A point intercept survey was conducted from 2005 to 2010 on the Ross Barnett Reservoir near Jackson, MS to calculate the frequency of occurrence of all aquatic plant species in the Reservoir. style='mso-spacerun:yes'> Water lotus ( style='mso-bidiont-style:normal'>Nelumbo lutea Willd.) was the native species that occurred most often, while alligatorweed (Alternanthera style='mso-bidiont-style:normal'> philoxeroides [Mart.] Griseb.) occurred most often with regard to non-natives. A logistic regression model indicated that as species richness increases, the probability of observing a non-native species also increases. Herbicide evaluations implied that the chemical imazapyr provided the largest biomass reduction in alligatorweed over a twelve week period; however, 2,4-D would be the most economical option for long-term control. A pathogen study on alligatorweed revealed the presence of the fungus (Ceratorhiza style='mso-bidiont-style:normal'> hydrophilum [ class=SpellE>Xu, Harrington, Gleason, Et class=SpellE>Batzer, Comb., Nov. ( style='mso-bidiont-style:normal'>Sclerotium hydrophilum [Sacc.]). style='mso-spacerun:yes'> Future studies should verify the potential or lack thereof of this fungus being a biological control agent on class=SpellE>alligatorweed.

Prior studies have observed a link between night shift work and increased risk of breast cancer. Melatonin, a hormone related to circadian rhythm, has been proposed to lower breast cancer risk by inhibiting cell proliferation. The disruption of peak melatonin that occurs during night shift work could explain the increase in risk observed. Several studies have assessed whether higher melatonin levels are associated with decreased breast cancer risk, but results have been conflicting. We examined the relationship between urinary melatonin levels and breast cancer risk in a nested case-control study conducted within the Women’s Health Initiative Observational Study. First morning urine samples collected at baseline were assayed for melatonin levels in 258 women diagnosed with invasive breast cancer and 515 matched controls from three enrollment sites. Using conditional logistic regression to adjust for matching factors and established risk factors, results indicate no association between urinary melatonin levels and breast cancer risk. The mean creatinine adjusted melatonin levels for cases and controls were 16.30 ng/mg and 16.05 ng/mg, respectively. Compared to the lowest quartile of creatinine adjusted melatonin, the odds of breast cancer did not vary by quartile of creatinine adjusted melatonin, adjusted for known breast cancer risk factors: second quartile 0.84 (95% CI 0.52-1.38), third quartile 1.05 (95% CI 0.65-1.72) and fourth quartile 1.09 (95% CI 0.66-1.81). This study does not suggest that melatonin is protective against breast cancer and suggests that reasons other than melatonin suppression may explain the increased risk of breast cancer seen in night shift workers.

<p>Amur honeysuckle (<i>Lonicera maackii</i>) is a shrub endemic to East Asia which has become invasive and nearly ubiquitous to the forest ecosystems of eastern North America. Through its extended growing season, competitive ability, and potential allelopathy, Amur honeysuckle alters native herbaceous-layer plant communities and inhibits the regeneration of native tree species. As such, it is representative of a range of invasive shrub species imported from East Asia. My thesis contributes to questions fundamental to the understanding this and other invasive shrubs: 1) How do species become invasive? 2) How can the invasions of the species be effectively controlled? 3) How does the ecosystem respond to treatment of the invasive species?</p> <p>First, I examined the role of self-compatibility within Amur honeysuckle. I compared the berry production, seed production, and germination rates between closed-pollinated and open-pollinated flowering branches of Amur honeysuckle individuals across multiple types of invasions (heavy, light, and sprouting). I found that Amur honeysuckle not only possesses the ability to self-pollinate, but that it can produce viable self-pollinated seed sets. This ability may help explain how Amur honeysuckle able to invade isolated forest patches far removed from the main invasion.</p> <p>Second, I evaluated the effectiveness of a novel herbicide adjuvant in reducing the amount of herbicide needed in the ‘cut-stump’ method of controlling Amur honeysuckle. Combining various concentrations of the most common herbicide in the world, glyphosate, with concentrations of cellulases derived from fungi, 2XL, I examined whether the cellulases improved the effectiveness of glyphosate, potentially by increasing glyphosate movement into the vascular tissue of Amur honeysuckle through the degradation of cell walls. While 2XL was not an effective adjuvant, glyphosate concentrations of less than half the recommended dosages were equally effective as higher concentrations in preventing sprouting of treated stumps. The ineffectiveness of 2XL may imply a need for protein-mitigated diffusion of glyphosate across cell walls and into the vascular tissue of the plant, which would be inhibited by the breakdown of cell walls.</p> Finally, I tested how deeper intensities of mulching-head treatments affected the sprouting response of Amur honeysuckle and the response of the herbaceous-layer plant community after treatment. I found a negative relationship between the volume of sprouting Amur honeysuckle and increasing depth of mulching-head treatment. Additionally, increasing mulching-head intensities were correlated with increased herbaceous layer diversity and conservation value as represented by Floristic Quality Index. Mulching-head treatments are a promising tool in controlling heavy invasions of non-native shrubs.

