Twelve-year acorn yield in Southern Appalachian Oaks

Treesearch

Donald E. Beck

1977-01-01

A 12-year sample from Southern Appalachian oak stands showed acorns to be a valuable though inconsistent source of wildlife food. At least moderate amounts of acorns were produced in 9 of the years, with 4 years being exceptionally good. In 3 of the years, acorn production was very low. There were distinct differences in the production of acorns by the five species...

Response of insects to damaged and undamaged germinating acorns

Treesearch

Jimmy R. Galford; Deloris Weiss-Cottrill

1991-01-01

Damaged germinating northern red oak, Quercus rubra L., acorns in pitfall traps were significantly more attractive to two species of acorn insects than undamaged germinating acorns. Significantly more adults of the weevil Conotrachelus posticatus ohe em an and the sap beetle Stelidota octomaculata (Say) were caught in traps containing germinating acorns cut into halves...

Millipede damage to germinating acorns of northern red oak

Treesearch

Jimmy R. Galford; L. R. Auchmoody; Russell S. Walters; H. Clay. Smith; H. Clay. Smith

1992-01-01

Millipedes have not been reported as pests of germinating acorns. Studies in Pennsylvania on the impact of insects on northern red (Quercus rubra L. seedling establishment revealed that the millipede Ptyoiulus impressus (Say) damaged the radicles of germinating acorns. Up to 17 percent of the acorn radicles in areas with heavy acorn crops were damaged in 1'991....

Sweep-net sampling acorns in forested wetlands

Treesearch

Mitch D. Weegman; Richard M. Kaminski; Guiming Wang; Michael L. Schummer; Andrew W. Ezell; Theodor D. Leininger

2010-01-01

We are unaware of any previous studies to evaluate using a sweep net to estimate abundance of red oak acorns (Quercus spp.) after they fall from tree crowns, sink to the ground in flooded bottomlands (i.e., sound acorns), and become potential food for animals or propagules for seedlings. We placed known numbers of white-painted red oak acorns of 3 size classes and used...

Mechanical Limits to Size in Wave-Swept Organisms.

DTIC Science & Technology

1983-11-10

complanata, the probability of destruction and the size- specific increase in the risk of destruction are both substantial. It is conjectured that the...barnacle, Semibalanus cariosus) the size-specific increment in the risk of destruction is small and the size limits imposed on these organisms are...constructed here provides an experimental approach to examining many potential effects of environmental stress caused by flowing water. For example, these

Acorn storage alternatives tested on Oregon white oak

Treesearch

Warren D. Devine; Constance A. Harrington; Joseph M. Kraft

2010-01-01

We assessed various combinations of storage factors: bag type, temperature, duration, and antifungal pre-storage treatments for white oak acorn storage, using Oregon white oak (Quercus garryana Douglas ex Hook. [Fagaceae]) acorns from 7 seed sources. Acorn viability remained high (84%), even after 2 y of refrigerated storage, but the majority of...

Water Uptake and Germination of Red Oak Acorns

Treesearch

F. T. Bonner

1968-01-01

When pericarps were intact, water was absorbed by Nuttall, pin, cherrybark, and northern red oak acorns, mainly through the vascular openings of the cup scar. Uptake through the pericarp was greater for acorns with a thin waxy coating on the pericarp than for acorns with a heavy waxy coating. Splitting or removing the pericarp greatly speeded uptake. Osmotically...

Acorn fall and weeviling in a northern red oak seedling orchard

Treesearch

Daniel R. Miller; Scott E. Schlarbaum

2005-01-01

In 2000, we determined levels of damage by acorn weevils (Curculio spp.) and patterns of acorn fall in a northern red oak (Quercus rubra L.) seedling orchard in eastern Tennessee. The mean (±SE) production of acorns among 43 selected trees was 5,930 ± 586 acorns per tree with a maximum production level of 16,969 acorns for one tree...

Insects that damage white oak acorns

Treesearch

Lester P. Gibson; Lester P. Gibson

1972-01-01

To grow oak trees--either in forests or for shade trees--crops of good acorns are needed. Yet in some places and at some times, acorn crops are destroyed or badly damaged by insects. To prevent this we need to know, first of all, which insects do the damage.

Sowing pregerminated northern red oak acorns

Treesearch

Richard M. Godman; Gilbert A. Mattson

1992-01-01

Northern red oak is extremely difficult to regenerate, although it has produced good acorn crops nearly half of the last 32 years in northern Wisconsin. Field trials have shown that for successful seeding, you must protect acorns from predation by wildlife and sow them when temperatures are most favorable for germination.

A rapid hard-mast index from acorn presence-absence tallies

Treesearch

Cathryn H. Greenberg; Gordon S. Warburton

2007-01-01

We used 21 years of acorn data from visual surveys of oak (Quercus spp.) trees (n ¼ 20,113) conducted in western North Carolina, USA, to develop predictive equations for hard-mast indices (HMIs) based on the proportion of trees bearing acorns (PBA). We calculated PBA using visual estimates of the percentage of oak crown with acorns (PCA), assigning acorn presence if...

Acorn production in northern red oak stands in northwestern Pennsylvania

Treesearch

L. R. Auchmoody; H. Clay Smith; Russell S. Walters

1993-01-01

Northern red oak acorn production was measured in 21 maturing stands on good sites in northwestern Pennsylvania. The number of acorns produced per acre varied from a low of 7,000 to nearly 273,000. Acorns were produced in all years. In no year was there consistently good acorn production at all areas, nor was there a good crop for more than two consecutive years at any...

Planting northern red oak acorns: is size and planting depth important?

Treesearch

L.R. Auchmoody; H. Clay Smith; Russell S. Walters

1994-01-01

A study was conducted in northern Pennsylvania to determine whether predation by small mammals and insects is related to the size of red oak acorns. Three sizes of acorns were used aiong with two planting techniques and three levels of overstory shading. Three-year results indicated that acorn size is not a factor in mammal and insect predation. Acorn size did not...

Characterization of the cork oak transcriptome dynamics during acorn development.

PubMed

Miguel, Andreia; de Vega-Bartol, José; Marum, Liliana; Chaves, Inês; Santo, Tatiana; Leitão, José; Varela, Maria Carolina; Miguel, Célia M

2015-06-25

Cork oak (Quercus suber L.) has a natural distribution across western Mediterranean regions and is a keystone forest tree species in these ecosystems. The fruiting phase is especially critical for its regeneration but the molecular mechanisms underlying the biochemical and physiological changes during cork oak acorn development are poorly understood. In this study, the transcriptome of the cork oak acorn, including the seed, was characterized in five stages of development, from early development to acorn maturation, to identify the dominant processes in each stage and reveal transcripts with important functions in gene expression regulation and response to water. A total of 80,357 expressed sequence tags (ESTs) were de novo assembled from RNA-Seq libraries representative of the several acorn developmental stages. Approximately 7.6 % of the total number of transcripts present in Q. suber transcriptome was identified as acorn specific. The analysis of expression profiles during development returned 2,285 differentially expressed (DE) transcripts, which were clustered into six groups. The stage of development corresponding to the mature acorn exhibited an expression profile markedly different from other stages. Approximately 22 % of the DE transcripts putatively code for transcription factors (TF) or transcriptional regulators, and were found almost equally distributed among the several expression profile clusters, highlighting their major roles in controlling the whole developmental process. On the other hand, carbohydrate metabolism, the biological pathway most represented during acorn development, was especially prevalent in mid to late stages as evidenced by enrichment analysis. We further show that genes related to response to water, water deprivation and transport were mostly represented during the early (S2) and the last stage (S8) of acorn development, when tolerance to water desiccation is possibly critical for acorn viability. To our knowledge this work

Insect and Disease Impacts on Blue Oak Acorns and Seedlings

Treesearch

Tedmund J. Swiecki; Elizabeth A. Bernhardt; Richard A. Arnold

1991-01-01

We studied the impacts of diseases and arthropods on acorns and naturally occurring seedlings of blue oak, Quercus douglasii, in northern California. Damage levels were always significantly higher in acorns collected from the ground than those picked from the tree. Accurate assessments of damage levels could only be made by dissecting acorns, since...

Effect of barnacle fouling on ship resistance and powering.

PubMed

Demirel, Yigit Kemal; Uzun, Dogancan; Zhang, Yansheng; Fang, Ho-Chun; Day, Alexander H; Turan, Osman

2017-11-01

Predictions of added resistance and the effective power of ships were made for varying barnacle fouling conditions. A series of towing tests was carried out using flat plates covered with artificial barnacles. The tests were designed to allow the examination of the effects of barnacle height and percentage coverage on the resistance and effective power of ships. The drag coefficients and roughness function values were evaluated for the flat plates. The roughness effects of the fouling conditions on the ships' frictional resistances were predicted. Added resistance diagrams were then plotted using these predictions, and powering penalties for these ships were calculated using the diagrams generated. The results indicate that the effect of barnacle size is significant, since a 10% coverage of barnacles each 5 mm in height caused a similar level of added power requirements to a 50% coverage of barnacles each 1.25 mm in height.

Individual variation in acorn production by five species of southern Appalachian oaks

Treesearch

Cathryn H. Greenberg

2000-01-01

Acorns are an important wildlife food resource and seed source for oak regeneration. Most acorn production studies note wide and consistent differences in acorn productivity among individuals, but none clearly demonstrate determinants of productivity. Acorn production by black, northern red, scarlet, chestnut, and white oak was measured from 1993 to 1997 in the...

Modern Antarctic acorn worms form tubes.

PubMed

Halanych, Kenneth M; Cannon, Johanna T; Mahon, Andrew R; Swalla, Billie J; Smith, Craig R

2013-01-01

Acorn worms, or enteropneusts, are vermiform hemichordates that occupy an important position in deuterostome phylogeny. Allied to pterobranch hemichordates, small colonial tube dwellers, modern enteropneusts were thought to be tubeless. However, understanding of hemichordate diversity is poor, as evidenced by absence of reports from some oceanic regions and recent descriptions of large epibenthic deep-water enteropneusts, Torquaratoridae. Here we show, based on expeditions to Antarctica, that some acorn worms produce conspicuous tubes that persist for days. Interestingly, recent fossil descriptions show a Middle Cambrian acorn worm lived in tubes, leading to speculation that these fossils may have been pterobranch forbearers. Our discovery provides the alternative interpretation that these fossils are similar to modern-day torquaratorids and that some behaviours have been conserved for over 500 million years. Moreover, the frequency of Antarctic enteropneusts observed attests to our limited knowledge of Antarctic marine ecosystems, and strengthens hypotheses relating more northern deep-sea fauna to Antarctic shelf fauna.

Barnacle cement: a polymerization model based on evolutionary concepts

PubMed Central

Dickinson, Gary H.; Vega, Irving E.; Wahl, Kathryn J.; Orihuela, Beatriz; Beyley, Veronica; Rodriguez, Eva N.; Everett, Richard K.; Bonaventura, Joseph; Rittschof, Daniel

2009-01-01

Summary Enzymes and biochemical mechanisms essential to survival are under extreme selective pressure and are highly conserved through evolutionary time. We applied this evolutionary concept to barnacle cement polymerization, a process critical to barnacle fitness that involves aggregation and cross-linking of proteins. The biochemical mechanisms of cement polymerization remain largely unknown. We hypothesized that this process is biochemically similar to blood clotting, a critical physiological response that is also based on aggregation and cross-linking of proteins. Like key elements of vertebrate and invertebrate blood clotting, barnacle cement polymerization was shown to involve proteolytic activation of enzymes and structural precursors, transglutaminase cross-linking and assembly of fibrous proteins. Proteolytic activation of structural proteins maximizes the potential for bonding interactions with other proteins and with the surface. Transglutaminase cross-linking reinforces cement integrity. Remarkably, epitopes and sequences homologous to bovine trypsin and human transglutaminase were identified in barnacle cement with tandem mass spectrometry and/or western blotting. Akin to blood clotting, the peptides generated during proteolytic activation functioned as signal molecules, linking a molecular level event (protein aggregation) to a behavioral response (barnacle larval settlement). Our results draw attention to a highly conserved protein polymerization mechanism and shed light on a long-standing biochemical puzzle. We suggest that barnacle cement polymerization is a specialized form of wound healing. The polymerization mechanism common between barnacle cement and blood may be a theme for many marine animal glues. PMID:19837892

A mono harvest of California black oak acorns

Treesearch

Jonathan W. Long; Ron W. Goode

2017-01-01

In about 1925 or 1926, Margaret Baty, a tribal member of Big Sandy Rancheria, displayed a collection of acorns from California black oak (Quercus kelloggii, wi-yap' in Mono) and an acorn cooking basket. This photograph, taken by George Holt and courtesy of the Flegal Collection of the Jesse Peter Museum at Santa Rosa Junior College,...

Factors affecting acorn production and germination and early growth of seedlings and seedling sprouts

Treesearch

David F. Olson; Stephen G. Boyce

1971-01-01

Acorn production is extremely variable and unpredictable. Flowering is copious, but many climatic factors influence acorn development from initiation of flowers to acorn maturity. Acorns are consumed by birds, animals, insects, and microorganisms. The establishment of seedlings is more closely related to favorable site factors than to size of crops. A majority of oaks...

Evaluation of an approach to improve acorn production during thinning

Treesearch

W.E. Drake

1991-01-01

Large poletimber size, mixed oak (Quercus spp.) stands in Centre County, Pennsylvania were thinned to determine whether acorn production could be improved by retaining the best acorn producing oaks as compared with conventional thinning practices.

Variable Acorn Crops: Responses of White-Tailed Deer and Other Mast Consumers

Treesearch

William J. McShea; Georg Schwede

1993-01-01

We examined movements and behavior of female white-tailed deer (Odocoileus virginianus) relative to the acorn mast-fall from 1986 through 1989 in a mature deciduous forest in Front Royal, Virginia. Ten white-tailed deer with radiotransmitters increased their home range to incorporate acorn-producing areas during mast-fall. Consumption of acorns by...

Context dependence of acorn handling by the Algerian mouse (Mus spretus)

NASA Astrophysics Data System (ADS)

Gallego, D.; Morán-López, T.; Torre, I.; Navarro-Castilla, Á.; Barja, I.; Díaz, M.

2017-10-01

Perceived predation risk and competition for acorns are expected to affect scatter-hoarding decisions by Algerian mice (Mus spretus). We manipulated both factors by means of predator fecal scents and ungulate exclosures. We hypothesized that high-risk perception and ungulate presence would promote acorn dispersal. In the former case, it would stimulate acorn mobilization to safe microhabitats rather than in situ consumption. In the latter, increased competition for acorns would promote their storage for later consumption. We also expected that mice would adapt their foraging behavior to previous experience modulating the strength of these effects. In the presence of ungulates, mice focused their foraging activities on food acquisition at the expenses of vigilant behaviors. However, a more efficient foraging did not entail enhanced dispersal services. Lack of anti-predatory cover in tree surroundings may have deterred mice from transporting seeds outside canopies. Increased risk interacted with previous experience. In control trees (no predator odor), mice confidence increased throughout the night resulting in decreased vigilance and enhanced acorn mobilization rates. In contrast, in risky conditions (trees with predator odor) mice maintained a base-line vigilant behavior. Contrary to our expectations, increased risk did not result in higher acorn mobilization, but the opposite. Again, the scarcity of safe microhabitats for mobilization may have been the underlying cause of this behavior. Our results show that successful acorn dispersal depends, at least partly, on plant-animal relationships that are beyond the oak-rodent mutualism. Thus, any conservation policy aimed at restoring natural regeneration of oaks should take into account the interaction network in which oak-rodent encounters are embedded. In addition, they suggest that mice incorporate direct and indirect cues of risks (habitat structure) through recent experience. A better understanding of this process

Storing Red Oak Acorns

Treesearch

F. T. Bonner

1973-01-01

Cherrybark, Shumard, and water oak acorns can be stored for 3 years or longer if kept at a moisture content of at least 30 percent of fresh weight and at a temperature of 37F. Polyethylene bags are good containers.

Interannual consistency of gross energy in red oak acorns

Treesearch

A.G. Leach; R.M. Kaminski; J.N. Straub; A.W. Ezell; T.S. Hawkins; T.D. Leininger

2013-01-01

Red oak Quercus spp., Subgenus Erythrobalanus acorns are forage for mallards Anas platyrhyncos, wood ducks Aix sponsa, and other wildlife that use bottomland hardwood forests in the southeastern United States. However, annual variation in true metabolizable energy from acorns would affect carrying-capacity estimates of bottomland hardwood forests for wintering ducks....

True metabolizable energy for wood ducks from acorns compared to other waterfowl foods

USGS Publications Warehouse

Kaminski, R.M.; Davis, J.B.; Essig, H.W.; Gerard, P.D.; Reinecke, K.J.

2003-01-01

Acorns of bottomland red oaks (Quercus spp.) are an important food of North American wood ducks (Aix sponsa). Barras et al. (1996) demonstrated that female wood ducks selected willow oak ( Q. phetlos) acorns over other species. We measured true metabolizable energy (TME) derived by captive, wild-strain, adult female wood ducks from acorns of willow oak, water oak (Q. nigra), cherrybark oak (Q. pagoda), and pin oak (Q. patustris) to determine whether female wood ducks' preference for willow oak acorns was related to TME. Estimates of TME within acorn species were relatively precise, yet we did not detect variation in TME among acorn species (P= 0.31 ); hence, we estimated TME across species (2.76 + 0.033 [SE] kcal/g dry mass; n = 34). We concluded that TME apparently did not explain female wood ducks' preference for willow oak acorns and hypothesized that morphological characteristics of willow oak acorns may be proximate cues related to selection by wood ducks. We also summarized known TME estimates for acorns fed to wood ducks and mallards (Anas platyrhynchos), and natural and agricultural foods fed to mallards, northern pintails (A. acura), blue-winged teal (A. discors), and Canada geese (Branta canadensis). We found that acorns and moist-soil plant seeds and tubers provided, on average, about 76% of the TME in agricultural seeds. Thus, bottomland-hardwood and moist-soil habitats have potential to provide significant amounts of dietary energy, as well as greater diversity of foods and nutrients than croplands. Researchers should continue to determine TME of common foods (plant and animal) of waterfowl, and use TME in estimating waterfowl habitat carrying capacity (e.g., Reinecke et al. 1989). Additionally, large-scale, reliable estimates of plant and animal food availability in bottomland-hardwood and moist-soil habitats are needed to evaluate carrying capacity of landscapes important to waterfowl, such as the Mississippi Alluvial Valley (MAV).

Barnacles and gravity

DOE PAGES

Scargill, James H. C.

2017-09-18

Theories with more than one vacuum allow quantum transitions between them, which may proceed via bubble nucleation; theories with more than two vacua posses additional decay modes in which the wall of a bubble may further decay. The instantons which mediate such a process have O(3) symmetry (in four dimensions, rather than the usual O(4) symmetry of homogeneous vacuum decay), and have been called ‘barnacles’; previously they have been studied in flat space, in the thin wall limit, and this paper extends the analysis to include gravity. It is found that there are regions of parameter space in which, givenmore » an initial bubble, barnacles are the favoured subsequent decay process, and that the inclusion of gravity can enlarge this region. The relation to other heterogeneous vacuum decay scenarios, as well as some of the phenomenological implications of barnacles are briefly discussed.« less

Introduction to the symposium--barnacle biology: essential aspects and contemporary approaches.

PubMed

Zardus, John D

2012-09-01

Barnacles have evolved a number of specialized features peculiar for crustaceans: they produce a calcified, external shell; they exhibit sexual strategies involving dioecy and androdioecy; and some have become internal parasites of other Crustacea. The thoroughly sessile habit of adults also belies the highly mobile and complex nature of their larval stages. Given these and other remarkable innovations in their natural history, it is perhaps not surprising that barnacles present a spectrum of opportunities for study. This symposium integrates research on barnacles in the areas of larval biology, biofouling, reproduction, biogeography, speciation, population genetics, ecological genomics, and phylogenetics. Pioneering comparisons are presented of metamorphosis among barnacles from three major lineages. Biofouling is investigated from the perspectives of biochemical and biomechanical mechanisms. Tradeoffs in reproductive specializations are scrutinized through theoretical modeling and empirical validation. Patterns of endemism and diversity are delineated in Australia and intricate species boundaries in the genus Chthamalus are elucidated for the Indo-Pacific. General methodological concerns with population expansion studies in crustaceans are highlighted using barnacle models. Data from the first, draft barnacle genome are employed to examine location-specific selection. Lastly, barnacle evolution is framed in a deep phylogenetic context and hypothetical origins of defined characters are outlined and tested.

Effect of Acorn Planting Depth on Depredation, Emergence, and Survival of Valley and Blue Oak

Treesearch

William D. Tietje; Sherryl L. Nives; Jennifer A. Honig; William H. Weitkamp

1991-01-01

During 1989 in east-central San Luis Obispo County, California, we studied the relationship of valley oak (Quercus lobata) and blue oak (Q. douglasii) acorn planting depth and number of acorns per planting site to acorn depredation, seedling emergence, survival, and height. Acorns were planted at three depths (1.3, 5.1, and 10.2 cm...

Australian barnacles (Cirripedia: Thoracica), distributions and biogeographical affinities.

PubMed

Jones, Diana S

2012-09-01

Currently, 279 barnacle species are recognized in Australia waters. The barnacle fauna of tropical Australia exhibits high species diversity (221), with a high incidence of tropical species (87 Indo-west Pacific [IWP], 16 West Pacific and 65 Indo-Malayan), a low species endemicity (8), and 44 cosmopolitan and 1 Australasian species. Conversely, that of temperate Australia shows lower species diversity (129), with a lower incidence of tropical species (26 IWP, 10 West Pacific and 25 Indo-Malayan), higher species endemicity (23), 37 cosmopolitan, 6 Australasian species, and 3 Australasian/Antarctic species. Distributions corroborate the general patterns demonstrated by the shallow-water biota of northern tropical and southern temperate Australian biogeographic provinces. Tropical and temperate provinces grade into each other in a broad overlap zone along both the western and eastern Australian coasts. This overlap zone is essentially a transitional region, with the gradual replacement of a tropical barnacle fauna in the north by a predominantly temperate barnacle fauna in the south. Both western and eastern Australian coasts are bounded by major poleward-flowing warm currents that have considerable influence on the marine flora and fauna, distributing tropical species of many taxa much farther south than could be predicted by latitude. Currently, 16 barnacle species introduced into Australian waters are identified, although this number may increase in the future due to new port developments and increased shipping arrivals.

Effects of winter flooding on mass and gross energy of bottomland hardwood acorns

Treesearch

Alan G. Leach; Jacob N. Straub; Richard M. Kaminski; Andrew W. Ezell; Tracy S. Hawkins; Theodor D. Leininger

2012-01-01

Decomposition of red oak acorns (Quercus spp.; Section Erythrobalanus) could decrease forage biomass and gross energy (GE) available to wintering ducks from acorns. We estimated changes in mass and GE for 3 species of red oak acorns in flooded and non-flooded bottomland hardwood forests in Mississippi during winter 2009–2010. Mass...

Acorn production and utilization in the Republic of Korea

Treesearch

Shawn Overstreet; Seongmin Choi; Chan-Ryul Park; Dowon Lee; Thomas Gradziel

2015-01-01

Oak acorns have historically provided food for humans and animals in cultures across Asia, North Africa, Europe, and North America. The advent of the twentieth-century saw acorns become marginalized as a food crop in the United States and most of the world, but they have remained a constant part of the cuisine of the Korean Peninsula. Consequently, Korea is often cited...

Insects of bur oak acorns

Treesearch

Lester P. Gibson

1971-01-01

During 1961-1969, the insects found damaging acorns of bur oak, Quercus macrocarpa Michauxii, in their order of importance were the weevils: Curculio pardalis (Chittenden), C. strictus (Casey), C. sulcatulus (Casey), C. iowensis (Casey), C. proboscideus...

Acorn Weevils, Rodents, and Deer All Contribute to Oak-Regeneration Difficulties in Pennsylvania

Treesearch

David A. Marquis; Philip L. Eckert; Benjamin A. Roach

1976-01-01

In parts of Pennsylvania, oak regeneration after harvest cutting or natural disturbances has been very poor. Studies on the Tuscarora State Forest suggest that the primary cause of natural regeneration failure may be a lack of viable acorns; on some sites acorn insects and rodents destroy nearly all acorns, even in good seed years. Artificial regeneration is not...

Northern Red Oak From Acorns to Acorns in 8 Years or Less

Treesearch

Paul P. Kormanik; Shi-Jean S. Sung; Taryn Kormanik; Tom Tibbs; Stanley J. Zarnoch

2004-01-01

The intrinsic factors affecting acorn production in oak trees need further study. Common knowledge holds that an oak requires a minimum number of years to begin flowering, with 30 to 50 most frequently reported. Recently, the Institute of Tree Root Biology has been studying the development of northern red oak ( L.) in the nursery and in...

Can incubators work in Africa? Acorn Technologies and the entrepreneur-centric model.

PubMed

Chakma, Justin; Masum, Hassan; Singer, Peter A

2010-12-13

Incubators are organizations that support the growth of new and typically technology-based enterprises, by providing business support services that bring together human and financial capital. Although the traditional role of incubators has been for economic development, they may also be a useful policy lever to tackle global health, by fostering the development and delivery of local health innovation.Given its high disease burden, life sciences incubators hold particular potential for Africa. As the most industrially advanced African nation, South Africa serves as a litmus test for identifying effective incubator policies. The case study method was used to illustrate how one such publicly funded incubator founded in 2002, Acorn Technologies, helped to catalyze local health product innovation. Acorn helped to support twelve biomedical device firms. One of them, Real World Diagnostics, was founded by a trainee from Acorn's innovative internship program (Hellfire). It developed rapid strip diagnostic tests for locally prevalent diseases including schistosomiasis and HIV, and reported $2 million (USD) in revenue in 2009.Acorn achieved this success by operating as a non-profit virtual incubator with little physical infrastructure. Employing a virtual model in combination with stringent selection criteria of capital efficiency for clients proved to be effective in reducing its own fixed costs. Acorn focused on entrepreneurship training and networking, both critical at an early stage in an environment dominated by multinational biomedical device companies.Acorn and its clients learned that employing a cross-subsidy business model allowed one to generate royalty revenue through imports to subsidize R&D for local diseases. However, funding constraints and government expectations for rapid self-sustainability forced Acorn to merge with its sister biotechnology incubator in 2009. A key to Acorn's achievements was identifying entrepreneurs with technologies with health and

White oak seedling survival and vigor following acorn removal and water stress

Treesearch

E.R. Thorn; W.M. Tzilkowski

1991-01-01

A lack of viable acorns, due to rodent depredation, may be the primary cause of advanced regeneration failure of oak in Pennsylvania. White oak (Quercus alba) acorns germinate immediately upon falling.

Release characteristics of reattached barnacles to non-toxic silicone coatings.

PubMed

Kim, Jongsoo; Nyren-Erickson, Erin; Stafslien, Shane; Daniels, Justin; Bahr, James; Chisholm, Bret J

2008-01-01

Release mechanisms of barnacles (Amphibalanus amphitrite or Balanus amphitrite) reattached to platinum-cured silicone coatings were studied as a function of coating thickness (210-770 microm), elastic modulus (0.08-1.3 MPa), and shear rate (2-22 microm s(-1)). It was found that the shear stress of the reattached, live barnacles necessary to remove from the silicone coatings was controlled by the combined term (E/t)(0.5) of the elastic modulus (E) and thickness (t). As the ratio of the elastic modulus to coating thickness decreased, the barnacles were more readily removed from the silicone coatings, showing a similar release behavior to pseudobarnacles (epoxy glue). The barnacle mean shear stress ranged from 0.017 to 0.055 MPa whereas the pseudobarnacle mean shear stress ranged from 0.022 to 0.095 MPa.

Forecasting long-term acorn production with and without oak decline using forest inventory data

Treesearch

Cathryn H. Greenberg; Chad E. Keyser; Leah C. Rathburn; Anita K. Rose; Todd M. Fearer; Henry W. McNab

2013-01-01

Acorns are important as wildlife food and for oak regeneration, but production is highly variable, posing a challenge to forest managers targeting acorn production levels. Forest managers need tools to predict acorn production capability tailored to individual landscapes and forest management scenarios, adjusting for oak mortality and stand development over time. We...

Acorn Production Prediction Models for Five Common Oak Species of the Eastern United States

Treesearch

Anita K. Rose; Cathryn H. Greenberg; Todd M. Fearer

2011-01-01

Acorn production varies considerably among oak (Quercus) species, individual trees, years, and locations, which directly affects oak regeneration and populations of wildlife species that depend on acorns for food. Hard mast indices provide a relative ranking and basis for comparison of within- and between-year acorn crop size at a broad scale, but do...

Simple tool for planting acorns

Treesearch

William R. Beaufait

1957-01-01

A handy, inexpensive tool for planting acorns has been developed at the Delta Research Center of the Southern Forest Experiment Station and used successfully in experimental plantings. One of its merits is that it ensures a planting hole of eactly the desired depth.

Barnacles - recorders of environmental conditions with unique geochemical signatures

NASA Astrophysics Data System (ADS)

Vinzenz Ullmann, Clemens; Gale, Andy; Korte, Christoph; Frei, Robert; Huggett, Jenny; Wray, Dave

2017-04-01

Barnacles are calcite-forming arthropods that occur in a wide range of habitats in modern times and are found in sedimentary successions reaching back to the Paleozoic. Despite potential use of their mostly low-Mg calcite hard parts for palaeoenvironmental reconstructions, their geochemical composition has been little studied. Here, we present the first comprehensive overview of barnacle geochemistry, with C and O isotope, as well as Mg/Ca, Sr/Ca, Mn/Ca and Fe/Ca data for multiple samples of 42 species covering the orders Sessilia, Scalpelliformes, and Lepadiformes. XRD analyses confirm calcite as the only significant carbonate mineral of the studied barnacle shell material. Apart from one species, median Mg/Ca ratios fall below 50 mmol/mol, the approximate limit for low-Mg-calcite. In the order Sessilia, the scuta and terga are on average enriched in Mg by 36 % over the unmoveable plates. Amongst the calcite-forming marine animals, barnacles have very high Sr/Ca ratios of 2.6 to 5.9 mmol/mol, amongst the highest known for calcite secreting animals. Mn/Ca and Fe/Ca ratios are commonly low and compatible with other modern shell calcite, but can be strongly enriched to > 1 mmol/mol in proximal habitats, particularly close to areas strongly affected by human activity. Carbon and oxygen isotope data indicate formation of the calcite in or near isotopic equilibrium with ambient water conditions. Apart from species showing δ18O values below 0 ‰ V-PDB, a negative correlation of oxygen isotope ratios with Sr/Ca ratios is observed, which may be related to metabolic activity. Compositional patterns in barnacle shell material, particularly high Sr concentrations and Mg distribution in shell plates of the Sessilia, point to a great potential of barnacles for high fidelity reconstruction of past seawater chemistry and environmental conditions complementary to other archives.

Spatial and Temporal Distribution of Weeviled Acorns within a Northern Red oak Seedling Orchard

Treesearch

D.R. Miller; S.E. Scharbaum

2004-01-01

Acorn insects can have a severe impact on mass production and regeneration. Gibson (1972) reported losses of 10 to 100 percent of acorn crops in stands of white oak, whereas Gibson (1982) reported losses of up to 96 percent in stands of northern red oak. Acorn insects can be divided into two groups: primary and secondary insects. The primary insects include the...

Morphometric and molecular identification of individual barnacle cyprids from wild plankton: an approach to detecting fouling and invasive barnacle species.

PubMed

Chen, Hsi-Nien; Høeg, Jens T; Chan, Benny K K

2013-01-01

The present study used DNA barcodes to identify individual cyprids to species. This enables accurate quantification of larvae of potential fouling species in the plankton. In addition, it explains the settlement patterns of barnacles and serves as an early warning system of unwanted immigrant species. Sequences from a total of 540 individual cypris larvae from Taiwanese waters formed 36 monophyletic clades (species) in a phylogenetic tree. Of these clades, 26 were identified to species, but 10 unknown monophyletic clades represented non-native species. Cyprids of the invasive barnacle, Megabalanus cocopoma, were identified. Multivariate analysis of antennular morphometric characters revealed three significant clusters in a nMDS plot, viz. a bell-shaped attachment organ (most species), a shoe-shaped attachment organ (some species), and a spear-shaped attachment organ (coral barnacles only). These differences in attachment organ structure indicate that antennular structures interact directly with the diverse substrata involved in cirripede settlement.

Elemental stoichiometry and compositions of weevil larvae and two acorn hosts under natural phosphorus variation

NASA Astrophysics Data System (ADS)

Ji, Huawei; Du, Baoming; Liu, Chunjiang

2017-04-01

To understand how different trophic organisms in a parasite food chain adapt to the differences in soil nutrient conditions, we investigated stoichiometric variation and homeostasis of multiple elements in two acorn trees, Quercus variabilis and Quercus acutissima, and their parasite weevil larvae (Curculio davidi Fairmaire) at phosphorus (P)-deficient and P-rich sites in subtropical China where P-rich ores are scattered among dominant P-deficient soils. Results showed that elemental stoichiometry and compositions of both acorns and weevil larvae differed significantly between P-deficient and P-rich sites (p < 0.05), with the largest contribution of acorn and weevil larva P in distinguishing the stoichiometric compositions between the two site types. The two acorn species were statistically separated by their acorn elemental stoichiometry and compositions (p < 0.05), but no difference was observed on weevil larvae between the two acorn species. P was one of the few elements that were non strict homeostasis in both acorns and weevil larvae. These findings highlight the importance of both environmental influence in elemental stoichiometry and composition and physiological regulations of nutritional needs in organisms and provide possible stoichiometric responses of both plants and animals to P loading, a worldwide issue from excess release of P into the environment.

Dynamics of acorn production by five species of Southern Appalachian oaks

Treesearch

Cathryn H. Greenberg; Bernard R. Parresol

2002-01-01

The management implications of fluctuations in acorn crop size underscore the need to better understand their patterns, causal factors, and predictability (both within a year and long term). Acorn yield has a demonstrable influence on the population dynamics of many wildlife species, both game (Eiler et al. 1989, Wentworth et al. 1992) and nongame (Hannon et al. 1987,...

Understanding the native Californian diet: Identification of condensed and hydrolyzable tannins in tanoak acorns (Lithocarpus densiflorus).

PubMed

Meyers, Katherine J; Swiecki, Tedmund J; Mitchell, Alyson E

2006-10-04

The tanoak (Lithocarpus densiflorus) acorn was a staple food in the Native American diet and is still used in traditional dishes. Acorns from the genus Quercus have been shown to contain a large range of hydrolyzable tannins. However, neither hydrolyzable nor condensed tannins have been characterized in tanoak acorns. The aim of this study was to identify the full range of hydrolyzable and condensed tannins in extracts of tanoak acorns using liquid chromatography/electrospray ionization-mass spectrometry/mass spectrometry. Condensed tannins were identified as B type oligomers of (epi)-catechin (procyanidins) with a degree of polymerization up to six. Oligomers up to and including tetramers were identified by UV spectra and MS detection whereas pentamers and hexamers were detected only by MS. The total concentration of condensed tannins was 464 mg/100 g acorn pericarp. The concentration of propocyanidin monomers, dimers, trimers, and tetramers in acorn pericarp (mg/100 g acorn pericarp) were 95 +/- 10.9, 148 +/- 35.0, 90 +/- 17.9, and 131 +/- 1.9, respectively. No procyanidins were found in the acorn cotyledon tissue. A total of 22 hydrolyzable tannins were identified in methanolic extracts of acorn cotyledon tissue. Gallic acid derivatives predominated and included galloylated esters of glucose, hexahydrodiphenoyl esters of glucose, and methylated gallates. Galloylated esters of glucose were present as isomers of galloyl glucose, digalloyl glucose, and trigalloyl glucose. Mass spectral fragmentation patterns indicate the presence of one gallic acid-galloyl glucose isomer and two gallic acid-digalloyl-glucose isomers. No isomers of tetragalloyl glucose and pentagalloyl glucose were identified. Ellagic acid and ellagic acid pentoside were also identified.

Acorn Size as a Factor in Early Seedling Growth of Blue Oaks

Treesearch

Jerry Tecklin; Douglas D. McCreary

1991-01-01

Field performance was evaluated for blue oak (Quercus douglasii Hook. & Am.) acorns of different size classes (weights) and from different trees which produced predominantly small, medium, or large acorns. Emergence, height, and survival were monitored for two growing seasons. A parallel evaluation, mainly of root characteristics, was conducted...

The Physiology and Biochemistry of Desiccating White Oak and Cherrybark Oak Acorns

Treesearch

Kristina F. Connor; Sharon Sowa

2004-01-01

The recalcitrant behavior of white oak (Quercus alba L.) and cherrybark oak (Q. pagoda Raf.) acorns was examined in terms of effects of moisture content on seed longevity, viability, and biochemistry. Acorns of both species were fully hydrated and then subjected to drying under ambient conditions of temperature and relative...

Improving Germination of Nuttall Oak Acorns

Treesearch

R. L. Johnson

1967-01-01

Under simulated field conditions the best treatment for germination of acorns of Quercus nuttallii Palmer was a combination of sowing 1 inch below soil surface, under litter, and in partial shade. Supplemental watering was also advantageous. The most important factor was depth of sowing.

The overwintering biology of the acorn weevil, Curculio glandium in southwestern Ontario.

PubMed

Udaka, Hiroko; Sinclair, Brent J

2014-08-01

The acorn weevil, Curculio glandium, is a widespread predator of acorns in eastern North America that overwinters in the soil as a larva. It is possible that low temperatures limit its northern geographic range, so we determined the cold tolerance strategy, seasonal variation in cold tolerance, and explored the physiological plasticity of overwintering larvae. Weevil larvae were collected from acorns of red and bur oak from Pelee Island, southwestern Ontario in fall 2010 and 2011. C. glandium larvae are freeze avoidant and larvae collected from bur oak acorns had lower supercooling points (SCPs: -7.6±0.36°C, LT50: -7.2°C) than those collected from red oak acorns (SCPs: -6.1±0.40°C, LT50: -6.1°C). In the winter of 2010-2011, SCPs and water content decreased, however these changes did not occur in 2011-2012, when winter soil temperatures fluctuated greatly in the absence of the buffering effect of snow. To examine whether larvae utilize cryoprotective dehydration, larvae from red oak acorns were exposed to -5°C in the presence of ice for seven days. These conditions decreased the SCP without affecting water content, suggesting that SCP and water content are not directly coupled. Finally, long-term acclimation at 0°C for six weeks slightly increased cold tolerance but also did not affect water content. Thus, although larval diet affects cold tolerance, there is limited plasticity after other treatments. The soil temperatures we observed were not close to lethal limits, although we speculate that soil temperatures in northerly habitats, or in years of reduced snow cover, has the potential to cause mortality in the field. Copyright © 2014 Elsevier Ltd. All rights reserved.

Darwin's "beloved barnacles": tough lessons in variation.

PubMed

Mannouris, Costas

2011-01-01

In 1846, burdened by insecurity and self-doubt, and having been convinced that he needed to study some group of organisms closely, Darwin embarked on an eight-year odyssey in the protean and perplexing world of barnacles. At the time, he was searching for evidence in support of his theory of evolution by natural selection. In the course of his long study of barnacles, however, he was not just validating his preexisting theoretical system, but was also modifying his views on such fundamental aspects as the universality of individual variation, which is the focus of this paper. According to this notion, the members of any population of living things are expected to exhibit sufficient differences from one another for natural selection to operate. By emphasizing the theoretical value of the barnacle project, my analysis contributes to the historiographic tradition which highlights the significance of the period between the first comprehensive formulation of the theory of evolution by natural selection in 1844 and its urgent publication in the late 1850s. In the course of these years, Darwin's theory was not just accumulating empirical laurels, but was also expected to adapt to a changing conceptual landscape.

Can incubators work in Africa? Acorn Technologies and the entrepreneur-centric model

PubMed Central

2010-01-01

Background Incubators are organizations that support the growth of new and typically technology-based enterprises, by providing business support services that bring together human and financial capital. Although the traditional role of incubators has been for economic development, they may also be a useful policy lever to tackle global health, by fostering the development and delivery of local health innovation. Given its high disease burden, life sciences incubators hold particular potential for Africa. As the most industrially advanced African nation, South Africa serves as a litmus test for identifying effective incubator policies. The case study method was used to illustrate how one such publicly funded incubator founded in 2002, Acorn Technologies, helped to catalyze local health product innovation. Discussion Acorn helped to support twelve biomedical device firms. One of them, Real World Diagnostics, was founded by a trainee from Acorn’s innovative internship program (Hellfire). It developed rapid strip diagnostic tests for locally prevalent diseases including schistosomiasis and HIV, and reported $2 million (USD) in revenue in 2009. Acorn achieved this success by operating as a non-profit virtual incubator with little physical infrastructure. Employing a virtual model in combination with stringent selection criteria of capital efficiency for clients proved to be effective in reducing its own fixed costs. Acorn focused on entrepreneurship training and networking, both critical at an early stage in an environment dominated by multinational biomedical device companies. Acorn and its clients learned that employing a cross-subsidy business model allowed one to generate royalty revenue through imports to subsidize R&D for local diseases. However, funding constraints and government expectations for rapid self-sustainability forced Acorn to merge with its sister biotechnology incubator in 2009. Summary A key to Acorn’s achievements was identifying entrepreneurs

ESR dating pleistocene barnacles from BC and Maine: a new method for tracking sea level change.

PubMed

Blackwell, Bonnie A B; Gong, J J J; Skinner, Anne R; Blais-Stevens, Andrée; Nelson, Robert E; Blickstein, Joel I B

2010-02-01

Barnacles have never been successfully dated by electron spin resonance (ESR). Living mainly in the intertidal zone, barnacles die when sea level changes cause their permanent exposure. Thus, dating the barnacles dates past sea level changes. From this, we can measure apparent sea level changes that occur due to ocean volume changes, crustal isostasy, and tectonics. ESR can date aragonitic mollusc shells ranging in age from 5 ka to at least 500 ka. By modifying the standard ESR method for molluscs to chemically dissolve 20 microm from off the shells, six barnacle samples from Norridgewock, Maine, and Khyex River, British Columbia, were tested for suitability for ESR dating. Due to Mn2+ interference peaks, the four Maine barnacle samples were not datable by ESR. Two barnacles from BC, which lacked Mn2+ interference, yielded a mean ESR age of 15.1 +/- 1.0 ka. These ages agree well with 14C dates on the barnacles themselves and wood in the overlying glaciomarine sediment. Although stability tests to calculate the mean dating signal lifetime and more ESR calibration tests against other barnacles of known age are needed to ensure the method's accuracy, ESR can indeed date Balanus, and thus, sea level changes.

Oak mast production and animal impacts on acorn survival in the central hardwoods

Treesearch

Kenneth F. Kellner; Jeffery K. Riegel; Nathanael I. Lichti; Robert K. Swihart

2013-01-01

As part of the Hardwood Ecosystem Experiment we measured mast production in white (Quercus alba) and black (Q. velutina) oak, and quantified the impacts of seed predators on acorn survival over a 3-year period. Specifically, we measured the proportion of acorns of each species infested with weevils (Curculio spp...

Mammal caching of oak acorns in a red pine and a mixed oak stand

Treesearch

E.R. Thorn; W.M. Tzilkowski

1991-01-01

Small mammal caching of oak (Quercus spp.) acorns in adjacent red pine (Pinus resinosa) and mixed-oak stands was investigated at The Penn State Experimental Forest, Huntingdon Co., Pennsylvania. Gray squirrels (Sciurus carolinensis) and mice (Peromyscus spp.) were the most common acorn-caching...

Effect of acorn size on development of northern red oak 1-0 seedlings

Treesearch

Paul P. Kormanik; Shi-Jean S. Sung; T.L. Kormanik; S.E. Schlarbaum; Stanley J. Zarnoch

1998-01-01

The effect of acorn size on seedling development was determined for 20 northern red oak (Quercus rubra L.) mother tree selections from the USDA Forest Service's Eastern Tennessee Watauga seed orchard. Acorns from each mother tree were visually separated into three size groups, weighed, and sown separately in forest nurseries located in Georgia,...

Recyclable plastics as substrata for settlement and growth of bryozoans Bugula neritina and barnacles Amphibalanus amphitrite.

PubMed

Li, Heng-Xiang; Orihuela, Beatriz; Zhu, Mei; Rittschof, Daniel

2016-11-01

Plastics are common and pervasive anthropogenic debris in marine environments. Floating plastics provide opportunities to alter the abundance, distribution and invasion potential of sessile organisms that colonize them. We selected plastics from seven recycle categories and quantified settlement of (i) bryozoans Bugula neritina (Linnaeus, 1758) in the lab and in the field, and of (ii) barnacles Amphibalanus (= Balanus) amphitrite (Darwin, 1854) in the field. In the laboratory we cultured barnacles on the plastics for 8 weeks and quantified growth, mortality, and breaking strength of the side plates. In the field all recyclable plastics were settlement substrata for bryozoans and barnacles. Settlement depended on the type of plastic. Fewer barnacles settled on plastic surfaces compared to glass. In the lab and in the field, bryozoan settlement was higher on plastics than on glass. In static laboratory rearing, barnacles growing on plastics were initially significantly smaller than on glass. This suggested juvenile barnacles were adversely impacted by materials leaching from the plastics. Barnacle mortality was not significantly different between plastic and glass surfaces, but breaking strength of side plates of barnacles on polyvinyl chloride (PVC) and polycarbonate (PC) were significantly lower than breakage strength on glass. Plastics impact marine ecosystems directly by providing new surfaces for colonization with fouling organisms and by contaminants shown previously to leach out of plastics and impact biological processes. Published by Elsevier Ltd.

Insects that damage northern red oak acorns

Treesearch

Lester P. Gibson

1982-01-01

From 1961 to 1964 and in 1979, the insects found damaging acorns of northern red oak (Quercus rubra L.) in their relative order of abundance were: Curculio proboscideus F., C. sulcatulus (Casey), Melissopus latiferreanus (Wals.), C. nasicus (Say), C. orthorhynchus...

Patterns of tanoak acorn production in Phytophthora ramorum infested and uninfested stands in Big Sur, California, with insights from girdled tanoaks

Treesearch

Leila Hadj-Chikh; Kerri Frangioso; Keyt Fischer; Sarah Bergemann; Ebba Peterson

2006-01-01

Although tanoak (Lithocarpus densiflorus) acorns are a valuable source of food for many species of wildlife few data on tanoak acorn production exist. We conducted studies of acorn production in tanoaks to understand the potential impact of Phytophthora ramorum on acorn availability to wildlife. In 2002 we established 3-ha seed-...

How does prolonged exposure to natural conditions affect acorn moisture and viability?

Treesearch

Kristina Connor; Jillian Donahoo; Gretchen Schafer

2006-01-01

After placing acorns on a lab bench to dry, we saw changes in moisture content, germination, and seed biochemistry in as few as 3 days. As drying progressed, we found that irrevocable damage to membrane lipids and protein secondary structure occurred in just 5 days. However, we did not know if these experiments mimic what happens to acorns in the field. We cleared an...

Does the shelterwood method to regenerate oak forests affect acorn production and predation?

Treesearch

M.I. Bellocq; C. Jones; D.C. Dey; J.J. Turgeon

2005-01-01

The shelterwood system is one of the primary methods currently used to encourage regeneration of oak forests; yet, little is known about its influence on acorn production and predation. We compared acorn production, and predation by insects and mammals in stands of red oak (Quercus rubra L.) that were regenerated by the shelterwood method (50% canopy...

Evaluating desiccation sensitivity of northern red oak acorns using x-ray image analysis

Treesearch

Rosa C. Goodman; Douglass F. Jacobs

2005-01-01

Desiccation of northern red oak (Quercus rubra L.) acorns can have a major influence on seed viability. Recalcitrant behavior of northern red oak acorns was studied to examine the effects of moisture content (MC) on germination and early growth. Because it is rapid and non-destructive, X-ray image analysis was chosen to assess cotyledon damage in...

Viability of litter-stored Quercus falcata Michx. acorns after simulated prescribed winter burns

Treesearch

Michael D. Cain; Michael G. Shelton

1998-01-01

Partially stratified (11 days) southern red oak (Quercus falcata Michx.) acorns were placed at three depths in a reconstructed forest floor and subjected to simulated prescribed winter burns. Within the forest floor, acorns were placed within the L layer, at the upper-F/ lower-F interface, and at the lower-F/mineral-soil interface. Winds for a...

Grafting influences on early acorn production in swamp white oak (Quercus bicolor Wild.)

Treesearch

Mark V. Coggeshall; J.W. Van Sambeek; H.E. Garrett

2008-01-01

Early fruiting of swamp white oak planting stock has been observed. The potential to exploit this trait for wildlife enhancement purposes was evaluated in a grafting study. Scions from both precocious and non-precocious ortets were grafted onto a series of related seedling rootstock sources. Acorn production was recorded through age 4 years. Acorn productivity of the...

A Comparison of Trap Versus Ground Collection of Acorns to Assess Insect Infestation

Treesearch

Roger W. Perry; Alex Mangini

1997-01-01

Oak (Quercus spp.) species are a significant portion of the forest in the Eastern United States. Oaks provide valuable timber products and habitat for many wildlife species. Acorns are essential for oak regeneration and are a major food source for more than 186 species of birds and mammals. Great variation in annual acorn production causes dramatic fluctuations in seed...

Tannin extraction pretreatment and very high gravity fermentation of acorn starch for bioethanol production.

PubMed

Chao, Bin; Liu, Ruiliang; Zhang, Xueling; Zhang, Xu; Tan, Tianwei

2017-10-01

The bioethanol production from a novel non-grain feedstock, acorn starch, was studied in this work. The inhibition of tannin in strain growth was investigated, and the effect of tannin was negligible when the tannin concentration was lower than 1g/L in medium. Therefore, the extraction of tannin was performed using 40% (v/v) ethanol-water solution as the solvent for three times under the conditions of solid/liquid ratio 1:20, 60°C, 3h, by which more than 80% of tannin in acorn was extracted and the content of tannin in acorn decreased from 7.4% (w/w) to 1.5% (w/w). Very high gravity (VHG) fermentation technology was subsequently carried out to achieve a high ethanol concentration at 86.4g/L. A comprehensive process for bioethanol production from acorn starch was designed and a preliminary economic assessment was then performed revealing that this process appeared technically and economically justified. Copyright © 2017 Elsevier Ltd. All rights reserved.

Using X-Ray Image Analysis to Assess the Viability of Northern Red Oak Acorns: Implications for Seed Handlers

Treesearch

Rosa C. Goodman; Douglass F. Jacobs; Robert P. Karrfalt

2006-01-01

This paper discusses the potential to use X-ray image analysis as a rapid and nondestructive test of viability of northern red oak (Quercus rubra L.) acorns and the methodology to do so. Acorns are sensitive to desiccation and lose viability as moisture content (MC) decreases, so we examined X-ray images for cotyledon damage in dried acorns to...

Precisely proportioned: intertidal barnacles alter penis form to suit coastal wave action

PubMed Central

Neufeld, Christopher J; Palmer, A. Richard

2008-01-01

For their size, barnacles possess the longest penis of any animal (up to eight times their body length). However, as one of few sessile animals to copulate, they face a trade-off between reaching more mates and controlling ever-longer penises in turbulent flow. We observed that penises of an intertidal barnacle (Balanus glandula) from wave-exposed shores were shorter than, stouter than, and more than twice as massive for their length as, those from nearby protected bays. In addition, penis shape variation was tightly correlated with maximum velocity of breaking waves, and, on all shores, larger barnacles had disproportionately stouter penises. Finally, field experiments confirmed that most of this variation was due to phenotypic plasticity: barnacles transplanted to a wave-exposed outer coast produced dramatically shorter and wider penises than counterparts moved to a protected harbour. Owing to the probable trade-off between penis length and ability to function in flow, and owing to the ever-changing wave conditions on rocky shores, intertidal barnacles appear to have acquired the capacity to change the size and shape of their penises to suit local hydrodynamic conditions. This dramatic plasticity in genital form is a valuable reminder that factors other than the usual drivers of genital diversification—female choice, sexual conflict and male–male competition—can influence genital form. PMID:18252665

Precisely proportioned: intertidal barnacles alter penis form to suit coastal wave action.

PubMed

Neufeld, Christopher J; Palmer, A Richard

2008-05-07

For their size, barnacles possess the longest penis of any animal (up to eight times their body length). However, as one of few sessile animals to copulate, they face a trade-off between reaching more mates and controlling ever-longer penises in turbulent flow. We observed that penises of an intertidal barnacle (Balanus glandula) from wave-exposed shores were shorter than, stouter than, and more than twice as massive for their length as, those from nearby protected bays. In addition, penis shape variation was tightly correlated with maximum velocity of breaking waves, and, on all shores, larger barnacles had disproportionately stouter penises. Finally, field experiments confirmed that most of this variation was due to phenotypic plasticity: barnacles transplanted to a wave-exposed outer coast produced dramatically shorter and wider penises than counterparts moved to a protected harbour. Owing to the probable trade-off between penis length and ability to function in flow, and owing to the ever-changing wave conditions on rocky shores, intertidal barnacles appear to have acquired the capacity to change the size and shape of their penises to suit local hydrodynamic conditions. This dramatic plasticity in genital form is a valuable reminder that factors other than the usual drivers of genital diversification--female choice, sexual conflict and male-male competition--can influence genital form.

Field Germination of Nuttall Oak Acorns

Treesearch

R. L. Johnson

1970-01-01

In newly cleared plots on Sharkey clay near Stoneville, Mississippi, germination was as high as 79 percent for Nuttall oak (Quercus nuttallii Palmer) acorns sown unstratified in January and 86 percent for those stratified and sown in April. Most seedlings appeared in June and July , when soil temperatures were usually between 80° and 90° F....

Mechanical properties of the cement of the stalked barnacle Dosima fascicularis (Cirripedia, Crustacea)

PubMed Central

Zheden, Vanessa; Klepal, Waltraud; Gorb, Stanislav N.; Kovalev, Alexander

2015-01-01

The stalked barnacle Dosima fascicularis secretes foam-like cement, the amount of which usually exceeds that produced by other barnacles. When Dosima settles on small objects, this adhesive is additionally used as a float which gives buoyancy to the animal. The dual use of the cement by D. fascicularis requires mechanical properties different from those of other barnacle species. In the float, two regions with different morphological structure and mechanical properties can be distinguished. The outer compact zone with small gas-filled bubbles (cells) is harder than the interior one and forms a protective rind presumably against mechanical damage. The inner region with large, gas-filled cells is soft. This study demonstrates that D. fascicularis cement is soft and visco-elastic. We show that the values of the elastic modulus, hardness and tensile stress are considerably lower than in the rigid cement of other barnacles. PMID:25657833

Oceanic barnacles act as foundation species on plastic debris: implications for marine dispersal.

PubMed

Gil, Michael A; Pfaller, Joseph B

2016-01-27

Plastic has emerged as an abundant, stable substratum for oceanic dispersal of organisms via rafting. However, the ecological mechanisms underlying community diversity on plastic debris remain poorly understood. On a cruise from California to Hawai'i, we surveyed plastic debris, some likely originating from the 2011 Tōhoku tsunami, to examine the relationship between rafting community diversity and both habitat area and stalked barnacle (Lepas spp.) abundance. For sessile taxa richness, we observed an interaction in which the positive effect of debris area weakened the negative effect of barnacle cover. In contrast, for mobile taxa richness, including cohabiting species from opposite sides of the Pacific Ocean, barnacle abundance had a positive effect that was strongest at smaller debris sizes. These findings suggest that barnacles, through interactions with habitat area, have trait-dependent effects on other species, serving as both foundation species and competitors, mediating the diversity and dispersal potential of marine organisms on plastic debris.

Oceanic barnacles act as foundation species on plastic debris: implications for marine dispersal

PubMed Central

Gil, Michael A.; Pfaller, Joseph B.

