bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Bauxite Mine Restoration Operations on Topsoil Seed Reserves in the Jarrah Forest of Western Australia
Authors: Koch J. M. , Ward S. C. , Grant C. D. , Ainsworth G. L. 
Published: April 2006

AbstractWe studied the effects of soil handling operations during bauxite mining and restoration on the numbers and depth distribution of seed stored in the surface soil of the jarrah forest. Germinable seed stores were determined in four sites of undisturbed forest, these same sites after clearing and burning of forest residues, in the soil immediately following the construction of topsoil stockpiles, in the respread topsoil and then after deep ripping of the respread topsoil. Average density of germinable seed at four sites prior to disturbance was 352 m−2. After clearing and burning, the seed store had decreased to a mean 74% of the original forest soil seed store density. When the top‐soil was stockpiled prior to respreading, the seed content was further reduced to 31% in freshly constructed stockpiles and had declined to 13% after 10 months in the stockpiles. After ripping of the respread topsoil the seed content was 16% of the original forest seed store density. In one site where the topsoil was directly stripped and respread with no period of stockpiling but with a period of fallow, the seed store was 32% after respreading and then increased to 53% of the original forest store after ripping. This increase may have been caused by an underestimate of the reserves due to insufficient heating of the samples to break dormancy in fire‐requiring species. In the forest topsoils seed was concentrated in the upper few centimeters of the soil profile, whereas after the mining and restoration operations seed was evenly distributed throughout the returned soil profile to a depth of 20 cm. Small‐seeded annual species, which were common in the forest seed store, were more sensitive to the soil handing operations and declined to very low numbers, whereas hard‐seeded plant species such as Acacia spp. were less affected by the soil handling operations. Implications for bauxite mine revegetation operations include the recommendation that direct return of topsoil should be carried out wherever possible with a minimum delay between clearing, stripping, respreading, and ripping.
Rehabilitation of Semiarid Landscapes in Australia. I. Restoring Productive Soil Patches
Authors: Tongway D. J. , Ludwig J. A. 
Published: April 2006

AbstractA rehabilitation procedure designed to reestablish resource control processes in a degraded Acacia aneura woodland was successful in improving soil nitrogen and carbon content, exchange properties, and water infiltration rates. Soil respiration rates and soil fauna populations increased, and soil temperatures were moderated. The procedure comprised laying piles of branches in patches on the contour of bare, gently sloping landscapes, with the expectation that soil, water, and litter would accumulate in these branch piles, thus improving the soil habitat and its productive potential. The procedure was derived from landscape function analysis, indicating that surface water flow was the principal means of resource transfer in these landscapes. Under degradation such overland flow results in a loss of resources. This rehabilitation procedure reversed loss processes, resulting in gains in the productive potential of soils within patches. This procedure was successful despite grazing pressure being maintained throughout the experiment.
Monitoring Wetland Habitat Restoration in Southern California Using Airborne Multi spectral Video Data
Authors: Phinn S. R. , Stow D.A. , Zedler J.B. 
Published: April 2006

AbstractRemote sensing provides a complementary approach to field sampling to assess whether restored wetland areas provide suitable habitat for the Light‐footed Clapper Rail (Rallus longirostris levipes). Habitat requirements for the clapper rail are specified by the composition of vegetation species and their spatial extent in its nesting home range. A major salt marsh construction project has been completed at the Sweetwater Marsh National Wildlife Refuge (“the refuge”), San Diego County. In this paper we describe the application of image classification techniques to high‐spatial‐resolution digital video imagery (0.8‐m pixels) to delimit patches of different marsh vegetation at the refuge. Using maps of vegetation types derived from multi spectral imagery, we estimated the area occupied by each vegetation type in potential clapper rail home ranges. Preliminary field‐checking results indicate that this approach is an accurate, noninvasive and cost‐efficient means of providing ecological information for restoration monitoring in southern California's remnant wetlands.
STIMULATORY PROPERTIES OF FILTRATE FROM THE GREEN ALGA HORMOTILA BLENNISTA. I. DESCRIPTION1,2
Authors: Monahan Thomas J. , Trainor Francis R. 
Published: April 2006

