bluuebunny/crossref_metadata_2025 huggingface dataset:
DEGRADATION OF TOCOPHEROLS DURING NEAR‐AMBIENT RAPESEED DRYING
Authors: GAWRYSIAK‐WITULSKA MARZENA , SIGER ALEKSANDER , NOGALA‐KALUCKA MALGORZATA
Published: November 2009

Increased interest manifested by consumers in products rich in biologically active components makes it necessary to minimize their loss during drying and storage of raw materials for food production. In this study, the effect of drying conditions and further storage of rapeseed on changes in contents of tocopherols (T) and plastochromanol‐8 (PC‐8) was examined. Seeds of rape cv. Californium, Elektra and Livius, dried after harvest using the near‐ambient drying method in a bed of 2‐m thickness and air heated to a temperature of 60, 80 and 100C, were used. Contents of T and PC‐8 were determined immediately after drying and after 6 and 12 months of storage at 10 ± 2C. Quality and quantity of antioxidants in seeds were determined using high‐performance liquid chromatography. The near‐ambient seed drying method resulted in a decrease in T content by 6–11%, while that for hot air drying was 4–8%. Seed storage reduced the level of T by a further 23–30%. Similar dependences were found for PC‐8. The analyzed results demonstrated the effect of varietal differences, drying conditions and storage time on the contents of T and PC‐8 in rapeseed.

PRACTICAL APLICATIONS

Drying of rapeseed is one of the most energy‐intensive stages of its production. At the same time, one needs to consider that these seeds, as biological material, are highly sensitive to thermal treatment. Thus, search for best drying conditions with special emphasis on the preservation of bioactive components that affect human health is necessary. The analyses carried out compared the range of loss of natural antioxidants, tocochromanols, during drying and further storage of rapeseed dried using an energy‐saving near‐ambient drying and dried using hot air.
BIOACTIVE COMPOUNDS, VOLATILES AND ANTIOXIDANT ACTIVITY OF VIRGIN SEJE OILS (JESSENIA BATAUA) FROM THE AMAZONAS
Authors: NAVAS HERNÁNDEZ PETRA BEATRIZ , FREGAPANE GIUSEPPE , MOYA MARIA DESAMPARADOS SALVADOR
Published: November 2009

The aboriginal people of Amazon region cultivate the seje palm (Jessenia bataua) as a source of food and vegetable fiber. The oil, which is locally used mainly for medicinal purposes, is obtained from the palm fruits by artisanal procedures in which the fruit is heated in hot water and then the mass is pressed using a “sebucan.” The chemical characteristics of virgin seje oils obtained from eight Piaroa communities of the state of Amazonas, Venezuela, were evaluated, with particular emphasis on their minor constituents. The fatty acid profile indicated that oleic acid was the major component (>75%). The most abundant sterols were Δ5avenosterol andβ‐sitosterol, with relative contents of 35 and 38%, respectively. The most abundant aliphatic alcohols were those with 7, 8 and 10 carbon atoms. Among tocopherols, α‐tocopherol was predominant. Aldehydes such as heptanal, octanal and decanal were present in the volatile fraction along with terpenoid compounds.

PRACTICAL APLICATIONS

The virgin seje oil is an important source of edible oil with high oleic acid content and low concentrations of saturated fatty acids, which is different from oils other than palm oils. It can be used as edible oil and also for soap making, in cosmetics and for medical treatment of pulmonary diseases such as bronchitis and tuberculosis. It is also an important source of a nonconventional vegetable oil with bioactive compounds of special interest from a nutritional point of view. In general, this oil has a great potential due to the increasing use of lower quality edible oils for the production of biodiesel.
Translating Tradition: The Poetics and Politics of Diasporic Media
Authors: Harindranath R.
Published: November 2009

This essay argues that the recent academic interest in diaspora, the media and the research that it has engendered have provided unique insights into the media’s role in the creation and maintenance of an alternative public sphere. Despite this however, the difficulties in defining ‘diaspora’ as a concept, and the attempts, by both academics and diasporic cultural elites, to propose a degree of homogeneity within diaspora communities undermines the politics that is inherent in diasporic media representation and consumption. The essay makes a plea for conceptual clarity and the recognition of power within the diaspora communities, both of which are crucial for future research in the media and diasporas.
Rethinking Families Over the Life Course Development Perspective: Including the Lives of Same‐Sex Families
Authors: Easterbrook Adam
Published: November 2009