2016-01-01

Plastic has emerged as an abundant, stable substratum for oceanic dispersal of organisms via rafting. However, the ecological mechanisms underlying community diversity on plastic debris remain poorly understood. On a cruise from California to Hawai’i, we surveyed plastic debris, some likely originating from the 2011 Tōhoku tsunami, to examine the relationship between rafting community diversity and both habitat area and stalked barnacle (Lepas spp.) abundance. For sessile taxa richness, we observed an interaction in which the positive effect of debris area weakened the negative effect of barnacle cover. In contrast, for mobile taxa richness, including cohabiting species from opposite sides of the Pacific Ocean, barnacle abundance had a positive effect that was strongest at smaller debris sizes. These findings suggest that barnacles, through interactions with habitat area, have trait-dependent effects on other species, serving as both foundation species and competitors, mediating the diversity and dispersal potential of marine organisms on plastic debris. PMID:26813348

Planting depth effects and water potential effects on oak seedling emergence and acorn germination

Treesearch

Wayne A. Smiles; Jeffrey O. Dawson

1995-01-01

The effects of four planting depths (0, 3, 7, 11 cm) and acorn size on the percentage seedling emergence of red, pin, and black oak were determined. In a complimentary study, the effects of five water potential treatments (0, -.2, -.4, -.6, -1.0 MPa) on the percentage germination of red, pin, and black oak acorns were measured.

Influence of weather on pollination and acorn production in two species of Missouri oaks

Treesearch

Robert A. Cecich

1997-01-01

The process by which oak pistillate flowers become acorns is reasonably understood from an anatomical perspective; however, the way that various factors influence this process is still unclear. This study examined acorn production in a small population of white oak and black oak trees in central Missouri, from 1990 to 1995, in relation to weather variables (maximum and...

Effect of acorn moisture content at sowing on germination and seedling growth of white oak and northern red oak

Treesearch

Shi-Jean Susana Sung; Paul P. Kormanik; Catharine D. Cook; Stanley J. Zarnoch; Taryn L. Kormanik

2006-01-01

White oak (Quercus alba L.) and northern red oak (Q. rubra L.) acorns were collected locally or from seed orchards in October 2002. Mean acorn moisture content (MC) was 48 percent for white oak and 39 percent for northern red oak. These acorns were air dried to different MCs before being sown into nursery beds in early December...

White oak epicotyl emergence and 1-0 seedling growth from surgically altered germinating acorns

Treesearch

Shi-Jean Susana Sung; Paul P. Kormanik; Stanley J. Zarnoch

2010-01-01

Open-pollinated white oak (Quercus alba L.) acorns were collected and stored at 4 °C in November 2004. Three days before sowing in early December, we treated germinating acorns in five ways: no surgery (C); one half of the radical cut off (HR); whole radicle cut off (WR); one cotyledonary petiole severed (OP); and both cotyledonary petioles severed,...

Acorn Production on the Missouri Ozark Forest Ecosystem Project Study Sites: Pre-treatment Data

Treesearch

Larry D. Vangilder

1997-01-01

In the pre-treatment phase of a study to determine if even- and uneven-aged forest management affects the production of acorns on the Missourt Forest Ecosystem Project (MOFEP) study sites, acorn production was measured on the nine study sites by randomly placing from 2 to 6 plots in each of four ecological land type (ELT) groupings (N=130 plots). A split-plot...

Effect of acorn meal-water combinations on technological properties and fine structure of gluten-free bread.

PubMed

Skendi, Adriana; Mouselemidou, Panagiota; Papageorgiou, Maria; Papastergiadis, Efthimios

2018-07-01

Gluten-free breads were developed from rice flour and corn starch at a constant ratio 1:1 with acorn meal addition (5, 15, 25%), at three levels of water (65, 70, 75%). Acorn supplemented gluten free breads better met sensory preference than rice breads in terms of colour (brown hue was enhanced) and were also nutritionally improved in terms of total phenolics. The specific volume of breads significantly decreased with increasing acorn addition while crumb hardness was also increased. SEM images confirmed that the decrease in the ΔH values at low water level (65%) was due to less swelling of starch as observed from large starch granule remnants present after baking. XRD measurements revealed coexistence of "B" and "V" type starch structures. Increasing of acorn concentration enhanced the intensity of FTIR bands at 994, 1016 and 1077 cm -1 . Copyright © 2018 Elsevier Ltd. All rights reserved.

Acorn Production Characteristics of Southern Appalachian Oaks: A Simple Method to Predict Within-Year Crop Size

Treesearch

Cathryn H. Greenberg; Bernard R. Parresol

2000-01-01

We examined acorn production from 1993-97 by black oak (Quercus velutina Lam.), northern red oak (Q. rubra L.), scarlet oak (Q. coccinea Muenchh.), chestnut oak (Q. prinus L.), and white oak (Q. alba L.) in the Southern Appalichians to determine how frequency of acorn...

Case Study: New York ACORN. Strong Neighborhoods, Strong Schools. The Indicators Project on Education Organizing.

ERIC Educational Resources Information Center

Simon, Elaine; Pickron-Davis, Marcine; Brown, Chris

This report describes New York City's ACORN (Association of Community Organizations for Reform Now), which has a 20-year history of organizing in the City and emphasizes public education issues. ACORN works at both the neighborhood and policy level. It is one of five case studies in the Indicators Project on Education Organizing, which identified…

The effect of storage temperature and duration on northern red oak acorn viability and vigour

Treesearch

Thomas L. Noland; Andree E. Morneault; Daniel C. Dey; Dave Deugo

2013-01-01

Three separate collections of Ontario sources of northern red oak (Quercus rubra L.) acorns were made to determine the effects of long-term cold storage at +2°C, -1°C, and -2°C on their viability and vigour. We measured acorn moisture content, percent germination during storage, speed of germination and total germination...

Preventing Growth Of Barnacles On Propellers

NASA Technical Reports Server (NTRS)

Parrish, Kemp L.

1993-01-01

Possible to prevent barnacles and other marine life from obtaining firm bonds on propellers and other metal parts by coating parts with NEDOX (or equivalent) cavitation-resistant material. Available in several forms; one that works best is mold-release coating. Also provides improved surface hardness, protection against electrolysis, better resistance to abrasion, and less friction between propellers and water.

ACORN's Accelerated Income Redistribution Project: A Program Evaluation

ERIC Educational Resources Information Center

Brooks, Fred; Russell, Daniel; Fisher, Robert

2006-01-01

Objective: This study evaluated the Association of Community Organizations for Reform Now's (ACORN) efforts to increase the uptake of families claiming the earned income tax credit through door-to-door canvassing and managing free tax preparation clinics in three pilot cities. Method: The mixed-method program evaluation included administrative…

Gypsy moth impacts on oak acorn production

Treesearch

Kurt W. Gottschalk

1991-01-01

Gypsy moth outbreaks can have drastic effects on many f a s t resources and uses. Because gypsy moth prefers oak foliage, oak stands are the most susceptible to defoliation and resultant damage. The value of oak mast for many wildlife species is high. The high carbohydrate content of acorns provides the energy necessary for winter survival. Loss of mast crops due to...

Users guide to ACORn: a comprehensive Ozark regeneration simulator.

Treesearch

Daniel C. Dey; Michael Ter-Mikaelian; Paul S. Johnson; Stephen R. Shifley

1996-01-01

Describes how to use the ACORn computer program for predicting number of trees per acre and stocking percent by species and diameter classes 21 years after complete overstory removal of oak stands in the Ozark Highlands of Missouri and adjacent States.

New Techniques for High-Contrast Imaging with ADI: The ACORNS-ADI SEEDS Data Reduction Pipeline

NASA Technical Reports Server (NTRS)

Brandt, Timothy D.; McElwain, Michael W.; Turner, Edwin L.; Abe, L.; Brandner, W.; Carson, J.; Egner, S.; Feldt, M.; Golota, T.; Grady, C. A.;

The fluid dynamics of Balanus glandula barnacles: Adaptations to sheltered and exposed habitats.

PubMed

Vo, Maureen; Mehrabian, Sasan; Villalpando, Fernando; Etienne, Stephane; Pelletier, Dominique; Cameron, Christopher B

2018-04-11

Suspension feeders use a wide range of appendages to capture particles from the surrounding fluid. Their functioning, either as a paddle or a sieve, depends on the leakiness, or amount of fluid that passes through the gaps between the appendages. Balanus glandula is the most common species of barnacle distributed along the Pacific coast of North America. It shows a strong phenotypic response to water flow velocity. Individuals from exposed, high flow sites have short and robust cirral filters, whereas those from sheltered, low velocity sites have long, spindly appendages. Computational fluid dynamics (CFD) simulations of these two ecophenotypes were done using a finite volume method. Leakiness was determined by simulating flow velocity fields at increasing Reynolds numbers, results that have been unattainable at higher velocities by observation. CFD also allowed us to characterize flow in hard to see regions of the feeding legs (rami). Laser-illumination experiments were performed at low to medium flow velocities in a flume tank and corroborated results from CFD. Barnacle filters from a sheltered site become completely leaky at Re=2.24(0.16m/s), well above the maximum habitat velocity, suggesting that this ecophenotype is not mechanically optimized for feeding. Barnacles from exposed environments become fully leaky within the range of habitat velocities Re=3.50(0.18m/s). Our CFD results revealed that the drag force on exposed barnacles feeding appendages are the same as the sheltered barnacles feeding appendages despite their shape difference and spacing ratio. Copyright © 2018 Elsevier Ltd. All rights reserved.

Multiple origins and incursions of the Atlantic barnacle Chthamalus proteus in the Pacific.

PubMed

Zardus, John D; Hadfield, Michael G

2005-10-01

Chthamalus proteus, a barnacle native to the Caribbean and western Atlantic, was introduced to the Pacific within the last few decades. Using direct sequencing of mitochondrial DNA (COI), we characterized genetic variation in native and introduced populations and searched for genetic matches between regions to determine if there were multiple geographical sources and introduction points for this barnacle. In the native range, we found great genetic differences among populations (max. F(ST) = 0.613) encompassing four lineages: one endemic to Panama, one endemic to Brazil, and two occurring Caribbean-wide. All four lineages were represented in the Pacific, but not equally; the Brazilian lineage was most prevalent and the Panamanian least common. Twenty-one individuals spread among nearly every island from where the barnacle is known in the Pacific, exactly matched six haplotypes scattered among Curaçao, the Netherlands Antilles; St John, US Virgin Islands; Puerto Rico; and Brazil, confirming a multigeographical origin for the Pacific populations. Significant genetic differences were also found in introduced populations from the Hawaiian Islands (F(CT) = 0.043, P < 0.001), indicating introduction events have occurred at more than one locality. However, the sequence, timing and number of arrival events remains unknown. Possible reasons for limited transport of this barnacle through the Panama Canal are discussed. This and a preponderance of Brazilian-type individuals in the Pacific suggest an unexpected route of entry from around Cape Horn, South America. Unification in the Pacific of historically divergent lineages of this barnacle raises the possibility for selection of 'hybrids' with novel ecological adaptations in its new environment.

"Barnacle Bill" and Surrounding from Super-Pan

NASA Image and Video Library

1997-10-14

This is an image from the super-pan sequence. Of importance are some of the features around the rock nicknamed Barnacle Bill in the left foreground. The rock shows a "streamlined tail" composed of particles deposited by wind on the leeward (downwind) side of the rock. Also seen is a "moat" around the opposite (windward) side of the rock where either erosion (or non-deposition) of fine sediment has occurred. Mars Pathfinder scientist believe that the wind blowing over and around rocks like Barnacle Bill creates an airflow pattern wherein a buffer zone is formed immediately upwind of the rock and airflow patterns keep sediment from being deposited directly upwind of Barnacle Bill. On the downwind side, however, the airflow is complex and a small wake and tapered "dead air zone" form. Sediment can be deposited within this region, the shape of the formed deposit corresponds to the airflow patterns that exist behind the rock. Similar features have been observed at the Viking landing sites, and are thought to form under high wind conditions during the autumn and winter seasons in the northern hemisphere. This image mosaic was processed by the U.S. Geological Survey in support of the NASA/JPL Mars Pathfinder Mars Mission. Sojourner spent 83 days of a planned seven-day mission exploring the Martian terrain, acquiring images, and taking chemical, atmospheric and other measurements. The final data transmission received from Pathfinder was at 10:23 UTC on September 27, 1997. Although mission managers tried to restore full communications during the following five months, the successful mission was terminated on March 10, 1998. http://photojournal.jpl.nasa.gov/catalog/PIA00982

Oaks, Acorns, Climate and Squirrels, An Environmental Investigation.

ERIC Educational Resources Information Center

National Wildlife Federation, Washington, DC.

This environmental unit is one of a series designed for integration within an existing curriculum. The unit is self-contained and requires minimal teacher preparation. The philosophy of the units is based on an experience-oriented process that encourages self-paced independent student work. In this particular unit, oaks and acorns are the vehicle…

Gooseneck barnacles (Lepas spp.) ingest microplastic debris in the North Pacific Subtropical Gyre.

PubMed

Goldstein, Miriam C; Goodwin, Deborah S

2013-01-01

Substantial quantities of small plastic particles, termed "microplastic," have been found in many areas of the world ocean, and have accumulated in particularly high densities on the surface of the subtropical gyres. While plastic debris has been documented on the surface of the North Pacific Subtropical Gyre (NPSG) since the early 1970s, the ecological implications remain poorly understood. Organisms associated with floating objects, termed the "rafting assemblage," are an important component of the NPSG ecosystem. These objects are often dominated by abundant and fast-growing gooseneck barnacles (Lepas spp.), which predate on plankton and larval fishes at the sea surface. To assess the potential effects of microplastic on the rafting community, we examined the gastrointestinal tracts of 385 barnacles collected from the NPSG for evidence of plastic ingestion. We found that 33.5% of the barnacles had plastic particles present in their gastrointestinal tract, ranging from one plastic particle to a maximum of 30 particles. Particle ingestion was positively correlated to capitulum length, and no blockage of the stomach or intestines was observed. The majority of ingested plastic was polyethylene, with polypropylene and polystyrene also present. Our results suggest that barnacle ingestion of microplastic is relatively common, with unknown trophic impacts on the rafting community and the NPSG ecosystem.

Effects of flood duration and season on germination of black, cherrybark, northern red, and water oak acorns

Treesearch

Yanfei Guo; Michael G. Shelton; Brian R. Lockhart

1998-01-01

Effects of flood duration (0, 10, 20, and 30 days) and season (winter and spring) on acorn germination were tested for two upland oaks [black and northern red oak (Quercus velutina Lam. and Q. rubra L.)] and two bottomland oaks [cherrybark and water oak (Q. pagoda Raf. and Q. nigra L.)]. Acorns...

Memristive Model of the Barnacle Giant Muscle Fibers

NASA Astrophysics Data System (ADS)

Sah, Maheshwar Pd.; Kim, Hyongsuk; Eroglu, Abdullah; Chua, Leon

The generation of action potentials (oscillations) in biological systems is a complex, yet poorly understood nonlinear dynamical phenomenon involving ions. This paper reveals that the time-varying calcium ion and the time-varying potassium ion, which are essential for generating action potentials in Barnacle giant muscle fibers are in fact generic memristors in the perspective of electrical circuit theory. We will show that these two ions exhibit all the fingerprints of memristors from the equations of the Morris-Lecar model of the Barnacle giant muscle fibers. This paper also gives a textbook reference to understand the difference between memristor and nonlinear resistor via analysis of the potassium ion-channel memristor and calcium ion-channel nonlinear resistor. We will also present a comprehensive in-depth analysis of the generation of action potentials (oscillations) in memristive Morris-Lecar model using small-signal circuit model and the Hopf bifurcation theorem.

New Techniques for High-contrast Imaging with ADI: The ACORNS-ADI SEEDS Data Reduction Pipeline

NASA Astrophysics Data System (ADS)

Brandt, Timothy D.; McElwain, Michael W.; Turner, Edwin L.; Abe, L.; Brandner, W.; Carson, J.; Egner, S.; Feldt, M.; Golota, T.; Goto, M.; Grady, C. A.; Guyon, O.; Hashimoto, J.; Hayano, Y.; Hayashi, M.; Hayashi, S.; Henning, T.; Hodapp, K. W.; Ishii, M.; Iye, M.; Janson, M.; Kandori, R.; Knapp, G. R.; Kudo, T.; Kusakabe, N.; Kuzuhara, M.; Kwon, J.; Matsuo, T.; Miyama, S.; Morino, J.-I.; Moro-Martín, A.; Nishimura, T.; Pyo, T.-S.; Serabyn, E.; Suto, H.; Suzuki, R.; Takami, M.; Takato, N.; Terada, H.; Thalmann, C.; Tomono, D.; Watanabe, M.; Wisniewski, J. P.; Yamada, T.; Takami, H.; Usuda, T.; Tamura, M.

2013-02-01

We describe Algorithms for Calibration, Optimized Registration, and Nulling the Star in Angular Differential Imaging (ACORNS-ADI), a new, parallelized software package to reduce high-contrast imaging data, and its application to data from the SEEDS survey. We implement several new algorithms, including a method to register saturated images, a trimmed mean for combining an image sequence that reduces noise by up to ~20%, and a robust and computationally fast method to compute the sensitivity of a high-contrast observation everywhere on the field of view without introducing artificial sources. We also include a description of image processing steps to remove electronic artifacts specific to Hawaii2-RG detectors like the one used for SEEDS, and a detailed analysis of the Locally Optimized Combination of Images (LOCI) algorithm commonly used to reduce high-contrast imaging data. ACORNS-ADI is written in python. It is efficient and open-source, and includes several optional features which may improve performance on data from other instruments. ACORNS-ADI requires minimal modification to reduce data from instruments other than HiCIAO. It is freely available for download at www.github.com/t-brandt/acorns-adi under a Berkeley Software Distribution (BSD) license. Based on data collected at Subaru Telescope, which is operated by the National Astronomical Observatory of Japan.

How to Manage Oak Forests for Acorn Production

Treesearch

Paul Johnson

1994-01-01

Oak forests are life support systems for the many animals that live in them. Acorns, a staple product of oaks forests, are eaten by many species of birds and mammals including deer, bear, squirrels, mice, rabbits, foxes, raccoons, grackles, turkey, grouse, quail, blue jays, woodpeckers, and waterfowl. The population and health of wildlife often rise and fall with the...

Cool barnacles: Do common biogenic structures enhance or retard rates of deterioration of intertidal rocks and concrete?

PubMed

Coombes, Martin A; Viles, Heather A; Naylor, Larissa A; La Marca, Emanuela Claudia

2017-02-15

Sedentary and mobile organisms grow profusely on hard substrates within the coastal zone and contribute to the deterioration of coastal engineering structures and the geomorphic evolution of rocky shores by both enhancing and retarding weathering and erosion. There is a lack of quantitative evidence for the direction and magnitude of these effects. This study assesses the influence of globally-abundant intertidal organisms, barnacles, by measuring the response of limestone, granite and marine-grade concrete colonised with varying percentage covers of Chthamalus spp. under simulated, temperate intertidal conditions. Temperature regimes at 5 and 10mm below the surface of each material demonstrated a consistent and statistically significant negative relationship between barnacle abundance and indicators of thermal breakdown. With a 95% cover of barnacles, subsurface peak temperatures were reduced by 1.59°C for limestone, 5.54°C for concrete and 5.97°C for granite in comparison to no barnacle cover. The amplitudes of short-term (15-30min) thermal fluctuations conducive to breakdown via 'fatigue' effects were also buffered by 0.70°C in limestone, 1.50°C in concrete and 1.63°C in granite. Furthermore, concentrations of potentially damaging salt ions were consistently lower under barnacles in limestone and concrete. These results indicate that barnacles do not enhance, but likely reduce rates of mechanical breakdown on rock and concrete by buffering near-surface thermal cycling and reducing salt ion ingress. In these ways, we highlight the potential role of barnacles as agents of bioprotection. These findings support growing international efforts to enhance the ecological value of hard coastal structures by facilitating their colonisation (where appropriate) through design interventions. Copyright © 2016 Elsevier B.V. All rights reserved.

The Temporal and Spatial Distribution of Filbert Weevil Infested Acorns in an Oak Woodland in Marin County, California

Treesearch

Vernard R. Lewis

1991-01-01

Two-hundred shoots contained within randomly selected locations from each of thirty-six coast live oak, Quercus agrifolia, trees were sampled to determine the abundance and spatial distribution of acorns infested by the filbert weevil, Curculio occidentis in northern California during 1989. The seasonal abundance of infested acorns...

Adaptive evolution of sexual systems in pedunculate barnacles

PubMed Central

Yusa, Yoichi; Yoshikawa, Mai; Kitaura, Jun; Kawane, Masako; Ozaki, Yuki; Yamato, Shigeyuki; Høeg, Jens T.

2012-01-01

How and why diverse sexual systems evolve are fascinating evolutionary questions, but few empirical studies have dealt with these questions in animals. Pedunculate (gooseneck) barnacles show such diversity, including simultaneous hermaphroditism, coexistence of dwarf males and hermaphrodites (androdioecy), and coexistence of dwarf males and females (dioecy). Here, we report the first phylogenetically controlled test of the hypothesis that the ultimate cause of the diverse sexual systems and presence of dwarf males in this group is limited mating opportunities for non-dwarf individuals, owing to mating in small groups. Within the pedunculate barnacle phylogeny, dwarf males and females have evolved repeatedly. Females are more likely to evolve in androdioecious than hermaphroditic populations, suggesting that evolution of dwarf males has preceded that of females in pedunculates. Both dwarf males and females are associated with a higher proportion of solitary individuals in the population, corroborating the hypothesis that limited mating opportunities have favoured evolution of these diverse sexual systems, which have puzzled biologists since Darwin. PMID:21881138

The Geographic Distribution of a Tropical Montane Bird Is Limited by a Tree: Acorn Woodpeckers (Melanerpes formicivorus) and Colombian Oaks (Quercus humboldtii) in the Northern Andes

PubMed Central

2015-01-01

Species distributions are limited by a complex array of abiotic and biotic factors. In general, abiotic (climatic) factors are thought to explain species’ broad geographic distributions, while biotic factors regulate species’ abundance patterns at local scales. We used species distribution models to test the hypothesis that a biotic interaction with a tree, the Colombian oak (Quercus humboldtii), limits the broad-scale distribution of the Acorn Woodpecker (Melanerpes formicivorus) in the Northern Andes of South America. North American populations of Acorn Woodpeckers consume acorns from Quercus oaks and are limited by the presence of Quercus oaks. However, Acorn Woodpeckers in the Northern Andes seldom consume Colombian oak acorns (though may regularly drink sap from oak trees) and have been observed at sites without Colombian oaks, the sole species of Quercus found in South America. We found that climate-only models overpredicted Acorn Woodpecker distribution, suggesting that suitable abiotic conditions (e.g. in northern Ecuador) exist beyond the woodpecker’s southern range margin. In contrast, models that incorporate Colombian oak presence outperformed climate-only models and more accurately predicted the location of the Acorn Woodpecker’s southern range margin in southern Colombia. These findings support the hypothesis that a biotic interaction with Colombian oaks sets Acorn Woodpecker’s broad-scale geographic limit in South America, probably because Acorn Woodpeckers rely on Colombian oaks as a food resource (possibly for the oak’s sap rather than for acorns). Although empirical examples of particular plants limiting tropical birds’ distributions are scarce, we predict that similar biotic interactions may play an important role in structuring the geographic distributions of many species of tropical montane birds with specialized foraging behavior. PMID:26083262

Gooseneck barnacles (Lepas spp.) ingest microplastic debris in the North Pacific Subtropical Gyre

PubMed Central

Goodwin, Deborah S.

2013-01-01

Substantial quantities of small plastic particles, termed “microplastic,” have been found in many areas of the world ocean, and have accumulated in particularly high densities on the surface of the subtropical gyres. While plastic debris has been documented on the surface of the North Pacific Subtropical Gyre (NPSG) since the early 1970s, the ecological implications remain poorly understood. Organisms associated with floating objects, termed the “rafting assemblage,” are an important component of the NPSG ecosystem. These objects are often dominated by abundant and fast-growing gooseneck barnacles (Lepas spp.), which predate on plankton and larval fishes at the sea surface. To assess the potential effects of microplastic on the rafting community, we examined the gastrointestinal tracts of 385 barnacles collected from the NPSG for evidence of plastic ingestion. We found that 33.5% of the barnacles had plastic particles present in their gastrointestinal tract, ranging from one plastic particle to a maximum of 30 particles. Particle ingestion was positively correlated to capitulum length, and no blockage of the stomach or intestines was observed. The majority of ingested plastic was polyethylene, with polypropylene and polystyrene also present. Our results suggest that barnacle ingestion of microplastic is relatively common, with unknown trophic impacts on the rafting community and the NPSG ecosystem. PMID:24167779

Metamorphosis in the Cirripede Crustacean Balanus amphitrite

PubMed Central

Maruzzo, Diego; Aldred, Nick; Clare, Anthony S.; Høeg, Jens T.

2012-01-01

Stalked and acorn barnacles (Cirripedia Thoracica) have a complex life cycle that includes a free-swimming nauplius larva, a cypris larva and a permanently attached sessile juvenile and adult barnacle. The barnacle cyprid is among the most highly specialized of marine invertebrate larvae and its settlement biology has been intensively studied. By contrast, surprisingly few papers have dealt with the critical series of metamorphic events from cementation of the cyprid to the substratum until the appearance of a suspension feeding juvenile. This metamorphosis is both ontogenetically complex and critical to the survival of the barnacle. Here we use video microscopy to present a timeline and description of morphological events from settled cyprid to juvenile barnacle in the model species Balanus amphitrite, representing an important step towards both a broader understanding of the settlement ecology of this species and a platform for studying the factors that control its metamorphosis. Metamorphosis in B. amphitrite involves a complex sequence of events: cementation, epidermis separation from the cypris cuticle, degeneration of cypris musculature, rotation of the thorax inside the mantle cavity, building of the juvenile musculature, contraction of antennular muscles, raising of the body, shedding of the cypris cuticle, shell plate and basis formation and, possibly, a further moult to become a suspension feeding barnacle. We compare these events with developmental information from other barnacle species and discuss them in the framework of barnacle settlement ecology. PMID:22666355

Predicting free-space occupancy on novel artificial structures by an invasive intertidal barnacle using a removal experiment.

PubMed

Bracewell, Sally A; Robinson, Leonie A; Firth, Louise B; Knights, Antony M

2013-01-01

Artificial structures can create novel habitat in the marine environment that has been associated with the spread of invasive species. They are often located in areas of high disturbance and can vary significantly in the area of free space provided for settlement of marine organisms. Whilst correlation between the amount of free space available and recruitment success has been shown in populations of several marine benthic organisms, there has been relatively little focus on invasive species, a group with the potential to reproduce in vast numbers and colonise habitats rapidly. Invasion success following different scales of disturbance was examined in the invasive acorn barnacle, Austrominiusmodestus, on a unique art installation located in Liverpool Bay. Population growth and recruitment success were examined by comparing recruitment rates within disturbance clearings of 4 different sizes and by contrasting population development with early recruitment rates over a 10 week period. Disturbed areas were rapidly recolonised and monocultures of A. modestus formed within 6 weeks. The size of patch created during disturbance had no effect on the rate of recruitment, while a linear relationship between recruit density and patch size was observed. Density-dependent processes mediated initial high recruitment resulting in population stability after 8-10 weeks, but densities continued to greatly exceed those reported in natural habitats. Given that artificial structures are likely to continue to proliferate in light of climate change projections, free-space is likely to become more available more frequently in the future supporting the expansion of fast-colonising species.

Migrations of California gray whales tracked by oxygen-18 variations in their epizoic barnacles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Killingley, J.S.

1980-02-15

Barnacles attached to the California gray whale have oxygen isotope compositions that serve as a record of changing ocean temperatures as the whale migrates between arctic and subtropical waters. The isotopic values for the barnacles can be used to track whale migrations and to reconstruct the recent movements of beached whales. The method may be useful for tracing the movements of other animals, living or fossil, and for reconstructing the voyages of ancient ships.

Transcriptomic Analysis of Neuropeptides and Peptide Hormones in the Barnacle Balanus amphitrite: Evidence of Roles in Larval Settlement

PubMed Central

Yan, Xing-Cheng; Chen, Zhang-Fan; Sun, Jin; Matsumura, Kiyotaka; Wu, Rudolf S. S.; Qian, Pei-Yuan

2012-01-01

The barnacle Balanus amphitrite is a globally distributed marine crustacean and has been used as a model species for intertidal ecology and biofouling studies. Its life cycle consists of seven planktonic larval stages followed by a sessile juvenile/adult stage. The transitional processes between larval stages and juveniles are crucial for barnacle development and recruitment. Although some studies have been conducted on the neuroanatomy and neuroactive substances of the barnacle, a comprehensive understanding of neuropeptides and peptide hormones remains lacking. To better characterize barnacle neuropeptidome and its potential roles in larval settlement, an in silico identification of putative transcripts encoding neuropeptides/peptide hormones was performed, based on transcriptome of the barnacle B. amphitrite that has been recently sequenced. Potential cleavage sites andstructure of mature peptides were predicted through homology search of known arthropod peptides. In total, 16 neuropeptide families/subfamilies were predicted from the barnacle transcriptome, and 14 of them were confirmed as genuine neuropeptides by Rapid Amplification of cDNA Ends. Analysis of peptide precursor structures and mature sequences showed that some neuropeptides of B. amphitrite are novel isoforms and shared similar characteristics with their homologs from insects. The expression profiling of predicted neuropeptide genes revealed that pigment dispersing hormone, SIFamide, calcitonin, and B-type allatostatin had the highest expression level in cypris stage, while tachykinin-related peptide was down regulated in both cyprids and juveniles. Furthermore, an inhibitor of proprotein convertase related to peptide maturation effectively delayed larval metamorphosis. Combination of real-time PCR results and bioassay indicated that certain neuropeptides may play an important role in cypris settlement. Overall, new insight into neuropeptides/peptide hormones characterized in this study shall

Effect of drying temperatures on starch-related functional and thermal properties of acorn flours.

PubMed

Correia, P R; Beirão-da-Costa, M L

2011-03-01

The application of starchy flours from different origins in food systems depends greatly on information about the chemical and functional properties of such food materials. Acorns are important forestry resources in the central and southern regions of Portugal. To preserve these fruits and to optimize their use, techniques like drying are needed. The effects of different drying temperatures on starch-related functional properties of acorn flours obtained from dried fruits of Quercus rotundifolia (QR) and Quercus suber (QS) were evaluated. Flours were characterized for amylose and resistant starch (RS) contents, swelling ability, and gelatinization properties. Drying temperature mainly affected amylose content and viscoamylographic properties. Amylograms of flours from fruits dried at 60 °C displayed higher consistency (2102 B.U. and 1560 B.U., respectively, for QR and QS). The transition temperatures and enthalpy were less affected by drying temperature, suggesting few modifications in starch structure during drying. QR flours presented different functional properties to those obtained from QS acorn flours. The effect of drying temperatures were more evident in QR.

Darwin and barnacles.

PubMed

Deutsch, Jean

2010-02-01

In this essay, I discuss the origin of Charles Darwin's interest in cirripedes (barnacles). Indeed, he worked intensively on cirripedes during the years in which he was developing the theory that eventually led to the publication of The Origin of Species. In the light of our present knowledge, I present Darwin's achievements in the morphology, systematics and biology of these small marine invertebrates, and also his mistakes. I suggest that the word that sheds the most light here is homology, and that his mistakes were due to following Richard Owen's method of determining homologies by reference to an ideal archetype. I discuss the ways in which his studies on cirripedes influenced the writing of The Origin. 2009 Académie des sciences. Published by Elsevier SAS. All rights reserved.

Impact of acorn moisture content at sowing on germination and seedling growth of white oak and northern red oak

Treesearch

Shi-Jean Susana Sung; Paul P. Kormanik; Taryn L. Kormanik; Stanley J. Zarnoch

2005-01-01

Acorn quality is an integral part of artificial oak regeneration. Progeny from individual mother trees of similar geographic areas frequently exhibited a wide range of germination percentage. The purpose of our study was to evaluate the impact of acorn moisture content (MC) at sowing on germination and subsequent seedling growth.

The Insect Guild of White Oak Acorns: Its Effect on Mast Quality in the Ozark and Ouachita National Forests

Treesearch

Alex C. Mangini; Roger W. Perry

2004-01-01

Abstract - Hardwood regeneration, especially of oaks, is an essential component of ecosystem management in the Ouachita and Ozark Mountains of Arkansas. In addition, oak mast is an important wildlife food. Several species of insects inhabit and consume acorns. Data on the insect guild inhabiting white oak (Quercus alba L.) acorns...

Maturation of Acorns of Cherrybark, Water, and Willow Oaks

Treesearch

F. T. Bonner

1974-01-01

Acorns of cherrybark, water, and willow oaks grew slowly but steadily in July and August and reached maximum size in September, when fats and carbohydrates, the major storage foods, accumulated rapidly. At physiological maturity in late October or early November, crude fat levels were 15 to 20 percent of seed dry weight and carbohydrates totaled 25 percent.

Memorandum for the Heads of Executive Departments and Agencies Acorn Memorandum

EPA Pesticide Factsheets

Memo to inform you that on March 10, 2010, the United States District Court for the Eastern District of New York issued the attached opinion, declaratory judgment, and permanent injunction in Association of Community Organizations for Reform Now (ACORN).

Predation on transmission stages reduces parasitism: sea anemones consume transmission stages of a barnacle parasite.

PubMed

Fong, Caitlin R; Kuris, Armand M

2017-06-01

While parasites serve as prey, it is unclear how the spatial distribution of parasite predators provides transmission control and influences patterns of parasitism. Because many of its organisms are sessile, the rocky intertidal zone is a valuable but little used system to understand spatial patterns of parasitism and elucidate the underlying mechanisms driving these patterns. Sea anemones and barnacles are important space competitors in the rocky intertidal zone along the Pacific coast of North America. Anemones are voracious, indiscriminate predators; thus, they may intercept infectious stages of parasites before they reach a host. We investigate whether a sea anemone protects an associated barnacle from parasitism by Hemioniscus balani, an isopod parasitic castrator. At Coal Oil Point, Santa Barbara, California USA, 29% of barnacles were within 1 cm from an anemone at the surveyed tidal height. Barnacles associated with anemones had reduced parasite prevalence and higher reproductive productivity than those remote from sea anemones. In the laboratory, anemones readily consumed the transmission stage of the parasite. Hence, anemone consumption of parasite transmission stages may provide a mechanism by which community context regulates parasite prevalence at a local scale. Our results suggest predation may be an important process providing parasite transmission control.

Acorn Yield During 1988 and 1989 on California's Central Coast

Treesearch

Sergio L. Garcia; Wayne A. Jensen; William H. Weitkamp; William D. Tietje

1991-01-01

In 1988, a study was began to evaluate acorn yield of valley oak (Quercus lobata), coast live oak (Q. agrifolia), and blue oak (Q. douglasii) in three of California's central coast counties: Santa Barbara, San Luis Obispo, and San Benito. The purpose of the study was to examine the degree and variability of...

Insect-oak interactions with coast live oak (Quercus agrifolia) and Engelmann oak (Q. engelmannii) at the acorn and seedling stage

Treesearch

Connell E. Dunning; Timothy D. Paine; Richard A. Redak

2002-01-01

We determined the impact of insects on both acorns and seedlings of coast live oak (Quercus agrifolia Nee) and Engelmann oak (Quercus engelmannii E. Greene). Our goals were to (1) identify insects feeding on acorns and levels of insect damage, and (2) measure performance and preference of a generalist leaf-feeding insect herbivore...

Reasoning about Natural Selection: Diagnosing Contextual Competency Using the ACORNS Instrument

ERIC Educational Resources Information Center

Nehm, Ross H.; Beggrow, Elizabeth P.; Opfer, John E.; Ha, Minsu

2012-01-01

Studies of students' thinking about natural selection have revealed that the scenarios in which students reason evoke different types, magnitudes, and arrangements of knowledge elements and misconceptions. Diagnostic tests are needed that probe students' thinking across a representative array of evolutionary contexts. The ACORNS is a diagnostic…

Living with marginal coral communities: Diversity and host-specificity in coral-associated barnacles in the northern coral distribution limit of the East China Sea.

PubMed

Chan, Benny K K; Xu, Guang; Kim, Hyun Kyong; Park, Jin-Ho; Kim, Won

2018-01-01

Corals and their associated fauna are extremely diverse in tropical waters and form major reefs. In the high-latitude temperate zone, corals living near their distribution limit are considered marginal communities because they are particularly extremely sensitive to environmental and climatic changes. In this study, we examined the diversity and host usage of coral-associated barnacles on Jeju Island, Korea, the northern coral distribution limit in the East China Sea. In this study, only three coral-associated barnacles-from two genera in two subfamilies-were collected. The Pyrgomatinid barnacles Cantellius arcuatus and Cantellius cf. euspinulosum were found only on the corals Montipora millepora and Alveopora japonica, respectively. The Megatrematinid barnacle Pyrgomina oulastreae, relatively a generalist, was found on Psammocora spp. (both profundacella and albopicta) and Oulastrea crispata corals. The host usage of these three barnacles does not overlap. DNA barcode sequences of the C. arcuatus specimens collected in the present study matched those collected in Kochi in Japan, Taiwan, Malaysia and Papua New Guinea, suggesting that this species has a wide geographical distribution. C. arcuatus covers a wider host range in Taiwan waters, inhabiting Montipora spp. and Porites spp., which suggests that the host specificity of coral-associated barnacles varies with host availability. C. cf. euspinulosum probably has a very narrow distribution and host usage. The sequences of C. cf. euspinulosum on Jeju Island do not match those of any known sequences of Cantellius barnacles in the Indo-Pacific region. P. oulastreae probably prefers cold water because it has been reported in temperate regions. Coral-associated barnacles in marginal communities have considerably lower diversity than their subtropical and tropical counterparts. When host availability is limited, marginal coral-associated barnacles exhibit higher host specificity than those in subtropical and tropical

The effect of acorn insects on the establishment and vigor of northern red oak seedlings in north-central West Virginia

Treesearch

Linda S. Gribko

1995-01-01

During a 2-year investigation into the effect of small mammals on northern red oak (Quercus rubra) acorn survival and germination, widespread germination failure and lack of seedling vigor was apparent in control quadrats on one of two watersheds under study. Insects were present in and on the failed acorns but it was unknown whether they were...

A “Shallow Phylogeny” of Shallow Barnacles (Chthamalus)

PubMed Central

Wares, John P.; Pankey, M. Sabrina; Pitombo, Fabio; Daglio, Liza Gómez; Achituv, Yair

2009-01-01

Background We present a multi-locus phylogenetic analysis of the shallow water (high intertidal) barnacle genus Chthamalus, focusing on member species in the western hemisphere. Understanding the phylogeny of this group improves interpretation of classical ecological work on competition, distributional changes associated with climate change, and the morphological evolution of complex cirripede phenotypes. Methodology and Findings We use traditional and Bayesian phylogenetic and ‘deep coalescent’ approaches to identify a phylogeny that supports the monophyly of the mostly American ‘fissus group’ of Chthamalus, but that also supports a need for taxonomic revision of Chthamalus and Microeuraphia. Two deep phylogeographic breaks were also found within the range of two tropical American taxa (C. angustitergum and C. southwardorum) as well. Conclusions Our data, which include two novel gene regions for phylogenetic analysis of cirripedes, suggest that much more evaluation of the morphological evolutionary history and taxonomy of Chthamalid barnacles is necessary. These data and associated analyses also indicate that the radiation of species in the late Pliocene and Pleistocene was very rapid, and may provide new insights toward speciation via transient allopatry or ecological barriers. PMID:19440543

Climate, Deer, Rodents, and Acorns as Determinants of Variation in Lyme-Disease Risk

PubMed Central

Canham, Charles D; Oggenfuss, Kelly; Winchcombe, Raymond J; Keesing, Felicia

2006-01-01

Risk of human exposure to vector-borne zoonotic pathogens is a function of the abundance and infection prevalence of vectors. We assessed the determinants of Lyme-disease risk (density and Borrelia burgdorferi-infection prevalence of nymphal Ixodes scapularis ticks) over 13 y on several field plots within eastern deciduous forests in the epicenter of US Lyme disease (Dutchess County, New York). We used a model comparison approach to simultaneously test the importance of ambient growing-season temperature, precipitation, two indices of deer (Odocoileus virginianus) abundance, and densities of white-footed mice (Peromyscus leucopus), eastern chipmunks (Tamias striatus), and acorns ( Quercus spp.), in both simple and multiple regression models, in predicting entomological risk. Indices of deer abundance had no predictive power, and precipitation in the current year and temperature in the prior year had only weak effects on entomological risk. The strongest predictors of a current year's risk were the prior year's abundance of mice and chipmunks and abundance of acorns 2 y previously. In no case did inclusion of deer or climate variables improve the predictive power of models based on rodents, acorns, or both. We conclude that interannual variation in entomological risk of exposure to Lyme disease is correlated positively with prior abundance of key hosts for the immature stages of the tick vector and with critical food resources for those hosts. PMID:16669698

Compounds from silicones alter enzyme activity in curing barnacle glue and model enzymes.

PubMed

Rittschof, Daniel; Orihuela, Beatriz; Harder, Tilmann; Stafslien, Shane; Chisholm, Bret; Dickinson, Gary H

2011-02-17

Attachment strength of fouling organisms on silicone coatings is low. We hypothesized that low attachment strength on silicones is, in part, due to the interaction of surface available components with natural glues. Components could alter curing of glues through bulk changes or specifically through altered enzyme activity. GC-MS analysis of silicone coatings showed surface-available siloxanes when the coatings were gently rubbed with a cotton swab for 15 seconds or given a 30 second rinse with methanol. Mixtures of compounds were found on 2 commercial and 8 model silicone coatings. The hypothesis that silicone components alter glue curing enzymes was tested with curing barnacle glue and with commercial enzymes. In our model, barnacle glue curing involves trypsin-like serine protease(s), which activate enzymes and structural proteins, and a transglutaminase which cross-links glue proteins. Transglutaminase activity was significantly altered upon exposure of curing glue from individual barnacles to silicone eluates. Activity of purified trypsin and, to a greater extent, transglutaminase was significantly altered by relevant concentrations of silicone polymer constituents. Surface-associated silicone compounds can disrupt glue curing and alter enzyme properties. Altered curing of natural glues has potential in fouling management.

Barnacle Bill in Super Resolution from Insurance Panorama

NASA Technical Reports Server (NTRS)

1998-01-01

Barnacle Bill is a small rock immediately west-northwest of the Mars Pathfinder lander and was the first rock visited by the Sojourner Rover's alpha proton X-ray spectrometer (APXS) instrument. This image shows super resolution techniques applied to the first APXS target rock, which was never imaged with the rover's forward cameras. Super resolution was applied to help to address questions about the texture of this rock and what it might tell us about its mode of origin.

This view of Barnacle Bill was produced by combining the 'Insurance Pan' frames taken while the IMP camera was still in its stowed position on sol2. The composite color frames that make up this anaglyph were produced for both the right and left eye of the IMP. The right eye composite consists of 5 frames, taken with different color filters, the left eye consists of only 1 frame. The resultant image from each eye was enlarged by 500% and then co-added using Adobe Photoshop to produce, in effect, a super-resolution panchromatic frame that is sharper than an individual frame would be. These panchromatic frames were then colorized with the red, green, and blue filtered images from the same sequence. The color balance was adjusted to approximate the true color of Mars.

The anaglyph view was produced by combining the left with the right eye color composite frames by assigning the left eye composite view to the red color plane and the right eye composite view to the green and blue color planes (cyan), to produce a stereo anaglyph mosaic. This mosaic can be viewed in 3-D on your computer monitor or in color print form by wearing red-blue 3-D glasses.

Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. Barnacle Bill is a small rock immediately west-northwest of the Mars Pathfinder lander and was the first rock visited by the Sojourner Rover's alpha proton X-ray spectrometer (APXS) instrument.

Application of Vegetation Indices to Estimate Acorn Production at Iberian Peninsula

NASA Astrophysics Data System (ADS)

Escribano, Juan A.; Díaz-Ambrona, Carlos G. H.; Recuero, Laura; Huesca, Margarita; Cicuendez, Victor; Palacios, Alicia; Tarquis, Ana M.

2014-05-01

The Iberian pig valued natural resources of the pasture when fattened in mountain. The variability of acorn production is not contained in any line of Spanish agricultural insurance. However, the production of arable pasture is covered by line insurance number 133 for loss of pasture compensation. This scenario is only contemplated for breeding cows and brave bulls, sheep, goats and horses, although pigs are not included. This insurance is established by monitoring ten-day composites Normalized Difference Vegetation Index (NDVI) measured by satellite over treeless pastures, using MODIS TERRA satellite. The aim of this work is to check if we can use a satellite vegetation index to estimate the production of acorns. In order to do so, two Spanish grassland locations have been analyzed: regions of Olivenza (Jerez-Oliva) and Merida (Badajoz). The acorns production was evaluated through 2002-2005 gauging conducted by the Grupo Habitat de la Orden (Badajoz). Medium resolution (500x500 m2) MODIS images were used during the same time period to estimate the ten-day composites NDVI at these locations. Finally, meteorological data was obtained from SIAR and MAGRAMA network stations, calculating the ten-day averaged temperature and ten day accumulated precipitation. Considering two accumulated factors, NDVI and temperature, three phenological stages were well defined being the second one which pointed differences among campaigns. Then, accumulated precipitation versus accumulated NDVI was plot for this second phenological stage obtaining maximum differences at 300 mm of cumulative rainfall. Analyzing acorn production with accumulated NDVI in that moment a production function was obtained with a correlation coefficient of 0.71. These results will be discussed in detail. References J.A. Escribano, C.G.H. Diaz-Ambrona, L. Recuero, M. Huesca, V. Cicuendez, A. Palacios-Orueta y A.M. Tarquis. Aplicacion de Indices de Vegetacion para evaluar la falta de produccion de pastos y

Acorn Caching in Tree Squirrels: Teaching Hypothesis Testing in the Park

ERIC Educational Resources Information Center

McEuen, Amy B.; Steele, Michael A.

2012-01-01

We developed an exercise for a university-level ecology class that teaches hypothesis testing by examining acorn preferences and caching behavior of tree squirrels (Sciurus spp.). This exercise is easily modified to teach concepts of behavioral ecology for earlier grades, particularly high school, and provides students with a theoretical basis for…

Genetic and Morphological Differentiation of the Indo-West Pacific Intertidal Barnacle Chthamalus malayensis

PubMed Central

Tsang, Ling Ming; Wu, Tsz Huen; Shih, Hsi-Te; Williams, Gray A.; Chu, Ka Hou; Chan, Benny K.K.

2012-01-01

Chthamalus malayensis is a common intertidal acorn barnacle widely distributed in the Indo-West Pacific. Analysis of sequences of mitochondrial cytochrome c oxidase subunit I reveals four genetically differentiated clades with almost allopatric distribution in this region. The four clades exhibit morphological differences in arthropodal characters, including the number of conical spines and number of setules of the basal guard setae on the cirri. These characters are, however, highly variable within each clade; such that the absolute range of the number of conical spines and setules overlaps between clades, and therefore, these are not diagnostic characters for taxonomic identification. The geographic distribution of the four clades displays a strong relationship between surface temperatures of the sea and ocean-current realms. The Indo-Malay (IM) clade is widespread in the tropical, equatorial region, including the Indian Ocean, Malay Peninsula, and North Borneo. The South China (SC) and Taiwan (TW) clades are found in tropical to subtropical regions, with the former distributed along the coasts of southern China, Vietnam, Thailand, and the western Philippines under the influence of the South China Warm Current. The TW clade is endemic to Taiwan, while the Christmas Island (CI) clade is confined to CI. There was weak or no population subdivision observed within these clades, suggesting high gene flow within the range of the clades. The clades demonstrate clear signatures of recent demographic expansion that predated the Last Glacial Maximum (LGM), but they have maintained a relatively stable effective population in the past 100,000 years. The persistence of intertidal fauna through the LGM may, therefore, be a common biogeographic pattern. The lack of genetic subdivision in the IM clade across the Indian and Pacific Oceans may be attributed to recent expansion of ranges and the fact that a mutation-drift equilibrium has not been reached, or the relaxed habitat

Adhesive barnacle peptides exhibit a steric-driven design rule to enhance adhesion between asymmetric surfaces.

PubMed

Raman, Sangeetha; Malms, Lukas; Utzig, Thomas; Shrestha, Buddha Ratna; Stock, Philipp; Krishnan, Shankar; Valtiner, Markus

2017-04-01

Barnacles exhibit superior underwater adhesion simply through sequencing of the 21 proteinogenic amino acids, without post processing or using special amino acids. Here, we measure and discuss the molecular interaction of two distinct and recurring short peptide sequences (Bp1 and Bp2) inspired from the surface binding 19kDa protein from the barnacle attachment interface. Using self-assembled monolayer (SAMs) of known physical and chemical properties on molecularly smooth gold substrates in 5mM NaCl at pH 7.3, (1) the adsorption mechanisms of the barnacle inspired peptides are explored using quartz crystal microbalance, and (2) adhesion mediating properties are measured using the surface force apparatus. The hydrophobic Bp1 peptide with a cysteine residue adsorbs irreversibly onto Au surfaces due to thiol bond formation, while on hydrophobic CH 3 SAM surface, the interactions are hydrophobic in nature. Interestingly, Bp2 that contains both hydrophobic and protonated amine units exhibits asymmetric bridging with an exceptionally high adhesion energy up to 100mJ/m 2 between mica and both gold and CH 3 SAM. Surprisingly on hydrophilic surfaces such as COOH- or OH-SAMs both peptides fail to show any interactions, implying the necessity of surface charge to promote bridging. Our results provide insights into the molecular aspects of manipulating and utilizing barnacle-mediated peptides to promote or inhibit underwater adhesion. Copyright © 2016 Elsevier B.V. All rights reserved.

Indirect effects of tending ants on holm oak volatiles and acorn quality

PubMed Central

Llusia, Joan; Peñuelas, Josep

2011-01-01

The indirect effect of ants on plants through their mutualism with honeydew-producing insects has been extensively investigated. Honeydew-producing insects that are tended by ants impose a cost on plant fitness and health by reducing seed production and/or plant growth. This cost is associated with sap intake and virus transmissions but may be overcompesated by tending ants if they deter or prey on hebivorous insects. The balance between cost and benefits depends on the tending ant species. In this study we report other indirect effects on plants of the mutualism between aphids and ants. We have found that two Lasius ant species, one native and the other invasive, may change the composition of volatile organic compounds (VOCs) of the holm oak (Quercus ilex) blend when they tend the aphid Lachnus roboris. The aphid regulation of its feeding and honeydew production according to the ant demands was proposed as a plausible mechanism that triggers changes in VOCs. Additionally, we now report here that aphid feeding, which is located most of the time on acorns cap or petiole, significantly increased the relative content of linolenic acid in acorns from holm oak colonized by the invasive ant. This acid is involved in the response of plants to insect herbivory as a precursor or jasmonic acid. No effect was found on acorn production, germination or seedlings quality. These results suggest that tending-ants may trigger the physiological response of holm oaks involved in plant resistance toward aphid herbivory and this response is ant species-dependent. PMID:21494087

Antioxidant Extracts from Acorns (Quercus ilex L.) Effectively Protect Ready-to-Eat (RTE) Chicken Patties Irrespective of Packaging Atmosphere.

PubMed

Ferreira, Valquíria C S; Morcuende, David; Hérnandez-López, Silvia H; Madruga, Marta S; Silva, Fábio A P; Estévez, Mario

2017-03-01

This study evaluated the impact of a phenolic-rich acorn extract (200 ppm gallic acid equivalents) and the concentration of oxygen in the packaging system (low-oxygen modified atmosphere; 5% vs. normal-oxygen; 21%) on lipid and protein oxidation and consumers acceptance of the ready-to-eat chicken patties. Samples were subjected to cooking (electric oven, 170 °C/16 min), cold storage (14 d at 4 °C), and reheating (microwave, 600 mW/1 min). Samples treated with acorn extract kept thiobarbituric acid-reactive substances numbers and lipid-derived volatiles at basal levels throughout the whole processing irrespective of the oxygen concentration in the packaging atmosphere. Consistently, treated patties had lower protein carbonyls than control ones. The acorn extract also controlled color and texture deterioration during chilled storage and reheating and improved the color and odor acceptance of the products. Formulating with acorn extract is a feasible strategy to inhibit the oxidation-driven changes and preserve the quality of reheated samples as if there were freshly cooked. Compared to the effect of the antioxidant extract, the concentration of oxygen in the packaging system was negligible in terms of quality preservation. © 2017 Institute of Food Technologists®.

Harvest locations of goose barnacles can be successfully discriminated using trace elemental signatures

PubMed Central

Albuquerque, Rui; Queiroga, Henrique; Swearer, Stephen E.; Calado, Ricardo; Leandro, Sérgio M.

2016-01-01

European Union regulations state that consumers must be rightfully informed about the provenance of fishery products to prevent fraudulent practices. However, mislabeling of the geographical origin is a common practice. It is therefore paramount to develop forensic methods that allow all players involved in the supply chain to accurately trace the origin of seafood. In this study, trace elemental signatures (TES) of the goose barnacle Pollicipes pollicipes, collected from ten sites along the Portuguese coast, were employed to discriminate individual’s origin. Barium (Ba), boron (B), cadmium (Cd), chromium (Cr), lithium (Li), magnesium (Mg), manganese (Mn), phosphorous (P), lead (Pb), strontium (Sr) and zinc (Zn) - were quantified using Inductively Coupled Plasma−Mass Spectrometry (ICP-MS). Significant differences were recorded among locations for all elements. A regularized discriminant analysis (RDA) revealed that 83% of all individuals were correctly assigned. This study shows TES can be a reliable tool to confirm the geographic origin of goose barnacles at fine spatial resolution. Although additional studies are required to ascertain the reliability of TES on cooked specimens and the temporal stability of the signature, the approach holds great promise for the management of goose barnacles fisheries, enforcement of conservation policies and assurance in accurate labeling. PMID:27292413

Harvest locations of goose barnacles can be successfully discriminated using trace elemental signatures

NASA Astrophysics Data System (ADS)

Albuquerque, Rui; Queiroga, Henrique; Swearer, Stephen E.; Calado, Ricardo; Leandro, Sérgio M.

2016-06-01

European Union regulations state that consumers must be rightfully informed about the provenance of fishery products to prevent fraudulent practices. However, mislabeling of the geographical origin is a common practice. It is therefore paramount to develop forensic methods that allow all players involved in the supply chain to accurately trace the origin of seafood. In this study, trace elemental signatures (TES) of the goose barnacle Pollicipes pollicipes, collected from ten sites along the Portuguese coast, were employed to discriminate individual’s origin. Barium (Ba), boron (B), cadmium (Cd), chromium (Cr), lithium (Li), magnesium (Mg), manganese (Mn), phosphorous (P), lead (Pb), strontium (Sr) and zinc (Zn) - were quantified using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). Significant differences were recorded among locations for all elements. A regularized discriminant analysis (RDA) revealed that 83% of all individuals were correctly assigned. This study shows TES can be a reliable tool to confirm the geographic origin of goose barnacles at fine spatial resolution. Although additional studies are required to ascertain the reliability of TES on cooked specimens and the temporal stability of the signature, the approach holds great promise for the management of goose barnacles fisheries, enforcement of conservation policies and assurance in accurate labeling.

Compounds from Silicones Alter Enzyme Activity in Curing Barnacle Glue and Model Enzymes

PubMed Central

Rittschof, Daniel; Orihuela, Beatriz; Harder, Tilmann; Stafslien, Shane; Chisholm, Bret; Dickinson, Gary H.

