bluuebunny/crossref_metadata_2025_split huggingface dataset:
LOSS OF HYBRID LETHALITY DURING BACKCROSS PROGRAMS INVOLVING CHLAMYDOMONAS EUGAMETOS AND CHLAMYDOMONAS MOEWUSII (CHLOROPHYCEAE)1
Authors: Lee Robert W. , Lemieux Claude 
Published: October 2004

ABSTRACTWild‐type strains of the interfertile species Chlamydomonas eugametos (UTEX 9 and 10) and Chlamydomonas moewusii (UTEX 96 and 97) male readily and reciprocally; however, considerable lethality occurs among F1 hybrid meiotic products. We prepared two hybrid backcross lineages using C. eugametos and C. moewusii. One lineage began with the cross C. eugametos mating‐type‐plus (mt+) × C. moewusii mating‐type‐minus (mt−). An F1 mt+ hybrid from this cross was back‐crossed to C. moewusii mt−, and a B1 mt+ hybrid was recovered. The B1 hybrid was again backcrossed to C. moewusii mt−, and this process was repeated through the fifth backcross. The other backcross lineage began with the reciprocal cross C. moewusii mt+× C. eugametos mt− and employed C. eugametos as the recurring mt− parent. This lineage also was continued through the fifth backcross. Meiotic product survival in the reciprocal interspecific crosses was less than 10%. In successive back‐cross generations associated with both lineages, this value increased progressively to a maximum of 85–90%, the level observed for the intraspecific crosses. These results are consistent with the hypothesis that multiple genetic differences exist between C. eugametos and C. moewusii and that these are the major source of meiotic product lethality associated with the interspecific crosses. The inheritance of chloroplast genetic markers for resistance to streptomycin (sr‐2) and for resistance to erythromycin (er‐nM1) was also scored w the interspecific crosses and in the backcrosses. Most hybrid zygospores transmitted the resistance markers of the mt+ parent only, or of both parents, with the former zygospore type being more common. Although the intraspecific C. eugametos and C. moewusii crosses differ conspicuously with respect to the fraction of zygospores which transmit chloroplast genetic markers of both parents, the inheritance of chloroplast genetic markers in the interspecific crosses and backcrosses at' scribed here failed to clarify the genetic basis for this difference.
PHOTOSYNTHESIS IN PROTOPLASTS OF MACROCYSTIS PYRIFERA (PHAEOPHYTA)1
Authors: Davison Ian R. , Polne‐Fuller Miriam 
Published: October 2004

ABSTRACTPhotosynthetic rates measured in protoplasts isolated from the broivn alga Macrocystis pyrifera (L.) Ag. were compared to those for intact tissue. Both 14C incorporation and O2 evolution gave similar rates of light‐saturated protoplast photosynthesis (approximately 0.4 mmol‐g chl a−1· min−1). Light saturated photosynthetic rates (Pmax) and light harvesting efficiencies (α) of protoplasts were approximately 40% those of intact tissue. In contrast, protoplasts had a greater substrate affinity for photosynthetic HCO3 uptake (lower K0.5) than intact tissue (0.87 and 4.1 mMolar, respectively), presumably because of a reduction in the thickness of the unstirred boundary layer in the absence of the cell wall. Overall, the data suggest that protoplasts isolated from Macrocystis pyrifera are of valur in the study of photosynthesis. However, experiments with intact tissue are necessary as controls to aid interpretation of protoplast data.
LIFE HISTORY AND GROWTH OF LAURENCIA BRACHYCLADOS (RHODOPHYTA, CERAMIALES)1
Authors: McDermid Karla J. 
Published: October 2004

ABSTRACT Laurencia brachyclados Pilger from Hawai'i completed a “Polysiphonia‐type” tri‐phasic life history in 21 weeks in laboratory culture. Tetraspores developed into gametophytes in a nearly 1:1:1 ratio of females: males: non‐reproductive. Carpospores were released as early as 21 days after mixing virgin female and male gametophytes. Cultured thalli showed a “guerilla type” growth form. Other Hawaiian Laurencia species in culture had longer maturation times or remained non‐reproductive. Variation in life history schedules may influence Laurencia species coexistence and algal community structure.
ELECTRON MICROSCOPY OF NANOPLANKTON FROM THE NORTH PACIFIC CENTRAL GYRE1
Authors: Hoepffner Nicolas , Haas Leonard W. 
Published: October 2004