This paper has three objectives. The first goal is to summarize the literature on same‐sex families relating to the major life transitions of relationship formation, marriage, parenting, relationship dissolution, and old age. For the most part, this literature remains scant, with many areas completely ignored. Second, reasons why there is relatively little known about the life course of same‐sex families will be examined. In particular, we argue that the life course’s focus on marriage as a marker for transitions, including whether or not transitions are on or off time, works to exclude same‐sex families since they are not legally able to marry in most countries. The third objective is to explore if, and how, the family life course development perspective can be adapted or modified so that it can account for the diversity of both same and opposite‐sex families.
Providing Interdisciplinary Services to At‐Risk Families to Prevent the Placement of Children In Foster Care
Authors: Weimer Deborah J.
Published: November 2009

Grandparents need support to take on the responsibility of children whose parents cannot care for them due to drug addiction, mental health issues, HIV illness, or other health problems. Without support and assistance, these families and children are likely to end up enmeshed in the already overburdened child abuse and neglect system. The University of Maryland has created a model program providing social work and legal services to at‐risk grandparent families to help avoid the unnecessary placement of these children in foster care. In this new program, student attorneys and student social workers worked with the grandparent client to help stabilize the family, providing representation or advice on housing, public benefits, custody, and school‐related issues. Joint education of student attorneys and student social workers in a clinical experience enhances their understanding of their roles and those of the other profession and prepares them for a more thoughtful and informed approach to family law, child welfare cases, and at‐risk children.
Crystal Structure of the Catalytic Core of an RNA-Polymerase Ribozyme
Authors: Shechner David M. , Grant Robert A. , Bagby Sarah C. , Koldobskaya Yelena , Piccirilli Joseph A. , Bartel David P.
Published: November 2009

Revealing the RNA World?

The RNA World hypothesis posits that at an early step in the appearance of life, RNA acted both as an information storage molecule and as an enzyme—or ribozyme. Such dual functionality would allow for an RNA species that could replicate itself and thus seed the beginning of molecular evolution. The involvement of RNA in a number of fundamental cell biological processes, together with its ability, either naturally or through in vitro evolution, to catalyze a range of chemical reactions, provides some indirect support for this view.

Shechner
et al.

(p.
1271
) have now determined the structure of an in vitro–evolved RNA ligase ribozyme that catalyses a chemical reaction essentially identical to that of proteins that replicate RNA. The active site of the RNA ligase could be superimposed upon that of the protein enzyme to reveal analogous residues important for the catalytic joining of RNA moieties. These findings will help in the engineering of more effective ribozyme polymerases.
The Extracellular Matrix: Not Just Pretty Fibrils
Authors: Hynes Richard O.
Published: November 2009

The extracellular matrix (ECM) and ECM proteins are important in phenomena as diverse as developmental patterning, stem cell niches, cancer, and genetic diseases. The ECM has many effects beyond providing structural support. ECM proteins typically include multiple, independently folded domains whose sequences and arrangement are highly conserved. Some of these domains bind adhesion receptors such as integrins that mediate cell-matrix adhesion and also transduce signals into cells. However, ECM proteins also bind soluble growth factors and regulate their distribution, activation, and presentation to cells. As organized, solid-phase ligands, ECM proteins can integrate complex, multivalent signals to cells in a spatially patterned and regulated fashion. These properties need to be incorporated into considerations of the functions of the ECM.
Educating Scientists About Dual Use
Authors: Sta. Ana Jennifer L. , Frankel Mark S. , Berger Kavita M.
Published: November 2009

Harmful misuse of biological research must be addressed through education, but such programs are in short supply and can be improved.
Subcellular mRNA Localization in Animal Cells and Why It Matters
Authors: Holt Christine E. , Bullock Simon L.
Published: November 2009

