bluuebunny/crossref_metadata_2025_split huggingface dataset:
BLUE‐GREEN ALGAE FROM BERMUDA WATERS: ECOLOGICALLY SELECTED VARIATIONS OF A SINGLE SPECIES
Authors: Sharp Jonathan H. 
Published: April 2007

SUMMARY Three strains were isolated from Bermuda waters as unialgal cultures. Although identical in cell shape, cell size, and general growth features, marked differences in pigmentation, filament length, and sheath thickness were noted. These differences are explained as being due to differences in physical conditions of the areas of isolation of the 3 strains. It is concluded that the 3 strains are ecologically selected mutants of the single species, Schizothrix calcicola.
PIT CONNECTION FORMATION IN THE RED ALGA PSEUDOGLOIOPHLOEA
Authors: Ramus J. 
Published: April 2007

SUMMARY Pit connection formation in the marine red alga Pseudogloiophloea confusa was studied with the electron microscope. The process of formation occurs in 2 stages. First, a septum forms as an annular ingrowth from the lateral walls. Lomasomes are associated with the centripetal accretion of wall material. The completed septum contains a large rimmed aperture, bounded by the continuous plasmalemma, and through which the cytoplasm is continuous from cell to cell. In the second stage, a highly structured plug is formed which completely blocks the aperture. The plug is condensed on flattened vesicles which lie parallel to one another and which traverse the aperture. The mature plug is composed of granules 50–100 A in diameter and surrounded by several dense layers which appear to enclose an 80 A limiting membrane. Once the pit connection is formed, no material is seen to traverse it.
EFFECT OF VITAMIN CONCENTRATIONS ON GROWTH AND DEVELOPMENT OF VITAMIN‐REQUIRING ALGAE1
Authors: Carlucci A. F. , Silbernagel S. B. 
Published: April 2007

SUMMARY Vitamin‐requiring marine algae, Cyclotella nana, Monochrysis lutheri, and Amphidinium carterae, were grown in batch culture with limiting concentrations of vitamin B12, thiamine, and biotin, respectively. Cell numbers, average cell volumes, biomasses, 11CO2 uptake rates, and chlorophyll a contents were determined daily. Maximum 14CO2 uptake rates in most vitamin concentrations were obtained at 2 days with C. nana and M. lutheri and at 4 days with A. carterae after starved cultures were exposed to the vitamin. Radiocarbon uptake rates approximately reflect biomass increases. Cell numbers were proportional to vitamin concentrations when cells were incubated for 2 to 3 more days. Cell sizes varied depending on time of incubation. Chlorophyll a content did not always reflect vitamin concentrations. Maximum carbon assimilation rates (Km) and saturation constants (Ks) determined from 14CO2, uptake rates in different vitamin concentrations during early incubation were higher than when determined from cell number in log phase growth. Dissolved vitamin B12, thiamine, and biotin in many samples of seawaters were in the ranges which influence the growth rate, cell size, and chlorophyll a content of C. nana, M. lutheri, and A. carterae, respectively, in laboratory studies. The effects of vitamins on these algae in situ may be similar.
ANALYSIS OF MICROTUBULE STRUCTURE IN EUGLENA GRANULATA
Authors: Arnott Howard J. , Smith Harriett E. 
Published: April 2007

SUMMARY The microtubules associated with the pellicle, reservoir and locomotory flagellum of Euglena granulata were subjected to rotational analysis using the technique of Markham et al. The results indicate that the microtubules have 11‐14 subunits when viewed in transverse section. Rotational analysis of the entire locomotory flagellum was also conducted to better demonstrate the nature of the arms extending from the peripheral microtubules.
RECOVERY OF A HOT SPRING COMMUNITY FROM A CATASTROPHE
Authors: Brock Thomas D. , Brock M. Louise 
Published: April 2007

SUMMARY The algal mats of a number of hot springs in the Lower Geyser Basin of Yellowstone National Park were destroyed by a brief violent hailstorm on August 30, 1967. The rate of recovery of the algal mat at Mushroom Spring was studied by quantitative methods. In the temperature range of 65–71 C a unicellular cyanophycean alga is the sole photosynthetic component. The doubling times during the recovery period for three stations were: Station I (71 C), 17 days; station II (68 C), 10.5 days; station III (65 C), 10 days. The algal mat had returned to apparently normal size by 152 days after the catastrophe. The significance of these observations for the conservation of hot spring communities is discussed.
NEW TAXONOMIC CRITERIA IN CLASSIFICATION OF CHLOROCOCCUM SPECIES. II. PYRENOID FINE STRUCTURE2
Authors: Brown R. Malcolm , McLean Robert J. 
Published: April 2007

