bluuebunny/crossref_metadata_2025 huggingface dataset:
Non‐linear optics on an exciton state in a single quantum dot
Authors: Melet Romain , Grousson Roger , Voliotis Valia , Wang Xue‐Lun
Published: April 2008

We report on non‐linear effects on the exciton ground state in a single quantum dot, driven by a strong resonant optical field. The resonant excitation is achieved by embedding the quantum dots in a waveguiding structure. Thus, the light–matter coupling is enhanced, allowing the observation of Rabi oscillations up to three periods. With increasing pulse area, a decrease of the exciton lifetime is observed leading to a very rapid damping of the oscillations amplitude. Resonant coherent control experiments show that the coherence time of the ground exciton state in a single quantum dot is fast, of the order of a few tens of picoseconds. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ultrafast tailoring of the exciton distribution in quantum wells
Authors: Amo A. , Ballarini D. , Kozhemyakina E. , Sanvitto D. , Kłopotowski Ł. , Viña L. , Bajoni D. , Bloch J. , Skolnick M. S. , Roberts J. S.
Published: April 2008

By excitation with two, consecutive, picosecond pulses we demonstrate that the distribution and temperature of a photocreated exciton population in semiconductor quantum wells can be dynamically tailored. The changes in the exciton distribution result in abrupt alterations of the photoluminescence dynamics, in particular in the appearance of a sudden decrease in the heavy‐hole excitonic emission when the second pulse impinges upon the sample. We present a quasi‐equilibrium thermodynamical model that includes the energy distribution of excitons and electron–hole plasma, which quantitatively accounts for the sharp dips observed in the exciton emission dynamics. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Neutron diffraction and magnetization measurements on CeNi4.2Mn0.8 and Y0.7Ni4.2Mn0.8
Authors: Toliński T. , Kaczorowski D. , Kowalczyk A. , Hoser A. , Stüßer N. , Talik E. , Klimczak L. M.
Published: April 2008

The cubic CeNi4Mn compound has been claimed to show a large spin‐polarization, magnetic moment and a high Curie temperature. To verify these properties we have carried out the magnetometric and neutron diffraction experiments on the nominally polycrystalline CeNi4Mn and YNi4Mn compounds. The real stoichiometry was estimated based on X‐ray photoemission and neutron diffraction as CeNi4.2Mn0.8 and Y0.7Ni4.2Mn0.8. The magnetic properties of Y0.7Ni4.2Mn0.8 have been studied with neutron diffraction to investigate the role of the rare earth in CeNi4.2Mn0.8. We have found that the samples crystallize in the hexagonal CaCu5‐type of structure. The deviation from the cubic structure is ascribed to the presence of a small nonstoichiometry. These structural changes are accompanied by a drop of the magnetic parameters. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ginkgo biloba extract improves coronary artery circulation in patients with coronary artery disease: contribution of plasma nitric oxide and endothelin‐1
Authors: Wu Yu‐Zhou , Li Shu‐Qin , Zu Xiu‐Guang , Du Jun , Wang Feng‐Fei
Published: April 2008

In patients with coronary artery disease (CAD), coronary blood flow is usually impaired due to imbalanced vasoactive substances such as nitric oxide (NO) and endothelin‐1 (ET‐1). The study was designed to test the effects of Ginkgo biloba extract (GBE) on the distal left anterior descending coronary artery (LAD) blood flow and plasma NO and ET‐1 levels. Eighty CAD patients were randomly assigned to GBE (n = 42) and control (n = 38) groups. The LAD blood flow was assessed non‐invasively using Doppler echocardiography at baseline and after 2 weeks. GBE treatment demonstrated a significant improvement in maximal diastolic peak velocity (MDPV), maximal systolic peak velocity (MSPV) and diastolic time velocity integral (DTVI) compared with controls (14.61 ± 4.51% vs 0.67 ± 2.66%, 9.03 ± 4.81% vs 0.34 ± 2.67% and 14.69 ± 5.08% vs 0.68 ± 3.00%, respectively, p < 0.01). NO was increased by 12.42% (p < 0.01), whereas ET‐1 was decreased by 5.82% (p < 0.01). The NO/ET‐1 ratio was increased by 19.47% (p < 0.01). A linear correlation was confirmed between the percentage change in LAD blood flow and in NO, ET‐1 or NO/ET‐1 ratio following GBE treatment. The results suggest that GBE treatment in CAD patients led to an increase of LAD blood flow, which might at least be related partly to the restoration of the delicate equilibrium between NO and ET‐1. Copyright © 2008 John Wiley & Sons, Ltd.
Acanthopanax senticosus suppresses reactive oxygen species production by mouse peritoneal macrophages in vitro and in vivo
Authors: Lin Qiu‐Ye , Jin Li‐Ji , Cao Zhen‐Hui , Lu Ya‐Nan , Xue Hong‐Yu , Xu Yong‐Ping
Published: April 2008

