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1

33 CFR 117.570 - Sassafras River.  

Code of Federal Regulations, 2013 CFR

...DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Maryland § 117.570 Sassafras River. The draw of the...River (Route 213) bridge, mile 10.0 at Georgetown, Maryland, shall open on signal; except that from...

2013-07-01

2

Some demographic aspects of the Canela Indians of Brazil.  

PubMed

Census and ethnographic information were used to explain population change between 1970 and 1988 among the Canela population of Ramkokamekra living at Escalvado in northeast Brazil. The first ethnographic evidence was collected by William Crocker in 1957. An official census was conducted in 1970 and was followed by censuses in 1975, 1979, and 1988. The Canela were exposed to white contact in 1750, but their geographic location in the hills made settler contact minimal between 1840 and 1940. In 1963, after attacks on the cattle of the backlanders, the Canela were moved to the Guajajara Indian reservation at Sardinha, and eventually were returned to their homeland. Society was matrilocal and matrilateral; during the study period, mortality declined and the population became younger. Fertility remained stable because extramarital sex declined and an increase in age at marriage offset fertility-enhancing declines in breast feeding. There were improvements in health and nutrition. The crude death rate declined from 53/1000 population for 1970-75 to 29/1000 for 1975-79, and mostly affected mortality among women and children. Age distribution of the population showed changes from a young population to a population with a high proportion of young and old. The dependency ratio between 1970 and 1988 went from .84 to 1.38. A high sex ratio was evidenced, which may have been due in 1988 to the need for old-age pensions. Marriage was matrilocal and endogamous to the tribe. Divorce and separation increased over time, but was still low, particularly for men. Multiple sex partners made certain that women did not remain childless. Adult female status was achieved when childbirth occurred. Young husbands joined their wives in the maternal household, which reduced extramarital relations. When a mother died, the child was secure in having a home with her mother's mother or her mother's sister. The arrival of health services in 1970 and an anthropologist trained nurse led to better treatment for tuberculosis and improvements in health, particularly alcohol misuse. A missionary couple in 1968 added new wells for improved sanitation. The Canela, having been influenced by the backlanders on whom they depended for economic support and by the Indian service, have gradually been moving toward a more rigid and Western definition of sex roles, greater disapproval of homosexuality, and less extramarital sex. PMID:12319066

Greene, M E; Crocker, W H

1994-03-01

3

Forensic profiling of sassafras oils based on comprehensive two-dimensional gas chromatography.  

PubMed

Safrole, the main compound in the essential oil of several plants of the Laurel family (Lauraceae), and its secondary product piperonylmethylketone are the predominantly used precursors for the illicit synthesis of 3,4-methylenedioxymethamphetamine (MDMA) which is, in turn, the most common active ingredient in Ecstasy tablets. Analytical methods with adequate capacity to identify links and origin of precursors, such as safrole, provide valuable information for drug-related police intelligence. Authentic sassafras oil samples from police seizures were subjected to comparative analysis based on their chemical profiles obtained by comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GC × GC-TOFMS). The enhanced separation power and increased sensitivity of GC × GC allowed for the detection of minor compounds present in the essential oils which were of particular interest in case of very pure samples whose impurity profiles were not very pronounced. Discrimination of such samples was still possible even in the absence of characteristic main compounds. PMID:23683915

Schäffer, M; Gröger, T; Pütz, M; Zimmermann, R

2013-04-24

4

Mutagenicity and recombinagenicity of Ocotea acutifolia (Lauraceae) aporphinoid alkaloids.  

PubMed

The somatic mutation and recombination test (SMART) in wing cells of Drosophila melanogaster was used to test the mutagenic and recombinogenic activities of five aporphinoid alkaloids isolated from Ocotea acutifolia: thalicminine (1), (+)-dicentrine (2), (+)-ocoteine (3), (+)-6S-ocoteine N-oxide (4), and (+)-leucoxine (5). Third-stage larvae derived from the standard cross with wing cell markers mwh and/or flr(3) were treated chronically. The frequencies of mutant spots observed in marked heterozygous descendants revealed significant dose-dependent genotoxicity for alkaloids 1-4; compounds 1 and 2 were the most active. Alkaloids 1-4 also induced mitotic recombination. The presence of a methoxyl group at C-3 (as in compound 3) lowers its genotoxic effect relative to that of unsubstituted analogue 2, and the introduction of an N-oxide functionality (3 vs. 4) further reduces genotoxicity. The very planar conformation of oxo-aporphine alkaloid 1 may account for its higher genotoxicity vs. its less-planar analogues 3 and 4. As previously reported for (+)-dicentrine (2), alkaloids 1, 3, and 4 may also be DNA intercalating agents, interfering with the catalytic activity of topoisomerases. PMID:23892138

Guterres, Zaira da Rosa; da Silva, Ana Francisca Gomes; Garcez, Walmir Silva; Garcez, Felipe Rodrigues; Fernandes, Carlos Alexandre; Garcez, Fernanda Rodrigues

2013-07-24

5

Sassafras oil overdose  

MedlinePLUS

... Daubert GP, Spoerke DG. Poisonous plants. In: Shannon MW, Borron SW, Burns MJ, eds. Haddad and Winchester's ... C. Herbal, traditional, and alternative medicine. In: Shannon MW, Borron SW, Burns MJ, eds. Haddad and Winchester's ...

6

Morphological and physiological changes in Leishmania promastigotes induced by yangambin, a lignan obtained from Ocotea duckei  

Microsoft Academic Search

We have previously demonstrated that yangambin, a lignan obtained from Ocotea duckei Vattimo (Lauraceae), shows antileishmanial activity against promastigote forms of Leishmania chagasi and Leishmania amazonensis. The aim of this study was to determine the in vitro effects of yangambin against these parasites using electron and confocal microscopy. L. chagasi and L. amazonensis promastigotes were incubated respectively with 50?g\\/mL and

Rubens L. Monte Neto; Louisa M. A. Sousa; Celidarque S. Dias; José M. Barbosa Filho; Márcia R. Oliveira; Regina C. B. Q. Figueiredo

2011-01-01

7

Repetitive Somatic Embryogenesis of Ocotea catharinensis Mez. (Lauraceae): Effect of Somatic Embryo Developmental Stage and Dehydration  

Microsoft Academic Search

Repetitive embryogenesis of Ocotea catharinensis from globular\\/early cotyledonary somatic embryos was successfully supported by WPM supplemented with 22.7 g l?1 sorbitol, 20 g l?1 sucrose, 400 mg l?1 glutamine and 2 g l?1 Phytagel. The best medium to induce repetitive embryogenesis in cotyledonary somatic embryos was half strength WPM supplemented\\u000a with 20 g l?1 sucrose, 400 mg l?1 glutamine, 1.5

Alessandra dos Santos Olmedo; Geraldine de Andrade Meyer; Jonice Macedo; Wagner de Amorim; Ana Maria Viana

2004-01-01

8

Chemical composition and biological activities of Ishpingo essential oil, a traditional Ecuadorian spice from Ocotea quixos (Lam.) Kosterm. (Lauraceae) flower calices  

Microsoft Academic Search

The essential oil of Ishpingo (Ocotea quixos, Lauraceae) fruit calices was analysed by GC (gas chromatography) and GC–MS (gas chromatography–mass spectrometry). Fourty-four compounds were identified. The main components detected were trans-cinnamaldehyde (27.9%), methylcinnamate (21.6%), 1,8-cineole (8.0%), benzaldehyde (3.6%), and ?-selinene (2.1%). In vitro antioxidant properties of the essential oil, obtained by DPPH (1,1-diphenyl-2-picrylhydrazyl) and ?-carotene bleaching assays, were also evaluated.

