bluuebunny/crossref_metadata_2025_split huggingface dataset:
DOES BLUE LIGHT AFFECT THE GROWTH OF CHAETOCEROS PROTUBERANS (BAGILLARIOPHYGEAE)?1
Authors: Gostan Jacques , Lechuga‐Deveze Carlos , Lazzara Luigi 
Published: March 2008

ABSTRACT If one wishes to distinguish chromatic effects from irradiance effects on metabolism. it is technically invalid to expose cells lo irradiances of equal photosynthetically available radiation (PAR) unless PAR is absorbed in totality. Therefore, the effects of blue light on growth and cellular concentrations of carbon, protein and carbohydrate of the diatom Chaetoceros protuberans Lauder, (in semi‐continuous cultures), were studied by exposing the cells to irradiances of equal photosynthetically usable radiation (PUR), of white (PURw) and blue (PURb) light. Three average levels: PURw=PURb=56, 125 and 13 μ m−2.s−1 were used in the stated sequence. With increasing PUR the relative concentration of carbohydrate increased in both types of light. The efficiency of this increase was not modified by blue light. The relative concentration of protein remained constant in white light out the efficiency of net protein production improved at the lowest blue light irradiance. The saturation threshold of this chromatic effect was higher in C. proluberans than in the Chlorophyceae. The chromatic change did not affect the average cell doubling rate, calculated over (5 or 6 days) an observation which does not agree with recently published work.
EFFECT OF CONTROLLED ENVIRONMENTAL CONDITIONS ON STARCH AND AGAR CONTENTS OF GRACILARIA SP. (RHODOPHYCEAE)1
Authors: Rotem Avi , Roth‐Bejerano Nurit , Arad Shoshana (Malis) 
Published: March 2008

ABSTRACTThe red marine alga Gracilaria sp. (collected on Israel's Mediterranean shore) was grown in the laboratory under controlled conditions. The effects of the medium (natural seawater or enriched seawater) and of irradiance on the following parameters were studied: growth rate, dry weight, content of pigments, CO2 fixation rate, starch content, and the quality and quantity of agar. The total agar content was higher in algae grown in natural seawater than in those grown in enriched seawater and decreased only slightly with increasing irradiance. The agar composition was also different in algae grown in the two media. The starch content was higher in algae grown in natural seawater than in algae grown in enriched seawater, and in algae in both media it increased with increasing irradiance. Since the starch content in Gracilaria can reach 21% on a dry weight basis, it is important to correct for in when determining the agar content.
WATER COLUMN PRODUCTIVITY ATTRIBUTABLE TO DISPLACED BENTHIC DIATOMS IN WELL‐MIXED SHALLOW ESTUARIES1
Authors: Shaffer Gary P. , Sullivan Michael J. 
Published: March 2008

ABSTRACTWe attempted to determine the extent to which benthic diatoms contribute to water column primary productivity in shallow‐water estuaries and to elucidate the primary mechanisms responsible for suspending the diatoms. A perliminary study conducted in Mugu Lagoon, California indicated that productivity of ocean water entering the lagoon during flood tides was often several orders of magnitude less than that of the same water mass about 3 h later. Benthic pennate diatoms displaced from the sediments into the water column accounted for the increase. A more detailed study was conducted in Barataria Estuary, Louisiana where, for one month, daily measurements were made of benthic and water column productivity and several other environmental variables. During the month, the relationship between water column and benthic primary productivity varied from strongly negative to weakly negative to positive. K‐systems analysis indicated that factors comprised of wave height, meteorological tides, astronomical tides, and benthic productivity and standing crop accounted for the full range of variation in water column productivity. Benthic pennate diatoms, represented an average of 74% of the diatom taxa in water column samples. We conclude that the primary productivity of well‐mixed shallow estuarine waters is often greatly aumented by displaced benthic algae.
PHOTOSYNTHETIC PIGMENTS IN FIFTY‐ONE SPECIES OF MARINE DIATOMS1
Authors: Stauber Jennifer L. , Jeffrey S. W. 
Published: March 2008

