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Kinds of Beach Terms modified by Beach Selected AbstractsPHYCOLOGISTS AND PROTOZOOLOGISTS JOIN FOR ANNUAL MEETINGS IN GLENEDEN BEACHJOURNAL OF PHYCOLOGY, Issue 3 2003Article first published online: 27 MAY 200 No abstract is available for this article. [source] HOTELLING'S BEACH WITH LINEAR AND QUADRATIC TRANSPORTATION COSTS: EXISTENCE OF PURE STRATEGY EQUILIBRIA,AUSTRALIAN ECONOMIC PAPERS, Issue 1 2007ALAIN EGLI In Hotelling type models consumers have the same transportation cost function. We deviate from this assumption and introduce two consumer types. Some consumers have linear transportation costs, while the others have quadratic transportation costs. If at most half the consumers have linear transportation costs, a subgame perfect equilibrium in pure strategies exists for all symmetric locations. Furthermore, no general principle of differentiation holds. With two consumer types, the equilibrium pattern ranges from maximum to intermediate differentiation. The degree of product differentiation depends on the fraction of consumer types. [source] Sensitivity of post-hurricane beach and dune recovery to event frequencyEARTH SURFACE PROCESSES AND LANDFORMS, Issue 5 2009Chris Houser Abstract The recovery of Santa Rosa Island in northwest Florida is characterized following Hurricane Katrina (September 2005), which was preceded by Hurricanes Ivan (2004) and Dennis (2005). Beach and dune recovery were quantified to the east and west of Pensacola Beach through a comparison of LiDAR data collected immediately following Hurricane Katrina and in July 2006 after almost a year of recovery. East of Pensacola Beach (the Santa Rosa Unit), the shoreline retreated by an average of 64 m during the 2004,2005 hurricane season and recovered by an average of 19 m. To the west of Pensacola Beach (the Fort Pickens Unit), the shoreline retreated by an average of 30 m, and while no significant shoreface recovery was observed, the presence of vegetation on low-profile dunes promoted backshore accretion. It is found that beachface recovery in the Santa Rosa Unit and backshore accretion in the Fort Pickens Unit occurred at the widest sections of the island where the pre-storm profile volume had been relatively large and overwash penetration was at a minimum. The narrow sections of the island (between cuspate headlands) had a smaller profile volume before the storms, leading to greater overwash penetration and in some cases island breaching in both sections, which limited the volume of sediment available for shoreface recovery. The alongshore variation in recovery is not only related to the island width, but also the offshore bathymetry, height of the pre-storm dunes and the overwash penetration. If sufficient time is allowed for the return of vegetation and the recovery of the dunes, the variations in storm impact observed during Hurricane Ivan will be reinforced during subsequent storms. In this respect, the level of impact during subsequent storms and the ability of the island to recover will depend on the frequency of storm events. Copyright © 2009 John Wiley & Sons, Ltd. [source] Instability investigation of cantilevered seacliffsEARTH SURFACE PROCESSES AND LANDFORMS, Issue 11 2008Adam P. Young Abstract Wave action is a fundamental mechanism in seacliff erosion, whereby wave undercutting creates an unstable cantilevered seacliff profile and can lead to large catastrophic cliff failures, thus threatening coastal infrastructure. This study investigated the instability of two such failures that occurred in Solana Beach, California, by combining terrestrial LIDAR scanning, cantilever beam theory and finite element analysis. Each landslide was detected by evaluating the surface change between subsequent high resolution digital terrain models derived from terrestrial LIDAR data. The dimensions of failed cantilever masses were determined using the surface change measurements and then incorporated into failure stress analysis. Superimposing stress distributions computed from elastic cantilever beam theory and finite element modeling provided a method to back-calculate the maximum developed tensile and shear stresses along each failure plane. The results of the stress superposition revealed that the bending stresses caused by the cantilevered load contributed the majority of stress leading to collapse. Both shear and tensile failure modes were investigated as potential cliff failure mechanisms by using a comparison of the back-calculated failure stresses to material strengths found in laboratory testing. Based on the results of this research, the tensile strength of the cliff material was exceeded at both locations, thus causing the cliffs to collapse in tension. Copyright © 2008 John Wiley & Sons, Ltd. [source] EVOLUTION OF POECILOGONY AND THE BIOGEOGRAPHY OF NORTH AMERICAN POPULATIONS OF THE POLYCHAETE STREBLOSPIOEVOLUTION, Issue 4 2000Stefan R. Schulze Abstract. Invertebrate interspecific developmental patterns can be highly variable and, taxonomically, are considered only weakly constrained. Intraspecifically, some invertebrate species possess multiple developmental modes,a condition known as poecilogony. Closer examination of most putative