Excess production of reactive oxygen species by macrophages has been implicated in many inflammatory diseases. The present study investigated the inhibitory effect of the stem bark extract of Acanthopanax senticosus on the production of superoxide anion and hydrogen peroxide in mouse peritoneal macrophages in vitro and in vivo. Exposure of mouse peritoneal macrophages to A. senticosus extract significantly suppressed superoxide anion production induced by zymosan in a dose‐dependent manner. Similarly, exposure of mouse peritoneal macrophages to A. senticosus extract significantly inhibited hydrogen peroxide production induced by phorbol 12‐myristate 13‐acetate (PMA) in a dose‐dependent manner. Intraperitoneal administration of A. senticosus extract to KM mice reduced the ex vivo production of zymosan induced‐superoxide anion and PMA‐induced hydrogen peroxide by their peritoneal macrophages. Exposure to A. senticosus extract did not affect the cell viability or systemic toxicity. A. senticosus inhibited reactive oxygen species production by mouse peritoneal macrophages in vitro and in vivo and may be partly responsible for the antiinflammatory function. Copyright © 2008 John Wiley & Sons, Ltd.
Large old trees influence patterns of δ13C and δ15N in forests
Authors: Weber Pascale , Bol Roland , Dixon Liz , Bardgett Richard D.
Published: April 2008

Large old trees are the dominant primary producers of native pine forest, but their influence on spatial patterns of soil properties and potential feedback to tree regeneration in their neighbourhood is poorly understood. We measured stable isotopes of carbon (δ13C) and nitrogen (δ15N) in soil and litter taken from three zones of influence (inner, middle and outer zone) around the trunk of freestanding old Scots pine (Pinus sylvestris L.) trees, to determine the trees' influence on below‐ground properties. We also measured δ15N and δ13C in wood cores extracted from the old trees and from regenerating trees growing within their three zones of influence. We found a significant and positive gradient in soil δ15N from the inner zone, nearest to the tree centre, to the outer zone beyond the tree crown. This was probably caused by the higher input of 15N‐depleted litter below the tree crown. In contrast, the soil δ13C did not change along the gradient of tree influence. Distance‐related trends, although weak, were visible in the wood δ15N and δ13C of regenerating trees. Moreover, the wood δ15N of small trees showed a weak negative relationship with soil N content in the relevant zone of influence. Our results indicate that large old trees control below‐ground conditions in their immediate surroundings, and that stable isotopes might act as markers for the spatial and temporal extent of these below‐ground effects. Copyright © 2008 John Wiley & Sons, Ltd.
Assessing morphologic complexity and diversity in river systems using three‐dimensional asymmetry indices for bed elements, bedforms and bar units
Authors: Rayburg Scott C. , Neave Mel
Published: April 2008

Geomorphologists are becoming increasingly interested in assessing morphologic structure and the diversity and/or complexity in morphologic structure across multiple scales within river systems. Unfortunately, many of our existing tools/variables are unsuitable for this task because they do not work across multiple scales or with changing discharges. Asymmetry is one variable that can be used to either include or exclude variations in flow stage and that can be assessed across multiple scales. Existing asymmetry indices, however, are limited in scope and largely focus on only cross‐sectional form. This study examines three existing asymmetry indices in the cross‐stream and downstream planes (for cross‐sections and riffle or pools, respectively) and develops nine new asymmetry indices that incorporate vertical, cross‐stream and downstream asymmetry for bed elements (e.g. riffle crests, pool troughs, riffle entrance slope), bedforms (pools or riffles) and bar units (pool‐riffle sequences) to investigate the utility of asymmetry as a measure of morphologic structure and diversity in fluvial systems. These 12 indices are field tested on the Embarras River in East Central Illinois, USA. The results of this study indicate that there is considerable morphologic diversity in bed elements, bedforms and bar units both at bankfull and also with varying flow stage. This multi‐scale, multidimensional, multistage variability in morphologic structure highlights the complexity of natural river systems. The highly variable nature of fluvial form within a reach has important implications for river restoration and/or assessments of physical habitat or river health especially in instances where pools, riffles or pool‐riffle sequences are the focus of study. In general the most robust and useful combination of asymmetry indices for most applications includes A* and AL1 for bed elements and bedforms and AL3, AW and AH for bar units. Copyright © 2008 John Wiley & Sons, Ltd.
Response of macroinvertebrate and diatom communities to human‐induced physical alteration in mountain streams
Authors: Bona Francesca , Falasco Elisa , Fenoglio Stefano , Iorio Luca , Badino Guido
Published: April 2008

It is generally argued that epilithic diatoms and macroinvertebrates are highly sensitive to changes in water quality, while only a few studies have been conducted on their response to physical disturbance. The main purpose of this research is to investigate whether these two communities respond to physical river disturbance like banks, substrate and flux alteration induced by human action.

We sampled 12 high‐altitude streams in the Gran Paradiso National Park, a protected area where the main human activities are limited to hiking and high‐altitude pasture. The sampled stretches of the rivers were characterized with respect to their geomorphological features and possible human modifications. Water uptake for power supply, riverbed and bank modifications represented the main human activities which could determinate alterations in community structure and composition. Habitat structure was evaluated using the Southern European River Habitat (RHS–SE), while the biological status of the river has been estimated by means of the following biotic and diatomic indices: IBE, BMWP, ASPT, Ephemeroptera, Plecoptera and Trichoptera families (EPT) for macroinvertebrates, EPI‐D, IBD and IPS for diatoms. A general concordance between chemical parameters and structure of biological communities was observed. On the other hand, the RHS–SE highlighted the main geomorphological features and detected some slight physical alterations, as quantified by the indices Habitat Modification Score (HMS) and Habitat Quality Assessment (HQA). In short, our findings demonstrate that morphological alterations, even if slight, affect biological diversity and the presence of some specific taxa, while biological indices are independent of the level of physical modifications. Copyright © 2008 John Wiley & Sons, Ltd.
Effects of residence time on summer nitrate uptake in mississippi river flow‐regulated backwaters
Authors: James William F. , Richardson William B. , Soballe David M.
Published: April 2008

