Search Results - (Author, Cooperation:M. Seaman)

2018-09-04

Rockefeller University Press

0022-1007

1540-9538

Medicine

Infectious Disease and Host Defense

2013-11-01

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Animals ; Antibodies, Neutralizing/*therapeutic use ; Antigens, CD4/metabolism ; Binding Sites/immunology ; HIV Antibodies/*therapeutic use ; HIV Envelope Protein gp120/immunology ; HIV-1/*immunology ; *Immunotherapy ; Macaca/immunology ; Molecular Sequence Data ; Peptide Fragments/immunology ; Simian Acquired Immunodeficiency Syndrome/prevention & control/*therapy ; Simian Immunodeficiency Virus/*physiology ; Time Factors ; Viral Load ; Viremia/*therapy

2018-06-14

The American Society for Microbiology (ASM)

0022-538X

1098-5514

Medicine

2018-03-15

The American Society for Microbiology (ASM)

0022-538X

1098-5514

Medicine

2018-09-05

The Society of Nuclear Medicine (SNM)

0022-3123

Medicine

2018-07-18

The American Society for Microbiology (ASM)

0022-538X

1098-5514

Medicine

2018-02-14

The American Society for Microbiology (ASM)

0022-538X

1098-5514

Medicine

1365-2427

Blackwell Publishing Journal Backfiles 1879-2005

Biology

SUMMARY. 1. Life table experiments were carried out in a range of turbidities on D. pulex, representing a ‘clear-water’, and on D. barbata, representing a ‘turbid-water’ species.2. In contrast to predictions based on seasonal occurrence patterns, D. pulex had a higher intrinsic rate of increase (rc)s over most of the turbidity range than D. barbata. Consistent differences in life history between the two species were found, but life history characteristics were rather insensitive to turbidity levels. Although turbidity per se appears to have little direct effect on life history parameters, it could influence the seasonal succession of these two species by interacting with other factors.3. It is suggested that visual predation by fish rather than turbidity per se probably influenced the seasonality of Daphnia species. During the warmer months, selective removal of D. pulex by visually foraging fishes may allow D. barbata to gain dominance. Effects of temperature and nutrition also merit further study.

Electronic Resource

0014-4827

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Biology

Medicine

Electronic Resource

1432-0703

Springer Online Journal Archives 1860-2000

Energy, Environment Protection, Nuclear Power Engineering

Medicine

Abstract. The toxicity of the effluent from an aluminum plant on Crassostrea gigas oyster embryogenesis (lethal effects) and larval growth (sublethal effects) was tested. Liquid and solid phases of the effluent were separately tested, and effects of mixing during exposure were also evaluated. The effluent was highly toxic, causing abnormal embryogenesis at 0.03 to 1 g l−1 and reduced growth at 0.01 to 0.3 g/l. The solid fraction was markedly more toxic than the liquid fraction. Mixing during exposure consistently increased both lethal and sublethal toxicity. Considering the trace metal content of the effluent, Hg is suspected to be primarily responsible for the toxicity, although synergistic effects of Al, Fe, and Cr cannot be discarded. Experimental evidence shows that bioavailable metal species were present not only in the liquid phase as soluble ions, but most importantly, bound to sediment particles. Based on the present data, uncontrolled disposal of aluminum plant effluent may be a major hazard to the environment, involving early life stages and recruitment in marine biota.

Electronic Resource

1432-0703

Springer Online Journal Archives 1860-2000

Energy, Environment Protection, Nuclear Power Engineering

Medicine

Abstract The toxicity of the effluent from an aluminum plant on Crassostrea gigas oyster embryogenesis (lethal effects) and larval growth (sublethal effects) was tested. Liquid and solid phases of the effluent were separately tested, and effects of mixing during exposure were also evaluated. The effluent was highly toxic, causing abnormal embryogenesis at 0.03 to 1 g 1−1 and reduced growth at 0.01 to 0.3 g/l. The solid fraction was markedly more toxic than the liquid fraction. Mixing during exposure consistently increased both lethal and sublethal toxicity. Considering the trace metal content of the effluent, Hg is suspected to be primarily responsible for the toxicity, although synergistic effects of Al, Fe, and Cr cannot be discarded. Experimental evidence shows that bioavailable metal species were present not only in the liquid phase as soluble ions, but most importantly, bound to sediment particles. Based on the present data, uncontrolled disposal of aluminum plant effluent may be a major hazard to the environment, involving early life stages and recruitment in marine biota.

Electronic Resource

1432-1793

Springer Online Journal Archives 1860-2000

Biology

Abstract Larvae of oysters, Crassostrea gigas, were maintained without food for 1 to 8 d after fertilization, and fed daily thereafter. There was little difference in survival and growth between controls and larvae kept without food for 2 or 3 d. Survival and growth rates were depressed in larvae starved for 4 or 5 d. For larvae starved for 6 to 8 d, survival was negligible or nil; even those larvae which survived the starvation period died later in the presence of food, apparently because of impaired digestion. Therefore, food availability in the first few days after spawning appears to be of paramount importance to the successful recruitment of Pacific oysters.