poecilogenous species, however, has not supported poecilogony, but rather has uncovered hidden or cryptic species. The polychaete Streblospio benedicti is a well-known, poecilogenous species found along the coast of North America. We collected mitochondrial cytochrome subunit I DNA sequence data from 88 individuals taken from 11 locations along the Atlantic, Gulf, and Pacific Coasts of the United States to provide a phylogenetic framework from which to interpret intraspecific variation in larval life history and brooding structure morphology in this species. Our results are consistent with a recent revision of the species into two separate species: S. benedicti, a pouched brooding form distributed along the Atlantic and Pacific Coasts, and S. gynobranchiata, a branchiate brooding form in the Gulf of Mexico. Contrary to the redescription, S. benedicti is paraphyletic because the pouched brooding population in Vero Beach, Florida shows strong genetic affinity with Gulf of Mexico populations (S. gynobranchiata). However, S. benedicti is a true poecilogenous species, with both lecithotrophic and planktotrophic individuals possessing identical mitochondrial DNA haplotypes. Crossbreeding experiments further support the molecular phylogeny with reproductive isolation demonstrated between, but not within, the major phylogenetic clades consistent with the previously described species. The genetic break near Vero Beach, Florida, corresponds to a well-known phylogeographic boundary, but the estimated time of separation for the Streblospio spp., approximately 10 million years before present, predates all other known phylogeographic subdivisions in this area. This suggests that biogeographic sundering in this region is a recurrent event. Divergence times within the major Streblospio spp. clades are recent and indicate that changes in larval life history as well as brooding structure morphology are highly plastic and can evolve rapidly. [source] Tidal Effects on Ground Water Discharge Through a Sandy Marine BeachGROUND WATER, Issue 7 2004Daniel W. Urish Tidal fluctuations along the salt water boundary of a sandy beach affect the magnitude, location, timing, and salinity of both subaerial and submarine ground water discharge. Detailed studies of shoreline discharge from an unconfined aquifer at two sites in an embayment on the Cape Cod, Massachusetts, coastline provide insight into the highly dynamic spatial and temporal nature of discharge along sandy beaches affected by the tide. The constantly moving tidal boundary over a sloping beach results in a shoreline-perpendicular discharge zone of 10 to 20 m, with ,35% to 55% of the discharge being submarine discharge. The distribution of fresh ground water through a beach face varies greatly, depending primarily on the tidal cycle and range, the heterogeneous characteristics of the beach sediments, and the beach geometry. The estimated relative volume of discharge varies temporally with tidal fluctuations, with the greatest discharge occurring during early to mid ebbing tide and location of greatest estimated discharge moving seaward during ebbing tide. This is determined using net hydraulic head calculations in monitoring wells set in a shoreline-perpendicular transect in the beach. The salinity of discharge varies temporally from near fresh water values of 1 part per thousand (ppt) to near coastal salt water values of 30 ppt, being saltiest at the start of discharge as the tide ebbs and freshest during a low tide period of ,2 h. Of the discharge volume, ,65% to 85% is estimated to be from salt water that infiltrates during high tide episodes. This study highlights the complexity of the dynamic coastal ground water discharge phenomenon and provides insight into the hydraulic mechanisms involved. While there is a general pattern to sandy beach discharge, comparison of results from beaches studied at Cape Cod indicates that the temporal and spatial details of the discharge is very site-specific. [source] Water table and transpiration dynamics in a seasonally inundated Melaleuca quinquenervia forest, north Queensland, AustraliaHYDROLOGICAL PROCESSES, Issue 16 2008David McJannet Abstract Water table fluctuations and transpiration were monitored in a seasonally inundated Melaleuca quinquenervia floodplain forest at Cowley Beach, north Queensland, Australia. Techniques were developed to reconstruct inundation duration and seasonal and inter-annual variability at this site using long-term stream flow data. It was estimated that the median duration of inundation in any year was 75 days with maximum and minimum durations of 167 days and 8 days, respectively. Measurements of individual tree transpiration using heat-pulse techniques showed a strong relationship between tree size and tree water use, which was used for scaling to stand transpiration. Stand transpiration rates were found to be closely tied to atmospheric drivers of evaporation, and transpiration of M. quinquenervia was found to be unaffected by inundation. This ability to transpire during inundation may be due to physiological adaptations of this species. These adaptations are believed to include dynamic root systems that can quickly respond to rising and falling water tables and dense