SUMMARY The pyrenoids of 18 Chlorococcum species (including 3 now transferred to Tetracystis) have been investigated at the ultrastructural level. Three categories of pyrenoids were observed, including pyrenoids with unfragmented perforate starch plates in 11 species; those with many separate fragmented starch plates in 6 species; and those with hemispherical starch plates in 1 species. Pyrenoids were further distinguishable on the basis of the number of thylakoid disks or tubules which penetrate the ground substance. Stability and diversity of pyrenoid fine structure as a taxonomic criterion at the specific level have been demonstrated.
A SIMPLE TUMBLING DEVICE USED IN PREPARING ALGAL SPECIMENS FOR ELECTRON MICROSCOPY
Authors: Berlagnolli Byron L. , Nadakavukaren Mathew J. 
Published: April 2007

SUMMARYScrew cap vials are held in a wooden holder which rotates at a 90° angle to the horizontal. The. shaft of a small electric motor with built‐in gear box is attached perpendicularly to the wooden vial holder via a hole drilled in the center of the wooden holder. The rotation of the vial holder is about 6 rpm. This motion ensures a thorough tumbling of the contents of the vials. Even viscous embedding media are kept in constant agitation, which provides for superior penetration of the tissue. Tumbling devices to hold a range of vial sizes can be constructed with a minimum of labor at a cost of $10–20 each.
NOTES ON CLADOPHORA (CHLOROPHYCEAE). I. TWO NEW CARIBBEAN SPECIES CLADOPHORA JONGIORUM NOV. SP. AND CLADOPHORA LONGICELLULATA NOV. SP.
Authors: van den Hoek C. 
Published: April 2007

SUMMARY Two new Caribbean species of Cladophora are described: Cl. jongiorum from material collected on the coast of Curacao and Cl. longicellulata from specimens collected on Bermuda by various authors and wrongly identified as Cl. catenifera Kützing.
THE “HYSTRICHOSPHAERID” RESTING SPORE OF THE DINOFLAGELLATE PYRODINIUM BAHAMENSE, PLATF, 19062
Authors: Wall David , Dale Barrie 
Published: April 2007

SUMMARY Germination experiments demonstrate that the “hystrichosphere” called Hemicystodinium zoharyi, which previously has been found only as a microfossil organism, is the resting spore stage in the life history of Pyrodinium bahamense, a modern bioluminescent, thecate dinoflagellate. The morphology of this spore, together with new details of the thecal structure and ontogeny of P. bahamense, is described, and it is concluded that Pyrodinium is closely related to Gonyaulax but worthy of retention as a discrete genus. The geological history of P. bahamense is traceable to the Eocene through fossil occurrences of its spore, and it is suggested that additional pyrodinioid dinoflagellates which now are extinct were represented in Lower Tertiary seas by another hystrichosphere genus, called Homotryblium. Selected aspects of the physiology and ecology of modern dinoflagellate resting spores are discussed briefly with special reference to Pyrodinium.
ALGAE OF TWO SOMERSETSHIRE POOLS STANDING CROPS OF PHYTOPLANKTON AND EPIPELIC ALGAE AS MEASURED BY CELL NUMBERS AND CHLOROPHYLL A
Authors: Moss Brian 
Published: April 2007

SUMMARY Standing crops measured as cell numbers and as chlorophyll a content of phytoplankton and epipelic algal communities (those free‐living on sediment surfaces) in 2 small water bodies of contrasted nutrient status were measured for 27 months. Mean yearly crops, on an areal basis, of phytoplankton were 4–13.4 times greater than those of epipelic algae in the nutrient‐rich pool, but were only 0.65–1.8 times as great in the nutrient‐poor pool, which, however, was shallower than the rich pool. The role of cells < 5 μ, in diameter in the composition of standing crops was minor. Effects of phytoplankton in limiting growth of epipelic algae by light attenuation are shown. Compilation of available data shows a direct relationship between epipelic algal crops in various water bodies and nutrient‐status of the ambient water, similar to that already established for phytoplankton.
PLATYSIPHONIA DECUMBENS SP. NOV., A NEW MEMBER OF THE SARCOMENIA GROUP (RHODOPHYTA) FROM WASHINGTON
Authors: Wynne Michael J. 
Published: April 2007