Electronic Resource

1573-5117

temporary water ; pans ; southern Africa ; model ; branchiopod

Springer Online Journal Archives 1860-2000

Biology

Abstract To explain the life-history strategies of temporary-water fauna, one must be able to describe the temporary habitat. It is necessary to know when it will be wet, how often this occurs, for what period each inundation lasts and what variability there is in this pattern. For logistics reasons one cannot follow each inundation in a pan for the ten years or more needed to establish a pattern. Based on the available inundation data for two seasons at Bain's Vlei Pan in a semi-arid part of South Africa, a model has been developed, using the rainfall pattern over ten years at nearby Bloemfontein, to predict inundation. Over a ten-year period preducted inundations ranged up to 87 days as a result of repeat-rain, with a mean period of 18.8 days, while a rain-episode of less than 20 mm was insufficient to inundate the pans. There was an average of 5.8 inundations per season. Single inundations do not exceed 20 days due to evaporation. When successive showers fall before periods of inundation are over, a specific extension of inundation is predictable. The precise implications of the inundation pattern on organisms requires much analysis. However, there are strong indications based on the growth, survival and pattern of egg-production among three species (Anostraca —Banchipodopsis tridens, Conchostracan —Leptestherialla inermis, and Notostracan —Triops granarius) from the pan and one species (Anostracan -Streptocephalus macrourus) from more permanent waters nearby, that the pattern of inundation is selective of the community held by the pan.

Electronic Resource

1573-5117

pans ; temporary waters ; physical chemical characteristics

Springer Online Journal Archives 1860-2000

Biology

Abstract The day-to-day fluctuations in water depth, water temperature, dissolved oxygen concentration, pH, conductivity and turbidity of six pans at Bain's Vlei, South Africa, were monitored during five successive inundations from September 1988 to April 1989. Mean duration of inundations was 13.9 days, daytime water temperatures ranged from 10.5 °C–33.1 °C, dissolved oxygen ranged from 30% to 142% saturation and conductivity ranged from 43–2630 µ S cm−1. F-test multivariate analysis indicated that physical and chemical characteristics of all pans were similar during the first inundation but differed significantly during the subsequent inundations. The aquatic pan environment is ephemeral, fluctuating and unpredictable. The biological community should consequently feature adaptations to these conditions.

Electronic Resource

1573-5117

Triops granarius ; morphology ; pans ; temporary waters ; variation

Springer Online Journal Archives 1860-2000

Biology

Abstract The morphological characteristics of a population ofTriops granarius in a system of small pans were examined during inundations of one season. Considerable variation was found in a number of characteristics. Differences in gender other than those of the reproductive organs were also significant, but diagnostic characteristics remained stable.

Electronic Resource

1573-5117

saline lakes ; athalassic ; southern Africa ; Namibia ; Botswana ; South Africa

Springer Online Journal Archives 1860-2000

Biology

Abstract Inland salt lakes are widely distributed in southern Africa: they are particularly common in South Africa, but many occur in Namibia and Botswana. All are shallow, and most are ephemeral with salinities that are not very high (mostly 〈 50 g l−1). Fringing zones of halophytes or submerged macrophytes are neither well-developed nor taxonomically diverse. The Cyanobacteria, especially Nodularia spumigena, often dominate the phytoplankton. The fauna of the Makgadikgadi area (northeast Botswana) is diverse and is similar to that of East African salt lakes. The aquatic fauna of salt water south of the Makgadikgadi Basin, on the other hand, is extremely depauperate, has no well-defined assemblage confined to saline waters, and appears mostly to comprise tolerant freshwater forms. Lovenula falcifera and Metadiaptomus transvaalensis (diaptomid copepods), Moina micrura (Cladocera) and Brachionus plicatilis (Rotifera) are frequently encountered zooplankton species, a few species of insects (Anisops sp., beetles, chironomids and ephydrids) are the principal non-planktonic macroinvertebrates. Artemia ‘salina’ is occasionally present, but may be an introduced form. The avifauna, in contrast to the aquatic macroinvertebrate fauna, is rich, with the greater and lesser flamingo often common.

Electronic Resource

1573-5117

temporary water ; tadpole shrimps ; southern Africa ; pans

Springer Online Journal Archives 1860-2000

Biology

Abstract Field sampling during successive inundations was followed by laboratory studies on growth, egg production and hatching of Triops granarius from temporary pans in southern Africa. The species was common where mean inundation was less than one month. Sexual maturity was reached in as little as six days at a carapace length of 6.5 mm. A biomass of 2.0 g, at carapace length of 25 mm was achieved in two months. Males and females occurred in similar numbers and mating was a prerequisite for sustained fertile egg production. Eggs were in similar numbers in both pouches, while successive clutches were larger. Hatching was light-dependent. Desiccation of eggs was not necessary but a period of up to 20 days was required before undesiccated eggs would hatch. In the event of desiccation, no minimum period thereof was necessary and hatching occurred within as little as a day of rehydration. Hatching success seldom exceeded 50 percent. As a candidate for aquaculture, the species has failings such as low hatching rate and cannibalism, but it grows rapidly and produces eggs over an extended period.

Electronic Resource

1573-5117

Brachionus calyciflorus ; feeding ; E. coli ; Chlorella ; sewage ponds

Springer Online Journal Archives 1860-2000

Biology

Abstract Brachionus calyciflorus (Pallas) is a common brachionid in sewage oxidation ponds. The uptake and assimilation of E. coli was optimal at concentrations of 2.7–6.9 × 108 cells ml−1 while assimilation coefficient per body weight of B. calyciflorus was found to be 10% · Ind.−1 d−1. More than two eggs per individual were produced during 24 hours when brachionids were fed with a mixutre of E. coli (109 cells · ml−1) and Chlorella spp. (106 cells · ml−1). The nutritional value of the mixture of E. coli and Chlorella spp. was found to be higher than that of bacteria alone.

Electronic Resource