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1.
Parastrongylus (=Angiostrongylus) cantonensis, a lung worm of rats, was first reported in the United States in 1987, with a probable introduction by infected rats from ships docking in New Orleans, Louisiana, during the mid-1980s. Since then, it has been reported in nonhuman primates and a boy from New Orleans, and in a horse from Picayune, Mississippi, a distance of 87 km from New Orleans. Parastrongylus cantonensis infection is herein reported in a lemur (Varencia variegata rubra) from New Iberia, Louisiana, a distance of 222 km from New Orleans, and in a wood rat (Neotomafloridanus) and in 4 opossums (Didelphis virginiana) from Baton Rouge, Louisiana, a distance of 124 km from New Orleans. The potential of a great variety of gastropods serving as intermediate hosts in Louisiana may pose a threat to wildlife as well as to domesticated animals in the areas where infected Norway rats (Rattus norvegicus) are present.  相似文献   

2.
The Deason House is located in the heart of the Piney Woods region in the town of Ellisville, Mississippi. During the American Civil War, the Deason House became the epicenter for an event that started a rebellion against the Confederate government. On 5 October 1863, a Confederate deserter named Newton Knight allegedly shot and killed Confederate Major Amos McLemore in the Deason House, which eventually lead to the formation of the Free State of Jones. Despite the historical importance of the house, oral accounts and written documents have failed to provide accurate construction history of the structure. We coupled techniques of dendrochronology and geophysical survey to better understand the construction history of the Deason House and cultural activities of its inhabitants. We extracted 35 Pinus palustris (Mill.) timbers along the west-facing exterior weatherboards and from various logs within the second-floor attic, 25 of which were successfully crossdated against a P. palustris reference chronology located 15 km south in De Soto National Forest (1742–2013). The Deason House chronology anchored against the De Soto time series during the period 1742–1875 (r = 0.55, t = 4.01, p < 0.0001) and extended the reference chronology back to the year 1680 CE. Clustering of cutting- and near-cutting dates from timbers revealed 3 possible stages of construction. First, the house likely existed as a single-pen structure built in the winter of 1835/1836, based on two timbers with wane/bark that were affixed to the original chimney made of clay bricks fired on the homestead. Second, based on the clustering of 1855 cutting dates, we suggest this was the most likely time the original structure was expanded with a vestibule, porch, and larger 4-room house. Finally, six timbers revealed a back addition was constructed in the year 1866. Ground penetrating radar (GPR) helped provide evidence mentioned in written records that the back addition (1866) existed as the detached kitchen then was affixed to the structure ca. 1890. The GPR data revealed geophysical anomalies that indicated the original sites of the detached kitchen, water well, livestock pen, privies, and trash pit. Through the use of dendrochronological analyses and geophysical survey, we were able to provide an updated history of the Deason House construction dynamics and cultural activities of its inhabitants beyond the historical record.  相似文献   

3.
The large river swamps of Louisiana have complex topography and hydrology, characterized by black willow (Salix nigra) dominance on accreting alluvial sediments and vast areas of baldcypress (Taxodium distichum) deepwater swamps with highly organic substrates. Seedling survival of these two wetland tree species is influenced by their growth rate in relation to the height and duration of annual flooding in riverine environments. This study examines the interactive effects of substrate, hydroperiod, and nutrients on growth rates of black willow and baldcypress seedlings. In a greenhouse experiment with a split-split-plot design, 1-year seedlings of black willow and baldcypress were subjected to two nutrient treatments (unfertilized versus fertilized), two hydroperiods (continuously flooded versus twice daily flooding/draining), and two substrates (sand versus commercial peat mix). Response variables included height, diameter, lateral branch count, biomass, and root:stem ratio. Black willow growth in height and diameter, as well as all biomass components, were significantly greater in peat substrate than in sand. Black willow showed a significant hydroperiod–nutrient interaction wherein fertilizer increased stem and root biomass under drained conditions, but flooded plants did not respond to fertilization. Baldcypress diameter and root biomass were higher in peat than in sand, and the same two variables increased with fertilization in flooded as well as drained treatments. These results can be used in Louisiana wetland forest models as inputs of seedling growth and survival, regeneration potential, and biomass accumulation rates of black willow and baldcypress.  相似文献   