Renato Bruni; Alessandro Medici; Elisa Andreotti; Carlo Fantin; Mariavittoria Muzzoli; Marco Dehesa; Carlo Romagnoli; Gianni Sacchetti

2004-01-01

9

The typification of Cordia flavescens Aubl., the transfer of Firensia Scop. from Cordia L. (Cordiaceae, Boraginales) to the synonymy of Ocotea Aubl. (Lauraceae), and the identity of the species of Firensia  

PubMed Central

Abstract Firensia Scop. was based on Cordia flavescens Aubl., a species described and illustrated from a mixed collection that Scopoli never transferred to Firensia. The genus included three additional species formally named by Rafinesque. Currently the four species are placed in three different families and none retained the epithet accepted by Scopoli or given by Rafinesque for reason of priority. A lectotype is designated for Cordia flavescens that places Firensia in the synonymy of Ocotea (Lauraceae).

Feuillet, Christian

2013-01-01

10

Effect of tree species and end seal on attractiveness and utility of cut bolts to the redbay ambrosia beetle and granulate ambrosia beetle (coleoptera: Curculionidae: Scolytinae).  

PubMed

The redbay ambrosia beetle, Xyleborus glabratus Eichhoff, is a non-native invasive pest and vector of the fungus that causes laurel wilt disease in certain trees of the family Lauraceae. This study assessed the relative attractiveness and suitability of cut bolts of several tree species to X. glabratus. In 2009, female X. glabratus were equally attracted to traps baited with swampbay (Persea palustris (Rafinesque) Sargent) and camphortree (Cinnamomum camphora (L.) J. Presl), which were more attractive than avocado (Persea americana Miller), lancewood (Ocotea coriacea (Swartz) Britton), and sweetbay (Magnolia virginiana L.). These species were more attractive than loblolly bay (Gordonia lasianthus (L.) J. Ellis). X. glabratus entrance hole density and emergence from caged bolts were highest on swampbay and camphortree. In 2010, swampbay was significantly more attractive to X. glabratus than sassafras (Sassafras albidum (Nuttall) Nees), yellow poplar (Liriodendron tulipifera L.), and eastern redbud (Cercis canadensis L.). Sassafras bolts end sealed with a liquid wax-and-water emulsion were more attractive to X. glabratus than end-sealed bolts of yellow poplar and redbud. Relative to unsealed bolts, end seal decreased X. glabratus entrance hole density on swampbay and decreased granulate ambrosia beetle (Xylosandrus crassiusculus (Motschulsky)) trap catch, entrance hole density, and adult emergence from swampbay. X. crassiusculus was not attracted to sassafras, yellow poplar, and redbud and was not more attracted to manuka oil than to unbaited traps. Sassafras was more attractive to X. glabratus than previously reported and supported reproducing populations of the insect. End sealing bolts with a wax-and-water emulsion may not be optimal for attracting and rearing ambrosia beetles in small logs. PMID:22606816

Mayfield, A E; Hanula, J L

2012-04-01

11

Archaeological Survey and Partial Testing of a Channelization Project Item 2, Parcel 2 Above Lake 9 in Fulton County, Sassafras Ridge, Kentucky.  

National Technical Information Service (NTIS)

Six sites were located within or partially within the proposed channelization project. These sites were mainly thin components from the Woodland Period. One had a Mississippian component. Three sites were tested and no additional testing was needed.

J. M. Schock T. W. Langford R. L. Alvey

1980-01-01

12

21 CFR 189.180 - Safrole.  

Code of Federal Regulations, 2013 CFR

... H10 O2 . It is a natural constituent of the sassafras plant. Oil of sassafras is about 80 percent safrole. Isosafrole...Additive Safety (HFS-200), Center for Food Safety and Applied Nutrition, Food and Drug Administration, 5100 Paint Branch...

2013-04-01

13

Is California bay laurel a suitable host for the non-native redbay ambrosia beetle, vector of laurel wilt disease?  

Technology Transfer Automated Retrieval System (TEKTRAN)

Laurel wilt is a deadly vascular disease of trees in the Lauraceae that kills healthy redbay (Persea borbonia), sassafras (Sassafras albidum), and other related hosts. The fungal pathogen (Raffaelea lauricola) and it vector, the redbay ambrosia beetle (Xyleborus glabratus) are native to Asia and ha...

14

21 CFR 310.531 - Drug products containing active ingredients offered over-the-counter (OTC) for the treatment of...  

Code of Federal Regulations, 2010 CFR

...rosin, rosin cerate, sassafras oil, sulfur, thymol, triclosan, and zinc oxide have been present in OTC boil treatment...product that contains benzocaine, ichthammol, sulfur, or triclosan initially introduced or initially delivered for...

2010-04-01

15

21 CFR 310.531 - Drug products containing active ingredients offered over-the-counter (OTC) for the treatment of...  

Code of Federal Regulations, 2010 CFR

...rosin, rosin cerate, sassafras oil, sulfur, thymol, triclosan, and zinc oxide have been present in OTC boil treatment...product that contains benzocaine, ichthammol, sulfur, or triclosan initially introduced or initially delivered for...

2009-04-01

16

Assessing TNT Toxicity on Soils With Contrasting Characteristics Using Soil Invertebrate Toxicity Tests.  

National Technical Information Service (NTIS)

We investigated the toxicity of 2,4,6- trinitrotoluene (TNT) to earthworm (Eisenia fetida), potworm (Enchytraeus crypticus), and springtail (Folsomia candida) in five natural soils: Sassafras sandy loam (SSL), Teller sandy loam (TSL), Richfield clay loam ...

M. Simini R. T. Checkai R. G. Kuperman C. T. Phillips J. E. Kolakowski

2004-01-01

17

Comparative fluorine uptake by plants in limed and unlimed soil  

Microsoft Academic Search

Investigations were undertaken to determine the extent to which fluorine can be absorbed from soils by plant roots, and the extent to which the absorption can be controlled by liming. Sassafras loamy sand, having a pH value near 5.0 and containg 12 ppm of naturally occurring fluorine, was tranported from near Springtown Corners, NJ, to a greenhouse of the Division

ANNIE M. HURD-KARRER

1950-01-01

18

Fluorine: its toxicity to plants and its control in soils  

Microsoft Academic Search

Four series of studies with Sassafras sandy loam and loam soils were carried out to determine the concentration at which F becomes toxic to buckwheat and tomato plants. Corrective measures were studied for overcoming the toxic effects of high F concentrations in the soils.

