bluuebunny/crossref_metadata_2025 huggingface dataset:
Septate‐tubular textures in 2.0‐Ga pillow lavas from the Pechenga Greenstone Belt: a nano‐spectroscopic approach to investigate their biogenicity
Authors: FLIEGEL D. , WIRTH R. , SIMONETTI A. , FURNES H. , STAUDIGEL H. , HANSKI E. , MUEHLENBACHS K.
Published: August 2010

Pillow lava rims and interpillow hyaloclastites from the upper part of the Pechenga Greenstone Belt, Kola Peninsula, N‐Russia contain rare tubular textures 15–20 μm in diameter and up to several hundred μm long in prehnite–pumpellyite to lower greenschist facies meta‐volcanic glass. The textures are septate with regular compartments 5–20 μm across and exhibit branching, stopping and no intersecting features. Synchrotron micro‐energy dispersive X‐ray was used to image elemental distributions; scanning transmission X‐ray microscopy, Fe L‐edge and C K‐edge were used to identify iron and carbon speciation at interfaces between the tubular textures and the host rock. In situ U–Pb radiometric dating by LA‐MC‐ICP‐MS (laser ablation multicollector inductively coupled plasma mass spectrometry) of titanite from pillow lavas yielded a metamorphic age of 1790 ± 89 Ma. Focused ion‐beam milling combined with transmission electron microscopy was used to analyze the textures in three dimensions. Electron diffraction showed that the textures are mineralized by orientated pumpellyite. On the margins of the tubes, an interface between mica or chlorite and the pumpellyite shows evidence of dissolution reactions where the pumpellyite is replaced by mica/chlorite. A thin poorly crystalline Fe‐phase, probably precipitated out of solution, occurs at the interface between pumpellyite and mica/chlorite. This sequence of phases leads to the hypothesis that the tubes were initially hollow, compartmentalized structures in volcanic glass that were mineralized by pumpellyite during low‐grade metamorphism. Later, a Fe‐bearing fluid mineralized the compartments between the pumpellyite and lastly the pumpellyite was partially dissolved and replaced by chlorite during greenschist metamorphism. The most plausible origin for a septate‐tubular texture is a progressive etching of the host matrix by several generations of microbes and subsequently these tubes were filled by authigenic mineral precipitates. This preserves the textures in the rock record over geological time. The micro textures reported here thus represent a pumpellyite‐mineralized trace fossil that records a Paleoproterozoic sub‐seafloor biosphere.
Influence of age on the multifocal electroretinography
Authors: Mohidin N. , Yap M. K. H. , Jacobs R. J.
Published: August 2010

The influence of age on the amplitude density (nV/sq deg) of the multifocal electroretinogram (ERG) was studied in 90 healthy subjects aged 18–52 years. Subjects were divided into three separate age groups; (i) 18–22 years (ii) 33‐37 years and (iii) 48–52 years. Amplitude density of first order kernel of the multifocal ERG was measured for the three different age groups. When the whole response of the retina is considered, analysis of variance showed no significant differences in amplitude density between the three age groups. (ANOVA, df: 2, 87 F=2.29, p=0.11. However if the responses were segregated into a central area and concentric rings around the central area, analysis of variance showed that there were significant differences in responses between rings at different eccentricities and between different age groups (Anova F=76.19, df: 17, 522, p=0.00001). Post hoc analysis showed that the responses from the centre and the second ring around the centre of fixation for 48–52 year olds were significantly lower than those responses from the 33–37 year old and the 18–22 year old age groups. The decline in the multifocal ERG in the central retina of the 48–52 year olds could be associated with the decline of the number of photoreceptors as the eye ages. Student t test revealed no significant differences in amplitude density between males and females.
Decision support systems based on the Life Cycle Inventory for Municipal Solid Waste management under uncertainty
Authors: Bieda Boguslaw , Tadeusiewicz Ryszard
Published: August 2010

Life Cycle Inventory (LCI) – part of a Life Cycle Assessment (LCA) method – was used to evaluate two scenarios for waste to energy gasification plants based on the American (design at 200 T/D) and Australian (design at 240 T/D) gasification technologies including a 15‐year income statement projection. The paper uses stochastic modeling based on the internal rate of return (IRR) and net present value (NPV) values of the new and actual equipment. The Monte Carlo simulation with the Excel spreadsheet and Crystal Ball® software was used to develop scenarios for uncertainty inputs. The sensitivity analysis and frequency charts represent the Crystal Ball® output and simulation results.
Managerial Ownership and Accounting Conservatism
Authors: LAFOND RYAN , ROYCHOWDHURY SUGATA
Published: August 2010

In this paper we examine the effect of managerial ownership on financial reporting conservatism. Separation of ownership and control gives rise to agency problems between managers and shareholders. Financial reporting conservatism is one potential mechanism to address these agency problems. We hypothesize that, as managerial ownership declines, the severity of agency problem increases, increasing the demand for conservatism. Consistent with our hypothesis, we find that conservatism as measured by the asymmetric timeliness of earnings declines with managerial ownership. The negative association between managerial ownership and asymmetric timeliness of earnings is robust to various controls, in particular, for the investment opportunity set. We thus provide evidence of a demand for conservatism from the firm's shareholders.
KINETICS OF CHLOROPHYLL a AND PLASTOQUINONE A: CHANGES IN RESPONSE TO LIGHT INTENSITY1
Authors: Sheridan R. P.
Published: August 2010