Nitrate uptake may be improved in regulated floodplain rivers by increasing hydrological connectivity to backwaters. We examined summer nitrate uptake in a series of morphologically similar backwaters on the Upper Mississippi River receiving flow‐regulated nitrate loads via gated culverts. Flows into individual backwaters were held constant over a summer period but varied in the summers of 2003 and 2004 to provide a range of hydraulic loads and residence times (τ). The objectives were to determine optimum loading and τ for maximum summer uptake. Higher flow adjustment led to increased loading but lower τ and contact time for uptake. For highest flows, τ was less than 1 day resulting in lower uptake rates (Unet < 300 mg m−2 day−1), low uptake efficiency (U% < 20%) and a long uptake length (Snet > 4000 m). For low flows, τ was greater than 5 days and U% approached 100%, but Unet was 200 mg m−2 day−1. Snet was < half the length of the backwaters under these conditions indicating that most of the load was assimilated in the upper reaches, leading to limited delivery to lower portions. Unet was maximal (384–629 mg m−2 day−1) for intermediate flows and τ ranging between 1 and 1.5 days. Longer Snet (2000–4000 m) and lower U% (20–40%) reflected limitation of uptake in upper reaches by contact time, leading to transport to lower reaches for additional uptake. Uptake by ∼10 000 ha of reconnected backwaters along the Upper Mississippi River (13% of the total backwater surface area) at a Unet of ∼630 mg m−2 day−1 would be the equivalent of ∼40% of the summer nitrate load (155 mg day−1) discharged from Lock and Dam 4. These results indicate that backwater nitrate uptake can play an important role in reducing nitrate loading to the Gulf of Mexico. Copyright © 2008 John Wiley & Sons, Ltd.
Hydrologic alterations in the Wabash River watershed, USA
Authors: Pyron Mark , Neumann Klaus
Published: April 2008

Flow alteration of streams from anthropogenic impacts is ubiquitous worldwide. In this paper, we examine flow alteration in a single watershed, the Wabash River and suggest potential impacts on aquatic assemblages. The Indicators of Hydrologic Alteration (IHA) software was used to evaluate hydrological variables generated from daily discharge data of 80 USGS gauging stations, during the past several decades. We used the approach of regressions of hydrological variables against time to identify hydrologic change. An average of 6.9 hydrologic variables (of 33 variables) were significantly altered at each station, and stations with larger watersheds had an increased number of altered variables. A principal components (PC) analysis of altered hydrologic variables resulted in three of four PC axes that were correlated with watershed area. Significant results were: (1) larger streams were more likely to have hydrologic alteration than smaller streams; (2) streams with upstream dams had increased minimum flows for 1‐, 3‐, 7‐ and 30‐day intervals, decreased maximum flows for 1‐, 3‐, 7‐ and 30‐day intervals, increased fall rates, decreased summer monthly flows and decreased high pulse counts; (3) the presence of agriculture in upstream watersheds resulted in an increased number of zero flow days, increased low pulse counts and decreased high flows during October and April. No significant differences were detected in hydrologic alteration based on urban land‐use of upstream watersheds. Hydrologic alterations in the Wabash River watershed have undoubtedly resulted in ecological degradation. We suggest that changes in assemblages during the past century are linked to these hydrologic alterations. Copyright © 2008 John Wiley & Sons, Ltd.
Civil Rights Legislation and the Housing Status of Black Americans: An Overview
Authors: Leigh Wilhelmina A.
Published: April 2008

This article explores the relationship between civil rights legislation and the housing status of black Americans. An economic and judicial history of the pursuit of fair housing (or equal opportunity in access to housing) is provided for two major periods—from the late 1800s to the 1950s, and from the years of the civil rights movement to the present. An exploration of the housing status of black Americans throughout these periods follows, in which measures such as crowdedness and tenure—attributable partly to inequality in access to housing—are examined, and comparisons of black and whites are made.
Trends in the Housing Status of Black Americans across Selected Metropolitan Areas
Authors: Leigh Wilhelmina A.
Published: April 2008

This article examines housing data for a set of metropolitan areas and their central cities, and explores the major issues that arise when considering the impacts by race of federal housing assistance programs. Housing market conditions and characteristics vary widely by race across the areas covered—Birmingham, AL; Buffalo, NY; Cleveland, OH; Indianapolis, IN; Memphis, TN; Milwaukee, WI; Newport News, VA; Oklahoma City, OK; Providence, RI; Salt Lake City, UT; and San Jose, CA. Issues related to racial impacts of federal housing assistance emanate from two major policy goals—to help low-income households and to provide equal housing opportunity.
Racial Disparity in the Atlanta Housing Market
Authors: Robinson Carla J.
Published: April 2008

Atlanta has the reputation of being a city of opportunity for blacks. However, in Atlanta, as well as in other cities across the nation, the nexus of racism and economic discrimination has resulted in disparities between the housing status of blacks and whites. This article examines racial disparities in the Atlanta housing market. It begins by tracing recent trends in the Atlanta-area economy and by providing background information on the local housing market. It then discusses the roles of the federal Home Mortgage Disclosure Act of 1975 and Community Reinvestment Act of 1977 in the efforts of local groups to reduce racial disparities in the housing market. The final section discusses recent local developments that might lead to improvements in the housing status of black Atlantans.
Urban Renewal: The Case of Buffalo, NY
Authors: Price Alfred D.
Published: April 2008

Scholars of urbanism have long been critical of America's post-World War II efforts at urban renewal. What is generally less well understood is the theoretical context out of which urban renewal policy arose.