A. L. Prince; F. E. Bear; E. G. Brennan; I. A. Leone; R. H. Daines

1949-01-01

19

Toxicity of emerging energetic soil contaminant CL20 to potworm Enchytraeus crypticus in freshly amended or weathered and aged treatments  

Microsoft Academic Search

We investigated the toxicity of an emerging polynitramine energetic material hexanitrohexaazaisowurtzitane (CL-20) to the soil invertebrate species Enchytraeus crypticus by adapting then using the Enchytraeid Reproduction Test (ISO\\/16387:2003). Studies were designed to develop ecotoxicological benchmark values for ecological risk assessment of the potential impacts of accidental release of this compound into the environment. Tests were conducted in Sassafras Sandy Loam

Roman G. Kuperman; Ronald T. Checkai; Michael Simini; Carlton T. Phillips; J. Steven Anthony; Jan E. Kolakowski; Emily A. Davis

2006-01-01

20

Antibacterial activity of 11 essential oils against Bacillus cereus in tyndallized carrot broth  

Microsoft Academic Search

The antibacterial activity of 11 essential oils from aromatic plants against the strain INRA L2104 of the foodborne pathogen Bacillus cereus grown in carrot broth at 16 °C was studied. The quantity needed by the essential oils of nutmeg, mint, clove, oregano, cinnamon, sassafras, sage, thyme or rosemary to produce 14–1110% relative extension of the lag phase was determined. Total

M. Valero; M. C. Salmerón

2003-01-01

21

Environmental Toxicity of the Explosives RDX and TNT in Soil to the Soil Invertebrate Folsomia candida.  

National Technical Information Service (NTIS)

We investigated the toxicity of hexahydro-1,3,5- trinitro-1,3,5- triazine (RDX) and 2,4,6-trinitrotoluene (TNT) to the soil invertebrate Folsomia candida (Collembola) in five natural soils: Sassafras sandy loam (SSL), Teller sandy loam (TSL), Richfield cl...

C. T. Phillips R. T. Checkai R. G. Kuperman M. Simini J. E. Kolakowski

2004-01-01

22

Food Habit Study of Striped Bass Post Yolk-Sac Larvae.  

National Technical Information Service (NTIS)

Striped bass post yolk-sac larvae and zooplankton were sampled simultaneously during May, 1977 at three locations near the mouth of the Sassafras River in Upper Chesapeake Bay. Diel variations in post-larval stomach content volume during five 24-hour stud...

P. E. Miller

1978-01-01

23

Visible Ozone Injury on Forest Trees in Great Smoky Mountains National Park, USA  

Microsoft Academic Search

During the summer of 1991 ozone injury trend plots in Great Smoky Mountains National Park, USA, consisting of mature black cherry, sassafras and yellow-poplar were established near three ozone monitors, ranging in elevation from 597-1265 m. Beginning in mid-August 1991-1993, three exposed branches each from the upper- and mid- to lower-crown of each tree were collected and evaluated for ozone

A. Chappelka; G. Somers; J. Renfro

1999-01-01

24

Biological reactive intermediates (BRIs) formed from botanical dietary supplements.  

PubMed

The use of botanical dietary supplements is increasingly popular, due to their natural origin and the perceived assumption that they are safer than prescription drugs. While most botanical dietary supplements can be considered safe, a few contain compounds, which can be converted to biological reactive intermediates (BRIs) causing toxicity. For example, sassafras oil contains safrole, which can be converted to a reactive carbocation forming genotoxic DNA adducts. Alternatively, some botanical dietary supplements contain stable BRIs such as simple Michael acceptors that react with chemosensor proteins such as Keap1 resulting in induction of protective detoxification enzymes. Examples include curcumin from turmeric, xanthohumol from hops, and Z-ligustilide from dang gui. Quinones (sassafras, kava, black cohosh), quinone methides (sassafras), and epoxides (pennyroyal oil) represent BRIs of intermediate reactivity, which could generate both genotoxic and/or chemopreventive effects. The biological targets of BRIs formed from botanical dietary supplements and their resulting toxic and/or chemopreventive effects are closely linked to the reactivity of BRIs as well as dose and time of exposure. PMID:20970412

Dietz, Birgit M; Bolton, Judy L

2010-10-21

25

A rapid diversification of rainforest trees ( Guatteria; Annonaceae) following dispersal from Central into South America  

Microsoft Academic Search

Several recent studies have suggested that a substantial portion of today’s plant diversity in the Neotropics has resulted from the dispersal of taxa into that region rather than vicariance, but more data are needed to substantiate this claim. Guatteria (Annonaceae) is, with 265 species, the third largest genus of Neotropical trees after Inga (Fabaceae) and Ocotea (Lauraceae), and its widespread

Roy H. J. Erkens; Lars W. Chatrou; Jan W. Maas; Timotheüs van der Niet; Vincent Savolainen

2007-01-01

26

Toxicity and uptake of cyclic nitramine explosives in ryegrass Lolium perenne  

Microsoft Academic Search

Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), and 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) are cyclic nitramines used as explosives. Their ecotoxicities have been characterized incompletely and little is known about their accumulation potential in soil organisms. We assessed the toxicity and uptake of these explosives in perennial ryegrass Lolium perenne L. exposed in a Sassafras sandy loam (SSL) or in a sandy soil (DRDC, CL-20 only)

Sylvie Rocheleau; Bernard Lachance; Roman G. Kuperman; Jalal Hawari; Sonia Thiboutot; Guy Ampleman; Geoffrey I. Sunahara

2008-01-01

27

Manganese toxicity in soil for Eisenia fetida, Enchytraeus crypticus (Oligochaeta), and Folsomia candida (Collembola).  

PubMed

The U.S. Environmental Protection Agency is developing Ecological Soil Screening Level (Eco-SSL) benchmarks for ecological risk assessment (ERA) of contaminants at Superfund sites. Eco-SSLs are developed from published values whenever sufficient quantity and quality of data exist. Because insufficient information was available to generate an Eco-SSL for Mn, standardized toxicity testing was undertaken to fill the data gaps. Tests included the earthworm (Eisenia fetida) cocoon production test, the enchytraeid (Enchytraeus crypticus) reproduction test, and the collembolan (Folsomia candida) reproduction test, all conducted in Sassafras sandy loam soil that supports a relatively high bioavailability of metals. Weathering and aging of manganese-amended soil were carried out to more closely simulate exposure effects at Superfund sites on soil invertebrates. Data were analyzed by nonlinear regression to determine EC20 and EC50 values based on concentration-response relationships. The toxicity order for manganese in Sassafras sandy loam was E. crypticus>E. fetida>F. candida, with EC20 values of 116, 629, and 1209 mg kg(-1), respectively. The Eco-SSL requirement for the testing of multiple representative species is well justified. All study results will be submitted to the Eco-SSL Task Group for quality control review prior to inclusion in the Eco-SSL database. PMID:14659366