The thermophilic blue‐green Synechococcus lividus Y52 was grown at several light intensities between 200 and 2400 ft‐c. A 3.4‐fold change of cellular chlorophyll (Chl) a content was found. The concentration of Plastoquinone A (PQA) per Chl a varied by a factor of 7, whereas PQA per cell varied by 1.4. Adaptation to light intensity appeared to occur through changes in size of the light‐gathering antenna of chlorophyll and phycocyanin while the concentration of PQA remained nearly constant.
OSCILLATORIA (TRICHODESMIUM) THIEBAUTII (CYANOPHYTA) IN THE CENTRAL NORTH ATLANTIC OCEAN12
Authors: McCarthy James J. , Carpenter Edward J.
Published: August 2010

Physiological rate measurements were made with Oscillatoria thiebautii (Gom.) Geitler in the subtropical north Atlantic Ocean between Spain and Bermuda during May and June of 1975. The near surface C:N fixation ratios averaged 6.5, and the cellular composition ratio was 6.2, suggesting that N2 fixation is the major path of nitrogenous nutrition for this alga. Compared to other oceanic phytoplankters, it has a low affinity for orthophosphate at oceanic concentrations (ks= 9.0); however, it has a high potential for utilizing phosphomonoesters (170–300 ng atoms P ·μg chl a−1· h−1). Maximal photosynthesis occurred at 450–700 μ Einstein · m−2· s−1, and was inhibited by full sunlight. Calculated cell division rates (ca. 180 days) suggest that relative to other phytoplankters in this oceanic region, O. thiebautii must be subjected to negligible grazing pressure. No major differences in C, N, chl a or ATP were observed between the tuft (fusiform) and puff (spherical) colonies. ATP concentrations relative to other cellular constituents varied greatly between colonies, suggesting a general inter‐colony physiological variability in the open Atlantic. With increasing depth in the euphotic zone, there was no evidence for chromatic adaption. The observations that O. thiebautii represents only a small fraction of total phytoplankton biomass and that its growth rate is 10–100 times slower than that of the other indigenous phytoplankton, strongly suggest that N2 fixation by this alga is a virtually insignificant component of the nitrogenous nutrition for the phytoplankton of the North Atlantic central gyre in late Spring.
AQUIL: A CHEMICALLY DEFINED PHYTOPLANKTON CULTURE MEDIUM FOR TRACE METAL STUDIES12
Authors: Morel F. M. M. , Rueter J. G. , Anderson Donald M. , Guillard R. R. L.
Published: August 2010

The medium Aquil and its variations have been successfully used for trace metal studies of marine phytoplankton (diatoms and dinoflagellates) over the past three years. Here, the recipes, the methods of preparation and the chemical composition of Aquil are presented in detail. To permit complete definition of chemical speciation of the various components as calculated from thermodynamic equilibria, trace element contamination is controlled and the formation of precipitates and adsorbates is avoided. It is established that Aquil is suitable for physiological experiments with a variety of marine phytoplankters representing all major phyla. Modifications of the basic recipe and design of chemically defined media in general are discussed.
TAXONOMY AND FRUSTULAR STRUCTURE OF THE MARINE CENTRIC DIATOM PARALIA SULCATA1
Authors: Crawford Richard M.
Published: August 2010

Light and electron microscopy were used to investigate the complex structure of the frustule of Paralia sulcata (Ehrenb.) Cleve. Rimoportulae are reported for the first time in this diatom and two types of linking processes are described. The ease with which the cingulum is lost is explained with regard to its attachment to the valve. Two kinds of heterovalvy were observed and the taxonomic significance of one of these is discussed. The validity of Heiberg's genus Paralia is confirmed and a type slide of the species is designated.
FACTORS REGULATING THE SPATIAL DISTRIBUTION OF THE FILAMENTOUS ALGA PITHOPHORA OEDOGONIA (CHLOROPHYCEAE) IN AN INDIANA LAKE1
Authors: Spencer David F. , Lembi Carole A.
Published: August 2010

Pithophora oedogonia (Mont.) Wittr. biomass in Surrey Lake, Indiana was greater in the littoral than in the pelagial region. Although mean soluble reactive phosphorus concentrations did not differ between the two areas, nitrate concentrations were almost six times higher in the cove than in the open water. Using laboratory cultures of Pithophora, the half saturation constant (Ks at 20° C relating filament growth to external concentrations of nitrate‐nitrogen was determined to be 1.23 mg L−1 (=88 μM)and for phosphate‐phosphorus, 0.1 mg L−1 (=3.22 μM). These values were used to calculate a NO3‐N/PO4‐P atomic ratio of 27.6. Comparison of this value with NO3‐N/PO4‐P ratios in Surrey Lake showed that nitrogen limiting conditions were prevalent in the open water section of the lake. Alkaline phosphatase and dark ammonia uptake analyses on field collected filaments from the shallow and deep water sections confirmed the hypothesis that nitrate is the major factor limiting growth of Pithophora in Surrey Lake.
PHYTOPLANKTON LIPIDS: INTERSPECIFIC DIFFERENCES AND EFFECTS OF NITRATE, SILICATE AND LIGHT‐DARK CYCLES1
Authors: Shifrin Neil S. , Chisholm Sallie W.
Published: August 2010

The lipid content of various phytoplankton species was measured in response to nitrogen and silicon limitation and over the cell cycle in synchronized cultures. In a survey of 30 species it was found that during log‐phase growth, green algae contained an average of 17.1% total lipids (% of total dry weight), whereas diatoms contained an average of 24.5%. Nitrogen deprivation for 4 to 9 days resulted in 2‐ to 3‐fold increases in the lipid content of green algae, whereas both increases and decreases were noted in diatoms, depending on the species. The greatest lipid content measured in the study was 72% in Monallantus salina (strain GSB Sticho) which had been deprived of nitrogen for 9 days. Nitrate replenishment in a nitrogen starved culture of Oocystis polymorpha Groover & Bold showed that the excess cellular lipids do not rapidly disappear during recovery, until cell division occurs.