This analysis sets forth the key precepts of modernist thinking in city planning as the explanation for urban renewal's policy miscalculations. Data for Buffalo document the case, with emphasis upon the exclusion of blacks in the redevelopment process.

Following three decades of failure, 1950 to 1980, a neighborhood-based renewal project is now showing promise in meeting the housing needs of inner-city black households.
Public Housing in Charlottesville: The Black Experience in a Small Southern City
Authors: Harris William M. , Olmsted Nancy
Published: April 2008

The history and public policies related to the public housing program are presented within the context of a small southern city, Charlottesville, Virginia. Consistent with the stormy beginnings of public housing nationally, the article reveals that the early days of the program in Charlottesville also were troubled. City policies to affect the residential mix of housing are shown to have limited the quality of affordable housing available to the poor and especially to low-income blacks. Programs designed by the city to overcome some of these disadvantages through both home ownership and renting also are discussed.
Recent Changes in the Housing Status of Blacks in Los Angeles
Authors: Grigsby J. Eugene , Hruby Mary L.
Published: April 2008

In the aftermath of reductions in federal housing assistance programs during the 1980s, many cities are experiencing severe shortages of affordable housing. It is particularly difficult for low income and minority households to find and maintain adequate, low-cost housing.

This article describes how Los Angeles has responded to this need through implementation of a particular housing policy and financing strategy. It specifically examines what impacts this program has had in producing affordable housing in the city's low-income, minority neighborhoods. Recommendations for further public action on housing needs in Los Angeles are also offered.
Isomerization during hydrogenation. V. Methylcis 6‐,cis 9‐,cis 12‐octadecenoates
Authors: Allen R. R.
Published: April 2008

The partial hydrogenation of mixtures of methylcis 6‐,cis 9‐ andcis 12‐octadecenoates followed by the determination of the unreacted monoenes indicated the double bonds in these positions are hydrogenated at the same rates. However, study of a hydrogenation under high isomerization conditions indicated the double bonds very near the carboxyl hydrogenate faster than those near the terminal methyl.
Physical properties of fatty acid methyl esters. IV. Ultrasonic sound velocity
Authors: Gouw T. H. , Vlugter J. C.
Published: April 2008

The ultrasonic sound velocity of the unsaturated fatty acid methyl esters from acetate to nonadecanoate, methyl oleate, linoleate, linolenate, and erucate have been measured at 20C and 40C in the liquid state. Data of the saturated compounds were correlated with the Smittenberg relation and a reasonable fit was noted. The molar sound velocity according to Rao was computed from the observed values and increments for the CH2 group and for the double bond are presented.
Exploitation of the selectivity of various chromatographic techniques for the study of the triglyceride structure of natural fats
Authors: McCarthy M. J. , Kuksis A.
Published: April 2008

The separation of naturally occurring triglyceride mixtures on the basis of mol wt, polarity, and iodine number by the methods of gas‐liquid, liquid‐liquid, and thin‐layer chromatography, respectively, rarely results in fractions representing pure triglycerides. Furthermore, most of the fractions obtained are too complex for detailed structural analyses. An integrated system using all three of these techniques for a sequential fractionation and isolation of triglyceride groups of progressively decreasing complexity, however, while not yielding single glycerides, can provide practical information for the assignment of structures. Since the possibility of the same components overlapping in all three systems is very small, a prudent application of these techniques affords triglyceride groups that can be analyzed meaningfully by enzymatic methods, and, in many cases, can lead to a complete assessment of the triglyceride structure of the mixture.

For an examination of the scope of this integrated analytical system, selected naturally occurring triglyceride mixtures were used as models. The success of the system rests upon accurate quantitative determination of the fatty acids and triglycerides by gas chromatography.
Factors affecting the rate of deterioration in the frying quality of fats II. Type of heater and method of heating
Authors: Rock S. P. , Roth H.
Published: April 2008

Using a commercially prepared hydrogenated lard and heating methods simulating those currently employed in commercial fryers, it was found that the rate of fat deterioration varied inversely with the temp of the heating element. This has been attributed to differences in the rate and duration of convection circulation, a measure of the amt of fat‐air contact, and therefore, thermal oxidation. When element temp were increased from 900舑2400F, while thermostatically maintaining the fat temp at 375F, it was found that the rate of convection circulation increased while the duration of convection circulation decreased, and it is postulated that the overall effect of increasing element temp is one of decreasing the total amt of fat contact with the air.

