout their remarkable range of life histories. Crawfish Frogs (Lithobates areolatus) are a typical North American pond-breeding species that forms explosive spring breeding aggregations in seasonal and semipermanent wetlands. But unlike most species, when not breeding Crawfish Frogs usually live singly—in nearly total isolation from conspecifics—and obligately in burrows dug by crayfish. Crayfish burrows penetrate the water table, and therefore offer Crawfish Frogs a second, permanent aquatic habitat when not breeding. Over the course of two years we sampled for the presence of Bd in Crawfish Frog adults. Sampling was conducted seasonally, as animals moved from post-winter emergence through breeding migrations, then back into upland burrow habitats. During our study, 53% of Crawfish Frog breeding adults tested positive for Bd in at least one sample; 27% entered breeding wetlands Bd positive; 46% exited wetlands Bd positive. Five emigrating Crawfish Frogs (12%) developed chytridiomycosis and died. In contrast, all 25 adult frogs sampled while occupying upland crayfish burrows during the summer tested Bd negative. One percent of postmetamorphic juveniles sampled were Bd positive. Zoospore equivalents/swab ranged from 0.8 to 24,436; five out of eight frogs with zoospore equivalents near or >10,000 are known to have died. In summary, Bd infection rates in Crawfish Frog populations ratchet up from near zero during the summer to over 25% following overwintering; rates then nearly double again during and just after breeding—when mortality occurs—before the infection wanes during the summer. Bd-negative postmetamorphic juveniles may not be exposed again to this pathogen until they take up residence in crayfish burrows, or until their first breeding, some years later.
Mine Spoil Prairies Expand Critical Habitat for Endangered and Threatened Amphibian and Reptile Species
Michael J. Lannoo,Vanessa C. Kinney,Jennifer L. Heemeyer,Nathan J. Engbrecht,Alisa L. Gallant,Robert W. Klaver
Diversity , 2009, DOI: 10.3390/d1020118
Abstract: Coal extraction has been occurring in the Midwestern United States for over a century. Despite the pre-mining history of the landscape as woodlands, spent surface coalfields are often reclaimed to grasslands. We assessed amphibian and reptile species on a large tract of coal spoil prairie and found 13 species of amphibians (nine frog and four salamander species) and 19 species of reptiles (one lizard, five turtle, and 13 snake species). Two state-endangered and three state species of special concern were documented. The amphibian diversity at our study site was comparable to the diversity found at a large restored prairie situated 175 km north, within the historic prairie peninsula.
Localized Hotspots Drive Continental Geography of Abnormal Amphibians on U.S. Wildlife Refuges
Mari K. Reeves, Kimberly A. Medley, Alfred E. Pinkney, Marcel Holyoak, Pieter T. J. Johnson, Michael J. Lannoo
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0077467
Abstract: Amphibians with missing, misshapen, and extra limbs have garnered public and scientific attention for two decades, yet the extent of the phenomenon remains poorly understood. Despite progress in identifying the causes of abnormalities in some regions, a lack of knowledge about their broader spatial distribution and temporal dynamics has hindered efforts to understand their implications for amphibian population declines and environmental quality. To address this data gap, we conducted a nationwide, 10-year assessment of 62,947 amphibians on U.S. National Wildlife Refuges. Analysis of a core dataset of 48,081 individuals revealed that consistent with expected background frequencies, an average of 2% were abnormal, but abnormalities exhibited marked spatial variation with a maximum prevalence of 40%. Variance partitioning analysis demonstrated that factors associated with space (rather than species or year sampled) captured 97% of the variation in abnormalities, and the amount of partitioned variance decreased with increasing spatial scale (from site to refuge to region). Consistent with this, abnormalities occurred in local to regional hotspots, clustering at scales of tens to hundreds of kilometers. We detected such hotspot clusters of high-abnormality sites in the Mississippi River Valley, California, and Alaska. Abnormality frequency was more variable within than outside of hotspot clusters. This is consistent with dynamic phenomena such as disturbance or natural enemies (pathogens or predators), whereas similarity of abnormality frequencies at scales of tens to hundreds of kilometers suggests involvement of factors that are spatially consistent at a regional scale. Our characterization of the spatial and temporal variation inherent in continent-wide amphibian abnormalities demonstrates the disproportionate contribution of local factors in predicting hotspots, and the episodic nature of their occurrence.