ABSTRACTNanoplankton was collected from the North Pacific Central Gyre during a cruise of R/V “Melville” in August 1985. Water samples from the surface and the deep chlorophyll maximum layer were fixed with glutaraldehyde and prepared for electron microscopy observation using formvar coated grids. The grids were examined first by epifluoresence microscopy under blue light to differentiate chloroplast and non‐chloroplast containing cells. The surface and deep samples were dominated strongly by members of the Prymnesiophyceae, accounting for 55% of the total number of organisms identified. Prymnesiales and Coccosphaerales were equally abundant although coccoliths‐bearing cells tended to dominate in the deep chlorophyll maximum layer. Heterotrophic choanoflagellates were also abundant at depth and were characterized by a high species diversity. Micromonas pusilla (Butcher) Manton & Parke was the major representative of the Prasinophyceae and was observed commonly within the deep chlorophyll maximum. Our observations reveal several new species, including autotrophic and heterotrophic specimens, and demonstrate the importance of knowing the structure of the planktonic community for ecological purposes. Indeed, the presence of a large number of heterotrophic organisms in the deep water suggests an active microbial food chain which may play an important role in regulating plankton processes in oligotrophic waters.
A NOVEL ASSOCIATION BETWEEN AN ENDEMIC STICKLEBACK AND A PARASITIC DINOFLAGELLATE. 2. MORPHOLOGY AND LIFE CYCLE1
Authors: Buckland‐Nicks John A. , Reimchen Tom E. , Taylor Max F. J. R. 
Published: October 2004

ABSTRACTAn unusual dinoflagellate has been discovered in association with an endemic population of stickleback,Gasterosteus(L.), from the Queen Charlotte Islands, Canada. The dinoflagellate spends most of its life cycle as a coccoid vegetative cyst, not as a parasitic trophont. The vegetative cyst is unique in containing a rigid fenestrated matrix, which is penetrated by cytoplasmic process that emanate from a central area containing the dinokaryotic nucleus and associated chloroplasts. Some pores in the matrix are filled by oil droplets or starch granules. Intracellular bacteria are found throughout the cyst, sometimes in association with the nucleus. The cytoplasm contains accumulation bodes, microbodies, polyhedral crystals, chloroplasts and polyvesicular bodes. The encysted dinoflagellate has several potential strategies. It can 1) shed its wall and become amoeboid; 2) undergo sporogenesis and give rise to both regular and resistant spores; 3) divide mitotically, with a gradual reduction in the size of daughter cells down to 20 μm; and 4) apparently form a resting cyst, during which it secretes a thick outer wall composed of five layers. Taxonomically, this unusual dinoflagellate appears to be a new member of the Blastodiniales, although its position will become clearer when details of the motile stage are known.
STUDIES OF VANDADIUM‐BROMOPEROXIDASE USING SURFACE AND CORTICAL PROTOPLASTS OF MACROCYSTIS PYRIEFERA (PHAEOPHYTA)1
Authors: Butler Alison , Soedjak Helena S. , Polne‐Fuller Meiram , Gibor Aharon , Boyen Catherine , Kloareg Bernard 
Published: October 2004

ABSTRACTAqueous Tri‐SO4 buffer (pH 8.3) extracts of cortical and surface protoplasts of Macrocystis pyrifera (L.) C. Ag. Catalyzed the bromination of monochlorodimedone (2‐chloro‐5, 5‐dimethyl‐1, 3‐dimedone, MCD) in the presence of hydrogen peroxide and bromide. The apparent bromo‐peroxidase activity as measured by the bromination of MCD was inhibited by the presence of endogenous compounds which are probably polyphenolics compounds (i.e. polymers of phloroglucinol) or other inhibitors. The bromoperoxidase activity of the protoplast extracts increased substantially when the extracts were washed extensively with Tris‐SO4 buffer (pH 8.3) by ultrafiltration. The bromoperoxidase activity of both surface and cortical protoplast extracts was dependent on the presence of vanadium, indicating that the bromoperoxidase present in cortical and surface cells of M. pyrifera is vanadium‐bromoperoxidase. Halogenated compounds constitute one of the most significant classes of marine natural products. Since bromoperoxidases are assumed to be involved in the biosynthesis of these compounds, elucidation of the location of BrPO with in the algal tissue is important.
COPPER TOLERANCE OF CHLAMYDOMONAS ACIDOPHILA (CHLOROPHYCEAE) ISOLATED FROM ACIDIC, COPPER‐CONTAMINATED SOILS1
Authors: Twiss Michael R. 
Published: October 2004