It was also demonstrated that mechanical circulation of fat, as required in an externally heated fat system, significantly increased that rate of fat deterioration when compared to fat heated by conventional direct gas‐heat, if both were heated and maintained at 375F for identical periods of time.
Synthesis of triglycerides from fish oil fatty acids
Authors: Lehman L. W. , Gauglitz E. J.
Published: April 2008

The generally accepted methods for the synthesis of triglycerides are unsatisfactory when they are applied to highly unsaturated systems such as those present in fish oil. The methods either fail to g ive sufficiently high yields, or they are prohibitive in cost when applied to large scale production. Of the numerous reactions studied, the most feasible was the zinc‐catalyzed esterification of fish oil fatty acids with glycerol. Thinlayer chromatography (TLC) showed that this reaction gave yields of 75舑78% triglycerides. Gas‐liquid chromatography (GLC) demonstrated the composition of the triglycerides was essentially the same as that of the original fatty acids.
Efficient production of biosynthetically labeled fatty acids
Authors: Mounts T. L. , Dutton H. J.
Published: April 2008

By short‐term exposure of a photosynthesizing oilseed plant at seed‐setting stage to high levels of C14O2, radioactivity is efficiently incorporated into glycerides yielding randomly labeled fatty acids of high specific activity.
Further observations on the 2‐thiobarbituric acid method for the measurement of oxidative rancidity
Authors: Yu T. C. , Sinnhuber R. O.
Published: April 2008

The validity of the 2‐thiobarbituric acid (TBA) procedure for the measurement of oxidative rancidity by the determination of malonaldehyde (MA) as the red pigment with an absorption max at 532 mƁ has been questioned [J. Am. Oil Chem. Soc.39, 34 (1962)]. Side reactions were reported to occur yielding degradation of TBA to products which absorb at the same wave length as the TBA‐MA complex and at 450 mƁ.

Results reported in the present paper stress the importance of reagent purification. Little or no decomposition of TBA to produce interfering colors was found after heating with acids, oxidizing agents or hydroperoxides.
Degradation of monocarbonyls from autoxidizing lipids
Authors: Lillard D. A. , Day E. A.
Published: April 2008

Abstracts

In an attempt to account for carbonyls found in oxidized lipid systems, but not theoretically predicted from the decomposition of lipid hydroperoxides, a member from each of the monocarbonyl classes commonly observed in oxidizing lipids was oxidized at 45C in a Warburg apparatus and the carbonyl products studied. The carbonyl compounds used weren‐nonanal,n‐non‐2‐enal,n‐hepta‐2,4‐dienal andn‐oct‐1‐en‐3‐one. Nonanal was relatively stable to oxidation and was oxidized to nonanoic acid. Oct‐1‐en‐3‐one did not absorb oxygen during a 52‐hr period; however, the unsaturated aldehydes oxidized at faster rates than methyl linoleate or linolenate. Non‐2‐enal upon absorption of 0.5 mole of oxygen was oxidized almost quantitatively to non‐2‐enoic acid. Hepta‐2,4‐dienal was polymerized at 0.5 mole of oxygen uptake. In addition both of the unsaturated aldehydes produced shorter chain mono‐ and dicarbonyls as oxidative degradation products. The identification of these compounds helps to explain the presence of carbonyls in oxidizing lipids and model systems that are not accountable through the decomposition of theoretically predictable isomeric hydroperoxide esters. The relatively large yield of malonaldehyde from the oxidized dienal suggests that these carbonyls may serve as a major source of malonaldehyde in oxidizing diene esters. Significant quantities of malonaldehyde are not observed in methyl linoleate until late stages of oxidation, and the dienals formed through degradation of primary hydroperoxides may in turn oxidize to give malonaldehyde.
Identification of surface active agents in admixture by thin layer chromatography
Authors: Desmond C. T. , Borden W. T.
Published: April 2008

The qualitative identification of the surface active agents commonly used in household detergent formulations is possible using thin layer chromatography (TLC). Successful separations have been made when the samples are spotted on Aluminum Oxide G and developed with isopropanol. A variety of specific reagents may be used to color the spots and thereby supplement the Rf values as a means to identify the surfactants. The analysis can be made semi‐quantitative if the separations are made using an aluminum oxide column and collecting and fractions eluted with isopropanol and methanol.
Methanesulfonic acid‐catalyzed additions IV. Additions to methyl linoleate
Authors: Eisner Abner , Perlstein Theodore , Ault W. C.
Published: April 2008

Varied aromatic compounds including phenol,o‐chlorophenol, 2‐naphthol, resorcinol, methyl salicylate, anisole, phenetole,p‐toluenethiol,p‐chlorobenzenethiol and 2‐napthalenethiol were added to methyl linoleate. Using methanesulfonic acid as a solvent‐catalyst the additions took place as readily as to oleic acid in previous experiments. The recovery of mono‐adducts, however, was complicated by the presence of di‐adducts and presumably polymeric material.

As observed in the earlier oleic acid studies, evidence for the formation of ether intermediates was obtained. The only identified products from arylthiol additions were thioethers.
Nuclear functions in space and time: Gene expression in a dynamic, constrained environment
Authors: Trinkle-Mulcahy Laura , Lamond Angus I.
Published: April 2008

All eukaryotic cells enclose their genome within a dedicated, membrane‐bound organelle termed the nucleus, which functions to partition gene transcription from sites of protein translation in the cytoplasm. Despite a great deal of research effort, basic questions about chromosome structure and gene expression mechanisms remain to be answered, including the relationship between the spatial organization of the genome and the transcription machinery. Powerful in vivo approaches are allowing researchers to test established in vitro concepts within the dynamic cellular environment, while genome‐wide screens have enabled rapid high throughput analyses of both structural and functional parameters. In several cases, as highlighted here, this has turned up surprising results and has forced a re‐evaluation of models for nuclear structure and gene regulation.
Dissociation of superoxide production by mitochondrial complex I from NAD(P)H redox state
Authors: Lambert Adrian J. , Buckingham Julie A. , Brand Martin D.
Published: April 2008