Kuperman, R G; Checkai, R T; Simini, M; Phillips, C T

2004-01-01

28

Topical skin care formulations comprising plant extracts  

US Patent & Trademark Office Database

Disclosed are compositions and corresponding methods of their use that include plant, plant parts, or extracts thereof from Michelia magnifica, Xylosma japonicum, Prunus cerasifera, Nyssa sinensis, Chimonanthus praecox, Sassafras tzumu, Inula helianthus-aquatica, Capparis bodinieri, Passiflora caerulea, Galium aparine, Boehmeria platyphylla, Colquhounia coccinea, Sageretia rugosa, Jasminum stephanense, Antirrhinum majus, Daphniphyllum oldhamii, Cuscuta chinensis, Salix variegate, Osmanthus parvifolius, Euphorbia trigona, Calliandra haematocephala, Excoecaria acerifolia, Dianthus chinensis, Myriophyllum spicatum, Nymphoides peltatum, Prunus salicina, Solanum coagulans, Elaeis guineensis, Rhododendron moulmainense, Spatholobus suberectus, Artabotrys hexapetalus, Hibiscus syriacus, Lonicera calcarata, Hydnocarpus hainanensis, Ilex fragilis, Antidesma venosum, Acacia pennata ssp. Kerrii, Althaea rosea, Millettia velutina, Themeda japonica, Dalbergia hancei, Ipomoea batatas, Photinia glomerate, Hippophae rhamnoides, Azadirachta indica, Karelinia caspica, Bauhinia touranensis, Eriobotrya japonicas, Anaphalis contorta, and/or Cratoxylum prunifolium, or any combination thereof.

2013-06-04

29

Apparent genetic homogeneity of spawning striped bass in the upper Chesapeak Bay  

SciTech Connect

The possible existence of genetically distinct populations of spawning striped bass (Morone saxatilis) in the river systems of the upper Chesapeake Bay was investigated by a biochemical genetic approach. Samples of blood and liver from adult fish were obtained during the 1976 spawning runs from the Rappanhannock (Virginia), Potomac, Choptank, Sassafras, Bohemia, and Elk rivers (Maryland), and Maryland waters of the Chesapeake and Delaware Canal. Samples were analyzed for frequency of occurrence of a polymorphic liver enzyme, glycerol-3-phosphate dehydrogenase, and variable serum proteins which were not correlated with age or sex. Multivariate and Bayesian analyses of these data indicate apparent genetic homogeneity of spawning bass within the upper Chesapeake Bay. If natal stream homing occurs, a sufficient number of wanderers may provide significant gene flow among river systems. The results suggest that long-term management of the fishery need not be totally on the basis of separate river units.

Sidell, B.D.; Otto, R.G.; Powers, D.A. Karweit, M.; Smith, J.

1980-01-01

30

Variation in manuka oil lure efficacy for capturing Xyleborus glabratus (Coleoptera: Curculionidae: Scolytinae), and cubeb oil as an alternative attractant.  

PubMed

Redbay ambrosia beetle, Xyleborus glabratus Eichoff, is an exotic species to North America vectoring a deadly vascular wilt disease of redbay [Persea borbonia (L.) Spreng], swampbay [P. palustris (Raf.) Sarg.], avocado (P. americana Mill.), and sassafras [Sassafras albidum (Nutt.) Nees]. Xyleborus glabratus is attracted to manuka oil lures, which are commercially available, and phoebe oil. Variable efficacy of manuka oil lures and insufficient availability of phoebe oil prompted us to investigate the reasons behind changes in manuka oil lure efficacy and to test cubeb oil, a readily available essential oil from Piper cubeba L. seeds, as an alternative attractant. Attraction, release rates and durations, and volatile composition of manuka oil lures manufactured in 2008 were compared with manuka oil lures manufactured in 2012, and to whole and a distilled fraction of cubeb oil. Manuka oil lures from 2008 were more attractive to X. glabratus than controls for 8 wk, whereas lures from 2012 were attractive for only 2 wk. Cubeb oil and the distilled fraction of it were as attractive as or more attractive than manuka oil in three trials. In gravimetric studies, manuka oil lures from 2008 and cubeb oil lures continued to release volatiles for 57 d, whereas lures from 2012 stopped after 16 d. The chemical composition of volatiles released from new manuka oil lures from 2008 was similar to 2012; however, a preservative (butylated hydroxytoluene) was detected in the 2008 lures. Cubeb oil was an effective attractant for X. glabratus that lasted 8-9 wk when released from bubble lures. PMID:23575024

Hanula, James L; Sullivan, Brian T; Wakarchuk, David

2013-04-01

31

Quantitative resistance traits and suitability of woody plant species for a polyphagous scarab, Popillia japonica Newman.  

PubMed

The Japanese beetle, Popillia japonica Newman, has an unusually broad host range among deciduous woody plants, yet it feeds only sparingly, or not at all, on certain species in the field. We evaluated beetles' preference, survival over time and fecundity on eight woody plant species historically rated as susceptible or resistant and, after verifying those ratings, tested whether resistance is correlated with so-called quantitative defense traits including leaf toughness, low nutrient content (water, nitrogen, and sugars), and relatively high amounts of tannins or saponins, traditionally associated with such plants. We further tested whether species unsuitable for Japanese beetles are also rejected by fall webworms, Hyphantria cunea (Drury) (Lepidoptera: Arctiidae), the expected outcome if the aforementioned traits serve as broad-based defenses against generalists. Choice tests supported historical resistance ratings for the selected species: tuliptree, lilac, dogwood, and Bradford callery pear were rejected by Japanese beetles, whereas sassafras, cherry plum, Virginia creeper, and littleleaf linden were readily eaten. Rejected species also were unsuitable for survival over time, or egg-laying, indicating beetles' inability to overcome the resistance factors through habituation, compensatory feeding, or detoxification. None of the aforementioned leaf traits was consistently higher or lower in the resistant or susceptible plants, and plant species rejected by Japanese beetles often were not rejected by fall webworms. Specialized secondary chemistry, not quantitative defenses, likely determines the Japanese beetle's dietary range among deciduous woody plant species it may encounter. PMID:19161699

Keathley, Craig P; Potter, Daniel A

2008-12-01

32

Soil properties affect the toxicities of 2,4,6-trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) to the enchytraeid worm Enchytraeus crypticus.  

PubMed

The authors investigated individual toxicities of 2,4,6-trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) to the potworm Enchytraeus crypticus using the enchytraeid reproduction test. Studies were designed to generate ecotoxicological benchmarks that can be used for developing ecological soil-screening levels for ecological risk assessments of contaminated soils and to identify and characterize the predominant soil physicochemical parameters that can affect the toxicities of TNT and RDX to E. crypticus. Soils, which had a wide range of physicochemical parameters, included Teller sandy loam, Sassafras sandy loam, Richfield clay loam, Kirkland clay loam, and Webster clay loam. Analyses of quantitative relationships between the toxicological benchmarks for TNT and soil property measurements identified soil organic matter content as the dominant property mitigating TNT toxicity for juvenile production by E. crypticus in freshly amended soil. Both the clay and organic matter contents of the soil modulated reproduction toxicity of TNT that was weathered and aged in soil for 3 mo. Toxicity of RDX for E. crypticus was greater in the coarse-textured sandy loam soils compared with the fine-textured clay loam soils. The present studies revealed alterations in toxicity to E. crypticus after weathering and aging TNT in soil, and these alterations were soil- and endpoint-specific. Environ Toxicol Chem 2013;32:2648-2659. © 2013 SETAC. PMID:23955807

Kuperman, Roman G; Checkai, Ronald T; Simini, Michael; Phillips, Carlton T; Kolakowski, Jan E; Lanno, Roman

2013-09-23

33

Safrole induces cell death in human tongue squamous cancer SCC-4 cells through mitochondria-dependent caspase activation cascade apoptotic signaling pathways.  

