ALBERT — All Library Books, journals and Electronic Records Telegrafenberg

1

Electronic Resource

Ammonium excretion by macroinvertebrates and fishes on a subtidal rocky reef in southern California (1988)

Bray, R. N. ; Miller, A. C. ; Johnson, S. ; [et al.]

Springer

Marine biology 100 (1988), S. 21-30

add to mindlist on the mindlist

Details

ISSN: 1432-1793

Source: Springer Online Journal Archives 1860-2000

Topics: Biology

Notes: Abstract Macrofauna living on subtidal rocks reefs in southern California excrete ammonium, a potentially important nutrient for benthic algae. Ammonium excretion rates of eleven macroinvertebrate and five fish taxa were determined from a total of 324 in situ incubations conducted between October 1984 and August 1985 at 14 to 17 m depths off Santa Catalina Island, California. Total ammonium excretion ranged from over 100 μmol h-1 by the kelp bass Paralabrax clathratus to less than 0.1 μmol h-1 by the gastropod Conus californicus. Weight-specific ammonium excretion generally ranged from 0.5 to 4 μmol g-1 h-1 in invertebrates and from 3 to 7 μmol g-1 h-1 in fishes. Intraspecific excretion rates varied substantially. Coefficient of variation of excretion rates were higher than reported for laboratory studies and multiple regression indicated that 50 to 90% of the variation in ammonium excretion rates of five species studied in detail could not be explained by the combined variation in dry weight, water temperature, time of day, and incubation dates. The excretion data, along with estimates of population densities and size-frequency distributions, indicate that benthic macrofauna release a total of 25 to 30 μmol NH 4 + m-2 h-1 both day and night. The species that generally make the largest contributions are a gobiid fish (Lythrypnus dalli), followed by three gastropods (Astraea undosa, Tegula eiseni, and T. aureotincta) and a sea urchin (Centrostephanus coronatus). The amount of ammonium excreted by these macrofauna on rocky reefs is insignificant compared to our previously published data on the nighttime excretion of blacksmith (Chromis punctipinnis), a pomacentrid fish that feeds in the water column during the day and shelters on the reef at night. Including blacksmiths, we estimate that the amount released by rocky-reef macrofauna at night is 〉280 μmol m-2 h-1, a rate that is similar to that for many other marine communities. Additional studies are required to determine if benthic algae utilize ammonium released by these macrofauna, especially at night.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1007/BF00392951

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

2

Electronic Resource

A link between biologically imported particulate organic nutrients and the detritus food web in reef communities (1991)

Rothans, T. C. ; Miller, A. C.

Springer

Marine biology 110 (1991), S. 145-150

add to mindlist on the mindlist

Details

ISSN: 1432-1793

Source: Springer Online Journal Archives 1860-2000

Topics: Biology

Notes: Abstract Previous work with planktivorous fishes has shown that they import particulate organic and inorganic material to reefs in the form of fecal pellets, which, in part, are deposited in crevices on the reef where these fishes shelter during their inactive period. Since these feces do not accumulate in fish shelters, we predicted that some of the feces could be rapidly consumed by reef detritivores. We examined the attractiveness of fish feces to potential reef detritivores by placing traps baited with planktivorous fish feces, along with unbaited control traps, in crevices on rocky reefs at Santa Catalina Island, California, USA, between June 1982 and November 1983, and on coral reefs at St. Croix, U.S. Virgin Islands, during June 1983. Significantly more animals (the majority being crustaceans) were trapped in the baited traps compared to the unbaited controls on both reefs. There was also a significant association between the presence of trapped animals and fish feces at Santa Catalina Island (p = 0.009); this association was not quite as strong in St. Croix (p = 0.069). The consumption by shrimp of feces marked with carmine particles and, in turn, the predation on these shrimp by a reef fish demonstrates the links between this type of imported particulate organic and inorganic material and the food web of the reef community.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1007/BF01313101

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

3

Electronic Resource

Ammonium excretion in a temperate-reef community by a planktivorous fish, Chromis punctipinnis (Pomacentridae), and potential uptake by young giant kelp, Macrocystis pyrifera (Laminariales) (1986)

Bray, R. N. ; Purcell, L. J. ; Miller, A. C.