The relationship between the rate of superoxide production by complex I and NAD(P)H redox state was investigated in rat skeletal muscle mitochondria. A high rate of superoxide production was observed during succinate oxidation; the rate during pyruvate oxidation was over fourfold lower. However, the NAD(P)H pool was significantly less reduced during succinate oxidation than during pyruvate oxidation. We conclude that there is no unique relationship between superoxide production by complex I and the reduction state of the NAD(P)H pool. Our data suggest that less than 10% of the superoxide originates from the flavin site during reverse electron transport from succinate.
Use of contrast ultrasonography in the diagnosis of metastatic feline visceral haemangiosarcoma
Authors: Webster Natalie , Holloway Andrew
Published: April 2008

A 12-year-old cat was presented for investigation of weight loss and inappetence. Radiography and conventional grey-scale ultrasonography showed a large mid-body splenic mass. Contrast enhanced ultrasonography of the liver demonstrated a hypoechoic left lateral lobe nodular mass during the peak and late portal-phases of liver enhancement. Histopathology of the splenic mass and hepatic nodular mass confirmed haemangiosarcoma. The use of ultrasound microbubble contrast media in the diagnosis of hepatic metastasis in the cat has not been previously reported in the cat.
Primary mycoplasma pneumonia associated with reversible respiratory failure in a cat
Authors: Trow Amy V. , Rozanski Elizabeth A. , Tidwell Amy S.
Published: April 2008

A young adult cat was evaluated for respiratory failure. Diagnostic testing, including computed tomography and culture, documented a primary Mycoplasma species pneumonia. The cat was treated aggressively with supportive care, including mechanical ventilation and appropriate antibiotics including doxycycline, and made a complete recovery. This is a unique case in respect of the severity of the Mycoplasma species pneumonia as well as the cat's recovery from severe lung injury.
The Soviet origin of Russian chauvinism: Voices from below
Authors: Joo Hyung-min
Published: April 2008

The fledgling democracy of Russia is facing many challenges. Perhaps the most dangerous of all is the rise of an aggressive chauvinistic nationalism. Initially, political analysts regarded it as a “recent” phenomenon which was filling in the ideological vacuum left by communism. As time went on, however, scholars began to grasp its deep historical roots and investigate its ideological evolution during the Soviet period. In this process, they tended to focus on the “legitimate” domains of the Soviet system – such as the official press, the literary field of socialist realism, and so on – in order to investigate how “the Russian idea” overtly coexisted or even covertly prospered within the boundaries of officially sanctioned ideology. The main goal of this paper is to bring a new dimension to our understanding of contemporary Russian nationalism, by approaching the whole phenomenon from below. While focusing on the Soviet period, this paper traces the ideological evolution of Slavophiles and their selective degeneration into chauvinism at the social level. In particular, it analyzes the underground ideological field of samizdat – uncensored illicit publications – where Slavophiles played a significant role. In this way, we can hear the “unfiltered” voices of rising Russian nationalists during the Soviet era.
Beneficial or harmful influence of phytosterols on human cells?
Authors: Rubis Blazej , Paszel Anna , Kaczmarek Mariusz , Rudzinska Magdalena , Jelen Henryk , Rybczynska Maria
Published: April 2008

So far, a protective influence of phytosterols on the human organism and atherogenesis has been suggested. Most studies have concentrated on the cytotoxic efficacy of phytosterols on cancer cells. However, there are only a few reports showing their influence on normal cells. The aim of the present study was to determine whether dietary plant sterols and their thermal processing products could influence the viability of normal, abdominal endothelial cells that play a crucial role in atherogenesis. Thus, we studied the effect of rapeseed oil-extract components, β-sitosterol, cholesterol and their epoxy-derivatives, 5α,6α-epoxy-β-sitosterol and 5α,6α-epoxycholesterol, on the proliferation and viability of human abdominal aorta endothelial cells HAAE-2in vitro. We showed strong cytotoxic properties of β-sitosterol in HAAE-2 cells (half maximal inhibitory concentration (IC50) = 1·99 (sem0·56) μm) and, interestingly, a weaker cytotoxic effect of 5α,6α-epoxy-β-sitosterol (IC50>200 μm). Moreover, we observed a significantly stronger cytotoxic activity of β-sitosterol than cholesterol (IC50 = 8·99 (sem2·74) μm). We also revealed that β-sitosterol as well as cholesterol caused apoptosis, inducing caspase-3 activity in the cells (60 % increase compared with control cells) that corresponded to the DNA fragmentation analysis in a terminal uridine deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labelling (TUNEL) study. Although absorption of plant sterols is low compared with cholesterol, they can still influence other physiological functions. Since they effectively reduce serum LDL-cholesterol and atherosclerotic risk but also decrease the viability of cancer cells as well as normal cells in a time- and dose-dependent mannerin vitro, their influence on other metabolic processes remains to be elucidated.
Interactions of ethanol drinking withn-3 fatty acids in rats: potential consequences for the cardiovascular system
Authors: Guiraud Annabelle , de Lorgeril Michel , Zeghichi Sabrina , Laporte François , Salen Patricia , Saks Valdur , Berraud Nathalie , Boucher François , de Leiris Joël
Published: April 2008