ABSTRACTThe photosynthetic pigments of 51 species (71 isolates) of tropical and sub‐tropical diatoms from 13 out of 22 families were examined. These were the Thalassiosiraceae, Melosiraceae, Coscinodiscaceae, Rhizosoleniaceae, Biddulphiaceae, Chaetoceraceae, Lithodesmiaceae, Eupodiscaceae, Cymatosiraceae, Diatomaceae, Naviculaceae, Nitzschiaceae and Phaeodactylinaceae. Pigments were analyzed by cellulose and polyethylene thin‐layer chromatography (TLC) and reverse‐phase high‐performance thin‐layer chromatography (HPTLC). All species contained chlorophylls a and c2and the carotenoids carotene, fucoxanthin, diatoxanthin and diadinoxanthin. In addition, 14 species (20 isolates) contained one or more of four minor carotenoids, which were not identified further. One species,Thalassiothrix heteromorpha, contained small amounts of a 19′‐butanoyloxyfucoxanthin‐like pigment, in addition to fucoxanthin.Chlorophyll c2was present in all the diatoms tested and occurred together with chlorophyll c1in 88% of them. The presence of both chlorophylls c1and c2therefore can no longer be considered a universal characteristic of the diatom class. Where chlorophyll c1was absent or occurred in trace amounts only (8 species, 11 isolates), it was usually replaced by a new chlorophyll c pigment designated chlorophyll c3, recently characterized from several prymnesiophytes and one chrysophyte. Exceptions wereNitzschia closterium(CS‐114), which contained only chlorophyll c2, andNitzschia bilobata(CS‐47), which contained all three chlorophylls (c1, c2and c3) in approximately equal amounts. Five species that contained chlorophylls c1and c2also contained chlorophyll c3in trace quantitiesQuantitative pigment analyses of the 71 isolates showed that chlorophyll concentrations ranged from 0.02 μg. 106cells−1in the smallest diatom,Extubocellulus spinifer, to 174.4 μg. 106cells−1in one of the largest diatoms,Coscinodiscussp. under the standard growth conditions used. The mean molar ratio of chlorophylla:cin the 72 isolates was 3.33, with a range of 1.65–7.25.The close similarity between diatom and prymnesiophyte pigmentation was confirmed. Each class has three patterns of pigmentation: viz species with chlorophylls c1and c2and‘true’fucoxanthin, species with chlorophylls c3and c2and‘true’fucoxanthin, and species with chlorophylls c3and c2and fucoxanthin derivatives.
THE ULTRASTRUCTURE OF MITOSIS AND CYTOKINESIS IN THE SARCINOIDCHLOROKYBUS ATMOPHYTICUS(CHLOROPHYTA, CHAROPHYCEAE) REVEALED BY RAPID FREEZE FIXATION AND FREEZE SUBSTITUTION1
Authors: Lokhorst Gijsbert M. , Sluiman Hans J. , Star Wim 
Published: March 2008

ABSTRACTMitosis and cytokinesis in vegetative cells of the sarcinoid green alga Chlorokybus atmophyticus Geitler were examined with rapid freeze fixation, freeze substitution, and transmission electron microscopy. The taxonomic placement of C. atmophyticus in the class Charophyceae sensu Stewart and Mattox is corroborated by some mitotic and cytokinetic features including development of a microtubular sheath around the prophase nucleus, the almost constant chromosome to pole distance during anaphase, telophase nuclei widely separated by a persistent interzonal spindle, and centripetal plasma membrane invagination. Features, previously unknown in the Charophyceae, include the specific position of the peroxisome lying between the nucleus and adjacent cell wall during interphase and mitosis, the extensive array of microtubules radiating from the centrioles located at the presumptive poles at prophase, involvement of coated vesicles in the furrowing process, and occurrence of transversely aligned cleavage microtubules. Placement of Chlorokybus in the order Klebsormidiales is proposed.
THE OCCURRENCE OF FLAGELLATED EGGS IN LAMINARIA ANGUSTATA (PHAEOPHYTA, LAMINARIALES)1
Authors: Motomura Taizo , Sakai Yoshio 
Published: March 2008

ABSTRACTEggs of laminaria angustata Kjellman were shown to have two flagella. Compared with flagella of other phaeophycean swarmers, those of Laminaria eggs have several unique characters such as lack of mastigonemes, widely spaced basal bodies and no flagellar rootlets. The flagella abscise during egg liberation.
QUANTITATIVE AND QUALITATIVE ANALYSES OF PROTEIN SYNTHESIS DURING HEAT SHOCK IN THE MARINE DIATOM NITZSCHIA ALBA (BACILLARIOPHYCEAE)1
Authors: Lai Yiu‐Kay , Li Chia‐Wei , Hu Ching‐Hwa , Lee Man‐Ling 
Published: March 2008