PubMed

Safrole is one of important food-borne phytotoxin that exhibits in many natural products such as oil of sassafras and spices such as anise, basil, nutmeg, and pepper. This study was performed to elucidate safrole-induced apoptosis in human tongue squamous carcinoma SCC-4 cells. The effect of safrole on apoptosis was measured by flow cytometry and DAPI staining and its regulatory molecules were studied by Western blotting analysis. Safrole-induced apoptosis was accompanied with up-regulation of the protein expression of Bax and Bid and down-regulation of the protein levels of Bcl-2 (up-regulation of the ratio of Bax/Bcl-2), resulting in cytochrome c release, promoted Apaf-1 level and sequential activation of caspase-9 and caspase-3 in a time-dependent manner. We also used real-time PCR to show safrole promoted the mRNA expressions of caspase-3, -8, and -9 in SCC-4 cells. These findings indicate that safrole has a cytotoxic effect in human tongue squamous carcinoma SCC-4 cells by inducing apoptosis. The induction of apoptosis of SCC-4 cells by safrole is involved in mitochondria- and caspase-dependent signal pathways. PMID:21591240

Yu, Fu-Shun; Huang, An-Cheng; Yang, Jai-Sing; Yu, Chun-Shu; Lu, Chi-Cheng; Chiang, Jo-Hua; Chiu, Chang-Fang; Chung, Jing-Gung

2011-05-17

34

Preliminary ecotoxicological characterization of a new energetic substance, CL-20.  

PubMed

A new energetic substance hexanitrohexaazaisowurtzitane (or CL-20) was tested for its toxicities to various ecological receptors. CL-20 (epsilon-polymorph) was amended to soil or deionized water to construct concentration gradients. Results of Microtox (15-min contact) and 96-h algae growth inhibition tests indicate that CL-20 showed no adverse effects on the bioluminescence of marine bacteria Vibrio fischeri and the cell density of freshwater green algae Selenastrum capricornutum respectively, up to its water solubility (ca. 3.6 mg l(-1)). CL-20 and its possible biotransformation products did not inhibit seed germination and early seedling (16-19 d) growth of alfalfa (Medicago sativa) and perennial ryegrass (Lolium perenne) up to 10,000 mg kg(-1) in a Sassafras sandy loam soil (SSL). Indigenous soil microorganisms in SSL and a garden soil were exposed to CL-20 for one or two weeks before dehydrogenase activity (DHA) or potential nitrification activity (PNA) were assayed. Results indicate that up to 10,000 mg kg(-1) soil of CL-20 had no statistically significant effects on microbial communities measured as DHA or on the ammonium oxidizing bacteria determined as PNA in both soils. Data indicates that CL-20 was not acutely toxic to the species or microbial communities tested and that further studies are required to address the potential long-term environmental impact of CL-20 and its possible degradation products. PMID:15234161

Gong, Ping; Sunahara, Geoffrey I; Rocheleau, Sylvie; Dodard, Sabine G; Robidoux, Pierre Yves; Hawari, Jalal

2004-08-01

35

Unsafe and potentially safe herbal therapies.  

PubMed

Unsafe and potentially safe herbal therapies are discussed. The use of herbal therapies is on the rise in the United States, but most pharmacists are not adequately prepared educationally to meet patients' requests for information on herbal products. Pharmacists must also cope with an environment in which there is relatively little regulation of herbal therapies by FDA. Many herbs have been identified as unsafe, including borage, calamus, coltsfoot, comfrey, life root, sassafras, chaparral, germander, licorice, and ma huang. Potentially safe herbs include feverfew, garlic, ginkgo, Asian ginseng, saw palmetto, St. John's wort, and valerian. Clinical trials have been used to evaluate feverfew for migraine prevention and rheumatoid arthritis; garlic for hypertension, hyperlipidemia, and infections; ginkgo for circulatory disturbances and dementia; ginseng for fatigue and cancer prevention; and saw palmetto for benign prostatic hyperplasia. Also studied in formal trials have been St. John's wort for depression and valerian for insomnia. The clinical trial results are suggestive of efficacy of some herbal therapies for some conditions. German Commission E, a regulatory body that evaluates the safety and efficacy of herbs on the basis of clinical trials, cases, and other scientific literature, has established indications and dosage recommendations for many herbal therapies. Pharmacists have a responsibility to educate themselves about herbal therapies in order to help patients discern the facts from the fiction, avoid harm, and gain what benefits may be available. PMID:10030529

Klepser, T B; Klepser, M E

1999-01-15

36

Phytotoxicity of nitroaromatic energetic compounds freshly amended or weathered and aged in sandy loam soil.  

PubMed

The toxicities of 2,4,6-trinitrotoluene (TNT), 1,3,5-trinitrobenzene (TNB), 2,4-dinitrotoluene (2,4-DNT), and 2,6-dinitrotoluene (2,6-DNT) to terrestrial plants alfalfa (Medicago sativa L.), Japanese millet (Echinochloa crusgalli L.), and perennial ryegrass (Lolium perenne L.) were determined in Sassafras sandy loam soil using seedling emergence, fresh shoot, and dry mass measurement endpoints. A 13-week weathering and aging of energetic materials in soils, which included wetting and drying cycles, and exposure to sunlight of individual soil treatments, was incorporated into the study design to better reflect the soil exposure conditions in the field than toxicity determinations in freshly amended soils. Definitive toxicity tests showed that dinitrotoluenes were more phytotoxic for all plant species in freshly amended treatments based on EC20 values for dry shoot ranging from 3 to 24mgkg(-1) compared with values for TNB or TNT ranging from 43 to 62mgkg(-1). Weathering and aging of energetic materials (EMs) in soil significantly decreased the toxicity of TNT, TNB or 2,6-DNT to Japanese millet or ryegrass based on seedling emergence, but significantly increased the toxicity of all four EMs to all three plant species based on shoot growth. Exposure of the three plant species to relatively low concentrations of the four compounds initially stimulated plant growth before the onset of inhibition at greater concentrations (hormesis). PMID:16112172

Rocheleau, Sylvie; Kuperman, Roman G; Martel, Majorie; Paquet, Louise; Bardai, Ghalib; Wong, Stephen; Sarrazin, Manon; Dodard, Sabine; Gong, Ping; Hawari, Jalal; Checkai, Ronald T; Sunahara, Geoffrey I

2005-08-19

37

Ideology and wildlands management: The case of Rondeau Provincial Park, Ontario  

NASA Astrophysics Data System (ADS)

This is a critical examination of some of the basic concepts that have guided management of parks and related reserves, often termed wildlands. Study is focussed on Rondeau Provincial Park, Ontario, and on concepts such as wilderness, primeval forest, and the Carolinian forest. Deer culling and other management policies and practices have been based upon the idea that the highly valued sassafras, tulip, and other species of the Carolinian forest are decreasing due to browsing. Field mapping and analysis of historic vegetation records indicate that this trend is not in fact occurring. Historic research also reveals difficulties in defining the Carolinian or other perceived types of forest for management purposes. A major reassessment of ideology and management policy and practice seem to be required in Rondeau and other wildlands. Vague or general concepts such as wilderness or preservation should be strongly complemented and supported by more precise statements of objectives, a learning attitude, and experimentation and research. As a result of the technical uncertainties and value judgments frequently involved, management should also be based upon the expressed preferences and continuing involvement of citizens.