2011-01-01

Background Attachment strength of fouling organisms on silicone coatings is low. We hypothesized that low attachment strength on silicones is, in part, due to the interaction of surface available components with natural glues. Components could alter curing of glues through bulk changes or specifically through altered enzyme activity. Methodology/Principal Findings GC-MS analysis of silicone coatings showed surface-available siloxanes when the coatings were gently rubbed with a cotton swab for 15 seconds or given a 30 second rinse with methanol. Mixtures of compounds were found on 2 commercial and 8 model silicone coatings. The hypothesis that silicone components alter glue curing enzymes was tested with curing barnacle glue and with commercial enzymes. In our model, barnacle glue curing involves trypsin-like serine protease(s), which activate enzymes and structural proteins, and a transglutaminase which cross-links glue proteins. Transglutaminase activity was significantly altered upon exposure of curing glue from individual barnacles to silicone eluates. Activity of purified trypsin and, to a greater extent, transglutaminase was significantly altered by relevant concentrations of silicone polymer constituents. Conclusions/Significance Surface-associated silicone compounds can disrupt glue curing and alter enzyme properties. Altered curing of natural glues has potential in fouling management. PMID:21379573

The effect of boldness on decision-making in barnacle geese is group-size-dependent.

PubMed

Kurvers, Ralf H J M; Adamczyk, Vena M A P; van Wieren, Sipke E; Prins, Herbert H T

2011-07-07

In group-living species, decisions made by individuals may result in collective behaviours. A central question in understanding collective behaviours is how individual variation in phenotype affects collective behaviours. However, how the personality of individuals affects collective decisions in groups remains poorly understood. Here, we investigated the role of boldness on the decision-making process in different-sized groups of barnacle geese. Naive barnacle geese, differing in boldness score, were introduced in a labyrinth in groups with either one or three informed demonstrators. The demonstrators possessed information about the route through the labyrinth. In pairs, the probability of choosing a route prior to the informed demonstrator increased with increasing boldness score: bolder individuals decided more often for themselves where to go compared with shyer individuals, whereas shyer individuals waited more often for the demonstrators to decide and followed this information. In groups of four individuals, however, there was no effect of boldness on decision-making, suggesting that individual differences were less important with increasing group size. Our experimental results show that personality is important in collective decisions in pairs of barnacle geese, and suggest that bolder individuals have a greater influence over the outcome of decisions in groups.

Establishing the ACORN National Practitioner Database: Strategies to Recruit Practitioners to a National Practice-Based Research Network.

PubMed

Adams, Jon; Steel, Amie; Moore, Craig; Amorin-Woods, Lyndon; Sibbritt, David

2016-10-01

The purpose of this paper is to report on the recruitment and promotion strategies employed by the Australian Chiropractic Research Network (ACORN) project aimed at helping recruit a substantial national sample of participants and to describe the features of our practice-based research network (PBRN) design that may provide key insights to others looking to establish a similar network or draw on the ACORN project to conduct sub-studies. The ACORN project followed a multifaceted recruitment and promotion strategy drawing on distinct branding, a practitioner-focused promotion campaign, and a strategically designed questionnaire and distribution/recruitment approach to attract sufficient participation from the ranks of registered chiropractors across Australia. From the 4684 chiropractors registered at the time of recruitment, the project achieved a database response rate of 36% (n = 1680), resulting in a large, nationally representative sample across age, gender, and location. This sample constitutes the largest proportional coverage of participants from any voluntary national PBRN across any single health care profession. It does appear that a number of key promotional and recruitment features of the ACORN project may have helped establish the high response rate for the PBRN, which constitutes an important sustainable resource for future national and international efforts to grow the chiropractic evidence base and research capacity. Further rigorous enquiry is needed to help evaluate the direct contribution of specific promotional and recruitment strategies in attaining high response rates from practitioner populations who may be invited to participate in future PBRNs. Copyright © 2016. Published by Elsevier Inc.

Nest-site selection in the acorn woodpecker

USGS Publications Warehouse

Hooge, P.N.; Stanback, M.T.; Koenig, Walter D.

1999-01-01

Acorn Woodpeckers (Melanerpes formicivorus) at Hastings Reservation in central California prefer to nest in dead limbs in large, dead valley oaks (Quercus lobata) and California sycamores (Platanus racemosa) that are also frequently used as acorn storage trees. Based on 232 nest cavities used over an 18-year period, we tested whether preferred or modal nest-site characters were associated with increased reproductive success (the "nest-site quality" hypothesis). We also examined whether more successful nests were likely to experience more favorable microclimatic conditions or to be less accessible to terrestrial predators. We found only equivocal support for the nest-site quality hypothesis: only 1 of 5 preferred characters and 2 of 10 characters exhibiting a clear modality were correlated with higher reproductive success. All three characteristics of nests known or likely to be associated with a more favorable microclimate, and two of five characteristics likely to render nests less accessible to predators, were correlated with higher reproductive success. These results suggest that nest cavities in this population are built in part to take advantage of favorable microclimatic conditions and, to a lesser extent, to reduce access to predators. However, despite benefits of particular nest characteristics, birds frequently nested in apparently suboptimal cavities. We also found a significant relationship between mean group size and the history of occupancy of particular territories and the probability of nest cavities being built in microclimatically favorable live limbs, suggesting that larger groups residing on more stable territories were better able to construct nests with optimal characteristics. This indicates that there may be demographic, as well as ecological, constraints on nest-site selection in this primary cavity nester.

How do coral barnacles start their life in their hosts?

PubMed

Liu, Jennie Chien Wen; Høeg, Jens Thorvald; Chan, Benny K K

2016-06-01

Coral-associated invertebrates are the most significant contributors to the diversity of reef ecosystems, but no studies have examined how larvae manage to settle and grow in their coral hosts. Video recordings were used to document this process in the coral barnacle Darwiniella angularis associated with the coral Cyphastrea chalcidicum Settlement and metamorphosis in feeding juveniles lasted 8-11 days and comprised six phases. The settling cyprid starts by poking its antennules into the tissue of the prospective host (I: probing stage). The coral releases digestive filaments for defence, but tolerating such attack the cyprid penetrates further (II: battling stage). Ecdysis is completed 2 days after settlement (III: carapace detachment). The barnacle becomes embedded deep in the coral tissue while completing metamorphosis between 4 and 6 days (IV: embedding stage), but reappears as a feeding juvenile 8-11 days after settlement (V: emerging stage; VI: feeding stage). Cyprids preferably settle in areas between the coral polyps, where they have a much higher survival rate than on the polyp surfaces. © 2016 The Author(s).

Stable isotopes in barnacles as a tool to understand green sea turtle (Chelonia mydas) regional movement patterns

NASA Astrophysics Data System (ADS)

Detjen, M.; Sterling, E.; Gómez, A.

2015-12-01

Sea turtles are migratory animals that travel long distances between their feeding and breeding grounds. Traditional methods for researching sea turtle migratory behavior have important disadvantages, and the development of alternatives would enhance our ability to monitor and manage these globally endangered species. Here we report on the isotope signatures in green sea-turtle (Chelonia mydas) barnacles (Platylepas sp.) and discuss their potential relevance as tools with which to study green sea turtle migration and habitat use patterns. We analyzed oxygen (δ18O) and carbon (δ13C) isotope ratios in barnacle calcite layers from specimens collected from green turtles captured at the Palmyra Atoll National Wildlife Refuge (PANWR) in the central Pacific. Carbon isotopes were not informative in this study. However, the oxygen isotope results suggest likely regional movement patterns when mapped onto a predictive oxygen isotope map of the Pacific. Barnacle proxies could therefore complement other methods in understanding regional movement patterns, informing more effective conservation policy that takes into account connectivity between populations.

Stable isotopes in barnacles as a tool to understand green sea turtle (Chelonia mydas) regional movement patterns

NASA Astrophysics Data System (ADS)

Detjen, M.; Sterling, E.; Gómez, A.

2015-03-01

Sea turtles are migratory animals that travel long distances between their feeding and breeding grounds. Traditional methods for researching sea turtle migratory behavior have important disadvantages, and the development of alternatives would enhance our ability to monitor and manage these globally endangered species. Here we report on the isotope signatures in green sea turtle (Chelonia mydas) barnacles (Platylepas sp.) and discuss their potential relevance as tools with which to study green sea turtle migration and habitat use patterns. We analyzed oxygen (δ18O) and carbon (δ13C) isotope ratios in barnacle calcite layers from specimens collected from green turtles captured at the Palmyra Atoll National Wildlife Refuge (PANWR) in the Central Pacific. Carbon isotopes were not informative in this study. However, the oxygen isotope results suggest likely regional movement patterns when mapped onto a predictive oxygen isotope map of the Pacific. Barnacle proxies could therefore complement other methods in understanding regional movement patterns, informing more effective conservation policy that takes into account connectivity between populations.

The effect of boldness on decision-making in barnacle geese is group-size-dependent

PubMed Central

Kurvers, Ralf H. J. M.; Adamczyk, Vena M. A. P.; van Wieren, Sipke E.; Prins, Herbert H. T.

2011-01-01

In group-living species, decisions made by individuals may result in collective behaviours. A central question in understanding collective behaviours is how individual variation in phenotype affects collective behaviours. However, how the personality of individuals affects collective decisions in groups remains poorly understood. Here, we investigated the role of boldness on the decision-making process in different-sized groups of barnacle geese. Naive barnacle geese, differing in boldness score, were introduced in a labyrinth in groups with either one or three informed demonstrators. The demonstrators possessed information about the route through the labyrinth. In pairs, the probability of choosing a route prior to the informed demonstrator increased with increasing boldness score: bolder individuals decided more often for themselves where to go compared with shyer individuals, whereas shyer individuals waited more often for the demonstrators to decide and followed this information. In groups of four individuals, however, there was no effect of boldness on decision-making, suggesting that individual differences were less important with increasing group size. Our experimental results show that personality is important in collective decisions in pairs of barnacle geese, and suggest that bolder individuals have a greater influence over the outcome of decisions in groups. PMID:21123271

The aCORN backscatter-suppressed beta spectrometer

DOE PAGES

Hassan, M. T.; Bateman, F.; Collett, B.; ...

2017-06-16

Backscatter of electrons from a beta detector, with incomplete energy deposition, can lead to undesirable effects in many types of experiments. We present and discuss the design and operation of a backscatter-suppressed beta spectrometer that was developed as part of a program to measure the electron–antineutrino correlation coefficient in neutron beta decay (aCORN). An array of backscatter veto detectors surrounds a plastic scintillator beta energy detector. The spectrometer contains an axial magnetic field gradient, so electrons are efficiently admitted but have a low probability for escaping back through the entrance after backscattering. Lastly, the design, construction, calibration, and performance ofmore » the spectrometer are discussed.« less

Toxicological impact of methanolic extract of the leaves and acorns of the cork oak on Culiseta annulata, S in Algeria

NASA Astrophysics Data System (ADS)

Amel, Aouati

2018-05-01

The methanolic extract of leaves and acorns of cork oak tree was tested against 4th instar larvae of the mosquito Culiseta annulata Schrank, 1776. The obtained results indicated a sensitivity of Culiseta annulata larvae for the plant species aroused. This sensitivity is even higher when exposure of the larvae to insecticides is extended in time. Generates the greatest mortality rate 83% for 1g /l after 72 h of exposure against 39% for 1g /l after 24 h exposure for the extract of leaves and acorns of cork oak. For LC50 values, leaves and acorns of cork oak acted at low concentrations with an LC50of 439mg /l after 72 h of exposure. thus, these findings can help in the development of alternatives to the chemical hazardous insecticide to the environment like the use of plants that are generally available and not toxic to the fauna and flora.

Attraction of acorn-infesting Cydia latiferreana (lepidoptera:tortricidae) to pheromone-baited traps

Treesearch

J.W. Peacock; S.L. Wright; J.R. Galford

1988-01-01

Males of acorn-infesting Cydia latiferreana are attracted to an equilibrium mixture of the four isomers of 8, I10-dodecadien-1-ol acetate, the virgin female-produced pheromone. Trap height relative to the height of trees in which traps are placed seems to be a significant factor influencing moth catches at attractant-baited traps. In an oak woodlot...

Effects of desiccation on the physiology and biochemistry of Quercus alba acorns

Treesearch

Kristina F. Connor; Sharon Sowa

2003-01-01

Seeds that lose viability when dried to a water content of less than 12% are said to be recalcitrant. We subjected acorns of Quercus alba L., a species with recalcitrant seeds, to desiccation to determine the effects of drying on lipids, proteins and carbohydrates of the embryonic axis and cotyledon tissues. Samples of fresh seed and seed dried for...

Connectivity modeling and graph theory analysis predict recolonization in transient populations

NASA Astrophysics Data System (ADS)

Rognstad, Rhiannon L.; Wethey, David S.; Oliver, Hilde; Hilbish, Thomas J.

2018-07-01

Population connectivity plays a major role in the ecology and evolution of marine organisms. In these systems, connectivity of many species occurs primarily during a larval stage, when larvae are frequently too small and numerous to track directly. To indirectly estimate larval dispersal, ocean circulation models have emerged as a popular technique. Here we use regional ocean circulation models to estimate dispersal of the intertidal barnacle Semibalanus balanoides at its local distribution limit in Southwest England. We incorporate historical and recent repatriation events to provide support for our modeled dispersal estimates, which predict a recolonization rate similar to that observed in two recolonization events. Using graph theory techniques to describe the dispersal landscape, we identify likely physical barriers to dispersal in the region. Our results demonstrate the use of recolonization data to support dispersal models and how these models can be used to describe population connectivity.

Ecology and Evolution of Phenotypic Plasticity in the Penis and Cirri of Barnacles.

PubMed

Hoch, J Matthew; Schneck, Daniel T; Neufeld, Christopher J

2016-10-01

Most barnacles are sessile, simultaneous hermaphrodites that reproduce by copulation. This is achieved through the extension of a muscular penis, famous for being the proportionally largest in the animal kingdom. The penis is a long cylindrical or conical organ, composed of a series of folded rings, allowing it to stretch to great lengths. The penises are covered with chemosensory setae allowing them to seek out receptive neighbors. For many species, the condition of the penis changes seasonally. In the most extreme circumstances, it degenerates and is shed during the first post-mating molt and is re-grown for the next mating season. Barnacle penises have been shown to exhibit phenotypic plasticity in response to many different challenges. When exposed to heavy waves, diameter is increased by thickening both the cuticle and muscles. When mates are far, length increases by adding ringed annulations. Experiments have shown that these plastic traits are modular, capable of changing independently from each other and that they improve mating ability. Alternate strategies to increase reproductive ability by barnacles include the production of dwarf and complemental males, sperm casting and sperm leakage, and aerial copulation. All of these mating strategies may have important implications for the study of reproductive biology, life history, and sex allocation theory. © The Author 2016. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

Determinants of Acorn Productivity Among Five Species of Oaks in Central Coastal California

Treesearch

Walter D. Koenig; William J. Carmen; Mark T. Stanback; Mumme Ronald L.

1991-01-01

We measured acorn production of five species of oaks (genus Quercus) over a ten year period (1980-1989) at Hastings Reservation in Monterey County, California. Crop production was highly variable and generally asynchronous between species. Variance in crop size decreased directly with increasing species diversity across sub-areas within the study...

New alien barnacles in the Azores and some remarks on the invasive potential of Balanidae

NASA Astrophysics Data System (ADS)

Torres, Paulo; Costa, Ana Cristina; Dionísio, Maria Ana

2012-12-01

Global homogenization of biota is underway through worldwide introduction and establishment of non-indigenous (exotic) species. Organisms fouling ship hulls are continually in transit and can affect communities through biodiversity loss and serious damage to economy and public health. In the Azores, for the first time, underwater alien species prospection was conducted in marinas and recreational harbours, at São Miguel Island. Populations of three locally previously unknown barnacle species were found: Amphibalanus amphitrite, Amphibalanus eburneus and Perforatus perforatus. These species account for the more than 50% of alien barnacles worldwide that belong to Balanidae family. Hence, some considerations about morphology and life cycle of this family are advanced, discussed and related to their invasive potential.

aCORN Beta Spectrometer and Electrostatic Mirror

NASA Astrophysics Data System (ADS)

Hassan, Md; aCORN Collaboration

2013-10-01

aCORN uses a high efficiency backscatter suppressed beta spectrometer to measure the electron-antineutrino correlation in neutron beta decay. We measure the correlation by counting protons and beta electrons in coincidence with precisely determined electron energy. There are 19 photomultiplier tubes arranged in a hexagonal array coupled to a single phosphor doped polystyrene scintillator. The magnetic field is shaped so that electrons that backscatter without depositing their full energy strike a tulip-shaped array of scintillator paddles and these events are vetoed. The detailed construction, performance and calibration of this beta spectrometer will be presented. I will also present the simulation, construction, and features of our novel electrostatic mirror. This work was supported by the National Science Foundation and the NIST Center for Neutron Research.

The "Tears of the Virgin" at Lakes Entrance, southeast Australia were made by the intertidal barnacle Chthamalus antennatus (Cirripedia: Thoracica) and cyanobacteria.

PubMed

Buckeridge, John S; Newman, William A

2017-05-01

Curious eroded depressions, most resembling an eye shedding an elongate tear, are found in gently sloping, intertidal, carbonate-rich arenite outcropping on the sea coast near Lakes Entrance, Victoria, southeast Australia. The depressions, known locally as "Tears of the Virgin," are evidently formed by multiple generations of a barnacle, Chthamalus antennatus Darwin, 1854 in association with cyanobacteria. While the round part of a depression offers the barnacle a modicum of protection from impacts during high tides, it is also partially inhabited by cyanobacteria, which extend into and tend to fill the elongate tear. As such, this appears to be the first case of mutualism between a higher invertebrate and cyanobacteria, with the cyanobacteria reducing the barnacle's risk of desiccation while receiving metabolic wastes from it during low tides. It is also the first record of a balanomorph barnacle eroding calcareous arenite beneath its shell, the net effect of which would be expected to reduce its adhesion to the substrate. However, the siliceous residue, resulting from the barnacle's dissolution of the more than 80% of the calcite-rich sedimentary rock, is sequestered in delicate folds on the inside of the shell wall as it grows. A brief review of cirripedes capable of excavation includes the first photographic documentation of excavation of a mollusc shell by a verrucomorph. © 2016 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

Analysis of aquaporins from the euryhaline barnacle Balanus improvisus reveals differential expression in response to changes in salinity

PubMed Central

Järvå, Michael; Alm Rosenblad, Magnus; Pingitore, Piero; Karlsson, Emil; Wrange, Anna-Lisa; Kamdal, Emelie; Sundell, Kristina; André, Carl; Jonsson, Per R.; Havenhand, Jon; Eriksson, Leif A.; Hedfalk, Kristina; Blomberg, Anders

2017-01-01

Barnacles are sessile macro-invertebrates, found along rocky shores in coastal areas worldwide. The euryhaline bay barnacle Balanus improvisus (Darwin, 1854) (= Amphibalanus improvisus) can tolerate a wide range of salinities, but the molecular mechanisms underlying the osmoregulatory capacity of this truly brackish species are not well understood. Aquaporins are pore-forming integral membrane proteins that facilitate transport of water, small solutes and ions through cellular membranes, and that have been shown to be important for osmoregulation in many organisms. The knowledge of the function of aquaporins in crustaceans is, however, limited and nothing is known about them in barnacles. We here present the repertoire of aquaporins from a thecostracan crustacean, the barnacle B. improvisus, based on genome and transcriptome sequencing. Our analyses reveal that B. improvisus contains eight genes for aquaporins. Phylogenetic analysis showed that they represented members of the classical water aquaporins (Aqp1, Aqp2), the aquaglyceroporins (Glp1, Glp2), the unorthodox aquaporin (Aqp12) and the arthropod-specific big brain aquaporin (Bib). Interestingly, we also found two big brain-like proteins (BibL1 and BibL2) constituting a new group of aquaporins not yet described in arthropods. In addition, we found that the two water-specific aquaporins were expressed as C-terminal splice variants. Heterologous expression of some of the aquaporins followed by functional characterization showed that Aqp1 transported water and Glp2 water and glycerol, agreeing with the predictions of substrate specificity based on 3D modeling and phylogeny. To investigate a possible role for the B. improvisus aquaporins in osmoregulation, mRNA expression changes in adult barnacles were analysed after long-term acclimation to different salinities. The most pronounced expression difference was seen for AQP1 with a substantial (>100-fold) decrease in the mantle tissue in low salinity (3 PSU

Barnacles as biomonitors of trace metal availabilities in Hong Kong coastal waters: changes in space and time.

PubMed

Rainbow, P S; Blackmore, G

2001-06-01

The use of selected organisms as biomonitors of trace metal bioavailabilities allows comparisons to be made over space and time. The concentrations of 11 trace metals (arsenic, cadmium, chromium, cobalt, copper, iron, lead, manganese, nickel, silver, zinc) were measured in the bodies of two barnacle species, Balanus amphitrite and Tetraclita squamosa, from up to 18 littoral sites from Hong Kong coastal waters in April 1998. These data provide evidence on the geographical variation in metal bioavailabilities at this time, and are compared selectively against historical data sets for 1986 and 1989. Geographical variation in bioavailabilities is clear for several metals, with hotspots for arsenic, copper, nickel and silver at Chai Wan Kok, and for lead in Junk Bay. Victoria Harbour sites head the rankings for silver and arsenic, and Tolo Harbour sites exhibit relatively elevated cobalt, manganese and zinc. Many bioavailabilities of trace metals to barnacles are lower in Hong Kong coastal waters in 1998 than in 1986. The two barnacle species are widespread and the extensive data set presented is a benchmark which can be compared to the results of similar biomonitoring programmes elsewhere in the Indo-Pacific and beyond.

Acorn Production and Tree Growth of Nuttall Oak in a Green-Tree Reservoir

Treesearch

John K. Francis

1983-01-01

Green-tree reservoirs, created by flooding live timber stands, provide resting places and food for wintering waterfowl. The effects of winter flooding in terms of acorn production and growth of Nuttall oaks were studied in a reservoir which had been flooded annually for 15 years and in a nearby unflooded site. The study, which lasted for 5 years, included four tree...

Recruitment of the Intertidal Barnacle Semibalanus balanoides; Metamorphosis and Survival from Daily to Seasonal Timescales

DTIC Science & Technology

2008-09-01

before day 30 which corresponds to when the settlement distribution first switched from a positive to a negative correlation with adult abundance ...MLLW to control for tidal inundation, and we stratified quadrats onto most boulders distributed along a 20 meter shoreline at Gardiner beach (see...of 8 settlement plates that were situated between Gardiner beach and the rock wall, and not distributed at random as above, were outplanted before

Pin oak acorn production and regeneration as affected by stand density, structure and flooding

Treesearch

Leon S. Minckler; Robert E. McDermott

1960-01-01

Pin oak (Quercus palustris Muench.) is an important tree species common on wet, heavy soils in the Central States region. Until recently, however, the silvics of this species has been neglected (Minckler, 1957). In an effort to provide some of the missing information, a study was begun several years ago to find our more about pin oak acorn production...

Leaf Biomass and Acorn Production in a Thinned 30-Year-Old Cherrybark Oak Plantation

Treesearch

Erika L. Stelzer; Jim L. Chamgers; James S. Meadows; Kenneth F. Ribbeck

2004-01-01

Objectives of this study were to determine the effects of two levels of thinning on leaf biomass and acorn production of cherrybark oak (Quercus pagoda Raf.). To evaluate the effects of thinning 2 years after treatment, treatment plots were selected and blocked on the basis of initial stocking levels. Two levels of stocking and a control were...

A cross-sectional examination of the profile of chiropractors recruited to the Australian Chiropractic Research Network (ACORN): a sustainable resource for future chiropractic research.

PubMed

Adams, Jon; Peng, Wenbo; Steel, Amie; Lauche, Romy; Moore, Craig; Amorin-Woods, Lyndon; Sibbritt, David

2017-09-29

The Australian Chiropractic Research Network (ACORN) practice-based research network (PBRN) cohort was established to provide sustainable infrastructure necessary to address lack of rigorous investigation and to bridge the research-practice gap focused on chiropractic care for future years. This paper presents the profile of chiropractors recruited to the ACORN PBRN, a nationally representative sample of chiropractors working in Australia. Cross-sectional analysis of baseline data from a cohort study of chiropractors in Australia. All registered chiropractors in Australia were invited to participate in the ACORN study and those who completed a practitioner questionnaire and consent form were included in the PBRN cohort. A total of 1680 chiropractors (36%) were recruited to the cohort database. The average age of the PBRN participants is 41.9 years and 63% are male. The vast majority of the PBRN participants hold a university degree. General practitioners were identified as the most popular referral source for chiropractic care and low back pain and neck pain were the most common conditions 'often' treated by the PBRN chiropractors. The chiropractors in this PBRN cohort rated high velocity, low amplitude adjustment/manipulation/mobilisation as the most commonly used technique/method and soft tissue therapy as the most frequently employed musculoskeletal intervention in their patient management. The ACORN PBRN cohort constitutes the largest coverage of any single healthcare profession via a national voluntary PBRN providing a sustainable resource for future follow-up. The ACORN cohort provides opportunities for further nested substudies related to chiropractic care, chiropractors, their patients and a vast range of broader healthcare issues with a view to helping build a diverse but coordinated research programme and further research capacity building around Australian chiropractic. © Article author(s) (or their employer(s) unless otherwise stated in the text of the

Effects of Toxic Leachate from Commercial Plastics on Larval Survival and Settlement of the Barnacle Amphibalanus amphitrite.

PubMed

Li, Heng-Xiang; Getzinger, Gordon J; Ferguson, P Lee; Orihuela, Beatriz; Zhu, Mei; Rittschof, Daniel

2016-01-19

Plastic pollution represents a major and growing global problem. It is well-known that plastics are a source of chemical contaminants to the aquatic environment and provide novel habitats for marine organisms. The present study quantified the impacts of plastic leachates from the seven categories of recyclable plastics on larval survival and settlement of barnacle Amphibalanus (=Balanus) amphitrite. Leachates from plastics significantly increased barnacle nauplii mortality at the highest tested concentrations (0.10 and 0.50 m(2)/L). Hydrophobicity (measured as surface energy) was positively correlated with mortality indicating that plastic surface chemistry may be an important factor in the effects of plastics on sessile organisms. Plastic leachates significantly inhibited barnacle cyprids settlement on glass at all tested concentrations. Settlement on plastic surfaces was significantly inhibited after 24 and 48 h, but settlement was not significantly inhibited compared to the controls for some plastics after 72-96 h. In 24 h exposure to seawater, we found larval toxicity and inhibition of settlement with all seven categories of recyclable commercial plastics. Chemical analysis revealed a complex mixture of substances released in plastic leachates. Leaching of toxic compounds from all plastics should be considered when assessing the risks of plastic pollution.

Survival, growth, metallothionein and glycogen levels of Nucella lapillus (L.) exposed to subchronic cadmium stress: the influence of nutritional state and prey type.

PubMed

Leung, K M; Furness, R W

2001-08-01

Dogwhelks Nucella lapillus feed mainly on mussels and barnacles, and may experience periods of starvation. We report effects of nutritional state and prey type on the survival, growth, cadmium (Cd) accumulation, metallothionein (MT) induction and glycogen stores in N. lapillus exposed to Cd in water. Adult dogwhelks, with similar shell length (30.0+/-1.5 mm), were either starved or fed to satiation with barnacles Semibalanus balanoides, mussels Mytilus edulis or Cd-dosed M. edulis, and kept in filtered natural seawater (< 0.01 microg Cd 1(-1)) or Cd-contaminated (400 microg Cd 1(-1)) seawater for 80 days. Mortality and individual growth rate were determined. Cd, MT and glycogen were measured in different tissues. Prolonged starvation and exposure to Cd significantly reduced the survivorship of N. lapillus, but feeding could help dogwhelks to combat Cd toxicity and minimise mortality. Extended starvation also caused tissue wastage, leading to higher concentrations of Cd and MT in tissues, whereas fed animals increased in weight and had lower Cd and MT concentrations because of the tissue dilution effect. Prey type significantly affected growth rate of dogwhelks and indirectly influenced Cd accumulation, MT induction and glycogen stores. Eating mussels promoted better growth and higher glycogen reserves than eating barnacles. Individual growth rate decreased with increasing Cd accumulation. Cd-exposed survivors grew faster and consumed more than control animals, implying that these survivors may have better fitness and greater tolerance to Cd toxicity. The use of growth, condition index, MT and glycogen as biomarkers of environmental pollution are discussed. These results indicate a need to incorporate biological data including growth (or at least condition index) and prey type into biomonitoring programmes to allow sound interpretation.

Automated tracking and classification of the settlement behaviour of barnacle cyprids

PubMed Central

Aldred, Nick; Clare, Anthony S.

2017-01-01

A focus on the development of nontoxic coatings to control marine biofouling has led to increasing interest in the settlement behaviour of fouling organisms. Barnacles pose a significant fouling challenge and accordingly the behaviour of their settlement-stage cypris larva (cyprid) has attracted much attention, yet remains poorly understood. Tracking technologies have been developed that quantify cyprid movement, but none have successfully automated data acquisition over the prolonged periods necessary to capture and identify the full repertoire of behaviours, from alighting on a surface to permanent attachment. Here we outline a new tracking system and a novel classification system for identifying and quantifying the exploratory behaviour of cyprids. The combined system enables, for the first time, tracking of multiple larvae, simultaneously, over long periods (hours), followed by automatic classification of typical cyprid behaviours into swimming, wide search, close search and inspection events. The system has been evaluated by comparing settlement behaviour in the light and dark (infrared illumination) and tracking one of a group of 25 cyprids from the water column to settlement over the course of 5 h. Having removed a significant technical barrier to progress in the field, it is anticipated that the system will accelerate our understanding of the process of surface selection and settlement by barnacles. PMID:28356538

Effects of acorn size and mass on seedling quality of northern red oak (Quercus rubra)

Treesearch

Stacy L. Clark; Scott E. Schlarbaum

2018-01-01

Oaks are not sustainable in many upland temperate forests because of poor recruitment resulting from natural regeneration. Artificial regeneration is an alternative to natural regeneration, but is difficult, in part, due to large variation in seedling quality.  In this study, we examined the effects of acorn size and mass on nursery...

The effect of water temperature and flow on respiration in barnacles: patterns of mass transfer versus kinetic limitation.

PubMed

Nishizaki, Michael T; Carrington, Emily

2014-06-15

In aquatic systems, physiological processes such as respiration, photosynthesis and calcification are potentially limited by the exchange of dissolved materials between organisms and their environment. The nature and extent of physiological limitation is, therefore, likely to be dependent on environmental conditions. Here, we assessed the metabolic sensitivity of barnacles under a range of water temperatures and velocities, two factors that influence their distribution. Respiration rates increased in response to changes in temperature and flow, with an interaction where flow had less influence on respiration at low temperatures, and a much larger effect at high temperatures. Model analysis suggested that respiration is mass transfer limited under conditions of low velocity (<7.5 cm (-1)) and high temperature (20-25°C). In contrast, limitation by uptake reaction kinetics, when the biotic capacity of barnacles to absorb and process oxygen is slower than its physical delivery by mass transport, prevailed at high flows (40-150 cm s(-1)) and low temperatures (5-15°C). Moreover, there are intermediate flow-temperature conditions where both mass transfer and kinetic limitation are important. Behavioral monitoring revealed that barnacles fully extend their cirral appendages at low flows and display abbreviated 'testing' behaviors at high flows, suggesting some form of mechanical limitation. In low flow-high temperature treatments, however, barnacles displayed distinct 'pumping' behaviors that may serve to increase ventilation. Our results suggest that in slow-moving waters, respiration may become mass transfer limited as temperatures rise, whereas faster flows may serve to ameliorate the effects of elevated temperatures. Moreover, these results underscore the necessity for approaches that evaluate the combined effects of multiple environmental factors when examining physiological and behavioral performance. © 2014. Published by The Company of Biologists Ltd.

Barnacle Bill in Super Resolution from Super Panorama

NASA Image and Video Library

1998-07-03

"Barnacle Bill" is a small rock immediately west-northwest of the Mars Pathfinder lander and was the first rock visited by the Sojourner Rover's alpha proton X-ray spectrometer (APXS) instrument. This image shows super resolution techniques applied to the first APXS target rock, which was never imaged with the rover's forward cameras. Super resolution was applied to help to address questions about the texture of this rock and what it might tell us about its mode of origin. This view of Barnacle Bill was produced by combining the "Super Panorama" frames from the IMP camera. Super resolution was applied to help to address questions about the texture of these rocks and what it might tell us about their mode of origin. The composite color frames that make up this anaglyph were produced for both the right and left eye of the IMP. The composites consist of 7 frames in the right eye and 8 frames in the left eye, taken with different color filters that were enlarged by 500% and then co-added using Adobe Photoshop to produce, in effect, a super-resolution panchromatic frame that is sharper than an individual frame would be. These panchromatic frames were then colorized with the red, green, and blue filtered images from the same sequence. The color balance was adjusted to approximate the true color of Mars. The anaglyph view was produced by combining the left with the right eye color composite frames by assigning the left eye composite view to the red color plane and the right eye composite view to the green and blue color planes (cyan), to produce a stereo anaglyph mosaic. This mosaic can be viewed in 3-D on your computer monitor or in color print form by wearing red-blue 3-D glasses. http://photojournal.jpl.nasa.gov/catalog/PIA01409

Involvement of reactive oxygen species in the electrochemical inhibition of barnacle (Amphibalanus amphitrite) settlement

Treesearch

Rodolfo E. Perez-Roa; Marc A. Anderson; Dan Rittschof; Christopher G. Hunt; Daniel R. Noguera

2009-01-01

The role of reactive oxygen species (ROS) in electrochemical biofouling inhibition was investigated using a series of abiotic tests and settlement experiments with larvae of the barnacle Amphibalanus amphitrite, a cosmopolitan fouler. Larval settlement, a measure of biofouling potential, was reduced from 43% ± 14% to 5% ± 6% upon the application of...

Influence of weather at time of pollenation on acorn production of Quercus alba and Quercus velutina

Treesearch

Robert A. Cecich; Neal H. Sullivan

1999-01-01

Pistillate flower development and acorn production were observed in small populations of white oak (Quercus alba L.) and black oak (Quercus velurina Lam.) in central Missouri from 1990 to 1997. There were significant year-year differences in the size of flower crops for both species and significant tree-tree differences in black...

Patterns of distribution and abundance of the stalked barnacle (Pollicipes pollicipes) in the central and southwest coast of continental Portugal

NASA Astrophysics Data System (ADS)

Sousa, Alina; Jacinto, David; Penteado, Nélia; Martins, Pedro; Fernandes, Joana; Silva, Teresa; Castro, João J.; Cruz, Teresa

2013-10-01

The stalked barnacle Pollicipes pollicipes is a cirriped crustacean that lives on very exposed rocky shores. This barnacle is the most important economical resource on intertidal rocky shores of continental Portugal. It is highly prized as food and heavily exploited (professional and recreational fishery), but fishery data are scarce and do not estimate the real pressure upon this resource. Despite its socio-economic interest, specific regulations on this fishery are recent and different along the Portuguese coast. Four regions with different regulation can be identified: the marine reserve “Reserva Natural das Berlengas” (RNB) and the marine park “Parque Marinho Prof. Luiz Saldanha” (PMLS) (both in central Portugal); the natural park located in SW Portugal (“Parque Natural do Sudoeste Alentejano e Costa Vicentina”, PNSACV); and the rest of the coast. The main objective of the present study was to study the spatial patterns of percentage cover, biomass, density and size structure of P. pollicipes in areas with different exploitation regimes, including harvested areas and no-take areas. Additionally, variability between mid shore and low shore barnacles was also analysed. Seven areas were sampled with a variable number of sites (a total of 24) randomly sampled in each area during 2011. Photographs and image analysis (percentage cover) and destructive sampling (density, biomass and size) were used. In general, percentage cover, biomass and density were higher in mid shore when compared to low shore, namely in harvested areas. Low shore barnacles had a higher proportion of adults with moderate and high commercial value, while juveniles were relatively more abundant at mid shore. There were no consistent differences in the patterns of distribution and abundance of P. pollicipes among areas subject to different exploitation regimes. The most different area was the harvested area by professional fishers in RNB, where the highest biomass within the study was

The effect of small rodents on northern red oak acorns in north-central West Virginia

Treesearch

Linda S. Gribko; David M. Hix

1993-01-01

The effects of small mammals on surface-sown northern red oak (Quercus rubra) acorns was assessed in highly productive Appalachian hardwood stands. Study plots were established in October 1990 on excellent (average site index of 89 feet for red oak) and good (average site index of 72 feet) sites. Each plot included: 1) a rodent-proof exclosure, 2) an exclosure...

Effects of food availability on growth and reproduction of the deep-sea pedunculate barnacle Heteralepas canci

NASA Astrophysics Data System (ADS)

Yasuda, Natsumi; Miyamoto, Norio; Fujiwara, Yoshihiro; Yamamoto, Tomoko; Yusa, Yoichi

2016-02-01

Sessile animals living on continental shelves or slopes may adjust their growth and reproduction according to temporally and spatially variable food availability, but little information is available on these animals to date. We collected the pedunculate barnacle Heteralepas canci on a continental slope at a depth of 229 m off Cape Nomamisaki in southern Japan. We developed a rearing method for the barnacles and studied their growth and reproduction at different food levels in the laboratory. A total of 136 individual H. canci were fed with Artemia salina larvae and brewer's yeast at three different food levels for 100 days. Both the growth and the ovary development were delayed when food availability was low, whereas the survival rate was lower at the high food level. In addition, an individual survived under complete starvation for 167 days. We concluded that H. canci has plastic life history traits that are adaptive for variable food availability.

Effects of Flood Duration and Depth on Germination of Cherrybark, Post, Southern, White and Willow Oak Acorns

Treesearch

Yanfei Guo; Michael G. Shelton; Eric Heitzman

2002-01-01

Effects of flood duration (0, 10, 20, and 30 days) and depth (10 and 100 centimeters below a water surface) on acorn germination were tested for two bottomland oaks (cherrybark oak [Quercus pagoda Raf.] and willow oak [Q. phellos L.]) and three upland oaks (post oak [Q. stellata Wang.], southern red oak [

Antifouling Activity of Synthetic Alkylpyridinium Polymers Using the Barnacle Model

PubMed Central

Piazza, Veronica; Dragić, Ivanka; Sepčić, Kristina; Faimali, Marco; Garaventa, Francesca; Turk, Tom; Berne, Sabina

2014-01-01

Polymeric alkylpyridinium salts (poly-APS) isolated from the Mediterranean marine sponge, Haliclona (Rhizoniera) sarai, effectively inhibit barnacle larva settlement and natural marine biofilm formation through a non-toxic and reversible mechanism. Potential use of poly-APS-like compounds as antifouling agents led to the chemical synthesis of monomeric and oligomeric 3-alkylpyridinium analogues. However, these are less efficient in settlement assays and have greater toxicity than the natural polymers. Recently, a new chemical synthesis method enabled the production of poly-APS analogues with antibacterial, antifungal and anti-acetylcholinesterase activities. The present study examines the antifouling properties and toxicity of six of these synthetic poly-APS using the barnacle (Amphibalanus amphitrite) as a model (cyprids and II stage nauplii larvae) in settlement, acute and sub-acute toxicity assays. Two compounds, APS8 and APS12-3, show antifouling effects very similar to natural poly-APS, with an anti-settlement effective concentration that inhibits 50% of the cyprid population settlement (EC50) after 24 h of 0.32 mg/L and 0.89 mg/L, respectively. The toxicity of APS8 is negligible, while APS12-3 is three-fold more toxic (24-h LC50: nauplii, 11.60 mg/L; cyprids, 61.13 mg/L) than natural poly-APS. This toxicity of APS12-3 towards nauplii is, however, 60-fold and 1200-fold lower than that of the common co-biocides, Zn- and Cu-pyrithione, respectively. Additionally, exposure to APS12-3 for 24 and 48 h inhibits the naupliar swimming ability with respective IC50 of 4.83 and 1.86 mg/L. PMID:24699112

Changes and variations of polycyclic aromatic hydrocarbon concentrations in fish, barnacles and crabs following an oil spill in a mangrove of Guanabara Bay, Southeast Brazil.

PubMed

Soares-Gomes, Abílio; Neves, Roberta L; Aucélio, Ricardo; Van Der Ven, Paulo H; Pitombo, Fábio B; Mendes, Carla L T; Ziolli, Roberta L

2010-08-01

On April 26th, 2005, an accident caused a leak of 60,000L of Diesel Oil Type "B", freighted by train wagons upstream on a mangrove area within Guanabara Bay, Southeast Brazil. After the accident, samples from animals with different biological requirements were collected in order to monitor polycyclic aromatic hydrocarbons concentrations for the following 12months. Sessile, mobile, carnivorous, omnivorous, organic detritus feeders, planktivorous and suspension feeders were some of the attributes compared. Concentrations of PAHs did not vary in relation to different dietary habits and the best response was from the sessile suspensivorous barnacles. A background level of <50microgkg(-1) was suggested based on the reference site and on values observed in the following months after the accident. The highest values of PAH concentrations were observed in barnacles in the first month immediately after the spill, decreasing to background levels after few months. Barnacles are suggested as a sentinel species. Copyright 2010 Elsevier Ltd. All rights reserved.

Experimental winter warming modifies thermal performance and primes acorn ants for warm weather.

PubMed

MacLean, Heidi J; Penick, Clint A; Dunn, Robert R; Diamond, Sarah E

2017-07-01

The frequency of warm winter days is increasing under global climate change, but how organisms respond to warmer winters is not well understood. Most studies focus on growing season responses to warming. Locomotor performance is often highly sensitive to temperature, and can determine fitness outcomes through a variety of mechanisms including resource acquisition and predator escape. As a consequence, locomotor performance, and its impacts on fitness, may be strongly affected by winter warming in winter-active species. Here we use the acorn ant, Temnothorax curvispinosus, to explore how thermal performance (temperature-driven plasticity) in running speed is influenced by experimental winter warming of 3-5°C above ambient in a field setting. We used running speed as a measure of performance as it is a common locomotor trait that influences acquisition of nest sites and food in acorn ants. Experimental winter warming significantly altered thermal performance for running speed at high (26 and 36°C) but not low test temperatures (6 and 16°C). Although we saw little differentiation in thermal performance at cooler test temperatures, we saw a marked increase in running speed at the hotter test temperatures for ants that experienced warmer winters compared with those that experienced cooler winters. Our results provide evidence that overwintering temperatures can substantially influence organismal performance, and suggest that we cannot ignore overwintering effects when forecasting organismal responses to environmental changes in temperature. Copyright © 2017 Elsevier Ltd. All rights reserved.

Production of willow oak acorns in an Arkansas greentree reservoir: an evaluation of regeneration and waterfowl forage potential

Treesearch

M. R. Guttery; A. W. Ezell; J. D. Hodges; A. J. Londo; R. P. Maiers

2010-01-01

Greentree reservoirs (GTRs) provide critical habitat for a broad suite of species. Unfortunately, many GTRs are mismanaged, leading to undesirable successional changes and possible habitat degradation. This study evaluates willow oak acorn production in terms of the potential for natural regeneration and waterfowl forage. During the fall and winter of 2004 and 2005,...

Recalcitrant Behavior of Cherrybark Oak Seed: An FT-IR Study of Desiccation Sensitivity in Quercus pagoda Raf. Acorns

Treesearch

Sharon Sowa; Kristina F. Connor

2003-01-01

The recalcitrant behavior of cherrybark oak (Quercus pagoda Raf.) acorns was examined in terms of effects of moisture content on seed storage longevity and (short term) seed germination. Seed samples collected over two consecutive years were fully hydrated, then subjected to drying under ambient conditions of temperature and relative humidity on the...

Barnacle geese achieve significant energetic savings by changing posture.

PubMed

Tickle, Peter G; Nudds, Robert L; Codd, Jonathan R

2012-01-01

Here we report the resting metabolic rate in barnacle geese (Branta leucopsis) and provide evidence for the significant energetic effect of posture. Under laboratory conditions flow-through respirometry together with synchronous recording of behaviour enabled a calculation of how metabolic rate varies with posture. Our principal finding is that standing bipedally incurs a 25% increase in metabolic rate compared to birds sitting on the ground. In addition to the expected decrease in energy consumption of hindlimb postural muscles when sitting, we hypothesise that a change in breathing mechanics represents one potential mechanism for at least part of the observed difference in energetic cost. Due to the significant effect of posture, future studies of resting metabolic rates need to take into account and/or report differences in posture.

Effects of the Forest Floor and Acorn Placement on Establishment and Early Development of Water Oak Seedlings

Treesearch

Yanfei Guo; Michael G. Shelton; B.R. Lockhart

1999-01-01

Effects of the forest floor (0, 10, 20, 30,40, and 50 Mg/ha) and acorn placement (buried 1.5 cm below the soil surface, pressed into the soil surface, and placed within the forest floor) on establishment and early development of water oak (Quercus nigra L.) seedlings were tested in a 6 x 3 factorial study in southeastern Arkansas. Increasing...

Barnacle Geese Achieve Significant Energetic Savings by Changing Posture

PubMed Central

Tickle, Peter G.; Nudds, Robert L.; Codd, Jonathan R.

2012-01-01

Here we report the resting metabolic rate in barnacle geese (Branta leucopsis) and provide evidence for the significant energetic effect of posture. Under laboratory conditions flow-through respirometry together with synchronous recording of behaviour enabled a calculation of how metabolic rate varies with posture. Our principal finding is that standing bipedally incurs a 25% increase in metabolic rate compared to birds sitting on the ground. In addition to the expected decrease in energy consumption of hindlimb postural muscles when sitting, we hypothesise that a change in breathing mechanics represents one potential mechanism for at least part of the observed difference in energetic cost. Due to the significant effect of posture, future studies of resting metabolic rates need to take into account and/or report differences in posture. PMID:23071672

Disking and mid- and understory removal following an above-average acorn crop in three mature oak forests in southern Indiana

Treesearch

Ronald A. Rathfon; Nathanael I. Lichti; Robert K. Swihart

2008-01-01

We disked using small-scale equipment in the understory of three mature upland oak (Quercus) forests in southern Indiana immediately following acorn dispersal in an aboveaverage seed crop year as a means of improving oak seedling establishment. Three different mid- and understory removal treatments were also applied to create favorable light...

Molecular Characterization of the α-Subunit of Na+/K+ ATPase from the Euryhaline Barnacle Balanus improvisus Reveals Multiple Genes and Differential Expression of Alternative Splice Variants

PubMed Central

Lind, Ulrika; Alm Rosenblad, Magnus; Wrange, Anna-Lisa; Sundell, Kristina S.; Jonsson, Per R.; André, Carl; Havenhand, Jonathan; Blomberg, Anders

2013-01-01

The euryhaline bay barnacle Balanus improvisus has one of the broadest salinity tolerances of any barnacle species. It is able to complete its life cycle in salinities close to freshwater (3 PSU) up to fully marine conditions (35 PSU) and is regarded as one of few truly brackish-water species. Na+/K+ ATPase (NAK) has been shown to be important for osmoregulation when marine organisms are challenged by changing salinities, and we therefore cloned and examined the expression of different NAKs from B. improvisus. We found two main gene variants, NAK1 and NAK2, which were approximately 70% identical at the protein level. The NAK1 mRNA existed in a long and short variant with the encoded proteins differing only by 27 N-terminal amino acids. This N-terminal stretch was coded for by a separate exon, and the two variants of NAK1 mRNAs appeared to be created by alternative splicing. We furthermore showed that the two NAK1 isoforms were differentially expressed in different life stages and in various tissues of adult barnacle, i.e the long isoform was predominant in cyprids and in adult cirri. In barnacle cyprid larvae that were exposed to a combination of different salinities and pCO2 levels, the expression of the long NAK1 mRNA increased relative to the short in low salinities. We suggest that the alternatively spliced long variant of the Nak1 protein might be of importance for osmoregulation in B. improvisus in low salinity conditions. PMID:24130836

Intraspecific variation in the turtle barnacle, Cylindrolepas sinica Ren, 1980 (Cirripedia, Thoracica, Coronuloidea), with brief notes on habitat selectivity.

PubMed

Hayashi, Ryota

2013-01-01

Specimens of the turtle barnacle Cylindrolepas sinica Ren, 1980 were collected from sea turtles in Japanese waters. The specimens were hexagonal in shape and were found burrowing into the sea turtle plastron. Specimens were dissected and the hard and soft parts were compared with the original description.

The Interplay among Acorn Abundance and Rodent Behavior Drives the Spatial Pattern of Seedling Recruitment in Mature Mediterranean Oak Forests.

PubMed

Sunyer, Pau; Boixadera, Ester; Muñoz, Alberto; Bonal, Raúl; Espelta, Josep Maria

2015-01-01

The patterns of seedling recruitment in animal-dispersed plants result from the interactions among environmental and behavioral variables. However, we know little on the contribution and combined effect of both kinds of variables. We designed a field study to assess the interplay between environment (vegetation structure, seed abundance, rodent abundance) and behavior (seed dispersal and predation by rodents, and rooting by wild boars), and their contribution to the spatial patterns of seedling recruitment in a Mediterranean mixed-oak forest. In a spatially explicit design, we monitored intensively all environmental and behavioral variables in fixed points at a small spatial scale from autumn to spring, as well as seedling emergence and survival. Our results revealed that the spatial patterns of seedling emergence were strongly related to acorn availability on the ground, but not by a facilitation effect of vegetation cover. Rodents changed seed shadows generated by mother trees by dispersing most seeds from shrubby to open areas, but the spatial patterns of acorn dispersal/predation had no direct effect on recruitment. By contrast, rodents had a strong impact on recruitment as pilferers of cached seeds. Rooting by wild boars also reduced recruitment by reducing seed abundance, but also by changing rodent's behavior towards higher consumption of acorns in situ. Hence, seed abundance and the foraging behavior of scatter-hoarding rodents and wild boars are driving the spatial patterns of seedling recruitment in this mature oak forest, rather than vegetation features. The contribution of vegetation to seedling recruitment (e.g. facilitation by shrubs) may be context dependent, having a little role in closed forests, or being overridden by directed seed dispersal from shrubby to open areas. We warn about the need of using broad approaches that consider the combined action of environment and behavior to improve our knowledge on the dynamics of natural regeneration in

The Interplay among Acorn Abundance and Rodent Behavior Drives the Spatial Pattern of Seedling Recruitment in Mature Mediterranean Oak Forests

PubMed Central

Boixadera, Ester; Bonal, Raúl

2015-01-01

The patterns of seedling recruitment in animal-dispersed plants result from the interactions among environmental and behavioral variables. However, we know little on the contribution and combined effect of both kinds of variables. We designed a field study to assess the interplay between environment (vegetation structure, seed abundance, rodent abundance) and behavior (seed dispersal and predation by rodents, and rooting by wild boars), and their contribution to the spatial patterns of seedling recruitment in a Mediterranean mixed-oak forest. In a spatially explicit design, we monitored intensively all environmental and behavioral variables in fixed points at a small spatial scale from autumn to spring, as well as seedling emergence and survival. Our results revealed that the spatial patterns of seedling emergence were strongly related to acorn availability on the ground, but not by a facilitationeffect of vegetation cover. Rodents changed seed shadows generated by mother trees by dispersing most seeds from shrubby to open areas, but the spatial patterns of acorn dispersal/predation had no direct effect on recruitment. By contrast, rodents had a strong impact on recruitment as pilferers of cached seeds. Rooting by wild boars also reduced recruitment by reducing seed abundance, but also by changing rodent’s behavior towards higher consumption of acorns in situ. Hence, seed abundance and the foraging behavior of scatter-hoarding rodents and wild boars are driving the spatial patterns of seedling recruitment in this mature oak forest, rather than vegetation features. The contribution of vegetation to seedling recruitment (e.g. facilitation by shrubs) may be context dependent, having a little role in closed forests, or being overridden by directed seed dispersal from shrubby to open areas. We warn about the need of using broad approaches that consider the combined action of environment and behavior to improve our knowledge on the dynamics of natural regeneration in

Intraspecific variation in the turtle barnacle, Cylindrolepas sinica Ren, 1980 (Cirripedia, Thoracica, Coronuloidea), with brief notes on habitat selectivity

PubMed Central

Hayashi, Ryota

2013-01-01

Abstract Specimens of the turtle barnacle Cylindrolepas sinica Ren, 1980 were collected from sea turtles in Japanese waters. The specimens were hexagonal in shape and were found burrowing into the sea turtle plastron. Specimens were dissected and the hard and soft parts were compared with the original description. PMID:24167420

Effect of acorn mass and size, and early shoot growth on one-year old container-grown RPM™ oak seedlings

Treesearch

Benjamin C. Grossman; Michael A. Gold; Daniel C. Dey

2003-01-01

The purpose of this study was to evaluate the influence of seed source, acorn mass and size, and early shoot growth on morphological traits of 1-year-old oak seedlings. Forested bottomlands in the Midwest have been greatly reduced in the past 150 years as a result of conversion to agriculture and recent catastrophic floods. Due to a lack of available hard mast, intense...

Root development of acorn-origin oak seedlings in shelterwood stands on the Appalachian Plateau of northern Pennsylvania: 4-year results

Treesearch

Patrick H. Brose

2008-01-01

Post-fire sprouting of oak seedlings in prescribe-burned shelterwood stands hinges on their root collar diameters exceeding 6.4 mm and root size depends on the type of partial cut and the time since harvest. To better understand this shelterwood stage/time/oak root size relationship, a study was begun in northern Pennsylvania in 2001. Acorns of black, chestnut,...

Natal dispersal in the cooperatively breeding Acorn Woodpecker

USGS Publications Warehouse

Koenig, Walter D.; Hooge, P.N.; Stanback, M.T.; Haydock, J.

2000-01-01

Dispersal data are inevitably biased toward short-distance events, often highly so. We illustrate this problem using our long-term study of Acorn Woodpeckers (Melanerpes formicivorus) in central coastal California. Estimating the proportion of birds disappearing from the study area and correcting for detectability within the maximum observable distance are the first steps toward achieving a realistic estimate of dispersal distributions. Unfortunately, there is generally no objective way to determine the fates of birds not accounted for by these procedures, much less estimating the distances they may have moved. Estimated mean and root-mean-square dispersal distances range from 0.22-2.90 km for males and 0.53-9.57 km for females depending on what assumptions and corrections are made. Three field methods used to help correct for bias beyond the limits of normal study areas include surveying alternative study sites, expanding the study site (super study sites), and radio-tracking dispersers within a population. All of these methods have their limitations or can only be used in special cases. New technologies may help alleviate this problem in the near future. Until then, we urge caution in interpreting observed dispersal data from all but the most isolated of avian populations.

Third-Order Memristive Morris-Lecar Model of Barnacle Muscle Fiber

NASA Astrophysics Data System (ADS)

Rajamani, Vetriveeran; Sah, Maheshwar Pd.; Mannan, Zubaer Ibna; Kim, Hyongsuk; Chua, Leon

This paper presents a detailed analysis of various oscillatory behaviors observed in relation to the calcium and potassium ions in the third-order Morris-Lecar model of giant barnacle muscle fiber. Since, both the calcium and potassium ions exhibit all of the characteristics of memristor fingerprints, we claim that the time-varying calcium and potassium ions in the third-order Morris-Lecar model are actually time-invariant calcium and potassium memristors in the third-order memristive Morris-Lecar model. We confirmed the existence of a small unstable limit cycle oscillation in both the second-order and the third-order Morris-Lecar model by numerically calculating the basin of attraction of the asymptotically stable equilibrium point associated with two subcritical Hopf bifurcation points. We also describe a comprehensive analysis of the generation of oscillations in third-order memristive Morris-Lecar model via small-signal circuit analysis and a subcritical Hopf bifurcation phenomenon.