Springer

Marine biology 90 (1986), S. 327-334

add to mindlist on the mindlist

Details

ISSN: 1432-1793

Source: Springer Online Journal Archives 1860-2000

Topics: Biology

Notes: Abstract The blacksmith Chromis punctipinnis, an abundant planktivorous damselfish off southern California, USA, shelters along rocky reefs at night. While sheltered, blacksmiths excrete ammonium that could, in turn, be utilized by nearby benthic macrophytes. Laboratory experiments during the summer and fall of 1983 and 1984 indicate that ammonium excretion at night ranged from 18.1 μmol h-1 by a 8.5 g (dry) fish, to 89.1 μmol h-1 by a 27.3 g fish; excretion rates generally declined throughout the night. Field measurements at night indicate that ammonium concentrations were significantly higher in rocky crevices occupied by blacksmiths than in unoccupied shelters, and the ammonium level in one shelter dropped after a blacksmith was experimentally removed. Young kelp plants (Macrocystis pyrifera) are capable of taking up ammonium at night. Ammonium levels in chambers containing both a blacksmith and a young kelp plant were significantly lower than in chambers containing only a fish, and ammonium levels dropped in ammoniumspiked chambers that contained kelp plants. Nighttime ammonium uptake rates by young kelp plants, which averaged 1.6 μmol g-1 (dry) h-1, were only slightly lower than those during the day. Daytime excretion by blacksmiths occasionally results in elevated ammonium levels in the water column. On two of six days, ammonium concentrations in midwater foraging aggregations were slightly but significantly higher than in upcurrent controls; since blacksmiths typically aggregate at the incurrent margin of kelp beds, the ammonium is swept downcurrent and may be utilized by large M. pyrifera that extend through the water column. Thus, the activities of blacksmiths may results in the importation of extrinsic, inorganic nitrogen to primary producers on temperate reefs.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1007/BF00428556

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

4

Electronic Resource

Thermal oxidative degradation of isotactic polypropylene catalyzed by copper and copper oxide interfaces (1979)

Jellinek, H. H. G. ; Kachi, H. ; Czanderna, A. ; [et al.]

New York : Wiley-Blackwell

Journal of Polymer Science: Polymer Chemistry Edition 17 (1979), S. 1493-1522

add to mindlist on the mindlist

Details

ISSN: 0360-6376

Keywords: Physics ; Polymer and Materials Science

Source: Wiley InterScience Backfile Collection 1832-2000

Topics: Chemistry and Pharmacology

Notes: The oxidative degradation of isotactic polypropylene films coated on well-defined Cu(Cu2O), CuO0.67, and CuO films in a temperature range of 90-120°C in a quartz-spoon-gauge-reaction vessel was studied. This catalytic reaction has been compared with the oxidation of polypropylene without copper or oxide films. The reaction vessel contained, if needed, P2O5 and/or KOH as “getters” for H2O and CO2, these substances could be menitored continuously. Cu(Cu2O) films were transformed during oxidation of the polymer to yellow CuO0.67 below 100°C and above this temperature to black CuO in the presence of H2O and CO2, whereas in the absence of these compounds CuO was formed below 100°C and CuO0.67 at 120°C. Characteristic autoxidation curves obtained in the absence of H2O and CO2 showed induction periods that were shorter for copper oxide-polymer interfaces than for glass-polymer interfaces (i.e., for uncatalyzed oxidation). Abnormalities were observed for Cu(Cu2O)-polymer interfaces because of further oxidation of Cu during the reaction. The rates of oxygen consumption were faster for CuO0.67-polymer and CuO-polymer than for the uncatalyzed reaction; the catalytic action of CuO0.67 was somewhat larger than that of CuO. The important observation was made that the mechanism of oxidation is not the same in the absence and presence of reaction products; that is, H2O and CO2. This was confirmed by ion beam scattering experiments, which also revealed that an oxidation-reduction process takes place at Cu and their oxide interfaces. A mechanism for the catalytic oxidation process, based on the ease by which copper ions are released from the metal oxides at the interface, was formulated. These ions diffuse subsequently as actions of carboxylate anions into the bulk of the polymer. Arrhenius equations of oxygen consumption are given for all cases; the energy of activation calculated for the initiation of the uncatalyzed oxidation agrees with its literature value. The energy of activation for the initiation of the catalyzed reaction was a few kilocalories lower than that for the uncatalyzed reaction. Catalytic action is mainly operative for the initiation reaction at the interface and for the decomposition of hydroperoxides by copper ions. Preventing the delivery of copper ions to the polymer would be the most efficient way of inhibiting the catalysis.

Additional Material: 29 Ill.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1002/pol.1979.170170523

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

5

Electronic Resource

Results of an ISS round robin sponsored by ASTM committee E-42 on surface analysis (1986)

Miller, A. C.

Chichester [u.a.] : Wiley-Blackwell

Surface and Interface Analysis 8 (1986), S. 47-51

add to mindlist on the mindlist

Details

ISSN: 0142-2421

Keywords: Chemistry ; Polymer and Materials Science

Source: Wiley InterScience Backfile Collection 1832-2000

Topics: Physics

Notes: Results are reported for a round robin involving ion scattering peak positions and FWHM measurements from seven cylindrical mirror analyzer (CMA) based instruments from the same manufacturer. The specimen used in the round robin was a Cu-Ag-Au ternary alloy. The ion scattering data were obtained using 4He and 20Ne ions at 1 and 2 keV. Within the set of data for any given peak, the spread in the FWHM values was 〉70%, and the variation between the maximum and minimum CMA voltages was ∼8.5% A comparison of the experimental data with the results of calculations involving the dispersion characteristics of a CMA and the scattering equation suggests that much of the spread in the peak position is associated with the position of the specimen with respect to the CMA geometry. The cause of the spread in the FWHM measurements is unknown. Further analysis of the data indicates an inelastic energy loss of ∼3% for 20Ne scattering from Ag at 2 keV.