Approximately 90% of flowering plants depend on pollinators for reproduction. The stability and effectiveness of plant-pollinator interactions are crucial for ecosystem function. Increasing numbers of non-native plants are naturalized in plant communities and may alter pollination success of native plant species. Thus, invasive species have the potential to alter community function and stability. However, the effects of invasive species on community-wide plant-pollinator interactions are poorly understood. While the effects of invasive species on the structure of plant-pollinator networks are well studied. However, these studies have relied on pollinator visitation data that is only one component of the pollination process. Thus, the effects of invasive species on pollen transport and pollen transfer dynamics remain unknown and this may misrepresent the true nature of invasive effects on community-wide plant-pollinator interactions. Pollen transport networks may give more accurate representations of plant-pollinator interactions by providing information on pollen collection by floral visitors. Therefore, in this study I evaluate the effect of the invasive Cirsium arvense on pollen transport networks to improve our understanding of the impact that invasive plants have on community-wide plant-pollinator interactions. Pollinators were collected on one invaded and one non-invaded site once weekly throughout the flowering season (May- August of 2017). Pollen was isolated for each insect and pollen samples were identified with a pollen reference library and counted using a hemocytometer. 154 insect morphospecies were collected carrying 73 pollen species. Preliminary results indicate that Cirsium arvense has no impact on network structure: connectance (0.15 and 0.18), link density (3.01 and 2.23), and weighted nestedness (0.68 and 0.75), for invaded and non-invaded respectively. However, the role of individual species within the network seems to vary between sites suggesting that Cirsium arvense may change community dynamics (identity of species-pair interactions). Future analysis will evaluate invasive species effects at the species level.

Invasions of exotic species are one of the primary causes of biodiversity loss on our planet (National Research Council 1995). In the marine environment, all habitat types including estuaries, coral reefs, mud flats, and rocky intertidal shorelines have been impacted (e.g. Bertness et al. 2001). Recently, the topic of invasive species has caught the public's attention. In particular, there is worldwide concern about the aquarium strain of the green alga Caulerpa taxifolia (Vahl) C. Agardh that was introduced to the Mediterranean Sea in 1984 from the Monaco Oceanographic Museum. Since that time, it has flourished in thousands of hectares of near-shore waters. More recently, C. taxifolia has invaded southern Californian and Australian waters. Since the waters of Florida are similar to the waters of the Mediterranean Sea and other invasive sites my study will focus on determining potential invasion locations in Florida. I will look at the present distribution of C. taxifolia - native strain in Florida as well as the distribution of the whole genus around the state. During this study, I address three questions: 1) What is the current distribution of Caulerpa spp. in Florida? 2) Can I predict the location of potential Caulerpa spp. invasions using a set of environmental parameters and correlate them to the occurrence of the algae with the support of Geographic Information System (GIS) maps? 3) Using the results of part two, is there an ecological preferred environment for one or all Caulerpa spp. in Florida? To answer these questions, I surveyed 24 areas in each of 6 zones chosen in a stratified manner along the Floridian coastline to evaluate the association of potential indicators Caulerpa. Latitude, presence or absence of seagrass beds, human population density, and proximity to marinas were chosen as the 4 parameters expected to correlate to Caulerpa occurrences. A logistic regression model assessing the association of Caulerpa occurrence with measured variables has been developed to predict current and future probabilities of Caulerpa spp. presence throughout the state. Fourteen different species of Caulerpa spp. were found in 26 of the 132 sites visited. There was a positive correlation between Caulerpa spp. and seagrass beds presence and proximity to marinas. There was a negative correlation with latitude and human population density. C. taxifolia – aquarium strain wasn't found. Percent correct for our model was of 61.5% for presence and 98.1% for absence. This prediction model will allow us to focus on particular areas for future surveys.