Evidence for the Involvement of p38 MAPK Activation in Barnacle Larval Settlement

PubMed Central

He, Li-Sheng; Xu, Ying; Matsumura, Kiyotaka; Zhang, Yu; Zhang, Gen; Qi, Shu-Hua; Qian, Pei-Yuan

2012-01-01

The barnacle Balanus ( = Amphibalanus) amphitrite is a major marine fouling animal. Understanding the molecular mechanism of larval settlement in this species is critical for anti-fouling research. In this study, we cloned one isoform of p38 MAPK (Bar-p38 MAPK) from this species, which shares the significant characteristic of containing a TGY motif with other species such as yeast, Drosophila and humans. The activation of p38 MAPK was detected by an antibody that recognizes the conserved dual phosphorylation sites of TGY. The results showed that phospho-p38 MAPK (pp38 MAPK) was more highly expressed at the cyprid stage, particularly in aged cyprids, in comparison to other stages, including the nauplius and juvenile stages. Immunostaining showed that Bar-p38 MAPK and pp38 MAPK were mainly located at the cyprid antennules, and especially the third and fourth segments, which are responsible for substratum exploration during settlement. The expression and localization patterns of Bar-p38 MAPK suggest its involvement in larval settlement. This postulation was also supported by the larval settlement bioassay with the p38 MAPK inhibitor SB203580. Behavioral analysis by live imaging revealed that the larvae were still capable of exploring the surface of the substratum after SB203580 treatment. This shows that the effect of p38 MAPK on larval settlement might be by regulating the secretion of permanent proteinaceous substances. Furthermore, the level of pp38 MAPK dramatically decreased after full settlement, suggesting that Bar-p38 MAPK maybe plays a role in larval settlement rather than metamorphosis. Finally, we found that Bar-p38 MAPK was highly activated when larvae confronted extracts of adult barnacle containing settlement cues, whereas larvae pre-treated with SB203580 failed to respond to the crude adult extracts. PMID:23115639

Comparative Transcriptomic Analysis Reveals Candidate Genes and Pathways Involved in Larval Settlement of the Barnacle Megabalanus volcano.

PubMed

Yan, Guoyong; Zhang, Gen; Huang, Jiaomei; Lan, Yi; Sun, Jin; Zeng, Cong; Wang, Yong; Qian, Pei-Yuan; He, Lisheng

2017-10-27

Megabalanus barnacle is one of the model organisms for marine biofouling research. However, further elucidation of molecular mechanisms underlying larval settlement has been hindered due to the lack of genomic information thus far. In the present study, cDNA libraries were constructed for cyprids, the key stage for larval settlement, and adults of Megabalanus volcano . After high-throughput sequencing and de novo assembly, 42,620 unigenes were obtained with a N50 value of 1532 bp. These unigenes were annotated by blasting against the NCBI non-redundant (nr), Swiss-Prot, Cluster of Orthologous Groups (COG), and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. Finally, 19,522, 15,691, 14,459, and 10,914 unigenes were identified correspondingly. There were 22,158 differentially expressed genes (DEGs) identified between two stages. Compared with the cyprid stage, 8241 unigenes were down-regulated and 13,917 unigenes were up-regulated at the adult stage. The neuroactive ligand-receptor interaction pathway (ko04080) was significantly enriched by KEGG enrichment analysis of the DEGs, suggesting that it possibly involved in larval settlement. Potential functions of three conserved allatostatin neuropeptide-receptor pairs and two light-sensitive opsin proteins were further characterized, indicating that they might regulate attachment and metamorphosis at cyprid stage. These results provided a deeper insight into the molecular mechanisms underlying larval settlement of barnacles.

Comparative Transcriptomic Analysis Reveals Candidate Genes and Pathways Involved in Larval Settlement of the Barnacle Megabalanus volcano

PubMed Central

Yan, Guoyong; Huang, Jiaomei; Lan, Yi; Zeng, Cong; Wang, Yong; Qian, Pei-Yuan; He, Lisheng

2017-01-01

Megabalanus barnacle is one of the model organisms for marine biofouling research. However, further elucidation of molecular mechanisms underlying larval settlement has been hindered due to the lack of genomic information thus far. In the present study, cDNA libraries were constructed for cyprids, the key stage for larval settlement, and adults of Megabalanus volcano. After high-throughput sequencing and de novo assembly, 42,620 unigenes were obtained with a N50 value of 1532 bp. These unigenes were annotated by blasting against the NCBI non-redundant (nr), Swiss-Prot, Cluster of Orthologous Groups (COG), and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. Finally, 19,522, 15,691, 14,459, and 10,914 unigenes were identified correspondingly. There were 22,158 differentially expressed genes (DEGs) identified between two stages. Compared with the cyprid stage, 8241 unigenes were down-regulated and 13,917 unigenes were up-regulated at the adult stage. The neuroactive ligand-receptor interaction pathway (ko04080) was significantly enriched by KEGG enrichment analysis of the DEGs, suggesting that it possibly involved in larval settlement. Potential functions of three conserved allatostatin neuropeptide-receptor pairs and two light-sensitive opsin proteins were further characterized, indicating that they might regulate attachment and metamorphosis at cyprid stage. These results provided a deeper insight into the molecular mechanisms underlying larval settlement of barnacles. PMID:29077039

Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia)

PubMed Central

Chan, Benny K. K.; Chen, H. -N.; Dando, P. R.; Southward, A. J.; Southward, E. C.

2016-01-01

The biogeography and ecology of the species of Chthamalus present on the west coast of America are described, using data from 51 localities from Alaska to Panama, together with their zonation on the shore with respect to that of other barnacles. The species present were C. dalli, Pilsbry 1916, C. fissus, Darwin, 1854, C. anisopoma Pilsbry 1916 and four species in the C. panamensis complex. The latter are C. panamensis Pilsbry, 1916, C. hedgecocki, Pitombo & Burton, 2007, C. alani nom. nov. (formerly C. southwardorum Pitombo & Burton, 2007) and C. newmani sp. nov.). These four species were initially separated by enzyme electrophoresis. They could only be partially separated by DNA bar coding but may be separated using morphological characters. PMID:26958842

Sodium and Potassium Fluxes in Isolated Barnacle Muscle Fibers

PubMed Central

Brinley, F. J.

1968-01-01

Sodium and potassium influxes and outfluxes have been studied in single isolated muscle fibers from the giant barnacle both by microinjection and by external loading. The sodium influxes and outfluxes were 49 and 39 pmoles /cm2-sec (temperature = 15–16°C) respectively. The potassium influxes and outfluxes were 28 and 60 pmoles/cm2-sec (temperature = 13–16°C) respectively. Replacement of external sodium by lithium reduced sodium outflux by 67% but had no effect on potassium outflux. Removal of external potassum reduced the sodium outflux by 51% but had no effect on potassium outflux. External strophanthidin (10–30 µM) reduced sodium outflux by 80–90% and increased potassium outflux by 40% in normal fibers. The time constant for sodium exchange increased linearly with internal sodium concentration, as did the fraction of sodium outflux insensitive to a maximally inhibitory concentration of external strophanthidin in the range of 10 tO 80 mM internal sodium. The strophanthidin-sensitive component of sodium outflux could be related to the internal sodium concentration by the following empirical formula: See PDF for Equation PMID:5651768

Chloride Fluxes in Isolated Dialyzed Barnacle Muscle Fibers

PubMed Central

DiPolo, R.

1972-01-01

Chloride outflux and influx has been studied in single isolated muscle fibers from the giant barnacle under constant internal composition by means of a dialysis perfusion technique. Membrane potential was continually recorded. The chloride outfluxes and influxes were 143 and 144 pmoles/cm2-sec (mean resting potential: 58 mv, temperature: 22°–24°C) with internal and external chloride concentrations of 30 and 541 mM, respectively. The chloride conductance calculated from tracer measurements using constant field assumptions is about fourfold greater than that calculated from published electrical data. Replacing 97% of the external chloride ions by propionate reduces the chloride efflux by 51%. Nitrate ions applied either to the internal or external surface of the membrane slows the chloride efflux. The external pH dependence of the chloride efflux follows the external pH dependence of the membrane conductance, in the range pH 3.9–4.7, increasing with decreasing pH. In the range pH 5–9, the chloride efflux increased with increasing pH, in a manner similar to that observed in frog muscle fibers. The titration curve for internal pH changes in the range 4.0–7.0 was quantitatively much different from that for external pH change, indicating significant asymmetry in the internal and external pH dependence of the chloride efflux. PMID:5074810

The Story of a Hitchhiker: Population Genetic Patterns in the Invasive Barnacle Balanus(Amphibalanus) improvisus Darwin 1854

PubMed Central

Wrange, Anna-Lisa; Charrier, Gregory; Thonig, Anne; Alm Rosenblad, Magnus; Blomberg, Anders; Havenhand, Jonathan N.; Jonsson, Per R.; André, Carl

2016-01-01

Understanding the ecological and evolutionary forces that determine the genetic structure and spread of invasive species is a key component of invasion biology. The bay barnacle, Balanus improvisus (= Amphibalanus improvisus), is one of the most successful aquatic invaders worldwide, and is characterised by broad environmental tolerance. Although the species can spread through natural larval dispersal, human-mediated transport through (primarily) shipping has almost certainly contributed to the current global distribution of this species. Despite its worldwide distribution, little is known about the phylogeography of this species. Here, we characterize the population genetic structure and model dispersal dynamics of the barnacle B. improvisus, and describe how human-mediated spreading via shipping as well as natural larval dispersal may have contributed to observed genetic variation. We used both mitochondrial DNA (cytochrome c oxidase subunit I: COI) and nuclear microsatellites to characterize the genetic structure in 14 populations of B. improvisus on a global and regional scale (Baltic Sea). Genetic diversity was high in most populations, and many haplotypes were shared among populations on a global scale, indicating that long-distance dispersal (presumably through shipping and other anthropogenic activities) has played an important role in shaping the population genetic structure of this cosmopolitan species. We could not clearly confirm prior claims that B. improvisus originates from the western margins of the Atlantic coasts; although there were indications that Argentina could be part of a native region. In addition to dispersal via shipping, we show that natural larval dispersal may play an important role for further colonisation following initial introduction. PMID:26821161

Characterization of cement float buoyancy in the stalked barnacle Dosima fascicularis (Crustacea, Cirripedia).

PubMed

Zheden, Vanessa; Kovalev, Alexander; Gorb, Stanislav N; Klepal, Waltraud

2015-02-06

Dosima fascicularis is the only barnacle which can drift autonomously at the water surface with a foam-like cement float. The cement secreted by the animal contains numerous gas-filled cells of different size. When several individuals share one float, their size and not their number is crucial for the production of both volume and mass of the float. The gas content within the cells of the foam gives positive static buoyancy to the whole float. The volume of the float, the gas volume and the positive static buoyancy are positively correlated. The density of the cement float without gas is greater than that of seawater. This study shows that the secreted cement consists of more than 90% water and the gas volume is on average 18.5%. Our experiments demonstrate that the intact foam-like cement float is sealed to the surrounding water.

Characterization of cement float buoyancy in the stalked barnacle Dosima fascicularis (Crustacea, Cirripedia)

PubMed Central

Zheden, Vanessa; Kovalev, Alexander; Gorb, Stanislav N.; Klepal, Waltraud

2015-01-01

Dosima fascicularis is the only barnacle which can drift autonomously at the water surface with a foam-like cement float. The cement secreted by the animal contains numerous gas-filled cells of different size. When several individuals share one float, their size and not their number is crucial for the production of both volume and mass of the float. The gas content within the cells of the foam gives positive static buoyancy to the whole float. The volume of the float, the gas volume and the positive static buoyancy are positively correlated. The density of the cement float without gas is greater than that of seawater. This study shows that the secreted cement consists of more than 90% water and the gas volume is on average 18.5%. Our experiments demonstrate that the intact foam-like cement float is sealed to the surrounding water. PMID:25657839

Density drives polyandry and relatedness influences paternal success in the Pacific gooseneck barnacle, Pollicipes elegans.

PubMed

Plough, Louis V; Moran, Amy; Marko, Peter

2014-04-16

Polyandry is a common mating strategy in animals, increasing female fitness through direct (material) and indirect (genetic) benefits. Most theories about the benefits of polyandry come from studies of terrestrial animals, which have relatively complex mating systems and behaviors; less is known about the potential benefits of polyandry in sessile marine animals, for which potential mates may be scarce and females have less control over pre-copulatory mate choice. Here, we used microsatellite markers to examine multiple paternity in natural aggregations of the Pacific gooseneck barnacle Pollicipes elegans, testing the effect of density on paternity and mate relatedness on male reproductive success. We found that multiple paternity was very common (79% of broods), with up to five fathers contributing to a brood, though power was relatively low to detect more than four fathers. Density had a significant and positive linear effect on the number of fathers siring a brood, though this relationship leveled off at high numbers of fathers, which may reflect a lack of power and/or an upper limit to polyandry in this species. Significant skew in male reproductive contribution in multiply-sired broods was observed and we found a positive and significant relationship between the proportion of offspring sired and the genetic similarity between mates, suggesting that genetic compatibility may influence reproductive success in this species. To our knowledge, this is the first study to show high levels of multiple paternity in a barnacle, and overall, patterns of paternity in P. elegans appear to be driven primarily by mate availability. Evidence of paternity bias for males with higher relatedness suggests some form of post-copulatory sexual selection is taking place, but more work is needed to determine whether it operates during or post-fertilization. Overall, our results suggest that while polyandry in P. elegans is driven by mate availability, it may also provide a mechanism

Density drives polyandry and relatedness influences paternal success in the Pacific gooseneck barnacle, Pollicipes elegans

PubMed Central

2014-01-01

Background Polyandry is a common mating strategy in animals, increasing female fitness through direct (material) and indirect (genetic) benefits. Most theories about the benefits of polyandry come from studies of terrestrial animals, which have relatively complex mating systems and behaviors; less is known about the potential benefits of polyandry in sessile marine animals, for which potential mates may be scarce and females have less control over pre-copulatory mate choice. Here, we used microsatellite markers to examine multiple paternity in natural aggregations of the Pacific gooseneck barnacle Pollicipes elegans, testing the effect of density on paternity and mate relatedness on male reproductive success. Results We found that multiple paternity was very common (79% of broods), with up to five fathers contributing to a brood, though power was relatively low to detect more than four fathers. Density had a significant and positive linear effect on the number of fathers siring a brood, though this relationship leveled off at high numbers of fathers, which may reflect a lack of power and/or an upper limit to polyandry in this species. Significant skew in male reproductive contribution in multiply-sired broods was observed and we found a positive and significant relationship between the proportion of offspring sired and the genetic similarity between mates, suggesting that genetic compatibility may influence reproductive success in this species. Conclusions To our knowledge, this is the first study to show high levels of multiple paternity in a barnacle, and overall, patterns of paternity in P. elegans appear to be driven primarily by mate availability. Evidence of paternity bias for males with higher relatedness suggests some form of post-copulatory sexual selection is taking place, but more work is needed to determine whether it operates during or post-fertilization. Overall, our results suggest that while polyandry in P. elegans is driven by mate availability, it

Comparative analysis of Cucurbita pepo metabolism throughout fruit development in acorn squash and oilseed pumpkin

PubMed Central

Wyatt, Lindsay E; Strickler, Susan R; Mueller, Lukas A; Mazourek, Michael

2016-01-01

Both the fruit mesocarp and the seeds of winter squash can be used for consumption, although the focus of breeding efforts varies by cultivar. Cultivars bred for fruit consumption are selected for fruit mesocarp quality traits such as carotenoid content, percent dry matter, and percent soluble solids, while these traits are essentially ignored in oilseed pumpkins. To compare fruit development in these two types of squash, we sequenced the fruit transcriptome of two cultivars bred for different purposes: an acorn squash, ‘Sweet REBA’, and an oilseed pumpkin, ‘Lady Godiva’. Putative metabolic pathways were developed for carotenoid, starch, and sucrose synthesis in winter squash fruit and squash homologs were identified for each of the structural genes in the pathways. Gene expression, especially of known rate-limiting and branch point genes, corresponded with metabolite accumulation both across development and between the two cultivars. Thus, developmental regulation of metabolite genes is an important factor in winter squash fruit quality. PMID:27688889

The whale barnacle Cryptolepas rhachianecti (Cirripedia: Coronulidae), a phoront of the grey whale Eschrichtius robustus (Cetacea: Eschrichtiidae), from a sandy beach in The Netherlands.

PubMed

Bosselaers, Mark; Collareta, Alberto

2016-08-22

An isolated compartment of a whale barnacle is herein described from Recent beach deposits in Zoutelande (Walcheren, The Netherlands). This specimen is identified as belonging to the extant coronulid species Cryptolepas rhachianecti, currently known as an epizoic symbiont of the grey whale Eschrichtius robustus. This find represents the first occurrence of C. rhachianecti outside the North Pacific, and the first one as a (sub)fossil. In view of the fact that E. robustus, which is currently confined to the North Pacific, is known as a subfossil from the northeastern Atlantic between late Late Pleistocene (c. 45,000 years ago) and historical (c. 1700 AD) times, we propose a similar (late Quaternary) age for the isolated compartment. The find indicates that the extinct late Quaternary northeastern Atlantic population of E. robustus was infected by Cryptolepas rhachianecti. Our find is, therefore, compatible with the hypothesis of an ancient grey whale migration route running between the subtropical/temperate waters of the northeast Atlantic (or Mediterranean Basin), and the cold waters of the Baltic Sea (or southern Arctic Ocean), through the southern North Sea. Finally, we discuss the systematic placement of the fossil barnacle species Cryptolepas murata and propose the possibility of its removal from the genus Cryptolepas pending further investigations.

Preparation and characterization of activated carbon from acorn shell by physical activation with H2O-CO2 in two-step pretreatment.

PubMed

Şahin, Ömer; Saka, Cafer

2013-05-01

Activated carbons have been prepared by physical activation with H2O-CO2 in two-step pre-treatment including ZnCl2-HCl from acorn shell at 850 °C. The active carbons were characterized by N2 adsorption at 77 K. Adsorption capacity was demonstrated by the iodine numbers. The surface chemical characteristics of activated carbons were determined by FTIR spectroscopic method. The microstructure of the activated carbons prepared was examined by scanning electron microscopy. The maximum BET surface area of the obtained activated carbon was found to be around 1779 m(2)/g. Copyright © 2013 Elsevier Ltd. All rights reserved.

Hot limpets: predicting body temperature in a conductance-mediated thermal system.

PubMed

Denny, Mark W; Harley, Christopher D G

2006-07-01

Living at the interface between the marine and terrestrial environments, intertidal organisms may serve as a bellwether for environmental change and a test of our ability to predict its biological consequences. However, current models do not allow us to predict the body temperature of intertidal organisms whose heat budgets are strongly affected by conduction to and from the substratum. Here, we propose a simple heat-budget model of one such animal, the limpet Lottia gigantea, and test the model against measurements made in the field. Working solely from easily measured physical and meteorological inputs, the model predicts the daily maximal body temperatures of live limpets within a fraction of a degree, suggesting that it may be a useful tool for exploring the thermal biology of limpets and for predicting effects of climate change. The model can easily be adapted to predict the temperatures of chitons, acorn barnacles, keyhole limpets, and encrusting animals and plants.

Microsatellite loci discovery from next-generation sequencing data and loci characterization in the epizoic barnacle Chelonibia testudinaria (Linnaeus, 1758)

PubMed Central

Zardus, John D.; Wares, John P.

2016-01-01

Microsatellite markers remain an important tool for ecological and evolutionary research, but are unavailable for many non-model organisms. One such organism with rare ecological and evolutionary features is the epizoic barnacle Chelonibia testudinaria (Linnaeus, 1758). Chelonibia testudinaria appears to be a host generalist, and has an unusual sexual system, androdioecy. Genetic studies on host specificity and mating behavior are impeded by the lack of fine-scale, highly variable markers, such as microsatellite markers. In the present study, we discovered thousands of new microsatellite loci from next-generation sequencing data, and characterized 12 loci thoroughly. We conclude that 11 of these loci will be useful markers in future ecological and evolutionary studies on C. testudinaria. PMID:27231653

Effects of spatial structure of population size on the population dynamics of barnacles across their elevational range.

PubMed

Fukaya, Keiichi; Okuda, Takehiro; Nakaoka, Masahiro; Noda, Takashi

2014-11-01

Explanations for why population dynamics vary across the range of a species reflect two contrasting hypotheses: (i) temporal variability of populations is larger in the centre of the range compared to the margins because overcompensatory density dependence destabilizes population dynamics and (ii) population variability is larger near the margins, where populations are more susceptible to environmental fluctuations. In both of these hypotheses, positions within the range are assumed to affect population variability. In contrast, the fact that population variability is often related to mean population size implies that the spatial structure of the population size within the range of a species may also be a useful predictor of the spatial variation in temporal variability of population size over the range of the species. To explore how population temporal variability varies spatially and the underlying processes responsible for the spatial variation, we focused on the intertidal barnacle Chthamalus dalli and examined differences in its population dynamics along the tidal levels it inhabits. Changes in coverage of barnacle populations were monitored for 10.5 years at 25 plots spanning the elevational range of this species. Data were analysed by fitting a population dynamics model to estimate the effects of density-dependent and density-independent processes on population growth. We also examined the temporal mean-variance relationship of population size with parameters estimated from the population dynamics model. We found that the relative variability of populations tended to increase from the centre of the elevational range towards the margins because of an increase in the magnitude of stochastic fluctuations of growth rates. Thus, our results supported hypothesis (2). We also found that spatial variations in temporal population variability were well characterized by Taylor's power law, the relative population variability being inversely related to the mean

Importance of plasticity and local adaptation for coping with changing salinity in coastal areas: a test case with barnacles in the Baltic Sea

PubMed Central

2014-01-01

Background Salinity plays an important role in shaping coastal marine communities. Near-future climate predictions indicate that salinity will decrease in many shallow coastal areas due to increased precipitation; however, few studies have addressed this issue. The ability of ecosystems to cope with future changes will depend on species’ capacities to acclimatise or adapt to new environmental conditions. Here, we investigated the effects of a strong salinity gradient (the Baltic Sea system – Baltic, Kattegat, Skagerrak) on plasticity and adaptations in the euryhaline barnacle Balanus improvisus. We used a common-garden approach, where multiple batches of newly settled barnacles from each of three different geographical areas along the Skagerrak-Baltic salinity gradient were exposed to corresponding native salinities (6, 15 and 30 PSU), and phenotypic traits including mortality, growth, shell strength, condition index and reproductive maturity were recorded. Results We found that B. improvisus was highly euryhaline, but had highest growth and reproductive maturity at intermediate salinities. We also found that low salinity had negative effects on other fitness-related traits including initial growth and shell strength, although mortality was also lowest in low salinity. Overall, differences between populations in most measured traits were weak, indicating little local adaptation to salinity. Nonetheless, we observed some population-specific responses – notably that populations from high salinity grew stronger shells in their native salinity compared to the other populations, possibly indicating adaptation to differences in local predation pressure. Conclusions Our study shows that B. improvisus is an example of a true brackish-water species, and that plastic responses are more likely than evolutionary tracking in coping with future changes in coastal salinity. PMID:25038588

Preparation and characterization of acorn starch/poly(lactic acid) composites modified with functionalized vegetable oil derivates.

PubMed

Li, Shouhai; Xia, Jianling; Xu, Yuzhi; Yang, Xuejuan; Mao, Wei; Huang, Kun

2016-05-20

Composites of acorn starch (AS) and poly(1actic acid) (PLA) modified with dimer fatty acid (DFA) or dimer fatty acid polyamide (DFAPA) were produced by a hot-melt extrusion method. The effects of DFA and DFAPA contents on the mechanical, hydrophobic, thermal properties and melt fluidity of the composites were studied under an invariable AS-to-PLA mass ratio of 40/60. SEM and DMA research results show that the compatibility of AS/PLA composites are determined by the dosage of DFA or DFAPA. The hydrophobicity and melt fluidity of composites are improved with the addition of DFA and DFAPA. The glass transition temperatures of the composites are all reduced remarkably by additives DFA and DFAPA. However, DFA and DFAPA exert different effects on the mechanical properties of AS/PLA composites. In the DFAPA-modified system, the tensile and flexural strength first increase and then decrease with the increase of DFAPA dosage; the mechanical strength is maximized when the dosage of DFAPA is 2 wt% of total weight. In the DFA-modified system, the tensile and flexural strength decrease with the increase of DFA dosage. Copyright © 2016 Elsevier Ltd. All rights reserved.

The state of the fishery, conservation and management of the stalked barnacle Pollicipes pollicipes in Portugal.

PubMed

Cruz, Teresa; Jacinto, David; Sousa, Alina; Penteado, Nélia; Pereira, Diana; Fernandes, Joana N; Silva, Teresa; Castro, João J

2015-12-01

The stalked barnacle Pollicipes pollicipes is the most important intertidal economical resource in Portugal. The assessment of the state of the fishery, conservation and management of P. pollicipes in Portugal was made for the first time in three regions with different regulations regarding this fishery: two marine protected areas ("Reserva Natural das Berlengas", RNB; and "Parque Natural do Sudoeste Alentejano e Costa Vicentina", PNSACV); and the Center coast. Different approaches (independent observations, inquiries, logbooks) and sources of data (past and recent) were used. An overall negative tendency of the state of the fishery and conservation of this resource was observed in all regions, with the exception of the stable tendency detected in PNSACV when using the inquiries approach. A weak management was considered to be in practice at Center and at PNSACV, while an acceptable management was inferred for RNB. We recommend a change into a co-management system that should be tested in pilot regions as RNB and/or PNSACV. Copyright © 2015 Elsevier Ltd. All rights reserved.

Adsorption of intrinsically disordered barnacle adhesive proteins on silica surface

NASA Astrophysics Data System (ADS)

Wang, Xiaoqiang; Wang, Chao; Xu, Baomei; Wei, Junting; Xiao, Yang; Huang, Fang

2018-01-01

The adsorption of recombinant barnacle proteins Bacp19k and Mrcp19k on hydrophilic silica surface was characterized by spectroscopic ellipsometry in artificial seawater (pH = 8.2). They are homologous adhesive proteins destined for underwater adhesion but bear opposite net charges in seawater. As assessed with their primary and secondary structures, both proteins are intrinsically disordered and thus distinct from globular proteins that have dominated research in the field. Different from Mrcp19k, higher initial rate and adsorbed amount were obtained via curve fitting for Bacp19k in kinetic studies, due to favorable charge interactions with silica surface. The good fitting with the same dynamic model also indicates the formation of monolayer coverage in both cases. The two adsorption isotherms of Bacp19k and Mrcp19k are different in the initial change and maximum adsorption level, indicating different protein-surface affinities and charge interactions. Each isotherm fits the Langmuir model well, which is commonly used to describe monolayer adsorption, thus consistent with the predication from kinetic fitting. To further examine the effect of electrostatic interaction on the adsorption, the isotherm of the 1:1 mixture of Bacp19k and Mrcp19k was also constructed, which showed a higher correlation fit for Jovanovic than for Langmuir model. The presence of electrostatic attraction between Bacp19k and Mrcp19k deviated from one of the required conditions for Langmuir behavior, which may also result in the highest coadsorption level but slowest initial change among the three isotherms. The surface state of the adhesive proteins and the change with adsorption time were also examined by atomic force microscopy. The results thus obtained are in good agreement with the corresponding ellipsometric measurement.

Diel pattern of corticosterone metabolites in Arctic barnacle goslings (Branta leucopsis) under continuous natural light

PubMed Central

de Jong, Margje E.; Komdeur, Jan; Pschernig, Elisabeth; Loonen, Maarten J. J. E.; Millesi, Eva; Weiß, Brigitte M.

2017-01-01

Here we describe the excretion pattern of corticosterone metabolites collected from droppings in barnacle goslings (Branta leucopsis) raised under 24 hours of continuous natural light in the Arctic. In lower latitudes, circulating corticosterone peaks around waking and shows a nadir between midnight and 4:00, whereas the peak and nadir are time-delayed slightly when measuring corticosterone metabolites from droppings. Photoperiod, along with other environmental factors, helps to entrain an animal’s endogenous rhythm to that of the natural world. North of the Arctic Circle, photoperiod may not be a reliable cue as light is continuously absent during the winter and continuously present during the summer. Here, for the first time, we used droppings to describe a 24-hour excretion pattern of corticosterone metabolites (CORTm). By applying circular statistics for dependent data, we found a diel rhythmic pattern even under continuous natural light. We discuss potential alternative ‘Zeitgeber’ that may function even in the polar regions, focusing on melatonin. We propose a line of research to measure melatonin non-invasively from droppings. We also provide a validation of the adopted enzyme immunoassay (EIA) that was originally developed for greylag geese. PMID:28787012

Natural Underwater Adhesives

PubMed Central

Stewart, Russell J.; Ransom, Todd C.; Hlady, Vladimir

2011-01-01

The general topic of this review is protein-based underwater adhesives produced by aquatic organisms. The focus is on mechanisms of interfacial adhesion to native surfaces and controlled underwater solidification of natural water-borne adhesives. Four genera that exemplify the broad range of function, general mechanistic features, and unique adaptations are discussed in detail: blue mussels, acorn barnacles, sandcastle worms, and freshwater caddisfly larva. Aquatic surfaces in nature are charged and in equilibrium with their environment, populated by an electrical double layer of ions as well as adsorbed natural polyelectrolytes and microbial biofilms. Surface adsorption of underwater bioadhesives likely occurs by exchange of surface bound ligands by amino acid sidechains, driven primarily by relative affinities and effective concentrations of polymeric functional groups. Most aquatic organisms exploit modified amino acid sidechains, in particular phosphorylated serines and hydroxylated tyrosines (dopa), with high-surface affinity that form coordinative surface complexes. After delivery to the surfaces as a fluid, permanent natural adhesives solidify to bear sustained loads. Mussel plaques are assembled in a manner superficially reminiscent of in vitro layer-by-layer strategies, with sequentially delivered layers associated through Fe(dopa)3 coordination bonds. The adhesives of sandcastle worms, caddisfly larva, and barnacles may be delivered in a form somewhat similar to in vitro complex coacervation. Marine adhesives are secreted, or excreted, into seawater that has a significantly higher pH and ionic strength than the internal environment. Empirical evidence suggests these environment triggers could provide minimalistic, fail-safe timing mechanisms to prevent premature solidification (insolubilization) of the glue within the secretory system, yet allow rapid solidification after secretion. Underwater bioadhesives are further strengthened by secondary covalent

Biomonitoring of trace metal bioavailabilities to the barnacle Amphibalanus amphitrite along the Iranian coast of the Persian Gulf.

PubMed

Nasrolahi, A; Smith, B D; Ehsanpour, M; Afkhami, M; Rainbow, P S

2014-10-01

The fouling barnacle Amphibalanus amphitrite is a cosmopolitan biomonitor of trace metal bioavailabilities, with an international comparative data set of body metal concentrations. Bioavailabilities of As, Cd, Cr, Cu, Fe, Mn, Pb, V and Zn to A. amphitrite were investigated at 19 sites along the Iranian coast of the understudied Persian Gulf. Commercial and fishing ports showed extremely high Cu bioavailabilities, associated with high Zn bioavailabilities, possibly from antifouling paints and procedures. V availability was raised at one port, perhaps associated with fuel leakage. Cd bioavailabilities were raised at sites near the Strait of Hormuz, perhaps affected by adjacent upwelling off Oman. The As data allow a reinterpretation of the typical range of accumulated As concentrations in A. amphitrite. The Persian Gulf data add a new region to the A. amphitrite database, confirming its importance in assessing the ecotoxicologically significant trace metal contamination of coastal waters across the world. Copyright © 2014 Elsevier Ltd. All rights reserved.

Anthropogenic marine litter composition in coastal areas may be a predictor of potentially invasive rafting fauna

PubMed Central

Borrell Pichs, Yaisel J.; García-Vazquez, Eva

2018-01-01

Anthropogenic plastic pollution is a global problem. In the marine environment, one of its less studied effects is the transport of attached biota, which might lead to introductions of non-native species in new areas or aid in habitat expansions of invasive species. The goal of the present work was to assess if the material composition of beached anthropogenic litter is indicative of the rafting fauna in a coastal area and could thus be used as a simple and cost-efficient tool for risk assessment in the future. Beached anthropogenic litter and attached biota along the 200 km coastline of Asturias, central Bay of Biscay, Spain, were analysed. The macrobiotic community attached to fouled litter items was identified using genetic barcoding combined with visual taxonomic analysis, and compared between hard plastics, foams, other plastics and non-plastic items. On the other hand, the material composition of beached litter was analysed in a standardized area on each beach. From these two datasets, the expected frequency of several rafting taxa was calculated for the coastal area and compared to the actually observed frequencies. The results showed that plastics were the most abundant type of beached litter. Litter accumulation was likely driven by coastal sources (industry, ports) and river/sewage inputs and transported by near-shore currents. Rafting vectors were almost exclusively made up of plastics and could mainly be attributed to fishing activity and leisure/ household. We identified a variety of rafting biota, including species of goose barnacles, acorn barnacles, bivalves, gastropods, polychaetes and bryozoan, and hydrozoan colonies attached to stranded litter. Several of these species were non-native and invasive, such as the giant Pacific oyster (Crassostrea gigas) and the Australian barnacle (Austrominius modestus). The composition of attached fauna varied strongly between litter items of different materials. Plastics, except for foam, had a much more diverse

Anthropogenic marine litter composition in coastal areas may be a predictor of potentially invasive rafting fauna.

PubMed

Rech, Sabine; Borrell Pichs, Yaisel J; García-Vazquez, Eva

2018-01-01

Anthropogenic plastic pollution is a global problem. In the marine environment, one of its less studied effects is the transport of attached biota, which might lead to introductions of non-native species in new areas or aid in habitat expansions of invasive species. The goal of the present work was to assess if the material composition of beached anthropogenic litter is indicative of the rafting fauna in a coastal area and could thus be used as a simple and cost-efficient tool for risk assessment in the future. Beached anthropogenic litter and attached biota along the 200 km coastline of Asturias, central Bay of Biscay, Spain, were analysed. The macrobiotic community attached to fouled litter items was identified using genetic barcoding combined with visual taxonomic analysis, and compared between hard plastics, foams, other plastics and non-plastic items. On the other hand, the material composition of beached litter was analysed in a standardized area on each beach. From these two datasets, the expected frequency of several rafting taxa was calculated for the coastal area and compared to the actually observed frequencies. The results showed that plastics were the most abundant type of beached litter. Litter accumulation was likely driven by coastal sources (industry, ports) and river/sewage inputs and transported by near-shore currents. Rafting vectors were almost exclusively made up of plastics and could mainly be attributed to fishing activity and leisure/ household. We identified a variety of rafting biota, including species of goose barnacles, acorn barnacles, bivalves, gastropods, polychaetes and bryozoan, and hydrozoan colonies attached to stranded litter. Several of these species were non-native and invasive, such as the giant Pacific oyster (Crassostrea gigas) and the Australian barnacle (Austrominius modestus). The composition of attached fauna varied strongly between litter items of different materials. Plastics, except for foam, had a much more diverse

Large-scale gene flow in the barnacle Jehlius cirratus and contrasts with other broadly-distributed taxa along the Chilean coast

PubMed Central

Guo, Baoying

2017-01-01

We evaluate the population genetic structure of the intertidal barnacle Jehlius cirratus across a broad portion of its geographic distribution using data from the mitochondrial cytochrome oxidase I (COI) gene region. Despite sampling diversity from over 3,000 km of the linear range of this species, there is only slight regional structure indicated, with overall Φ CT of 0.036 (p < 0.001) yet no support for isolation by distance. While these results suggest greater structure than previous studies of J. cirratus had indicated, the pattern of diversity is still far more subtle than in other similarly-distributed species with similar larval and life history traits. We compare these data and results with recent findings in four other intertidal species that have planktotrophic larvae. There are no clear patterns among these taxa that can be associated with intertidal depth or other known life history traits. PMID:28194316

Seedling Establishment of Coast Live Oak in Relation to Seed Caching by Jays

Treesearch

Joe R. McBride; Ed Norberg; Sheauchi Cheng; Ahmad Mossadegh

1991-01-01

The purpose of this study was to simulate the caching of acorns by jays and rodents to see if less costly procedures could be developed for the establishment of coast live oak (Quercus agrifolia). Four treatments [(1) random - single acorn cache, (2) regular - single acorn cache, (3) regular - 5 acorn cache, (4) regular - 10 acorn cache] were planted...

Infestation and morphological identification of the stalked epizoic barnacle Octolasmis on the blue crab Portunus pelagicus from the Red Sea

NASA Astrophysics Data System (ADS)

Afifi Khattab, Rafat

2017-09-01

The intensity of infestation of the epizoic stalked barnacle Octolasmis on the blue crab was calculated for a total of 180 individuals collected around Jeddah, the western Red Sea Saudi coast. More than 90% of the crabs were found bearing the Octolasmis at a prevalence rate of 92% and mean intensity of 18.5±18.6 (0-127 epibiont per host). The intensity of infestation increased with host size in the range 90-135 mm. Generally, females were more infested (69%) than the males (31%). Octolasmis angulata occurred mostly on the gills, and the lower side of the gill chambers was more infested (84%) than the upper side (16%) and the left side of gills was also more infested than the right side in both males and females. Further studies are still needed to examine the commensal relationship and its impact on the fishery market of the Red Sea blue crab populations.

Parallel Patterns of Host-Specific Morphology and Genetic Admixture in Sister Lineages of a Commensal Barnacle.

PubMed

Ewers-Saucedo, Christine; Chan, Benny K K; Zardus, John D; Wares, John P

2017-06-01

Symbiotic relationships are often species specific, allowing symbionts to adapt to their host environments. Host generalists, on the other hand, have to cope with diverse environments. One coping strategy is phenotypic plasticity, defined by the presence of host-specific phenotypes in the absence of genetic differentiation. Recent work indicates that such host-specific phenotypic plasticity is present in the West Pacific lineage of the commensal barnacle Chelonibia testudinaria (Linnaeus, 1758). We investigated genetic and morphological host-specific structure in the genetically distinct Atlantic sister lineage of C. testudinaria. We collected adult C. testudinaria from loggerhead sea turtles, horseshoe crabs, and blue crabs along the eastern U.S. coast between Delaware and Florida and in the Gulf of Mexico off Mississippi. We find that shell morphology, especially shell thickness, is host specific and comparable in similar host species between the Atlantic and West Pacific lineages. We did not detect significant genetic differentiation related to host species when analyzing data from 11 nuclear microsatellite loci and mitochondrial sequence data, which is comparable to findings for the Pacific lineage. The most parsimonious explanation for these parallel patterns between distinct lineages of C. testudinaria is that C. testudinaria maintained phenotypic plasticity since the lineages diverged 4-5 mya.

Effects of anions and cations on the resting membrane potential of internally perfused barnacle muscle fibres

PubMed Central

Lakshminarayanaiah, N.; Rojas, E.

1973-01-01

1. Single barnacle muscle fibres from Megabalanus psittacus (Darwin) were internally perfused with a number of K salt solutions (200 mM) which were made isotonic to the barnacle saline with sucrose. 2. 200 mM-K acetate solution, in general, was found to be more effective than other solutions of K salts in generating and maintaining stable resting membrane potential of -56·0 ± 0·7 mV (all potentials are referred to the external solutions as ground). The various K salts, on the basis of the magnitude of the resting potential they generated in the muscle fibres, followed the sequence, acetate > isethionate > aspartate > glutamate > fluoride > monohydrogen phosphate > succinate > citrate > sulphate > oxalate > iodobenzoate > ferrocyanide > chlorate > nitrate > chloride > thiocyanate > iodide > bromide > cyanide. 3. The resting potential in muscle fibres perfused with solutions of acetate, aspartate and glutamate increased linearly with the logarithm of the K concentration (slope = 30·4 mV for K acetate and 27·4 for K aspartate and glutamate) when the ionic strength of the solutions was progressively increased from 50 to 650 mM. On the other hand, similar increase of ionic strength beyond 200 mM of solutions of K isethionate, fluoride, monohydrogen phosphate, succinate and citrate depolarized the muscle fibres. 4. Perfusion of acetate solutions of other alkali metal ions gave low values for the resting potential and followed the sequence K > Na > Rb > Li > Cs. Also NH4 and Tris ions gave low values for the resting potential which underwent oscillations associated with the twitching of the fibre and occasionally became positive in value (action potential). 5. Addition of tetraethyl ammonium chloride (TEA-Cl), 20-100 mM, to K acetate solutions (200 mM) depolarized the fibre membrane and the consequent reduction of resting potential varied linearly with the logarithm of TEA concentration. 6. Replacement of chloride ion by acetate or isethionate in the external

Host-Specific Phenotypic Plasticity of the Turtle Barnacle Chelonibia testudinaria: A Widespread Generalist Rather than a Specialist

PubMed Central

Chu, Ka Hou; Cheng, I-Jiunn; Chan, Benny K. K.

2013-01-01

Turtle barnacles are common epibionts on marine organisms. Chelonibia testudinaria is specific on marine turtles whereas C. patula is a host generalist, but rarely found on turtles. It has been questioned why C. patula, being abundant on a variety of live substrata, is almost absent from turtles. We evaluated the genetic (mitochondrial COI, 16S and 12S rRNA, and amplified fragment length polymorphism (AFLP)) and morphological differentiation of C. testudinaia and C. patula from different hosts, to determine the mode of adaptation exhibited by Chelonibia species on different hosts. The two taxa demonstrate clear differences in shell morphology and length of 4–6th cirri, but very similar in arthropodal characters. Moreover, we detected no genetic differentiation in mitochondrial DNA and AFLP analyses. Outlier detection infers insignificant selection across loci investigated. Based on combined morphological and molecular evidence, we proposed that C. testudinaria and C. patula are conspecific, and the two morphs with contrasting shell morphologies and cirral length found on different host are predominantly shaped by developmental plasticity in response to environmental setting on different hosts. Chelonibia testudinaria is, thus, a successful general epibiotic fouler and the phenotypic responses postulated can increase the fitness of the animals when they attach on hosts with contrasting life-styles. PMID:23469208

The Effects of Various Ions on Resting and Spike Potentials of Barnacle Muscle Fibers

PubMed Central

Hagiwara, Susumu; Chichibu, Shiko; Naka, Ken-ichi

1964-01-01

Effects of monovalent cations and some anions on the electrical properties of the barnacle muscle fiber membrane were studied when the intra- or extracellular concentrations of those ions were altered by longitudinal intra-cellular injection. The resting potential of the normal fiber decreases linearly with increase of logarithm of [K+]out and the decrement for a tenfold increase in [K+]out is 58 mv when the product, [K+]out ·[Cl-]out, is kept constant. It also decreases with decreasing [K+]in but is always less than expected theoretically. The deviation becomes larger as [K+]in increases and the resting potential finally starts to decrease with increasing [K+]in for [K+]in > 250 mM. When the internal K+ concentration is decreased the overshoot of the spike potential increases and the time course of the spike potential becomes more prolonged. In substituting for the internal K+, Na+ and sucrose affect the resting and spike potentials similarly. Some organic cations (guanidine, choline, tris, and TMA) behave like sucrose while some other organic cations (TEA, TPA, and TBA) have a specific effect and prolong the spike potential if they are applied intracellularly or extracellularly. In all cases the active membrane potential increases linearly with the logarithm of [Ca++]out/[K+]in and the increment is about 29 mv for tenfold increase in this ratio. The fiber membrane is permeable to Cl- and other smaller anions (Br- and I-) but not to acetate- and larger anions (citrate-, sulfate-, and methanesulfonate-). PMID:14212147

Sensitivity to injected cholera toxin of the sodium efflux in single barnacle muscle fibers.

PubMed

Bittar, E E; Nwoga, J

1984-01-01

A study has been made of the effect of microinjected cholera toxin (CT) on the efflux in single barnacle muscle fibers. Characteristically, injected CT causes sustained stimulation of the ouabain-insensitive Na efflux but only after a lag phase. An effect is seen with as little as a 10(-7) M-solution of CT. Sustained stimulation after a lag phase is also seen following injection of subunit A fragment. Enrichment of fibers with NAD+ fails to enhance the response to CT. Prior injection of GTP or its non-hydrolyzeable analogue, Gpp(NH)p, markedly reduces the response to CT, whilst prior injection of CT reduces the response to guanine nucleotides. Evidence is also brought forward that omission of external Ca2+ reversibly reduces the response to CT and that pre- or postinjection of EGTA markedly reduces the response to CT. In addition, fibers preinjected with CT show increased aequorin light emission. Whereas verapamil and Cd2+ are ineffective, both Mg2+ and trace metals, e.g. Fe and Zn, reverse the response to CT following injection. Prior injection of protein kinase inhibitor reduces the response to CT. As for calmodulin inhibitors, e.g. chlorpromazine, imipramine and mepacrine, they are effective in reducing the response to CT but not calmodulin antibody (IgG). Collectively, the above results are compatible with the view that sustained stimulation of the ouabain-insensitive Na efflux by injected CT is due to persistent activation of adenylate cyclase by the toxin and that a fall in myoplasmic pCa facilitates or augments this activation mechanism.

The effect of climate on the phenology, acorn crop and radial increment of pedunculate oak (Quercus robur) in the middle Volga region, Tatarstan, Russia.

PubMed

Askeyev, O V; Tischin, D; Sparks, T H; Askeyev, I V

2005-03-01

Our data, collected in the extreme east of Europe, show that a significant biological effect of climate change has been experienced even in territories where temperature increase has been the lowest. This study documents the climatic response of pedunculate oak (Quercus robur) growing near its north-eastern limits in Europe. It demonstrates the potential of oak trees in old-growth forest to act as proxy climate indicators. Many factors may influence the temporal stability of the growth-climate, acorn crop-climate and first leafing-climate relationships. Climate data, climatic fluctuations, reproduction, genetics and tree-age may relate to this instability. Our results stress that an increase in climate variability or climatic warming resulting from warmer winters or summers could affect the oak population in eastern Europe in a similar way to that in western Europe. These findings, from remnants of oak forest in the middle Volga region of Russia, allow a further understanding of how species could be affected by future climates.

A novel bioassay using the barnacle Amphibalanus amphitrite to evaluate chronic effects of aluminium, gallium and molybdenum in tropical marine receiving environments.

PubMed

van Dam, Joost W; Trenfield, Melanie A; Harries, Simon J; Streten, Claire; Harford, Andrew J; Parry, David; van Dam, Rick A

2016-11-15

A need exists for appropriate tools to evaluate risk and monitor potential effects of contaminants in tropical marine environments, as currently impact assessments are conducted by non-representative approaches. Here, a novel bioassay is presented that allows for the estimation of the chronic toxicity of contaminants in receiving tropical marine environments. The bioassay is conducted using planktonic larvae of the barnacle Amphibalanus amphitrite and is targeted at generating environmentally relevant, chronic toxicity data for water quality guideline derivation or compliance testing. The developmental endpoint demonstrated a consistently high control performance, validated through the use of copper as a reference toxicant. In addition, the biological effects of aluminium, gallium and molybdenum were assessed. The endpoint expressed high sensitivity to copper and moderate sensitivity to aluminium, whereas gallium and molybdenum exhibited no discernible effects, even at high concentrations, providing valuable information on the toxicity of these elements in tropical marine waters. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

Patterns of Geographic Synchrony in Growth and Reproduction of Oaks Within California and Beyond

Treesearch

Walter D. Koenig; Johannes M.H. Knops

1997-01-01

We measured patterns of spatial synchrony in growth and reproduction by oaks using direct acorn surveys, published data on acorn production, and tree-ring chronologies. The two data sets involving acorn production both indicate that acorn crops are detectably synchronous over areas of at least 500 to 1,000 km not only within individual species but among species that...

Annual temperature variation as a time machine to understand the effects of long-term climate change on a poleward range shift.

PubMed

Crickenberger, Sam; Wethey, David S

2018-05-10

Range shifts due to annual variation in temperature are more tractable than range shifts linked to decadal to century long temperature changes due to climate change, providing natural experiments to determine the mechanisms responsible for driving long-term distributional shifts. In this study we couple physiologically grounded mechanistic models with biogeographic surveys in 2 years with high levels of annual temperature variation to disentangle the drivers of a historical range shift driven by climate change. The distribution of the barnacle Semibalanus balanoides has shifted 350 km poleward in the past half century along the east coast of the United States. Recruits were present throughout the historical range following the 2015 reproductive season, when temperatures were similar to those in the past century, and absent following the 2016 reproductive season when temperatures were warmer than they have been since 1870, the earliest date for temperature records. Our dispersal dependent mechanistic models of reproductive success were highly accurate and predicted patterns of reproduction success documented in field surveys throughout the historical range in 2015 and 2016. Our mechanistic models of reproductive success not only predicted recruitment dynamics near the range edge but also predicted interior range fragmentation in a number of years between 1870 and 2016. All recruits monitored within the historical range following the 2015 colonization died before 2016 suggesting juvenile survival was likely the primary driver of the historical range retraction. However, if 2016 is indicative of future temperatures mechanisms of range limitation will shift and reproductive failure will lead to further range retraction in the future. Mechanistic models are necessary for accurately predicting the effects of climate change on ranges of species. © 2018 John Wiley & Sons Ltd.

An Anatomical Description of a Miniaturized Acorn Worm (Hemichordata, Enteropneusta) with Asexual Reproduction by Paratomy

PubMed Central

Worsaae, Katrine; Sterrer, Wolfgang; Kaul-Strehlow, Sabrina; Hay-Schmidt, Anders; Giribet, Gonzalo

2012-01-01

The interstitial environment of marine sandy bottoms is a nutrient-rich, sheltered habitat whilst at the same time also often a turbulent, space-limited, and ecologically challenging environment dominated by meiofauna. The interstitial fauna is one of the most diverse on earth and accommodates miniaturized representatives from many macrofaunal groups as well as several exclusively meiofaunal phyla. The colonization process of this environment, with the restrictions imposed by limited space and low Reynolds numbers, has selected for great morphological and behavioral changes as well as new life history strategies. Here we describe a new enteropneust species inhabiting the interstices among sand grains in shallow tropical waters of the West Atlantic. With a maximum body length of 0.6 mm, it is the first microscopic adult enteropneust known, a group otherwise ranging from 2 cm to 250 cm in adult size. Asexual reproduction by paratomy has been observed in this new species, a reproductive mode not previously reported among enteropneusts. Morphologically, Meioglossus psammophilus gen. et sp. nov. shows closest resemblance to an early juvenile stage of the acorn worm family Harrimaniidae, a result congruent with its phylogenetic placement based on molecular data. Its position, clearly nested within the larger macrofaunal hemichordates, suggests that this represents an extreme case of miniaturization. The evolutionary pathway to this simple or juvenile appearance, as chiefly demonstrated by its small size, dense ciliation, and single pair of gill pores, may be explained by progenesis. The finding of M. psammophilus gen. et sp. nov. underscores the notion that meiofauna may constitute a rich source of undiscovered metazoan diversity, possibly disguised as juveniles of other species. PMID:23144898

pH regulation in barnacle muscle fibers: dependence on extracellular sodium and bicarbonate.

PubMed

Boron, W F; McCormick, W C; Roos, A

1981-01-01

Intracellular pH (pHi) regulation was studied in barnacle muscle fibers with pH-sensitive microelectrodes. The cells were acid loaded, and the subsequent recovery of pHi was monitored. The rate of recovery was reduced by one-third when external Na+ ([Na+]o) was replaced by Li+, but recovery was completely abolished when Na+ was replaced by choline or N-methyl-D-glucamine. In other experiments, varying amounts of Na+ were replaced by choline, and the acid extrusion rate, derived from the recovery rate of pHi, was calculated at a single value of pHi, 6.80. The dependence of the acid extrusion rate on [Na+]o could be described by Michaelis-Menten kinetics; at pHo (extracellular) = 8.0 and [HCO3-]o (extracellular) = 10 mM, the apparent Km and Vmax were 59 mM and 1.3 mmol x l(-1) x min-1. When [HCO3-]o was reduced to 2.5 mM at the same pHo, Km did not change significantly, but Vmax was substantially reduced. On the other hand, when pHo was reduced to 7.4 at constant [HCO3-]o, Vmax changed only slightly, but Km increased substantially. In similar experiments, we examined the dependence of the acid extrusion rate on [HCO3-]o. At pHo = 8.0 and [Na+]o = 440 mM, the apparent Km and Vmax were 4.1 mM and 2.1 mmol x 1-1 x min-1. When pHo was reduced to 7.4, Vmax was not altered, but Km substantially increased. The kinetic data are discussed in terms of the role of pHo, [Na+]o, and [HCO3-]o in the pHi-regulating system.

Phylogeography of a Marine Insular Endemic in the Atlantic Macaronesia: The Azorean Barnacle, Megabalanus azoricus (Pilsbry, 1916)

PubMed Central

González, José A.; Almeida, Corrine; Lopes, Evandro; Araújo, Ricardo; Carreira, Gilberto P.

2015-01-01

The Azorean barnacle, Megabalanus azoricus (Pilsbry, 1916), is a Macaronesian endemic whose obscure taxonomy and the unknown relationships among forms inhabiting isolated Northern Atlantic oceanic islands is investigated by means of molecular analysis herein. Mitochondrial data from the 16S rRNA and COX1 genes support its current species status, tropical ancestry, and the taxonomic homogeneity throughout its distribution range. In contrast, at the intraspecific level and based on control region sequences, we detected an overall low level of genetic diversity and three divergent lineages. The haplogroups α and γ were sampled in the Azores, Madeira, Canary, and Cabo Verde archipelagos; whereas haplogroup β was absent from Cabo Verde. Consequently, population analysis suggested a differentiation of the Cabo Verde population with respect to the genetically homogenous northern archipelagos generated by current oceanographic barriers. Furthermore, haplogroup α, β, and γ demographic expansions occurred during the interglacial periods MIS5 (130 Kya - thousands years ago -), MIS3 (60 Kya), and MIS7 (240 Kya), respectively. The evolutionary origin of these lineages is related to its survival in the stable southern refugia and its demographic expansion dynamics are associated with the glacial-interglacial cycles. This phylogeographic pattern suggests the occurrence of genetic discontinuity informative to the delimitation of an informally defined biogeographic entity, Macaronesia, and its generation by processes that delineate genetic diversity of marine taxa in this area. PMID:25919141

Fate and Contribution of Internal Wave-Forced Barnacle Settlers to Community Structure in Northern Baja California, a Year after Settlement

NASA Astrophysics Data System (ADS)

Lievana, A.; Ladah, L. B.; Lavin, M. F.; Filonov, A. E.; Tapia, F. J.; Leichter, J.; Valencia Gasti, J. A.

2016-02-01

Physical transport processes, such as nonlinear internal waves, operating within the coastal ocean of Baja California, Mexico, are diverse, variable and operate on a variety of temporal and spatial scales. Understanding the influence of nonlinear internal waves, in part responsible for the exchange of water properties between coastal and offshore environments, on the structure of intertidal communities is important for the generation of working ecological models. The relationship between the supply of ecological subsidies associated with physical transport processes that operate on relatively short spatial and temporal scales, such as the internal tide, and intertidal community structure must be understood as processes that operate on distinct spatial and temporal scales may be prone to react uniquely as the climate changes. We designed an experiment to quantify recruitment and adult survivorship of Chthamalus sp. whose settlement was associated with internal wave activity in the nearby ocean and found that the number of settlers was a robust predictor of the number of adults observed, indicating that post-settlement processes such as competition and predation are not likely to significantly affect the structure of the intertidal barnacle community resulting from internal-wave forced settlement.

Pollen-limited reproduction in blue oak: Implications for wind pollination in fragmented populations

USGS Publications Warehouse

Knapp, E.E.; Goedde, M.A.; Rice, K.J.