networks of fine apogeotropic roots, which grow on and within the papery bark. Rates of stand transpiration remained low throughout the study (0·46 mm d,1, 164 mm y,1) despite the fact that transpiration was not limited by solar energy inputs or soil moisture deficit. Low stand transpiration was attributed to the low density, stunted nature and small sapwood area of trees at this site. Copyright © 2007 John Wiley & Sons, Ltd. [source] Metamorphism and metamorphic K,Ar ages of the Mesozoic accretionary complex in Northland, New ZealandISLAND ARC, Issue 3 2004Yujiro Nishimura Abstract A southwest dipping Mesozoic accretionary complex, which consists of tectonically imbricated turbiditic mudstone and sandstone, hemipelagic siliceous mudstone, and bedded cherts and basaltic rocks of pelagic origin, is exposed in northern North Island, New Zealand. Interpillow limestone is sometimes contained in the basaltic rocks. The grade of subduction-related metamorphism increases from northeast to southwest, indicating an inverted metamorphic gradient dip. Three metamorphic facies are recognized largely on the basis of mineral parageneses in sedimentary and basaltic rocks: zeolite, prehnite-pumpellyite and pumpellyite-actinolite. From the apparent interplanar spacing d002 data for carbonaceous material, which range from 3.642 to 3.564 Ĺ, the highest grade of metamorphism is considered to have attained only the lowermost grade of the pumpellyite-actinolite facies for which the highest temperature may be approximately 300°C. Metamorphic white mica K,Ar ages are reported for magnetic separates and <2 µm hydraulic elutriation separates from 27 pelitic and semipelitic samples. The age data obtained from elutriation separates are approximately 8 m.y. younger, on average, than those from magnetic separates. The age difference is attributed to the possible admixture of nonequilibrated detrital white mica in the magnetic separates, and the age of the elutriation separates is considered to be the age of metamorphism. If the concept, based on fossil evidence, of the subdivision of the Northland accretionary complex into north and south units is accepted, then the peak age of metamorphism in the north unit is likely to be 180,130 Ma; that is, earliest Middle Jurassic to early Early Cretaceous, whereas that in the south unit is 150,130 Ma; that is, late Late Jurassic to early Early Cretaceous. The age cluster for the north unit correlates with that of the Chrystalls Beach,Taieri Mouth section (uncertain terrane), while the age cluster for the south unit is older than that of the Younger Torlesse Subterrane in the Wellington area, and may be comparable with that of the Nelson and Marlborough areas (Caples and Waipapa terranes). [source] Age and growth of the round stingray Urobatis halleri at Seal Beach, CaliforniaJOURNAL OF FISH BIOLOGY, Issue 3 2008L. F. Hale The age and growth of the round stingray Urobatis halleri was determined using vertebral sections from animals collected at Seal Beach, California from 2002 to 2005. Annual periodicity was validated from U. halleri injected with oxytetracycline and maintained in captivity over a 2 year period (n= 7). The coefficients estimated by the von Bertalanffy growth model were the disc width asymptote (WD,) (286 mm for males and 224 mm for females) and K (0·09 year,1 for males and 0·15 year,1 for females). The age structure of the population consisted of mostly older, mature males and females. Age at maturity was estimated at 3·80 years for females and 3·75 years for males, and the maximum assessed age was 14 years old. Males were more numerous than females throughout the year; however, from May to September, females outnumbered males. The U. halleri age and growth coefficients were comparable to other species in the family Urolophidae. Based on the seasonality and age structure of this population, Seal Beach offers warm-water refuge for U. halleri of reproductive maturity, and the U. halleri at Seal Beach may garner some behavioural thermoregulation benefit. [source] Movement patterns of the round stingray Urobatis halleri(Cooper) near a thermal outfallJOURNAL OF FISH BIOLOGY, Issue 6 2006J. J. Vaudo Fine-scale movements and site fidelity of round stingrays Urobatis halleri at Seal Beach California, U.S.A., were examined using acoustic telemetry. Actively tracked fish generally exhibited limited nearshore movement, with greater distances travelled at night when the tide was ebbing than during the day with ebbing tides. Increases in round stingray activity were associated with increases in ambient temperature. Passively tracked fish showed seasonal patterns in their presence at Seal Beach. Males left Seal Beach during the autumn, returned the following spring, and remained in the area until the following autumn. Females spent far less time at Seal Beach, remaining in the area for a few weeks during June and July. Passively tracked round stingrays were recorded more often in the warm waters of the San Gabriel River mouth (the location of a thermal outfall from an electric-generating station) than adjacent beaches, with fish often returning to Seal Beach after periods of absence. Anthropogenic effects resulting from coastal development may have created