bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ontogenetic allometry and body composition of harbour porpoises (Phocoena phocoena, L.) from the western North Atlantic
Authors: McLellan W. A. , Koopman H. N. , Rommel S. A. , Read A. J. , Potter C. W. , Nicolas J. R. , Westgate A. J. , Pabst D. A. 
Published: September 2002

AbstractNorth Atlantic harbour porpoises Phocoena phocoena (L.) face considerable energetic challenges, as they are relatively small marine mammals with an intense reproductive schedule and a cold‐water habitat. Post‐natal growth of these porpoises was described using ontogenetic allometry and body composition techniques. The cross‐sectional sample contained robust calves, immature, and mature porpoises (n= 122) incidentally killed in commercial fishing operations between 1992 and 1998. Total mass and the mass of 26 body components were measured using a standard dissection protocol. Most body components grew similarly in female and male porpoises. Blubber, brain and skull were negatively allometric, while muscle and reproductive tissues exhibited positive allometry. Female heart, liver, intestine and mesenteric lymph node grew at significantly higher rates than in males. Male locomotor muscle and pelvic bones grew significantly faster than in females. High growth rates for visceral and reproductive organs in porpoises, relative to other mammals, may underlie their early maturation and support their intensive, annual reproductive schedule. Relative to other cetaceans, porpoises seem to allocate a larger percentage of their total body mass to blubber. This allocation to blubber, which is greatest in calves (37% of body mass), may provide harbour porpoises with the thermal insulation required to live in cold water. The factors influencing growth rates and differential investments in body composition seem to change at various stages of a porpoise's life. Energy allocation in porpoises seems to shift from an emphasis on developing an insulative blubber layer in young animals to preparing the body for annual reproduction at sexual maturity.
Fatty acid profiles of yolk lipids of five species of wild ducks (Anatidae) differing in dietary preference
Authors: Speake Brian K. , Surai Peter F. , Bortolotti Gary R. 
Published: September 2002

AbstractThe fatty acid compositions of yolk lipids of eggs collected in the wild from five species of ducks (Anatidae) showing a range of dietary preferences, the king eider Somateria spectabilis, the lesser scaup Aythya affinis, the mallard Anas platyrhynchos, the green‐winged teal Anas crecca and the gadwall Anas streperi, are reported. For all five species, the fatty acid profiles conformed to a similar pattern, characterized by relatively balanced proportions (w/w) of arachidonic (6.7–9.1%) and docosahexaenoic (5.9–7.0%) acids in yolk phospholipid. This contrasts markedly with the yolk phospholipid of current commercially‐reared ducks where the proportion of arachidonic acid can be 10 times greater than that of docosahexaenoic acid. It was most notable that the similarities in yolk fatty acid profiles among the different species of wild ducks were achieved despite the considerable interspecies variation in dietary modes. It seems that, in this instance, genetic factors deriving from a common phylogeny may be more important than dietary differences in determining the fatty acid composition of yolk.
A European Progressive Era?
Authors: Payre Reynaud 
Published: September 2002

Daniel T. Rodgers, Atlantic Crossings. Social Politics in a Progressive Age (Cambridge, MA: Harvard University Press, 1998), 634 pp., $36.95, ISBN 0-674-05131-9.Axel R. Schäfer, American Progressives and German Social Reform, 1875–1920 (Stuttgart: Steiner, 2000), 252 pp., €37.00, ISBN 3-515-07461-9.Nancy Stieber, Housing Design and Society in Amsterdam. Reconfiguring Urban Order and Identity, 1900–1920 (Chicago: University of Chicago Press, 1998), 386 pp., $45.00, ISBN 0-226-77417-1.Christian Topalov, ed., Laboratoires du nouveau siècle. La nébuleuse réformatrice et ses réseaux en France, 1880–1914, (Paris: Éditions de l'École des Hautes Études en Sciences Sociales, 1999), 574 pp., €38.00. ISBN 2-7132-1323-1.
A Model for Real Thermal Control in High‐Pressure Treatment of Foods
Authors: Otero Laura , Molina‐García Antonio D. , Ramos Angel M. , Sanz Pedro D. 
Published: September 2002