ABSTRACTProtein synthesis in the diatom Nitzschia alba Lewin and Lewin was drastically altered when the cells were incubated at a supraoptimal temperaeture. Quantitatively, the overall protein synthesis was greatly suppressed as indicated by teh rate of [35S] methionine incorporation. The extent of suppression of protein synthesis was proportional to the severity of the heat‐shock treatment which was a combination of elevated temperature and treatment duration.The in viro synthesized proteins were also qualitativelty anlayzed by two‐dimensional gel electrophoresis. Dependeing on the treatment condition, a set of heat‐shock proteins (HSPs) were induced. They were best detected when the cells were subjected to shocks of 35°C for 60 min or 40°C for 10 min followed by a 60 min labelling at 30°C. The results revealed 16 HSps which had moluecular weights ranging from 24–94 kD and isoelectric points ranging from 5.50–7.10. Some of the HSps were identical in molelcular weights but with differeentr isoelectric points.The induction and accumulation of HSPs in Nitzschia alba were transitory. Prologned heat‐shock treatments resulted in a complete cessation of protein syntehsis and no further induction of HSPs. In all aspects, the heat shock response of diatoms was similar to that in higher plants such as soybean, maize and tobacco but differenet from most animal systems.
TEMPERATURE TOLERANCE OF NORTHEAST PACIFIC MARINE ALGAE1
Authors: Lüning Klaus , Freshwater Wilson 
Published: March 2008

ABSTRACTTemperature tolerance (1 week exposure time) was investigated in 49 species of benthic marine macroalgae and two seagrass species from San Juan Island (Washington) or Vancouver Island, British Columbia. Positive net photosynthesis was the parameter used to detect survival. Most algal species survived ‐1.5° C (the lowest applied temperature), and none 30° C. The most heat‐tolerant, eurythermal algal species survived 28° C: these were Ahnfeltia plicata, Mastocarpus papillatus (as crustose tetrasporophyte), Endocladia muricata, and Sargassum muticum. In contrast, most representatives of the Laminariales exhibited a cold‐stenothermic character: Cymathere triplicata, Pleurophycus gardneri, Hedophyllum sessile, Postelsia palmaeformis survived up to only 15° C, and Laminaria saccharina, L. groenlandica, L. setchellii to 18° C. As to the seagrass species, Zostera marina survived a temperature range of ‐ 1.5 to 30° C and Phyllospadix scouleri a range of ‐ 1.5 to 25° C. For many of the sublittoral species there was agreement between maximum survived temperatures in our experiments and average maxima of summer temperatures at the southern geographical limits of the species. Specimens of four species exhibited upper survival limits similar to those of conspecifics in the North Atlantic; namely, Desmarestia ‘aculeata, D. viridis, Plocamium cartilagineum, and Ahnfeltia plicata. These results favor the interpretation of upper temperature survival limits as conservative taxonomic traits.
EFFECT OF ENVIRONMENTAL CONDITIONS ON FATTY ACID COMPOSITION OF THE RED ALGA PORPHYRIDIUM CRUENTUM: CORRELATION TO GROWTH RATE1
Authors: Cohen Zvi , Vonshak Avigad , Richmond Amos 
Published: March 2008

ABSTRACT The lipid and fatty acid composition of Porphyridium cruentum was determined as a function of light intensity, temperature, pH, and salinity. In cultures cultivated at the optimal temperature under non‐limiting light conditions, eicosapentaenoic acid was the main polyunsaturated fatty acid. When growth rate was reduced by decreased light intensity, increased cell concentration, suboptimal temperature, suboptimal pH, or increased salinity, the content of eicosapentaenoic acid decreased and that of arachidonic acid increased, the latter becoming the major polyunsaturated fatty acid.
ZONATION OF DEEP WATER BENTHIC ALGAE IN THE GULF OF MAINE1
Authors: Vadas Robert L. , Steneck Robert S. 
Published: March 2008

ABSTRACT Algal community structure is described for a deep‐water rock pinnacle in the Gulf of Maine. Three depth zones of algal dominance were apparent consisting of 1) leathery macrophytes (to 40 m), 2) foliose red algae (to 50 m) and 3) crustose algae (fleshy crusts to 55 m and coralline crusts to 63 m). Microscopic filamentous and erect calcareous algae were also present but inconspicuous. Upright macroscopic filamentous and thin sheet‐like forms were not observed on the pinnacle. Sea anemones (Metridium senile) dominated some vertical faces and abrupt prominences in the shallowest regions of the pinnacle (to 24 m) and locally appeared to set the upper vertical limits of kelp and possibly foliose reds. Laminaria sp. formed an open park‐like canopy from 24 to 30 m whereas Agarum cribrosum, the deepest kelp, grew as isolated individuals to 40 m. Peyssonnelia sp. and Leptophytum laeve were the deepest occurring fleshy (to 55 m) and calcareous crusts (to 63 m), respectively. The occurrence of these algae at record depths for the Gulf of Maine and for cold water marine environments may be the result of an absence of large herbivores and the high productivity potential of the benthos in these relatively clear waters. By compiling data on depth distribution patterns world‐wide, it is evident that the three zone structure of algal morphologies observed in the Gulf of Maine is a global phenomenon.
ULTRASTRUCTURE OF FERTILIZATION IN A CRYPTOMONAD1
Authors: Kugrens Paul , Lee Robert E. 
Published: March 2008