A silicate deprivation experiment with Cyclotella cryptica Reimann, Lewin & Guillard (strain 7c) showed an increase in the total cellular lipid fraction from. 30 to 42% of dry weight within 6 h of the onset of silicon limitation, while the mass of lipid material per cell doubled within 12 h. The total lipid fraction in O. polymorpha was found to remain constant over the cell cycle in synchronized cultures regardless of the light regime. The data presented provided the first internally consistent study of phytoplankton lipids for a wide range of species and several growth conditions.
THE MECHANISMS OF FLUORIDE TOXICITY AND FLUORIDE RESISTANCE IN SYNECHOCOCCUS LEOPOLIENSIS (CYANOPHYCEAE)1
Authors: Nichol Brian E. , Budd Kenneth , Palmer Gerald R. , MacArthur J. Duncan
Published: August 2010

Fluoride was supplied as dissolved NaF at concentrations ranging from 0.26 to 7.9 mM (5–150 ppm) to three freshwater microalgae: Synechococcus leopoliensis (Racib.) Komarek (Cyanophyta), Oscillatoria limnetica Lemmermann (Cyanophyta) and Chlorella pyrenoidosa Chick (Chlorophyta). Growth of C. pyrenoidosa was unaffected by fluoride, and uptake of fluoride by this organism was not detectable. Growth of the cyanophytes was temporarily inhibited by NaF. The duration of this growth lag increased markedly as the pH was lowered at constant external fluoride concentration. In S. leopoliensis, fluoride uptake and inhibition of photosynthesis by NaF increased in the same way as did the growth lag in response to pH. Growth‐inhibitory NaF treatments decreased the ATP level in cells of S. leopoliensis by 75% and also abolished phosphate uptake. Cells of S. leopoliensis in which fluoride‐resistance was induced by prior growth in non‐growth‐inhibitory levels of NaF accumulated much less fluoride than did normal (“sensitive”) cells, and also did not respond to fluride by reduction of the ATP pool. It is suggested (1) that fluoride enters sensitive cells of S. leopoliensis principally as undissociated HF; (2) that its major inhibitory effect in these cells is the reduction in cellular ATP; (3)that fluoride‐resistant cells accumulate less fluoride by developing incresed permeability to the fluoride anion.
PHOTOSYNTHETIC CARBON METABOLISM IN ENTEROMORPHA COMPRESSA (CHLOROPHYTA)1
Authors: Beer Sven , Shragge Bryan
Published: August 2010

The intertidal macroalga Enteromorpha compressa showed the ability to use HCO3− as an exogenous inorganic carbon (Ci) source for photosynthesis. However, although the natural seawater concentration of this carbon form was saturating, additional CO2 above ambient Ci levels doubled net photosynthetic rates. Therefore, the productivity of this alga, when submerged, is likely to be limited by Ci. When plants were exposed to air, photosynthetic rates saturated at air‐levels of CO2 during mild desiccation.

Based on carbon fixing enzyme activities and Ci pulsechase incorporation patterns, it was found that Enteromorpha is a C3 plant. However, this alga did not show O2 inhibited photosynthetic rates at natural seawater Ci conditions. It is suggested that such a C4‐ like gas exchange response is due to the HCO3− utilization system concentrating CO2 intracellularly, thus alleviating apparent photorespiration.
MEDIA FOR THE CULTURE OF OCEANIC ULTRAPHYTOPLANKTON1,2
Authors: Keller Maureen D. , Selvin Rhonda C. , Claus Wolfgang , Guillard Robert R. L.
Published: August 2010

A medium (K) developed for culturing fastidious oceanic phytoplankton has been tested using recently isolated ultraphytoplankton clones representing at least seven different algal classes. The medium was designed to satisfy as completely as possible the nutritional requirements of this diverse group of phytoplankters. Important aspects are the addition of selenium, the inclusion of both nitrate and ammonium, an increased level of chelation and a moderate level of pH buffering. The seawater‐based version of this medium has been tested on 200 clones of which 186 grew reliably. A synthetic counterpart (AK) was tested on 40 of the more difficult clones and 27 grew well; 13 grew not all. While neither medium meets the exacting nutritional needs of all the ultraphytoplankton forms tested, they are excellent for most oceanic clones and are very successful for the isolation and establishment in culture of new oceanic phytoplankton clones.
SPECIES OF ANTITHAMNION (RHODOPHYCEAE, CERAMIACEAE) OCCURRING ON THE SOUTHEAST AFRICAN COAST (NATAL)1
Authors: Norris Richard E.
Published: August 2010

Three species of Antithamnion Naegeli were previously known from Natal, all reported since 1984. A more thorough collection of the flora in recent months has revealed that there are nine species in Natal, four of which are newly described. Vegetative characteristics are emphasized in this study of the taxonomy of Antithamnion, the most important being (1) size of axial cells, (2) form of whorl‐branchlets, (3) size of whorl‐branchlet basal cells, (4) size and shape of whorl‐branchlet terminal cells, (5) size and position of gland cells, (6) primary or secondary derivation of indeterminate lateral branches, and (7) the relationship of primary indeterminate branches, if present, to normal arrangement of whorl‐branchlets. Two closely related species, A. diminuatum Wollaston and A. eliseae sp. nov. have been grown in laboratory culture allowing for testing of stability and reliability of vegetative characteristics for use in taxonomic studies. Conclusions are that these criteria can be effectively used for these purposes. In addition to A. eliseae, A. nematocladellum, A. pterocladellum and A. adenocladellum also are described as new species. A tropical species previously known from the Caribbean and Red Seas, A. lherminieri Nasr, a species previously recorded from Japan, A. secundum Itono, a species previously known from California and Japan, A hubbsii Dawson, and two species from Australia, A. diminuatum Wollaston and A. divergens (J. Agardh) J. Agardh, are also described from Natal.
QUANTITATIVE GENETIC ANALYSIS OF MORPHOLOGICAL VARIATION IN AN ANTARCTIC DIATOM GROWN AT TWO LIGHT INTENSITIES1
Authors: Wood A. Michelle , Lande Russell , Fryxell Greta A.
Published: August 2010