AbstractA model for the simulation of thermal exchanges in a complete high‐pressure equipment was developed. Good agreement between simulated and experimental time‐temperature profiles was found during different processes of pressurization and depressurization. The model allows study of the effect of different variables to improve thermal control in the treatments performed. This work involved an important advance in optimization and regulation of high‐pressure processes in the food industry.
Efficacy of a Hot Washing Process for Pretreated Yellow Poplar to Enhance Bioethanol Production
Authors: Nagle Nicholas J. , Elander Richard T. , Newman Mildred M. , Rohrback Brian T. , Ruiz Raymond O. , Torget Robert W. 
Published: September 2002

AbstractCost reductions for pretreatment and bioconversion processes are key objectives necessary to the successful deployment of a bioethanol industry. These unit operations have long been recognized for their impact on the production cost of ethanol. One strategy to achieve this objective is to improve the pretreatment process to produce a pretreated substrate resulting in reduced bioconversion time, lower cellulase enzyme usage, and/or higher ethanol yields. Previous research produced a highly digestible pretreated yellow poplar substrate using a multistage, continuously flowing, very dilute sulfuric acid (0.07% (w/v)) pretreatment. This process reduced the time required for the bioconversion of pretreated yellow poplar sawdust to ethanol. This resulted in a substantially improved yield of ethanol from cellulose. However, the liquid volume requirements, steam demand, and complexity of the flow‐through reactor configuration were determined to be serious barriers to commercialization of that process. A reconfigured process to achieve similar performance has been developed using a single‐stage batch pretreatment followed by a separation of solids and liquids and washing of the solids at a temperatures between 130 and 150 °C. Separation and washing at the elevated temperature is believed to prevent a large fraction of the solubilized lignin and xylan from reprecipitating and/or reassociating with the pretreated solids. This washing of the solids at elevated temperature resulted in both higher recovered yields of soluble xylose sugars and a more digestible pretreated substrate for enzymatic hydrolysis. Key operating variables and process performance indicators included acid concentration, temperature, wash volume, wash temperature, soluble xylose recovery, and performance of the washed, pretreated solids in bioconversion via simultaneous saccharification and fermentation (SSF). Initial results indicated over a 50% increase in ethanol yield at 72 h for the hot washed material as compared to the control (no washing, no separation) and a 43% reduction of in the bioconversion time required for a high ethanol yield from cellulose
Inhibition of Human Cell Apoptosis by Silkworm Hemolymph
Authors: Choi Shin Sik , Rhee Won Jong , Park Tai Hyun 
Published: September 2002

AbstractMany studies on preventing apoptosis have been carried out from the viewpoint of anti‐apoptotic cloned‐gene expressions inside cells, whereas in this study, we investigated the inhibition of apoptosis by the addition of silkworm hemolymph, a natural compound, from outside of the cells. In a previous study, we reported the inhibition effect of silkworm hemolymph on the baculovirus‐induced insect cell apoptosis. Using the vaccinia virus‐HeLa cell system as a model system in this study, we found that silkworm hemolymph, the insect serum, inhibits apoptosis not only in the insect cell system but also in the human cell system. The vaccinia virus‐induced HeLa cell apoptosis was analyzed using DNA electrophoresis, TUNEL, and flow cytometry, and the resulting data confirmed that silkworm hemolymph inhibits human cell apoptosis. The inhibition of apoptosis due to silkworm hemolymph was not caused by an inhibition of virus binding and internalization steps, nor did silkworm hemolymph interfere with the virus production. The inhibition of apoptosis by silkworm hemolymph decreased the cell detachment from an adhering surface. With these characteristics, silkworm hemolymph can be effectively used to minimize cell death in commercial animal cell culture.
Nonlinear Dynamics of Regulation of Bacterial trpOperon: Model Analysis of Integrated Effects of Repression, Feedback Inhibition, and Attenuation
Authors: Xiu Zhi‐Long , Chang Zeng‐Yi , Zeng An‐Ping 
Published: September 2002