4.
Hurricane Katrina devastated New Orleans, Louisiana, USA, causing widespread damage to industry, housing, and infrastructure. The area of New Orleans East was particularly devastated, including a cluster of industries, such as a major food-processing plant, manufacturing facilities, and bulk material and gas processors. Although this area was well suited for resource recovery and eco-industrial linkages, little progress has been made in implementation. This article explores New Orleans as a case study in the application of industrial ecology to disaster management. Hurricane Katrina's damage to New Orleans resulted in a significant increase in the amount of waste flowing into New Orleans East, which precipitated a massive expenditure of federal funds toward debris management. Those circumstances created an unprecedented opportunity to capitalize a resource recovery program and to establish eco-industrial relationships, both of which would have resulted in new jobs and environmental improvement. Yet straightforward opportunities for resource recovery and eco-industrial linkage were overlooked or dismissed, in spite of antilandfill activism from the environmental community and formal recommendations for recycling from scientists and other professionals. We describe the specific resource recovery and eco-industrial opportunities that were available to New Orleans East, especially those that were magnified by Hurricane Katrina, and analyze the barriers that prevented their actualization. We also provide recommendations for overcoming barriers to resource recovery and eco-industrial progress with the goal that future postcatastrophe scenarios may benefit from more effective use of relief and recovery funding.  相似文献   

5.
This essay was delivered as the Distinguished Lecture at the 89th annual meeting of the American Anthropological Association, December 1, 1990, in New Orleans, Louisiana.  相似文献   

6.
This article was presented as the second annual Distinguished Lecture in Archeology at the 89th annual meeting of the American Anthropological Association, November 30, 1990, in New Orleans, Louisiana.  相似文献   

7.
A detailed dendrochronological survey was performed on the medieval roofs of the Church of Our Lady (CoOL) in Damme, Belgium. Seen its complex architectural history, special attention was paid to the identification of consecutive building phases, based on combined architectural historical research and tree-ring dating. In total 64 increment cores were taken throughout the roof structures of the CoOL. All roof timbers are made of European oak (Quercus robur/petraea), of which only few have surviving sapwood or bark. Tree-ring dating confirms the late 13th/early 14th century construction date of the roofs. For all chronologies that were composed, the highest correlation values are found with reference chronologies covering the catchment area of the river Meuse. From the dating results of the timbers of the CoOL it becomes clear that the same timber source was used for nearly a century. On several of the examined roof timbers, rafting joints were observed, demonstrating that the timbers were indeed tied together as a raft and floated down the river.By implementing sapwood estimates in a Bayesian chronological model (OxCal), tree-ring series with surviving sapwood from coeval roof structures were combined in order to narrow down the time range for the felling date. Based on the refined interpretation of the felling dates, several consecutive building phases can now be identified and dated, leading to a new interpretation of the architectural history of the CoOL. Intriguingly, a marked interruption in building activities is observed around 1300. Probably this is related to the instable political situation at that time, caused by the armed conflict that emerged between the Count of Flanders and the king of France. Since Damme served as the outport of the riotous city of Bruges, it was alternately seized by the French and Flemish, both consuming considerable amounts of timber and other building materials for military fortifications. Potentially this led to a shortage in building materials and provoked a stop in building activities.This paper demonstrates the power of Bayesian models to refine the interpretation of dendrochronological dates in architectural analyses of medieval historical buildings.  相似文献   

8.
Summary The Formosan subterranean termite (Coptotermes formosanus Shiraki) was first sighted in the cities of New Orleans and Lake Charles, Louisiana, in 1966. Its distribution in the historic French Quarter of New Orleans 23 years later (1989) and in 1991 and 1992 is reported here using counts of alates from light-traps. Light-trappings revealed a Quarter-wide distribution of the termite.C. formosanus shows an extended pause in flight behavior in the middle of the two-month flight season that is predictable and independent of weather. A colony-level mechanism, namely, developmental inhibition of nymphs by alates, may regulate this intermission in flight. The sex-ratio of light-trapped alates varies over time, but is generally female-biased, especially at the height of the flight season.  相似文献   

9.
Turner  R. E.  Dortch  Q.  Justic'  D.  Swenson  E. M. 《Hydrobiologia》2002,487(1):137-152
We constructed a nitrogen loading budget for the Lake Pontchartrain watershed located north of New Orleans, Louisiana (U.S.A.). Water quality measurements, discharge estimates, and literature values were used to establish the annual and seasonal variations in loading rates for total nitrogen and nitrate. The relatively stable annual loadings (million kg N) are about 10× that of the pre-settlement nitrogen loading, and come from atmosphere (1.3), the watershed (7.8), pumped urban runoff from New Orleans (1.0), and leakage through the Bonnet Carré flood control structure (0.5–0.9). Relatively minor additional amounts come from nitrogen fixation in the Lake. Occasional openings of the Bonnet Carré Spillway (for flood protection) could triple the annual average loading within 1–2 months. Proposed smaller diversions (for wetland restoration) could raise present N loadings by 50%. The results of water quality management, flood protection and wetland restoration may thus have conflicting effects on the Lake's phytoplankton community, which is primarily nitrogen limited. Lowering the total nitrogen loading, however, seems quite possible, especially given that the present loadings are almost all reducible through existing technology, especially sewerage treatment. The analysis demonstrates that the consequences of ecosystem restoration efforts, continued population growth and flood protection to estuarine nitrogen budgets are intertwined with each other, have a seasonal component, and are changing as policies evolve.  相似文献   