environmental conditions (i.e. warmer water and finer sediments) that influence the movements and site fidelity of round stingrays. [source] 83 Comparative analysis of vertically migrating euglena viridis populations in tidal and non-tidal benthic environmentsJOURNAL OF PHYCOLOGY, Issue 2003M.B. KingstonArticle first published online: 12 JAN 200 Benthic populations of Euglena viridis exhibit vertical migration behavior on high energy intertidal beaches and along the sand banks of freshwater streams. This study examines similarities and differences in the migratory behavior and cell morphology of populations of E. viridis inhabiting Scripps Beach, La Jolla, California and Coble Brook, Burlington, North Carolina. The timing of migration was measured by counting the number of cells in samples collected from the sediment surface throughout the day. Sediment cores were extracted and sectioned to determine the vertical distribution of the population. Neutral density filters and opaque canisters were used to shade the substratum to 56%, 22%, 2%, and 0% of incident irradiance (Io) to examine the effect of light on cell morphology and migratory behavior. On intertidal beaches, E. viridis exhibited a tidal rhythm in vertical migration with cells migrating below the sediment surface at night (>15 cm) and during daytime high tides. In this habitat, the upward migration response was enhanced at irradiances lower than 100% Io but cell morphology was not altered by shading. On the banks of freshwater streams, E. viridis exhibited a diurnal migratory rhythm with both tear-drop and spherical morphologies observed throughout the day. The population was most concentrated at the surface around solar noon and at night it was located between 1 and 2 cm below the surface. Shading did not enhance upward migration but it did affect cell morphology. These results will be interpreted in the context of the dominant selection pressures in each environment. [source] Anaphylactic Reactions on the Beach: A Cause for Concern?JOURNAL OF TRAVEL MEDICINE, Issue 5 2009Ricardo J. José No abstract is available for this article. [source] Anaphylactic Reactions on the Beach: A Cause for Concern?JOURNAL OF TRAVEL MEDICINE, Issue 2 2009Alexander D. Karatzanis MD Background The commonest causes of anaphylaxis include hymenoptera bites, high-risk food, exercise, and jellyfish bites and may often be encountered on the beach. Therefore, millions of visitors at popular touristic locations are exposed to increased risk of anaphylactic reactions every year. At least 35 cases of acute allergic reactions requiring medical attention took place on the beaches of Crete, Greece during the previous summer. Objective To evaluate the level of training of lifeguards working on the beaches of the island of Crete, Greece, with regard to emergency management of anaphylaxis as well as to assess the sufficiency of medical equipment that lifeguards possess to treat an anaphylactic reaction. Methods A questionnaire was prepared by the authors and administered to 50 lifeguards working on various beaches of Crete. Queries included the definition of anaphylaxis, proper medical treatment, and the existence or not and composition of an emergency kit with regard to the management of acute allergic reactions. Results Our series consisted of 50 lifeguards, 39 (78%) male and 11 female (22%). Although 41 (80%) lifeguards were aware of an acceptable definition of anaphylaxis, no one knew that epinephrine is the first-choice treatment, and 32 (60%) lifeguards replied that steroids should be used for emergency treatment. Additionally, no one possessed an emergency kit that would qualify for management of acute allergic reactions. Conclusions The beach should be considered as a high-risk place for the appearance of anaphylactic reactions. Lifeguards who would be the first trained personnel to encounter this condition should be sufficiently trained and equipped for emergency treatment. Our department is currently introducing a training program to local authorities for the proper training and equipping of lifeguards in the island of Crete. [source] Abundance, Tidal Movement, Population Structure and Burrowing Rate of Emerita analoga (Anomura, Hippidae) at a Dissipative and a Reflective Sandy Beach in South Central ChileMARINE ECOLOGY, Issue 2 2000Eduardo Jaramillo Abstract. To evaluate the effects of beach morphodynamics upon the abundance, tidal movement, population structure and burrowing rate of the crab Emerita analoga (Stimpson) (Anomura, Hippidae) we sampled two beaches in south central Chile (ca. 42° S), Mar Brava and Ahui with dissipative and reflective characteristics, respectively. The swash zone at the dissipative beach was 5,,,6 times wider than that of the reflective beach. A at the dissipative beach, upwash speeds were higher and the number of effluent line crossings were lower by more than an order of magnitude. To examine the tidal movement of E. analoga, we collected crabs from 5 to 6 tidal levels of each beach every 2 h across 12 h of the tidal cycle. The intertidal distribution of crabs differed between beaches; i. e., at the dissipative beach they were primarily located at the swash zone, while at the reflective beach they were mostly