Mann, D. L.; Nelson, J. G.

1980-03-01

38

Toxicity of emerging energetic soil contaminant CL-20 to potworm Enchytraeus crypticus in freshly amended or weathered and aged treatments.  

PubMed

We investigated the toxicity of an emerging polynitramine energetic material hexanitrohexaazaisowurtzitane (CL-20) to the soil invertebrate species Enchytraeus crypticus by adapting then using the Enchytraeid Reproduction Test (ISO/16387:2003). Studies were designed to develop ecotoxicological benchmark values for ecological risk assessment of the potential impacts of accidental release of this compound into the environment. Tests were conducted in Sassafras Sandy Loam soil, which supports relatively high bioavailability of CL-20. Weathering and aging procedures for CL-20 amended into test soil were incorporated into the study design to produce toxicity data that better reflect soil exposure conditions in the field compared with the toxicity in freshly amended soils. Concentration-response relationships for measurement endpoints were determined using nonlinear regressions. Definitive tests showed that toxicities for E. crypticus adult survival and juvenile production were significantly increased in weathered and aged soil treatments compared with toxicity in freshly amended soil, based on 95% confidence intervals. The median effect concentration (EC50) and EC20 values for juvenile production were 0.3 and 0.1 mg kg-1, respectively, for CL-20 freshly amended into soil, and 0.1 and 0.035 mg kg-1, respectively, for weathered and aged CL-20 soil treatments. These findings of increased toxicity to E. crypticus in weathered and aged CL-20 soil treatments compared with exposures in freshly amended soils show that future investigations should include a weathering and aging component to generate toxicity data that provide more complete information on ecotoxicological effects of emerging energetic contaminants in soil. PMID:16213571

Kuperman, Roman G; Checkai, Ronald T; Simini, Michael; Phillips, Carlton T; Anthony, J Steven; Kolakowski, Jan E; Davis, Emily A

2005-10-05

39

Acute and chronic toxicity of the new explosive CL-20 to the earthworm (Eisenia andrei) exposed to amended natural soils.  

PubMed

Monocyclic nitramine explosives such as 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) are toxic to a number of ecological receptors, including earthworms. The polycyclic nitramine CL-20 (2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane) is a powerful explosive that may replace RDX and HMX, but its toxicity is not known. In the present study, the lethal and sublethal toxicities of CL-20 to the earthworm (Eisenia andrei) are evaluated. Two natural soils, a natural sandy forest soil (designated RacFor2002) taken in the Montreal area (QC, Canada; 20% organic carbon, pH 7.2) and a Sassafras sandy loam soil (SSL) taken on the property of U.S. Army Aberdeen Proving Ground (Edgewood, MD, USA; 0.33% organic carbon, pH 5.1), were used. Results showed that CL-20 was not lethal at concentrations of 125 mg/kg or less in the RacFor2002 soil but was lethal at concentrations of 90.7 mg/kg or greater in the SSL soil. Effects on the reproduction parameters such as a decrease in the number of juveniles after 56 d of exposure were observed at the initial CL-20 concentration of 1.6 mg/kg or greater in the RacFor2002 soil, compared to 0.2 mg/kg or greater in the SSL soil. Moreover, low concentrations of CL-20 in SSL soil (approximately 0.1 mg/kg; nominal concentration) were found to reduce the fertility of earthworms. Taken together, the present results show that CL-20 is a reproductive toxicant to the earthworm, with lethal effects at higher concentrations. Its toxicity can be decreased in soils favoring CL-20 adsorption (high organic carbon content). PMID:15095901

Robidoux, Pierre Yves; Sunahara, Geoffrey I; Savard, Kathleen; Berthelot, Yann; Dodard, Sabine; Martel, Majorie; Gong, Ping; Hawari, Jalal

2004-04-01

40

Weathering and aging of 2,4,6-trinitrotoluene in soil increases toxicity to potworm Enchytraeus crypticus.  

PubMed

Energetic materials are employed in a wide range of commercial and military activities and often are released into the environment. Scientifically based ecological soil-screening levels (Eco-SSLs) are needed to identify contaminant explosive levels in soil that present an acceptable ecological risk. Insufficient information for 2,4,6-trinitrotoluene (TNT) to generate Eco-SSLs for soil invertebrates necessitated toxicity testing. We adapted the standardized Enchytraeid Reproduction Test and selected Enchytraeus crypticus for these studies. Tests were conducted in Sassafras sandy loam soil, which supports relatively high bioavailability of TNT. Weathering and aging procedures for TNT amended to test soil were incorporated into the study design to produce toxicity data that better reflect the soil exposure conditions in the field compared with toxicity in freshly amended soils. This included exposing hydrated TNT-amended soils in open glass containers in the greenhouse to alternating wetting and drying cycles. Definitive tests showed that toxicity for E. crypticus adult survival and juvenile production was increased significantly in weathered and aged soil treatments compared with toxicity in freshly amended soil based on 95% confidence intervals. The median effect concentration and 20% effective concentration for reproduction were 98 and 77 mg/kg, respectively, for TNT freshly amended into soil and 48 and 37 mg/kg, respectively, for weathered and aged TNT soil treatments. These findings of increased toxicity to E. crypticus in weathered and aged TNT soil treatments compared with exposures in freshly amended soils show that future investigations should include a weathering and aging component to generate toxicity data that provide more complete information on ecotoxicological effects of energetic contaminants in soil. PMID:16268152

Kuperman, Roman G; Checkai, Ronald T; Simini, Michael; Phillips, Carlton T; Kolakowski, Jan E; Kurnas, Carl W

2005-10-01

41

Toxicities of dinitrotoluenes and trinitrobenzene freshly amended or weathered and aged in a sandy loam soil to Enchytraeus crypticus.  