Moderate ethanol drinking (ED) andn-3 fatty acids have both been associated with low cardiac mortality. However, there are few data evaluating the interactions of ED withn-3. We recently reported that moderate ED results in increasedn-3 in cardiac patients. The main aim of the present study was, through a well-controlled experimental model, to confirm that chronic ED actually results in increasedn-3. Secondary aims were to examine the effects of chronic ED on cardiac mitochondria, cardiac function and experimental myocardial infarction. We studied the fatty acid profiles of plasma, cell membranes and cardiac mitochondria phospholipids in a rat model of chronic ED. In plasma and cell membranes, ED actually resulted in highern-3 (P = 0·005). In mitochondria phospholipids of ED rats,n-3 were also increased (P < 0·05) but quite modestly. Cardiac mitochondrial function and left ventricular function were not significantly different in ED and control rats, while infarct size after 30 min ischaemia and reperfusion was smaller (P < 0·0001) in ED rats. This is the first animal study confirming interaction of alcohol drinking withn-3. We found no harmful effect of chronic ED on the heart in that model but a significant cardioprotection. Further studies are warranted to investigate the mechanisms by which moderate ED alters the metabolism ofn-3 and whethern-3 are the mediators of the ED-induced cardioprotection.
Hypolipidaemic effects of fenofibrate and fasting in the herbivorous grass carp (Ctenopharyngodon idella) fed a high-fat diet
Authors: Du Zhen-Yu , Clouet Pierre , Degrace Pascal , Zheng Wen-Hui , Frøyland Livar , Tian Li-Xia , Liu Yong-Jian
Published: April 2008

We investigated whether the hypolipidaemic effect of fenofibrate and fasting observed in most omnivorous mammals may also apply to herbivorous fish. Grass carp (Ctenopharyngodon idella) fed a high-fat (8 %) diet exhibited a marked increase in blood lipids and body fat after 6 weeks. They were then treated with fenofibrate (100 mg/kg body weight) in the same high-fat diet for 2 weeks, followed by fasting for 1 week. Plasma lipid concentration, body fat amount, fatty acid composition, plasma thiobarbituric acid-reactive substances and some parameters related to hepatic fatty acid oxidation were measured, and liver samples were stained for histological examination. Fenofibrate treatment decreased TAG and cholesterol concentrations in plasma, total lipids of the whole body and liver, and EPA and DHA contents in tissues. Further, a mobilisation of mesenteric fat concomitant with an increase in hepatic peroxisomal fatty acid oxidation and lipid peroxidation was observed. Compared with fenofibrate treatment, fasting decreased body weight and plasma TAG, but not plasma cholesterol. It also reduced the fat content of the whole body and increased the EPA and DHA contents in the liver and other tissues. Fatty acid oxidation was stimulated by fasting in mitochondria, but not in peroxisomes. These data suggest that fenofibrate and fasting regulate the lipid metabolism in grass carp through different metabolic pathways. The grass carp is moderately responsive to a fibrate derivative in comparison with the well-known excess responsiveness of the rat model, and so it could be used for the study of lipid abnormalities as a herbivorous model.
Tagging Icelandic text: A linguistic rule-based approach
Authors: Loftsson Hrafn
Published: April 2008

The Icelandic language is a morphologically complex language, for which a large tagset has been created. This paper describes the design of a linguistic rule-based system for part-of-speech tagging Icelandic text. The system contains two main components: a disambiguator, IceTagger, and an unknown word guesser, IceMorphy. IceTagger uses a small number of local elimination rules along with a global heuristics component. The heuristics guess the functional roles of the words in a sentence, mark prepositional phrases, and use the acquired knowledge to force feature agreement where appropriate. IceMorphy is used for guessing the tag profile for unknown words and for automatically filling tag profile gaps in the lexicon. Evaluation shows that IceTagger achieves 91.54% accuracy, a substantial improvement on the highest accuracy, 90.44%, obtained using three state-of-the-art data-driven taggers. Furthermore, the accuracy increases to 92.95% by using IceTagger along with two data-driven taggers in a simple voting scheme. The development time of the tagging system was only seven man-months, which can be considered a short development period for a linguistic rule-based system.
Acceptability and processing of long-distance dependencies in Danish
Authors: Poulsen Mads
Published: April 2008

Long-distance dependencies have been the object of much theoretical interest in the Scandinavian languages and in general, but the empirical foundation for theorizing has been limited. The present paper investigates extraction from complement and adverbial clauses in Danish using acceptability judgment and reading-time measures. Extraction from adverbial clauses was found to be rated near the bottom of the scale and to be associated with a processing cost. This was also true of extraction in adverbial clauses in semantically cohesive sentences, which Jensen (2001a, b) has suggested is acceptable. It is concluded that under the conditions investigated extraction from adverbial clauses in Danish is associated with a processing cost and very low acceptability ratings, despite semantic cohesion.
Note from the Editors
Authors: Ringen Catherine , Vikner Sten
Published: April 2008

This is the first issue of volume 31 of the Nordic Journal of Linguistics. The NJL is the journal of the Nordic Association of Linguists. Individuals may subscribe to the Nordic Journal of Linguistics by joining the Nordic Association of Linguists. The NAL membership form can be found on the Cambridge University Press web site of the NJL, , as well as on the NAL web site, . We are well aware that there have been problems with joining the NAL in the not so distant past, but we have reasons to hope that soon such problems will only be a memory.
Greedy approximation
Authors: Temlyakov V. N.
Published: April 2008