Ten clonal isolates of Thalassiosira tumida (Janisch) Hasle were grown in duplicate semi‐continuous batch cultures at 116 and 11.6 μE.m−2.s−1; acclimated cells were harvested during exponential growth and cleaned for examination by light microscopy (LM) and scanning electron microscopy (SEM). Number of strutted processes surrounding the central annulus (SP) and average number of satellite pores per process (AVSAT) were counted using SEM on 20 valves from each culture grown in high light, for a total of 400 valves examined; number of marginal labiate processes (LP) and overall diameter (DIAM) were measured using LM on 20 valves from each culture grown in both high and low light for a total of 800 valves examined. Univariate analysis of variance showed that bottle effects resulting from microenvironmental differences between replicates were a small but significant source of variation in DIAM, LP, and SP but not AVSAT. Significant differences among clones were observed for all characters. Decreased irradiance resulted in a significant decrease in valve diameter but no significant effect on LP; no light x clone interaction was obsered. Significant covariance between characters among clones was also observed; since valve diameter is known to decrease during asexual growth, the correlation coefficients for SP, AVSAT, and LP with DIAM were used to correct the data for this source of nongenetic differences between clones. Analysis of the size‐corrected data showed that the proportion of total phenotypic variance in SP, LP, and AVSAT caused by genetic differences among clones was 0.14, 0.14, and 0.30, respectively. This indicates that the majority of total phenotypic variance was due to environmental or developmental causes, but that sufficient genetic variability exists to support rapid phenotypic evolution in SP, LP, and AVSAT under continued directional selection. Finally, the results of the genetic analysis revealed a high (0.82) genetic correlation between SP and LP.
31P NUCLEAR MAGNETIC RESONANCE STUDY OF INTRACELLULAR PHOSPHATE POOLS AND POLYPHOSPHATE METABOLISM IN HETEROSIGMA AKASHIWO (HADA) HADA (RAPHIDOPHYCEAE)1
Authors: Watanabe Masataka , Kohata Kunio , Kunugi Masayuki
Published: August 2010

The effects of starvation and subsequent addition of phosphate‐containing medium on the phosphate metabolic intermediates were studied by 31P‐NMR spectroscopy of perchloric acid extracts and intact cells of Heterosigma akashiwo (Hada) hada. When orthophosphate in the medium was completely depleted the medium was enriched with orthophosphate (4.5 μM). In the phosphate starved condition, the P cell quota was 76 fmol‐cell−1 and the major components of phosphate intermediates were phosphodiester, sugar phosphate and orthophosphate (Pi) After addition of Pi' rapid uptake of Pi was observed and the P cell quota increased to 108 fmol. cell−1 in 2 h, 134 fmol. cell−1 in 5 h and 222 fmol. cell−1 in 1 day after addition of phosphate. The 31P‐NMR spectrum indicated that a major portion of P was stored as polyphosphate, in which the average chain length of polyphosphate increased from 10 to 20 phosphate residues in one day after addition of Pi‐
OBSERVATIONS OF A TUBE‐DWELLING DIATOM: NAVICULA HAMULIFERA (BACILLARIOPHYCEAE)1
Authors: Navarro J. Nelson
Published: August 2010

Colonies of the tube‐dwelling diatom Navicula hamulifera Grunow living on mangrove prop roots in Indian River, Florida and at La Parguera, Puerto Rico, were studied using light and electron microscopy. Observations of the tube morphology and cell structure of this diatom from fresh samples and cultures are described, as well as the ultrastructural morphology of its frustule.

The formation of tubes by this diatom is reported for the first time. Comparisons are made with the closest species; Navicula delognei V.H. and Navicula pseudoco moides Hendey.
PATTERNS OF RELATIVE GROWTH IN NEREOCYSTIS LUETKEANA (PHAEOPHYTA)1
Authors: Kain (Jones) Joanna M.
Published: August 2010

Plants of Nereocystis luetkeana (Mert.) Post. et Rupr. of different sizes were held on a raft at the surface of the sea, off the Friday Harbor Laboratories, San Juan Island, Washington for 5‐day periods for obseruation of detailed relative growth of different parts. Each stipe was marked at intenlals with injected Indian ink and each blade was punched with a series of holes. Measurements of diameter, length, width and thickness were made before and after the 5‐day periods.

Blades showed a very similar pattern of relative growth rate (R) ovler an 18‐fold range of sizes. The maximum local R in length was about 0.2 day−1 and occurred at 6.5% of the distance from the bulb to the tip, declining to 0.01 at half way. Half the linear growth occurred in the proximal one tenth of the blade and 95% within the proximal half: The relative growth rate of the whole blade declined only slightly with increased size and lay between 0.03 and 0.06 day−1 (approx. 3‐6% day−1). The linear growth rate therefore increased with blade size, the maximum observed being 14 cm day−1. The maximum relative growth rate in blade width was slower, and sited more distally than that in length. Unless fertile tissue was involved all blade tissue, except that closely adjoining the bulb, became thinner duringgrowth. R in volume reached 0.3 day−1.