2001-01-01

Human activities are fragmenting forests and woodlands worldwide, but the impact of reduced tree population densities on pollen transfer in wind-pollinated trees is poorly understood. In a 4-year study, we evaluated relationships among stand density, pollen availability, and seed production in a thinned and fragmented population of blue oak (Quercus douglasii). Geographic coordinates were established and flowering interval determined for 100 contiguous trees. The number of neighboring trees within 60 m that released pollen during each tree's flowering period was calculated and relationships with acorn production explored using multiple regression. We evaluated the effects of female flower production, average temperature, and relative humidity during the pollination period, and number of pollen-producing neighbors on individual trees' acorn production. All factors except temperature were significant in at least one of the years of our study, but the combination of factors influencing acorn production varied among years. In 1996, a year of large acorn crop size, acorn production was significantly positively associated with number of neighboring pollen producers and density of female flowers. In 1997, 1998, and 1999, many trees produced few or no acorns, and significant associations between number of pollen-producing neighbors and acorn production were only apparent among moderately to highly reproductive trees. Acorn production by these reproductive trees in 1997 was significantly positively associated with number of neighboring pollen producers and significantly negatively associated with average relative humidity during the pollination period. In 1998, no analysis was possible, because too few trees produced a moderate to large acorn crop. Only density of female flowers was significantly associated with acorn production of moderately to highly reproductive trees in 1999. The effect of spatial scale was also investigated by conducting analyses with pollen producers

Seed Production in Southern Appalachian Oak Stands

Treesearch

Donald E. Beck; David F. Olson

1968-01-01

Acorn production in mixed oak stands of different densities varied considerably among stands, years, and species. Density had no effect on total acorn production. Although numerous acorns were initiated each year, the majority either failed to develop fully or were damaged by insects and animals.

78 FR 35110 - Airworthiness Directives; Piper Aircraft, Inc. Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-12

... and Acorn Welding stated that we should mention exhaust parts fail at flanges due to exhaust assembly... Douglas Deering, Joe Miller, Acorn Welding, Allen H. Bower, and AMBO Ltd. stated we should specify which v...-Overhauls Douglas Deering, Terry Mangione, and Acorn Welding stated that we should limit exhaust system life...

vasa-related genes and their expression in stem cells of colonial parasitic rhizocephalan barnacle Polyascus polygenea (Arthropoda: Crustacea: Cirripedia: Rhizocephala).

PubMed

Shukalyuk, Andrey I; Golovnina, Kseniya A; Baiborodin, Sergei I; Gunbin, Konstantin V; Blinov, Alexander G; Isaeva, Valeria V

2007-02-01

vasa (vas)-related genes are members of the DEAD-box protein family and are expressed in the germ cells of many Metazoa. We cloned vasa-related genes (PpVLG, CpVLG) and other DEAD-box family related genes (PpDRH1, PpDRH2, CpDRH, AtDRHr) from the colonial parasitic rhizocephalan barnacle Polyascus polygenea, the non-colonial Clistosaccus paguri (Crustacea: Cirripedia: Rhizocephala), and the parasitic isopodan Athelgis takanoshimensis (Crustacea: Isopoda). The colonial Polyascus polygenea, a parasite of the coastal crabs Hemigrapsus sanguineus and Hemigrapsus longitarsis was used as a model object for further detailed investigations. Phylogenetic analysis suggested that PpVLG and CpVLG are closely related to vasa-like genes of other Arthropoda. The rest of the studied genes form their own separate branch on the phylogenetic tree and have a common ancestry with the p68 and PL10 subfamilies. We suppose this group may be a new subfamily of the DEAD-box RNA helicases that is specific for parasitic Crustacea. We found PpVLG and PpDRH1 expression products in stem cells from stolons and buds of internae, during asexual reproduction of colonial P. polygenea, and in germ cells from sexually reproducing externae, including male spermatogenic cells and female oogenic cells.

Invasion and morphological variation of the non-indigenous barnacle Chthamalus challengeri (Hoek, 1883) in Yangshan Port and its surrounding areas

NASA Astrophysics Data System (ADS)

Liu, Yan; Xue, Junzeng; Lin, Junda; Wu, Huixian

2015-06-01

Invasive species generally possess unique characteristics that allow them to survive the invasion process in order to establish and spread in new habitats. Successful invaders must resist both physical and physiological stresses associated with the changing environment. A common littoral barnacle, Chthamalus challengeri Hoek, 1883 (Crustacea, Cirripedia), which is native to Japan, South Korea and northern China, has become established in the high-littoral zone adjacent to Yangshan Port, Shanghai, China. A comparison of the morphology of Chthamlus species from Zhoushan archipelago with previous description indicates the occurrence of C. challengeri. The new immigrant becomes a dominant species in certain high-intertidal habitats of the adjacent area to of Yangshan Port. C. challengeri was found in part of sampling sites in Zhoushan in 2010; however, it dispersed to all the eleven sampling sites in 2012. Densities of C.challengeri had increased over 10 times in the last 2 years, with the highest mean value reaching 39533 ± 6243 ind. m-2 in the new habitat. The specific ratios of both operculum area ( Sa) to base area ( SA) and average height of parietal plates ( H) to length of base ( L) revealed that C. challengeri displays morphological changes to resist stronger currents in the new habitats for invasion.

Germination Characteristics of Engelmann Oak and Coast Live Oak from the Santa Rosa Plateau, Riverside County, California

Treesearch

Gerald E. Snow

1991-01-01

Over 2,000 acorns of Quercus agrifolia (coast live oak) and over 500 acorns of Q. engelmannii (Engelmann oak) were collected in the Jim Knight pasture area of the Santa Rosa Plateau. These were used to test for temperature and moisture conditions on germination of viable acorns in the laboratory under controlled environmental...

Phylogeography of hydrothermal vent stalked barnacles: a new species fills a gap in the Indian Ocean 'dispersal corridor' hypothesis.

PubMed

Watanabe, Hiromi Kayama; Chen, Chong; Marie, Daniel P; Takai, Ken; Fujikura, Katsunori; Chan, Benny K K

2018-04-01

Phylogeography of animals provides clues to processes governing their evolution and diversification. The Indian Ocean has been hypothesized as a 'dispersal corridor' connecting hydrothermal vent fauna of Atlantic and Pacific oceans. Stalked barnacles of the family Eolepadidae are common associates of deep-sea vents in Southern, Pacific and Indian oceans, and the family is an ideal group for testing this hypothesis. Here, we describe Neolepas marisindica sp. nov. from the Indian Ocean, distinguished from N. zevinae and N. rapanuii by having a tridentoid mandible in which the second tooth lacks small elongated teeth. Morphological variations suggest that environmental differences result in phenotypic plasticity in the capitulum and scales on the peduncle in eolepadids. We suggest that diagnostic characters in Eolepadidae should be based mainly on more reliable arthropodal characters and DNA barcoding, while the plate arrangement should be used carefully with their intraspecific variation in mind. We show morphologically that Neolepas specimens collected from the South West Indian Ridge, the South East Indian Ridge and the Central Indian Ridge belong to the new species. Molecular phylogeny and fossil evidence indicated that Neolepas migrated from the southern Pacific to the Indian Ocean through the Southern Ocean, providing key evidence against the 'dispersal corridor' hypothesis. Exploration of the South East Indian Ridge is urgently required to understand vent biogeography in the Indian Ocean.

Research and management in a young northern red oak seedling seed orchard

Treesearch

S.E. Schlarbaum; J.L. McConnell; L.R. Barber; R.A. Cox; J.F. Grant; Paul P. Kormanik; T. La Farge; P.L. Lambdin; S.W. Oak; C.K. Proffitt; J.R. Rhea; T. Tibbs

1994-01-01

A northern red oak progeny test was thinned at age 15 to produce a seedling seed orchard. Studies were initiated to determine relationships between acorn production and seed source. Acorn production was observed in 1984-1986 and 1989-1992.Family differences were observed in reproductive maturity. Large differences in size of acorns from the same tree were observed...

Life history and notes on the biology of Stelidota octomaculata (Coleoptera:Nitidulidae)

Treesearch

Jimmy R. Galford; Roger N. Williams; Ann Daugherty; Ann Daugherty

1991-01-01

The life history of Stelidota octomaculata (Say) was studied in Ohio and Pennsylvania. This insect damages acorns and affects the establishment of oak seedlings. Acorns deployed in wire cages and pitfall traps plus a sampling of naturally occurring acorns were used to monitor insect activity. AdLllts overwinter in forest litter and begin feeding on undamaged...

Arboreal seed removal and insect damage in three California oaks

Treesearch

Walter D. Koenig; Johannes M. H. Knops; William J. Carmen

2002-01-01

We investigated arboreal removal and insect damage to acorns in an undisturbed oak woodland in central coastal California. Arboreal seed removal was determined for four to eight individual Quercus lobata trees over a period of 14 years by comparing visual estimates of the acorn crop with the number of acorns caught in seed traps. Insect damage was...

Notes on the biology and hosts of Stelidota ferruginea (Coleoptera:Nitidulidae)

Treesearch

Jimmy R. Galford; Roger N. Williams; Mary Beacom; Mary Beacom

1991-01-01

The nitidulid Stelidota ferruginea Reitter was reared from damaged acorns of laurel oak, Quercus laurifolia Michx., and live oak, Q. virginiana Mill., collected in Sarasota County, Florida. This sap beetle has been reared in the laboratory solely on northern red oak, Q. rubra, acorns for over 3 years (27 + generations) and can breed in viable or nonviable acorns. In...

Studies Show Steps to More Success Planting Oak Forests

Treesearch

Robert L. Johnson

1986-01-01

As Ann Nestelroad observes in a preceding article, acorns sown 6 inches deep can germinate and produce seedlings. I believe, however, that the best oak establishment comes from acorns sown 1 to 2 inches deep in open areas. Deep sowing does not substantially reduce acorn depredation by rodents, but two ongoing studies at Stoneville, Mississippi, indicate that sowing in...

Bored to Death: Community-Wide Effect of Predation on a Foundation Species in a Low-Disturbance Arctic Subtidal System.

PubMed

Yakovis, Eugeniy; Artemieva, Anna

2015-01-01

The strength of top-down control by consumers is predicted to decrease with latitude, but most data confirming this assumption come from latitudes <60°, while empirical studies of predation in sub-arctic and arctic marine habitats are few. A barnacle Balanus crenatus is a native foundation species in the shallow subtidal of the White Sea (65° N), hosting a diverse (250+ species) assemblage of macrobenthic organisms. On mixed sediments live barnacles share primary substrates (shells and gravel) with numerous empty barnacle tests, 7% of which had drill holes of an unidentified origin. We manipulated the densities of (i) adult muricid whelks Boreotrophon clathratus (of previously unknown feeding habits), to check if they prey on barnacles, (ii) other predators to reveal their effect on juvenile Boreotrophon, and (iii) empty tests to assess the community-wide effect of predation on barnacles. The abundance of drilled empty tests in the field correlated with that of Boreotrophon. A year-long caging experiment clearly confirmed predation, showing the highest barnacle mortality and proportion of drilled tests in whelk enclosures, and the lowest--in predator exclosure treatments. Boreotrophon preferred the barnacles attached to conspecifics to those from primary substrates. Because of its scarcity Boreotrophon had a minor direct effect on barnacle abundance in the field. Yet, initially defaunated empty tests and live barnacles developed markedly different macrobenthic assemblages, suggesting a strong indirect effect of the predation. Juvenile Boreotrophon were 5-6 times less abundant in open and partial cages than in exclosures and enclosures, which indicates that the recruitment and, consequently, the abundance of Boreotrophon and its predation on Balanus are top-down controlled by apex predators. In contrast, in tropical and temperate intertidal the predation on barnacles is stronger and primarily limited by environmental stress and prey availability.

Contemporary California Indians, oaks and Sudden Oak Death (Phytophthora ramorum)

Treesearch

Beverly R. Ortiz

2008-01-01

This paper begins with a survey of contemporary California Indian utilization of acorns for food, including an examination of: (1) familial, community and cultural contexts in which acorn is shared and eaten; (2) new and old acorn processing techniques in use today and the foods that result; (3) the symbolic context of the foods in terms of ecological and social...

Phylogeography of hydrothermal vent stalked barnacles: a new species fills a gap in the Indian Ocean ‘dispersal corridor’ hypothesis

PubMed Central

Marie, Daniel P.; Takai, Ken; Fujikura, Katsunori

2018-01-01

Phylogeography of animals provides clues to processes governing their evolution and diversification. The Indian Ocean has been hypothesized as a ‘dispersal corridor’ connecting hydrothermal vent fauna of Atlantic and Pacific oceans. Stalked barnacles of the family Eolepadidae are common associates of deep-sea vents in Southern, Pacific and Indian oceans, and the family is an ideal group for testing this hypothesis. Here, we describe Neolepas marisindica sp. nov. from the Indian Ocean, distinguished from N. zevinae and N. rapanuii by having a tridentoid mandible in which the second tooth lacks small elongated teeth. Morphological variations suggest that environmental differences result in phenotypic plasticity in the capitulum and scales on the peduncle in eolepadids. We suggest that diagnostic characters in Eolepadidae should be based mainly on more reliable arthropodal characters and DNA barcoding, while the plate arrangement should be used carefully with their intraspecific variation in mind. We show morphologically that Neolepas specimens collected from the South West Indian Ridge, the South East Indian Ridge and the Central Indian Ridge belong to the new species. Molecular phylogeny and fossil evidence indicated that Neolepas migrated from the southern Pacific to the Indian Ocean through the Southern Ocean, providing key evidence against the ‘dispersal corridor’ hypothesis. Exploration of the South East Indian Ridge is urgently required to understand vent biogeography in the Indian Ocean. PMID:29765686

Study of variability in antioxidant composition and fatty acids profile of Longissimus dorsi and Serratus ventralis muscles from Iberian pigs reared in two different Montanera seasons.

PubMed

Tejerina, D; García-Torres, S; de Vaca, M Cabeza; Vázquez, F M; Cava, R

2012-02-01

This investigation was designed to evaluate the effects of variations in antioxidant and fatty acids composition of acorns and grass from two Montanera (free-range system and feeding based on acorns and grass) seasons (2006/07 and 2007/08) on the antioxidant composition and fatty acids profile of m. Longissimus dorsi (LD) and m. Serratus ventralis (SV) from Iberian pigs reared under these Montanera seasons. Acorn and grass composition was affected by Montanera season and consequently, LD and SV muscles showed different contents of α-tocopherol, total phenols, hydrophilic and lipophilic antioxidant activity and fatty acid profile, according with the composition of acorns and grass ingested. Results suggest a lack of uniformity in meat quality between different seasons. This could be due to the variable nature of extensive pig production as reflected in the variability in the composition of the diet (acorns and grass). Copyright © 2011 Elsevier Ltd. All rights reserved.

Influence of elevated temperature, pCO2, and nutrients on larva-biofilm interaction: Elucidation with acorn barnacle, Balanus amphitrite Darwin (Cirripedia: Thoracica)

NASA Astrophysics Data System (ADS)

Baragi, Lalita V.; Anil, Arga Chandrashekar

2017-02-01

Selection of optimal habitat by larvae of sessile organism is influenced by cues offered by the biofilm. Ocean warming and acidification are likely to enforce changes in the biofilm community and inturn influence the settlement process. Hence, we evaluated the influence of biofilm (multispecies and unialgal) and diet-mediated changes on the settlement of Balanus amphitrite cyprids (presettlement non-feeding larval stage) under different combinations of temperature (28, 30, 32 and 34 °C), pCO2 (400, 750 and 1500 μatm) and nutrient (unenriched and f/2 enriched). Nutrient enrichment enhanced the diatom and bacterial abundance at ambient temperature (30 °C) and pCO2 (400 μatm), which inturn increased larval settlement. Elevated pCO2 (750 and 1500 μatm) had no direct effect but a variable cascading effect on the settlement via biofilm-mediated changes was observed, depending on the type of biofilm. In contrast, elevated temperature (32 and 34 °C), either individually or in combination with elevated pCO2 had direct negative effect on settlement. However, biofilm-mediated changes compensated this negative effect. The larval settlement was also influenced by changes in the larval diet. Under elevated temperature and pCO2, cyprids raised with a feed (Chaetoceros calcitrans) from ambient temperature and pCO2 were of poor quality (lower RNA:DNA ratio, lower protein synthetic capacity) and yielded lower settlement. However, cyprids raised with a feed from elevated temperature and pCO2 were of better quality (higher RNA:DNA ratio, higher protein synthetic capacity) and yielded higher settlement. Overall, the observations from the present study provide insights into the significance of biotic interactions on the coastal biofouling communities under future climatic scenario and emphasise the need for future experiments on these aspects.

The interaction of intracellular Mg2+ and pH on Cl- fluxes associated with intracellular pH regulation in barnacle muscle fibers

PubMed Central

1988-01-01

The intracellular dialysis technique was used to measure unidirectional Cl- fluxes and net acid extrusion by single muscle fibers from the giant barnacle. Decreasing pHi below normal levels of 7.35 stimulated both Cl- efflux and influx. These increases of Cl- fluxes were blocked by disulfonic acid stilbene derivatives such as SITS and DIDS. The SITS- sensitive Cl- efflux was sharply dependent upon pHi, increasing approximately 20-fold as pHi was decreased from 7.35 to 6.7. Under conditions of normal intracellular Mg2+ concentration, the apparent pKa for the activation of Cl- efflux was 7.0. We found that raising [Mg2+]i, but not [Mg2+]o, had a pronounced inhibitory effect on both SITS-sensitive unidirectional Cl- fluxes as well as on SITS-sensitive net acid extrusion. Increasing [Mg2+]i shifted the apparent pKa of Cl- efflux to a more acid value without affecting the maximal flux that could be attained. This relation between pHi and [Mg2+]i on SITS- sensitive Cl- efflux is consistent with a competition between H ions and Mg ions. We conclude that the SITS-inhibitable Cl- fluxes are mediated by the pHi-regulatory transport mechanism and that changes of intracellular Mg2+ levels can modify the activity of the pHi regulator/anion transporter. PMID:3392519

Characterization of the phosphatic mineral of the barnacle Ibla cumingi at atomic level by solid-state nuclear magnetic resonance: comparison with other phosphatic biominerals

PubMed Central

Reid, David G.; Mason, Matthew J.; Chan, Benny K. K.; Duer, Melinda J.

2012-01-01

Ibliform barnacles are among the few invertebrate animals harnessing calcium phosphate to construct hard tissue. The 31P solid-state NMR (SSNMR) signal from the shell plates of Ibla cumingi (Iblidae) is broader than that of bone, and shifted by ca 1 ppm to low frequency. 1H–31P heteronuclear correlation (HETCOR) experiments show a continuum of different phosphorus/phosphate atomic environments, close to hydrogen populations with resonance frequencies between ca 10 and 20 ppm. Associated 1H and 31P chemical shifts argue the coexistence of weakly (high 31P frequency, low 1H frequency) to more strongly (lower 31P frequency, higher 1H frequency) hydrogen-bonded hydrogen phosphate-like molecular/ionic species. There is no resolved signal from discrete OH− ions. 13C SSNMR shows chitin, protein and other organic biomolecules but, unlike bone, there are no significant atomic scale organic matrix–mineral contacts. The poorly ordered hydrogen phosphate-like iblid mineral is strikingly different, structurally and compositionally, from both vertebrate bone mineral and the more crystalline fluoroapatite of the linguliform brachiopods. It probably represents a previously poorly characterized calcium phosphate biomineral, the evolution of which may have reflected either the chemical conditions of ancestral seas or the mechanical advantages of phosphatic biomineralization over a calcium carbonate equivalent. PMID:22298816

Larval settlement rate: a leading determinant of structure in an ecological community of the marine intertidal zone

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gaines, S.; Roughgarden, J.

Field studies demonstrate that the population structure of the barnacle Balanus glandula differs between locations of high and low larval settlement rate. These observations, together with results from a model for the demography of an open, space-limited population, suggest that the settlement rate may be a more important determinant of rocky intertidal community structure than is presently realized. At the low-settlement location mortality of barnacles is independent of the area occupied by barnacles. At the high-settlement location mortality is cover-dependent due to increased predation by starfish on areas of high barnacle cover. In both locations the cover-independent component of mortalitymore » does not vary with age during the first 60 weeks. Generalizations that the highest species diversity in a rocky intertidal community is found at locations of intermediate disturbance, and that competition causes zonation between species of the barnacle genera Balanus and Chthamalus, seem to apply only to locations with high-settlement rates.« less

Evaluating the microscopic fecal technique for estimating hard mast in turkey diets

Treesearch

Mark A. Rumble; Stanley H. Anderson

1993-01-01

Wild and domestic dark turkeys (Meleagris gallopavo) were fed experimental diets containing acorn (Quercus gambelli), ponderosa pine (Pinus ponderosa) seed, grasses, forbs, and arthropods. In fecal estimates of diet composition, acorn and ponderosa pine seed were underestimated and grass was overestimated....

Large bowel fermentation of maize or sorghum-acorn diets fed as a different source of carbohydrates to Landrace and Iberian pigs.

PubMed

Morales, J; Pérez, J F; Martín-Orúe, S M; Fondevila, M; Gasa, J

2002-11-01

Twenty-four finishing pigs (twelve Iberian and twelve Landrace) were used in a growing and slaughtering experiment. Animals were fed two diets differing in their ingredients, maize (diet C) or sorghum-acorn (diet A). At an average weight of 107.0 kg pigs were slaughtered and hindgut digesta sampled to study the effect of breed and diet on large bowel fermentation. Flows of digesta to the hindgut compartment were estimated based on an indigestible flow marker (Cr2O3) and were higher in Iberian than in Landrace pigs (P<0.001), and higher in animals fed diet A than diet C (P=0.07). The higher flows in Iberian pigs were mainly associated with a higher voluntary feed intake (3.50 v. 2.70 kg/d, P<0.01) and lower ileal digestibility of NSP (-12.8 v. 47.8, P<0.01). Differences between diets were mainly associated with a lower ileal digestibility of starch from diet A (89.2 v. 96.9 %, P=0.06), although no differences in the resistant starch content were observed in vitro. Fermentation of different carbohydrates through the large bowel showed that NSP-glucose had lower digestibility in Iberian than in Landrace pigs (62.5 v. 94.2 %, P<0.001), but no differences were observed in starch, or other NSP-fibre fractions (arabinose, xylose and galactose). The type and amount of carbohydrates reaching the large bowel were related to the diet but also to breed, and promoted differences in the fermentative activity associated with different volatile fatty acid patterns and changes in microbial enzymic activity.

Long-term exposure to acidification disrupts reproduction in a marine invertebrate

PubMed Central

Hattich, Giannina S. I.; Heinrichs, Mara E.; Pansch, Andreas; Zagrodzka, Zuzanna; Havenhand, Jonathan N.

2018-01-01

Climate change research is advancing to more complex and more comprehensive studies that include long-term experiments, multiple life-history stages, multi-population, and multi-trait approaches. We used a population of the barnacle Balanus improvisus known to be sensitive to short-term acidification to determine its potential for long-term acclimation to acidification. We reared laboratory-bred individuals (as singles or pairs), and field-collected assemblages of barnacles, at pH 8.1 and 7.5 (≈ 400 and 1600 μatm pCO2 respectively) for up to 16 months. Acidification caused strong mortality and reduced growth rates. Acidification suppressed respiration rates and induced a higher feeding activity of barnacles after 6 months, but this suppression of respiration rate was absent after 15 months. Laboratory-bred barnacles developed mature gonads only when they were held in pairs, but nonetheless failed to produce fertilized embryos. Field-collected barnacles reared in the laboratory for 8 months at the same pH’s developed mature gonads, but only those in pH 8.1 produced viable embryos and larvae. Because survivors of long-term acidification were not capable of reproducing, this demonstrates that B. improvisus can only partially acclimate to long-term acidification. This represents a clear and significant bottleneck in the ontogeny of this barnacle population that may limit its potential to persist in a future ocean. PMID:29408893

Nutritional value of winter foods for whooping cranes

USGS Publications Warehouse

Nelson, J.T.; Slack, R.D.; Gee, G.F.

1996-01-01

We measured metabolizable energy and digestibility of Whooping Crane (Grus americana) winter foods (blue crab [Callinectes sapidus]), common Rangia clam (Rangia cuneata), wolfberry fruit (Lycium carolinianurn [wolfberry]), and live oak acorn (Ouercus virginiana [acorn])] with feeding trials to captive-reared Whooping Cranes. Apparent metabolizable energy coefficients (expressed as %) were for crab (34.1), Rangia clam (75.0), wolfberry (44.8), and acorn (43.2). Digestion coefficients for protein were lower for plant foods (48.9 and 53.4) than for animal foods (69.4 and 75.2). Digestion coefficients for total lipid differed among foods: highest and lowest lipid digestibility was for acorn (87.2) and wolfberry (60.0), respectively. We also determined total energy and percent protein and lipid of the four foods and stout razor clam (Tagelus plebeius); gross energy was 2-5x higher for acorn and wolfberry on a dry-weight basis than for blue crab and stout razor clam. Crude protein was 2-3x higher for blue crab than for wolfberry and stout razor clam. Wolfberry ranked the highest of five foods for metabolic energy and total lipid nutrient availability per kg of food ingested, and blue crab ranked highest for crude protein availability.

Identification of a transformer homolog in the acorn worm, Saccoglossus kowalevskii, and analysis of its activity in insect cells.

PubMed

Suzuki, Masataka G; Tochigi, Mayuko; Sakaguchi, Honami; Aoki, Fugaku; Miyamoto, Norio

2015-06-01

The transformer (tra) gene is an intermediate component of the sex determination hierarchy in many insect species. The homolog of tra is also found in two branchiopod crustacean species but is not known outside arthropods. We have isolated a tra homolog in the acorn worm, Saccoglossus kowalevskii, which is a hemichordate belonging to the deuterostome superphylum. The full-length complementary DNA (cDNA) of the S. kowalevskii tra homolog (Sktra) has a 3786-bp open reading frame that encodes a 1261-amino acid sequence including a TRA-CAM domain and an arginine/serine (RS)-rich domain, both of which are characteristic of TRA orthologs. Reverse transcription PCR (RT-PCR) analyses demonstrated that Sktra showed no differences in expression patterns between testes and ovaries, but its expression level was approximately 7.5-fold higher in the testes than in the ovaries. TRA, together with the protein product of the transformer-2 (tra-2) gene, assembles on doublesex (dsx) pre-messenger RNA (mRNA) via the cis-regulatory element, enhancing female-specific splicing of dsx in Drosophila. To understand functional conservation of the SkTRA protein as a dsx-splicing activator, we investigated whether SkTRA is capable of inducing female-specific splicing of the Drosophila dsx. Ectopic expression of Sktra cDNA in insect cultured cells did not induce the female-specific splicing of dsx. On the other hand, forced expression of Sktra-2 (a tra-2 homolog of S. kowalevskii) was able to induce the female-specific dsx splicing. These results demonstrate that the function as a dsx-splicing activator is not conserved in SkTRA even though SkTRA-2 is capable of functionally replacing the Drosophila TRA-2. We have also found a tra homolog in an echinoderm genome. This study provides the first evidence that that tra is conserved not only in arthropods but also in basal species of deuterostoms.

Masting characteristics of white oak: implications for management

Treesearch

Marcus A. Lashley; John M. McCord; Cathryn H. Greenberg; Craig A. Harper

2009-01-01

Acorn production is variable from year to year and among species. Weather, insect damage, and genetics are primary causes for variation. Silvicultural techniques have been recommended to improve acorn production; however, those recommendations primarily address variation among red oaks (Quercus rubra). Variability among individual white oaks (Quercus alba) has not been...

Differential recolonization of Atlantic intertidal habitats after disturbance reveals potential bottom-up community regulation.

PubMed

Petzold, Willy; Scrosati, Ricardo A

2014-01-01

In the spring of 2014, abundant sea ice that drifted out of the Gulf of St. Lawrence caused extensive disturbance in rocky intertidal habitats on the northern Atlantic coast of mainland Nova Scotia, Canada. To monitor recovery of intertidal communities, we surveyed two wave-exposed locations in the early summer of 2014. Barnacle recruitment and the abundance of predatory dogwhelks were low at one location (Tor Bay Provincial Park) but more than 20 times higher at the other location (Whitehead). Satellite data indicated that the abundance of coastal phytoplankton (the main food source for barnacle larvae) was consistently higher at Whitehead just before the barnacle recruitment season, when barnacle larvae were in the water column. These observations suggest bottom-up forcing of intertidal communities. The underlying mechanisms and their intensity along the NW Atlantic coast could be investigated through studies done at local and regional scales.

Update on oak seed quality research: Hardwood recalcitrant seeds

Treesearch

Kristina F. Connor

2004-01-01

In 2 experiments, acorns of cherrybark oak (Quercus pagoda Raf.) and water oak (Q. nigra L.) were stored at 2 temperatures and 2 moisture contents for 3 years, and acorns of white oak (Q. alba L.) and cherrybark oak were desiccated over a span of up to 11 days and examined for physiological and biochemical...

Bioerosion of gastropod shells: with emphasis on effects of coralline algal cover and shell microstructure

NASA Astrophysics Data System (ADS)

Smyth, Miriam J.

1989-12-01

Organisms boring into fifty nine species of gastropod shells on reefs around Guam were the bryozoan Penetrantia clionoides; the acrothoracian barnacles Cryptophialus coronorphorus, Cryptophialus zulloi and Lithoglyptis mitis; the foraminifer Cymbaloporella tabellaeformis, the polydorid Polydora sp. and seven species of clionid sponge. Evidence that crustose coralline algae interfere with settlement of larvae of acrothoracian barnacles, clionid sponges, and boring polychaetes came from two sources: (1) low intensity of boring in limpet shells, a potentially penetrable substrate that remains largely free of borings by virtue of becoming fully covered with coralline algae at a young age and (2) the extremely low levels of boring in the algal ridge, a massive area of carbonate almost entirely covered by a layer of living crustose corallines. There was a strong negative correlation between microstructural hardness and infestation by acrothoracian barnacles and no correlation in the case of the other borers. It is suggested that this points to a mechanical rather than a chemical method of boring by the barnacles. The periostracum, a layer of organic material reputedly a natural inhibitor of boring organisms, was bored by acrothoracican barnacles and by the bryozoan. The intensity of acrothoracican borings is shown to have no correlation with the length of the gastropod shell.

Epicormic branching of California black oak: effect of stand and tree characteristics

Treesearch

Philip M. McDonald; Martin W. Ritchie

1994-01-01

Young California black oak (Quercus kelloggii Newb.) stands usually require thinning to increase production of acorns and wood products, but epicormic branches, which yield no acorns and constitute a serious lumber degrade. often result. A crown thinning in 60-year-old hardwood stands on a south exposure at the Challenge Experimental Forest in thenorthern Sierra Nevada...

Flush Development Dynamics in First-Year Nursery-Grown Seedlings of Eight Oak Species

Treesearch

Shi-Jean S. Sung; Paul P. Kormanik; Stanley J. Zarnoch

2004-01-01

Two experiments were conducted to follow flush development dynamics exhibited by various oak species. In experiment I, southern red oak acorns were sown in mid-March 2001 at Whitehall Nursery (Athens, GA). In experiment II, acorns of black oak, cherrybark oak, Nuttall oak, Shumard oak, southern red oak, swamp chestnut oak, white oak, and willow oak were sown in...

Oak Dispersal Syndromes: Do Red and White Oaks Exhibit Different Dispersal Srategies?

Treesearch

Michael Steele; Peter Smallwood; William B. Terzaghi; John E. Carlson; Thomas conteras; Amy McEuen

2004-01-01

We provide an overview of the ecological and evolutionary interactions between oaks and several of their dispersal agents, and review a series of studies that demonstrate how various acorn characteristics affect feeding and caching decisions of these animals, which in turn may influence oak dispersal and establishment. We demonstrate that acorns of red oak species show...

Intertidal biological indicators of coseismic subsidence during the Mw 7.8 Haida Gwaii, Canada, earthquake

USGS Publications Warehouse

Haeussler, Peter J.; Witter, Robert C.; Wang, Kelin

2015-01-01

The 28 October 2012 Mw 7.8 Haida Gwaii earthquake was a megathrust earthquake along the very obliquely convergent Queen Charlotte margin of British Columbia, Canada. Coseismic deformation is not well constrained by geodesy, with only six Global Positioning System (GPS) sites and two tide gauge stations within 250 km of the rupture area. To better constrain vertical coseismic deformation, we measured the upper growth limits of two sessile intertidal organisms, which are controlled by physical conditions, relative to sea level at 25 sites 5 months after the earthquake. We measured the positions of rockweed (Fucus distichus, 617 observations) and the common acorn barnacle (Balanus balanoides, 686 observations). The study focused on the western side of the islands where rupture models indicated that the greatest amount of vertical displacement, but we also investigated sites well away from the inferred rupture area to provide a control on the upper limit of the organisms unaffected by vertical displacement. We also made 322 measurements of sea level to relate the growth limits to a tidal datum using the TPXO7.2 tidal model, rather than ellipsoid heights determined by GPS. Three methods of examining the data all indicate 0.4–0.6 m subsidence along the western coast of Moresby Island as a result of the 28 October 2012 Haida Gwaii earthquake. Our data are, within the errors, consistent with data from two campaign GPS sites along the west coast of Haida Gwaii and with rupture models that indicate megathrust rupture offshore, but not beneath, the islands.

Modified Activated Carbon Prepared from Acorn Shells as a New Solid-Phase Extraction Sorbent for the Preconcentration and Determination of Trace Amounts of Nickel in Food Samples Prior to Flame Atomic Absorption Spectrometry.

PubMed

Ebrahimi, Bahram

2017-03-01

A new solid-phase extraction (SPE) sorbent was introduced based on acidic-modified (AM) activated carbon (AC) prepared from acorn shells of native oak trees in Kurdistan. Hydrochloric acid (15%, w/w) and nitric acid (32.5%, w/w) were used to condition and modify AC. The IR spectra of AC and AM-AC showed that AM lead to the formation of increasing numbers of acidic functional groups on AM-AC. AM-AC was used in the SPE method for the extraction and preconcentration of Ni+2 prior to flame atomic absorption spectrometric determination at ng/mL levels in model and real food samples. Effective parameters of the SPE procedure, such as the pH of the solutions, sorbent dosage, extraction time, sample volume, type of eluent, and matrix ions, were considered and optimized. An enrichment factor of 140 was obtained. The calibration curve was linear with an R2 of 0.997 in the concentration range of 1-220 ng/mL. The RSD was 5.67% (for n = 7), the LOD was 0.352 ng/mL, and relative recoveries in vegetable samples ranged from 96.7 to 103.7%.

Short-term losses and long-term gains: The non-native species Austrominius modestus in Lough Hyne Marine Nature Reserve

NASA Astrophysics Data System (ADS)

Gallagher, M. C.; Culloty, S. C.; Davenport, J.; Harman, L.; Jessopp, M. J.; Kerrigan, C.; Murray, C.; O'Riordan, R. M.; McAllen, R.

2017-05-01

The non-native barnacle species Austrominius modestus was first recorded in Ireland, close to Lough Hyne marine nature reserve in 1957. This species was not recorded inside the Lough until 1980, but by 2001 was the dominant intertidal barnacle within the reserve. It has been suggested that increases in the abundance of this species at other locations in Europe may be linked to increasing sea surface temperatures, and that A. modestus is an "ecological sleeper". Despite an overall trend for increasing sea surface temperatures, this long term warming is punctuated by extreme events such as severely cold winters. A. modestus is warm water adapted, and has been recorded to decrease in abundance following cold winters. The winters of 2009/2010 and 2010/2011 were amongst the coldest recorded in Ireland in past decades. In the present study, higher levels of mortality were recorded for A. modestus than native barnacle species in Lough Hyne following these cold winters. Additionally, this species was recorded at lower abundances at the majority of sites surveyed in Lough Hyne in 2011 compared with 2009. Despite this, A. modestus remains the dominant barnacle species in the Lough and monitoring the recruitment of intertidal barnacles within Lough Hyne during 2014-2015 revealed that A. modestus was the most abundant recruit at study sites, both in removal plots and in the pre-existing community. The year-round breeding of A. modestus in addition to the closed nature of the Lough promotes A. modestus within the reserve. Despite this, native barnacle species continue to persist in Lough Hyne, though generally at low abundances, with the exception of exposed locations such as the Rapids and Bullock Island where natives outnumber A. modestus. The future intertidal barnacle community within the Lough is likely to be dominated by A. modestus with Chthamalus montagui and C. stellatus being abundant at sites which are not suitable for A. modestus. While the consequences of this are

Regeneration of oaks by direct seeding

Treesearch

R. Johnson; R. Krinard

1985-01-01

Direct sowing of oak acorns has not always met with success. This paper summarizes recent research regarding direct sowing of oaks in research plots and commercial trials. Present findings indicate that seedlings can be established from properly stored acorns sown any month of the year by hand or machine. They should be sown at a 2-inch depth, although they can be sown...

Oak Regeneration by Direct Seeding

Treesearch

Robert L. Johnson; Roger M. Krinard

1985-01-01

Direct sowing of oak acorns has not always met with success. This paper summarizes recent research regarding direct sowing of oaks in research plots and commercial trials. Present findings indicate that seedlings can be established from properly stored acorns sown any month of the year by hand or machine . They should be sown at a two-inch depth , although they can be...

The use of nutritional guidance within chiropractic patient management: a survey of 333 chiropractors from the ACORN practice-based research network.

PubMed

Lee, Mi Kyung; Amorin-Woods, Lyndon; Cascioli, Vincenzo; Adams, Jon

2018-01-01

Food consumption and nutritional status affect an individual's health throughout their life-course and an unhealthy diet is a major risk factor for the current global burden of chronic disease. The promotion of health and good nutrition through healthy eating requires the active involvement of all health professionals including chiropractors. This paper reports findings from the first nationally representative examination of the use of nutritional guidance within chiropractic patient management in Australia. A sample of 1000 practising chiropractors was randomly selected from the Australian Chiropractic Research Network (ACORN) practice-based research network database for a cross-sectional study and 33% participated in the online survey in November 2016. The questionnaire, based on previous designs used in similar surveys and nutrition resources developed by the National Health and Medical Research Council, was pretested prior to the survey. Pearson's Chi square and bivariate logistic regression were undertaken to explore relationships with variables of interest. The demographic details of the respondents are similar to those of the chiropractic workforce registered in Australia. Most chiropractors provided nutritional advice as part of their patient care and around a quarter provided specific dietary advice to their patients, including the use of nutrition supplements. Nutrition-related conditions most commonly encountered by the chiropractors were musculoskeletal, usually inflammatory in origin. Common nutritional assessment methods used included questioning patients to assess their nutritional and health status and physical appearance. Most of the participants provided nutritional resources to their patients in their clinics. However, the Australian Dietary Guidelines and the accompanying Australian Guide to Healthy Eating were not well utilised by the respondents. Australian chiropractors often referred patients with nutrition issues to qualified dietitians and

Evaluation of Venturi Oxygen Stripping (trademark) as a Ballast Water Treatment to Prevent Aquatic Invasions and Ship Corrosion

DTIC Science & Technology

2003-01-01

that can withstand low oxygen levels (e.g., resistant cysts of dinoflagellates, Hallegraeff 1998). Marine bacteria, in particular, will have...Chesapeake Bay zooplankton (copepods, barnacle larvae, polychaete larvae, cladocerans, crustacean nauplii, bivalve larvae, and nematodes ) in less than...zooplankton (copepods, barnacle larvae, polychaete larvae, cladocerans, crustacean nauplii, bivalve larvae, and nematodes ) in control and treated

Low levels of copper reduce the reproductive success of a mobile invertebrate predator.

PubMed

Lee, Ka-Man; Johnston, Emma L

2007-09-01

Marine organisms that occur in urbanised bays can be exposed to low-level chronic pollution that results in sublethal changes to behavior or reproduction. The effects of low levels of copper on the reproductive success of a mobile invertebrate were assessed. Free living flatworms are common predators of bivalves and barnacles. Flatworms (Stylochus pygmaeus) were exposed to low levels of copper ranging from 0 to 25 microg L(-1) in the presence and absence of their barnacle prey (Balanus variegatus). Flatworms laid fewer egg batches when exposed to copper and the hatching success of the eggs was also reduced. Exposure to 25 microg L(-1) copper for 10 d reduced the reproductive success of flatworms by up to 80%. Results were consistent regardless of the presence or absence of prey (barnacles). Barnacles were only moderately affected by copper but exhibited major avoidance behavior (feeding inhibition) in the presence of flatworm predators. This is the first ecotoxicological study on marine flatworms. Experiments are required to quantify the effects of flatworm predator populations on sessile invertebrate community structure in the field.

Oak-black bear relationships in southeastern uplands

USGS Publications Warehouse

Clark, Joseph D.; Spetich, Martin A.

2004-01-01

Bears (Ursus americanus) primarily occur in upland habitats in the Southeast because uplands were the last to be developed for agriculture and were more likely to become publicly owned. National parks and forests created in the early to mid-1900s served as sources to supply surrounding uplands with bears. Bears could not survive in southeastern uplands without oak mast. Bear reproductive and mortality rates in the region have been shown to be directly linked with acorn production. Masting is thought to be an adaptation by oaks to satiate predators during good acorn years, thus ensuring that the remainder will germinate. Acorn predator populations, however, cannot respond numerically to increased acorn production because the masting is episodic and synchronous. Consequently, bears have developed physiological, behavioral, and ecological adaptations to cope with such food shortages. Despite such adaptations, upland hardwood forests in the Southeast are of lower quality than they once were. The loss of the American chestnut (Castanea dentata), higrading, and soil degradation have markedly decreased the carrying capacity for bears and other wildlife. Other changes such as recent forest management practices, forest fragmentation, invasion by the gypsy moth (Lymantria dispar), and oak decline threaten to further degrade the capability of southeastern uplands to support bears.

Correlated Biogeographic Variation of Magnesium across Trophic Levels in a Terrestrial Food Chain

PubMed Central

Sun, Xiao; Kay, Adam D.; Kang, Hongzhang; Small, Gaston E.; Liu, Guofang; Zhou, Xuan; Yin, Shan; Liu, Chunjiang

2013-01-01

Using samples from eastern China (c. 25 – 41° N and 99 – 123° E) and from a common garden experiment, we investigate how Mg concentration varies with climate across multiple trophic levels. In soils, plant tissue (Oriental oak leaves and acorns), and a specialist acorn predator (the weevil Curculio davidi), Mg concentration increased significantly with different slopes from south to north, and generally decreased with both mean annual temperature (MAT) and precipitation (MAP). In addition, soil, leaf, acorn and weevil Mg showed different strengths of association and sensitivity with climatic factors, suggesting that distinct mechanisms may drive patterns of Mg variation at different trophic levels. Our findings provide a first step toward determining whether anticipated changes in temperature and precipitation due to climate change will have important consequences for the bioavailability and distribution of Mg in food chain. PMID:24223807

Smal-Scale Spatial Differences in Supply-Side Ecology of Barnacle Larvae Involves a Complex Suite of Factors (Including Surface Tide, Internal Tides And Surface Winds) in Baja California

NASA Astrophysics Data System (ADS)

Valencia, A.; Ladah, L. B.

2016-02-01

The objective of this study was to quantify and compare the daily settlement rate of barnacle larvae of Chthamalus spp. at small spatial scales ( 1 km) at three sites with unique geomorphology. Simultaneously, water-column temperature, currents, and coastal winds were measured to detect potential physical transport mechanisms responsible for supply of planktonic larvae to the coast. Autocorrelation artifacts in the environmental and settlement time series were removed with the Autoregressive Integrated Moving Average (ARIMA) and their residuals were used to perform a Principal Component Analysis (PCA). This analysis was carried out to determine the independent modes of variability in the environmental forcing mechanisms that may explain the settlement patterns. We found synchronous settlement pulses occurring throughout the study. Settlement at the wave exposed site was only associated to the wind-forcing mode and not to internal waves, which had not been detected previously and was surprising, considering the strong semidiurnal internal tide at this site. Settlement at both the reef-bounded site and the inside-bay site associated to vertical isotherm displacements, thereby suggesting the importance of internal waves for supply-side ecology at these more southern sites. Our results suggest that a complex suite of factors may interact to result in larval supply at the same site, and that larval supply at nearby sites may be forced by different factors due to differences in geomorphology and/or bathymetry, explaining spatial heterogeneity often detected in larval supply and settlement.

Depth and coral cover drive the distribution of a coral macroborer across two reef systems.

PubMed

Maher, Rebecca L; Johnston, Michelle A; Brandt, Marilyn E; Smith, Tyler B; Correa, Adrienne M S

2018-01-01

Bioerosion, the removal of calcium carbonate from coral frameworks by living organisms, influences a variety of reef features, from their topographic complexity to the net balance of carbonate budgets. Little is known, however, about how macroborers, which bore into reef substrates leaving traces greater than 0.1 mm diameter, are distributed across coral reefs, particularly reef systems with high (>50%) stony coral cover or at mesophotic depths (≥30 m). Here, we present an accurate and efficient method for quantifying macroborer densities from stony coral hosts via image analysis, using the bioeroding barnacle, Lithotrya dorsalis, and its host coral, Orbicella franksi, as a case study. We found that in 2014, L. dorsalis densities varied consistently with depth and host percent cover in two Atlantic reef systems: the Flower Garden Banks (FGB, northwest Gulf of Mexico) and the U.S. Virgin Islands (USVI). Although average barnacle density was nearly 4.5 times greater overall in the FGB than in the USVI, barnacle density decreased with depth in both reef regions. Barnacle density also scaled negatively with increasing coral cover in the study areas, suggesting that barnacle populations are not strictly space-limited in their distribution and settlement opportunities. Our findings suggest that depth and host coral cover, and potentially, local factors may strongly influence the abundance of macroborers, and thus the rate of CaCO3 loss, in a given reef system. Our image analysis method for quantifying macroborers can be standardized across historical and modern reef records to better understand how borers impact host growth and reef health.

Drag Enhancement of Microbial Slime Films on Rotating Discs.

DTIC Science & Technology

1981-03-27

barnacle and algal growth , had also occurred (7). Laboratory culture eliminated these contaminants. The bacteria were grown in artificial seawater (Instant...attachment and growth under flow conditions , using an aquarium power filter pump (12). Films grown in this manner were sufficiently adherent to plastic...the large and easily visible organisms, such as barnacles, bryozoa, and tubeworms do not prevent attachment and growth of micro-organisms, which may

Chemical Component and Proteomic Study of the Amphibalanus (= Balanus) amphitrite Shell

PubMed Central

Zhang, Gen; He, Li-sheng; Wong, Yue-Him; Xu, Ying; Zhang, Yu; Qian, Pei-yuan

2015-01-01

As typical biofoulers, barnacles possess hard shells and cause serious biofouling problems. In this study, we analyzed the protein component of the barnacle Amphibalanus (= Balanus) amphitrite shell using gel-based proteomics. The results revealed 52 proteins in the A. Amphitrite shell. Among them, 40 proteins were categorized into 11 functional groups based on KOG database, and the remaining 12 proteins were unknown. Besides the known proteins in barnacle shell (SIPC, carbonic anhydrase and acidic acid matrix protein), we also identified chorion peroxidase, C-type lectin-like domains, serine proteases and proteinase inhibitor proteins in the A. Amphitrite shell. The sequences of these proteins were characterized and their potential functions were discussed. Histology and DAPI staining revealed living cells in the shell, which might secrete the shell proteins identified in this study. PMID:26222041

Defund ACORN Act

THOMAS, 111th Congress

Rep. Boehner, John A. [R-OH-8

2009-09-15

House - 10/23/2009 Referred to the Subcommittee on Government Management, Organization, and Procurement. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

Archeological Testing at at the Fairchild Site (LA 45732) Otero County, New Mexico.

DTIC Science & Technology

1985-05-11

rid the acorns of tannin and to render them palatable, they were heat-treated. The most common method was to remove the acorn hull, grind the...valve shell, or carved of wood or antler ( Heizer and Elsas- ser 1980:92-93]. Heizer and Elsasser calculated that a family of five, working 8 hours a...three years), enough for several years’ storage ( Heizer and Elsasser 1980:95-96). Mesquite beans, one of the most important dietary items for the desert

Comparison of microelectrode, DMO, and methylamine methods for measuring intracellular pH.

PubMed

Boron, W F; Roos, A

1976-09-01

The intracellular pH (pHi) of giant barnacle muscle fibers was measured with glass microelectrodes and also calculated from the distribution of 5,5-dimethyl-2,4-oxazolidinedione (DMO) and methylamine (MA). Simultaneously applying any two of these methods to muscle fibers of the same barnacle, we found the pH measured with an intracellular electrode (pH-Elec) to be about 0.06 higher than the DMO-derived pH (pH-DMO), and pH-DMO to be about 0.10 higher than the MA-derived pH (p-ma). in studies on the pHi of squid giant axons, we found that pH-Elec (7.35) and pH-DMO (7.36) were not significantly different. In the barnacle experiments, DMO required about 30 min to reach a steady-state distribution, while MA required more than 5 h. The deviations of pH-DMO and pH-MA from pH-Elec for the barnacle can be explained by a) an error in the assumed intracellular pKa' of DMO or MA, b) membrane permeability to the ionic form of DMO or MA, or c) intracellular compartmentalization. Included is a detailed study of the apparent dissociation constant of DMO as affected by temperature, and ionic strength and composition.

Habitat traits and food availability determine the response of marine invertebrates to ocean acidification.

PubMed

Pansch, Christian; Schaub, Iris; Havenhand, Jonathan; Wahl, Martin

2014-03-01

Energy availability and local adaptation are major components in mediating the effects of ocean acidification (OA) on marine species. In a long-term study, we investigated the effects of food availability and elevated pCO2 (ca. 400, 1000 and 3000 μatm) on growth of newly settled Amphibalanus (Balanus) improvisus to reproduction, and on their offspring. We also compared two different populations, which were presumed to differ in their sensitivity to pCO2 due to differing habitat conditions: Kiel Fjord, Germany (Western Baltic Sea) with naturally strong pCO2 fluctuations, and the Tjärnö Archipelago, Sweden (Skagerrak) with far lower fluctuations. Over 20 weeks, survival, growth, reproduction and shell strength of Kiel barnacles were all unaffected by elevated pCO2 , regardless of food availability. Moulting frequency and shell corrosion increased with increasing pCO2 in adults. Larval development and juvenile growth of the F1 generation were tolerant to increased pCO2 , irrespective of parental treatment. In contrast, elevated pCO2 had a strong negative impact on survival of Tjärnö barnacles. Specimens from this population were able to withstand moderate levels of elevated pCO2 over 5 weeks when food was plentiful but showed reduced growth under food limitation. Severe levels of elevated pCO2 negatively impacted growth of Tjärnö barnacles in both food treatments. We demonstrate a conspicuously higher tolerance to elevated pCO2 in Kiel barnacles than in Tjärnö barnacles. This tolerance was carried over from adults to their offspring. Our findings indicate that populations from fluctuating pCO2 environments are more tolerant to elevated pCO2 than populations from more stable pCO2 habitats. We furthermore provide evidence that energy availability can mediate the ability of barnacles to withstand moderate CO2 stress. Considering the high tolerance of Kiel specimens and the possibility to adapt over many generations, near future OA alone does not seem to

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dean, T.A.; Bellis, V.J.

Epifaunal species were collected at 1-, 3-, and 12-month intervals from the Pamlico River estuary. Three epifaunal communities were recognized by characteristic species assemblages. The permanently mesohaline mouth was dominated by Garveia cerulea (hydroid), Balanus improvisus (barnacle), Victorella pavida and Membranipora tenuis (bryozoans), Diadumene leucolena (anemone), Ercolania vanellus (nudibranch), Corophium lacustre (amphipod), and Polydora websteri and Nereis succinea (polychaetes). Upriver, in oligohaline portions, dominants were Cordylophora caspia (hydroid), Balanus subalbidus and Balanus improvisus (barnacles), Victorella pavida (bryozoan), and Polydora websteri (polychaete). Between these extremes, the intermediate zone was dominated by representatives of the extremes: Balanus improvisus, Cordylophora caspia, Victorella pavida,more » Corophium lacustre (amphipod), and Polydora websteri. Demarcation of communities corresponded to salinity patterns. Within each community wide seasonal variation was demonstrated by species composition, relative abundance, and dry weight. Epifauna were most abundant in warm months (May to October) and relatively sparse the rest of the year. Seasonal expression of community structure was attributed to periodicity in larval release and settlement and was thus initiated and directed by the annual pattern of water temperature, dissolved oxygen, salinity, and interspecific competition. The sequence of epifaunal dominants began with barnacles and hydroids in the spring, a bryozoan in summer, and a smaller set of barnacles with associated tubeworms in fall. Community succession began with bacteria and protozoans followed by sessile epifauna and finally motile epifaunal associates.« less

Soil and Rock Yogi

NASA Image and Video Library

1997-07-06

Several possible targets of study for rover Sojourner's Alpha Proton X-Ray Spectrometer (APXS) instrument are seen in this image, taken by the Imager for Mars Pathfinder (IMP) on Sol 2. The smaller rock at left has been dubbed "Barnacle Bill," while the larger rock at right, approximately 3-4 meters from the lander, is now nicknamed "Yogi." Barnacle Bill is scheduled to be the first object of study for the APXS. Portions of a petal and deflated airbag are also visible at lower right. http://photojournal.jpl.nasa.gov/catalog/PIA00629

Rover Tracks

NASA Image and Video Library

1997-07-07

Tracks made by the Sojourner rover are visible in this image, taken by one of the cameras aboard Sojourner on Sol 3. The tracks represent the rover maneuvering towards the rock dubbed "Barnacle Bill." The rover, having exited the lander via the rear ramp, first traveled towards the right portion of the image, and then moved forward towards the left where Barnacle Bill sits. The fact that the rover was making defined tracks indicates that the soil is made up of particles on a micron scale. http://photojournal.jpl.nasa.gov/catalog/PIA00633

On a Possible Evolutionary Link of the Stomochord of Hemichordates to Pharyngeal Organs of Chordates

PubMed Central

Satoh, Noriyuki; Tagawa, Kunifumi; Lowe, Christopher J.; Yu, Jr-Kai; Kawashima, Takeshi; Takahashi, Hiroki; Ogasawara, Michio; Kirschner, Marc; Hisata, Kanako; Su, Yi-Hsien; Gerhart, John

2017-01-01

Summary As a group closely related to chordates, hemichordate acorn worms are in a key phylogenic position for addressing hypotheses of chordate origins. The stomochord of acorn worms is an anterior outgrowth of the pharynx endoderm into the proboscis. In 1886 Bateson proposed homology of this organ to the chordate notochord, crowning this animal group “hemichordates.” Although this proposal has been debated for over a century, the question still remains unresolved. Here we review recent progress related to this question. First, the developmental mode of the stomochord completely differs from that of the notochord. Second, comparison of expression profiles of genes including Brachyury, a key regulator of notochord formation in chordates, does not support the stomochord/notochord homology. Third, FoxE that is expressed in the stomochord-forming region in acorn worm juveniles is expressed in the club-shaped gland and in the endostyle of amphioxus, in the endostyle of ascidians, and in the thyroid gland of vertebrates. Based on these findings, together with the anterior endodermal location of the stomochord, we propose that the stomochord has evolutionary relatedness to chordate organs deriving from the anterior pharynx rather than to the notochord. PMID:25303744

On a possible evolutionary link of the stomochord of hemichordates to pharyngeal organs of chordates.

PubMed

Satoh, Noriyuki; Tagawa, Kunifumi; Lowe, Christopher J; Yu, Jr-Kai; Kawashima, Takeshi; Takahashi, Hiroki; Ogasawara, Michio; Kirschner, Marc; Hisata, Kanako; Su, Yi-Hsien; Gerhart, John

2014-12-01

As a group closely related to chordates, hemichordate acorn worms are in a key phylogenic position for addressing hypotheses of chordate origins. The stomochord of acorn worms is an anterior outgrowth of the pharynx endoderm into the proboscis. In 1886 Bateson proposed homology of this organ to the chordate notochord, crowning this animal group "hemichordates." Although this proposal has been debated for over a century, the question still remains unresolved. Here we review recent progress related to this question. First, the developmental mode of the stomochord completely differs from that of the notochord. Second, comparison of expression profiles of genes including Brachyury, a key regulator of notochord formation in chordates, does not support the stomochord/notochord homology. Third, FoxE that is expressed in the stomochord-forming region in acorn worm juveniles is expressed in the club-shaped gland and in the endostyle of amphioxus, in the endostyle of ascidians, and in the thyroid gland of vertebrates. Based on these findings, together with the anterior endodermal location of the stomochord, we propose that the stomochord has evolutionary relatedness to chordate organs deriving from the anterior pharynx rather than to the notochord. © 2014 Wiley Periodicals, Inc.