ABSTRACTCells of Chlamydomonas acidophila Negoro, isolated from three soils with different available copper contents (74, 80, and 87 μg·g−1), were assayed for their responses to copper. Soil pH ranged from 3.3–3.9. Responses were evaluated using algistatic assays involving five day exposure to copper concentrations from 0.1–100 mg·L−1 at pH 3.8 and 6.6 in defined liquid media. Interspecies and intraspecies comparisons were made between the soil isolates and laboratory strains of C. reinhardtii and C. acidophila, respectively. Algistatic copper concentrations of soil isolates were 20–125 times greater than those of the laboratory strain of C. reinhardtii. Concentrations of 0.1 mg Cu·L−1, or greater, killed the laboratory strain of C. acidophila. Soil isolates of C. acidophila appeared to be copper tolerant; however, there was no conclusive evidence to indicate that the level of copper tolerance in the soil isolates was positively correlated with the level of available copper in the soil.
PIGMENT AND PHOTOSYNTHETIC RESPONSES OF OSCILLATORIA AGARDHII (CYANOPHYTA) TO PHOTON FLUX DENSITY AND SPECTRAL QUALITY1
Authors: Millie David F. , Ingram Daphne A. , Dionigi Christopher P. 
Published: October 2004

ABSTRACTThe effects of photon flux density (PFD) and spectral quality on biomass, pigment content and composition, and the photosynthetic activity of Oscillatoria agardhii Gomont were investigated in steady‐state populations. For alterations of PFD, chemostat populations were exposed to 50, 130 and 230 μmol photons·m−2·s−1 of photosynthetic active radiation (PAR). Decreases in biomass, chlorophyll a (Chl a) and c‐phycocyanin (CPC) contents, and CPC: Chl a and CPC: carotenoid content was not altered. Increases in the relative abundances of myxoxanthophyll and zeaxanthin and deceases in the relative abundances of echinenone and β‐carotene within the carotenoid pigments coincided with increasing PFD. Increases in Chl a‐specific photosynthetic rates and maxima and decreases in biomass‐specific photosynthetic rates and maxima with increasing PFD were attributed to increased light harvesting by carotenoids per unit Chl a and reduction in total pigment content, respectively.Responses to spectral quality were tested by exposing chemostat populations to a gradient of spectral transmissions at 50 μmol photons·m−2·s−1 PAR. Biomass differences among populations were likely attributable to the distinct absorption of the PAR spectrum by Chl a, CPC, and carotenoids. Although pigment contents were not altered by spectral quality, relative abundances of zeaxanthin and echinenone in the carotenoid pigments increased in populations exposed to high‐wavelength PAR. The population adapted to green light possessed a greater photosynthetic maximum than populations adapted to other spectral qualities.
PHYLOGENY OF THE ULVOPHYCEAE (CHLOROPHYTA): CLADISTIC ANALYSIS OF NUCLEAR‐ENCODED rRNA SEQUENCE DATA1
Authors: Zechman Frederick W. , Theriot Edward C. , Zimmer Elizabeth A. , Chapman Russell L. 
Published: October 2004

ABSTRACTCladistic analysis of nuclear‐encoded rRNA sequence data provided us with the basis for some new hypotheses of relationships within the green algal class Ulvophyceae. The orders Ulotrichales and Ulvales are separated from the clade formed by the remaining orders of siphonous and siphonocladous Ulvophyceae (Caulerpales, Siphonocladales /Cladophorales [S/C] complex, and the Dasycladales), by the Chlorophyceae and Pleurastrophyceae. Our results suggest that the Ulvophyceae is not a monophyletic group. Examination of inter‐ and intra‐ordinal relationships within the siphonous and siphonocladous ulvophycean algae revealed that Cladophora, Chaetomorpha, Anadyomene, Microdictyon, Cladophoropsis and Dictyosphaeria form a clade. Thus the hypothesis, based on ultrastructural features, that the Siphonocladales and Cladophorales are closely related is supported. Also, the Caulerpales is a monophyletic group with two lineages; Caulerpa, Halimeda, and Udotea comprise one, and Bryopsis and Codium comprise the other. The Dasycladales (Cymopolia and Batophora) also forms a clade, but this clade is not inferred to be the sister group to the S/C complex as has been proposed. Instead, it is either the sister taxon to the Caulerpales or basal to the Caulerpales and S/C clade The Trentepohliales is also included at the base of the siphonous and siphonocladous ulvophycean clade. The Pleurastrophyceae, which, like the Ulvophyceae, posses a counter‐clockwise arrangement of flagellar basal bodies, are more closely related to the Chlorophyceae than to the Ulvophyceae based on rRNA sequences. Thus, the arrangement of basal bodies does not diagnose a monophyletic group. Previously reported hypotheses of phylogenetic relationships of ulvophycean algae were tested. In each case, additional evolutionary steps were required to obtain the proposed relationships. Relationships of ulvophycean algae to other classes of green algae are discussed.
LIFE HISTORY AND SYSTEMATIC POSITION OF PSEUDOCHORDA GRACILIS SP. NOV. (LAMINARIALES, PHAEOPHYCEAE)1
Authors: Kawai Hiroshi , Nabata Shin‐ichi 
Published: October 2004