PubMed

Scientifically based ecological soil-screening levels are needed to identify concentrations of contaminant energetic materials (EMs) in soil that present an acceptable ecological risk at a wide range of military installations. Insufficient information regarding the toxicity of 2,4-dinitrotoluene (2,4-DNT), 2,6-dinitrotoluene (2,6-DNT), and 1,3,5-trinitrobenzene (TNB) to soil invertebrates necessitated toxicity testing. We adapted the standardized Enchytraeid Reproduction Test (International Standardization Organization 16387:2003) and selected Enchytraeus crypticus for these studies. Tests were conducted in Sassafras sandy loam soil, which supports relatively high bioavailability of nitroaromatic EMs. Weathering and aging procedures for EMs amended to test soil were incorporated into the study design to produce toxicity data that better reflect the soil exposure conditions in the field compared with toxicity in freshly amended soils. This included exposing hydrated, EM-amended soils in open glass containers in the greenhouse to alternating wetting and drying cycles. Definitive tests established that the order of EM toxicity to E. crypticus based on the median effect concentration values for juvenile production in either freshly amended or weathered and aged treatments was (from the greatest to least toxicity) TNB > 2,4-DNT > 2,6-DNT. Toxicity to E. crypticus juvenile production was significantly increased in 2,6-DNT weathered and aged soil treatments compared with toxicity in freshly amended soil, based on 95% confidence intervals. This result shows that future investigations should include a weathering and aging component to generate toxicity data that provide more complete information regarding ecotoxicological effects of energetic contaminants in soil. PMID:16704071

Kuperman, Roman G; Checkai, Ronald T; Simini, Michael; Phillips, Carlton T; Kolakowski, Jan E; Kurnas, Carl W

2006-05-01

42

Survival of a tertiary relict species, Liriodendron chinense (Magnoliaceae), in southern China, with special reference to village fengshui forests.  

PubMed

• Premise of the study: We investigate factors supporting the persistence in southern China of a rare Tertiary relict tree species, Liriodendron chinense, which has been almost eliminated by recent land use conversion. We hypothesize that cultural practices and traditional sustainable forest resource uses provide niches for the species' regeneration that will complement infrequent natural disturbances, while the species' survival on remote mountain slopes where there are no humans depends on natural disturbances alone. • Methods: We examined and analyzed various landscape contexts, community associations, age distributions, and regeneration patterns of Liriodendron chinense. • Key results: Forest communities containing Liriodendron chinense were of three types: (1) village fengshui forests-mature forests dominated by Tertiary relict taxa Liriodendron, Toona, and Emmenopterys, protected for their supposed spiritual value; (2) young secondary forests near villages, dominated solely by Liriodendron; and (3) old secondary forest remnants on mountain slopes far from villages, dominated by Liriodendron with other Tertiary relicts of the genera Davidia and Sassafras. The age structure of Liriodendron indicated ample recruitment in the first two forest types, where the activities of local people have provided regeneration niches for the survival of this shade-intolerant pioneer species. On the remote mountain slopes that have never been converted to agriculture, Liriodendron has survived through regeneration made possible by natural disturbances. • Conclusions: The traditional human land use, influenced by cultural values, has supplemented infrequent natural disturbances, providing regeneration niches for this and other Tertiary remnant species near villages in mountain valleys, while on uninhabited mountain slopes the species depends on natural disturbances to survive. PMID:24107584

Tang, Cindy Q; Yang, Yongchuan; Ohsawa, Masahiko; Momohara, Arata; Mu, Jingze; Robertson, Kevin

2013-10-08

43

A lagrangian-eulerian description of debris transport by a tsunami in the Lisbon waterfront  

NASA Astrophysics Data System (ADS)

Several major tsunamis are known to have struck the Portuguese coast over the past millennia (Baptista and Miranda, 2009). The Tagus estuary has great exposure to tsunami occurrences and, being bordered by the largest metropolitan area in the country, is a particularly worrisome location in what concerns safety of populations and economic losses due to disruption of built infrastructures. The last major earthquake and tsunami combination known to have critically affected the Tagus estuary dates back to November 1st 1755. This catastrophe critically damaged Lisbon's infrastructures, led to numerous casualties and priceless heritage losses. The urban tissue of the present city still bears visible the effects of the catastrophe and of the ensuing protection measures. The objective of this work is to simulate the propagation of debris carried by a 1755-like tsunami along the present-day bathimetric and altimetric conditions of Lisbon waterfront. Particular emphasis was directed to the modeling of vehicles since the tsunami is likely to affect areas that are major traffic nodes such as Alcântara, with more than 1500 vehicles in road network of about 3 km. The simulation tool employed is based on a 2DH spatial (eulerian) shallow-flow approach suited to complex and dynamic bottom boundaries. The discretization technique relies on a finite-volume scheme, based on a flux-splitting technique incorporating a reviewed version of the Roe Riemann solver (Canelas et al. 2013). Two formulations were employed to model the advection of debris: a fully coupled continuum approach, where solid bodies are described by the concentration only and an uncoupled material (lagrangian) formulation where solid bodies are tracked between two time-steps once the flow field is determined by the eulerian solver. In the latter case, concentrations are updated after tracking the solid bodies thus correcting the mass and momentum balance to be used for the next time-step. The urban tissue was thoroughly discretized with a mesh finer than street width so that the buildings would act as obstacles and the streets would bind the incoming flow. To simplify the plan-view geometry, it was assumed that buildings would retain its original shape after the earthquake. The results of the eulerian-continuum and of the lagrangian-discrete solutions are presented, compared and discussed. It was found that the patterns of deposition of the eulerian-continuum model can be considerably different to those obtained by the lagrangian-discrete solution if the latter assumes that vehicles have a small equivalent density and if momentum losses due to inter-particle collisions are neglected. Results become more similar if vehicles are considered much denser than water and that the mixture of water and solid bodies loses momentum due to particle collisions. Acknowledgements: Project PTDC/ECM/117660/2010, funded by the Portuguese Foundation for Science and Technology (FCT) has partially supported this work. References Canelas, R.; Murillo, J. & Ferreira, R.M.L. (2013) 2DH modelling of discontinuous flows over mobile beds. Accepted, Journal of Hydraulic Research, December 2012 Baptista M.A. Miranda, J.M. (2009). Revision of the Portuguese catalog of tsunamis. Nat. Hazards Earth Syst. Sci., 9, 25-42.

Conde, Daniel; Canelas, Ricardo; Baptista, Maria Ana; João Telhado, Maria; Ferreira, Rui M. L.

2013-04-01

44

Comparative Geomorphology of Salt and Tidal Freshwater Marsh Environments  

NASA Astrophysics Data System (ADS)

Temperate estuaries include a spectrum of coastal marshes ranging from highly saline near the ocean to fresh in tributaries with substantial watershed drainage. While the hydrologic, sedimentary, and geomorphic dynamics of salt marshes have been thoroughly investigated, those aspects of tidal freshwater marshes have only begun to be addressed. Based on a recent burst in research on tidal freshwater systems in Chesapeake Bay by different universities, an attempt is made here to provide comparative geomorphology. In terms of similarities, both have tidal channels whose hydraulic geometry is primarily controlled by the tidal prism. Both show decreasing sedimentation and increasing organics with elevation and distance from channels. At seasonal to interannual time scales, the morphodynamics of both show similarities in the interplay among hydroperiod, vegetation, and geomorphology. Rather than simply evolving from youth to maturity, both systems exhibit strong evidence for dynamic equilibrium between process and morphology. Despite these similarities, there are key differences that motivate further research of tidal freshwater marshes. First, whereas salt marshes are limited by sediment supply, tidal fresh ones may not be limited depending on upstream basin size. E.g., fringing marshes along Pumunkey River have very low sediment supply, while deltaic marshes in Bush River and Sassafras River are not supply-limited. Instead, the growth of deltaic fresh marshes is transport limited, as winds and tides can only generate low momentum and turbulence for sediment transport. As illustrated in multiple systems, a constant availability of sediment leads to higher sedimentation in fresh marshes. Second, in high latitude salt marshes where the tidal range is large and the climate cold, ice acts as a strong erosional agent. In fresh marshes, ice serves to sequester sediment and buffer the erosional impact of autumnal vegetation dieback. Third, the high spatial variation in plant associations in fresh marshes allows for a finer control of spatial patterns in sedimentation and erosion than is possible in salt marshes. Finally, the landscape position of fresh marshes places them near riparian forests that can supply large amounts of organics thereby promoting accretion.