SUMMARY A new species, Platysiphonia decumbens, belonging to the Sarcomenia group (Rhodophyta, Ceramiales), is described from Puget Sound, Washington. Reproductive thalli are described and illustrated, and the growth of this alga in culture is correlated with observations made on field material. The limits of the genus Platysiphonia Børgesen are broadened to include this species. The relationship of Platysiphonia to Sarcomenia Sonder is discussed.
INTERCONNECTIONS BETWEEN CYTOPLASMIC MICROTUBULES AND BASAL BODIES OF TETRASPORALEAN PSEUDOCILIA
Authors: Lembi Carole A. , Walne Patricia L. 
Published: April 2007

SUMMARY Ultrastructural investigations of the development and structure of pseudocilia in Tetraspora lubrica and Schizochlamys sp. have disclosed interconnections between cytoptasmic microtubules and pseudo‐cilial basal bodies heretofore unreported. Connections between elements of the basal bodies and the proximal connecting fibers are also described. The possible significance of the interconnections in correlating structure and function of these organelles is discussed.
NUTRITION OF PLATYDORINA CAUDATA KOFOID
Authors: Harris Denny O. 
Published: April 2007

SUMMARY The vitamins p‐aminobenzoic acid, thiamine, biotin, nicotinamide, and B12 were tested for their ability to stimulate growth. Only vitamin B12 was required. Urea and NaNO2 supported excellent growth, although sodium nitrite, ammonium nitrate, and the Casamino acids supported only fair growth. Platydorina grew aerobically in the absence of an exogenous source of carbon; however a carbon source was required for anaerobic growth. Of 25 carbon compounds examined, isocitrate supported anaerobic growth in the light equalling the aerobic controls. Growth did not occur aerobically or anaerobically in the dark with any carbon source examined. Growth was excellent at pH values in excess of 7.0. Growth at pH 10.0 was 4 times that at 7.0 in strain I.U. 850 and twice that at 7.0 in strain Kan‐3E. Growth was accelerated with the increase in temperatures but this increase may well be due to the increased intensity of light to which the cultures were exposed at the higher terperatures.
ATTRIBUTES OF CHLOROCOCCUM SPECIES: A NUMERICAL ANALYSIS2
Authors: McGuire Robert F. 
Published: April 2007

SUMMARY From previously published data, 73 characteristics of 17 species of Chlorococcum were compiled. Comparisons of character states of each character were made, and simple matching coefficients were calculated for each species by following the procedure of Sokal & Michener. From a data matrix of the matching coefficients, a phenogram was constructed according to the unweighted pair group method of Sokal & Sneath. Arithmetic averages were used in transferring data from one matrix to another. The frequency of each character state was calculated, and the character states of the highest frequency (the modes) were used to describe a “typical” Chlorococcum species. Comparisons were made between the “typical” Chlorococcum species and each of the 17 species studied. Simple matching coefficients were also calculated from these comparisons. All of the species had a relatively high affinity for the data of the calculated “typical”. Suggestions are made about the use of a “typical” taxonomic unit, and questions are raised about the taxonomic relationship among species of the genus Tetracystis and the genus Chlorococcum.
THE ULTRASTRUCTURE OF LICHENS. I. A GENERAL SURVEY
Authors: Jacobs J. B. , Ahmadjian V. 
Published: April 2007

SUMMARY The fine structure of 10 lichens was examined. A comparison was made of the storage products of the algal symbiont (Trebouxia) in situ in the desiccated and hydrated states of the lichens. All the Trebouxia phycobionts, with the exception of that in Usnea strigosa, had lipid‐containing globules in the pyrenoid. The globules were present in both the hydrated and desiccated conditions. Trebouxia in the hydrated condition contained starch granules in the chloroplast as well as the lipid‐containing globules in the pyrenoid. The cell wall of Trebouxia consists of an outer electron‐dense layer and an inner electron‐light layer. Fungal haustoria (in Lecanora rubina) rupture the outer layer of the algal cell wall and invaginate the inner layer. A thick polysaccharide fibrillar material surrounds the fungal cells. Many bacteria were observed within this material. Septa and lomasomes are described. Ellipsoidal bodies, which appear to be an integral and unique part of the lichen fungal ultrastructure, were observed associated with membrane profiles.
INFLUENCE OF TEMPERATURE AND SOLAR RADIATION ON PERSISTENCE OF VITAMIN B12, THIAMINE, AND BIOTIN IN SEAWATER1
Authors: Carlucci A. F. , Silbernagel S. B. , McNally P. M. 
Published: April 2007