Do Frogs Get Their Kicks on Route 66? Continental U.S. Transect Reveals Spatial and Temporal Patterns of Batrachochytrium dendrobatidis Infection
Michael J. Lannoo,Christopher Petersen,Robert E. Lovich,Priya Nanjappa,Christopher Phillips,Joseph C. Mitchell,Irene Macallister
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0022211
Abstract: The chytrid fungus Batrachochytrium dendrobatidis (Bd) has been devastating amphibians globally. Two general scenarios have been proposed for the nature and spread of this pathogen: Bd is an epidemic, spreading as a wave and wiping out individuals, populations, and species in its path; and Bd is endemic, widespread throughout many geographic regions on every continent except Antarctica. To explore these hypotheses, we conducted a transcontinental transect of United States Department of Defense (DoD) installations along U.S. Highway 66 from California to central Illinois, and continuing eastward to the Atlantic Seaboard along U.S. Interstate 64 (in sum from Marine Corps Base Camp Pendleton in California to Naval Air Station Oceana in Virginia). We addressed the following questions: 1) Does Bd occur in amphibian populations on protected DoD environments? 2) Is there a temporal pattern to the presence of Bd? 3) Is there a spatial pattern to the presence of Bd? and 4) In these limited human-traffic areas, is Bd acting as an epidemic (i.e., with evidence of recent introduction and/or die-offs due to chytridiomycosis), or as an endemic (present without clinical signs of disease)? Bd was detected on 13 of the 15 bases sampled. Samples from 30 amphibian species were collected (10% of known United States' species); half (15) tested Bd positive. There was a strong temporal (seasonal) component; in total, 78.5% of all positive samples came in the first (spring/early-summer) sampling period. There was also a strong spatial component—the eleven temperate DoD installations had higher prevalences of Bd infection (20.8%) than the four arid (<60 mm annual precipitation) bases (8.5%). These data support the conclusion that Bd is now widespread, and promote the idea that Bd can today be considered endemic across much of North America, extending from coast-to-coast, with the exception of remote pockets of na?ve populations.
Population, Development and Deforestation in Songea District, Tanzania  [PDF]
Michael J. Haule
Natural Resources (NR) , 2014, DOI: 10.4236/nr.2014.51004
Abstract:

Deforestation is a phenomenon that forms part of environmental degradation. The fact that deforestation is both a source and contributor to global warming, as it reduces the carbon sinks, cannot be contested [1]. A case study research was carried out in Songea Tanzania aimed at establishing whether there was differential participation of people of different demographic characteristics in those activities that lead into tree cover decline. The study revealed that people of different age group and, sex categories played different roles in activities that lead to deforestation such as felling trees for firewood and felling trees for establishing and/or for expanding farms. It was observed that age group and sex categories influenced one’s involvement or participation in deforestation thus contributing differently by both activity and degree of forest cover reduction. This literally means that people of different demographic characteristics of age and sex contributed differently to the ailing deforestation process. From this end, it is logical and implicit arguing that the identification of actors in deforestation-related activities confirms the disaggregated manner by which population acts on the environment. Development of blanket conservation packages that are not focused on age group and sex categories of members the population in question remains too general and in-effective. To be precise, the planning and implementation of effective conservation initiatives has to take into account demographic characteristics of the population in question. The observed reality is that the population engages with the environment not as a unit but in its disaggregated manner, i.e. based on its demographic sub-categories [2]. The theory behind a successful conservation initiative is based on unveiling the mechanism by which population acts when resulting to deforestation.

The Effect of NeuroGen® Nerve Support Supplement on Pillar Pain after Endoscopic Carpal Tunnel Release  [PDF]
Michael J. Fitzmaurice
Modern Plastic Surgery (MPS) , 2014, DOI: 10.4236/mps.2014.41002
Abstract:

61 patients with clinically diagnosed and electromyographically confirmed carpal tunnel syndrome were enrolled in a prospective study to evaluate the effectiveness of a nerve supplement on pillar pain after carpal tunnel surgery. All of the patients underwent endoscopic carpal tunnel release. 15 of the patients also took the nerve support supplement NeuroGen? as part of their perioperative treatment. The supplement group demonstrated a significantly lower amount of pillar pain (VAS) at initial follow up compared to the control group (1.13 and 4.05 respectively). 46% (7/15) of the supplement group were completely free of pillar pain compared to only 9% (4/46) of the control group at the first follow up. 53% (8/15) of the NeuroGen? group did not require any pain medications compared to 35% (16/46) of the control group. The Nerve supplement NeuroGen? significantly reduces pain after carpal tunnel surgery.

Changes in Human Population Characteristics and Environmental Change in the West Matogoro Catchment Area of Songea, Tanzania  [PDF]
Michael J. Haule
Natural Resources (NR) , 2014, DOI: 10.4236/nr.2014.512064
Abstract: The study was carried out in West Matogoro Catchment Area (WMCA) of Songea, Tanzania, to establish whether for the period between intercensal periods 1978-1988 and 1988-2002, and between 2002 and 2005 characteristics of human population of the area had changed in terms of size, age structure and sex composition. In case it did, then the study had to establish whether such changes may be used to explain the observed forest cover change that occurred in the area. Establishing whether the observed changes were proportionate was important in linking the relationship among factors at hand. The study partly tested the thesis by Liu and others which linked human population changes and their implications to the panda habitat [1]. The findings indicated existence of changes in human population characteristics for the period under review. Variations in terms of population size, age structure and sex composition were realized. While growth was measured by the total population and size of age group of the environmentally active population as identified by the study by Haule, sex composition was determined by sex ratios [2]. The environmentally active age group included males aged 20 to 44 and females aged 10 to 44, i.e. the key actors in felling trees for farm expansion and for firewood respectively. Geographic Information System (GIS) evidence indicated progressive forest cover deterioration. When compared, the changes in human population characteristics and those of the forest cover were noted to be un-proportional. Variations were in terms of increase in human population size and expansion of age group of the “actors” thus attributed to the augmenting deforestation. A positive relationship was demonstrated between population growth, expansion of age segment of the key actors and expanded deforestation. We reiterate that any sustainable measures to address the environmental issues should take into account changes in demographic characteristics of the in Situ population which forms the locus of the interface between population and environment. These factors signify the intensity and duration of the involved forces that characterize forest cover quality.