SUMMARYA laboratory phenomenon involving autostimulation of growth by filtrates of the green alga Hormotila blennista is described, and stimulation attributed primarily to the secretion of organic metabolites. Filtrates obtained from actively growing cultures 1 through 4 weeks old showed maximum growth rate stimulation values in excess of 100%. Stimulatory properties of filtrate were heat labile, were not closely controlled by the starting pH within the limits normally encountered in culture, and did not result from depletion of essential nutrients. Concomitant with growth rate stimulation, filtrates characteristically extended the lag phase of culture growth. H. blennista filtrate can support bacterial growth and selectively stimulate or inhibit 2 planktonic green algae. It was suggested that extracellular organic products secreted by H. blennista during active growth could be of survival value to the organism, and could also play regulatory roles among other microorganisms in nature.
THE TOCOPHEROL, VITAMIN K, AND RELATED ISOPRENOID QUINONE COMPOSITION OF A UNICELLULAR RED ALGA (PORPHYRIDIUM CRUENTUM)1
Authors: Antia N. J. , Desai I. D. , Romilly M. J. 
Published: April 2006

SUMMARYThe total lipids of axenically cultivated cells of Porphyridium cruentum were extracted with aqueous methanol‐chloroform mixture and fractionated into neutral and polar lipids by silicic acid column chromatography. Thin‐layer and reversed‐phase paper chromatographic analyses of the neutral lipid fractions revealed the occurrence of plastoquinones (PQ) A and C, vitamin K1 (K), ubiquinone‐10 (Q10), α‐tocopherol (α‐T), and α‐tocopherolquinone (α‐TQ) in the photoautotrophically cultured alga, and the same quinones but no tocopherol in the alga grown photoheterotrophically on glycerol. The plastoquinone A and vitamin K1 were isolated, identified, and estimated by spectroscopic methods. The results indicated the following decreasing order of concentrations: autotrophic culture, PQ A > K > Q10 > PQ C, α‐TQ, α‐T; heterotrophic culture, PQ A > Q10 > K > PQ C, α‐TQ. Except for the absence of plastoquinone B, the overall quinonoid composition was in general agreement with those previously reported for multicellular members of Rhodophyta, but the concentration level in total lipid was markedly lower.
EFFECTS OF ACETATE ON THE GROWTH AND CHLOROPHYLL CONTENT OF GOLENKINIA1
Authors: Ellis Richard J. 
Published: April 2006

SUMMARYGrowth and chlorophyll synthesis by the green alga Golenkinia cease after approximately 60‐hr incubation in 0.01 M sodium acetate. These effects are immediately preceded by a rapid rise of the pH of the medium to 8.6–8.8 due to acetate uptake. The pH kinetics are due to a gradual loss of the phosphate buffer, not to the induction or activation of acetate assimilatory enzymes. However, neither high pH nor sodium acetate alone is sufficient to inhibit cell division and bleach the algae; both must be present. Additional experiments support the hypothesis that acetate alters the cells so that they become sensitive to high concentrations of OH− ions.
BIOCHEMICAL TAXONOMY OF MARINE PHYTOPLANKTON BY ELECTROPHORESIS OF ENZYMES. II. LOSS OF HETEROZYGOSITY IN CLONAL CULTURES OF THE CENTRIC DIATOMS SKELETONEMA COSTATUM AND THALASSIOSIRA PSEUDONANA1, 2
Authors: Murphy Lynda S. 
Published: April 2006

ABSTRACTAn electrophoretic survey of 12 new isolates of Thalassiosira pseudonana Hasle & Heimdal and 25 new isolates of Skeletonema costatum (Grev.) Cleve revealed several heterozygote genotypes at malate dehydrogenase (MDH) and phosphohexose isomerase (PHI) loci. The new clones were maintained in culture for 6 mo and then reasayed at these two loci. All MDH heterozygotes and halj of the PHI heterozygotes had become homozygous. This resulted in a collection of clones that are largely homozygous but that are samples of polymorphic species. The physlogical implications of this loss of heterozygosity in clonal cultures has not been analyzed. Hawever, any change in a clone that is the result of culturing conditions reduces the usefulness of that clone as a laboratory test organism for ecological correlations.
SIGNIFICANCE OF BACTERIAL‐ANABAENA (CYANOPHYCEAE) ASSOCIATIONS WITH RESPECT TO N2 FIXATION IN FRESHWATER1, 2
Authors: Paerl Hans W. , Kellar Penelope E. 
Published: April 2006