[Critical tidal level for Kandelia candel forestation in strong tidal range area].

PubMed

Qiu, Jian-biao; Huang, Li; Chen, Shao-bo; Chi, Wei; Ding, Wen-yong; Zhou, Chao-sheng; Zheng, Chun-fang; Wang, Wen-qing

2010-05-01

Taking Ximen island of Yueqing bay, the biggest tidal range area among the coasts of China, as study site, an investigation was made on the survival rate, growth characteristics, and attached barnacles of 1- and 3-year-old Kandelia candel seedlings at the elevations 1.96, 1.66, 1.35, and 1.03 m above the zero tidal level of Yellow Sea. Significant differences were observed in the survival rate and growth situation of the seedlings among the elevations. There were two barnacle species, Balanus albicostatus and Balanus amphitrite amphitrite, and B. albicostatus was the major species which attached K. candel most seriously at elevation 1.35 m. The critical tidal level for K. candel in the site was 1.66 m above the zero tidal level, i.e., at least 1.29 m higher than the local mean sea level, and the flooding time per tide cycle being less than 3.65 h. Barnacle, strong tide, and extreme weather event were the main reasons for the higher critical tidal level.

Influence of Pericarp, Cotyledon and Inhibitory Substances on Sharp Tooth Oak (Quercus aliena var. acuteserrata) Germination

PubMed Central

Liu, Yan; Liu, Guangquan; Li, Qingmei; Liu, Yong; Hou, Longyu; Li, GuoLei

2012-01-01

In order to explore the mechanism of delayed and uneven germination in sharp tooth oak (Quercus aliena var. acuteserrata) (STO), mechanical scarification techniques were used to study STO root and shoot germination and growth. The techniques used were: removing cup scar (RS), removing the pericarp (RP), and cutting off 1/2 (HC) and 2/3 (TC) cotyledons. Germination percentage and root and shoot length for Chinese cabbage (Beassica pekinensis) seeds (CCS) were also investigated for CCS cultivated in a Sanyo growth cabinet watered by distilled water and 80% methanol extracts from the acorn embryo, cotyledon and pericarp with concentrations of 1.0 g, 0.8 g, 0.6 g and 0.4 g dry acorn weight per ml methanol. The results showed that the majority of roots and shoots from acorns with RP and HC treatment emerged two weeks earlier, more simultaneously, and their total emergences were more than 46% and 28% higher, respectively. TC accelerated root and shoot emergence time and root length, but root and shoot germination rate and shoot height had no significant difference from the control. Positive consequences were not observed on all indices of RS treatment. The germination rates of CCS watered by 1.0 g·ml−1 methanol extracts from the embryo and cotyledon were significantly lower than those from the pericarp, and all concentrations resulted in decreased growth of root and shoot. Methanol extracts from pericarp significantly reduced root length of CCS, but presented little response in germination percentage and shoot length. The inhibitory effect was gradually increased with the increasing concentration of the methanol extract. We conclude that both the mechanical restriction of the pericarp and the presence of germination inhibitors in the embryo, cotyledon and pericarp are the causes for delayed and asynchronous germination of STO acorns. PMID:23133517

Ninth workshop on seedling physiology and growth problems in oak plantings (abstracts)

Treesearch

D.R. Weigel; J.W. Van Sambeek; C.H., eds. Michler

2005-01-01

Research results and ongoing research activities in field performance of oak plantings, seedling propagation, genetics, acorn germination, and natural regeneration of oaks are described in 26 abstracts.

Tenth workshop on seedling physiology and growth problems in oak plantings

Treesearch

Brian Roy Lockhart; Emile S. Gardiner; Daniel C. Dey

2008-01-01

Research results and ongoing research activities in field performance of oak plantings, seedling propagation, genetics, acorn germination, and natural regeneration of oaks are described in 15 abstracts.

Kinetic studies of amylase and biomass production by Calvatia gigantea

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kekos, D.; Macris, B.J.

1987-01-01

Production of alpha-amylase (alpha-4, glucan 4-glucanohydrolase, EC 3.2.1.1) by microorganisms has been practiced for many years in small and large scale operations and the literature on this enzyme is voluminous. Aspergillus niger and Aspergillus oryzae have been reported as the main fungal species used for commercial production of the enzyme. On the other hand, large volumes of low-cost agricultural products such as acorn (the perisperm-free dry seed contains approximately 60% starch) are wasted in many countries and provide a challenge to biotechnology to efficiently utilize these rich sources of starch for the production of high added value products like enzymes.more » C. gigantea is an edible puffball excreting high levels of alpha-amylase when cultivated on different sources of starch containing elevated quantities of toxic tannic compounds. This fungus has been employed for the production of microbial protein from wastes and acorns containing high levels of toxic tannic compounds. The same fungus was also reported to grow on both hydrolyzable and condensed tannins as sole carbon sources. The present work was undertaken to investigate certain kinetic characteristics of alpha-amylase and biomass production by C. gigantea grown on soluble and acorn starch in a lab fermenter. (Refs. 18).« less

Accumulation trends of petroleum hydrocarbons in commercial shellfish from the Galician coast (NW Spain) affected by the Prestige oil spill.

PubMed

Viñas, L; Franco, M A; Soriano, J A; González, J J; Ortiz, L; Bayona, J M; Albaigés, J

2009-04-01

Aliphatic and aromatic hydrocarbons were determined in three species of commercial shellfish, namely razor shells (Ensis arcuatus and Ensis siliqua), goose barnacle (Pollicipes cornucopia) and sea urchin (Paracentrotus lividus), living in different habitats and exhibiting different feeding behaviors. The samples were collected monthly, from January 2003 to October 2004, in three stations of the Galicia coast (NW Spain), following the Prestige oil spill, with the aim of assessing their response to the spill and, therefore, their suitability for monitoring purposes. The aliphatic fractions were mostly dominated by biogenic hydrocarbons, reflecting the diet composition of the organisms and their low metabolic capacity. The presence of oil was assessed by the determination of chemical markers. The analysis of the aromatic fractions revealed the occurrence of 3-6 ring parent and alkylated PAHs, consistent with a mixed petrogenic-pyrolytic origin, with the common feature of the predominance of chrysene in all samples collected after the spill. However, the distributions exhibited both temporal and interspecies variations. The PAH concentrations (Sigma13) increased significantly after the spill and decreased 6-7 months later close to background levels for the region. One year after the accident, the median values were: 58 microg/kg for razor shells, 26 microg/kg for barnacles, and 25 microg/kg for sea urchins. The temporal evolution of the PAH concentrations along the survey period was used to estimate loss rates for bioavailable PAHs in barnacles and sea urchins after the spill. Half-life values were in the order of 30 and 60 d, respectively. The results of the study demonstrate that barnacles can be suitable species for oil spill monitoring.

Eighth workshop on seedling physiology and growth problems in oak plantings (abstracts). 2001 September 9-12; Hiwassee, GA.

Treesearch

S. Sung; P.P. Kormanik; W.J. Ostrosina; J.G. Isebrands

2002-01-01

Research results and ongoing research activities in field performance of planted trees, seedling propagation, physiology, genetics, acorn germination, and natural regeneration for oaks are described in 21 abstracts.

Seventh workshop on seedling physiology and growth problems in oak plantings (abstracts); 1998 September 27-29; South Lake Tahoe, CA.

Treesearch

D.D. McCreary; J.G. Isebrands

1999-01-01

Research results and ongoing research activities in field performance of planted trees, seedling propagation, physiology, genetics, acorn germination, and natural regeneration for oaks are described in 17 abstracts.

Fifth workshop on seedling physiology and growth problems in oak plantings (abstracts).

Treesearch

Janette R. Thompson; Richard C. Schultz; J.W. Van Sambeek

1993-01-01

Research results and ongoing research activities in field performance of planted trees, seedling propagation, physiology, genetics, acorn germination, and natural regeneration for oaks are described in 30 abstracts.

Sixth workshop on seedling physiology and growth problems in oak plantings (abstracts); 1995 September 18-20; Tomahawk, WI.

Treesearch

Ronald M. Teclaw

1996-01-01

Research results and ongoing research activities in field performance of planted trees, seedling propagation, physiology, genetics, acorn germination ,and natural regeneration for oaks are described in 29 abstracts.

Foraging Experiences with Children

ERIC Educational Resources Information Center

Russell, Helen Ross

1976-01-01

Provided are foraging experiences and wild foods information for utilization in the urban school curriculum. Food uses are detailed for roses, dandelions, wild onions, acorns, cattails, violets and mints. (BT)

Protect Taxpayers From ACORN Act

THOMAS, 111th Congress

Sen. Johanns, Mike [R-NE

2009-09-17

Senate - 09/21/2009 Read the second time. Placed on Senate Legislative Calendar under General Orders. Calendar No. 162. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

Protect Taxpayers From ACORN Act

THOMAS, 111th Congress

Sen. Johanns, Mike [R-NE

2009-10-05

Senate - 10/06/2009 Read the second time. Placed on Senate Legislative Calendar under General Orders. Calendar No. 173. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

Protect Taxpayers From ACORN Act

THOMAS, 112th Congress

Sen. Vitter, David [R-LA

2011-01-25

Senate - 01/25/2011 Read twice and referred to the Committee on Homeland Security and Governmental Affairs. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

Temperature Change When Drilling Near the Distal Femoral Physis in a Skeletally Immature Ovine Model.

PubMed

Tenfelde, Allison M; Esquivel, Amanda O; Cracchiolo, Allison M; Lemos, Stephen E

2016-01-01

The possibility of physeal injury during anterior cruciate ligament reconstruction in the pediatric population is a concern. The purpose of this study was to determine whether drilling at or near the physis could cause a temperature increase that could trigger chondrolysis. Skeletally immature cadaveric lamb distal femurs were used for this study and randomly placed in 1 of 6 groups (n=10 in each group). We examined the 8 and 10 mm Flipcutter at a distance of 0.5 mm from the physis and an 8 and 10 mm acorn-tipped reamer at a distance of 0.5 and 3.0 mm from the physis. During drilling, temperature change at the distal femoral physis was continuously measured until the temperature decreased to the original value. An interreamer comparison yielded a significant difference when drilling 0.5 mm from the physis (P=0.001). Pair-wise Mann-Whitney post hoc tests were performed to further evaluate the differences among the groups. The 8 mm FlipCutter had a significantly higher maximum temperature (39.8±1.4°C) compared with the 10 mm FlipCutter (38.0±0.6°C, P=0.001), 8 mm acorn-tipped reamer (38.1±0.9°C, P=0.007), and 10 mm acorn-tipped reamer (37.5±0.3°C, P<0.001). The risk of thermal-induced injury to the physis is low with an all epiphyseal drilling technique, when a traditional acorn-tipped reamer over a guidepin is utilized, even if the drilling occurs very close to the physis. In addition, the risk of drilling with a FlipCutter is low, but may be greater than a traditional reamer. Thermal-induced necrosis is a realistic concern, due to the characteristics of the distal femoral physis, and the propensity for this physis to respond poorly to injury. Our study supports that drilling near the physis can be done safely, although smaller reamers and nontraditional designs may generate higher heat. Level I-basic science.

Soil cover by natural trees in agroforestry systems

NASA Astrophysics Data System (ADS)

Diaz-Ambrona, C. G. H.; Almoguera Millán, C.; Tarquis Alfonso, A.

2009-04-01

The dehesa is common agroforestry system in the Iberian Peninsula. These open oak parklands with silvo-pastoral use cover about two million hectares. Traditionally annual pastures have been grazed by cows, sheep and also goats while acorns feed Iberian pig diet. Evergreen oak (Quercus ilex L.) has other uses as fuelwood collection and folder after tree pruning. The hypothesis of this work is that tree density and canopy depend on soil types. We using the spanish GIS called SIGPAC to download the images of dehesa in areas with different soil types. True colour images were restoring to a binary code, previously canopy colour range was selected. Soil cover by tree canopy was calculated and number of trees. Processing result was comparable to real data. With these data we have applied a dynamic simulation model Dehesa to determine evergreen oak acorn and annual pasture production. The model Dehesa is divided into five submodels: Climate, Soil, Evergreen oak, Pasture and Grazing. The first three require the inputs: (i) daily weather data (maximum and minimum temperatures, precipitation and solar radiation); (ii) the soil input parameters for three horizons (thickness, field capacity, permanent wilting point, and bulk density); and (iii) the tree characterization of the dehesa (tree density, canopy diameter and height, and diameter of the trunk). The influence of tree on pasture potential production is inversely proportional to the canopy cover. Acorn production increase with tree canopy cover until stabilizing itself, and will decrease if density becomes too high (more than 80% soil tree cover) at that point there is competition between the trees. Main driving force for dehesa productivity is soil type for pasture, and tree cover for acorn production. Highest pasture productivity was obtained on soil Dystric Planosol (Alfisol), Dystric Cambisol and Chromo-calcic-luvisol, these soils only cover 22.4% of southwest of the Iberian peninssula. Lowest productivity was

An experimental evaluation of host specificity: The role of encounter and compatibility filters for a rhizocephalan parasite of crabs

USGS Publications Warehouse

Kuris, Armand M.; Goddard, Jeffrey H. R.; Torchin, Mark E.; Murphy, Nicole; Gurney, Robert; Lafferty, Kevin D.

2007-01-01

The encounter/compatibility paradigm of host specificity provides three qualitative pathways to the success or failure of a potential host-parasite interaction. It is usually impossible to distinguish between two of these (encounter and compatibility filters closed versus encounter filter open and compatibility filter closed) because unsuccessful infection attempts are difficult to observe in nature. We were able to open the encounter filter under experimental laboratory conditions. Our analytical system used the rhizocephalan barnacle, Sacculina carcini, a parasitic castrator of the European green crab, Carcinus maenas, and Pachygrapsus marmoratus, a native European crab that occurs with C. maenas but is not parasitized by S. carcini in nature. Penetration followed by unsuccessful infection of P. marmoratus crabs by parasitic barnacle larvae leaves a uniquely permanent record in the thoracic ganglion of the crabs. This provided us with a novel tool to quantify the encounter filter in a host-parasite system in nature. We demonstrated, in the laboratory, that the compatibility filter was closed and that, in nature, even where barnacle larvae were present, the encounter filter was also effectively closed. The closure of both filters in nature explains the failure of this potential host-parasite interaction, an outcome favored by selection in both host and parasite.

Serosurvey for Toxoplasma gondii in arctic foxes and possible sources of infection in the high Arctic of Svalbard.

PubMed

Prestrud, Kristin Wear; Asbakk, Kjetil; Fuglei, Eva; Mørk, Torill; Stien, Audun; Ropstad, Erik; Tryland, Morten; Gabrielsen, Geir Wing; Lydersen, Christian; Kovacs, Kit M; Loonen, Maarten J J E; Sagerup, Kjetil; Oksanen, Antti

2007-11-30

Samples (blood or tissue fluid) from 594 arctic foxes (Alopex lagopus), 390 Svalbard reindeer (Rangifer tarandus platyrhynchus), 361 sibling voles (Microtus rossiaemeridionalis), 17 walruses (Odobenus rosmarus), 149 barnacle geese (Branta leucopsis), 58 kittiwakes (Rissa tridactyla), and 27 glaucous gulls (Larus hyperboreus) from Svalbard and nearby waters were assayed for antibodies against Toxoplasma gondii using a direct agglutination test. The proportion of seropositive animals was 43% in arctic foxes, 7% in barnacle geese, and 6% (1 of 17) in walruses. There were no seropositive Svalbard reindeer, sibling voles, glaucous gulls, or kittiwakes. The prevalence in the arctic fox was relatively high compared to previous reports from canid populations. There are no wild felids in Svalbard and domestic cats are prohibited, and the absence of antibodies against T. gondii among the herbivorous Svalbard reindeer and voles indicates that transmission of the parasite by oocysts is not likely to be an important mechanism in the Svalbard ecosystem. Our results suggest that migratory birds, such as the barnacle goose, may be the most important vectors bringing the parasite to Svalbard. In addition to transmission through infected prey and carrion, the age-seroprevalence profile in the fox population suggests that their infection levels are enhanced by vertical transmission.

Estimating seed crops of conifer and hardwood species

Treesearch

Philip M. McDonald

1992-01-01

Cone, acorn, and berry crops of ponderosa pine (Pinus ponderosa Dougl. ex Laws. var. ponderosa), sugar pine (Pinus lambertiana Dougl.), Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), California white fir (Abies concolor var. lowiana (Gord...

Biological studies on the blue crab Portunus pelagicus and its parasitic infection in Kuwaiti waters.

PubMed

Al-Behbehani, Bahija E

2007-04-01

The study investigated the parasites of symbiotic fauna of the blue crab, Portunus pelagicus and the environmental factors, which was lacking in Kuwait. P. pelagicus feeding habits was studied by examination of the digestive tract. The foregut (stomach) contents of 250 crabs (110 male & 140 female) collected from fish-market, Souq-Sharq, Edelyia capital governorate were investigated. A barnacle, Balanus sp. and staked barnacle Octolasmis sp. (Crustacea: Cirripedia) were found strongly firmly to the carapace, appendages and gills of 30% male crabs and 27% female ones. Endoparasites included unidentified immature trematode stages and nematode larvae in the muscular tissues of both sexes. The main food recovered included molluscs, crustaceans, fish bones and unidentified food materials. The results were reported, photographed and critically discussed.

Are Mussels Always the Best Bioindicators? Comparative Study on Biochemical Responses of Three Marine Invertebrate Species to Chronic Port Pollution.

PubMed

Laitano, María V; Fernández-Gimenez, Analía V

2016-07-01

Bivalves have traditionally been considered good bioindicators due to their sensitivity to pollution, among other features. This characteristic is shared by several other non-bivalve species as well, though studies in this respect remain scarce. This work aims to compare biomarker sensitivity to chronic port pollution among three intertidal invertebrate species with good bioindicator characteristics. Mussels' immunological (phenoloxidase and peroxidases) and biotransformation (glutathione-S-transferase) responses were contrasted against those of limpets and barnacles. The three species under study evidenced activity of all the enzymes measured, although with differences. Barnacle Balanus glandula was the most sensitive species showing pollution modulation of the three enzymes, which suggests that mussels would not always be the best bioindicator species among marine invertebrates depending on the responses that are assessed.

Seventy-five years of masting and rodent population peaks in Norway: Why do wood mice not follow the rules?

PubMed

Selås, Vidar

2016-09-01

Wood mouse (Apodemus sylvaticus) populations are expected to show a peak in autumn in the year after a mast year of sessile oak (Quercus petraea), because stored acorns increase winter survival. In Aust-Agder, South Norway, only 16 of 34 mast years from 1939-2014 were followed by a year with a peak in the wood mouse population. For many of the remaining instances, there rather was a minor peak 2 or 3 years after the mast. In multiple logistic regression models, the probability of a wood mouse population peak after a mast year of sessile oak was positively related to a snow-corrected temperature index of the previous winter and negatively to a small rodent population index of the previous autumn. The present study thus supports the hypothesis that longer periods with snow-free ground and subzero temperatures negatively affect wood mouse winter survival. Because it may be difficult for wood mice to survive on a diet consisting of acorns alone, the negative relationship with the rodent population index of the previous year is most likely caused by an over-exploitation of necessary alternative food resources, such as other plant seeds and arthropods. Stored acorns not utilized during one winter are assumed to benefit wood mice in a succeeding winter, giving a delayed population peak relative to the mast year. © 2016 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

Tests of wildlife habitat models to evaluate oak-mast production

USGS Publications Warehouse

Schroeder, R.L.; Vangilder, L.D.

1997-01-01

We measured oak-mast production and forest structure and composition in the Ozark Mountains of Missouri and tested the accuracy of oak-mast prediction variables from 5 Habitat Suitability Index (HSI) species models. Acorn production was positively associated with several measures of abundance and canopy cover of oak trees, and with an index of mast production for all 5 HSI models. We developed 2 modified oak-mast models, based on inputs related to either oak tree density or oak canopy cover and diversity of oak tree species. The revised models accounted for 22-32% of the variance associated with acorn abundance. Future tests of HSI models should consider: (1) the concept of upper limits imposed by habitat and the effects of nonhabitat factors; (2) the benefits of a top-down approach to model development; and (3) testing models across broad geographic regions.

Two's a crowd? Crowding effect in a parasitic castrator drives differences in reproductive resource allocation in single vs double infections.

PubMed

Fong, Caitlin R; Moron, Nancy A; Kuris, Armand M

2017-04-01

The 'crowding effect' is a result of competition by parasites within a host for finite resources. Typically, the severity of this effect increases with increasing numbers of parasites within a host and manifests in reduced body size and thus fitness. Evidence for the crowding effect is mixed - while some have found negative effects, others have found a positive effect of increased parasite load on parasite fitness. Parasites are consumers with diverse trophic strategies reflected in their life history traits. These distinctions are useful to predict the effects of crowding. We studied a parasitic castrator, a parasite that usurps host reproductive energy and renders the host sterile. Parasitic castrators typically occur as single infections within hosts. With multiple parasitic castrators, we expect strong competition and evidence of crowding. We directly assess the effect of crowding on reproductive success in a barnacle population infected by a unique parasitic castrator, Hemioniscus balani, an isopod parasite that infects and blocks reproduction of barnacles. We find (1) strong evidence of crowding in double infections, (2) increased frequency of double infections in larger barnacle hosts with more resources and (3) perfect compensation in egg production, supporting strong space limitation. Our results document that the effects of crowding are particularly severe for this parasitic castrator, and may be applicable to other castrators that are also resource or space limited.

Research on the nature of recalcitrance in temperate tree seeds: GC and FTIR examinations of stored and desiccated seeds

Treesearch

K.F. Connor; S. Sowa

2002-01-01

Quercus alba L., Q. durandii Buckl., and Q. virginiana Mill. acorns were collected, stored at +4oC and -2oC,and tested monthly to examine the physiological, biochemical, and moisture changes taking place during storage. Aesculus pavia L....

Plankton dynamics and zooplankton carcasses in a mid-latitude estuary and their contributions to the local particulate organic carbon pool

NASA Astrophysics Data System (ADS)

Giesecke, R.; Vallejos, T.; Sanchez, M.; Teiguiel, K.

2017-01-01

Estuaries are among the most productive aquatic ecosystems in coastal areas. Their productivity is linked to the formation of fronts generating mixing and retention of nutrients that can be used by autotrophs. Estuaries exhibit strong thermoclines and haloclines that may significantly affect zooplankton survival, while producing carcasses that could act as an alternative pathway of particulate organic carbon recycling. We investigated the in situ abundance of dead mero- and holozooplankton along the Valdivia River estuary, south-central Chile, during contrasting fresh water discharge conditions (summer, winter and spring), including the potential contribution of zooplankton carcasses to the particulate organic carbon standing stock along the estuary. Zooplankton samples were collected at four stations along the estuary during high tide at the surface, in the pycnocline and below the pycnocline. During autumn and winter the zooplankton community was mostly dominated by copepods, while during summer barnacle nauplii outnumbered copepods fourfold on average. During this study 29.5%±1.8% S.E. of the net-captured zooplankton community, including Acartia tonsa, Paracalanus spp., Oikopleura spp., copepod nauplii, Podon spp. and barnacle nauplii, appeared to have been dead at collection. Highest overall mortality occurred in winter (44±3.1% S.E.), with lower mortality during spring (26±3.8% S.E.) and summer (19±2.7% S.E.). The instantaneous mortality of copepods (Paracalanus spp. and A. tonsa) and copepod naupliar stages was always greater at the surface, associated with brackish water, while dead barnacle nauplii were usually distributed homogenously in the water column. The zooplankton carcass standing stock averaged 0.2 mg C m-3 (in spring and winter) contributing to 0.03-0.22% of the POC produced in the estuary, while in summer carcasses reached up to 2.99 mg C m-3 with a contribution up to 0.87% of the POC. The summer contribution is linked to the presence of

Grains and Starchy Vegetables

MedlinePlus

... Pumpkin Acorn squash Butternut squash Green Peas Corn Beans, Legumes, Peas and Lentils Try to include beans into several meals per week. They are a ... and are loaded with fiber, vitamins and minerals. Beans such as black, kidney, and pinto Bean products ...

Operational Audit Model for a Small Not-for-Profit Organization.

DTIC Science & Technology

1980-06-01

is projected to lose only il0. Presently, they grow kiwi fruit, raspberries, olallieberries, asparagus, banana squash, acorn squash and zucchini...California 93940 0. LT Johnnie Johnson III 2 Procurement Division NTaval Supply Center Oakland, California 94617 7. Henry Flowers 2 Seventh Day

Antioxidant Characterization of Oak Extracts Combining Spectrophotometric Assays and Chemometrics

PubMed Central

Popović, Boris M.; Štajner, Dubravka; Orlović, Saša; Galić, Zoran

2013-01-01

Antioxidant characteristics of leaves, twigs, and acorns from two Serbian oak species Quercus robur L. and Quercus petraea L. from Vojvodina province (northern Serbia) were investigated. 80% ethanol (in water) extracts were used for antiradical power (ARP) determinations against DPPH•, •NO, and O2 •− radicals, ferric reducing antioxidant power (FRAP), total phenol, tannin, flavonoid, and proanthocyanidin contents. Permanganate reducing antioxidant capacity (PRAC) was determined using water extracts. Beside, mentioned parameters, soluble proteins, lipid peroxidation (LP), pigments and proline contents were also determined. The data of different procedures were compared and analyzed by multivariate techniques (correlation matrix calculation and principal component analysis (PCA)). PCA found that investigated organs of two different oak tree species possess similar antioxidant characteristics. The superior antioxidant characteristics showed oak leaves over twigs and acorns and seem to be promising source of antioxidants with possible use in industry and pharmacy. PMID:24453789

Effects of mistletoe (Phoradendron villosum) on California oaks.

PubMed

Koenig, Walter D; Knops, Johannes M H; Carmen, William J; Pesendorfer, Mario B; Dickinson, Janis L

2018-06-01

Mistletoes are a widespread group of plants often considered to be hemiparasitic, having detrimental effects on growth and survival of their hosts. We studied the effects of the Pacific mistletoe, Phoradendron villosum , a member of a largely autotrophic genus, on three species of deciduous California oaks. We found no effects of mistletoe presence on radial growth or survivorship and detected a significant positive relationship between mistletoe and acorn production. This latter result is potentially explained by the tendency of P. villosum to be present on larger trees growing in nitrogen-rich soils or, alternatively, by a preference for healthy, acorn-producing trees by birds that potentially disperse mistletoe. Our results indicate that the negative consequences of Phoradendron presence on their hosts are negligible-this species resembles an epiphyte more than a parasite-and outweighed by the important ecosystem services mistletoe provides. © 2018 The Author(s).

Comprehensive Assessment of Marine Coatings in the Laboratory and Field

DTIC Science & Technology

2015-03-27

basal plate morphology and minimum size requirements. Only barnacles occurring at least 5 mm from the edges of the coupon were tested. Other...Incipient Fouling Calcareous Polychaetes | Sedimentan/ Polychaetes Solitary Tunicate | Sponges |Scuzz & & & & & Figure 7. Average

Emergy analysis of a silvo-pastoral system, a case study in southern Portugal

EPA Science Inventory

The Mediterranean silvo-pastoral system known as Montado, in Portugal, is a complex land use system composed of an open tree stratum in various densities and an herbaceous layer, used for livestock grazing. Livestock also profit from the acorns, and the grazing contributes to avo...

Food preferences of captive wild raccoons, Procyon lotor, from east Texas

Treesearch

James F. Taulman; James H. Williamson

1994-01-01

We offered a random assortment of six foods to nine captive raccoons (Procyon lotor) during 10 days in February 1991 and to 10 raccoons during 9 days in January 1992; persimmon (Diospyros virginianus); southern red oak acorn (Quercus falacata); chicken egg; crayfish (Cambarus bartoni);...

Bioassays and field immersion tests: a comparison of the antifouling activity of copper-free poly(methacrylic)-based coatings containing tertiary amines and ammonium salt groups.

PubMed

Bressy, C; Hellio, C; Marechal, J P; Tanguy, B; Margaillan, A

2010-10-01

This paper focuses on the activity spectrum of three dimethylalkyl tertiary amines as potential active molecules and the corresponding ammonium salt-based antifouling (AF) paints. Bioassays (using marine bacteria, microalgae and barnacles) and field tests were combined to assess the AF activity of coatings. Bioassay results demonstrated that the ammonium salt-based paints did not inhibit the growth of microorganisms (except the dimethyldodecylammonium-based coatings) and that the tertiary amines were potent towards bacteria, diatoms, and barnacle larvae at non-toxic concentrations (therapeutic ratio, LC50/EC50, <1). The results from field tests indicated that the ammonium salt-based coatings inhibited the settlement of macrofouling and the dimethylhexadecylammonium-based coatings provided protection against slime in comparison with PVC blank panels. Thus, results from laboratory assays did not fully concur with the AF activity of the paints in the field trial.

First 3D reconstruction of the rhizocephalan root system using MicroCT

NASA Astrophysics Data System (ADS)

Noever, Christoph; Keiler, Jonas; Glenner, Henrik

2016-07-01

Parasitic barnacles (Cirripedia: Rhizocephala) are highly specialized parasites of crustaceans. Instead of an alimentary tract for feeding they utilize a system of roots, which infiltrates the body of their hosts to absorb nutrients. Using X-ray micro computer tomography (MicroCT) and computer-aided 3D-reconstruction, we document the spatial organization of this root system, the interna, inside the intact host and also demonstrate its use for morphological examinations of the parasites reproductive part, the externa. This is the first 3D visualization of the unique root system of the Rhizocephala in situ, showing how it is related to the inner organs of the host. We investigated the interna from different parasitic barnacles of the family Peltogastridae, which are parasitic on anomuran crustaceans. Rhizocephalan parasites of pagurid hermit crabs and lithodid crabs were analysed in this study.

Removal of ice and marine growth from ship surfaces: A concept

NASA Technical Reports Server (NTRS)

Bauman, A. J.

1975-01-01

Proposed surface is structured from sections of low-melting-point alloy. Sections are separated by network of passages for compressed air. Ice or barnacles are removed by passing electrical current through alloy and bursts of compressed air through passages.

Blue and Valley Oak Seedling Establishment on California's Hardwood Rangelands

Treesearch

Theodore E. Adams Jr.; Peter B. Sands; William H. Weitkamp; Neil K. McDougald

1991-01-01

Factors contributing to poor establishment of blue oak (Quercus douglasii) and valley oak (Q. lobata) in California oak-grassland savannas were studied in a series of acorn seeding experiments initiated in 1985. Exclusion of large herbivores permitted examination of herbaceous interference and small mammal and insect depredation....

Food habits of the raccoon in eastern Texas

USGS Publications Warehouse

Baker, R.H.; Newman, C.C.; Wilke, F.

1945-01-01

The food habits of raccoons were studied along the Neches River in three counties of eastern Texas in 1940-42. Field studies mere supplemented by laboratory analyses of 344 scats collected in all months and of 23 stomachs and 11 intestines obtained in winter. Acorns and crayfish constitute more than half of the yearly diet and both are consumed in considerable amount at all seasons. Persimmons and grapes were utilized heavily when available and other fruits in smaller amounts. Insects and other invertebrates formed an important part of the diet. Vertebrates were eaten sparingly but species of water snakes were preyed upon as were winter and spring concentrations of water fowl.....Raccoons were found to concentrate in timbered river bottoms during the winter and spring, feeding largely on acorns and crayfish. Under these conditions they are readily trapped. In the summer and autumn the populations appear to be dispersed through the uplands as well as bottomlands in search of seasonal foods.

Sea-Based X-Band (SBX) Radar Vessel Maintenance and Repair. Draft Environmental Assessment

DTIC Science & Technology

2011-02-14

crabs, lobsters, and shrimp), amphipods (small shrimp-like creatures), bivalves, barnacles, and gastropods (snails and slugs). Less common groups...A second phase will cover implementation of 10 years of post construction monitoring and adaptive management. Future 1 4.0 Cumulative Impacts

Long-distance Movements by Female White-footed Mice, Peromyscus leucopus, in Extensive Mixed-wood Forest

Treesearch

Thomas J. Maier

2002-01-01

Two adult female White-footed Mice (Peromyscus leucopus) were recovered 14,730 m and 6840 m from where they were originally captured and tagged in central Massachusetts. Similar combinations of factors throughout an extensive forested landscape, including poor acorn (Quercus spp.) crops, high population densities of mice, and the...

Root susceptibility and inoculum production from roots of Eastern United States oak species to Phytophthora ramorum

USDA-ARS?s Scientific Manuscript database

Little is known about root susceptibility of eastern U.S. tree species to Phytophthora ramorum. In this study, we examined root susceptibility and inoculum production from roots. Sprouted acorns of Q. rubra, Q. palustrus, Q. coccinia, Q. alba, Q. michauxii and Q. prinus were exposed to motile zoos...

Combined effects of cotyledon excision and nursery fertilization on root growth, nutrient status and outplanting performance of Quercus variabilis container seedlings.

PubMed

Shi, Wenhui; Bloomberg, Mark; Li, Guolei; Su, Shuchai; Jia, Liming

2017-01-01

Artificial excision of the distal part of acorns in order to promote germination is well researched in oak seedling cultivation studies. However, studies of combined effects of cotyledon excision and nursery fertilization on container seedlings are lacking, especially for seedling root growth and outplanting performance. This study aimed to explore the main effects of cotyledon excision on Quercus variabilis seedling emergence characteristics and demonstrated the combined effects of cotyledon excision and nursery fertilization on seedling quality to improve Quercus variabilis seedling outplanting performance. Four cotyledon excision treatments and two classes of nursery fertilization were implemented. Seedling emergence was noted every week after sowing. Seedling dry mass, morphology, and nutrient status were assessed at the end of the nursery season. After the first outplanting season, the aforementioned measurements along with seedling survival were determined once again. The results showed that cotyledon excision generally induced greater and more rapid seedling emergence, but did not affect shoot emergence synchronicity. The highest total emergence and emergence rate occurred with Intermediate excision (1/2 of the distal end of acorn was excised). Effects of nutrient loss due to cotyledon excision on seedling quality and outplanting performance were somewhat compensated by nursery fertilization. Nursery fertilization promoted dry mass increment (the net increment from T0 to T2 for dry mass) for excised seedlings after outplanting, resulting in better performance for Slight (1/3 of the distal end of acorn was excised) and Intermediate excision treatments in the field. Thus we conclude Intermediate excision combined with reasonable nursery fertilization can be recommended for production of nursery grown seedlings for afforestation.

Combined effects of cotyledon excision and nursery fertilization on root growth, nutrient status and outplanting performance of Quercus variabilis container seedlings

PubMed Central

Shi, Wenhui; Bloomberg, Mark; Li, Guolei; Su, Shuchai; Jia, Liming

2017-01-01

Artificial excision of the distal part of acorns in order to promote germination is well researched in oak seedling cultivation studies. However, studies of combined effects of cotyledon excision and nursery fertilization on container seedlings are lacking, especially for seedling root growth and outplanting performance. This study aimed to explore the main effects of cotyledon excision on Quercus variabilis seedling emergence characteristics and demonstrated the combined effects of cotyledon excision and nursery fertilization on seedling quality to improve Quercus variabilis seedling outplanting performance. Four cotyledon excision treatments and two classes of nursery fertilization were implemented. Seedling emergence was noted every week after sowing. Seedling dry mass, morphology, and nutrient status were assessed at the end of the nursery season. After the first outplanting season, the aforementioned measurements along with seedling survival were determined once again. The results showed that cotyledon excision generally induced greater and more rapid seedling emergence, but did not affect shoot emergence synchronicity. The highest total emergence and emergence rate occurred with Intermediate excision (1/2 of the distal end of acorn was excised). Effects of nutrient loss due to cotyledon excision on seedling quality and outplanting performance were somewhat compensated by nursery fertilization. Nursery fertilization promoted dry mass increment (the net increment from T0 to T2 for dry mass) for excised seedlings after outplanting, resulting in better performance for Slight (1/3 of the distal end of acorn was excised) and Intermediate excision treatments in the field. Thus we conclude Intermediate excision combined with reasonable nursery fertilization can be recommended for production of nursery grown seedlings for afforestation. PMID:28545103

High Rates of Gene Flow by Pollen and Seed in Oak Populations across Europe

PubMed Central

Gerber, Sophie; Chadœuf, Joël; Gugerli, Felix; Lascoux, Martin; Buiteveld, Joukje; Cottrell, Joan; Dounavi, Aikaterini; Fineschi, Silvia; Forrest, Laura L.; Fogelqvist, Johan; Goicoechea, Pablo G.; Jensen, Jan Svejgaard; Salvini, Daniela; Vendramin, Giovanni G.; Kremer, Antoine

2014-01-01

Gene flow is a key factor in the evolution of species, influencing effective population size, hybridisation and local adaptation. We analysed local gene flow in eight stands of white oak (mostly Quercus petraea and Q. robur, but also Q. pubescens and Q. faginea) distributed across Europe. Adult trees within a given area in each stand were exhaustively sampled (range [239, 754], mean 423), mapped, and acorns were collected ([17,147], 51) from several mother trees ([3], [47], 23). Seedlings ([65,387], 178) were harvested and geo-referenced in six of the eight stands. Genetic information was obtained from screening distinct molecular markers spread across the genome, genotyping each tree, acorn or seedling. All samples were thus genotyped at 5–8 nuclear microsatellite loci. Fathers/parents were assigned to acorns and seedlings using likelihood methods. Mating success of male and female parents, pollen and seed dispersal curves, and also hybridisation rates were estimated in each stand and compared on a continental scale. On average, the percentage of the wind-borne pollen from outside the stand was 60%, with large variation among stands (21–88%). Mean seed immigration into the stand was 40%, a high value for oaks that are generally considered to have limited seed dispersal. However, this estimate varied greatly among stands (20–66%). Gene flow was mostly intraspecific, with large variation, as some trees and stands showed particularly high rates of hybridisation. Our results show that mating success was unevenly distributed among trees. The high levels of gene flow suggest that geographically remote oak stands are unlikely to be genetically isolated, questioning the static definition of gene reserves and seed stands. PMID:24454802

Effect of truncated cone roughness element density on hydrodynamic drag

NASA Astrophysics Data System (ADS)

Womack, Kristofer; Schultz, Michael; Meneveau, Charles

2017-11-01

An experimental study was conducted on rough-wall, turbulent boundary layer flow with roughness elements whose idealized shape model barnacles that cause hydrodynamic drag in many applications. Varying planform densities of truncated cone roughness elements were investigated. Element densities studied ranged from 10% to 79%. Detailed turbulent boundary layer velocity statistics were recorded with a two-component LDV system on a three-axis traverse. Hydrodynamic roughness length (z0) and skin-friction coefficient (Cf) were determined and compared with the estimates from existing roughness element drag prediction models including Macdonald et al. (1998) and other recent models. The roughness elements used in this work model idealized barnacles, so implications of this data set for ship powering are considered. This research was supported by the Office of Naval Research and by the Department of Defense (DoD) through the National Defense Science & Engineering Graduate Fellowship (NDSEG) Program.

Effects of microplastics on sessile invertebrates in the eastern coast of Thailand: An approach to coastal zone conservation.

PubMed

Thushari, Gajahin Gamage Nadeeka; Senevirathna, Jayan Duminda Mahesh; Yakupitiyage, Amararatne; Chavanich, Suchana

2017-11-15

This study assessed the microplastic contamination of 3 most abundant sessile and intertidal invertebrates (Rock Oyster: Saccostrea forskalii, Striped Barnacle: Balanus amphitrite, Periwinkle: Littoraria sp.) in 3 beaches of the eastern coasts of Thailand. The results showed a significant accumulation of microplastics in the invertebrates at rates of 0.2-0.6 counts/g indicating higher pollution levels along the coastline. Filter feeding organisms showed comparatively higher accumulation rates of microplastics. Thus, contaminated bivalves pose potential health risks for seafood consumers. The plastic pollutant prevalence in sessile and intertidal communities was corresponded with pollution characteristics of contaminated beach habitats where they live. Thus, bivalves, gastropods and barnacles can be used as indicators for contamination of microplastics in the areas. This study also demonstrated the need for controlling plastic pollution in Thai coastal areas. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Scargill, James H. C.

Theories with more than one vacuum allow quantum transitions between them, which may proceed via bubble nucleation; theories with more than two vacua posses additional decay modes in which the wall of a bubble may further decay. The instantons which mediate such a process have O(3) symmetry (in four dimensions, rather than the usual O(4) symmetry of homogeneous vacuum decay), and have been called ‘barnacles’; previously they have been studied in flat space, in the thin wall limit, and this paper extends the analysis to include gravity. It is found that there are regions of parameter space in which, givenmore » an initial bubble, barnacles are the favoured subsequent decay process, and that the inclusion of gravity can enlarge this region. The relation to other heterogeneous vacuum decay scenarios, as well as some of the phenomenological implications of barnacles are briefly discussed.« less

The Hardware Game: Sorting the Winners from the Losers.

ERIC Educational Resources Information Center

Dyrli, Odvard Egil

1984-01-01

Reviews companies to help educators make decisions in selecting microcomputers. Companies include Acorn, Apple, Atari, Coleco, Commodore, Franklin, IBM, Radio Shack, Texas Instruments, and Timex. Indicates that educators cannot simply look for the best deals but need to look at companies that are serious about long-term involvement in quality…

The Relationship Between Basal Area and Hard Mast Production in the Ouachita Mountains

Treesearch

Roger W. Perry; Ronald E. Thill; Philip A. Tappe; David G. Peitz

2004-01-01

Abstract - Because the relationship between stand density and hard mast production is not clear, we investigated the effects of varying total overstory basal area (BA) on acorn and hickory nut production in the Ouachita Mountains. We used Whitehead visual surveys to estimate mast production in oaks (Quercus spp.) and hickories (...

Afforesting agricultural lands in the Mississippi Alluvial Valley (USA): effects of silvicultural methods on understory plant diversity

Treesearch

Diane De Steven; Callie J. Schweitzer; Steven C. Hughes; John A. Stanturf

2015-01-01

To compare methods for bottomland hardwood reforestation on marginal farmlands in the Mississippi Alluvial Valley, four afforestation treatments (natural colonization, sown oak acorns, planted oak seedlings, cottonwood–oak interplant) were established in 1995 on former soybean cropland. Natural, sown, and planted-oak plots were not managed after establishment....

77 FR 3319 - TapSlide, Inc., TTC Technology Corp. (f/k/a SmarTire Systems Inc.), TWL Corp., TXP Corp...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-23

... SECURITIES AND EXCHANGE COMMISSION [File No. 500-1] TapSlide, Inc., TTC Technology Corp. (f/k/a SmarTire Systems Inc.), TWL Corp., TXP Corp., Valentec Systems, Inc. (f/k/a Acorn Holdings Corp... current and accurate information concerning the securities of TTC Technology Corp. (f/k/a SmarTire Systems...

An Archeological Overview and Management Plan for the Louisiana Army Ammunition Plant, Bossier and Webster Parishes, Louisiana.

DTIC Science & Technology

1984-08-06

and miscellaneous items. Dominant hard- woods produce nuts such as acorns and hickories. Blueberries , black- berries, grapes, persimmons, plums, and...Valley cultures and later with Caddoan. Both 7-1 PI(EDING PACE BL"_- io FLmD ]1 0115D-2 historic Caddo and Choctaw are documo.nted in northwestern

A comparison of the survival and development of the seedlings of four upland oak species grown in four different understory light environments

Treesearch

Patrick Brose; Joanne Rebbeck

2017-01-01

Oak (Quercus spp.) research and management often focus on northern red oak (Quercus rubra) and assume that associated upland oaks have similar growth patterns. To test this premise, we measured the survival and development of four species of acorn-origin oak seedlings growing in four different levels of understory sunlight for...

Lithocarpus densiflorus (Hook. & Arn.) Rehd. tanoak

Treesearch

John C. Tappeiner; Philip M. McDonald; Douglass F. Roy

1990-01-01

Tanoak (Lithocarpus densiflorus), also called tanbark-oak, is an evergreen hardwood that, with other species in the genus, is considered a link between the chestnut, Castanea, and the oak, Quercus (19). Tanoak has flowers like the chestnut and acorns like the oak. This medium-sized tree grows best on the...

Nuttall Oak Direct Seedings Still Successful After 11 Years

Treesearch

Robert L. Johnson

1983-01-01

Forty-five hundred acorns of Nuttall oak (Quercus nuttallii Palmer) were either machine or manually sown at 2-, 4-, or 6-inch depths in a 20-acre, intensively site-prepared clearing within the Delta Experimental Forest located near Stoneville, Mississippi. Field germination averaged 36 percent; no significant differences in germination appeared...

Geographic patterns of variation in biomass production of California blue oak seedlings as a response to water availability

Treesearch

Susan Kloss; Joe R. McBride

2002-01-01

This study characterized the distribution of geographic variation in water relations traits for six populations of California blue oak along a precipitation gradient (two each from high, medium and low precipitation environments). Acorns were collected from each population, germinated and the resulting seedlings were experimentally treated with three different watering...

Variation in flood tolerance of container-grown seedlings of swamp white oak, bur oak, and white oak

Treesearch

Michael P. Walsh; J.W. Van Sambeek; Mark V. Coggeshall

2008-01-01

How much variation in flood tolerance exists among seedlings within oak species, given the flood frequency of sites from which acorns are collected, has been largely unexplored. Our studies examined initial growth and flood tolerance for seedlings of swamp white oak (Quercus bicolor Willd.), bur oak (Q. macrocarpa L.), and white...

Nature Study Tips: Native American Foods.

ERIC Educational Resources Information Center

Russell, Helen Ross

1984-01-01

Discusses Native American foods, focusing on Native American cultivated crops, methods of cooking, and methods of preserving food. Includes suggestions for 19 classroom activities, including collecting wild plants used as food, gathering/drying and eating various wild plants and plant products (such as acorns and corn), and making a garden. (JN)

Crown class dynamics of oaks after commercial thinning in West Virginia: 30-year results

Treesearch

Gary W. Miller; Jamie L. Schuler; James S. Rentch

2017-01-01

Commercial thinning in hardwood stands is generally applied to reduce overcrowding and to favor the development of desired residual species until the stand is mature. In mixed hardwood stands, commercial thinning also provides an opportunity to promote vigorous overstory oaks (Quercus spp.) that will serve as sources of acorns and advanced...

Comparing regeneration techniques for afforesting previously farmed bottomland hardwood sites in the Lower Mississippi Alluvial Valley, USA

Treesearch

Brian Roy Lockhart; Bob Keeland; John McCoy; Thomas J. Dean

2003-01-01

A study was implemented to test site preparation methods and artificial regeneration of three oak (Quercus spp.) species on four agricultural fields in the Lower Mississippi Alluvial Valley in Louisiana, USA. Six years after establishment, few consistent differences were found in oak density between sowing acorn methods (seed drill versus broadcast...

Cirripede Cypris Antennules: How Much Structural Variation Exists Among Balanomorphan Species from Hard-Bottom Habitats?

PubMed

Chan, Benny K K; Sari, Alireza; Høeg, Jens T

2017-10-01

Barnacle cypris antennules are important for substratum attachment during settlement and on through metamorphosis from the larval stage to sessile adult. Studies on the morphology of cirripede cyprids are mostly qualitative, based on descriptions from images obtained using a scanning electron microscope (SEM). To our knowledge, our study is the first to use scanning electron microscopy to quantify overall structural diversity in cypris antennules by measuring 26 morphological parameters, including the structure of sensory organs. We analyzed cyprids from seven species of balanomorphan barnacles inhabiting rocky shore communities; for comparison, we also included a sponge-inhabiting balanomorphan and a verrucomorphan species. Multivariate analysis of the structural parameters resulted in two distinct clusters of species. From nonmetric multidimensional scaling plots, the sponge-inhabiting Balanus spongicola and Verruca stroemia formed one cluster, while the other balanomorphan species, all from hard bottoms, grouped together in the other cluster. The shape of the attachment disk on segment 3 is the key parameter responsible for the separation into two clusters. The present results show that species from a coastal hard-bottom habitat may share a nearly identical antennular structure that is distinct from barnacles from other habitats, and this finding supports the fact that such species also have rather similar reactions to substratum cues during settlement. Any differences that may be found in settlement biology among such species must therefore be due either to differences in the properties of their adhesive mechanisms or to the way that sensory stimuli are detected by virtually identical setae and processed into settlement behavior by the cyprid.

Seascapes: Glimpses of Our Water World.

ERIC Educational Resources Information Center

Hardin, Jan

Presented is a collection of newspaper articles prepared by the Delaware Sea Grant Marine Advisory Service during the summer of 1978. Subjects addressed are bioluminescence, beachcomber finds, gulls, beach erosion, marine research activities, barnacles, sand, seaweed, jellyfish, shore restaurants, diving mammals, and tides. (Author/BW)

Multi-User Facilities for Molecular Marine Biology and Biotechnology

DTIC Science & Technology

1990-04-06

relatedness (or non-relatedness) of symbiotic zooxanthellae in corals. The DNA synthesizer is used to prepare universal primers for 18s r RNA. A...tunicates (Weissman lab) Robert Rowan - Zooxanthellae (Powers lab) Lani West - sponges/barnacles (Powers lab) Jeff Mitton - Mytilus (Powers lab) Kristi

Evaluation of Nuttall oak and cherrybark oak survival by planting stock and site preparation treatment type in a WRP planting on a retired agricultural site

Treesearch

Andrew B. Self; Andrew W. Ezell; Andrew J. Londo; John D. Hodges

2010-01-01

Oaks are an ecologically and economically important component of the southern landscape, and many landowners are opting to regenerate their lands with these species. Federal cost share programs, such as the Wetland Reserve Program (WRP), have increased public interest in afforestation of retired agricultural sites in the Lower Mississippi Alluvial Valley (LMAV). Acorns...

Seeding and planting upland oaks

Treesearch

T. E. Russell

1971-01-01

Upland oaks can be established by seeding or planting, but additional experience is needed before these methods become economical alternatives to natural regeneration. Recently forested sites are generally more favorable than abandoned fields. Lack of repellents to protect acorns from animals severely limits direct seeding, but oaks can be planted readily by...

Growth And Development Of First-Year Nursery-Grown White Oak Seedlings Of Individual Mother Trees

Treesearch

Shi-Jean S. Sung; Paul P. Kormanik; Stanley J. Zarnoch

2002-01-01

Abstract - White oak (Quercus alba L.) acorns from individual mother trees at Arrowhead Seed Orchard (ASO, Milledgeville, GA), Beech Creek Seed Orchard (BSO, Murphy, NC), and Savannah River Site (SRS, Aiken, SC) were sown in December 1999 at Whitehall Experiment Forest Nursery (Athens, GA). All 6 mother trees from BSO were grafted...

Responsive Reading: Caring for Chicken Little

ERIC Educational Resources Information Center

Maderazo, Catherine

2009-01-01

Media images and news about current events have the potential to strike like acorns. In these moments, children, like Chicken Little, need caring adults who can help them understand what is happening. As early childhood educators, one must recognize and provide opportunities to guide children's social and emotional well-being in addition to…

Thinning – a tool for restoration of California's Southern Sierra Nevada blue oak woodlands

Treesearch

Richard B. Standiford; Ralph L. Phillips; Neil K. McDougald

2015-01-01

Fire frequency on a blue oak (Quercus douglasii) dominated rangeland in California's southern Sierra Nevada foothills was approximately every 10 years until 1965, followed by a 30 year period of fire exclusion. This resulted in a dense tree overstory with small diameters, high crown cover, poor acorn and forage production, and limited...

Factors Limiting the Establishment of a Chaparral Oak, Quercus durata Jeps., in Grassland

Treesearch

Kimberlyn Williams; Stephen D. Davis; Barbara L. Gartner; Staffan Karlsson

1991-01-01

We studied factors that restrict colonization of grassland by Quercus durata Jeps., an oak commonly found in chaparral on serpentine soils. The study site contained a chaparral/ grassland border that had been stable for at least 50 years. Monitoring of acorns planted in the chaparral understory and grassland revealed that, although initial seedling...

Response of sun-grown and shade-grown northern red oak seedlings to outplanting in clearcuts and shelterwoods in North Alabama

Treesearch

Callie Jo Schweitzer; Emile S. Gardiner; David L. Loftis

2006-01-01

The primary objective of this study was to determine if greenhouse light environment would affect outplanting success for northern red oak (Quercus rubra L.) in clearcuts and shelterwoods. In 2002, northern red oak seedlings were grown from acorns under full-ambient (sun) and half-ambient (shade) light conditions in a greenhouse. Seedlings grown...

Evaluation of Glider Coatings against Biofouling for Improved Flight Performance

DTIC Science & Technology

2010-09-30

the different stages of settlement, attachment and fouling release to be studied in detail. This is especially important, as the key to antifouling (ie... antifouling coatings. Biofouling 10: 187-197. Swain, G.W. et al. (2000) Biofouling and barnacle adhesion data for fouling-release coatings subjected

Spatial and geographical changes in the mesozooplankton community in the Bering and Chukchi Seas during the summers of 2007 and 2008

NASA Astrophysics Data System (ADS)

Matsuno, Kohei; Landeira Sanchez, Jose M.; Yamaguchi, Atsushi; Hirawake, Toru; Kikuchi, Takashi

2016-09-01

From July to August 2007 and June to July 2008, the horizontal/geographical changes in the zooplankton community in the Bering and Chukchi Seas were studied. The geographical patterns, which were common for these two years, were observed for salinity, chlorophyll a (Chl. a), zooplankton chaetognaths, hydrozoans and the whole zooplankton community. Among them, the patterns of salinity and Chl. a were related with the horizontal distribution of the water masses. The distributions of the two carnivorous taxa were correlated with their prey (copepods or barnacle larvae). The analysis of the structural equation model (SEM) revealed that the horizontal distribution of the zooplankton abundance and biomass were governed by the different taxa. Thus, the zooplankton abundance was governed by the numerically dominant but smaller-bodied taxa, such as the barnacle larvae and copepod Pseudocalanus spp., while the zooplankton biomass was determined by the large-bodied copepods, such as Calanus glacialis/marshallae and Eucalanus bungii.

Assessment of heavy metal and petroleum hydrocarbon contamination in the Sultanate of Oman with emphasis on harbours, marinas, terminals and ports.

PubMed

Jupp, Barry P; Fowler, Scott W; Dobretsov, Sergey; van der Wiele, Henk; Al-Ghafri, Ahmed

2017-08-15

The assessment here includes data on levels of contaminants (petroleum hydrocarbons and heavy metals) in sediments and biomonitor organisms, including the eulittoral rock oyster Saccostrea cucullata and subtidal biomonitors, the barnacle Balanus trigonus and the antipatharian coral Antipathes sp., at harbours, marinas, terminals and large ports along the coastline of Oman. TBT levels in harbour and port sediments up to a maximum of 100ppb TBT dry weight are highlighted. Oysters contained concentrations up to 367ppm mg TPH/kg dry weight. The maximum levels of Cd, Cu, Pb and Zn were found in the subtidal sediments and barnacles at the oil tanker loading Single Buoy Mooring stations in Mina Al Fahal. In general, the levels of most of the contaminants analysed are at low to moderate concentrations compared to those in highly contaminated sites such as shipyards and dry docks, but continued monitoring is recommended especially during any dredging campaigns. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of prolonged entanglement in discarded fishing gear with substantive biofouling on the health and behavior of an adult shortfin mako shark, Isurus oxyrinchus.