10.
Hurricane Sandy in late October 2012 drove before it a storm surge that rose to 4.28 meters above mean lower low water at The Battery in lower Manhattan, and flooded the Hugh L. Carey automobile tunnel between Brooklyn and The Battery. This study examines the surge event in New York Harbor using the Weather Research and Forecasting (WRF) atmospheric model and the Coupled-Ocean-Atmosphere-Wave- Sediment Transport / Regional Ocean Modeling System (COAWST/ROMS). We present a new technique using directional analysis to calculate and display maps of a coastline''s potential for storm surge; these maps are constructed from wind fields blowing from eight fixed compass directions. This analysis approximates the surge observed during Hurricane Sandy. The directional analysis is then applied to surge events at Charleston, South Carolina, New Orleans, Louisiana, and Tacloban City, the Philippines. Emergency managers could use these directional maps to prepare their cities for an approaching storm, on planning horizons from days to years.  相似文献   

11.
This paper documents the history of the introduction of the soybean (Glycine max), a domesticate of China, to North America. Henry Yonge, the Surveyor-General of Georgia, planted soybeans on his farm at the request of Samuel Bowen in 1765. Mr. Bowen, a former seaman employed by the East India Company, brought soybeans to Savannah, Georgia, from China via London. From 1766, Mr. Bowen planted soybeans on his plantation “Greenwich” located at Thunderbolt, Georgia. The soybeans were used to manufacture soy sauce and vermicelli (soybean noodles). In addition, he manufactured a sago powder substitute made from sweet potatoes. The 3 products were then exported to England. Samuel Bowen received a patent for his manufacturing inventions for producing these products. Another early introduction of soybeans to North America was by Benjamin Franklin. In 1770 he sent seeds from London to John Bartram in Philadelphia.  相似文献   

12.
The structure named Rebel’s Rest was a two-story, Reconstruction-era house located on the campus of the University of the South in Sewanee, Tennessee, before being severely damaged by fire in July 2014. The house was constructed of squared timbers and round logs, with later additions built using sawn lumber. Dendrochronological analyses of timbers and logs salvaged from the house reveals wood from four genera: oak (Quercus spp.), tulip poplar (Liriodendron tulipifera L.), American chestnut (Castanea dentata [Marshall] Borkh.), and pine (Pinus spp.). We statistically and graphically crossdated a total of 251 samples (24,410 rings) with regional chronologies from the ITRDB, resulting in three dated chronologies comprised of oak (1645–1874), tulip poplar (1725–1865), and American chestnut (1710–1864). The majority of samples with cutting dates (95.6%) ended in years 1865–1866, confirming the historically reported construction date of 1866 for the initial structure. The cutting date analysis also confirms two rooms as later additions, Room M (1867) and Room B (1875). Based on ring count and the number of chronologies produced, this research represents the largest known dataset from a single historic structure in the Southeastern US.  相似文献   

13.
The annual rings in suitable living trees have provided significant, centuries-long histories of past rainfall, temperature and river flow for many regions and have served to precisely date several hundred Southwestern ruins by overlap-matching with ancient timbers. Some of the stunted trees in very adverse environments were found to have the most sensitive chronologies and to attain ages twice or more the usual maxima on optimum sites. Tree-ring data for the western United States show that in pre-Columbian times the accumulated excess or deficit in rainfall occasionally greatly exceeded that recorded by gages during the past decades.  相似文献   

14.
Treatment of milfoil seedlings with NaCl results in disruptionof the cell wall and membranes and in depressed photosynthesis,respiration, and Na accumulation. Addition of low levels ofCa to NaCl treatment solutions inhibited these toxic effects. 1Present address: Department of Anatomy, School of Medicine,Tulane University, New Orleans, Louisiana 70118, U.S.A. (Received January 16, 1974; )  相似文献   

15.
The Alu family of intersperesed repeats is comprised of ovr 500,000 members which may be divided into discrete subfamilies based upon mutations held in common between members. Distinct subfamilies of Alu sequences have amplified within the human genome in recent evolutionary history. Several individual Alu family members have amplified so recently in human evolution that they are variable as to presence and absence at specific loci within different human populations. Here, we report on the distribution of six polymorphic Alu insetions in a survey of 563 individuals from 14 human population groups across several continents. Our results indicate that these polymorphic Alu insertions probably have an African origin and that there is a much smaller amount of genetic variation between European populations than that found between other populations groups. Present address: Department of Pathology, Stanley S. Scott Cancer Center, Louisiana State University Medical Center, 1901 Perdido St., New Orleans, LA 70112 Correspondence to: M.A. Batzer  相似文献   