ABSTRACTThe functional aspects of specific associations between bluegreen algae and bacteria were investigated using both naturally occurring and cultured species of Anabaena. In take waters where bacteria were associated with Anabaena heterocysls, the bacteria exhibited a chemotactic response to a variety of amino acids and glucose. Earlier autoradiographic evidence that bacteria associated with heterocysts incorporate identical substrates indicates that associated bacteria probably benefit by utilizing algal excretion products. In return, the bacteria stimulate algal N2fixation. The most likely mechanism explaining such stimulation appeared to be bacterial oxygen removal in microzones (< 3 μm diam) bordering heterocysts during periods of high ambient oxygen concentrations. In the presence of bacteria, Anabaena rapidly overcame nitrogenase‐ inhibiting concentrations of oxygen. Axenic cullures had more extensive nitrogenase inhibition, and took longer to recover in response to oxygenation. Algal‐bacterial mutualism aids Anabaena in maintaining concurrent optimal N2 fixation and high photosynthetic rates in highly oxygenated surface waters.
DISTRIBUTION OF BLUEGREEN ALGAE IN A MISSISSIPPI GULF COAST SALT MARSH1
Authors: Sage William W. , Sullivan Michatl J. 
Published: April 2006

ABSTRACTEdaphic bluegreen algal communities were sampled from five menotypic angiosperm zones in Grvelline Bay Marsh near Ocean Spring. Mississippi. Samples and environmental data were taken on a quarterly basis from October 1976 to June 1977 beneath the following marsh angiosperms: Distichlis spicata (L.) Green, Scirpus olneyi gray, SPartina patens (Aiton) Muhl., Sp. alterniflora Loisel., andJuncus roemerianusScheele. Communities in all five zones were dominated by Schizothrix calcicola (Ag.) Gom. (sensu Drauet) throughout the study, while the subdominant bluegreens varied according to season. The number of individuals in all zones was greatest in the summer and lowest in the winter. An examination of the structure of the five edaphic communities indicated a single, nearly homogeneous community exists over the entire surface of the marsh shaded by a angiosperm canopy. Light intensity appears to be the major factor affecting the distribution of bluegreen algae in this salt marsh.
COPPER TOXICITY TO SKELETONEMA COSTATUM (BACILLARIOPHYCEAE)1,2
Authors: Morel N. M. L. , Rueter J. C. , Morel F. M. M. 
Published: April 2006

ABSTRACTCopper toxicity to Skeletonema costatum (Grev.) Cleve has been studied in batch cultures of chemically defined culture media. The alga is relatively insensitive to cupric ion activity, demonstrating no effect on growth up to (Cu2+) = 10−8.5 M. Cultures inoculated from stationary phase stocks exhibit a prolongation of the lag phase with increasing copper concentrations near and above the point of precipitation of the copper. The toxicity of copper is a function of the silicic acid concentration in the medium. This effect is observed in a range of Si(OH)4 concentrations (10−5 M to 10−4 M) above known values for the saturation of silicon uptake kinetics, thus suggesting an influence of copper on silicate metabolism.
PHYSIOLOGICAL INVESTIGATIONS ONALARIA ESCULENTA(LAMINARIALES, PHAEOPHYCEAE). III. EXUDATION BY THE BLADE1,2,3
Authors: Buggeln Richard G. 
Published: April 2006

ABSTRACTComparison of exudation rate of medullary conducting cells in the midrib ofAlaria esculenta(L.) Grev. showed lowest rates for the blade meristem and highest rates in the non‐growing region, 300–500 mm from the meristem. Holding plants under continuous darkness or severing the wings from the midrib reduced exudation rate by 26 and 37%, respectively. Osmotic pressure of exudate in sink (meristem) and source (non‐growing region, up to 500 mm from the meristem) were similar (34.6–36.1 · 102kpa). Pressure flow mechanism of translocation is evaluated inAlaria.
VIRUS‐LIKE PARTICLES INHYDRURUS(CHRYSOPHYCEAE)1,2
Authors: Hoffman Larry R. 
Published: April 2006

ABSTRACTVirus‐like particles (VLPs) have been found in cells of the colonial, chrysophycean algaHydrurus foetidus(Vill.) Trev. The infected cells, probably zoospores, were discovered in material fixed directly in the field. The VLPs appear either hexagonal or pentagonal when sectioned and are therefore presumed to be icosahedra, They are 50–60 nm diam. and demonstrate distinct trilaminar coals. The VLPs were observed in the cytoplasm, but not in the chloroplast or nucleus.
STUDIES OF CARBON AND NITROGEN METABOLISM BY THREE MARINE PHYTOPLANKTON SPECIES IN NITRATE‐LIMITED CONTINUOUS CULTURE1,2
Authors: Laws Edward A. , Wong Diana C. L. 
Published: April 2006