SUMMARY Ecologically important concentrations of vitamin B12 and thiamine in charcoal‐treated, filter‐sterilized seawater stored in the dark at 5, 18, 28, and 37 C generally did not change over a 9‐week period, although there was some breakdown of B12 at 37 C. Biotin activity under similar conditions generally increased, indicating its decomposition to more active products. Solutions kept at–20 C had unchanged vitamin activity. B12 and biotin in seawater exposed to sunlight were rapidly destroyed. The course of thiamine destruction in sunlight indicated a breakdown to a stable, biologically active product(s)).
THE FINE STRUCTURE OF HYMENOMONAS (CRICOSPHAERA) CARTERAE. II. OBSERVATIONS ON SCALE AND COCCOLITH PRODUCTION
Authors: Pienaar Richard N. 
Published: April 2007

SUMMARY The fine structure of the marine coccolithophorid Hymenomonas (Cricosphaera) carterae (Braarud & Fagerland) Manton & Peterfi is reported. Details of the formation of the circular organic body scales are presented. Their formation is shown to be closely linked with the presence of tubules found within the Golgi cisternae. The details of coccolith production are also discussed. The formation of the organic matrix scale appears to be associated with a densely staining organelle, the intracellular coccolith pre‐cursor. The precise mechanisms involved in the mineralization of the organic matrix scale is not known but 2 possibilities are discussed. The production of coccoliths in H. carterae is compared with coccolith production in other coccolithophorids that have been investigated finestructurally.
IDENTITY OF ZOOXANTHELLAE ISOLATED FROM SOME PACIFIC TRIDACNIDAE
Authors: Taylor Dennis L. 
Published: April 2007

SUMMARY The taxonomy and nltrastructure of zooxanthellae from 6 species of Pacific giant clam have been studied from cultures. Comparison with type material shows that all of the isolates are Symbiodinium microadriaticum, a symbiotic dinoflagellate originally recorded from coelenterates in the Caribbean. Specific criteria for the identification of this organism are discussed, and their value to the comparative taxonomy of marine zooxanthellae is noted.
POLYMORPHISM IN THE DESMID XANTHIDIUM REGULARE AND ITS TAXONOMIC IMPLICATIONS
Authors: de Mattos Bicudo Carlos Eduardo , de Carvalho Lucy Mirian 
Published: April 2007

SUMMARY This paper refers to a case of polymorphism in the desmid genus Xanthidium Ehr. It is based on material from Lake Dais Irmaios, the main body of water in the Zoological and Botanical Garden in Recife, Pernambuco, northeastern Brazil, collected at 4 different times of the year during 1967 and 1968. A detailed examination of almost 1300 specimens showed an enormous variety in form of Xanthidium regulare Nordst., X. fragile Borge, and X. pseudoregulare Borge, thus allowing the authors to draw the following conclusions: (1) the name X. regulare Nordst. should be retained until further and more detailed studies on form variation within the species are available; (2) the names X. regulare Nordst. var. asteptum Nordst. in Borge, X. regulare Nordst. var. sexangulare Grönbl., X. regulare Nordst. var. sexangulare Grönbl. f. robustior Grönbl., X. fragile Borge, X. fragile Borge forma, and X. fragile Borge var. depauperatum Borge should be considered synonymous, all referring to a single variety of X. regulare Nordst., var. asteptum Nordst. in Borge emend. C. Bic. & L. M. Carv.; (3) X. pseudoregulare Borge must be treated as a variety of X. regulare Nordst. and must be called X. regulare Nordst. var. pseudoregulare (Barge) C. Bic. & L. M. Carv. Finally, a key is given to the 3 varieties of X. regulare Nordst. proposed in the present paper.
CAROTENOID INTERCONVERSION IN LIGHT‐DARK CULTURES OF THE DINOFLAGELLATE AMPHIDINIUM KLEBSII1
Authors: Mandelli Enrique F. 
Published: April 2007

SUMMARY The carotenoid pigments of Amphidinium klebsii cultures grown in LD 12:12 light regimes were determined in cells harvested during the log phase growth in the dark and light photoperiods. The analysis of the individual pigments revealed the presence of an endogenous redox carotenoid system involving the epoxide carotenoid diadinoxanthin and an unidentified carotenoid with the properties of a dihydroxy xanthophyll.
Alcohol Effects on Behavioral Control: The Impact of Likelihood and Magnitude of Negative Consequences
Authors: Corbin William R. , Cronce Jessica M. 
Published: April 2007