ABSTRACTBy means of various electron microscopic techniques, the ultrastructure of fusing gametes in a cryptomonad is described for the first time. The isolate used in this study is bisexual, and vegetative cells may act as isogametes. Plasmogamy usually is initiated at the posterior end of one gamete and the mild‐ventral region of the other gamete. A posterior, pointed protuberance may be a specialized mating structure which initiates the fusion process. Fusion proceeds toward the anterior end, forming a quadriflagellate cell which becomes spherical and settles to the bottom of the culture flask. The quadriflagellate, spherical cell contains two nuclear‐nucleomorph‐chloroplast complexes which remain intact throughout karyogamy. During karyogamy the nuclei are positioned close to each other and become lobed on the sides where fusion takes place. At the points where the lobes touch, the nuclear membranes break down and direct karyogamy is initiated. Nuclear fusion continues and eventually a single zygotic nucleus is formed. The zygote nucleus and the two nucleomorphs and chloroplasts become enclosed in a common periplastidial compartment. The nucleomorphs, however, remain apart and do not fuse. Meiosis presumably is zygotic, but the stages of post‐karyogamy remain to be elucidated.
ULTRASTRUCTURE OF A NEW SAND‐DWELLING DINOFLAGELLATE, SCRIPPSIELLA ARENICOLA SP. NOV1
Authors: Horiguchi Takeo , Pienaar Richard N. 
Published: March 2008

ABSTRACTA new dinoflagellate, Scrippsiella arenicola Horiguchi et Pienaar sp. nov., is described from tidal pools with sandy substrates along the east coast of South Africa. S. arenicola exhibits a vertical migratory rhythm which is in synchrony with the tidal cycle. It is a medium‐sized armoured dinoflagellate with many rod‐shaped chloroplasts. Thecal plate arrangement is pp, x, 4′, 3a, 7′, 6c, 5′, 2″ and 4s. The 2a and 3a plates are separated from each other. S. arenicola has several unique ultrastructural features. Electron‐dense fibres are found on the protruded part of the thecal plates, such as on the ornamental projections or extremities of the lists. In addition to the 9 + 2 axoneme, additional fibres are found in the free moving part of the longitudinal flagellum. The portion of the transverse flagellum covered by the left sulcal list possesses a dense array of mastigonemes which connect the flagellum and the cell. The flagellar pore platelets differ from ordinary thecal plates in their thickness and fibrous nature. The ultrastructure of the apical stalk and its associated structures is described. The vertical migration and mode of cell division is also described.
Do Palliative Consultations Improve Patient Outcomes?
Authors: Casarett David , Pickard Amy , Bailey F. Amos , Ritchie Christine , Furman Christian , Rosenfeld Ken , Shreve Scott , Chen Zhen , Shea Judy A. 
Published: March 2008

OBJECTIVES: To determine whether inpatient palliative consultation services improve outcomes of care.DESIGN: Retrospective telephone surveys conducted with family members of veterans who received inpatient or outpatient care from a Department of Veterans Affairs (VA) medical facility in the last month of life.SETTING: Five VA Medical Centers or their affiliated nursing homes and outpatient clinics.PARTICIPANTS: Veterans had received inpatient or outpatient care from a participating VA in the last month of life. One family member completed each survey.MEASUREMENTS: The telephone survey assessed nine aspects of the care the patient received in his or her last month of life: the patient's well‐being and dignity (4 items), adequacy of communication (5 items), respect for treatment preferences (2 items), emotional and spiritual support (3 items), management of symptoms (4 items), access to the inpatient facility of choice (1 item), care around the time of death (6 items), access to home care services (4 items), and access to benefits and services after the patient's death (3 items).RESULTS: Interviews were completed with 524 respondents. In a multivariable linear regression model, after adjusting for the likelihood of receiving a palliative consultation (propensity score), palliative care patients had higher overall scores: 65 (95% confidence interval (CI)=62–66) versus 54 (95% CI=51–56; P<.001) and higher scores for almost all domains. Earlier consultations were independently associated with better overall scores (β=0.003; P=.006), a difference that was attributable primarily to improvements in communication and emotional support.CONCLUSION: Palliative consultations improve outcomes of care, and earlier consultations may confer additional benefit.
Isolating the Information Content of Equity Analysts' Recommendation Changes, Post Reg FD
Authors: Goff Delbert , Hulburt Heather , Keasler Terrill , Walsh Joe 
Published: March 2008