AbstractThe trpoperon encodes the five genes for the enzymes required to convert chorismate to tryptophan, and its switching on and off is controlled by both feedback repression and attenuation in response to different levels of tryptophan in the cell. Repression of the operon occurs when tryptophan concentration is high, and attenuation fine‐tunes the transcription level at a lower cellular concentration of tryptophan. An extended mathematical model is established in this study to describe the switching on and off of the trpoperon by considering the integrated effects of repression and attenuation. The influences of cell growth rate on the biosynthesis of tryptophan, stability and dynamic behavior of the trpoperon are investigated. Sustained oscillations of tryptophan levels are predicted from the regulated turning on and off of the trpoperon. It is interesting to note that during such oscillations the regulation of transcription displays a kind of “on” and “off” state in terms of gene expression, indicating the existence of a genetic circuit or switch in the regulation of the trpoperon. Time lags between transcription and translation are also predicted and may explain the occurrence of such oscillation phenomenon.
Process Design for Enzymatic Adipyl‐7‐ADCA Hydrolysis
Authors: Schroën Catharina Gerarda Petronella Henrica , Nierstrasz Vincent Adriaan , Bosma Rouke , Dijkstra Zwaantje Johanna , VandeSandt Emilius Johannes Albertus Xavierius , Beeftink Hendrik Harmen , Tramper Johannes 
Published: September 2002

AbstractAdipyl‐7‐ADCA is a new source for 7‐aminodeacetoxycephalosporanic acid (7‐ADCA), one of the substrates for antibiotics synthesis. In this paper, a novel process for enzymatic 7‐ADCA production is presented. The process consists of a reactor, a crystallization step, a membrane separation step, and various recycle loops. The reactor can either be operated batch‐wise or continuously; with both types of processing high yields can be obtained. For batch reactors chemical degradation of 7‐ADCA can be neglected. For continuous reactors, chemical stability of 7‐ADCA is a factor to be taken into account. However, it was shown that the reaction conditions and reactor configuration could be chosen in such a way that also for continuous operation chemical degradation is not important. Downstream processing consisted of crystallization of 7‐ADCA at low pH, followed by a nanofiltration step with which, at low pH, adipic acid could be separated from adipyl‐7‐ADCA and 7‐ADCA. The separation mechanism of the nanofilter is based on size exclusion combined with charge effects. Application of this filtration step opens possibilities for recycling components to various stages of the process. Adipic acid can be recycled to the fermentation stage of the process while both adipyl‐7‐ADCA and 7‐ADCA can be returned to the hydrolysis reactor. In this way, losses of substrates and product can be minimized.
Mass Transfer and Hydrocarbon Biodegradation of Aged Soil in Slurry Phase
Authors: García‐Rivero M. , Saucedo‐Castañeda G. , de Hoyos S. Flores , Gutiérrez‐Rojas M. 
Published: September 2002

AbstractAddition of toluene into slurry phase laboratory microcosm is proposed in order to increase desorption rate of hydrocarbons and as an alternative to improve bioavailability of hydrocarbon in aged soils. Our studies showed that toluene has a positive effect on desorption of total petroleum hydrocarbons (TPH). Addition of 14 000 mg toluene/kg of soil, in highly polluted soil, increased the consumption rate of hydrocarbons three times in comparison to control without solvent. In 30 days the initial TPH concentration in soil, 292 000 mg/kg, diminished 45%. Although toluene was able to dissolve complex organic compounds such as asphaltene fraction, it probably yielded a highly toxic toluene‐hydrocarbons phase. The inhibitory effect of toluene‐TPH was also studied. A substrate inhibition model was used: the kmand kiconstants were 57 and 490 mg TPH/L liquid phase, respectively. Experimental data were well described when the proposed model included sequential desorption and biodegradation phenomena. Damköhler number evaluation showed that rate of mass transfer was the limiting step in overall biodegradation in nonsolvent control. When high concentration of toluene was added, then bioreaction was the limiting step, but inhibitory effect should be considered. However, toluene addition at low concentrations facilitates the biodegradation of aromatic compounds.
Ultrasound‐Induced Stress Responses of Panax ginsengCells: Enzymatic Browning and Phenolics Production
Authors: Wu Jianyong , Lin Lidong 
Published: September 2002