located at the low tide level and shallow subtidal. The change in position of crabs was pronounced across the tidal cycle at the dissipative beach (Mar Brava), with most of the animals remaining in the active swash zone. Body size data were used to construct size frequency distributions for each population. Crabs from the dissipative beach reached larger sizes than those at the reflective beach. Sediments were coarser at the latter versus the former beach. Crabs burrowed at similar rates in the sand from both beaches, a result which supports the idea that E. analoga is a "sediment generalist" capable of burrowing successfully in a wide range of sediment types. This characteristic is likely a key to the broad success of this species on the full range of beach morphodynamic types along the coasts of South and North America. [source] THREE MASS STRANDINGS OF SPERM WHALES (PHYSETER MACROCEPHALUS) IN SOUTHERN AUSTRALIAN WATERSMARINE MAMMAL SCIENCE, Issue 3 2002Karen Evans Abstract One hundred and fifteen sperm whales (97 female, 15 male, 3 unknown sex) were involved in three mass stranding events during the month of February 1998 along the west and northwest coastlines of Tasmania, Australia. Sixty-six of these whales stranded at Ocean Beach, Strahan; 35 at Greens Beach, Marrawah; and 11 at Black River Beach, Stanley. The remaining whales stranded singly along the coastline. Three mass strandings of this species in such close temporal proximity have not been reported in this area before, and this is the first time that data have been comprehensively collected from complete or near-complete groups of sperm whales from Tasmanian waters. Adult females dominated the three stranding groups. Total lengths ranged from 417 to 1,200 cm and ages ranged from 0.75 to 64 yr. Four females were lactating and four fetuses were found amongst the groups. Stomach contents were dominated by pelagic cephalopods. [source] The Bassian Isthmus and the major ocean currents of southeast Australia influence the phylogeography and population structure of a southern Australian intertidal barnacle Catomerus polymerus (Darwin)MOLECULAR ECOLOGY, Issue 8 2008KATHERINE L. YORK Abstract Southern Australia is currently divided into three marine biogeographical provinces based on faunal distributions and physical parameters. These regions indicate eastern and western distributions, with an overlap occurring in the Bass Strait in Victoria. However, studies indicate that the boundaries of these provinces vary depending on the species being examined, and in particular on the mode of development employed by that species, be they direct developers or planktonic larvae dispersers. Mitochondrial DNA sequence analysis of the surf barnacle Catomerus polymerus in southern Australia revealed an east,west phylogeographical split involving two highly divergent clades (cytochrome oxidase I 3.5 ± 0.76%, control region 6.7 ± 0.65%), with almost no geographical overlap. Spatial genetic structure was not detected within either clade, indicative of a relatively long-lived planktonic larval phase. Five microsatellite loci indicated that C. polymerus populations exhibit relatively high levels of genetic divergence, and fall into four subregions: eastern Australia, central Victoria, western Victoria and Tasmania, and South Australia. FST values between eastern Australia (from the eastern mitochondrial DNA clade) and the remaining three subregions ranged from 0.038 to 0.159, with other analyses indicating isolation by distance between the subregions of western mitochondrial origin. We suggest that the east,west division is indicative of allopatric divergence resulting from the emergence of the Bassian land-bridge during glacial maxima, preventing gene flow between these two lineages. Subsequently, contemporary ecological conditions, namely the East Australian, Leeuwin, and Zeehan currents and the geographical disjunctions at the Coorong and Ninety Mile Beach are most likely responsible for the four subregions indicated by the microsatellite data. [source] Multiple paternity in loggerhead turtle (Caretta caretta) nests on Melbourne Beach, Florida: a microsatellite analysisMOLECULAR ECOLOGY, Issue 2 2002M. K. Moore Abstract Many aspects of sea turtle biology are difficult to measure in these enigmatic migratory species, and this lack of knowledge continues to hamper conservation efforts. The first study of paternity in a sea turtle species used allozyme analysis to suggest multiple paternity in loggerhead turtle (Caretta caretta) clutches in Australia. Subsequent studies indicated that the frequency of multiple paternity varies from species to species and perhaps location to location. This study examined fine-scale population structure and paternal contribution to loggerhead clutches on Melbourne Beach, FL, USA using microsatellite markers. Mothers and offspring from 70 nests collected at two locations were analysed using two to four polymorphic microsatellite loci. Fine-scale population differentiation was not evident between the sampled locations, separated by 8 km. Multiple paternity was common in loggerhead nests on Melbourne Beach; 22 of 70 clutches had more than one father, and six had more than two fathers. This is the first time