Additional Material: 2 Ill.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1002/sia.740080202

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

6

Electronic Resource

Energy calibration of X-ray photoelectron spectrometers. Part III: Location of the zero point on the binding-energy scale (1998)

Miller, A. C. ; Powell, C. J. ; Gelius, U. ; [et al.]

Chichester [u.a.] : Wiley-Blackwell

Surface and Interface Analysis 26 (1998), S. 606-614

add to mindlist on the mindlist

Details

ISSN: 0142-2421

Keywords: XPS ; x-ray photoelectron spectroscopy ; calibration ; Fermi energy ; Chemistry ; Polymer and Materials Science

Source: Wiley InterScience Backfile Collection 1832-2000

Topics: Physics

Notes: Calibration of the binding energy scale in x-ray photoelectron spectroscopy (XPS) requires location of the zero point. This zero point has previously been identified with the inflection point in the Fermi-edge region of a valence-band photoemission spectrum of nickel. Comparison of photoemission spectra of nickel and silver measured with monochromated x-rays shows that the inflection points near the Fermi edge differ by 45±5 meV (where the stated uncertainty indicates the standard uncertainty) at an instrumental energy resolution of 0.30 eV. This difference is due to differences in the valence-band densities of states (DOS) of the two metals. Simulations of the Ni photoemission spectrum have been performed based on the DOS calculated by Eckhardt and Fritsche, and the simulated spectrum agrees well with the measured spectrum in the near-edge region. Additional simulations of the Ni photoemission spectrum have been carried out with both monochromated Al x-rays and unmonochromated Mg and Al characteristic x-rays to determine how the Ni near-edge inflection point varies with the energy resolution of the electron energy analyzer in XPS. © 1998 John Wiley & Sons, Ltd.

Additional Material: 9 Ill.

Type of Medium: Electronic Resource

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

7

Electronic Resource

XPS Characterization of In situ Prepared Ti/Glass Interfaces (1996)

Saha, S. K. ; Jain, H. ; Miller, A. C. ; [et al.]

Chichester [u.a.] : Wiley-Blackwell

Surface and Interface Analysis 24 (1996), S. 113-118

add to mindlist on the mindlist

Details

ISSN: 0142-2421

Keywords: Chemistry ; Polymer and Materials Science

Source: Wiley InterScience Backfile Collection 1832-2000

Topics: Physics

Notes: Aninsitu method is described for studying the reactions between thin titanium films and SiO2 or Na2O · 2SiO2 glasses. It involves fracturing the glass under ultrahigh vacuum conditions, depositing titanium thin films on the fractured surfaces and then characterizing interface reactions using x-ray photoelectron spectroscopy (XPS); the whole process is carried out without interrupting the ultrahigh vacuum. Owing to the extremely clean interface formed by this method, titanium silicide forms in both glass systems, even at room temperature. However, for glass surfaces that have been chemically cleaned in air, silicide formation is suppressed because carbon species from contamination at the interface consume the titanium film. The superiority of theinsitu method to investigate thin film reactions is thus established.

Additional Material: 12 Ill.

Type of Medium: Electronic Resource

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

8

Unknown

Rescue of neurodegeneration in the Fig4 null mouse by a catalytically inactive FIG4 transgene (2016)

Lenk, G. M., Frei, C. M., Miller, A. C., Wallen, R. C., Mironova, Y. A., Giger, R. J., Meisler, M. H.

Oxford University Press

In: Human Molecular Genetics

add to mindlist on the mindlist

Details

Publication Date: 2016-01-09

Description: The lipid phosphatase FIG4 is a subunit of the protein complex that regulates biosynthesis of the signaling lipid PI(3,5)P 2 . Mutations of FIG4 result in juvenile lethality and spongiform neurodegeneration in the mouse, and are responsible for the human disorders Charcot–Marie–Tooth disease, Yunis–Varon syndrome and polymicrogyria with seizures. We previously demonstrated that conditional expression of a wild-type FIG4 transgene in neurons is sufficient to rescue most of the abnormalities of Fig4 null mice, including juvenile lethality and extensive neurodegeneration. To evaluate the contribution of the phosphatase activity to the in vivo function of Fig4 , we introduced the mutation p.Cys486Ser into the Sac phosphatase active-site motif CX 5 RT. Transfection of the Fig4 Cys486Ser cDNA into cultured Fig4 –/– fibroblasts was effective in preventing vacuolization. The neuronal expression of an NSE- Fig4 Cys486Ser transgene in vivo prevented the neonatal neurodegeneration and juvenile lethality seen in Fig4 null mice. These observations demonstrate that the catalytically inactive FIG4 protein provides significant function, possibly by stabilization of the PI(3,5)P 2 biosynthetic complex and/or localization of the complex to endolysosomal vesicles. Despite this partial rescue, later in life the NSE- Fig4 Cys486Ser transgenic mice display significant abnormalities that include hydrocephalus, defective myelination and reduced lifespan. The late onset phenotype of the NSE- Fig4 Cys486Ser transgenic mice demonstrates that the phosphatase activity of FIG4 has an essential role in vivo .

Print ISSN: 0964-6906

Electronic ISSN: 1460-2083

Topics: Biology , Medicine