AbstractThe stress metabolic activities of Panax ginseng( P. ginseng) cells induced by low‐energy ultrasound (US) were examined. P. ginsengcells in suspension cultures were exposed to 38.5 kHz US at two power levels (power density 13.7 and 61 mW/cm3) for 2 min. The US treatment caused rapid increase in the intracellular levels of polyphenol oxidase (PPO), peroxidase (PO), and phenylalanine ammonia lyase (PAL) and the production of polyphenols (PP) and phenolic compounds. The US‐induced enzyme activities and phenolics production are part of plant stress responses to a mechanical stimulus. The much higher PPO activity and rate of PP production in the sonicated cultures are correlated to enzymatic browning, suggestive of physical damage and membrane permeabilization of the cells by US. The cells after sonication also showed decreased water content and cell volume, which may also be attributed to US‐induced cell membrane permeabilization and water release. High‐pressure shock and fluid shear stress arising from acoustic cavitation were regarded as the major causes of the responses. Nevertheless, the US exposure caused only temporary cell growth depression but no net loss of biomass yield of the culture.
Carbon cash crop
Authors: Showstack Randy 
Published: September 2002

Farms produce significant amounts of methane and nitrous oxide, and lesser amounts of carbon dioxide, all of which are greenhouse gases. A new publication from the U.S. Department of Agriculture (USDA) highlights measures some farmers already are taking to reduce greenhouse gases, and says that growing carbon as a crop can help farmers as well as the climate.The report, “Growing Carbon,” says that providing credits to agricultural producers who increase their stores of carbon in the soil or in trees could be one way for countries to reduce carbon dioxide in the atmosphere and meet greenhouse gas emissions targets under potential domestic legislation or international climate agreements, such as the 1997 Kyoto Protocol.
USGS maps arsenic concentrations
Authors: Showstack Randy 
Published: September 2002

About 10% of U.S. groundwater samples analyzed as part of a new U.S. Geological Survey (USGS) study exceed the World Health Organization's (WHO) guideline for arsenic in drinking water.A USGS map of arsenic concentrations in groundwater across the U.S., released on May 8, shows the highest concentrations were found in samples taken from states in the Southwest and Rocky Mountain region, as well as in sections of the Midwest and Northeast.
Bids requested for Genesis Mission analytical facilities
Authors: Burnett Donald S. 
Published: September 2002

The Genesis Discovery mission, to be launched in January 2001, will expose ultrapure materials to the solar wind for about 2 years and then return this sample to Earth for isotopic and chemical analysis in terrestrial laboratories.Sample return missions use the best available instrumentation to achieve mission science goals. To complete the Genesis science objectives, advanced instrumentation that surpasses present laboratory sample analysis capabilities is required. Advanced Analytical Instrumentation Facilities (AAIFs) will be created for the mission to ensure that the best analytical instruments are used. This approach also enables broad participation by NASA scientists in solar wind sample return analysis.
Elastic thickness of the lithosphere in the Central Canadian Shield
Authors: Wang Yihua , Mareschal Jean‐Claude 
Published: September 2002

We have used the coherence between Bouguer gravity and topography to determine the elastic thickness (Te) of the lithosphere in central Canada. In order to improve the resolution, we have estimated the spectra with the maximum entropy method. The variations in elastic thickness delineate three main regions: (1) The Interior Platform where Te varies between 25 and 50 km; (2) The Shield includes several high rigidity cores, in particular in the Trans‐Hudson orogen and in the Hearne Province where Te >80 km; (3) The Hudson Bay basin has an elastic thickness between 50 and 70 km with higher values in the eastern part.The results suggest that Te is controlled by the thermal regime in the platform. There is no difference in Te between the Proterozoic and Archean Provinces of the Shield. In the platform, the elastic thickness is lowest where sediments are thickest, indicating that low rigidity has amplified the subsidence of the basin.
Outstanding student paper awards
Authors: Anonymous  
Published: September 2002