that more than two fathers have been detected for offspring in individual sea turtle nests. Paternal genotypes could not be assigned with confidence in clutches with more than two fathers, leaving the question of male philopatry unanswered. Given the high incidence of multiple paternity, we conclude that males are not a limiting resource for this central Florida nesting aggregate. [source] Polymorphic microsatellite loci in Plantago lanceolataMOLECULAR ECOLOGY RESOURCES, Issue 1 2003Marie L. Hale Abstract The genus Plantago is particularly interesting for evolutionary studies because of its wide range of mating systems. We have developed primers for five highly polymorphic microsatellite loci isolated from P. lanceolata. All five loci amplified and were polymorphic in the two populations examined, Lowsteads Beach in the United Kingdom and Duke in the United States. These new markers will allow a comparison of population structure between the outcrossing species P. lanceolata, and the highly selfing species P. major. [source] Symposia Focus; Technical Director; Annual Election; ASNE Day' 05 in Virginia BeachNAVAL ENGINEERS JOURNAL, Issue 1 2005RADM Dave Sargent USN (Ret.) No abstract is available for this article. [source] Partnership Between an Educational Institution and a Healthcare Agency,Lessons Learned: Part INURSING FORUM, Issue 3 2009Loucine M. Huckabay RN PURPOSE., The purpose of this paper is to provide a model of a partnership program between a major educational institution and a large community medical center that has become a win,win situation for both, which enabled the former to double its undergraduate nursing (BSN) program when it was on the verge of reducing enrollments by 33% because of repeated financial cuts, and a healthcare agency (HCA) to find a creative way of hiring BSN-educated registered nurses in perpetuity, thus reducing their $2 million a month recruitment expenses. PROCESS., This was a 5-year, $15 million partnership between California State University, Long Beach, School of Nursing and Long Beach Memorial Medical Center/Miller Children's Hospital. The HCA contributed the $10 million in funds and in in-kind contributions in the form of facilities and adjunct clinical professors, and the university contributed the $5 million, all in in-kind contribution by doubling the lecture classes without additional cost. The project started in the spring of 2004. CONCLUSION., To date, eight groups have graduated from this program for a total of 288 additional BSN graduates. Retention rate has been a minimum of 95%. Over 95% of the graduates have been hired by the participating HCA. Indeed, it has been a win,win situation for both. [source] Sir Michael Hicks Beach and Conservative Politics 1880,1888,PARLIAMENTARY HISTORY, Issue 3 2000LEIGH MICHAEL POWELL First page of article [source] Seasonal and spatial patterns of population density in the marine macroalga Mazzaella splendens (Gigartinales, Rhodophyta)PHYCOLOGICAL RESEARCH, Issue 1 2006Leonard James Dyck SUMMARY Insight into demographic processes that operate at larger spatial scales can be achieved through studying local populations when a particular species of interest is examined over time, by many investigators, in a variety of locations. On the west coast of North America, Mazzaella splendens (Setchell et Gardner) Fredericq is such a species of interest. A synthesis of local demographic studies of M. splendens from the late 1960s to the present reveals a pattern that is potentially common to the larger natural populations. This is the pattern: population density is high in summer and low in winter for both alternate free-living life history phases of M. splendens. The magnitude of this seasonal change decreases in increasingly wave-exposed habitats. In wave-sheltered habitats there is a seasonal alternation from summer haploid to winter diploid dominance. This alternation gradually changes to constant diploid dominance as wave exposure in the habitat increases. Changes in population density are primarily a function of appearances and disappearances of perennating basal crusts (genets), as modules are produced or lost, rather than differential module production by genets of one phase over those of the other. To test the generality of this pattern, we examined seasonal changes in density, in local populations of M. splendens, in both a wave-sheltered and a wave-exposed habitat at Second Beach, Barkley Sound. Greater seasonal fluctuation in population density at wave-sheltered, compared to wave-exposed habitats is supported as a pattern potentially common to the natural populations of M. splendens. A change from summer haploid dominance in wave-sheltered areas to summer diploid dominance in wave-exposed areas is similarly supported. All changes in population density were the result of appearances and disappearances of genets rather than differential module production by haploid versus diploid basal crusts, also consistent with previous observations. A seasonal alternation in phase dominance, however, was absent from the wave-sheltered site at Second Beach, Barkley Sound for 3 consecutive years. Seasonal alternation in phase dominance of M. splendens appears dependent on local conditions and is not