Presumably because the plants were held near the sea surface stipes grew slowly, with a maximum linear rate of 9 mm day−1. The maximum R in length decreased with stipe length. Bulb R in volume also decreased as size increased, from a maximum of 0.3 day−1.
COMPARATIVE ULTRASTRUCTURE OF THREE SPECIES OF CHLOROSARCINA (CHLOROSARCINACEAE, CHLOROPHYTA)1,2
Authors: Deason Temd R. , Floyd Gary L.
Published: August 2010

Ultrastructural studies revealed that Chlorosarcina stigmatica Deason differs from C. brevispinosa and C. longispinosa Chantanachat and Bold because the vegetative cells possess a pyrenoid, and the zoospores have chlorophycean characteristics. Zoospores of the latter species exhibit pleurastrophycean characteristics including counterclockwise absolute orientation of the flagellar apparatus components. Nuclear division in C. longispinosa, like that of Friedmannia israelensis Chantanachat and Bold, is metacentric. It is suggested that a new genus, Desmotetra, be erected for Chlorosarcina stigmatica, and that it, along with Chlorosarcinopsis Herndon, be placed in the Chlorococcales, Chlorophyceae. Chlorosarcina brevispinosa and C. longispinosa belong in the Pleurastrales, Pleurastrophyceae.
ETIOLOGY AND DEVELOPMENT OF HYPERPLASIA INDUCED BY STREBLONEMA SP. (PHAEOPHYTA) ON MEMBERS OF THE LAMINARIALES (PHAEOPHYTA)1
Authors: Apt Kirk E.
Published: August 2010

Filaments of Streblonema sp. isolated from hyperplasia (galls) on Nereocystis luetkeana (Mert.) Post. et Rupr. induced similar gall growths when inoculated on young sporophytes of Nereocystis luetkeana, Macrocystis integrifolia Bory, and Laminaria japonica Aresch. Filaments were irregularly branched and uniseriate with cells 5–8 μm in diameter and 10–30 μm long. Growth under varied cultured conditions produced unilocular sporangia. Zoospores released from the sporangia germinated into identical filaments which also formed unilocular sporangia. Gall tissue originated from the innermost cells of the epidermal meristematic zone. When infected these cells divided in an irregular and unorganized manner. The resulting structure was a pronounced departure from normal morphology.
OCCURRENCE OF AN ISOPRENOID C25 DIUNASATURATED ALKENE AND HIGH NEUTRAL LIPID CONTENT IN ANTRACTIC SEA‐ICE DIATOM COMMUNITIES1
Authors: Nichols Peter D. , Palmisano Anna C. , Volkman John K. , Smith Glen A. , White David C.
Published: August 2010

The lipid and hydrocarbon composition of natural populations of diatom communities collected during the austral spring bloom of 1985 in the sea‐ice at McMurdo Sound, Antartica was analyzed by TLC‐FID, GC and GC‐MS. Sea‐ice diatom communities were dominated by Amphiprora sp., Nitzschia stellata Manguin and Berkeleya sp. at Cape Armitage; N. stellata, Amphiprora, Pleurosigma, N. kerguelensis (O'Meara) Hasle and some small centric diatoms adjacent to the Erebus Ice Tongue; and Porosira pseudodenticulata (Hustedt) Jouse at Wohlschlag Bay. Lipid distributions of the sea ice diatom communities from the Cape Armitage and Ereus sites were characterized by high concentrations of tracylaglecycerol (triacylglycerolplar lipid = 1.0 to 1.5). The hydrocarbon n‐C21:6, common in temperate diatoms, and an isoprenoid C25 diunsaturated alkene were the dominant hydrocarons detected at these two sites. Hydrogenation of the C25 diene produced the known alkane 2, 6, 10, 14‐tetramethyl‐7‐ (3‐methylpentyl)‐pentadecane. The C25 diene is one of several structurally related hydrocarbons reported in many estuarine, coastal and ocean ic sediments. We propose that certain species of diatoms are a likely source of these alkenes in sediments. The first reported biological occurrence of the C25 diene in the green seaweed Enteromorpha prolifera may have been due to the presence of epiphytic microalgae in the field sample analysed.
RIMOPORTULAE IN EUPODISCUS RADIATUS (BACILLARIOPHYCEAE) FROM THE NORTHEASTERN GULF OF MEXICO1
Authors: K. Prasad Akshinthala K. S. , Nienow James A.
Published: August 2010

Specimens of Eupodiscus radiatus Bailey from the northeastern Gulf of Mexico were examined with light and scanning electron microscopy. In contrast to previous studies of this taxon, we report the presence of two, rarely one, rimoportulae (labiate processes) between consecutive ocelli. This finding changes our understanding of the phylogenetic relationships in the family Eupodiscaceae.
The Hydration Behavior of Ca–P–Si System via Mechanochemical Treatment
Authors: Yu Tao , Ye Jiandong , Zhang Shujiang
Published: August 2010

In the present study, the Si‐substituted amorphous calcium phosphate (Si‐ACP) was prepared via a dry‐mechanochemical method, and the hydration behavior of Si‐ACP was investigated by X‐ray diffraction, X‐ray photoelectron spectroscopy, scanning electronic microscopy, and the determination of the setting time and compressive strength. The results showed that the mechanochemical treatment had a great effect on the resolution property of Si‐ACP, which induced the different hydration behavior. With the presence of Si, the hydration product of Si‐ACP showed better results of cell proliferation and metabolic activity, which were characterized by the methyl thiazolyl tetrazolium assay (MTT) with mesenchymal stem cells. This work was expected to have a guiding effect on the study of calcium phosphate cement.
Synthesis of Gallium–Aluminum Dawsonites and their Crystal Structures
Authors: Watanabe Tsunenori , Masuda Takeo , Miki Yoshihisa , Miyahara Yuya , Jeon Hyung‐Joon , Hosokawa Saburo , Kanai Hiroyoshi , Deguchi Hiroshi , Inoue Masashi
Published: August 2010