In this survey we discuss properties of specific methods of approximation that belong to a family of greedy approximation methods (greedy algorithms). It is now well understood that we need to study nonlinear sparse representations in order to significantly increase our ability to process (compress, denoise,etc.) large data sets. Sparse representations of a function are not only a powerful analytic tool but they are utilized in many application areas such as image/signal processing and numerical computation. The key to finding sparse representations is the concept ofm-term approximation of the target function by the elements of a given system of functions (dictionary). The fundamental question is how to construct good methods (algorithms) of approximation. Recent results have established that greedy-type algorithms are suitable methods of nonlinear approximation in bothm-term approximation with regard to bases, andm-term approximation with regard to redundant systems. It turns out that there is one fundamental principle that allows us to build good algorithms, both for arbitrary redundant systems and for very simple well-structured bases, such as the Haar basis. This principle is the use of a greedy step in searching for a new element to be added to a givenm-term approximant.
Wound healing and local neuroendocrine regulation in the injured liver
Authors: Ebrahimkhani Mohammad R. , Elsharkawy Ahmed M. , Mann Derek A.
Published: April 2008

The hepatic wound-healing response is a complex process involving many different cell types and factors. It leads to the formation of excessive matrix and a fibrotic scar, which ultimately disrupts proper functioning of the liver and establishes cirrhosis. Activated hepatic myofibroblasts, which are derived from cells such as hepatic stellate cells (HSCs), play a key role in this process. Upon chronic liver injury, there is an upregulation in the local neuroendocrine system and it has recently been demonstrated that activated HSCs express specific receptors and respond to different components of this system. Neuroendocrine factors and their receptors participate in a complex network that modulates liver inflammation and wound healing, and controls the development and progression of liver fibrosis. The first part of this review provides an overview of the molecular mechanisms governing hepatic wound healing. In the second section, we explore important components of the hepatic neuroendocrine system and their recently highlighted roles in HSC biology and hepatic fibrogenesis. We discuss the therapeutic interventions that are being developed for use in antifibrotic therapy.
Composition of the crust beneath southeastern China derived from an integrated geophysical data set
Authors: Zhang Zhongjie , Zhang Xi , Badal José
Published: April 2008

The nonuniqueness in determining the composition of the crust can be reduced by comparing the data for P‐wave velocity (Vp), S‐wave velocity (Vs), Vp/Vs ratio, mass density (ρ) and Lamé impedances (ρλ, ρμ) to data determined from laboratory measurements of these physical variables on a variety of crustal rock samples. The composition of the crust along the Tunxi‐Wenzhou transect, southeastern China, is presented as a model based on a complete set of geophysical data involving seismic P‐wave and S‐wave velocity, density, gravity, heat flow, and temperature surveys, which allow us to place tighter constraints on possible crustal models. The Yangtze and the Cathaysia blocks have a crustal structure characterized by remarkable differences between the upper, middle, and lower crust. Integrated geophysics data are here interpreted to indicate: (1) an average composition of granite gneiss for the upper crust, with presence of mica quartz schist, felsic granulite, paragranulite, and granite‐granodiorite beneath the Yangtze block, and basalt down to the upper part of the middle crust just over the Jiangshan‐Shaoxing fault, followed laterally by granite gneiss beneath the Songyang, Qintiang, and Wenping depressions; (2) granite‐granodiorite and biotite gneiss for the upper half of the middle crust, with presence of mica quartz schist beneath the Cathaysia block; (3) gabbro and in less proportion basalt for the lower part of the middle crust; and (4) amphibolite for the lower crust, with presence of mafic garnet granulite just over the Jiangshan‐Shaoxing fault and beneath the Wenping depression.
Determination of rapid Deccan eruptions across the Cretaceous‐Tertiary boundary using paleomagnetic secular variation: Results from a 1200‐m‐thick section in the Mahabaleshwar escarpment
Authors: Chenet Anne‐Lise , Fluteau Frédéric , Courtillot Vincent , Gérard Martine , Subbarao K. V.
Published: April 2008

Flow‐by‐flow reanalysis of paleomagnetic directions in two sections of the Mahabaleshwar escarpment, coupled with analysis of intertrappean alteration levels shows that volcanism spanned a much shorter time than previously realized. The sections comprise the upper part of magnetic chron C29r, transitional directions and the lowermost part of C29n. Lack of paleosecular variation allows identification of four directional groups, implying very large (40 to 180 m thick) single eruptive events (SEEs) having occurred in a few decades. Paleomagnetism allows temporal constraints upon the formation of 9 out of 23 thin red bole levels found in the sections to no more than a few decades; the two thickest altered layers could have formed in 1 to 50 ka. The typical volumes of SEEs (corresponding to magnetic directional groups) are estimated at 3000 to 20,000 km3, with flux rates ∼100 km3a−1, having lasted for decades. Flood basalt emission can be translated into SO2injection rates of several Gt a−1, which could have been the main agent of environmental change. The total volume of SO2emitted by the larger SEEs could be on the order of that released by the Chicxulub impact. Moreover, each SEE may have injected 10 to 100 times more SO2in the atmosphere than the deleterious 1783 Laki eruption. The detailed time sequence of SEEs appears to be the key feature having controlled the extent of climate change. If several SEEs erupted in a short sequence (compared to the equilibration time of the ocean), they could have generated a runaway effect leading to mass extinction.