PubMed

Wegner, Nicholas C; Cartamil, Daniel P

2012-02-01

A mature male shortfin mako, Isurus oxyrinchus, was captured with a three-strand twisted natural fiber rope wrapped around the body causing deep abrasions, scoliosis of the back, and undernourishment. Fifty-two pelagic peduculate barnacles from four species were found fouling on the rope. Assuming larval settlement occurred following entanglement, barnacle growth-rate data suggest the rope had been around the shark for at least 150 days. However, the onset of severe scoliosis (likely linked to the increased constriction of the rope with growth and the added drag induced by biofouling) indicates that this rope may have been in place much longer. Following removal of the rope, a pop-up satellite archival tag was attached to the shark to assess post-release health. The resulting 54 days of tag deployment data show that despite its injuries, the shark survived, and following an initial stress period, exhibited movement patterns characteristic of healthy makos. Copyright © 2011 Elsevier Ltd. All rights reserved.

Quality assurance and control issues for HF radar wave and current measurements

NASA Astrophysics Data System (ADS)

Wyatt, Lucy

2015-04-01

HF radars are now widely used to provide surface current measurements over wide areas of the coastal ocean for scientific and operational applications. In general data quality is acceptable for these applications but there remain issues that impact on the quantity and quality of the data. These include problems with calibration and interference which impact on both phased array (e.g. WERA, Pisces) and direction-finding (e.g. SeaSonde) radars. These same issues and others (e.g. signal-to-noise, in-cell current variability, antenna sidelobes) also impact on the quality and quantity of wave data that can be obtained. These issues will be discussed in this paper, illustrated with examples from deployments of WERA, Pisces and SeaSonde radars in the UK, Europe, USA and Australia. These issues involve both quality assurance (making sure the radars perform to spec and the software is fully operational) and in quality control (identifying problems with the data due to radar hardware or software performance issues and flagging these in the provided data streams). Recommendations for the former, and current practice (of the author and within the Australian Coastal Ocean Radar Network, ACORN*) for the latter, will be discussed. The quality control processes for wave measurement are not yet as well developed as those for currents and data from some deployments can be rather noisy. Some new methods, currently under development by SeaView Sensing Ltd and being tested with ACORN data, will be described and results presented. *ACORN is a facility of the Australian Integrated Marine Observing System, IMOS. IMOS is a national collaborative research infrastructure, supported by Australian Government. It is led by University of Tasmania in partnership with the Australian marine and climate science community.

Evaluation of site preparation and planting stock on nuttall oak and cherrybark oak growth on a former agriculture area

Treesearch

Andrew B. Self; Andrew W. Ezell; Andrew J. Londo; John D. Hodges; Derek K. Alkire

2012-01-01

Oaks are an important component of the southern landscape, and are planted on thousands of acres across the region annually. Federal cost share programs, such as the Wetland Reserve Program (WRP), have increased public interest in afforestation of retired agricultural sites in the Lower Mississippi Alluvial Valley. Acorns, bare root, containerized, and potted seedlings...

Growth and development of planted northern red oak on bulldozed skidroads after clearcutting in Appalachian hardwoods

Treesearch

James N. Kochenderfer; Mary Beth Adams; Gary W. Miller; Frederica Wood

2006-01-01

Artificial regeneration of northern red oak in Appalachian clearcuts on mesic sites is hindered by accessibility and competition from developing vegetation. The use of skidroads as a planting medium was evaluated on two clearcuts with contrasting aspects in north central West Virginia. Stratified acorns were planted in tree shelters at three positions (cut, middle,...

Midstory removal methods tested for timely release of newly established oak seedlings under oak shelterwoods

Treesearch

Ronald A. Rathfon

2011-01-01

The oak shelterwood method calls for the removal of shade-tolerant, undesirable midstory species to create adequate diffuse light conditions at the forest floor for oak seedling establishment, preferably timed to coincide with a large acorn crop. Injection (INJ) with an herbicide, chainsaw felling and girdling with herbicide application (SAW), and a low-volume basal...

The Early Years: Fostering Environmental Stewardship

ERIC Educational Resources Information Center

Ashbrook, Peggy

2016-01-01

For young children, a found acorn, stone, or lichen-covered branch can be a touchstone of an experience in nature. Children, however, should also be taught to "leave no trace." As the National Park Service advocates, visitors to natural areas should "Preserve the sense of discovery for others by leaving all natural and cultural…

Restoring California black oak ecosystems to promote tribal values and wildlife

Treesearch

Jonathan W. Long; M. Kat Anderson; Lenya Quinn-Davidson; Ron W. Goode; Frank K. Lake; Carl N. Skinner

2016-01-01

This report synthesizes information to help promote the distinctive ecological and cultural benefits provided by California black oak. Production of abundant, high-quality acorns desired by Native Americans in California, as well as other valued services, requires the presence of mature, broad-crowned trees with low fuel levels and low pest levels. Although black oaks...

Ten years of oak restoration in city of Walnut Creek open spaces

Treesearch

Ralph Kraetsch

2002-01-01

The Oak Habitat Restoration Project began in 1991 when several individuals recognized that the oak woodlands and savannas of Walnut Creek's nearly 2,800 acres of open spaces had little natural regeneration. This group gathered volunteers who harvested acorns, planted them, and then installed tree shelters and watered the resulting seedlings. The Project soon...

Factors Affecting Seedling Survivorship of Blue Oak (Quercus douglasii H. & A.) in Central California

Treesearch

Frank W. Davis; Mark Borchert; L. E. Harvey; Joel C. Michaelsen

1991-01-01

Blue oak seedling mortality was studied in relation to vertebrate predators, initial acorn planting position, slope and aspect, and oak canopy cover at two sites in the Central Coast Ranges of California. Seedling survival rates (Psd) were related to treatment variables using logistic regression analysis. Analysis of 2842 seedlings for 3 years following establishment...

Testing for Seed Quality in Southern Oaks

Treesearch

F.T. Bonner

1984-01-01

Expressions of germination rate, such as peak value (PV) or mean germination time (MGT), provide good estimates of acorn quality, but test completion requires a minimum of 3 weeks. For more rapid estimates, tetrazolium staining is recommended. Some seed test results were significantly correlated with nursery germination of cherrybark and water oaks, but not with...

Minimum Input Techniques for Valley Oak Restocking

Treesearch

Elizabeth A. Bernhardt; Tedmund J. Swiecki

1991-01-01

We set up experiments at four locations in northern California to demonstrate minimum input techniques for restocking valley oak, Quercus lobata. Overall emergence of acorns planted in 1989 ranged from 47 to 61 percent. Use of supplemental irrigation had a significant positive effect on seedling growth at two of three sites. Mulch, of organic...

Impact of soil scarification on the composition of regeneration and species diversity in an oak shelterwood

Treesearch

James J. Zaczek; Joseph Harding; James Welfley

1997-01-01

This study was conducted in a fenced 1-yr-old 70-acre mixed-oak shelterwood to determine the impact of soil scarification on species composition and the production of oak regeneration from abundant northern red oak (Quercus rubra L.) acorns. In October 1993, seven replicates were established and randomly divided into control and scarified plots....

Direct Seeding Scarlet Oak in the North Carolina Mountains

Treesearch

Earl R. Sluder

1965-01-01

Seedling establishment rates varied from 0 to 50 percent in a direct seeding study with scarlet oak (Quercus coccinea Muenchh.) on the Bent Creek Experimental Forest near Asheville, North Carolina. Acorns planted 2 inches deep in the spring with screen protection produced the most seedlings; those surface sown without screens in the spring or fall...

Growth and seed production of sawtooth oak (`quercus acutissima`) 22 years after direct seeding. Forest Service research note

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goelz, J.C.G.; Carlson, D.W.

Sawtooth oak (Quercus acutissima Carruth) was direct seeded at two locations, one with a poorly drained clay soil and the other with a well-drained silty clay loam. For comparison, Nuttall oak (Q. nuttallii Palmer) was direct seeded on the poorly drained clay soil. On the well-drained silty clay loam, sawtooth oak was 18 ft taller and 2.4 inches larger in d.b.h. at age 22 than on the poorly drained clay soil. On the clay, sawtooth oak grew faster than Nuttall oak, but survival was lower. Almost all sawtooth oaks were producing acorns on both sites; however, no developing acorns weremore » found on the Nuttall oaks. Sawtooth oak is a viable alternative for planting on a wide range of Mississippi Delta forest types. Because sawtooth oak has a poorer form than Nuttal oak, its primary use is as a source of wildlife food. Sawtooth oak could be included in plantings with the multiple objectives of timber production and wildlife use because it grows well and could potentially be used for pulpwood.« less

A Real-Time Image Acquisition And Processing System For A RISC-Based Microcomputer

NASA Astrophysics Data System (ADS)

Luckman, Adrian J.; Allinson, Nigel M.

1989-03-01

A low cost image acquisition and processing system has been developed for the Acorn Archimedes microcomputer. Using a Reduced Instruction Set Computer (RISC) architecture, the ARM (Acorn Risc Machine) processor provides instruction speeds suitable for image processing applications. The associated improvement in data transfer rate has allowed real-time video image acquisition without the need for frame-store memory external to the microcomputer. The system is comprised of real-time video digitising hardware which interfaces directly to the Archimedes memory, and software to provide an integrated image acquisition and processing environment. The hardware can digitise a video signal at up to 640 samples per video line with programmable parameters such as sampling rate and gain. Software support includes a work environment for image capture and processing with pixel, neighbourhood and global operators. A friendly user interface is provided with the help of the Archimedes Operating System WIMP (Windows, Icons, Mouse and Pointer) Manager. Windows provide a convenient way of handling images on the screen and program control is directed mostly by pop-up menus.

Microwave Dispersion and Absorption in Tissues: Molecular Mechanisms

DTIC Science & Technology

1987-12-10

transverse and rotating frame NMR relaxation in barnacle muscle. H. A. Resing, A. N. Garroway , and K. R. Foster. Presented at the American Chemical Society...indicated by nuclear magnetic resonance studies. (Technical Comment) H. A. Resing, K. R. Foster and A. N. Garroway . Science, Vol: 198, Page 1180, 1977

Estimating mast production: an evaluation of visual surveys and comparison with seed traps using white oaks

Treesearch

Roger W. Perry; Ronald E. Thill

1999-01-01

Perry and Thill compared five types of visual mast surveyed with seed trap data from 105 white oaks (Quercus alba L.) during 1996-1997 in the Ouachita Mountains of Arkansas. They also evaluated these visual survey methods for their usefulness in detecting differences in acorn density among areas. Indices derived from all five methods were highly...

Nature's Palette

ERIC Educational Resources Information Center

McBride, Brooke B.; Brewer, Carol A.

2010-01-01

Flower petals, acorn hats, exoskeletons of beetles, and lichens are just a few of the objects students may find in a surprising array of vivid colors. These tiny examples from nature's palette can be discovered in a school yard, a park, or even along the edges of a paved sidewalk...it simply takes careful observation! This article describes a…

Insects affecting establishment of northern red oak seedlings in central Pennsylvania

Treesearch

J. Galford; L.R. Auchmoody; H.C. Smith; R.S. Walters

1991-01-01

Studies to evaluate the impact of insects on the establishment of advance oak regeneration in Pennsylvania were initiated in 1989. The populations and species of insects feeding on germinating acorns and new seedlings, their activity periods, and the damage caused by these insects were studied in relation to overstory-density (40, 60, and 100 percent relative density)...

Intraspecific Phenotypic Variation and Ecological Genetics of Blue Oak (Quercus douglasii Hook. & Am.)

Treesearch

Kevin J. Rice; Doria R. Gordon; Jeanine L. Hardison; Jeffrey M. Welker

1991-01-01

A field experiment was conducted to examine the effects of soil water availability on blue oak (Quercus douglasii) seedling establishment. Acorns were planted either into cleared plots of 0, 10, 20, or 40 cm diameter. The cleared plots were located in two grazed and one ungrazed site. Half of the plots received drip irrigation in a split plot design...

The oak woodland bird conservation plan: a strategy for protecting and managing oak woodland habitats and associated birds in California

Treesearch

Steve Zack; Mary K. Chase; Geoffrey R. Geupel

2002-01-01

Over 330 species of birds, mammals, reptiles, and amphibians depend on oak woodlands in California at some stage in their life cycle. California oak woodlands may rank among the top three habitat types in North America for bird richness. Oak woodlands are able to sustain such abundant wildlife primarily because they produce acorns, a high quality and frequently copious...

The Oak Woodland Bird Conservation Plan: A Strategy for Protecting and Managing Oak Woodland Habitats and Associated Birds in California

Treesearch

Steve Zack; Mary K. Chase; Geoffrey R. Geupel; Diana Stralberg

2005-01-01

Over 330 species of birds, mammals, reptiles, and amphibians depend on oak woodlands in California (fig. 1) at some stage in their life cycle (Barrett 1980; Verner 1980; Block and Morrison 1998). These woodlands are able to sustain such abundant wildlife primarily because they produce acorns, a high quality and frequently copious food supply. The birds of California?s...

Comparing natural and artificial methods for establishing pin oak advance reproduction in bottomland forests managed as greentree reservoirs

Treesearch

Nicholas Krekeler; John M. Kabrick; Daniel C. Dey; Michael Wallendorf

2006-01-01

Abstract—In greentree reservoirs within the Mingo Basin in southeastern Missouri, we compared the survival and growth of underplanted pin oak (Quercus palustris Muenchh.) acorns, bareroot seedlings, and RPM® container seedlings in plots that were thinned with and without ground flora control. After one growing season, we found that RPM® container...

Oak Regeneration Using the Two-Age System

Treesearch

Jeffrey W. Stringer

2002-01-01

The two studies presented in this paper were completed in southeastern Kentucky and were designed to evaluate acorn production and development of advanced white oak reproduction from fully released white oak (Quercus alba) trees typical of reserve trees in the two age system. Twelve 2 acre 60- to 90-year-old white oak dominated stands were...

Regenerating oaks in Missouri's bottomlands

Treesearch

Dan Dey; John Kabrick

2004-01-01

Bottomland oaks are valuable timber species that are also important for wildlife, but regenerating them is about as easy as training blackbirds to plant acorns. Missouri once had an estimated 5 million acres of wetlands, much of which were bottomland forests that included some oak. Today, less than 15 percent of those historical wetlands remain in the state. Many...

Fire in upper Midwestern oak forest ecosystems: an oak forest restoration and management handbook

Treesearch

Lee E. Frelich; Peter B. Reich; David W. Peterson

2015-01-01

We reviewed the literature to synthesize what is known about the use of fire to maintain and restore oak forests, woodlands, and savannas of the upper Midwestern United States, with emphasis on Minnesota, Wisconsin, and Michigan. Included are (1) known physical and ecological effects of fire on oaks from acorn through seedling, established sapling, and mature stages of...

Microsatellite markers for northern red oak (Fagaceae: Quercus rubra)

Treesearch

Preston R. Aldrich; Charles H. Michler; Weilin Sun; Jeanne Romero-Severson

2002-01-01

We provide primer sequences for 14 (GA)n microsatellite loci developed from northern red oak, an important timber species. We screened loci using two sets of samples. A parent-offspring set included DNA from seven acorns collected from one mother tree along with maternal DNA, to determine that all progeny carried a maternal allele at each locus....

Soil Water Effects on Blue Oak Seedling Establishment

Treesearch

Doria R. Gordon; Kevin J. Rice; Jeffrey M. Welker

1991-01-01

A field experiment was conducted to examine the effects of soil water availability on blue oak (Quercus douglasii) seedling establishment. Acorns were planted either into cleared plots of 0, 10, 20, or 40 cm diameter. The cleared plots were located in two grazed and one ungrazed site. Half of the plots received drip irrigation in a split plot design...

Oak Symposium Proceedings

Treesearch

Northeastern Forest Experiment Station

1971-01-01

As "tall oaks from little acorns grow", the germ of an idea blossomed into this symposium on the five upland oaks. Called simply the "Oak Symposium", that's what it's all about - a meeting to bring together a summation of the advances made on the silviculture, management, and utilization of the upland oaks. Part of this process is the...

Keeping FCS Relevant with Technology

ERIC Educational Resources Information Center

Hays, Annette

2007-01-01

Acorn School campus is located in the shadow of Rich Mountain, near Mena, Arizona. In fall 2006, the school enrollment (K-12) was 476 students, with 76% eligible for free or reduced-cost meals. Its one-teacher family and consumer services (FCS) department offers two programs of study: Family and Consumer Sciences Education and Food Production…

Protecting red oak seedlings with tree shelters in northwestern Pennsylvania

Treesearch

Russell S. Walters; Russell S. Walters

1993-01-01

Examines the growth and survival of planted and natural red oak seedlings and seedlings from planted acorns within translucent tan tree shelters, fences, and unprotected controls under a shelterwood seed-cut stand. Seedlings planted within tree shelters and fences were inside tree shelters. Natural seedlings grew very little and their height inside and outside of tree...

Quercus lobata seedlings and conspecific neighbors: Competitors or allies?

Treesearch

Claudia Tyler; Shelly Cole Moritz

2015-01-01

In conducting oak restoration, it is common to plant at least two acorns per location to increase the probability that at least one will germinate and produce a seedling. If both seedlings successfully establish, one is generally removed to reduce possible competition. To test the assumption that the near neighbors are competing, we examined several cohorts of valley...

Recruitment dynamics in complex life cycles. [of organisms living in marine rocky zone

NASA Technical Reports Server (NTRS)

Roughgarden, Jonathan; Possingham, Hugh; Gaines, Steven

1988-01-01

Factors affecting marine population fluctuations are discussed with particular attention given to a common barnacle species of the Pacific coast of North America. It is shown how models combining larval circulation with adult interactions can potentially forecast population fluctuations. These findings demonstrate how processes in different ecological habitats are coupled.

Evaluation of oak stump sprouting in the Missouri Ozarks ten years after harvest

Treesearch

Randy G. Jensen; Daniel C. Dey

2008-01-01

Managers in Missouri often want to manage forests to retain oak in the future. Oaks are valuable for timber and many wildlife species depend on acorns. Large advance reproduction and stump sprouts are the most competitive sources of regeneration. It is well known that oak stump sprouts contribute to future stands in even-age clearcuts in the Missouri Ozarks, but there...

Gypsy moth effects on mast production

Treesearch

Kurt W. Gottschalk

1990-01-01

Gypsy moth outbreaks can have drastic effects on many forest resources and uses. Because the gypsy moth prefers oak foliage, oak stands are the most susceptible to defoliation and resultant damage. The value of oak mast for many wildlife species is high. The high carbohydrate content of acorns provides the energy necessary for winter survival. Loss of mast crops due to...

People and oaks

Treesearch

Paul F. Starrs

2015-01-01

While technical knowledge of oaks, acorns, habitat, wildlife, and woodland environments is evolving and a sought-after field of study, there are profound linkages, at once humanistic and artistic, where it comes to people and oaks. Looking at six distinct facets of humans and oak woodlands, this essay suggests that the bonds of people to place can be mediated by the...

Prehistory of the Little Blue River Valley, Western Missouri: Archaeological Investigations at Blue Springs Lake.

DTIC Science & Technology

1989-01-01

amaranths, chenopods and purslane , along with mast resources, such as acorns and hickory nuts. The restricted periods of availability of these plant...Polygonum pensylvanicum (Pensylvania smartweed) fall Portulaca mundula ( purslane ) fall Portulaca oleracea (common purslane ) fall Rorippa palustris...and Bright 1968) and the oxygen-isotope ratios of mollusk shells (Stuiver 1970), which all indicate increased salinity at the time of maximum prairie

Deer damage in central hardwoods: a potential problem

Treesearch

Nancy G. Tilghman; David A. Marquis

1989-01-01

A major part of the diet of white-tailed deer consists of herbaceous plants, acorns, other tree fruits, and the twigs of trees and shrubs. Deer browsing on young tree seedlings can influence the success of regeneration in forest stands. Excessive deer browsing is not a major problem in the central hardwood forest type, except in parts of Pennsylvania and, to a lesser...

Establishing a range-wide provenance test in valley oak (Quercus lobata Née) at two California sites

Treesearch

Annette Delfino-Mix; Jessica W. Wright; Paul F. Gugger; Christina Liang; Victoria L. Sork

2015-01-01

We present the methods used to establish a provenance test in valley oak, Quercus lobata. Nearly 11,000 acorns were planted and 88 percent of those germinated. The resulting seedlings were measured after 1 and 2 years of growth, and were outplanted in the field in the winter of 2014-2015. This test represents a long-term resource for both research...

Survey of Generation and Management of Explosive-Laden Spent Carbon

DTIC Science & Technology

1992-11-25

aind Hazardo.t- I Materia ls A cenc ’v (L’SATH-o A ") 6C. ADDRESS (1ty. State•, and ZIPCod*) 7b. ADDRESS (Oty, State. end ZIP Cock) Acorn Park ATTN...hereunder will not be provided to the Cooperator. Any statement the Bureau desires to provide regarding the status of funds or materials shall be deemed prima

Direct Seeding of Southern Oaks - A Progress Report

Treesearch

Robert L. Johnson; Roger M. Krinard

1987-01-01

Since 1981 over 4,000 acres of publicly and privately owned land, mostly in flood plains, have been direct seeded with acorns. Most seedings have been in abandoned farm land, the rest in forest openings created by commercial tree harvest. Cost data associated with a few of the production trials are presented in this paper. Also included are discussions of production...

Performance of northern red oak seedlings across a pH gradient

Treesearch

Anthony S. Davis; Douglass F. Jacobs

2005-01-01

Northern red oak (Quercus rubra L.) seedlings were grown from acorns in 4-gallon containers in a greenhouse. Growing medium was amended to a pH of 3.50, 4.25, 5.00, and 5.75 using tri-weekly applications of aluminum sulfate. In addition, seedlings were subjected to either: (1) addition of a 16- to 18-month controlled release fertilizer (CRF), (2)...

The Varieties of Religious Experience: Baptized Indians at Mission San Francisco de Asis, 1776-1821

ERIC Educational Resources Information Center

Newell, Quincy D.

2008-01-01

Paseos, which are defined as trips away from the mission authorized by the Franciscan priests, were common among Indians baptized at Mission San Francisco during the period between 1700s to 1800s. Indians went on these journeys in order to harvest acorns and other wild foods, to hunt and fish, and to visit friends and family outside the mission.…

Rehabilitation of an oak planting project on cleared rangeland using treeshelters and grazing: a ten-year saga

Treesearch

Jerry Tecklin; Michael Connor; Douglas D. McCreary

2002-01-01

On a 2-hectare site at the Sierra Foothill Research and Extension Center near Marysville, California, 1,440 blue oaks (Quercus douglasii) were planted during 1990-91 in an attempt to re-vegetate an oak woodland that had been almost totally cleared for cattle grazing during the mid-1960s. This initial planting of acorns, 4-month old seedlings, and 1-...

Feeding by larvae of intertidal invertebrates: assessing their position in pelagic food webs.

PubMed

Vargas, Cristian A; Manríquez, Patricio H; Navarrete, Sergio A

2006-02-01

One of the leading determinants of the structure and dynamics of marine populations is the rate of arrival of new individuals to local sites. While physical transport processes play major roles in delivering larvae to the shore, these processes become most important after larvae have survived the perils of life in the plankton, where they usually suffer great mortality. The lack of information regarding larval feeding makes it difficult to assess the effects of food supply on larval survival, or the role larvae may play in nearshore food webs. Here, we examine the spectrum of food sizes and food types consumed by the larvae of two intertidal barnacle species and of the predatory gastropod Concholepas concholepas. We conducted replicated experiments in which larvae were exposed to the food size spectrum (phytoplankton, microprotozoan and autotrophic picoplankton) found in nearshore waters in central Chile. Results show that barnacle nauplii and gastropod veligers are omnivorous grazers, incorporating significant fractions of heterotrophs in their diets. In accordance with their feeding mechanisms and body size, barnacle nauplii were able to feed on autotrophic picoplankton (<5 microm) and did not consume the largest phytoplankton cells, which made the bulk of phytoplankton biomass in spring-summer blooms. Balanoid nauplii exhibited higher ingestion rates than the smaller-bodied chthamaloid larvae. Newly hatched C. concholepas larvae also consumed picoplankton cells, while competent larvae of this species ingested mostly the largest phytoplankton cells and heterotrophic protozoans. Results suggest that persistent changes in the structure of pelagic food webs can have important effects on the species-specific food availability for invertebrate larvae, which can result in large-scale differences in recruitment rates of a given species, and in the relative recruitment success of the different species that make up benthic communities.

[Feeding changes for three Sphoeroides species (Tetraodontiformes: Tetraodontidae) after Isidore hurricane impact in Carbonera Inlet, Southeastern Gulf of Mexico].

PubMed

Palacios-Sánchez, Sonia Eugenia; Vega-Cendejas, María Eugenia

2010-12-01

The coexistence of ecologically similar species may occur because of resources distribution, such as prey and habitat type and segregation time, that minimizes the interspecific competition. The changes brought about by Hurricane Isidore in the distribution of food resources by three coexisting fish species of the family Tetraodontidae (Sphoeroides nephelus, S. spengleri and S testudineus), were analyzed at the Carbonera Inlet. Sphoeroides spp. based their food on benthic organisms; principally, they consume mussels (Brachidontes sp.), barnacles (Balanus sp.) and gastropods (Crepidula sp). Before hurricane impact, the three species share the available food resources in different proportions (bivalves, gastropods, barnacles and decapods), according to different strategies that enabled them to coexist and reduce interspecific competition. After the impact, the abundance of available prey decreased and the interespecific competition for food increased, leading to S. testudines and S. nephelus change their trophic spectrum (xiphosurans, amphipods, isopods and detritus) and displacing S. splengleri of the inlet. The distribution of food resources was conditioned by the abundance and diversity of prey, as well as the adaptive response of each species.

Abundance, seasonal patterns and diet of the non-native jellyfish Blackfordia virginica in a Portuguese estuary

NASA Astrophysics Data System (ADS)

Marques, F.; Chainho, P.; Costa, J. L.; Domingos, I.; Angélico, M. M.

2015-12-01

Blackfordia virginica, a non-indigenous hydrozoan introduced in many systems around the world, has been observed in the Mira estuary, southwest of Portugal, since 1984. Monthly sampling (January 2013-January 2014) at a fixed location with high abundance of the medusae confirmed the occurrence of a seasonal cycle associated with temperature and photoperiod. The beginning of the medusa cycle occurred in May immediately after the spring zooplankton bloom during April. Examination of the gut contents of B. virginica medusae revealed that copepods, the most abundant group in the zooplankton community, were highly predated. Barnacle nauplii, decapod crustacean larvae and anchovy eggs were also identified in the guts. The medusae showed positive selection for copepods, and negative selection for barnacle nauplii, decapod crustacean larvae and anchovy eggs. The mortality rate of copepods (used as a model prey group) induced by medusae predation was estimated and showed the potential impact of this species in the ecosystem, ranging between 2.34 d-1 and 0.02 d-1, with a minimum copepod half-life of 0.30 days.

Polysulfone and polyacrylate-based zwitterionic coatings for the prevention and easy removal of marine biofouling

DOE PAGES

Hibbs, Michael R.; Hernandez-Sanchez, Bernadette A.; Daniels, Justin; ...

2015-09-07

A series of polysulfone and polyacrylate-based zwitterionic coatings were prepared on epoxy-primed aluminum substrata and characterized for their antifouling (AF) and fouling-release (FR) properties towards marine bacteria, microalgae and barnacles. The zwitterionic polymer coatings provided minimal resistance against bacterial biofilm retention and microalgal cell attachment, but facilitated good removal of attached microbial biomass by exposure to water-jet apparatus generated hydrodynamic shearing forces. Increasing the ion content of the coatings improved the AF properties, but required a stronger adhesive bond to the epoxy-primed aluminum substratum to prevent coating swelling and dissolution. Grafted poly(sulfobetaine) (gpSBMA), the most promising zwitterionic coating identified frommore » microfouling evaluations, enabled the removal of four out of five barnacles reattached to its surface without incurring damage to their baseplates. As a result, this significant result indicated that gpSBMA relied predominately on its surface chemistry for its FR properties since it was very thin (~1–2 µm) relative to commercial coating standards (>200 µm).« less

Fragon: rapid high-resolution structure determination from ideal protein fragments.

PubMed

Jenkins, Huw T

2018-03-01

Correctly positioning ideal protein fragments by molecular replacement presents an attractive method for obtaining preliminary phases when no template structure for molecular replacement is available. This has been exploited in several existing pipelines. This paper presents a new pipeline, named Fragon, in which fragments (ideal α-helices or β-strands) are placed using Phaser and the phases calculated from these coordinates are then improved by the density-modification methods provided by ACORN. The reliable scoring algorithm provided by ACORN identifies success. In these cases, the resulting phases are usually of sufficient quality to enable automated model building of the entire structure. Fragon was evaluated against two test sets comprising mixed α/β folds and all-β folds at resolutions between 1.0 and 1.7 Å. Success rates of 61% for the mixed α/β test set and 30% for the all-β test set were achieved. In almost 70% of successful runs, fragment placement and density modification took less than 30 min on relatively modest four-core desktop computers. In all successful runs the best set of phases enabled automated model building with ARP/wARP to complete the structure.

Anti-Icing Chitin Coating System Development

DTIC Science & Technology

1990-10-30

medium. Second, antifouling paints must inhibit barnacles, algae and fungi destruction. Current paints contain TBT , cuprous oxide, mercury, water-soluble... TBT ) copolymer (Intersmooth SPC) erodes slowly but requires expensive hull preparation. Courtauld, Jotun, Kansai Paint and Chugoku Marine Paint...manufacturer TBT -free ablative paints. These paints, however, contain cuprous oxide, mercury, water-soluble acrylic organotin polymer or polysiloxane

Final Asbestos Report (AREE 65) Base Realignment and Closure Environmental Evaluation (BRAC EE), Part 2, Fort Devens, Massachusetts

DTIC Science & Technology

1995-05-01

Submitted to U.S. Army Environmental Center (USAEC) Aberden Proving Ground , Maryland Revision 1 May 1995 Arthur D. Littl., Inc. Acorn Park Camnbridge...ADORESS(ES) 10. SPONSORINGIMONITORING" ~AGENCY REPORT NUMBER U.S. Army Environmental Center Aberdeen Proving Ground , Maryland 11. SUPPLEMENTARY NOTES...May 1995 proves the material to be non-ACM. OSHA has classified these materials as "Presumed Asbestos-Containing Materials (PACM)." Therefore, SACBM

Cultural Resources Survey of Fourteen Mississippi River Levee and Revetment Items.

DTIC Science & Technology

1982-04-14

floodplain forest of hackberry, cottonwood, pecan , bitter pecan , water oak, ash, elm and boxelder is characteristic. The understory in these areas is...contained the greatest diversity of resources such as acorns from live oak (Quercus virginiana) and willow oak (Quercus phellos), nuts from bitter pecan ...Carya aquatica) and pecan (Carya illinoensis), fruits from persimmon (Diospyros virginiana) and mulberry (Morus rubra) and edible roots from

Autumn predation of northern red oak seed crops

Treesearch

Kim C. Steiner

1995-01-01

Production and autumn predation of northern red oak acorns was measured over four years in five Pennsylvania stands dominated by this species. Mean annual production was 41,779/acre, of which an average of 7.9% was destroyed by insects or decay following insect attack, and an average of 38.6% was destroyed or removed by vertebrates. White-tailed deer appeared to be the...

Conceptual understandings of biology in pre-service science educators and undergraduate biology students at Colorado institutions of higher education

NASA Astrophysics Data System (ADS)

Smith, Trenton John

Pre-service secondary science individuals, future middle or high school instructors training to become teachers, along with both Honors and general first year undergraduate biology students were investigated to determine how they reason about and understand two core topics in Biology: matter and energy flow through biological systems and evolution by natural selection. Diagnostic Question Clusters were used to assess student understanding of the processes by which matter and energy flow through biological systems over spatial scales, from the atomic-molecular to ecosystem levels. Key concepts and identified misconceptions were examined over topics of evolution by natural selection using the multiple-choice Concept Inventory of Natural Selection (CINS) and open-response Assessing COntextual Reasoning about Natural Selection (ACORNS). Pre-service teachers used more scientifically based reasoning than the undergraduate students over the topics of matter and energy flow. The Honors students used more scientific and less improper informal reasoning than the general undergraduates over matter and energy flow. Honors students performed best on both the CINS and ACORNS items over natural selection, while the general undergraduates scored the lowest on the CINS, and the pre-service instructors scored lowest on the ACORNS. Overall, there remain a large proportion of students not consistently using scientific reasoning about these two important concepts, even in future secondary science teachers. My findings are similar to those of other published studies using the same assessments. In general, very few biology students at the college level use scientific reasoning that exhibits deep conceptual understanding. A reason for this could be that instructors fail to recognize deficiencies in student reasoning; they assume their students use principle-based reasoning. Another reason could be that principle-based reasoning is very difficult and our teaching approaches in college

Surface-Piercing Activities of the Humpback Whale, Megaptera, Related to Parasites and Mechanics}

NASA Astrophysics Data System (ADS)

Galvin, C.

2006-12-01

Humpback whales leap out of the water (breach), strike the water surface with their long fins (flipper), strike the water surface with their tail (lobtail), and hold motionless in a vertical position with their heads above water (spyhop). These four surface-piercing activities were known to early whalers, but their explanations remain uncertain. A whale breaches by swimming from depth toward the water surface at an oblique angle, propelling himself into the air at an angle to the water's surface (0 to 70 degrees), rotating about his long axis, and landing on his back, belly up to the sky. Rotation requires applying angular momentum to the whale's trunk, which photographs suggest comes from flinging out the flipper on the side rotating upward, and keeping the downward-rotating flipper closer to the trunk. The humpback has unusually long flippers (long moment arms) up to 30 percent of trunk length. Its generic name, Megaptera, can translate as `long flipper'. Continued use of one flipper as the moment arm raises the possibility of right-handed or left-handed whales, but Whitehead's (1985) data do not support that result. Parasites as a cause of breaching is a hypothesis at least as old as Beale (1839), but in the last half of the 20th century, breaching, flippering, and lobtailing came to be understood as social activities of whales. Whitehead's work in the 1980s provides much data on humpback activities, as well as a prevailing social interpretation of the data. External parasites (loosely defined) include whale lice (fingernail-sized crablike animals) and barnacles (both fixed shell and flexible goosenecked species). Thousands of these animals may inhabit a single whale. Whale lice populate crevices of the jaws and eyes, the pleats in the throat pouch under the jaw, and shelter at fixed barnacles. Fixed barnacles thrive on exposed bumps on the whale's head and flippers. Gooseneck barnacles appear in photos attached to trailing edges of fins and tail. Some parasites

Photosynthesis and Biomass Allocation in Oak Seedlings Grown Under Shade

Treesearch

Shi-Jean S. Sung; Paul P. Kormanik; Stanley J. Zarnoch

1998-01-01

Abstract-Northern red oak (Quercus rubra L.) (NRO) and white oak (Q. alba L.) (WO) acorns were sown into wooden plots and grown under 30 percent shade screen (30 percent S) or 70 percent shade screen (70 percent S). Seedlings grown under full sun were the controls (C). At the end of the first year, the 30 percent S NRO had 30 percent greater seedling dry weight (DW...

Determining seed moisture in Quercus

Treesearch

F. T. Bonner

1974-01-01

The air-oven method with drying times 7 to 8 hours shorter than those now prescribed in the ISTA rules proved adequate for determining moisture contents in acorns of several North American oaks. Schedules of 8 hours at 105°C for Quercus muehlenbergii and 9 hours at 105°C for Q.shumardii and Q.nigra gave moisture contents within three percentage points of those obtained...

Merced County Streams Project, Burns Reservoir, California Intensive Cultural Resources Survey.

DTIC Science & Technology

1981-01-01

Larry McKee, and Melinda Peak; and to the technicians: Barry Boyer, Herb Dallas, Hannah Gibbs, Stuart Guedon, Sherri Gust, Les Harville, Paul...Subsistence was based on the acorn and supplemented by gathering of seeds, berries, greens, nuts, and edible roots. Fish, game, and small mammals...the continent to witness. Large troops of wild horses, many deer, antelope, and coyotes were-constantly on view (Keyes 1884:234). The horses had been

Grazing effects of the periwinkle Echinolittorina peruviana at a central Peruvian high rocky intertidal

NASA Astrophysics Data System (ADS)

Hidalgo, Fernando J.; Firstater, Fausto N.; Fanjul, Eugenia; Bazterrica, M. Cielo; Lomovasky, Betina J.; Tarazona, Juan; Iribarne, Oscar O.

2008-03-01

Echinolittorina peruviana is the most common gastropod in the high intertidal zone of Peru, representing more than 80% of the individuals present at that zone. Experimental removal of snails was used to evaluate their effects on (a) abundance of epilithic biofilm, (b) barnacle recruitment, and (c) abundance of macroalgae under “normal” conditions of the El Niño Southern Oscillation (ENSO). Experiments were carried out from October 2005 to April 2007 at two intertidal levels of a semi-protected rocky shore of central Peru. Results demonstrated that E. peruviana is able to control biofilm abundance and barnacle recruitment at both heights investigated, with marked effects in the lower zone. Erect macroalgae ( Ulva spp. and Gelidium spp.) were less affected by grazing; but negative effects were observed on macroalgal crusts. Season and physical stress seem to play a more important role in the abundance of macroalgae in the high intertidal. Our results are similar to those reported elsewhere for high shore littorinids and represent baseline data to understand how the role of intertidal consumers will vary under the cold (La Niña) and warm (El Niño) phases of ENSO on these shores.

Chemometric analysis of minerals in gluten-free products.

PubMed

Gliszczyńska-Świgło, Anna; Klimczak, Inga; Rybicka, Iga

2018-06-01

Numerous studies indicate mineral deficiencies in people on a gluten-free (GF) diet. These deficiencies may indicate that GF products are a less valuable source of minerals than gluten-containing products. In the study, the nutritional quality of 50 GF products is discussed taking into account the nutritional requirements for minerals expressed as percentage of recommended daily allowance (%RDA) or percentage of adequate intake (%AI) for a model celiac patient. Elements analyzed were calcium, potassium, magnesium, sodium, copper, iron, manganese, and zinc. Analysis of %RDA or %AI was performed using principal component analysis (PCA) and hierarchical cluster analysis (HCA). Using PCA, the differentiation between products based on rice, corn, potato, GF wheat starch and based on buckwheat, chickpea, millet, oats, amaranth, teff, quinoa, chestnut, and acorn was possible. In the HCA, four clusters were created. The main criterion determining the adherence of the sample to the cluster was the content of all minerals included to HCA (K, Mg, Cu, Fe, Mn); however, only the Mn content differentiated four formed groups. GF products made of buckwheat, chickpea, millet, oats, amaranth, teff, quinoa, chestnut, and acorn are better source of minerals than based on other GF raw materials, what was confirmed by PCA and HCA. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Interspecific differences in tannin intakes of forest-dwelling rodents in the wild revealed by a new method using fecal proline content.

PubMed

Shimada, Takuya; Nishii, Eriko; Saitoh, Takashi

2011-12-01

Mammalian herbivores adopt various countermeasures against dietary tannins, which are among the most widespread plant secondary metabolites. The large Japanese wood mouse Apodemus speciosus produces proline-rich salivary tannin-binding proteins in response to tannins. Proline-rich proteins (PRPs) react with tannins to form stable complexes that are excreted in the feces. Here, we developed a new method for estimating the tannin intake of free-living small rodents, by measuring fecal proline content, and applied the method to a field investigation. A feeding experiment with artificial diets containing various levels of tannic acid revealed that fecal proline content was clearly related to dietary tannin content in three species (A. speciosus, Apodemus argenteus, and Myodes rufocanus). We then used fecal proline content to estimate the tannin intakes of these three forest-dwelling species in a forest in Hokkaido. In the autumn, estimated tannin intakes increased significantly in the Apodemus species, but not in M. rufocanus. We speculated that an increase in tannin intake during autumn may result from consumption of tannin-rich acorns. This hypothesis was consistent with population fluctuation patterns of the three species, which were well-synchronized with acorn abundance for the Apodemus species but not for M. rufocanus.

Regional variations in mortality rates in England and Wales: an analysis using multi-level modelling.

PubMed

Langford, I H; Bentham, G

1996-03-01

Mortality rates in England and Wales display a persistent regional pattern indicating generally poorer health in the North and West. Some of this is simply a reflection of regional differences in the extent of social deprivation which is known to exert a profound influence on health. Part of the pattern may also be the result of regional differences in urbanization which also affect mortality rates. However, there may be important regional differences over and above these compositional effects. This study attempts to establish the magnitude of such independent regional differences in mortality rates by using the techniques of multi-level modelling. Standardized mortality rates (SMRs) for males and females under 65 for 1989-91 in local authority districts are grouped into categories using the ACORN classification scheme. The Townsend Index is included as a measure of social deprivation. Using a cross-classified multi-level model, it is shown that region accounts for approximately four times more variation in SMRs than is explained by the ACORN classification. Analysis of diagnostic residuals show a clear North-South divide in excess mortality when both regional and socio-economic classification of districts are modelled simultaneously, a possibility allowed for by the use of a multi-level model.

Engineering of Nanoscale Antifouling and Hydrophobic Surfaces on Naval Structural Steel HY-80 by Anodizing

DTIC Science & Technology

2015-06-01

examination of the morphologies of the nanoporous structures and the evaluation of the anodization parameters such as anodization potential, time... sponges , anemones, tunicates, and hydroids, whilst hard fouling comprises invertebrates such as barnacles, mussels, and tubeworms. The specific...of metals by making them more stable and highly resistant, but also to modify the surface by giving it a desired morphology . Ferrous alloys such as

Silicone Foul Release Coatings: Effect of the Interaction of Oil and Coating Functionalities on the Magnitude of Macrofouling Attachment Strengths

DTIC Science & Technology

2003-01-01

Hawaii) is described. The response of tubeworms (Hydroides elegans, Hydroides dianthus ), oysters (Ostrea sp., Crassostrea sp.) and barnacles (Balanus...8 and Hydroides dianthus ) and oysters (Ostrea sp. and Crassostrea sp.) to the silicone coatings were measured using ASTM D 5618-94 (1994), in which...Oyster (Crassostrea sp.) and tubeworm (H. dianthus ) attachment strengths at the Indian River Lagoon site Linear regression analyses of the adhesion

Protein Aggregation Formed by Recombinant cp19k Homologue of Balanus albicostatus Combined with an 18 kDa N-Terminus Encoded by pET-32a(+) Plasmid Having Adhesion Strength Comparable to Several Commercial Glues

PubMed Central

Liang, Chao; Li, Yunqiu; Liu, Zhiming; Wu, Wenjian; Hu, Biru

2015-01-01

The barnacle is well known for its tenacious and permanent attachment to a wide variety of underwater substrates, which is accomplished by synthesizing, secreting and curing a mixture of adhesive proteins termed “barnacle cement”. In order to evaluate interfacial adhesion abilities of barnacle cement proteins, the cp19k homologous gene in Balanus albicostatus (Balcp19k) was cloned and expressed in Escherichia coli. Here, we report an intriguing discovery of a gel-like super adhesive aggregation produced by Trx-Balcp19k, a recombinant Balcp19k fusion protein. The Trx-Balcp19k consists of an 18 kDa fragment at the N-terminus, which is encoded by pET-32a(+) plasmid and mainly comprised of a thioredoxin (Trx) tag, and Balcp19k at the C-terminus. The sticky aggregation was designated as “Trx-Balcp19k gel”, and the bulk adhesion strength, biochemical composition, as well as formation conditions were all carefully investigated. The Trx-Balcp19k gel exhibited strong adhesion strength of 2.10 ± 0.67 MPa, which was approximately fifty folds higher than that of the disaggregated Trx-Balcp19k (40 ± 8 kPa) and rivaled those of commercial polyvinyl acetate (PVA) craft glue (Mont Marte, Australia) and UHU glue (UHU GmbH & Co. KG, Germany). Lipids were absent from the Trx-Balcp19k gel and only a trace amount of carbohydrates was detected. We postulate that the electrostatic interactions play a key role in the formation of Trx-Balcp19k gel, by mediating self-aggregation of Trx-Balcp19k based on its asymmetric distribution pattern of charged amino acids. Taken together, we believe that our discovery not only presents a promising biological adhesive with potential applications in both biomedical and technical fields, but also provides valuable paradigms for molecular design of bio-inspired peptide- or protein-based materials. PMID:26317205

Assessing the chronic toxicity of nickel to a tropical marine gastropod and two crustaceans.

PubMed

Gissi, Francesca; Stauber, Jenny L; Binet, Monique T; Trenfield, Melanie A; Van Dam, Joost W; Jolley, Dianne F

2018-09-15

The mining and processing of nickel ores from tropical regions contributes 40% of the global supply. The potential impact of these activities on tropical marine ecosystems is poorly understood. Due to the lack of ecotoxicity data for tropical marine species, there is currently no available water quality guideline value for nickel that is specific to tropical species. In this study, we investigated the toxicity of nickel to three tropical marine invertebrates, the gastropod Nassarius dorsatus, the barnacle Amphibalanus amphitrite, and the copepod Acartia sinjiensis. All toxicity tests used chronic endpoints, namely larval growth, metamorphosis (transition from nauplii to cyprid larvae) and larval development for the snail, barnacle and copepod respectively. Toxicity tests were carried out under environmentally relevant conditions (i.e. 27-30ᵒC, salinity 34-36‰, pH 8.1-8.4). Copper was also tested for quality assurance purposes and to allow for comparisons with previous studies. The copepod was the most sensitive species to nickel, with development inhibited by 10% (EC10) at 5.5 (5.0-6.0) µg Ni/L (95% confidence limits (CL)). Based on EC10 values, the gastropod and barnacle showed similar sensitivities to nickel with growth and metamorphosis inhibited by 10% at 64 (37-91) µg Ni/L and 67 (53-80) µg Ni/L, respectively. Based on existing data available in the literature, the copepod A. sinjiensis is so far the most sensitive tropical marine species to nickel. This study has provided high quality data which will contribute to the development of a water quality guideline value for nickel in tropical marine waters. A species sensitivity distribution of chronic nickel toxicity used the data generated in this paper supplemented by available literature data, comprising 12 species representing 6 taxonomic groups. A 5% hazard concentration (HC5) was determined as 8.2 µg/L Ni. Crown Copyright © 2018. Published by Elsevier Inc. All rights reserved.

Geotechnical and Geoacoustic Properties of Sediments Off South Florida: Boca Raton, Indian River Beach, Lower Tampa Bay, and the Lower Florida Keys

DTIC Science & Technology

1997-06-24

foraminifers, sea urchin spines, barnacles, spiny oysters, worm shells, bivalves, coral fragments, and few quartz grains. The sediments are composed of...photographing a diver’s compass on the sea bottom as the first photograph of a photographic transect along a tape measure previously laid down on the sea ...measurements for distortion caused by refraction in sea water and lens aberrations. Use of the stereocomparator allows high frequency sampling of bottom

Macrofouling control in nuclear power plants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ekis, E.W. Jr.; Keoplin-Gall, S.M.; McCarthy, R.E.

1991-11-01

Macrofouling of cooling-water systems is one of the more significant and costly problems encountered in the nuclear power industry. Both marine and freshwater macroinvertebrates can be responsible for losses in plant availability because of plugged intakes and heat transfer equipment. There is a greater diversity of macrofouling organisms in marine waters than in fresh waters. Marine macrofouling organisms include barnacles, mollusks, bryozoans, and hydroids. Barnacles are crustaceans with feathery appendages, which allow them to attach to a variety of surfaces. They are a major cause of severe macrofouling because they can remain attached even after death. The major freshwater macrofoulingmore » organisms include the Asiatic Clam (Corbicula fluminea) and the newest freshwater macrofouler, the Zebra Mussel (Dreissena polymorpha). The introduction of the Zebra Mussel into the Great Lakes has created economic and ecological problems that will not easily be solved. The threat of intercontinental dispersal of the Zebra Mussel in America is serious. Research programs have been initiated around the country to develop control methods for this macrofouling problem. The various control methodologies can be classified in the following categories: biological, chemical, physical, and mechanical. Laboratory experiments were performed to evaluate the efficacy of Actibrom against mature Zebra Mussels.« less

Germination of Cherrybark and Nuttal Oak Acorns Following Flooding

Treesearch

C. B. Briscoe

1961-01-01

Frequency and duration of flooding is undoubtedly one of the most important environmental factors affecting species distribution in bottomland forests. In the life of a tree this influence is first exerted on the seed, and the capacity of seeds to retain viability after submergence by flood water may well be an important factor in determining the success of a species...

The Successful Parent: Growing Mighty Oaks from Little Acorns

ERIC Educational Resources Information Center

Metzker, Carol

2006-01-01

Appreciative intelligence is the factor that makes some people more successful than others, more resilient to life's lumps and bumps, more creative and persistent when dealing with challenges, and more often able to smile at the end of a tough day. It is the same type of intelligence found in exceptional business leaders, entrepreneurs and…

Acorn viability following prescribed fire in upland hardwood forests

Treesearch

Katie Greenberg; Tara Keyser; Stan Zarnoch; Kris Connor

2012-01-01

Restoration of structure and function of mixed-oak (Quercus spp.) forests is a focal issue of forest land managers in the eastern United States due to widespread regeneration failure and poor overstory recruitment of oaks, particularly on productive sites. Prescribed fire is increasingly used as a tool in oak ecosystem restoration, with the goal of reducing competition...

Susceptibility of sprouted oak acorns to Phytophthora ramorum zoospores

USDA-ARS?s Scientific Manuscript database

Phytophthora ramorum is a recently emerged pathogen, having established in Europe and several western U.S. states, including California and Oregon. It has a wide host range and is a threat to forest ecology and the nursery industry. In California, coast live oak (Quercus agrifolia) is a major host...

Cache placement, pilfering, and a recovery advantage in a seed-dispersing rodent: Could predation of scatter hoarders contribute to seedling establishment?

NASA Astrophysics Data System (ADS)

Steele, Michael A.; Bugdal, Melissa; Yuan, Amy; Bartlow, Andrew; Buzalewski, Jarrod; Lichti, Nathan; Swihart, Robert

2011-11-01

Scatter-hoarding mammals are thought to rely on spatial memory to relocate food caches. Yet, we know little about how long these granivores (primarily rodents) recall specific cache locations or whether individual hoarders have an advantage when recovering their own caches. Indeed, a few recent studies suggest that high rates of pilferage are common and that individual hoarders may not have a retriever's advantage. We tested this hypothesis in a high-density (>7 animals/ha) population of eastern gray squirrels ( Sciurus carolinensis) by presenting individually marked animals (>20) with tagged acorns, mapping cache sites, and following the fate of seed caches. PIT tags allowed us to monitor individual seeds without disturbing cache sites. Acorns only remained in the caches for 12-119 h (0.5-5 d). However, when we live-trapped and removed some animals from the site immediately after they stored seeds (thus simulating predation), their seed caches remained intact for significantly longer periods (16-27 d). Cache duration corresponded roughly to the time at which squirrels were returned to the study area. These results suggest that squirrels have a retriever's advantage and may remember specific cache sites longer than previously thought. We further suggest that predation of scatter hoarders who store seeds for long periods and also possess a recovery advantage may be one important mechanism by which seed establishment is achieved.

Darwin and the cirripedes: Insights and dreadful blunders.

PubMed

Deutsch, Jean S

2009-09-01

Charles Darwin's favorite animals were cirripedes (barnacles). Indeed, he worked intensively on cirripedes during the years he was maturing his thoughts regarding his theory, which eventually led to the publication of The Origin of Species. Here I present some of Darwin's achievements in the morphology, systematics and biology of these small marine invertebrates, and also, in light of our present knowledge, some mistakes he made. © 2009 ISZS, Blackwell Publishing and IOZ/CAS.

Journal of Naval Science. Volume 2. Number 3. July 1976

DTIC Science & Technology

1976-07-01

Effects of juvenile hormone analogues upon the metamorphosis of larvae of the barnacle Elminius modcstus Darwin By D. J. Tighe-Ford ... The...duction of external field and reduction of the internal effective field intersecting the armature. Shore trials of the 1 MW system are now under...and adjusted. The field coils have been taken to " quench " and confirmation obtained that the quench is safely contained with no ill- effect . The

New Marine Antifouling Compounds from the Red Alga Laurencia sp.

PubMed Central

Oguri, Yuko; Watanabe, Mami; Ishikawa, Takafumi; Kamada, Takashi; Vairappan, Charles S.; Matsuura, Hiroshi; Kaneko, Kensuke; Ishii, Takahiro; Suzuki, Minoru; Yoshimura, Erina; Nogata, Yasuyuki

2017-01-01

Six new compounds, omaezol, intricatriol, hachijojimallenes A and B, debromoaplysinal, and 11,12-dihydro-3-hydroxyretinol have been isolated from four collections of Laurencia sp. These structures were determined by MS and NMR analyses. Their antifouling activities were evaluated together with eight previously known compounds isolated from the same samples. In particular, omaezol and hachijojimallene A showed potent activities (EC50 = 0.15–0.23 µg/mL) against larvae of the barnacle Amphibalanus amphitrite. PMID:28846653

Polymer Claw: Instant Underwater Adhesive

DTIC Science & Technology

2012-10-23

April to October. The biofilms included mostly algae with patches of barnacles. 3.1.1 Removal of Biofilm with Caustic Paste The caustic paste was...when the brush was rotated 360° while it was pressed downwards. Figure 3 shows that the thick algae biofilm was completely removed under these...413 TABLE OF CONTENTS 1 SUMMARY 1 2 PROIECT GOALS AND OBJECTIVES 3. 1 KEY ACCOMPLISHMENTS 3 3.1 BIOFILM REMOVAL 3 3.1.1 REMOVAL OF BIOFILM

How Marine Conditions Affect Severity of MIC of Steels

DTIC Science & Technology

2007-07-11

to organometallic catalysis, acidification of the electrode surface, the combined effects of elevated H202 and decreased pH and the production of...various parts of I the world ocean . At least 4000 different species Splash zone 0.1 mmtiy of organisms are recorded as marine fouling "Steeli/ nuisances...limiting dissolved oxygen at the metal surface. A layer of hard- shelled organisms, such as barnacles or mussels, on steel in the splash zone (just above

Currents Through the Korea/Tsushima Strait: A Review of LINKS Observations

DTIC Science & Technology

2006-09-01

DD-MM-YYYY) 2. REPORT TYPE 3. DATES COVERED (From - To) 25-07-2007 Journal Article 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Currents Through the Korea... AVAILABILITY STATEMENT Approved for public release, distribution is unlimited. 13. SUPPLEMENTARY NOTES Korea/Tsushima Strait (KTS), Japan/East Sea (JES...ployments were based on a new type of TRBM know as a Barny (Figure 1) because it was shaped like a barnacle (Perkins et al., 2000b), while the other

Environmental Variability during the CHURCH STROKE II Cruise 5 Exercise

DTIC Science & Technology

1979-02-01

Route Z eNerth Stonington, CT 06359 ATTN: S. Elam 1 Arthur D. Little, inc. 15 Acorn Park ’ambridge, MA 02140 "ATTN. Dr, G. Roisbeck 1 W. G. Sykes 1 ...aircraft throughout these areas to coincide with acoustic events. (U) OCEANOGRAPHIC FINDINGS 1 . (U) Typhoon Lucy, a storm which packed sustained...winds of 120 mph, had only a minimal effect on the sound speed structure along the baseline as late as 2- 1 /2 days after its passage. The lack of observed

Wood thrush nest success and post-fledging survival across a temporal pulse of small mammal abundance in an oak forest.