Solid solutions of dawsonites, ammonium aluminum carbonate hydroxide–ammonium gallium carbonate hydroxide, were obtained by the addition of aqueous solutions of mixtures of aluminum and gallium nitrates to an excess ammonium carbonate solution. The dawsonite solid solutions were calcined at 700°C to give γ‐Ga2O3–Al2O3 solid solutions. The structures of these two types of solid solution were discussed on the basis of their X‐ray diffraction patterns and X‐ray absorption fine structure spectra.
Purpura Fulminans: Report of a case successfully treated with heparin and hydrocortisone Review of 50 cases from the literature
Authors: Hjort Peter F. , Rapaport Samuel I. , Jørgensen Leif
Published: August 2010

Severe purpura fulminans (p. f.) developed in a three year old boy four days after an attack of diarrhea. Streptococci were found in his throat. He went into shock following massive bleeding into the skin. Haemostatic studies revealed moderate thrombocytopenia and profound clotting defects compatible with intravascular coagulation. Skin biopsies disclosed thrombosis of small blood vessels. He improved dramatically after treatment with heparin and hydrocortisone; his clotting factors quickly returned to normal. Following extensive skin grafting, he made a complete recovery.

Fifty selected cases of p. f. have been reviewed. P. f. appears to occur only in children, usually 1–4 weeks after a benign infection, such as scarlatina or varicella. The clinical findings have been described in detail. All patients appear to have one or more episodes of intravascular coagulation resulting in secondary haemostatic defects.

A concept of pathogenesis has been presented in terms of (1) preparation of the skin by mechanism as yet unknown, followed by (2) an episode of acute intravascular coagulation which deposits thrombi in small blood vessels of the prepared skin by mechanisms as yet unknown, followed by (2) an episode of acute intra‐been discussed. Therapy should be based upon heparin to stop intravascular clotting and adrenal steroids to modify possible antigen‐antibody reactions.
The Activity of Lactic Dehydrogenase in Megaloblastic Anaemia
Authors: Anderssen Norman
Published: August 2010

Lactic dehydrogenase activity (LDH) was examined in patients with megaloblastic anaemia and other types of anaemia. Only in untreated megaloblastic anaemia was LDH consistently increased. The increase was not related to the concentration of vitamin B12 and bilirubin in serum. Nor was there any definite relation to the degree of anaemia, but the number of patients examined was too small to permit any final conclusion on this point. The mean LDH value in megaloblastic anaemia was 3,800 units, while the mean value among controls was 257 units. There was a rapid fall in LDH activity during treatment with vitamin B12, corresponding to the increase in reticulocyte counts. In the other types of anaemia studied – acute haemorrhage, chronic haemorrhage and iron deficiency, myelomatosis, aplastic anaemia and anaemia due to renal failure – LDH activity was usually normal or only slightly increased, except in renal failure. In the latter condition the highest LDH value was 830 units, whereas the lowest value in patients with megaloblastic anaemia was 1,510 units.

It is therefore concluded that LDH determinations are of diagnostic aid in differentiating megaloblastic anaemia from other types of anaemia.
Immunochemical Properties of Cold Haemagglutinins
Authors: Harboe Morten , Deverill Johanna
Published: August 2010

In six cases of the cold haemagglutinin syndrome, the isolated cold haemagglutinin was electrophoretically markedly homogeneous when compared with the total γ1‐macroglobulin of the same sera and consisted of group I molecules only. In three of the cases, individually specific antigenic determinants were demonstrated on the isolated cold haemagglutinin. These determinants were unrelated to the antibody specificity. In one serum it could be demonstrated that only cold haemagglutinin molecules contained the individually specific antigenic determinants, and they were present on all molecules with cold haemagglutinin activity. By dissociation of the γ1‐macroglobulin molecules, cold haemagglutinin activity and individually specific antigenic determinants were lost. By removal of the reducing agent, the macroglobulin molecules reassociated with return of both phenomena.
Studies on the Effect of Aspiration Biopsy on the Viability of Aspirated Cells.
Authors: Criborn C. O. , Franzén S. , Unsgaard B. , Zajicek J.
Published: August 2010

A device is described by which pressure differences in the apparatus during aspiration biopsy can be registered. Analyses of pressure were made during aspiration from human bone marrow and human lymph node. The flow of sternal marrow into the syringe was correlated with the pressure difference arising in the system.
Idiopathic Haemosiderosis
Authors: Ploem J. E. , Otten K. , Huizinga J. , Verloop M. C.
Published: August 2010

Two brothers, one with hepatic haemosiderosis and the other with hepatic haemochromatosis, died with clinical symptoms of acute abdominal pain and irreversible shock. In view of these deaths, 35 relatives were examined. The iron metabolism was studied by determination of the amount of stainable iron in the liver tissue, the fasting serum iron concentration, the iron saturation percentage of transferrin and the iron excretion in 24‐hours urine following intramuscular administration of 1000 mg desferrioxamine B.

A defect in iron metabolism was found in three generations. The findings are most readily compatible with the view that a dominant autosomal gene is responsible for the occurrence of the metabolic defect.
Erythropoietin in Serum from Patients with Leucosis Assays in Starved Rats
Authors: Thorling Eivind B.
Published: August 2010

The results are reported of a study on the E.S.F. (erythropoietic‐stimulating‐factor) in serum from 47 patients with leucosis and 11 patients with other haematological disorders, and a survey is given of previous studies of the same nature

The analyses were performed over a period of 2 years

Fe59 incorporation in the erythrocytes in starved rats was used as a criterion of the E.S.F. content in serum

In patients with chronic lymphatic leucosis and acute leucosis, a reciprocal relationship was found between the E.S.F. titre and the haemoglobin percentage, and a similar reciprocal relationship was found between the E.S.F. titre and the bone marrow erythropoiesis. This must be interpreted to mean that there are other factors which determine these patients' defective erythropoiesis