ABSTRACT Pseudochorda gracilis sp. Nov. (Pseudochordacease, Laminariales) is described from the Japan Sea coast of Hokkaido/ the species is subtidal, epilithic and annual, appearing in spring and maturing in winter. Erect thalli grow solitary or in tufts on a small discoid holdfast. They are simple, cord‐shaped and hollow, with inner hyphal filaments, cylindrical medullary cells and paraphyses consisting of 3–6 cells. Hair tufts are observed only in young thalli. Unilocular sporangia are sessile and narrowly ovate. In culture, P. gracilis shows a heteromorphic life history with oogamy, characteristic of the order Laminariales. Gametophytes are dioecious and dimorphic. Gametophytes mature under lower temperature conditions (usually below 10°C), and sporophytes mature under low temperature and short‐day conditions (5°C, SD). The seasonal growth pattern of the species results from the photoperiod‐temperature conditions controlling saprophyte maturation.
The Incidence and Intensity of Employer Funded Training: Australian Evidence on the Impact of Flexible Work
Authors: Draca Mirko , Green Colin 
Published: October 2004

AbstractThe interaction between the growth of flexible forms of employment and employer funded training is important for understanding labour market performance. In particular, the idea of a trade‐off has been advanced to describe potential market failures in the employment of flexible workers. This study finds that evidence of a trade‐off is apparent in both the incidence and intensity of employer funded training. Flexible workers receive training that is 50–80% less intense than the workforce average. Casual workers – especially males – suffer more acutely from the trade‐off. This suggests that flexible production externalities may seriously reduce human capital formation in the workforce.
Hybrid Inflation‐Price‐Level Targeting in an Economy With Output Persistence
Authors: Kobayashi Teruyoshi 
Published: October 2004

AbstractThis paper investigates hybrid inflation‐price‐level targeting (HT), employing a Phillips curve with output persistence. By HT we mean that a central bank targets a weighted average of the optimal inflation rate and its corresponding price level. The analysis shows that if output is persistent to some extent, it is desirable to adopt HT because, relative to the case of alternative regimes such as inflation targeting (IT) and price‐level targeting (PT), it will reduce the variability of inflation and thereby social loss. In addition, it is shown that the optimal hybrid‐type target is uniquely determined according to the degree of persistence in output.
Is There a Trade‐Off Between Inflation Variability and Output‐Gap Variability in the EMU Countries?
Authors: Arestis Philip , Mouratidis Kostas 
Published: October 2004

AbstractThis paper examines the performance of monetary policy in eleven EMU countries for the whole period of the EMS. This is based on the trade‐off between inflation variability and output‐gap variability. To this end, we examine whether the introduction of an implicit inflation targeting by the EMU member countries after the Maastricht Treaty, changed the trade‐off between inflation variability and output‐gap variability. We employ a stochastic volatility model for two sub‐periods of the EMS (i.e. before and after the Maastricht Treaty). We find that the trade‐off varies amongst EMU countries. The implication of these findings is that there are asymmetries in the euro area, due to different economic structures among the member countries of the EMU.
Welfare, Growth and Environment: A Sceptical Review of the Skeptical Environmentalist by B. Lomborg
Authors: FitzRoy Felix , Smith Ian 
Published: October 2004

AbstractLomborg's best‐selling attempt to demolish environmental concerns has been praised by the Economist and the Financial Times, in stark contrast to the reactions of environmental scientists. We show in detail here how Lomborg selects statistics to support his optimistic views, and systematically neglects relevant but unfavourable evidence. He also ignores much of modern environmental economics, such as the use of genuine investment that captures environmental degradation, ‘double dividends’ from green taxation in the presence of unemployment, and local health benefits from abatement of emissions.
Impact of body mass index on graft failure and overall survival following liver transplant*
Authors: Rustgi Vinod K , Marino Gustavo , Rustgi Sheila , Halpern Michael T , Johnson Lynt B. , Tolleris Christine , Taddei Tamar H 
Published: October 2004