PubMed

Schmidt, Kenneth A; Rush, Scott A; Ostfeld, Richard S

2008-07-01

1. Synchronized mass production of seed crops, such as acorns, produces a resource pulse that may have far-reaching consequences for songbird populations through its effects on avian predators. Seed production in these forests represents only the first of several pulsed events. Secondary pulses emerge as mast-consuming rodents numerically respond to seed production and tertiary pulses emerge as generalist predators, such as raptors, numerically respond to rodents. In turn, these two groups reduce nest productivity and juvenile survivorship 1 and 2 years, respectively, after the initial pulse in seed production. 2. At our study site in south-eastern New York, USA, autumn acorn abundance (primary pulse) largely determines rodent abundance (secondary pulse) the following spring. We tested the hypotheses that the population dynamics of a shrub-nesting passerine (wood thrush Hylocichla mustelina), is influenced by rodents through the: (a) direct effect of predation by rodents; (b) indirect effect of rodents on the abundance of raptors (tertiary pulse); and (c) indirect effect of rodent abundance on raptor diet. The latter specifically hypothesizes that a crash in the rodent population in the wake of region-wide failure of acorn production leads to an extreme diet shift in raptors that increases post-fledging mortality in birds. 3. We conducted a 3-year study to examine variation in wood thrush nest success and fledgling survival, using radio telemetry, across a pulse of rodent abundance (i.e. low, medium and high). We also updated and reanalysed regional wood thrush population growth rates as a function of the annual variation in rodent abundance. 4. Fledgling survivorship, but not nest success, varied in relation to annual rodent abundance. Raptors and eastern chipmunks Tamias striatus were the most commonly identified predators on fledglings. Fledgling survivorship was greatest at intermediate rodent abundance consistent with a shift in raptor diet. Regional rate of

Antifouling phenyl ethers and other compounds from the invertebrates and their symbiotic fungi collected from the South China Sea.

PubMed

Wang, Chao-Yi; Wang, Kai-Ling; Qian, Pei-Yuan; Xu, Ying; Chen, Min; Zheng, Juan-Juan; Liu, Min; Shao, Chang-Lun; Wang, Chang-Yun

2016-12-01

Marine organism-derived secondary metabolites are promising potential sources for discovering environmentally safe antifouling agents. In present study, 55 marine secondary metabolites and their synthesized derivatives were tested and evaluated for their antifouling activities and security. These compounds include 44 natural products isolated from marine invertebrates and their symbiotic microorganisms collected from the South China Sea and 11 structural modified products derived from the isolated compounds. The natural secondary metabolites, covering phenyl ether derivatives, terpenoids, 9, 11-secosteroids, anthraquinones, alkaloids, nucleoside derivatives and peptides, were isolated from two corals, one sponge and five symbiotic fungi. All of the isolated and synthesized compounds were tested for their antifouling activities against the cyprids of barnacle Balanus (Amphibalanus) amphitrite Darwin. Noticeably, five phenyl ether derivatives (9, 11, 13-15) exhibited potent anti-larval settlement activity with the EC 50 values lower than 3.05 μM and the LC 50 /EC 50 ratios higher than 15. The study of structure-activity relationship (SAR) revealed that the introduction of acetoxy groups and bromine atoms to phenyl ether derivatives could significantly improve their antifouling activities. This is the first report on the SAR of phenyl ether derivatives on antifouling activity against barnacle B. amphitrite. The polybrominated diphenyl ether derivative, 2, 4, 6, 2', 4', 6'-hexabromo-diorcinol (13), which displayed excellent antifouling activity, was considered as a promising candidate of environmentally friendly antifouling agents.

Characterization of Terpenoids from the Root of Ceriops tagal with Antifouling Activity

PubMed Central

Chen, Jun-De; Yi, Rui-Zao; Lin, Yi-Ming; Feng, Dan-Qing; Zhou, Hai-Chao; Wang, Zhan-Chang

2011-01-01

One new dimeric diterpenoid, 8(14)-enyl-pimar-2′(3′)-en-4′(18′)-en-15′(16′)-endolabr- 16,15,2′,3′-oxoan-16-one (1) and five known terpenoids: Tagalsin C (2), Tagalsin I (3), lup-20(29)-ene-3β,28-diol (4), 3-oxolup-20(29)-en-28-oic acid (5) and 28-hydroxylup- 20(29)-en-3-one (6) were isolated from the roots of the mangrove plant Ceriops tagal. Their structures and relative stereochemistry were elucidated by means of extensive NMR, IR and MS analysis. The antifouling activity against larval settlement of the barnacle Balanus albicostatus were evaluated using capsaicin as a positive control. All these terpenoids exhibited antifouling activity against cyprid larvae of the barnacle without significant toxicity. The structure-activity relationship results demonstrated that the order of antifouling activity was diterpenoid (Compound 2) > triterpenoid (Compounds 4, 5 and 6) > dimeric diterpenoid (Compounds 1 and 3). The functional groups on the C-28 position of lupane triterpenoid significantly affect the antifouling activity. The diterpenoid dimmer with two identical diterpenoid subunits might display more potent antifouling activity than one with two different diterpenoid subunits. The stability test showed that Compounds 2, 4, 5 and 6 remained stable over 2-month exposure under filtered seawater. PMID:22072902

Head regeneration in hemichordates is not a strict recapitulation of development

PubMed Central

Luttrell, Shawn M.; Gotting, Kirsten; Ross, Eric; Alvarado, Alejandro Sánchez

2016-01-01

Background: Head or anterior body part regeneration is commonly associated with protostome, but not deuterostome invertebrates. However, it has been shown that the solitary hemichordate Ptychodera flava possesses the remarkable capacity to regenerate their entire nervous system, including their dorsal neural tube and their anterior head‐like structure, or proboscis. Hemichordates, also known as acorn worms, are marine invertebrate deuterostomes that have retained chordate traits that were likely present in the deuterostome ancestor, placing these animals in a vital position to study regeneration and chordate evolution. All acorn worms have a tripartite body plan, with an anterior proboscis, middle collar region, and a posterior trunk. The collar houses a hollow, dorsal neural tube in ptychoderid hemichordates and numerous chordate genes involved in brain and spinal cord development are expressed in a similar anterior–posterior spatial arrangement along the body axis. Results: We have examined anterior regeneration in the hemichordate Ptychodera flava and report the spatial and temporal morphological changes that occur. Additionally, we have sequenced, assembled, and analyzed the transcriptome for eight stages of regenerating P. flava, revealing significant differential gene expression between regenerating and control animals. Conclusions: Importantly, we have uncovered developmental steps that are regeneration‐specific and do not strictly follow the embryonic program. Developmental Dynamics 245:1159–1175, 2016. © 2016 The Authors. Developmental Dynamics published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists PMID:27649280

Origin of Meter-Size Granite Basins in the Southern Sierra Nevada, California

USGS Publications Warehouse

Moore, James G.; Gorden, Mary A.; Robinson, Joel E.; Moring, Barry C.

2008-01-01

Meter-size granite basins are found in a 180-km belt extending south from the South Fork of the Kings River to Lake Isabella on the west slope of the southern Sierra Nevada, California. Their origin has long been debated. A total of 1,033 basins have been inventoried at 221 sites. The basins occur on bedrock granitic outcrops at a median elevation of 1,950 m. Median basin diameter among 30 of the basin sites varies from 89 to 170 cm, median depth is 12 to 63 cm. Eighty percent of the basin sites also contain smaller bedrock mortars (~1-2 liters in capacity) of the type used by Native Americans (American Indians) to grind acorns. Features that suggest a manmade origin for the basins are: restricted size, shape, and elevation range; common association with Indian middens and grinding mortars; a south- and west-facing aspect; presence of differing shapes in distinct localities; and location in a food-rich belt with pleasant summer weather. Volcanic ash (erupted A.D. 1240+-60) in the bottom of several of the basins indicates that they were used shortly before ~760 years ago but not thereafter. Experiments suggest that campfires built on the granite will weaken the bedrock and expedite excavation of the basins. The primary use of the basins was apparently in preparing food, including acorns and pine nuts. The basins are among the largest and most permanent artifacts remaining from the California Indian civilization.

Sources and methods to reconstruct past masting patterns in European oak species.

PubMed

Szabó, Péter

2012-01-01

The irregular occurrence of good seed years in forest trees is known in many parts of the world. Mast year frequency in the past few decades can be examined through field observational studies; however, masting patterns in the more distant past are equally important in gaining a better understanding of long-term forest ecology. Past masting patterns can be studied through the examination of historical written sources. These pose considerable challenges, because data in them were usually not recorded with the aim of providing information about masting. Several studies examined masting in the deeper past, however, authors hardly ever considered the methodological implications of using and combining various source types. This paper provides a critical overview of the types of archival written that are available for the reconstruction of past masting patterns for European oak species and proposes a method to unify and evaluate different types of data. Available sources cover approximately eight centuries and can be put into two basic categories: direct observations on the amount of acorns and references to sums of money received in exchange for access to acorns. Because archival sources are highly different in origin and quality, the optimal solution for creating databases for past masting data is a three-point scale: zero mast, moderate mast, good mast. When larger amounts of data are available in a unified three-point-scale database, they can be used to test hypotheses about past masting frequencies, the driving forces of masting or regional masting patterns.

A new 1,2-ethanedione benzofurane derivative from Tephrosia purpurea.

PubMed

Peng, Yan; Chen, Yinning; Gao, Chenghai; Yan, Tao; Cao, Wenhao; Huang, Riming

2014-01-01

A new 1,2-ethanedione benzofurane derivative, purpdione (1), was isolated from Tephrosia purpurea, together with seven known flavonoids, purpurenone (2), pongamol (3), ovalitenin A (4), karanjin (5), lanceolatin B (6), tachrosin (7) and villosinol (8). The new structure was elucidated based on the analysis of its spectroscopic data. The structures of the known compounds were identified by comparing their spectroscopic data with those reported in the literature. The isolates exhibited marginal ability to inhibit the settlement of barnacle (Balanus reticulatus).

Ecologically Enhancing Coastal Infrastructure

NASA Astrophysics Data System (ADS)

Mac Arthur, Mairi; Naylor, Larissa; Hansom, Jim; Burrows, Mike; Boyd, Ian

2017-04-01

Hard engineering structures continue to proliferate in the coastal zone globally in response to increasing pressures associated with rising sea levels, coastal flooding and erosion. These structures are typically plain-cast by design and function as poor ecological surrogates for natural rocky shores which are highly topographically complex and host a range of available microhabitats for intertidal species. Ecological enhancement mitigates some of these negative impacts by integrating components of nature into the construction and design of these structures to improve their sustainability, resilience and multifunctionality. In the largest UK ecological enhancement trial to date, 184 tiles (15x15cm) of up to nine potential designs were deployed on vertical concrete coastal infrastructure in 2016 at three sites across the UK (Saltcoats, Blackness and Isle of Wight). The surface texture and complexity of the tiles were varied to test the effect of settlement surface texture at the mm-cm scale of enhancement on the success of colonisation and biodiversity in the mid-upper intertidal zone in order to answer the following experimental hypotheses: • Tiles with mm-scale geomorphic complexity will have greater barnacle abundances • Tiles with cm-scale geomorphic complexity will have greater species richness than mm-scale tiles. A range of methods were used in creating the tile designs including terrestrial laser scanning of creviced rock surfaces to mimic natural rocky shore complexity as well as artificially generated complexity using computer software. The designs replicated the topographic features of high ecological importance found on natural rocky shores and promoted species recruitment and community composition on artificial surfaces; thus enabling us to evaluate biological responses to geomorphic complexity in a controlled field trial. At two of the sites, the roughest tile designs (cm scale) did not have the highest levels of barnacle recruits which were

Developing a national radiation oncology registry: From acorns to oaks.

PubMed

Palta, Jatinder R; Efstathiou, Jason A; Bekelman, Justin E; Mutic, Sasa; Bogardus, Carl R; McNutt, Todd R; Gabriel, Peter E; Lawton, Colleen A; Zietman, Anthony L; Rose, Christopher M

2012-01-01

The National Radiation Oncology Registry (NROR) is a collaborative initiative of the Radiation Oncology Institute and the American Society of Radiation Oncology, with input and guidance from other major stakeholders in oncology. The overarching mission of the NROR is to improve the care of cancer patients by capturing reliable information on treatment delivery and health outcomes. The NROR will collect patient-specific radiotherapy data electronically to allow for rapid comparison of the many competing treatment modalities and account for effectiveness, outcome, utilization, quality, safety, and cost. It will provide benchmark data and quality improvement tools for individual practitioners. The NROR steering committee has determined that prostate cancer provides an appropriate model to test the concept and the data capturing software in a limited number of sites. The NROR pilot project will begin with this disease-gathering treatment and outcomes data from a limited number of treatment sites across the range of practice; once feasibility is proven, it will scale up to more sites and diseases. When the NROR is fully implemented, all radiotherapy facilities, along with their radiation oncologists, will be solicited to participate in it. With the broader participation of the radiation oncology community, NROR has the potential to serve as a resource for determining national patterns of care, gaps in treatment quality, comparative effectiveness, and hypothesis generation to identify new linkages between therapeutic processes and outcomes. The NROR will benefit radiation oncologists and other care providers, payors, vendors, policy-makers, and, most importantly, cancer patients by capturing reliable information on population-based radiation treatment delivery. Copyright © 2012 (c) 2010 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved. Published by Elsevier Inc. All rights reserved.

Offshore oil platforms and fouling communities in the southern Arabian Gulf (Abu Dhabi).

PubMed

Stachowitsch, Michael; Kikinger, Reinhard; Herler, Jürgen; Zolda, Pamela; Geutebrück, Ernst

2002-09-01

This study examined the fouling organisms on the legs of offshore oil platforms at two sites in the southern Arabian Gulf (offshore Abu Dhabi, United Arab Emirates). 100% of the metal structures was colonized by encrusting organisms. Both the number of individuals and the total biomass tended to decrease with depth. The total weight of dead shells always exceeded that of living organisms. Sessile filter feeders dominated the biomass, whereas small mobile forms had the largest number of individuals. The biomass at the deeper platform (22 m) was dominated by bivalves, barnacles and bryozoans, while polychaetes and amphipods had the greatest number of individuals. Biomass values here ranged from 1 g/0.1 m2 at 20 m to 147 g/0.1 m2 at 5 m; the corresponding individual numbers were 266 (20 m) and 11,814 indiv./0.1 m2 (5 m). The results at the shallower platform (11 m) differed in several respects: barnacles clearly dominated over bivalves, and sponges exceeded byrozoans, while total individual numbers fell due to a decline in polychaete dominance. Biomass values here ranged from 84 g/0.1 m2 at 10 m to 153 g/0.1 m2 at 0 m; the corresponding individual numbers were 695 (10 m) and 3,125 indiv./0.1 m2 (0 m). The potential role of such fouling communities on artificial structures in the Gulf is discussed.

Adding teeth to wave action: the destructive effects of wave-borne rocks on intertidal organisms.

PubMed

Shanks, Alan L; Wright, William G

1986-06-01

Observations in rocky intertidal areas demonstrate that breaking waves 'throw' rocks and cobbles and that these missiles can damage and kill organisms. Targets in the intertidal were dented by impacts from wave-borne rocks. New dents/day in these targets was positively correlated with the daily maximum significant wave height and with new patches/day in aggregations of the barnacle Chthamalus fissus. Impact frequency was highest in the upper intertidal and varied dramatically between microhabitats on individual boulders (edges, tops and faces). These patterns were reflected in the microhabitat abundances of 'old' and 'young' barnacles. Comparisons were made of the survivorship and the frequency of shell damage in two populations of the limpet Lottia gigantea living in habitats which differed primarily in the number of moveable rocks (i.e. potential projectiles). The mortality rate and frequency of shell damage were significantly higher in the projectilerich habitat. In addition only in this habitat did the frequency of shell damage covary significantly with seasonal periods of high surf. Investigation of the response of limpet shells to impacts suggests that shell strength varies between species and increases with shell size. Species-specific patterns of non-fatal shell breakage may have evolved to absorb the energy of impacts. In two of the intertidal habitats studied, wave-borne rock damage was chronic and, at least in part, may have governed the faunal makeup of the community by contributing to the physical 'boundaries" of the environment within which the inhabitants must survive.

Facilitating the afforestation of Mediterranean polluted soils by nurse shrubs.

PubMed

Domínguez, María T; Pérez-Ramos, Ignacio M; Murillo, José M; Marañón, Teodoro

2015-09-15

The revegetation of polluted sites and abandoned agricultural soils is critical to reduce soil losses and to control the spread of soil pollution in the Mediterranean region, which is currently exposed to the greatest soil erosion risk in Europe. However, events of massive plant mortality usually occur during the first years after planting, mainly due to the adverse conditions of high irradiance and drought stress. Here, we evaluated the usefulness of considering the positive plant-plant interactions (facilitation effect) in the afforestation of polluted agricultural sites, using pre-existing shrubs as nurse plants. We used nurse shrubs as planting microsites for acorns of Quercus ilex (Holm oak) along a gradient of soil pollution in southwestern Spain, and monitored seedling growth, survival, and chemical composition during three consecutive years. Seedling survival greatly increased (from 20% to more than 50%) when acorns were sown under shrub, in comparison to the open, unprotected matrix. Facilitation of seedling growth by shrubs increased along the gradient of soil pollution, in agreement with the stress gradient hypothesis that predicts higher intensity of the facilitation effects with increasing abiotic stress. Although the accumulation of trace elements in seedling leaves was higher underneath shrub, the shading conditions provided by the shrub canopy allowed seedlings to cope with the toxicity provoked by the concurrence of low pH and high trace element concentrations in the most polluted sites. Our results show that the use of shrubs as nurse plants is a promising tool for the cost-effective afforestation of polluted lands under Mediterranean conditions. Copyright © 2015 Elsevier Ltd. All rights reserved.

Mid-winter food use and body weights of mallards and wood ducks in Mississippi

USGS Publications Warehouse

Delnicki, D.; Reinecke, K.J.

1986-01-01

We obtained esophageal food samples from 311 mallards (Anas platyrhynchos) and 94 wood ducks (Aix sponsa) and body weights from 2,118 mallards and 315 wood ducks in western Mississippi during December and January 1979-83. On average, mallards ingested 3.0% animal food, principally aquatic invertebrates, and 97.0% plant food. Rice, soybeans, and seeds of 'moist soil' plants provided 41.3, 41.6, and 10-11% of the total food intake. Wood ducks ingested nearly 100% plant food, of which 23.4% was soybeans and 74.3% was acorns from Nuttall (Quercus nuttallii), water (Q. nigra), and willow oaks (Q. phellos). Mallard food use varied with water conditions; the use of rice decreased and soybeans increased during 1980-81 when cumulative November-January precipitation was < 50% of normal. Wood duck food use varied with habitat; the diet included more acorns at sites having larger acreages of intact bottomland hardwood forest. Mallard and wood duck body weights varied within and among winters. Mallard weights decreased by about 2% from December to January each year. We considered this a regulated loss, whereas we attributed increases and decreases of 4-5% in average weights during wet and dry winters to changes in feeding opportunities associated with winter precipitation. Wood duck weights followed similar trends. We concluded that continued drainage in the Mississippi Delta will adversely affect waterfowl foraging opportunities, and that research on winter feeding ecology will progress more rapidly if we develop an understanding of the foraging efficiencies associated with alternate food resources.

Resource intensification and osteoarthritis patterns: changes in activity in the prehistoric Sacramento-San Joaquin Delta region.

PubMed

Cheverko, Colleen M; Bartelink, Eric J

2017-10-01

Ethnohistoric accounts and archaeological research from Central California document a shift from the use of lower-cost, high-ranked resources (e.g., large game) toward the greater use of higher-cost, low-ranked resources (e.g., acorns and small seeds) during the Late Holocene (4500-200 BP). The subsistence transition from higher consumption of large game toward an increased reliance on acorns was likely associated with increases in levels of logistical mobility and physical activity. This study predicts that mobility and overall workload patterns changed during this transition to accommodate new food procurement strategies and incorporate new dietary resources during the Late Holocene in Central California. Osteoarthritis prevalence was scored in the shoulder, elbow, hip, and knee of adult individuals (n = 256) from seven archaeological sites in the Sacramento-San Joaquin Delta region. Comparisons were made between osteoarthritis prevalence, sex, age-at-death, and time period using ANCOVAs. The results of this study indicate significant increases in osteoarthritis prevalence in the hip of adult males and females during the Late Period (1200-200 BP), even after correcting for the cumulative effects of age. No differences were observed between the sexes or between time periods for the shoulder, elbow, and knee joints. The temporal increase in hip osteoarthritis supports the hypothesis that there was an increasing need for greater logistical mobility over time to procure key resources away from the village sites. Additionally, the lack of sex differences in osteoarthritis prevalence may suggest that females and males likely performed similar levels of activity during these periods. © 2017 Wiley Periodicals, Inc.

Identification of Genes Differentially Expressed During Heat Shock Treatment in Aedes aegypti

DTIC Science & Technology

2009-01-01

Chan, C. W. Cheng, and R. S. Wu. 2003. Cloning of theHSP70 gene in barnacle larvae and its expression under hypoxic conditions. Mar. Pollut. Bull. 46...665Ð671. Chuang, K. H., S. H. Ho, and Y. L. Song. 2007. Cloning and expression analysis of heat shock cognate 70 gene pro- moter in tiger shrimp ...in larvae , but not adults, of a polar insect. Proc. Natl. Acad. Sci. U.S.A. 103: 14223Ð14227. Robich, R. M., J. P. Rinehart, L. J. Kitchen, and D. L

Late-stage divergent synthesis and antifouling activity of geraniol-butenolide hybrid molecules.

PubMed

Takamura, Hiroyoshi; Ohashi, Takumi; Kikuchi, Takahiro; Endo, Noriyuki; Fukuda, Yuji; Kadota, Isao

2017-07-05

Hybrid molecules consisting of geraniol and butenolide were designed and synthesized by the late-stage divergent strategy. In the synthetic route, ring-closing metathesis was utilized for the construction of a butenolide moiety. A biological evaluation of the eight synthetic hybrid compounds revealed that these molecules exhibit antifouling activity against the cypris larvae of the barnacle Balanus (Amphibalanus) amphitrite with EC 50 values of 0.30-1.31 μg mL -1 . These results show that hybridization of the geraniol and butenolide structural motifs resulted in the enhancement of the antifouling activity.

KSC-08pd2104

NASA Image and Video Library

2008-06-30

CAPE CANAVERAL, Fla. – A young white-tailed deer is spotted in the brush near Launch Complex 14 at Cape Canaveral Air Force Station, Fla., adjacent to NASA's Kennedy Space Center. White-tailed deer are found in forest edge habitats statewide. They feed primarily on twigs and leaves. Their diet also includes acorns, fruits and mushrooms. Kennedy shares a boundary with the Merritt Island National Wildlife Refuge, which encompasses 92,000 acres that are a habitat for more than 330 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles. Photo credit: NASA/Dimitri Gerondidakis

KSC-08pd2105

NASA Image and Video Library

2008-06-30

CAPE CANAVERAL, Fla. – A young white-tailed deer is spotted in the brush near Launch Complex 14 at Cape Canaveral Air Force Station, Fla., adjacent to NASA's Kennedy Space Center. White-tailed deer are found in forest edge habitats statewide. They feed primarily on twigs and leaves. Their diet also includes acorns, fruits and mushrooms. Kennedy shares a boundary with the Merritt Island National Wildlife Refuge, which encompasses 92,000 acres that are a habitat for more than 330 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles. Photo credit: NASA/Dimitri Gerondidakis

ESD testing of the 8S actuator (u)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mchugh, Douglas C

2010-12-03

The 8S actuator is a hot-wire initiated explosive component used to drive the W76-1 2X Acorn 1V valve. It is known to be safe from human electrostatic discharge (ESD) pin-to-pin and all pin-to-cup stimuli as well as 1 amp/1 watt safe. However low impedance (furniture) ESD stimuli applied pin-to-pin has not been evaluated. Components were tested and the results analyzed. The 8S actuator has been shown to be immune to human and severe furniture ESD, whether applied pin-to-pin or pin-to-cup.

Prehistoric Agricultural Communities in West Central Alabama. Volume 2. Studies of Material Remains from the Lubbub Creek Archaeological Locality.

DTIC Science & Technology

1983-01-01

trianguloid. They lacked ., 5., 179 a,.x ,2 3 4 5 6 9 10 11 12 13 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 37 38 39 40 41 42 43 44 45 46...resource ans would have supplied sugars, vitamins, and minerals to the diet . Dennell (1976) questioned whether the frequency of sr-as o- grains on site can...arbohydrate content, but a lower protein content than hickory nuts and black walnuts. * . . 241 10 20 30 40 50 60 70 80 90 :00 MILLER III hickory acorn

Learn, how to learn

NASA Astrophysics Data System (ADS)

Narayanan, M.

2002-12-01

Ernest L. Boyer, in his 1990 book, "Scholarship Reconsidered: Priorities of the Professorate" cites some ground breaking studies and offers a new paradigm that identifies the need to recognize the growing conversation about teaching, scholarship and research in the Universities. The use of `ACORN' model suggested by Hawkins and Winter to conquer and mastering change, may offer some helpful hints for the novice professor, whose primary objective might be to teach students to `learn how to learn'. Action : It is possible to effectively change things only when a teaching professor actually tries out a new idea. Communication : Changes are successful only when the new ideas effectively communicated and implemented. Ownership : Support for change is extremely important and is critical. Only strong commitment for accepting changes demonstrates genuine leadership. Reflection : Feedback helps towards thoughtful evaluation of the changes implemented. Only reflection can provide a tool for continuous improvement. Nurture : Implemented changes deliver results only when nurtured and promoted with necessary support systems, documentation and infrastructures. Inspired by the ACORN model, the author experimented on implementing certain principles of `Total Quality Management' in the classroom. The author believes that observing the following twenty principles would indeed help the student learners how to learn, on their own towards achieving the goal of `Lifelong Learning'. The author uses an acronym : QUOTES : Quality Underscored On Teaching Excellence Strategy, to describe his methods for improving classroom teacher-learner participation. 1. Break down all barriers. 2. Create consistency of purpose with a plan. 3. Adopt the new philosophy of quality. 4. Establish high Standards. 5. Establish Targets / Goals. 6. Reduce dependence on Lectures. 7. Employ Modern Methods. 8. Control the Process. 9. Organize to reach goals. 10. Prevention vs. Correction. 11. Periodic Improvements. 12

ACORNS: A Tool for the Visualisation and Modelling of Atypical Development

ERIC Educational Resources Information Center

Moore, D. G.; George, R.

2011-01-01

Across many academic disciplines visualisation and notation systems are used for modelling data and developing theory, but in child development visual models are not widely used; yet researchers and students of developmental difficulties may benefit from a visualisation and notation system which can clearly map developmental outcomes and…

The influence of load carrying on the energetics and kinematics of terrestrial locomotion in a diving bird

PubMed Central

Tickle, Peter G.; Lean, Samantha C.; Rose, Kayleigh A. R.; Wadugodapitiya, Avanti P.; Codd, Jonathan R.

2013-01-01

Summary The application of artificial loads to mammals and birds has been used to provide insight into the mechanics and energetic cost of terrestrial locomotion. However, only two species of bird have previously been used in loading experiments, the cursorial guinea fowl (Numida meleagris) and the locomotor-generalist barnacle goose (Branta leucopsis). Here, using respirometry and treadmill locomotion, we investigate the energetic cost of carrying trunk loads in a diving bird, the tufted duck (Aythya fuligula). Attachment of back loads equivalent to 10% and 20% of body mass increased the metabolic rate during locomotion (7.94% and 15.92%, respectively) while sternal loads of 5% and 10% had a greater proportional effect than the back loads (metabolic rate increased by 7.19% and 13.99%, respectively). No effect on locomotor kinematics was detected during any load carrying experiments. These results concur with previous reports of load carrying economy in birds, in that there is a less than proportional relationship between increasing load and metabolic rate (found previously in guinea fowl), while application of sternal loads causes an approximate doubling of metabolic rate compared to back loads (reported in an earlier study of barnacle geese). The increase in cost when carrying sternal loads may result from having to move this extra mass dorso-ventrally during respiration. Disparity in load carrying economy between species may arise from anatomical and physiological adaptations to different forms of locomotion, such as the varying uncinate process morphology and hindlimb tendon development in goose, guinea fowl and duck. PMID:24244861

Towards a Solution to the Goose-Agriculture Conflict in North Norway, 1988–2012: The Interplay between Policy, Stakeholder Influence and Goose Population Dynamics

PubMed Central

Tombre, Ingunn M.; Eythórsson, Einar; Madsen, Jesper

2013-01-01

This paper presents results from a multidisciplinary study of a negotiation process between farmers and wildlife authorities which led to an agricultural subsidy scheme to alleviate conflicts between agriculture and geese in Norway. The Svalbard-breeding population of pink-footed geese Anser brachyrhynchus has increased considerably over the last decades and conflicts with farmers have escalated, especially at stopover sites in spring when geese feed on newly sprouted pasture grass. In Vesterålen, an important stopover site for geese in North Norway, farmers deployed scaring of geese at varying intensity dependent on the level of conflict during 1988–2012. We assessed the efficiency of a subsidy scheme established in 2006, in terms of its conflict mitigation, reflected in a near discontinuation of scaring activities. The presence of pink-footed geese was analysed in relation to scaring intensity, the total goose population size and the increasing occurrence of another goose species, the barnacle goose Branta leucopsis. Scaring significantly affected the number of geese staging in Vesterålen, both in absolute and relative terms (controlling for total population size). The geese responded immediately to an increased, and reduced, level of scaring. Despite the establishment of the subsidy scheme, the number of pink-footed geese has recently declined which is probably caused by the increasing number of barnacle geese. For the farmers, the subsidy scheme provides funding that reduces the economic costs caused by the geese. Sustaining a low level of conflict will require close monitoring, dialogue and adaptation of the subsidy scheme to cater for changes in goose population dynamics. PMID:23977175

Does proximity to urban centres affect the dietary regime of marine benthic filter feeders?

NASA Astrophysics Data System (ADS)

Puccinelli, Eleonora; Noyon, Margaux; McQuaid, Christopher D.

2016-02-01

Threats to marine ecosystems include habitat destruction and degradation of water quality, resulting from land- and ocean-based human activities. Anthropogenic input causing modification of water quality, can affect primary productivity and thus food availability and quality for higher trophic levels. This is especially important for sedentary benthic intertidal communities, which rely on local food availability. We investigated the effect of urbanization on the dietary regime of four species of intertidal filter feeders (three barnacles and one mussel) at sites close to high-density cities and at sites far from heavily urbanized areas using fatty acid and stable isotope techniques. δ15N was significantly higher at urbanized sites compared to their corresponding control sites for all species with few exceptions, while no effect on δ13C was recorded. Barnacle fatty acid profiles were not affected by cities, while mussels from sites close to cities had fatty acid signatures with a higher proportion of polyunsaturated fatty acids (PUFA). We suggest that the enrichment in δ15N at urbanised sites reflects the influence of anthropogenically derived nitrogen directly linked to wastewater input from domestic and industrial sewage. Linked to this, the high proportion of PUFA in mussels at urbanized sites may reflect the influence of increased nitrogen concentrations on primary production and enhanced growth of large phytoplankton cells. The results indicate that anthropogenic effects can strongly influence the diets of benthic organisms, but these effects differ among taxa. Changes in the diet of such habitat forming species can affect their fitness and survival with potential effects on the populations associated with them.

Genetic diversity and structure of Megabalanus azoricus in the Azores: Implications for aquaculture management

NASA Astrophysics Data System (ADS)

De Girolamo, Mirko; Torboli, Valentina; Pallavicini, Alberto; Isidro, Eduardo

2017-11-01

Megabalanus azoricus giant barnacles are the most traditional seafood of the Azores archipelago (NE Atlantic). This valuable commercial species has been highly exploited in the past and it is considered one of the key species for the development of aquaculture in the region. Despite the importance for conservation and aquaculture there is still a lack of basic information about M. azoricus genetic diversity and population structure. Here we used seven microsatellites markers to analyse 300 samples collected at six out of nine islands of the Azores archipelago, including also different locations from a single island, to provide information on the scale of genetic diversity and population structure of this species. Parameters like heterozygosity, allelic richness and effective number of alleles indicated a high genetic diversity and variability among islands. Pairwise comparisons and PCoA analysis on FST and Jost's DEST showed significant and evident differentiation among sampling locations. Additionally, AMOVA allocates a small (6.02%) but statistically significant portion of the variance to the among Island level revealing also a weak resolution (1.87%) at finer scale. Additionally Monte Carlo resampling methods indicated the most likely sources of the recruits were the local or adjacent populations. Genetic risks associated with the giant barnacle potential production scheme should be taken into account in a future management plan delimiting, as precautionary measure, this culture at a single island or at groups of islands here identified. Moreover a monitoring strategy should be implemented with the aim to evaluate possible changes in genetic parameters of native populations.

mtDNA from fossils reveals a radiation of Hawaiian geese recently derived from the Canada goose (Branta canadensis)

PubMed Central

Paxinos, Ellen E.; James, Helen F.; Olson, Storrs L.; Sorenson, Michael D.; Jackson, Jennifer; Fleischer, Robert C.

2002-01-01

Phylogenetic analysis of 1.35 kb of mtDNA sequence from fossils revealed a previously unknown radiation of Hawaiian geese, of which only one representative remains alive (the endangered Hawaiian goose or nene, Branta sandvicensis). This radiation is nested phylogenetically within a living species, the Canada goose (Branta canadensis) and is related most closely to the large-bodied lineage within that species. The barnacle goose (Branta leucopsis) is also nested within the Canada goose species and is related most closely to the small-bodied lineage of Canada geese. The peripheral isolation of the barnacle goose in the Palearctic apparently allowed the evolution of its distinctive plumage pattern, whereas the two Nearctic lineages of Canada geese share a primitive plumage pattern. The Hawaiian lineage of Canada geese diverged more dramatically, splitting into at least three species that differ in body size, body proportions, and flight ability. One fossil species, limited to the island of Hawaii, was related closely to the nene but was over four times larger, flightless, heavy-bodied and had a much more robust cranium. Application of a rate calibration to levels of DNA divergence suggests that this species evolved on the island of Hawaii in less than 500,000 years. This date is consistent with the potassium/argon-based age of the island of Hawaii of 430,000–500,000 years. The giant Hawaii goose resembles the moa-nalos, a group of massive, extinct, flightless ducks that lived on older Hawaiian Islands and thus is an example of convergent evolution of similar morphologies in island ecosystems. PMID:11818543

Can acclimation of thermal tolerance, in adults and across generations, act as a buffer against climate change in tropical marine ectotherms?

PubMed

Morley, S A; Nguyen, K D; Peck, L S; Lai, C-H; Tan, K S

2017-08-01

Thermal acclimation capacity was investigated in adults of three tropical marine invertebrates, the subtidal barnacle Striatobalanus amaryllis, the intertidal gastropod Volegalea cochlidium and the intertidal barnacle Amphibalanus amphitrite. To test the relative importance of transgenerational acclimation, the developmental acclimation capacity of A. amphitrite was investigated in F 1 and F 2 generations reared at a subset of the same incubation temperatures. The increase in CT max (measured through loss of key behavioural metrics) of F 0 adults across the incubation temperature range 25.4-33.4°C was low: 0.00°C (V. cochlidium), 0.05°C (S. amaryllis) and 0.06°C (A. amphitrite) per 1°C increase in incubation temperature (the acclimation response ratio; ARR). Although the effect of generation was not significant, across the incubation temperature range of 29.4-33.4°C, the increase in CT max in the F 1 (0.30°C) and F 2 (0.15°C) generations of A. amphitrite was greater than in the F 0 (0.10°C). These correspond to ARR's of 0.03°C (F 0 ), 0.08°C (F 1 ) and 0.04°C (F 2 ), respectively. The variability in CT max between individuals in each treatment was maintained across generations, despite the high mortality of progeny. Further research is required to investigate the potential for transgenerational acclimation to provide an extra buffer for tropical marine species facing climate warming. Copyright © 2016 Elsevier Ltd. All rights reserved.

Investigation of the role of hydrophilic chain length in amphiphilic perfluoropolyether/poly(ethylene glycol) networks: towards high-performance antifouling coatings.

PubMed

Wang, Yapei; Pitet, Louis M; Finlay, John A; Brewer, Lenora H; Cone, Gemma; Betts, Douglas E; Callow, Maureen E; Callow, James A; Wendt, Dean E; Hillmyer, Marc A; DeSimonea, Joseph M

2011-01-01

The facile preparation of amphiphilic network coatings having a hydrophobic dimethacryloxy-functionalized perfluoropolyether (PFPE-DMA; M(w) = 1500 g mol(-1)) crosslinked with hydrophilic monomethacryloxy functionalized poly(ethylene glycol) macromonomers (PEG-MA; M(w) = 300, 475, 1100 g mol(-1)), intended as non-toxic high-performance marine coatings exhibiting antifouling characteristics is demonstrated. The PFPE-DMA was found to be miscible with the PEG-MA. Photo-cured blends of these materials containing 10 wt% of PEG-MA oligomers did not swell significantly in water. PFPE-DMA crosslinked with the highest molecular weight PEG oligomer (ie PEG1100) deterred settlement (attachment) of algal cells and cypris larvae of barnacles compared to a PFPE control coating. Dynamic mechanical analysis of these networks revealed a flexible material. Preferential segregation of the PEG segments at the polymer/air interface resulted in enhanced antifouling performance. The cured amphiphilic PFPE/PEG films showed decreased advancing and receding contact angles with increasing PEG chain length. In particular, the PFPE/PEG1100 network had a much lower advancing contact angle than static contact angle, suggesting that the PEG1100 segments diffuse to the polymer/water interface quickly. The preferential interfacial aggregation of the larger PEG segments enables the coating surface to have a substantially enhanced resistance to settlement of spores of the green seaweed Ulva, cells of the diatom Navicula and cypris larvae of the barnacle Balanus amphitrite as well as low adhesion of sporelings (young plants) of Ulva, adhesion being lower than to a polydimethyl elastomer, Silastic T2.

Continued development of a detailed model of arc discharge dynamics

NASA Technical Reports Server (NTRS)

Beers, B. L.; Pine, V. W.; Ives, S. T.

1982-01-01

Using a previously developed set of codes (SEMC, CASCAD, ACORN), a parametric study was performed to quantify the parameters which describe the development of a single electron indicated avalanche into a negative tip streamer. The electron distribution function in Teflon is presented for values of the electric field in the range of four-hundred million volts/meter to four billon volts/meter. A formulation of the scattering parameters is developed which shows that the transport can be represented by three independent variables. The distribution of ionization sites is used to indicate an avalanche. The self consistent evolution of the avalanche is computed over the parameter range of scattering set.

New developments in demographic targeting--the implications of 1991.

PubMed

Humby, C R

1989-01-01

This paper examines benefits that systems such as ACORN, a demographic marketing system that classifies neighborhoods, offer today and monitors some of the trends. It then considers the impact of the 1992 UK census and gives a view of what marketeers can expect in the next 5 years. Neighborhood classifications represent a summary of the consumption patterns of a set of neighbors. If we could reach individuals based on the current life stage the gains to be had would be as great again as that offered by the neighborhood classifications themselves. The greatest weakness of all the neighborhood-based systems is their inability to target at life stage or age.

Pathfinder Rear Ramp

NASA Image and Video Library

1997-07-06

NASA's Mars Pathfinder's rear rover ramp can be seen successfully unfurled in this image, taken at the end of Sol 2 by the Imager for Mars Pathfinder (IMP). This ramp was later used for the deployment of the microrover Sojourner, which occurred at the end of Sol 2. Areas of a lander petal and deflated airbag are visible at left. The image helped Pathfinder scientists determine that the rear ramp was the one to use for rover deployment. At upper right is the rock dubbed "Barnacle Bill," which Sojourner will later study. http://photojournal.jpl.nasa.gov/catalog/PIA00627

Fine morphology of frontal filaments in nauplii of cirriped crustaceans.

PubMed

Obukhova, A L; Voronezhskaya, E E; Malakhov, V V

2016-05-01

Fine morphology of the frontal filaments (FFs) at all nauplius stages of two barnacle species (Verruca stroemia and Hesperibalanus hesperius) has been investigated by scanning electron microscopy. FFs have been detected at the second nauplius stage and persist during all stages. FFs contain a wide proximal and a fine distal parts, but they are not actually separated as segments of the limbs, and the area between them looks like a single cuticular crease. Apical and subapical pores have been found at the top of each FF in the larvae of both species, which may indicate the chemoreceptor function of these organs.

A molecular dynamics study on the adsorption of a mussel protein on two different films: Polymer film and a SAM

NASA Astrophysics Data System (ADS)

He, Cunxue; Zhang, Heng; Lin, Cunguo; Wang, Li; Yuan, Shiling

2017-05-01

The adhesion of marine life would produce a certain degree of corrosion effect on the hull surface. Shellfish organisms, such as barnacles and mussels, were always used to research the impediment of coating material to protein adsorption. In this work, the adsorbed behaviors of mussel protein on the PDMS and C7F16-SAM surfaces were explored by molecular dynamics (MD) simulations. Simulation results showed that protein was strongly adsorbed onto the hydrophobic surface, as reflected by the large interaction energy; while the adsorption onto the hydrophilic PDMS surface was weak due to two strongly adhered water layers.

Parasitic castration: the evolution and ecology of body snatchers

USGS Publications Warehouse

Lafferty, Kevin D.; Kuris, Armand M.

2009-01-01

Castration is a response to the tradeoff between consumption and longevity faced by parasites. Common parasitic castrators include larval trematodes in snails, and isopod and barnacle parasites of crustaceans. The infected host (with its many unique properties) is the extended phenotype of the parasitic castrator. Because an individual parasitic castrator can usurp all the reproductive energy from a host, and that energy is limited, intra- and interspecific competition among castrators is generally intense. These parasites can be abundant and can substantially depress host density. Host populations subject to high rates of parasitic castration appear to respond by maturing more rapidly.

Environmentally Benign and Permanent Modifications to Prevent Biofouling on Marine and Hydrokinetic Devices

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zheng Zhang

2012-04-19

Semprus Biosciences is developing environmentally benign and permanent modifications to prevent biofouling on Marine and Hydrokinetic (MHK) devices. Biofouling, including growth on external surfaces by bacteria, algae, barnacles, mussels, and other marine organisms, accumulate quickly on MHK devices, causing mechanical wear and changes in performance. Biofouling on crucial components of hydrokinetic devices, such as rotors, generators, and turbines, imposes substantial mass and hydrodynamic loading with associated efficiency loss and maintenance costs. Most antifouling coatings leach toxic ingredients, such as copper and tributyltin, through an eroding process, but increasingly stringent regulation of biocides has led to interest in the development ofmore » non-biocidal technologies to control fouling. Semprus Biosciences research team is developing modifications to prevent fouling from a broad spectrum of organisms on devices of all shapes, sizes, and materials for the life of the product. The research team designed and developed betaine-based polymers as novel underwater coatings to resist the attachment of marine organisms. Different betaine-based monomers and polymers were synthesized and incorporated within various coating formulations. The formulations and application methods were developed on aluminum panels with required adhesion strength and mechanical properties. The coating polymers were chemically stable under UV, hydrolytic and oxidative environments. The sulfobetaine formulations are applicable as nonleaching and stable underwater coatings. For the first time, coating formulations modified with highly packed sulfobetaine polymers were prepared and demonstrated resistance to a broad spectrum of marine organisms. Assays for comparing nonfouling performance were developed to evaluate protein adsorption and bacteria attachment. Barnacle settlement and removal were evaluated and a 60-day field test was performed. Silicone substrates including a

A new deep-sea balanomorph barnacle (Cirripedia: Thoracica: Bathylasmatidae) from Chile.

PubMed

Araya, Juan Francisco; Newman, William Anderson

2018-01-01

Deep waters of the South Pacific off northern Chile remain poorly studied, particularly in regard to invertebrate faunas. Some recent works include new records on deep-water species, mostly from the bycatch of benthic fisheries concentrated along the continental margin of the country. Among these, a few specimens of an unidentified bathylasmatine balanomorph were collected off Caldera, northern Chile, and they are described here as Bathylasma chilense sp. nov. While this is the second report of a bathylasmatid in the Eastern Pacific Ocean, the first being Tetrachaelasma southwardi Newman & Ross, 1971, it is not only the first but the deepest known (1800-2000 m) species of Bathylasma. Its discovery increases the number of described Bathylasma species to eight, four of which are extant. This is the third deep-water balanomorph cirriped recorded for the region where it may represent an isolate from a West Wind Drift fauna, an immigrant from the western Pacific, or a relict of a once cosmopolitan Paleocene-Eocene fauna now having an amphitropical component.

Identification of an intact ParaHox cluster with temporal colinearity but altered spatial colinearity in the hemichordate Ptychodera flava

PubMed Central

2013-01-01

Background ParaHox and Hox genes are thought to have evolved from a common ancestral ProtoHox cluster or from tandem duplication prior to the divergence of cnidarians and bilaterians. Similar to Hox clusters, chordate ParaHox genes including Gsx, Xlox, and Cdx, are clustered and their expression exhibits temporal and spatial colinearity. In non-chordate animals, however, studies on the genomic organization of ParaHox genes are limited to only a few animal taxa. Hemichordates, such as the Enteropneust acorn worms, have been used to gain insights into the origins of chordate characters. In this study, we investigated the genomic organization and expression of ParaHox genes in the indirect developing hemichordate acorn worm Ptychodera flava. Results We found that P. flava contains an intact ParaHox cluster with a similar arrangement to that of chordates. The temporal expression order of the P. flava ParaHox genes is the same as that of the chordate ParaHox genes. During embryogenesis, the spatial expression pattern of PfCdx in the posterior endoderm represents a conserved feature similar to the expression of its orthologs in other animals. On the other hand, PfXlox and PfGsx show a novel expression pattern in the blastopore. Nevertheless, during metamorphosis, PfXlox and PfCdx are expressed in the endoderm in a spatially staggered pattern similar to the situation in chordates. Conclusions Our study shows that P. flava ParaHox genes, despite forming an intact cluster, exhibit temporal colinearity but lose spatial colinearity during embryogenesis. During metamorphosis, partial spatial colinearity is retained in the transforming larva. These results strongly suggest that intact ParaHox gene clustering was retained in the deuterostome ancestor and is correlated with temporal colinearity. PMID:23802544

Pasta quality as impacted by the type of flour and starch and the level of egg addition.

PubMed

Saleh, Mohammed; Al-Ismail, Khalid; Ajo, Radwan

2017-10-01

This study investigated the effects of substituting wheat flour with fractions of different starch types and egg levels on pasta quality. First order mixture response surface model was used where the effects of various starch types and egg levels on pasta quality were evaluated. Coefficients of estimation were determined and fractional contribution of wheat, starch type and egg levels were evaluated. Egg levels negatively (p < .05) impacted treatments pasting viscosities, except in potato starch and rice flour. Stabilized rice bran peak viscosity increased from 215.0 to 3420.0 cP with decrease in egg level from 33 to 0%. Flow behavior index of treatments solution with various fractions of starch types and egg level ranged from 0.34 to 1.42 and was significantly (p < .05) lower than control (i.e., 2.15) indicating a better fit as a shear thinning model. Water holding capacity values of acorn starch and lupine flour were the greatest among treatment ranging from 86.8% to 176.0% and from 83.3% to 152.0%, respectively. Results also showed a possible modification of cooked pasta quality including firmness, stickiness, cooking loss, and water uptake, keeping with consumer acceptability through varying starch type and egg level. Results show that flour and starch type and egg level interaction play significant role in pasta blends formulation. Moreover, substitution of wheat flour with acorn, native or modified corn and potato starches fractions, as well as with lupine, rice, tapioca, and stabilized rice bran flours would have significant effects on the physical properties and acceptability of various cereal products. For instance, the use of rice bran in potentially developed products would enhance the consumption of whole grain foods, resulting in improved intake of fiber and other healthy components. © 2016 Wiley Periodicals, Inc.

Tropical insect diversity: evidence of greater host specialization in seed-feeding weevils.

PubMed

Peguero, Guille; Bonal, Raúl; Sol, Daniel; Muñoz, Alberto; Sork, Victoria L; Espelta, Josep M

2017-08-01

Host specialization has long been hypothesized to explain the extraordinary diversity of phytophagous insects in the tropics. However, addressing this hypothesis has proved challenging because of the risk of over-looking rare interactions, and hence biasing specialization estimations, and the difficulties to separate the diversity component attributable to insect specialization from that related to host diversity. As a result, the host specialization hypothesis lacks empirical support for important phytophagous insect clades. Here, we test the hypothesis in a radiation of seed-feeding insects, acorn weevils (Curculio spp.), sampled in temperate and tropical regions (California and Nicaragua, respectively) with an equivalent pool of oak host species. Using DNA sequences from three low-copy genes, we delimited to species level 778 weevil larvae extracted from host seeds and assessed their phylogenetic relationships by Maximum Likelihood and Bayesian inference. We then reconstructed the oak-weevil food webs and examined differences in alpha, beta and gamma diversity using Hill numbers of effective species. We found a higher alpha, beta and gamma diversity of weevils in Nicaragua compared to California despite similar richness of host species at both local and regional level. By means of Bayesian mixed models, we also found that tropical weevil species were highly specialized both in terms of host range and interaction strength, whereas their temperate congeners had a broader taxonomic and phylogenetic host spectrum. Finally, in Nicaraguan species, larval body size was highly correlated with the size of the acorns infested, as would be expected by a greater host specialization, whereas in California this relationship was absent. Altogether, these lines of evidence support the host specialization hypothesis and suggest contrasting eco-evolutionary dynamics in tropical and temperate regions even in absence of differences in host diversity. © 2017 by the Ecological

Numerical and behavioral effects within a pulse-driven system: consequences for shared prey.

PubMed

Schmidt, Kenneth A; Ostfeld, Richard S

2008-03-01

Some of the clearest examples of the ramifying effects of resource pulses exist in deciduous forests dominated by mast-producing trees, such as oaks, beech, and hornbeam. Seed production in these forests represents only the first of several pulsed events. Secondary pulses emerge as mast-consuming small rodents numerically respond to seed production and tertiary pulses emerge as generalist predators numerically respond to rodents. Raptors may also respond behaviorally (i.e., diet shifts) to subsequent crashes in small rodents following the crash phase in seed production. In oak-dominated forest in the Hudson Valley, New York, these various pulse and crash phases act synergistically, although not simultaneously, to influence thrush population dynamics through predation on nests, juveniles, and adults. As a consequence, factors limiting population growth rate and their age-specific action vary as a function of past acorn production. We highlight these interactions based on our eight-year study of thrush demography, acorn production, and small mammal abundance coupled with information on regional adult thrush population trends from the Breeding Bird Survey. We use these data sets to demonstrate the sequence of primary to tertiary pulses and how they influence breeding thrush populations. To extend our discussion beyond masting phenomena in the eastern United States, we briefly review the literature of alternative avian prey within pulsed systems to show (1) numerical and behavioral responses by generalist predators are ubiquitous in pulsed systems, and this contributes to (2) variability in reproduction and survivorship of avian prey linked to the underlying dynamics of the pulse. We conclude by exploring the broad consequences of cascading resource pulses for alternative prey based upon the indirect interaction of apparent competition among shared prey and the nature of temporal variability on populations.

Sampling design for long-term regional trends in marine rocky intertidal communities

USGS Publications Warehouse

Irvine, Gail V.; Shelley, Alice

2013-01-01

Probability-based designs reduce bias and allow inference of results to the pool of sites from which they were chosen. We developed and tested probability-based designs for monitoring marine rocky intertidal assemblages at Glacier Bay National Park and Preserve (GLBA), Alaska. A multilevel design was used that varied in scale and inference. The levels included aerial surveys, extensive sampling of 25 sites, and more intensive sampling of 6 sites. Aerial surveys of a subset of intertidal habitat indicated that the original target habitat of bedrock-dominated sites with slope ≤30° was rare. This unexpected finding illustrated one value of probability-based surveys and led to a shift in the target habitat type to include steeper, more mixed rocky habitat. Subsequently, we evaluated the statistical power of different sampling methods and sampling strategies to detect changes in the abundances of the predominant sessile intertidal taxa: barnacles Balanomorpha, the mussel Mytilus trossulus, and the rockweed Fucus distichus subsp. evanescens. There was greatest power to detect trends in Mytilus and lesser power for barnacles and Fucus. Because of its greater power, the extensive, coarse-grained sampling scheme was adopted in subsequent years over the intensive, fine-grained scheme. The sampling attributes that had the largest effects on power included sampling of “vertical” line transects (vs. horizontal line transects or quadrats) and increasing the number of sites. We also evaluated the power of several management-set parameters. Given equal sampling effort, sampling more sites fewer times had greater power. The information gained through intertidal monitoring is likely to be useful in assessing changes due to climate, including ocean acidification; invasive species; trampling effects; and oil spills.

Modelling of the impact of biofouling on hydrodynamics downstream of a tidal turbine

NASA Astrophysics Data System (ADS)

Bennis, A. C.; Rivier, A.; Dauvin, J. C.

2016-02-01

Biological organisms, like barnacles, mussels or bryozoans, colonize rapidly an immersed surface and could form a thickness until several centimeters on it. This biofouling could modify hydrodynamics around tidal turbine by increasing drag and hence resistance and could be detrimental to the performance of turbine (e.g. Orme et al., 2001; Khor and Xiao, 2011). Our work focuses on modifications of vortices downstream of a tidal turbine due to biofouling using CFD. Fixed biological organisms are solved explicitly by the model and are considered by modifying the blade profile. Firstly an airfoil colonized by barnacles is modelled for various fouling height and spacing and results are compared to experimental and simulated data (Orme et al., 2001; Khor and Xiao, 2011) in order to assess the capacity of the model to reproduce the flow around a blade with biofouling. Then a Darrieus vertical axis tidal turbine is modelled using a dynamic mesh. Configuration with smooth clean blades is assessed by comparison with experiments and simulations made by Roa (2011) and Bossard (2012). Biological organisms with various heights, spacing and shapes are fixed on blades and wakes downstream of clean and colonized tidal turbine are compared. Vorticity fields around the tidal turbine are clearly modified when blades are colonized. Samples will be taken from location where farms are planned to be built (Alderney Race/Raz Blanchard) to characterize more precisely the characteristics of species which are liable to fix on tidal turbine.Reference:Bossard (2012). Doctoral dissertation, Université de Grenoble.Khor & Xiao. (2011). Ocean Eng, 38(10), 1065-1079. Orme et al. (2001). Marine Renewable Energy Conference, Newcastle.Roa (2011).Doctoral dissertation, Université de Grenoble.

Chthamalus montagui as biomonitor of metal contamination in the northwest coast of Portugal.

PubMed

Reis, Pedro A; Salgado, Maria Antónia; Vasconcelos, Vitor

2012-09-01

The concentrations of seven metals (Cd, Cr, Cu, Fe, Mn, Ni and Zn) were determined in coastal seawaters and soft and hard tissues of the barnacle Chthamalus montagui from the northwest coast of Portugal to assess the potential use of C. montagui as biomonitor of metal contamination. The results of this study showed that C. montagui soft tissues can be used for monitoring metal bioavailabilities in these coastal seawaters: (1) there were significant correlations (p < 0.05) between the metal concentrations in soft tissues and their concentrations in seawaters and (2) barnacle soft tissues were sensitive to spatial variation of metal bioavailabilities, accumulating different amounts of metals in different locations. The range of concentrations in tissues were: 0.59-1.7 mg Cd kg(-1), 0.5-3.2 mg Cr kg(-1), 0.72-3.0 mg Ni kg(-1), 1.2-6.7 mg Cu kg(-1), 9-26 mg Mn kg(-1), 214-785 mg Fe kg(-1) and 178-956 mg Zn kg(-1); (3) mean logarithmic bioaccumulation factors (log BAF) of Fe, Cr and Cd were higher, 5.49, 4.93 and 4.46, respectively, than mean log BAFs of Mn, Zn, Cu and Ni, 4.03, 3.97, 3.74 and 3.61, respectively. In contrary, C. montagui shell plates were not a good matrix to monitor metal bioavailability in these coastal seawaters, with no significant correlations (p < 0.05) between metal concentrations in the shell and in seawater. Regarding the high Zn concentrations obtained in the coastal seawaters and C. montagui soft tissues, all seawaters from northwest coast of Portugal should be classified as "moderately/remarkably polluted".