In patients with chronic myeloid leucosis, low values of E.S.F. were found in serum in spite of often reduced haemoglobin levels. Patients with high titres were observed, however, but in these cases the extramedullary erythropoiesis was inhibited, partly because of splenectomy, partly caused by roentgen treatment of the spleen. It seems reasonable to assume that the extramedullary, often ineffective splenic erythropoiesis requires E.S.F., and this might result in the low serum level and perhaps indirectly deprive the bone marrow of its natural stimulation
On the Occurrence of Methylcobalamine in Human Liver
Authors: Ståhlberg Karl‐Gustav
Published: August 2010

In 1961 Toohey & Barker reported findings suggesting that 5,6‐dimethylbenzimidazole‐coenzyme B12 (DMB‐coenzyme B12) may represent the bulk of the B12 content of the human liver. In investigations of the forms of B12 in normal human plasma Lindstrand & Ståhlberg (1963) discovered a predominant, labile form of B12, which they provisionally called the “fourth factor”. The finding was followed up by studies on pig's liver, in which they found a form of B12 showing the same lability and chromatographic properties as the fourth factor (Lindstrand & Ståhlberg 1963). The fourth factor in pig's liver is probably identical with methylcobalamine (Lindstrand 1964), and much suggests that this also holds true for the fourth factor in human plasma (Ståhlberg 1964)

The finding of the fourth factor in human plasma and pig's liver prompted investigation of the types of B12 occurring in the human liver. The chromatographic and bioautographic techniques used revealed the occurrence of B12 forms with the chromatographic properties of methylcobalamine and DMB‐coenzyme B12.
The Biphasic Appearance of Labelled Lymphocytes in the Blood after Single Injections of H3‐Thymidine
Authors: Lundmark Karl Martin , Fichtelius Karl‐Erik
Published: August 2010

In earlier work Fichtelius (1951) demonstrated a biphasic appearance of labelled lymphocytes in the blood after a single injection of P32 as orthophosphate. The second activity increase was at that time explained in three alternative ways: re‐circulation, reutilization or delayed output.

This biphasic appearance of labelled lymphocytes in the blood was confirmed in this new study in rabbits using H3‐thymidine. To‐day all three alternative explanations are still possible and more work is needed for a certain interpretation of the second activity peak observed.
Histochemical Demonstration of Lactate Dehydrogenase in Cells in Blood Films
Authors: Bohn Leif
Published: August 2010

A method for histochemical demonstration of Lactate Dehydrogenase in cells in blood films, employing agar for fixation, is described and the findings with normal cells are presented. The effect of PMS in the substrate is briefly discussed.
An Atypical Circulating Anticoagulant
Authors: DOUGLAS A. S. , CLATANOFF D. V. , MCNICOL G. P. , BAILEY P. A. M.
Published: August 2010

A male, aged 40 years of age, with severe hypertension and biological false positive Wassermann reaction was found incidentally to have a circulating anticoagulant with certain atypical features. The thromboplastin generation test at the standard dilutions was normal with control plasma as substrate, but abnormal when the patient's plasma was used as substrate. There was a prolonged one stage pro‐thrombin time not corrected by normal plasma. Prothrombin was deficient but the patient plasma did not destroy a normal plasma's prothrombin on incubation.
Consumption of Serum Factors and Prothrombin During Intravascular Clotting in Rabbits
Authors: RAPAPORT SAMUEL I. , HJORT PETER F. , PATCH MARY JANE , JEREMIC MICHAEL
Published: August 2010

We have studied the effect of experimental intravascular clotting upon Factors II, VII, IX, and X in rabbits. Animals were given sodium warfarin intravenously to block the synthesis of these factors and, 4 hours later, were infused with either dilute tissue thromboplastin or saline. The tissue thromboplastin induced intravascular clotting extensive enough to halve fibrinogen and platelet levels and to reduce markedly Factor V and Factor VIII levels. These changes resulted from a consumption during clotting of about 10 per cent of the available prothrombin.

Each of the serum factors fell further during the infusion of tissue thromboplastin than during the infusion of saline; apparently, serum factors activated during clotting do not circulate in the rabbit. Net losses due to intravascular clotting equalled about 15 to 30 per cent of the Factors VII, IX, and X initially present. These data suggest that consumption during intravascular clotting may account for the low levels of Factors VII, IX, and X described in patients with diffuse intravascular clotting complicating septicaemia.

The evidence of consumption of Factor IX raises the possibility that tissue thromboplastin may activate intrinsic clotting during hemostasis in vivo.
Liver Iron and Desferrioxamine‐Induced Urinary Iron Excretion
Authors: Hallberg Leif , Hedenberg Lars , Weinfeld Aleksander
Published: August 2010

The desferrioxamine (DF)‐induced urinary iron excretion was measured in subjects in whom surgical biopsy specimens were used to determine liver non‐haemin iron.

A very high correlation was observed between the increase of the urinary iron excretion after administration of DF on the one hand and the concentration of total non‐haemin, ferritin, and haemosiderin iron of the liver on the other.

The studies were made in 10 female and 18 male subjects. Most subjects were considered normal with respect to liver function and iron state. Two male subjects with portal liver cirrhosis fell outside the normal relationship liver iron/urinary iron.

The findings are discussed with special reference to the possible use of DF to quantitate iron stores.
Erythropoietin in Children II. Findings in Hypoxic Polycythaemia
Authors: Okcuoglu Ayhan , Jones Barbara
Published: August 2010

Erythropoietin activity was determined in 18 patients with cyanotic congenital heart disease and 22 cord blood samples from normal fullterm infants. Fifteen of 18 patients with heart disease and all of the cord bloods failed to show increased erythropoietin activity. Two of the cardiac patients had minimal activity and one had an elevated erythropoietin level which was probably a response to acute blood loss. It is suggested that in chronic hypoxic polycythaemia a steady state relative to erythropoiesis exists in which the erythropoietin production essentially equals its utilization.
Morphological Changes in the Hyalomere of Rat Blood Platelets in Experimental Venous Thrombi
Authors: Behnke O.
Published: August 2010

The fine structure of rat blood platelets aggregated in experimentally produced thrombi was examined by light‐ and electron microscopy after glutaraldehyde fixation.