common to all natural populations. [source] Meeting report: consensus from the first and second Global Workshops in Melanoma November 19,20, 2008PIGMENT CELL & MELANOMA RESEARCH, Issue 5 2009Sanjiv S. Agarwala This overview of the current state of melanoma research and treatment and directions for moving forward represents the consensus of discussions between expert panelists at the First and Second Global Workshops on Melanoma held in Fajardo, Peurto Rico on November 30,December 1, 2007 and Clearwater Beach, Florida on November 19,20, 2008. [source] Proteomics Data Collection , 3rd ProDaC Workshop April 22nd 2008, Toledo, SpainPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 20 2008Martin Eisenacher Abstract The "Coordination Action" ProDaC (Proteomics Data Collection) , funded by the EU within the 6th framework programme , was created to support the dissemination, utilization and publication of proteomics data. Within this international consortium, standards are developed and maintained to support extensive data collection by the proteomics community. An important part of ProDaC are workshops organized on a regular basis (two per year) to allow discussions and communication between the ProDaC partners and to report on the progress of the project. The kick-off meeting took place in October 2006 in Long Beach, CA, USA. The 1st ProDaC workshop was held in Lyon, France (April 2007) and the 2nd in Seoul, Korea in October 2007. ProDaC organized the 3rd ProDaC workshop at the Beatriz Hotel, Toledo, on 22nd April, 2008, directly before the HUPO - PSI spring meeting (Human Proteome Organisation - Proteomics Standards Initiative). The work package coordinators presented talks about the progress achieved during the past six months. Additionally four external speakers presented their work on data conversion and data repositories. The concluding discussion session was chaired by the Journal's representative. [source] Assessing the Effectiveness of Executive Order 12898: Environmental Justice for All?PUBLIC ADMINISTRATION REVIEW, Issue 6 2002Celeste Murphy, Greene This article examines several federal and state laws, such as the Worker Protection Standards and the Florida Pesticide Law, to determine whether the goals of these laws are being achieved in the State of Florida. A survey based on questions pertaining to various laws was used to gather data on farm workers in three South Florida counties. Face,to,face interviews were conducted with farm workers in Palm Beach and Indian River counties, Florida, in 1997 and in Collier County, Florida, in 1999. Overall, the findings indicate that farm workers in South Florida have been exposed to pesticides through direct or indirect spraying. The findings of the study reveal that federal and state laws,currently in place to protect the workers from pesticide exposure,are not effectively implemented, and farm workers are uninformed of the laws that exist to protect them from pesticide exposure. The study concludes with policy recommendations that will improve the implementation and enforcement of the current laws, which are designed to protect farm workers from pesticide exposure. [source] "This Is Active Learning": Theories of Language, Learning, and Social Relations in the Transmission of Khmer LiteracyANTHROPOLOGY & EDUCATION QUARTERLY, Issue 1 2003Assistant Professor Susan Needham This article examines the role language ideologies played in the changing instructional and social organization of Khmer literacy classes in Long Beach, California. Language and language use in classrooms have been carefully examined over the years, but analysis of how language attitudes influence pedagogical theory and practice has been largely neglected. This article reveals one way in which language ideologies engage with local theories of learning to shape not only pedagogies informing instruction but also social relations within classes. [source] Survival and growth responses of eight Everglades tree species along an experimental hydrological gradient on two tree island typesAPPLIED VEGETATION SCIENCE, Issue 4 2010Susana L. Stoffella Abstract Questions: How are the early survival and growth of seedlings of Everglades tree species planted in an experimental setting on artificial tree islands affected by hydrology and substrate type? What are the implications of these responses for broader tree island restoration efforts? Location: Loxahatchee Impoundment Landscape Assessment (LILA), Boynton Beach, Florida, USA. Methods: An experiment was designed to test hydrological and substrate effects on seedling growth and survivorship. Two islands , a peat and a limestone-core island representing two major types found in the Everglades , were constructed in four macrocosms. A mixture of eight tree species was planted on each island in March of 2006 and 2007. Survival and height growth of seedlings planted in 2006 were assessed periodically during the next two and a half years. Results: Survival and growth improved with increasing elevation on both tree island substrate types. Seedlings' survival and growth responses along a moisture gradient matched species distributions along natural hydrological gradients in the Everglades. The effect of substrate on seedling