ABSTRACTCharacteristics of carbon production, excretion and dark respiration, and nitrate uptake kinetics were studied using continuous culture techniques forThalassiosira alleniiTakano, Monorhrysis lutheri Droop and Dunaliella tertiolcctaButcher. FurT. allenii.the ratio of dark C loss to daytime net C production varied between 0.1 and 0.2 over a growth rate range from ca. 0.005 to 0.06 h‐1. ForM. lutheriandD. tertiolecta.this same ratio varied belween 0.2 and 0.3 between growth rates of ca. 0.005 and 0.025 h‐1, but declined at higher growth rates when the dark nitrate uptake capacity of the cells was exceeded by the pumping rate. Carbon excretion rates averaged less than 1.5% of daytime net C production rates. Productivity indices showed little correlation with growth rate, due to the significant poisitive correlation between chla:C ratios and growth rate. Chlorophylla:C ratios forT. alleniiwere less than 0.01 al growth rates less than 0.03 h‐1, and appoached zero at zero growth rate. Dark nitrate maximum uptake rates forM. lutheri, D. tertiolectaandT. alleniiaveraged 23, 64 and 120%, respectively, of light nitrate maximum uptake rates. Excretion of nitrite was observed during most nitrate uptake experiments. This excretion reduced net uptake of nitrate spikes in the dark forM. lutheriandD. tertiolectaby 79 and 23%, respectively.
KINETIC ANALYSIS OF INTERACTIVE EFFECTS OF CADMIUM AND NITRATE ON GROWTH OF THALASSIOSIRA FLUVIATIUS (BACILLARIOPHYCEAE)1,2
Authors: Li William K. W. 
Published: April 2006

ABSTRACT The effect of cadmium on growth rates of Thalassiosira fluviatilis Hustedt and Isochrysis galbana Parke at non‐limiting nutrient concentrations is described by the lerusalimskii equation. At limiting nitrate concentrations, the effect of Cd on growth rate of T fluviatilis is described by analogy to the general equation of enzyme inhibition in which the reaction involves a single intermediate. When cells are stressed by Cd, not only is the maximum growth rate reduced, but the half‐saturation growth parameter is increased. The value of log (k1/k2) can be used to describe the type and degree of interaction between a nutrient and an inhibitor, k, and k2ate the inhibitor concentrations resulting in 50% growth inhibition as nutrient concentration approaches zero and an infinitely large value respectively. Results show that for T fluviatilis, the degree of inhibition by Cd is more severe at low than at high NO3‐levels but the difference in seventy diminishes at Cd concentration increases.
SALINITY EFFECTS ON GROWTH AND TOXIN CONTENT OF GONYAULAX EXCAVATA. A MARINE DINOFLAGELLATE CAUSING PARALYTIC SHELLFISH POISONING1
Authors: While Alan W. 
Published: April 2006

ABSTRACT The optimum salinity for growth of Gonyaulax excavata (Braarud) Balech from Cape Ann, Massachusetts, is 30.5%o, and it grows well over a range of 20–40%o.It tolerates salinities of 11–43%o. Growth rates at 24 and 20%o are only ca. 10 and 20% less, respectively, than the maximum, 036 divisions/day. It is considered unlikely that salinity fluctuations in the coastal areas where this organism occurs significantly influence its growth rate. The paralytic toxin content in G. excavata increases with increasing salinity, up to 37%o. Therefore, the degree of toxicity of the organism in nature may be influenced by this environmental factor.
Receipt of Exercise Counseling by Older Women
Authors: Schonberg Mara A. , Marcantonio Edward R. , Wee Christina C. 
Published: April 2006