Abstract:  Goals:  To assess the influence of body mass index (BMI) in the outcome of liver transplantation.Background:  Body mass index appears to affect liver transplantation, independently of several risk factors.Study:  A review of the United Network for Organ Sharing database included 32 515 liver transplants from 1992 through 2000 with at least one follow‐up visit, of which 26 920 had information for determining BMI. The overall impact of elevated BMI (>25), and the impact of increasingly elevated BMI (25–40+) on graft failure rates and overall survival rates are assessed using proportional hazards regression.Results:  Controlling for follow‐up time, age, gender, race, number of comorbidities, and status 1 designation, the impact of BMI on survival was mixed. The risk of death was elevated for patients with low BMI (<19) and BMI values of ≥40. Compared with patients with BMI of 19–22, those with BMI > 25 had a decreased likelihood of death. This decrease was seen among patients with BMI of 25–34.Conclusion:  BMI did not significantly affect rates of graft failure. Compared with patients with a BMI in the ‘normal’ range, those with moderately elevated BMI had decreased likelihood of death while patients with low BMI or extremely high BMI had increased likelihood of death.
Dyslipidemia during sirolimus therapy in patients after liver transplantation
Authors: Kniepeiss D , Iberer F , Schaffellner S , Jakoby E , Duller D , Tscheliessnigg KH 
Published: October 2004

Abstract:  Introduction:  Sirolimus (SRL) is an immunosuppressive agent of potential benefit in clinical liver transplantation (LTX). One of the major side effects of SRL is hyperlipidemia, which is reported in up to 44% of patients. In this report, we describe the lipid profiles of 20 stable liver transplant recipients who received SRL for immunosuppression.Methods:  The study group received SRL in combination with tacrolimus and/or mycophenolate mofetil (MMF). The control group was administered calcineurin inhibitor (CI) and MMF. Fasting serum cholesterol level, high‐density lipoproteins (HDL) and low‐density lipoproteins (LDL) were measured regularly. Furthermore, the total cholesterol/HDL ratio and the LDL/HDL ratio were evaluated. Diabetes and hypertension were monitored as well.Results:  In the SRL group, hypercholesterolemia was found in three patients (15%) and hypertriglyceridemia in two patients (10%). There was no marked difference from the control group, although a higher association of SRL with hyperlipidemia was described in the literature. Furthermore, HDL and LDL levels were similar in both groups, as well as total cholesterol/HDL ratio and LDL/HDL ratio. Diabetes and hypertension had a similar incidence in both the groups. Thus, there was no difference concerning the cardiovascular atherosclerosis risk between the immunosuppressive protocol with SRL or with CI.Discussion:  The results of our retrospective study demonstrated that the immunosuppressive regimen can potentially influence the incidence of hyperlipidemia in patients after LTX. SRL in combination with tacrolimus and/or MMF had no higher incidence of hyperlipidemia than CI and MMF. The combination of immunosuppressive therapy with low dose and low levels of each immunosuppressive agent could decrease the risk of atherosclerosis and its complications in long‐term survivors after LTX.
Development of an unbiased method for the estimation of liver steatosis
Authors: Fiorini Ryan N , Kirtz Jeremy , Periyasamy Basker , Evans Zachary , Haines Julia K , Cheng Gang , Polito Carmen , Rodwell David , Shafizadeh Stephen F , Zhou Xin , Campbell Crystal , Birsner Jennifer , Schmidt Michael , Lewin David , Chavin Kenneth D 
Published: October 2004

Abstract: Background: Steatosis significantly contributes to an organ's transplantability. Livers with >30% fat content have a 25% chance of developing primary non‐function (PNF). The current practice of evaluating a hematoxylin and eosin (H&E) stained donor biopsy by visual interpretation is subjective. We hypothesized that H&E staining of frozen sections fails to accurately estimate the degree of steatosis present within a given liver biopsy. To address this problem of evaluating steatosis in prospective donor organs, we developed a fast, user friendly computer methodology to objectively assess fat content based on the differential quantification of color pixels in Oil Red O (ORO) stained liver biopsies.Methods: The accuracy of human visual estimation of fat content by H&E and ORO stains was compared with computer‐based measurements of the same slides from 25 frozen sections of donor biopsies.Results: Samples with a fat content >20% showed marked variation between human interpretation and computer analysis. There was also a significant difference in the human interpretation of fat based on the method of staining. This difference ranged from 3 to 37% with H&E.Discussion: Use of ORO resulted in a more consistent estimation of liver steatosis compared with H&E, but human interpretations failed to correlate with computer measurements. Such differences in fat content estimations might result in the rejection of a potentially transplantable organ or the acceptance of a marginal one. Ideally, our protocol can rapidly be applied to clinical practice for accurate and consistent measurement of fat in liver sections for the ultimate purpose of increasing the number of successful transplantable organs.