Pasternack, G. B.

2002-05-01

45

Photosynthesis and growth of two rain forest species in simulated gaps under elevated CO{sub 2}  

SciTech Connect

Two species common to the temperate rain forests of New South Wales, Australia (Doryphora sassafras and Acmena smithii) were grown for 2 wk in either ambient (350 {mu}L/L) or elevated (700 {mu}L/L) CO{sub 2} concentrations and low light (30 {mu}mol photons{center_dot}m{sup {minus}2}{center_dot}s{sup {minus}1}) after which the seedlings were exposed for over 9 wk to a midday 2-h highlight period (1250 {mu}mol photons{center_dot}m{sup {minus}2}{center_dot}s{sup {minus}1}, maximum) to simulate a tree fall gap. For both species, plants grown in elevated CO{sub 2} had greater biomass than plants grown in ambient CO{sub 2}. However, relative increases in biomass were greater in Acmena, an early-successional species, than Doryphora, a late-successional species. Recovery in quantum efficiencies over time was observed for Doryphora, implying physiological acclimation to the new light environment. Doryphora plants grown in elevated CO{sub 2} had lower values of F{sub v}/F{sub m} than plants grown in ambient CO{sub 2}. Although exposure to the simulated tree fall gap dramatically increased the conversion of pigments of the xanthophyll cycle, as well as increased the total pool size of xanthophyll cycle pigments relative to total chlorophyll concentration, there were no differences in either parameter between co{sub 2} treatments. Leaves of Doryphora and those seedlings grown in elevated CO{sub 2} had greater starch concentrations than Acmena and those seedlings grown in elevated CO{sub 2} had greater starch concentrations than Acmena and those seedlings grown in ambient CO{sub 2}, respectively. The reduction in quantum efficiencies for plants grown in elevated CO{sub 2} and exposed to a simulated tree fall gap is discussed in the context of the importance of gap phase regeneration for species in rain forest ecosystems and the potential effects of global change on those processes. 37 refs., 4 figs., 2 tabs.

Roden, J.S.; Wiggins, D.J.; Ball, M.C. [Australian National Univ., Canberra (Australia)

1997-03-01

46

NTP Carcinogenesis Studies of Food Grade Geranyl Acetate (71% Geranyl Acetate, 29% Citronellyl Acetate) (CAS No. 105-87-3) in F344/N Rats and B6C3F1 Mice (Gavage Study).  

PubMed

Geranyl acetate (3,7-dimethyl-2,6-octadiene-1-ol acetate) is a colorless liquid prepared by fractional distillation of selected essential oils or by acetylation of geraniol. It is a natural constituent of more than 60 essential oils, including Ceylon citronella, palmarosa, lemon grass, petit grain, neroli bigarade, geranium, coriander, carrot, and sassafras. Geranyl acetate is used primarily as a component of perfumes for creams and soaps and as a flavoring ingredient. On the U.S. Food and Drug Administration's list of substances "generally recognized as safe," the Food Chemicals Codex (1972) specifies that geranyl acetate must contain at least 90% total esters. Carcinogenesis studies of food-grade geranyl acetate (containing approximately 29% citronellyl acetate) were conducted by administering the test chemical in corn oil by gavage to groups of 50 male and 50 female F344/N rats at doses of 1,000 or 2,000 mg/kg body weight and to groups of 50 male and 50 female B6C3F1 mice at doses of 500 or 1,000 mg/kg. Doses were administered five times per week for 103 weeks. Groups of 50 rats and 50 mice of each sex received corn oil by gavage on the same dosing schedule and served as vehicle controls. The cumulative toxicity of geranyl acetate in the 2-year study was indicated by the significantly shorter survival of high dose male rats (control, 34/50; low dose, 29/50; high dose, 18/50) and of high dose male mice (control, 31/50; low dose, 32/50; high dose, 0/50) and of dosed female mice (38/50; 15/50; 0/50) when compared with controls. Throughout most of the 2-year study, mean body weights of high dose rats and mice of each sex were lower than those of the controls. The occurrence of retinopathy or cataracts in the high dose male rats and low dose female rats as compared with the controls does not appear to be related to the administration of geranyl acetate but rather the proximity of the rats to fluorescent light. The incidence of retinopathy or cataracts (combined) was: males: control, 0/50, 0%; low dose, 1/50, 2%; high dose, 11/50, 22%; females: control, 1/50, 2%; low dose, 13/50, 26%; high dose, 2/50, 4%. Kidney tubular cell adenomas, an uncommon tumor type, were found in 2/50 (4%) low dose male rats. The historical incidence of male corn oil gavage control F344/N rats with kidney tumors is 1/250 (0.4%) at this laboratory and 4/998 (0.4%) in the program. Squamous cell papillomas in the skin were increased marginally in low dose male rats (control, 0/50; low dose, 4/50, 8%; high dose, 1/50, 2%). In addition, one low dose male rat had a squamous cell carcinoma of the skin. The incidence of low dose male rats with either squamous cell papillomas or carcinomas was greater (P<0.05) in comparison with the controls. The historical incidence of squamous cell papillomas or carcinomas (combined) in gavage control male F344/N rats is 3.6% (9/250) at this laboratory and 2.5% (25/999) throughout the program. The incidence of all epidermal tumors was not significantly elevated in dosed male rats relative to controls (control, 3/50, 6%; low dose, 6/50, 12%; high dose, 1/50, 2%). All high dose (1,000 mg/kg) male and female mice were dead by week 91 as a result of accidentally being administered 2,800 mg/kg for 3 days during week 91; survival of low dose and control male mice was comparable. Survival of high dose male and dosed female mice may have been inadequate for the detection of late-appearing tumors. No evidence of any carcinogenic effect was found in either low or high dose mice of either sex. An infection of the genital tract was probably responsible for the deaths of 14/22 control and 8/32 low dose female mice before the end of the study. Cytoplasmic vacuolization was increased in the liver and in the kidney of male and female mice and was considered to be compound related (liver-- male: control, 1/50, 2%; low dose, 7/50, 14%; high dose, 47/50, 94%; female: 1/50, 2%; 27/50, 54%; 46/50, 92%; kidney or kidney tubule--male: 0/50; 0/50; 41/50, 82%; female: 0/50; 24/49, 49%; 37/50, 74%). Under the conditions of these studi

1987-10-01