performance showed higher survival of most species on the limestone tree islands, and faster growth on their peat-based counterparts. Conclusions: The present results could have profound implications for restoration of forests on existing landforms and artificial creation of tree islands. Knowledge of species tolerance to flooding and responses to different edaphic conditions present in wetlands is important in selecting suitable species to plant on restored tree islands [source] Effects of Coastal Lighting on Foraging Behaviorof Beach MiceCONSERVATION BIOLOGY, Issue 5 2004BRITTANY L. BIRD comportamiento de forrajeo; iluminación artificial; polución por luz; ratones de playa (Peromyscus polionotus leucocephalus) Abstract:,Introduction of artificial light into wildlife habitat represents a rapidly expanding form of human encroachment, particularly in coastal systems. Light pollution alters the behavior of sea turtles during nesting; therefore, long-wavelength lights,low-pressure sodium vapor and bug lights,that minimize impacts on turtles are required for beach lighting in Florida (U.S.A.). We investigated the effects of these two kinds of lights on the foraging behavior of Santa Rosa beach mice ( Peromyscus polionotus leucocephalus). We compared patch use and giving-up densities of mice for experimental food patches established along a gradient of artificial light in the field. Mice exploited fewer food patches near both types of artificial light than in areas with little light and harvested fewer seeds within patches near bug lights. Our results show that artificial light affects the behavior of terrestrial species in coastal areas and that light pollution deserves greater consideration in conservation planning. Resumen:,La introducción de luz artificial al hábitat de vida silvestre representa una forma de intrusión humana que se expande rápidamente, particularmente en sistemas costeros. Durante la anidación, la polución por luz altera el comportamiento de tortugas marinas; por tanto, para la iluminación de playas en Florida (E. U. A) se requieren luces de longitud de onda larga , luces de vapor de sodio de baja presión y contra insectos , que minimizan impactos sobre las tortugas. Investigamos los efectos de estos dos tipos de luces sobre el comportamiento de forrajeo de ratones de playa de Santa Rosa ( Peromyscus polionotus leucocephalus). Comparamos el uso de parches y las densidades de rendición de ratones en parches alimenticios experimentales establecidos a lo largo de un gradiente de luz artificial en el campo. Los ratones utilizaron menos parches de forrajeo cercanos a ambos tipos de luz artificial que en áreas con poca iluminación y cosecharon menos semillas en parches cercanos a luces contra insectos. Nuestros resultados muestran que la luz artificial afecta el comportamiento de especies terrestres en áreas costeras y que la polución por luz merece mayor consideración en la planificación de la conservación. [source] Centennial odysseys: longest way roundCRITICAL QUARTERLY, Issue 1-2 2005Michael Wood This essay explores the questions about the writing of fiction and the use of metaphor posed by J. M. Coetzee's 2003 work Elizabeth Costello, and finds an answer to these eloquent and disturbing queries in Mr Bloom's reflections on the beach and in the cemetery, instances of Joyce's acceptance of the radical presence of the figurative at the heart of the real. [source] Backshore coarsening processes triggered by wave-induced sand transport: the critical role of storm events,EARTH SURFACE PROCESSES AND LANDFORMS, Issue 11 2010Keiko Udo Abstract Spatial backshore processes were investigated through field observations of topography and median sand grain size at a sandy beach facing the Pacific Ocean in Japan. A comparison of the backshore profile and cross-shore distribution of the median sand grain size in 1999 and 2004 revealed an unusual sedimentary process in which sand was coarsened in a depositional area in the 5-year period, although sediment is generally coarsened in erosional areas. In support of these observations, monthly spatial field analyses carried out in 2004 demonstrated a remarkable backshore coarsening process triggered by sedimentation in the seaward part of the backshore during a storm event. In order to elucidate mechanisms involved in the backshore coarsening process, thresholds of movable sand grain size under wave and wind actions (a uniform parameter for both these cases) in the onshore and offshore directions were estimated using wave, tide, and wind data. The cross-shore distributions of the estimated thresholds provided reasonable values and demonstrated a coarsening mechanism involving the intermediate zone around the shoreline under alternating wave and wind actions as a result of which coarse sand was transported toward the seaward part of the backshore by large waves during storms and then toward the landward part by strong onshore winds. The 5-year backshore coarsening is most certainly explained by repetition of short-term coarsening mechanisms caused by wave-induced sand transport occurring from the nearshore to the intermediate zone. Copyright © 2010 John Wiley & Sons, Ltd [source] | |||||||||||||||||||||||||||||||||||||||||||||||||