Background: This study utilized Signal Detection Theory to examine the relative influence of likelihood and magnitude of consequences when assessing alcohol effects on behavioral control.Methods: Moderate to heavy drinkers (N=101) were assigned to alcohol or placebo and completed 4 administrations of a go/stop task that varied the likelihood and magnitude of punishment.Results: Participants in the alcohol condition correctly responded to fewer go signals, and showed a trend toward reduction in sensitivity to task stimuli. Alcohol effects on sensitivity to go and stop signals were most evident when the likelihood of rewards and punishments were similar whereas the magnitude of punishment was not related to the strength of alcohol effects.Conclusion: Results suggest that likelihood of punishment is a more powerful determinant of alcohol‐induced disinhibition than is magnitude.
Heterogeneous Effects of Alcohol on Dopamine Release in the Striatum: A PET Study
Authors: Yoder Karmen K. , Constantinescu Cristian C. , Kareken David A. , Normandin Marc D. , Cheng Tee‐Ean , O'Connor Sean J. , Morris Evan D. 
Published: April 2007

Background:A dopaminergic response to alcohol in humans has not been demonstrated consistently with positron emission tomography (PET). We hypothesized that the effect of alcohol on striatal dopamine (DA) release may be anatomically heterogeneous between subjects. Our approach was to identify voxels that exhibited alcohol‐induced DA responses within the striatum, and to determine the relationships between DA responses and alcohol‐related behavior.Methods:A novel method was developed to examine the anatomic extent and magnitude of striatal DA responses to alcohol across subjects. Thirteen healthy control subjects underwent 2 PET scans with [11C]raclopride (1 at baseline, 1 with an IV alcohol infusion to a target breath alcohol concentration of either 60 or 80 mg%). Parametric images of striatal binding potential (BP) were used to create maps of change in BP (ΔBP, an index of changes in DA levels). The anatomic extent and magnitude of DA responses were determined with voxel extraction methods. Subjective responses (“High,”“Intoxication”) to the alcohol infusion and behavioral data from the 90‐day time‐line follow back were assessed for relationships with DA responses to alcohol.Results:A voxel‐wiset‐test between baseline and alcohol BP images did not show any differences in D2/D3receptor availability between the conditions. Data from the striatal ΔBP maps nevertheless showed that the anatomic extent and magnitude of alcohol‐induced DA release in the striatum are correlated with subjective responses to alcohol.Conclusions:The heterogeneity of dopaminergic responses to alcohol across subjects may be a reason for the lack of reports demonstrating DA involvement in alcohol‐related behaviors. By allowing for different spatial patterns of DA release within each subject's striata, we showed correlations between alcohol‐induced DA release in the striata and behavioral outcomes related to alcohol.
Serum Free Sialic Acid as a Marker of Alcohol Abuse
Authors: Chrostek Lech , Cylwik Bogdan , Korcz Walenty , Krawiec Agnieszka , Koput Alicja , Supronowicz Zbigniew , Szmitkowski Maciej 
Published: April 2007

Background: Previous studies have shown that serum total sialic acid (TSA) concentration significantly increases during alcohol abuse. Chronic ethanol consumption impairs glycosylation of many proteins. The increased desialylation rate of serum glycoproteins is one of the effects of alcohol abuse. The aim of this study was to investigate the diagnostic value of free sialic acid (FSA) as a marker of alcohol abuse.Methods: We determined serum FSA concentrations in the group of 156 alcoholic subjects and 35 healthy control subjects by means of a modification of the thiobarbituric acid method. The alcoholic group was divided into subgroups according to their history of abuse.Results: The FSA concentration was significantly higher in alcoholic subjects than in healthy controls. The subjects who consumed alcohol for longer than a week showed significantly higher FSA level than those who consumed alcohol for a shorter period. The serum FSA concentration was significantly higher in alcoholic subjects with elevated markers of liver dysfunction. The diagnostic accuracy of FSA was high, although it did not differ from TSA, and was limited by its low sensitivity.Conclusions: This study shows that FSA concentration in the sera of alcoholic subjects is increased. The low diagnostic sensitivity is accompanied by high specificity, however the accuracy is high and similar to the accuracy of TSA. Free sialic acid does not seem to be a better marker of alcohol abuse than TSA and current markers.