Mangrove ecosystems are critical to Florida, providing economic resources to humans, and untold ecological resources to estuarine organisms. In Florida's estuaries, mangrove ecosystems have suffered significant losses due to natural and human disturbances; these disturbances potentially leave mangrove communities vulnerable to invasion by the opportunistic exotic, Schinus terebinthifolius (Brazilian pepper). Prior experiments have suggested that Schinus terebinthifolius is unable to survive under marine conditions and poses no long term threat to mangrove systems. However, this contradicts field observations where Schinus terebinthifolius was found growing in the intertidal zone of Mosquito Lagoon alongside three native species of mangroves, Rhizophora mangle, Avicennia germinans and Laguncularia racemosa. The purpose of my study was to evaluate competition between the invasive S. terebinthifolius and these three native species of mangroves in the coastal estuarine system along the east coast of Central Florida in Canaveral National Seashore. The effects of competition were evaluated by testing the ability of S. terebinthifolius to: 1) chemically inhibit growth of mangrove propagules, 2) invade new coastal habitats by dispersing seeds in the water, 3) alter species richness and abundance of the flora when present in a mangrove system, and 4) recruit and survive in mangrove habitat. By better understanding the invasibility and impact of Schinus terebinthifolius on mangroves, coastal resource managers will be able to develop the most effective management strategies to prevent this exotic from altering the structure and productivity of the mangrove ecosystem.

Mosquitofish (Gambusia holbrooki) are native to the southeastern United States but invasive elsewhere, and are dominant predators in many ecosystems that they inhabit. Information on dispersal behavior will help better understand and predict mosquitofish metapopulation dynamics and invasions. I experimentally tested dispersal behavior of individual mosquitofish under a range of laboratory conditions relevant to field situations. Preliminary experiments showed that gender, lighting conditions, hunger and acclimation time did not significantly affect net dispersal rate. Power analysis based on this preliminary experiment determined that 6 replicate fish were sufficient for each subsequent experiment; I used 24 fish, and each fish was tested one time. Three factors that potentially could affect net swimming rate were tested: habitat of origin (permanent vs. temporary waters), water depth (3-24 mm), and the interaction between water depth and leaf litter type (upland and wetland). Fish from a temporary pond dispersed significantly faster than fish from a permanent pond, and fish dispersed significantly faster in deeper water than in shallower water. However, leaf litter significantly inhibited fish dispersal at all depths tested. Based on these experiments, G. holbrooki disperse more readily through relatively open and deeper (several centimeters) pathways between habitats such as roadside ditches, drainage canals and trails in flooded conditions. My results are useful for understanding mosquitofish dispersal behavior based on the abiotic and biotic factors examined in this experiment. I predict that mosquitofish can spread from a point of introduction at about 800 m per day, given and unobstructed path of only > 6 mm depth.

Invasions by alien understory plant species have gradually become a worldwide challenge in maintaining forest biodiversity and ecosystem productivity. Notably, Microstegium vimineum, a C4 grass native to Japan, has increased dominance in mixed deciduous hardwood forests of the southeastern United States, largely due to its shade tolerance and ability to spread through rhizomes. Microstegium vimineum also proliferates after prescribed fire, a common management tool used in the region to restore forests to desired conditions, and may compete with hardwood seedlings, hindering restoration efforts. Using two upland deciduous hardwood forest research sites in Marshall and Tate Counties, Mississippi, this study measured competitive effects of Microstegium vimineum on native hardwood seedling growth and survival with and without prescribed fire treatments. A single burning had no significant effect on Microstegium vimineum abundance, while the effect of Microstegium vimineum on seedling growth and survival varied by species.