The Hydrology Section presented five outstanding student paper awards at the 1999 Spring Meeting in Boston, Massachusetts, last June.Maneesha Joshi presented a poster titled “Estimation of the Extent and Duration of Melt on the Greenland Ice Sheet using an Edge Detection Technique on Passive Microwave Data.” She received her B.Tech. in civil engineering from the Indian Institute of Technology, Bombay in 1991, and a M.S. in environmental engineering from State University of New York, Buffalo in 1994. Maneesha expects to complete her Ph.D. in civil engineering (remote sensing) in September 1999, under the supervision of Carolyn Merry (Department of Civil and Environmental Engineering & Geodetic Science), Ken Jezek, and John Bolzan (Byrd Polar Research Center) at the Ohio State University, Columbus, Ohio. Her thesis focuses on estimating the extent of melt, melt season, and duration, and absorbed radiation on the Greenland ice sheet from passive microwave and SAR data. Maneesha's other interests include image processing, issues related to global climate change, and photogrammetry.
Tides: A Scientific History
Authors: Agnew Duncan 
Published: September 2002

If you ask most oceanographers what a Proudman function or a Doodson number is, you are likely to be met with blank looks—and yet these are terms central to the oldest concern of oceanography, the tides. Indeed, at one time tidal science was sufficiently prominent that those who studied it were called “tidalists,” a term coined by the same person (William Whewell) who invented the term “scientist,” and who was himself a tidalist.The long and varied history of this part of geophysics has been examined by its leading expert, David Cartwright, in a narrative that extends from ancient Greek and Chinese ideas (already based on an impressive amount of empirical knowledge) to the latest results from satellite altimetry. As Cartwright points out, satellite data have essentially solved the long‐standing problem of mapping the global ocean tides, and thus have in some ways brought tidal studies, if not to an end, to a point from which a retrospective look is appropriate.
Assembly fetes world climate research area and its leader
Authors: McGuffie Kendal 
Published: September 2002

Both a relatively new world‐climate research area and a person instrumental in bringing it about were feted at the International Union of Geodesy and Geophysics (IUGG) Assembly this past July. The research area has been embodied in the Project for Intercomparison of Land‐Surface Parameterization Schemes (PILPS), which actually began in 1992. Its leader, Ann Henderson‐Sellers, was awarded a doctor of science degree in recognition of her 21 years of work in climate model predictions.Said Henderson‐Sellers: “I am very pleased to be able to look back on an era in which this discipline's research develops from the simplest conceivable land‐surface scheme, literally a hole in the soil, to today's highly complex schemes, which include leaves, stomates, roots, and even ecological transitions.”
Advances in varved sediment studies help paleoclimate reconstructions
Authors: Francus Pierre , Saarinen Timo 
Published: September 2002

Recent interest in varved sediments has expanded considerably, since they can provide an accurate chronology for paleoclimatic reconstruction and can be found in various environments around the globe. A varve is a lamina or a sequence of laminae deposited in a body of still water within a year's time. Proxy data, such as pollen, diatoms, stable isotope geochemistry and microchemical analysis, retrieved from such laminated records can be temporarily constrained. Also, the varves themselves contain climatic information.Generally in order to validate climate models, especially in terms of their ability to simulate short‐term environmental changes such as El Niño, it is important to test them against the past climate record. Such testing is usually restricted to instrumental climate data. However, high‐resolution records (such as tree rings, banded corals, and ice cores, as well as varved sediments) can provide annually resolved paleoclimatic information for longer periods of time.
New seismic study of deep sea gas hydrates results in greatly improved resolution
Authors: Gettrust J. , Wood W. , Lindwall D. , Chapman R. , Walia R. , Hannay D. , Spence G. , Louden K. , MacDonald R. , Hyndman R. D. 
Published: September 2002

A multichannel seismic survey has resulted in greatly improved resolution of structural details of deep sea gas hydrates off the west coast of Canada, revealing numerous geological features not before evident. The survey using the Naval Research Laboratory deep‐towed acoustic/geophysics system (DTAGS), provided high‐resolution images and layer velocities more than 10 times better than those obtained in the past using conventional systems. Vertical resolution within 2 m and horizontal resolution within 20 m were achieved.The work demonstrates that high‐resolution seismic surveys with deep towed multichannel systems can provide important new information about pathways of fluid and gas migration that control the formation of gas hydrates. Conventional surface‐towed seismic systems are unable to do this.