AbstractWe investigate the information content of equity analysts' recommendation changes subsequent to the passage of Regulation Fair Disclosure. We find that analyst upgrades (downgrades) are associated with positive (negative) abnormal returns. Overall, stock prices tend to react significantly more strongly to recommendation changes accompanied by news events than to those that are not. Even so, returns around recommendation changes not accompanied by news are significantly different from zero. This result holds after controlling for firm‐specific variables and the incidence of multiple simultaneous recommendation changes. We conclude that analyst recommendation changes, in and of themselves, are informative.
The irritant potential of n‐propanol (nonanoic acid vehicle) in cumulative skin irritation: a validation study of two different human in vivo test models
Authors: Clemmensen A. , Andersen F. , Petersen T. K. , Kalden H. , Melgaard A. , Andersen K. E. 
Published: March 2008

Background/purpose: Human in vivo cumulative irritation tests with low‐grade irritants simulate real‐life exposure to skin irritants. The test outcome depends not only on the substance tested but also on the design of the assay. More than one experimental irritant is usually used because chemicals have diverse mechanisms of action on the skin. We used sodium lauryl sulfate (SLS) and nonanoic acid (NON) in three different concentrations plus their vehicles, water and n‐propanol, respectively, to validate our test models and to optimize test concentrations.Methods: Healthy volunteer forearm skin was exposed in two different cumulative test models: a repeated open model (ROAT) and an exaggerated wash test model. ROAT: 10‐min daily exposures for 5+4 days (no irritation on weekend) to SLS 0% (water), 0.5%, 1.0% and 2.0% on the right arm and NON 0% (n‐propanol neat), 10%, 20% and 30% on the left arm. Wash test: induction of irritation by three daily washings for 6 days and maintenance of the dermatitis by two daily washings for 12 days with SLS 0%, 5%, 10% and 15% or NON 0%, 30%, 40% and 50%. Reactions were evaluated clinically and instrumentally (transepidermal water loss, colorimetry and hydration) at sequential time points. Additionally, for the wash test, subjective pain scores were obtained from the volunteers.Results: In the ROAT, n‐propanol exhibited irritation potential at the level of SLS 1.0% and, by visual scoring, was only found to be significantly different from the two highest concentrations of NON (20% and 30%). In the wash test, n‐propanol was much less irritating than SLS, and it could only be distinguished statistically from NON (any concentration) by visual reading. For both test models, n‐propanol, by instrumental measurements, was not significantly different from any NON concentration.Conclusion: In cumulative irritation test assays, n‐propanol appears to be quite irritant itself and may thus be a significant contributor to NON irritation. Moreover, n‐propanol was more irritant in the ROAT compared with the wash test.
Utilisation of dental services in a university hospital palliative and long‐term care unit in Geneva
Authors: Schimmel Martin , Schoeni Patricia , Zulian Gilbert B. , Müller Frauke 
Published: March 2008

Objectives:  Dental care plays an important role in the multidisciplinary approach, which is used in palliative and long‐term care to address the complex needs of terminally ill patients. The aim of this study was to assess the utilisation of dental services in a University Hospital Palliative and Long‐term Care Unit.Material and method:  Over an observation period of 13 months, structured questionnaires were filled in after each dental appointment. The survey covered three main topics: the initiation and incentive from the dental consultation, particular difficulties because of the patient’s health or the hospital’s organisation as well as the accomplished treatment.Results:  Two hundred and seventy‐five questionnaires from a total of 102 patients were available for analysis. The patients’ median age was 83 years (SD 10.3, range 49–101 years), 63 were female, 39 male. A majority of first appointments were initiated by a physician (n = 49 of 102), mainly because of pain (n = 62 of 275). 10.5% of the appointments were cancelled on the same day. Only one‐fifth of the patients were able to reach the practice on foot. Six used a walking stick and 54 relied on a wheelchair. Eighteen patients needed to be seen in their bed. The most frequently performed procedures were extractions and removal of denture sore spots (n = 67 of 275) followed by the manufacturing of new dentures (n = 38 of 275). In more than 17% of the appointments, no particular treatment was performed.Conclusion:  The utilisation of dental services in terminally ill and severely compromised elderly patients shown justifies a dental service in a palliative care or geriatric hospital setting. The particular dental work profile requires a practitioner with empathy and professional experience.