Nanofat and Platelet Rich Plasma to Enhance Recovery and Minimize Risk of Recurrence after Endoscopic Carpal Tunnel Release  [PDF]
Michael J. Fitzmaurice
Modern Plastic Surgery (MPS) , 2019, DOI: 10.4236/mps.2019.91002
Abstract: Carpal tunnel release is one of the most common and surgery procedures performed. Complications and recurrence of the condition can occur up to 20% of cases. We describe a technique of utilizing the nanofat and platelet rich plasma to successfully enhance healing and minimize risk of recurrence after endoscopic carpal tunnel release. This patient had exceptionally fast recovery, resuming work in one day and excellent grip strength and a full functioning level at his two-week follow-up. After one year he continues to demonstrate a complete resolution of symptoms and full function without any evidence of recurrence or complications.
The National Estuarine Research Reserve System: A Review of Research and Monitoring Initiatives  [PDF]
Michael J. Kennish
Open Journal of Ecology (OJE) , 2019, DOI: 10.4236/oje.2019.93006
Abstract: The National Estuarine Research Reserve System (NERRS) is an integrated network of 29 protected and coordinated estuarine reserve sites in 23 states and one territory (Puerto Rico) covering more than 525,000 ha of estuarine habitat, adjoining wetlands, and uplands that encompass 19 biogeographical regions along the Atlantic, Gulf of Mexico, and Pacific coasts, as well as the Caribbean Sea and Great Lakes. NERRS is an ecosystem-based research and monitoring network of sites serving as platforms to develop quantitative databases of value to coastal management programs in identifying and tracking short-term variability and long-term changes in the integrity and biodiversity of estuarine systems nationwide due to natural perturbations and anthropogenic disturbances. The reserve sites also play a vital role in assessing coastal issues of local, regional, and national significance for the purpose of sustaining estuarine systems and coastal lands, such as evaluating their responses to climate change and other major stressors to inform coastal decision-making and public awareness for the protection and resilience of natural resources and coastal communities. Over the past four decades, NERRS sites have collected large volumes of research and monitoring data of great utility in characterizing estuarine environments and addressing an array of resource-management concerns, including degraded water quality, loss and alteration of essential habitat, impacted fisheries, invasive species, and conservation.
Bayesian Learning of Climate Sensitivity I: Synthetic Observations  [PDF]
Michael J. Ring, Michael E. Schlesinger
Atmospheric and Climate Sciences (ACS) , 2012, DOI: 10.4236/acs.2012.24040
Abstract: The instrumental temperature records are affected by both external climate forcings—in particular, the increase of long-lived greenhouse gas emissions—and natural, internal variability. Estimates of the value of equilibrium climate sensitivity—the change in global-mean equilibrium near-surface temperature due to a doubling of the pre-industrial CO2 concentration—and other climate parameters using these observational records are affected by the presence of the internal variability. A different realization of the natural variability will result in different estimates of the values of these climate parameters. In this study we apply Bayesian estimation to simulated temperature and ocean heat-uptake records generated by our Climate Research Group’s Simple Climate Model for known values of equilibrium climate sensitivity, T2x direct sulfate aerosol forcing in reference year 2000, FASA, and oceanic heat diffusivity, ΔT2x. We choose the simulated records for one choice of values of the climate parameters to serve as the synthetic observations. To each of the simulated temperature records we add a number of draws of the quasi-periodic oscillations and stochastic noise, determined from the observed temperature record. For cases considering only values of ΔT2x and/or κ, the Bayesian estimation converges to the value(s) of ΔT2x and/or κ used to generate the synthetic observations. However, for cases studying FASA, the Bayesian analysis does not converge to the “true” value used to generate the synthetic observations. We show that this is a problem of low signal-to-noise ratio: by substituting an artificial, continuously increasing sulfate record, we greatly improve the value obtained through Bayesian estimation. Our results indicate Bayesian learning techniques will be useful tools in constraining the values of ΔT2x and κ but not FASA In our Group’s future work we will extend the methods used here to the observed, instrumental records of global-mean temperature increase and ocean heat uptake.
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