In the ‘body’ regions of the thrombi two kinds of platelet aggregates, arranged in irregular but distinct zones, could be distinguished. In one of the zones platelets were totally degranulated and appeared as nearly empty sacs. In the other zone degranulation was less extensive, and fine, approximately 50 Å thick filaments were a prominent feature of the hyaloplasm.

Microtubules were present in the hyaloplasm of platelets in both zones. The filaments and the microtubules are suggested as possible morphological substrates of the contractile proteins known to be present in platelets.
The Kinetics of Eosinophil Granulocytes in Rats
Authors: Bro‐Rasmussen Frede , Andersen Vagn , Henriksen Ole
Published: August 2010

The kinetics of eosinophil granulocytes have been studied in rats by autoradiography of blood smears made at different times after a single injection of tritiated thymidine.

The main results are 1) The average generation time of eosinophil precursors is about 40 hours – 2) The emergence time for blood eosinophils is 36 hours – 3) The Blood Transit Time of eosinophils has a maximal value of 24 hours.
The Effect of Antigens on DNA‐Synthesis in Cultured Lymphocytes
Authors: Bouveng R. , Gardell S. , Löw B. , Nordén Å.
Published: August 2010

Lymphocytes were isolated from the peripheral blood of healthy blood donors and stimulated in vitro to DNA‐synthesis by the addition of antigens. The addition of two or four antigens to the same culture of lymphocytic cells did not increase the synthesis of DNA above the level induced by a single antigen. Controls with phytohaemagglutinin showed that the in vitro conditions did not represent limiting factors for the synthesis of DNA.

It appears that the response of isolated peripheral blood lymphocytes to one antigen is maximal and that further stimulation with more antigens can not produce the additive effect expected if there were separate clones of lymphocytes for each antigen.
Studies on Hypoxia V. Changes in the Bone Marrow During Hypoxia at 10,000 and 20,000 Feet
Authors: Yoffey J. M. , Smith N. C. W. , Wilson R. S. E.
Published: August 2010

The bone marrow was studied by a quantitative technique in two groups of guinea pigs subjected to hypoxia at a simulated altitude of 10,000 feet and 20,000 feet respectively for periods ranging from 1–5 days. Reticulocytes fall during the first 2 days and then rise, the change being more marked at 20,000 feet than at 10,000 feet. Nucleated erythroid cells rise slightly at 10,000 feet, markedly at 20,000 feet, reaching a peak on the 4th day. Lymphocytes fall very significantly at 20,000 feet, but not at 10,000 feet. Myeloid cells fall in both groups, as do the eosinophils, but again the change is much more striking at 20,000 feet than at 10,000.
Determination of Platelet Factor‐3 by a Modified Prothrombin Consumption Test
Authors: Farská Irena , Pudlák Pavel
Published: August 2010

A method for the determination of platelet factor‐3 by means of a prothrombin consumption test has been developed. The suspension of platelets with a concentration of 50–100,000/μl is washed three times. The results are expressed in percentage of residual prothrombin. The method is also useful in thrombocytopenic states.
Lack of Cytotoxicity by Human Thymocytes in Vitro
Authors: Holm Göran
Published: August 2010

The phytohaemagglutinin (PHA)‐induced cytotoxic action of human blood lymphocytes against homologous cells in tissue culture was compared with the effect of human thymus cells. For quantitation of cell damage, use was made of the release of isotope from Chang cells (human liver) labelled with 51Cr‐chromate. Two young male patients with congenital heart defects served as donors. The Chang target cells were not damaged by thymic lymphoid cells added in high excess. In contrast, a small number of blood lymphocytes from the same donors tested simultaneously damaged the target cells. The thymic cells were poorly stimulated to DNA synthesis and into blastoid transformation by incubation with PHA for 3 days. PPD induced no response in the thymus cells. The blood lymphocytes reacted normally in all tests. Most thymocytes survived 24 hr inkubation while only about 25 per cent were alive after 72 hr. 70 per cent blood lymphocytes survived 72 hr incubation.

It is assumed that a majority of the human thymic lymphocytes are immunologically non‐competent cells in regard to cellular immune reactivity. These cells lack cytotoxicity as well as ability to proliferate in the presence of PHA or antigens.
Mechanisms of Leukocyte Production and Release VIII Eosinophil and Neutrophil Kinetics in Rats
Authors: Cohen Natalie S. , LoBue J. , Gordon A. S.
Published: August 2010

Eosinophil and neutrophil kinetics were compared in normal rats and in rats subjected to repeated leukocyte, particularly eosinophil, removal following a single injection of tritiated thymidine.

Analysis of neutrophil labelling in normal rats provided data on neutrophil production which were in agreement with results of similar studies in dogs and in humans. Some phases of neutrophil life cycles (e.g., maturation time), appeared to be shorter than those of other animals. Labelled mature neutrophils were seen in the bone marrow as early as 16 hours after isotope administration.

In normal rats eosinophil myelocyte turnover and maturation time were estimated as 3 days and 8–12 hours respectively. Labelled eosinophils were seen in the circulation 2 days after isotope injection. The turnover time of mature marrow eosinophils was approximated as 19 hours and that of circulating eosinophils as 4.5 days with a tissue life of 2–4 days.

Rats subjected to leukocytapheresis seemed to exhibit a general acceleration of granulocytopoiesis, as indicated by a shortening of cell generation times and possibly also of maturation times.