Recent estimates have revealed that more than 6.5 million olive trees in southern Italy have subdued to the Xylella fastidiosa infection, leading to the devasting Olive Quick Decline Syndrome (OQDS). This epidemic continues to expand, posing a significant threat to global olive oil production. OQDS has already resulted 30-34% reduction in ecosystem services provided by olive orchards and a 28% decline in associated biodiversity. Additionally, OQDS has annihilated productivity and the entire olive oil supply chain, causing considerable economic losses. To counteract the relentless spread of Xylella, Integrated Transmission Management (ITM) strategies are crucial. Reducing one vector per olive tree present in an olive orchard can confine X. fastidiosa within acceptable economic and environmental limits. Thus, monitoring and managing vector populations are crucial to curbing disease transmission. The complex interactions between insects and microorganisms are pivotal in the OQDS scenario. Understanding these interactions can provide insights into novel control strategies, such as disrupting bacterial symbiosis with Aphrophoridae foams, affecting the fitness of vector insects, and potentially reducing X. fastidiosa transmission. To counteract Xylella transmission effectively, biocontrol measures must be incorporated into IPM strategies for olive orchards. However, more than the current arsenal of vector antagonists is required. The entrance into the Europe of Zelus renardii shows promise in biocontrolling Xylella vectors. Furthermore, Z. renardii's ability to manage other olive pests adds to its utility. Zelus renardii's bionomics and its ability to regulate alarm pheromones via Brindley glands is crucial for its effective use in IPM strategies. The formulation of artificial diets for mass-rearing Z. renardii under controlled conditions can pave the way for its inundative release to enhance ITM. These biological and biotechnological control measures have the potential to significantly reduce Philaenus spumarius populations and the infective capacity of Xylella vectors within IPM strategies. This approach can also act preventively and protectively, reducing the risk of future infections and limiting repeated transmissions. Progress has been made in modulating the transmission abilities of Xylella vectors, while the challenge of OQDS and X. fastidiosa remains tricky. The availability of Z. renardii and exploring its capabilities offer a more sustainable and effective approach to managing this disease in olive production.

Background: Pediatric minimally invasive surgery (MIS) is a standard technique worldwide. We aimed to analyze the research activity in this field. Methods: Articles on pediatric MIS (1991–2020) were analyzed from the Web of Science ™ for the total number of publications, citations, journals, and impact factors (IF). Of these, the 50 most cited publications were evaluated in detail and classified according to the level of evidence (i.e., study design) and topic (i.e., surgical procedure). Results: In total, 4464 publications and 53,111 citations from 684 journals on pediatric MIS were identified. The 50 most cited papers were published from 32 institutions in the USA/Canada (n = 28), Europe (n = 19 ), and Asia (n = 3) in 12 journals. Four authors (USA/Europe) contributed to 26% of the 50 most cited papers as first/senior author. Hot topics were laparoscopic pyeloplasty (n = 9), inguinal hernia repair (n = 7), appendectomy, and pyloromyotomy (n = 4 each). The majority of publications were retrospective studies (n = 33) and case reports (n = 6) (IF 5.2 ± 3.2; impact index 16.5 ± 6.4; citations 125 ± 39.4). They were cited as often as articles with high evidence levels (meta-analyses, n = 2; randomized controlled trials, n = 7; prospective studies, n = 2) (IF 12.9 ± 22.5; impact index 14.0 ± 6.5; citations 125 ± 34.7; p > 0.05). Conclusions: Publications on laparoscopic pyeloplasty, inguinal hernia repair, appendectomy, and pyloromyotomy are cited most often in pediatric MIS. However, the relevant number of studies with strong evidence for the advantages of MIS in pediatric surgery is missing