OBJECTIVES: To compare the national prevalence of reported receipt of clinician exercise counseling across four age groups of women (50–64, 65–74, 75–84, and ≥85) and to determine whether age or health are barriers to reported receipt of exercise counseling.DESIGN: 2000 National Health Interview Survey (NHIS).SETTING: United States.PARTICIPANTS: Six thousand three hundred eighty‐five women aged 50 and older who responded to the 2000 NHIS, representing an estimated 34.5 million noninstitutionalized women nationally.MEASUREMENTS: Exercise counseling, disease burden, functional dependency, and physical inactivity were assessed by questionnaire.RESULTS: Of the 6,385 women, 52.2% were aged 50 to 64, 24.8% were aged 65 to 74, 18.0% were age 75 to 84, and 5.1% were aged 85 and older. Overall, 28.3% reported that a clinician had recommended that they begin or continue to perform any type of exercise or physical activity during the previous year: 31.4% of women aged 50 to 64, 29.2% of women aged 65 to 74, 21.6% of women aged 75 to 84, and 14.4% of women aged 85 and older. Women aged 75 to 84 (adjusted odds ratio (AOR)=0.8, 95% confidence interval (CI)=0.6–1.0) and women aged 85 and older (AOR=0.6, 95% CI=0.4–0.9) were substantially less likely to report clinician counseling about exercise, before and after adjustment. Further adjustment for illness burden and functional dependency did not attenuate the effect of receipt of exercise counseling.CONCLUSION: Reported receipt of exercise counseling by older women is low nationally. Despite known benefits of late‐life exercise, women aged 75 and older are less likely to report receiving exercise counseling from their clinicians than women aged 50 to 64. Interventions should be aimed at increasing clinician counseling about exercise, especially to older women.
Use of Antibiotics in Elderly Patients with Exacerbated COPD: The OLD‐Chronic Obstructive Pulmonary Disease Study
Authors: Incalzi Raffaele Antonelli , Corsonello Andrea , Pedone Claudio , Masotti Giulio , Rengo Franco , Grassi Vittorio , Bellia Vincenzo 
Published: April 2006

OBJECTIVES: To verify how frequently geriatric patients hospitalized for exacerbated chronic obstructive pulmonary disorder (COPD) had not been given antibiotics at home and to identify the relationship between the patient's condition and the prescribing practice.DESIGN: Observational study.SETTING: General medicine acute care wards.PARTICIPANTS: Four hundred fifty‐nine elderly patients admitted to the hospital because of exacerbated COPD.MEASUREMENTS: Indices of severity of COPD exacerbation, such as age, St. George Respiratory Questionnaire (SGRQ) score, number of exacerbations in the previous year, and Cumulative Illness Rating Scale score were considered in the analyses.RESULTS: Ninety (19.6%) patients had an antibiotic prescribed before admission. The prescription was not associated with older age and was weakly associated with greater comorbidity. Having more than four exacerbations (odds ratio (OR)=2.16, 95% confidence interval (CI)=1.27–3.66) and a SGRQ symptoms subscore greater than 70 (OR=1.61, 95% CI=1.0–2.68) were independent correlates of the use of antibiotics before admission, although 67% of patients reporting more than four exacerbations in the previous year and 73.1% of patients with a SGRQ symptoms subscore greater than 70 had not been given any antibiotic prescription at home.CONCLUSION: The majority of older patients hospitalized for exacerbated COPD had not been given antibiotics at home, although they had at least one index of exacerbation severity.
In‐line filtration of autologous whole blood
Authors: Karger Ralf , Schmidt Jan , Weber Christian , Weiler‐Lorentz Arnulf , Frietsch Thomas , Kretschmer Volker 
Published: April 2006

BACKGROUND:  Experimental data suggest that autologous white blood cells (WBCs) might exert an immunomodulatory effect. Leukodepletion of autologous blood is considered to prevent this unwanted side effect of autologous transfusion. In some cases, however, prolonged filtration or filtration failures occur. Because such autologous units cannot simply be discarded, the interest was in the storage variables of autologous whole blood (AWB) units after prolonged filtration.STUDY DESIGN AND METHODS:  AWB of patients undergoing orthopedic surgery was leukodepleted before storage or left unmodified. Filtration times, volume, WBC count, hemoglobin level, hemolysis, potassium, and ATP were determined in all units with filtration times of more than 60 minutes that had not been transfused by the time of expiry and in representative samples of units that had been filtered normally or that had not been filtered.RESULTS:  In AWB filtration, the rate of prolonged filtrations or filter blockades is three to four times higher than in allogeneic whole‐blood filtration. Filtration or prolonged filtration leads to a mean loss of red blood cell (RBC) mass of 7.3 or 18.2 percent, respectively. Even in units with filtration times of more than 3 hours, storage variables were not significantly different from normally filtered or unfiltered units. Filtration times showed a high intraindividual correlation.CONCLUSION:  Leukodepletion of AWB results in a diminished preoperative deposit of RBCs that is pronounced in units with prolonged filtration. The quality of the latter suggests that it is not justified to discard AWB units with prolonged filtration times. Prolonged filtrations are related to patient characteristics that have yet to be defined.