16.
Recent studies have suggested that some patients may not obtain the full benefits of aspirin's antiplatelet effects. An international roundtable of experts was held November 6, 2004, in New Orleans, Louisiana, to address the concept of aspirin resistance and its clinical implications. Panelists discussed various definitions and possible mechanisms of aspirin resistance, along with several tests currently available to measure platelet function. They recommended that until the clinical importance of these tests is known, physicians should continue to prescribe low-dose aspirin therapy for individuals at high risk for cardiovascular events and patients currently taking aspirin should continue to comply with their prescribed therapy.  相似文献   

17.
Caribbean flamingos were observed during the 1981 breeding season at the Audubon Zoological Garden in New Orleans, Louisiana. Two floods occurred during the breeding season, causing the flock to nest three times. At each new nesting there was a significant decline in the number of birds laying eggs. One pair brooded a chick during the final nesting. Immediately after hatching, the female usually brooded while the male defended the nest area; however, over the three-day period that the chick remained on the nest, the male began to spend more time brooding and less time defending the nest area. Thus there appeared to be some division of labor in this flamingo pair.  相似文献   

18.
Differentiation of cotton fibers from single cells in suspension culture   总被引:3,自引:0,他引:3  
Summary A cotton cell suspension culture has been developed that provides unique opportunities for plant biologists to investigate early developmental events regulating cotton fiber properties, plant cell elongation, and cell wall biogenesis. The suspension culture was derived from cells of cotton (Gossypium hirsutum L.) ovule callus. These cells undergo the stages of fiber development previously described for in vivo fiber development. Fibers range in length up to 11 mm and have secondary walls. Supported by the U.S. Department of Agriculture, Agricultural Research Service, Southern Regional Research Laboratory, New Orleans, Louisiana, and Cotton Incorporated, Raleigh, North Carolina.  相似文献   

19.
We analyzed the business reopening process in New Orleans after Hurricane Katrina, which hit the region on August 29, 2005, to better understand what the major predictors were and how their impacts changed through time. A telephone survey of businesses in New Orleans was conducted in October 2007, 26 months after Hurricane Katrina. The data were analyzed using a modified spatial probit regression model to evaluate the importance of each predictor variable through time. The results suggest that the two most important reopening predictors throughout all time periods were the flood depth at the business location and business size as represented by its wages in a logarithmic form. Flood depth was a significant negative predictor and had the largest marginal effects on the reopening probabilities. Smaller businesses had lower reopening probabilities than larger ones. However, the nonlinear response of business size to the reopening probability suggests that recovery aid would be most effective for smaller businesses than for larger ones. The spatial spillovers effect was a significant positive predictor but only for the first nine months. The findings show clearly that flood protection is the overarching issue for New Orleans. A flood protection plan that reduces the vulnerability and length of flooding would be the first and foremost step to mitigate the negative effects from climate-related hazards and enable speedy recovery. The findings cast doubt on the current coastal protection efforts and add to the current debate of whether coastal Louisiana will be sustainable or too costly to protect from further land loss and flooding given the threat of sea-level rise. Finally, a plan to help small businesses to return would also be an effective strategy for recovery, and the temporal window of opportunity that generates the greatest impacts would be the first 6∼9 months after the disaster.  相似文献   

20.
Because of their dominance in swamps of the southeastern United States, baldcypress (Taxodium distichum) trees are commonly used in wetland restoration. Though baldcypress are known to tolerate moderate flooding and salinity, their growth has been shown to decrease when they experience drought and high salinity. This study examined the effects of drought and elevated salinity on the growth of baldcypress seedlings and saplings. In a restored wetland in North Carolina, we examined the growth of 8‐year‐old baldcypress by measuring height and diameter at breast height (DBH) along salinity, nutrient, and flooding gradients. In a greenhouse, we placed 1‐year‐old baldcypress seedlings in either drought or saturated conditions and applied different water treatments: fresh water, sulfate, and artificial salt water (5 ppt [parts per thousand]). Over 26 weeks, we measured diameter at root collar, height, and biomass. In the field, chloride concentrations in soil solution had a negative effect on DBH and height (51 and 36% decrease, respectively); high water levels had a negative effect on height (47% decrease) and DBH (46% decrease). In the greenhouse, both drought and salinity decreased diameter growth (43 and 61% decline, respectively) and height (64 and 43% decline, respectively). Sulfate did not have a significant effect on diameter growth, but caused a 14% decrease in height. Our results suggest that both drought and salinity (even as low as 1 ppt) can lead to a 20–60% decline in baldcypress growth. Restoration practitioners should consider the negative consequences of both drought and increased salinity on baldcypress growth when planning for wetland restoration.  相似文献   

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