Subcellular localization of messenger RNAs (mRNAs) can give precise control over where protein products are synthesized and operate. However, just 10 years ago many in the broader cell biology community would have considered this a specialized mechanism restricted to a very small fraction of transcripts. Since then, it has become clear that subcellular targeting of mRNAs is prevalent, and there is mounting evidence for central roles for this process in many cellular events. Here, we review current knowledge of the mechanisms and functions of mRNA localization in animal cells.
Global Signatures and Dynamical Origins of the Little Ice Age and Medieval Climate Anomaly
Authors: Mann Michael E. , Zhang Zhihua , Rutherford Scott , Bradley Raymond S. , Hughes Malcolm K. , Shindell Drew , Ammann Caspar , Faluvegi Greg , Ni Fenbiao
Published: November 2009

Patterns of Change

The global climate record of the past 1500 years shows two long intervals of anomalous temperatures before the obvious anthropogenic warming of the 20th century: the warm Medieval Climate Anomaly between roughly 950 and 1250 A.D. and the Little Ice Age between around 1400 and 1700 A.D. It has become increasingly clear in recent years, however, that climate changes inevitably involve a complex pattern of regional changes, whose inhomogeneities contain valuable insights into the mechanisms that cause them.

Mann
et al.

(p.
1256
) analyzed proxy records of climate since 500 A.D. and compared their global patterns with model reconstructions. The results identify the large-scale processes—like El Niño and the North Atlantic Oscillation—that can account for the observations and suggest that dynamic responses to variable radiative forcing were their primary causes.
Crystal Structure of a Nucleocapsid-Like Nucleoprotein-RNA Complex of Respiratory Syncytial Virus
Authors: Tawar Rajiv G. , Duquerroy Stéphane , Vonrhein Clemens , Varela Paloma F. , Damier-Piolle Laurence , Castagné Nathalie , MacLellan Kirsty , Bedouelle Hugues , Bricogne Gérard , Bhella David , Eléouët Jean-François , Rey Félix A.
Published: November 2009

RSV in 3D

Respiratory syncytial virus (RSV) causes pneumonia and bronchiolitis in infants. RSV is an RNA virus in which the genomic RNA forms part of a nuclease-resistant helical ribonucleoprotein complex.

Tawar
et al.

(p.
1279
) now use x-ray and electron microscopy data to model the structure of this nucleocapsid complex and show how it can template RNA synthesis. The crystal structure shows RNA wrapped around a decameric ring of nucleocapsid protein. Combining this structure with electron microscopy data gives a model that shows how polymerase might read out the RNA bases without disassembling the nucleocapsid helix.
Formation of Compositionally Abrupt Axial Heterojunctions in Silicon-Germanium Nanowires
Authors: Wen C.-Y. , Reuter M. C. , Bruley J. , Tersoff J. , Kodambaka S. , Stach E. A. , Ross F. M.
Published: November 2009

Sharp Nanowires

The potential for using nanowires in devices can be limited by the ability to synthesize them from two or more materials while maintaining compositional purity at the interfaces. Instead of using liquid droplets at the eutectic point when the melting point is at a minimum,

Wen
et al.

(p.
1247
) show that generating the wires at solid alloy catalysts allows fabrication of silicon germanium wires with atomically sharp interfaces. The system works well because an AlAu alloy composition was chosen in which Si and Ge have a low solubility but which have a high enough eutectic temperature so that nanowire growth is not limited by the reactivity of the Si and Ge precursors.
Haploid Genetic Screens in Human Cells Identify Host Factors Used by Pathogens
Authors: Carette Jan E. , Guimaraes Carla P. , Varadarajan Malini , Park Annie S. , Wuethrich Irene , Godarova Alzbeta , Kotecki Maciej , Cochran Brent H. , Spooner Eric , Ploegh Hidde L. , Brummelkamp Thijn R.
Published: November 2009

“Haploid Human”

Genetic screens can provide direct insight into biological processes that are poorly understood.

Carette
et al.

(p.
1231
) describe genetic screens using large-scale gene disruption in human cells haploid for all chromosomes except for chromosome 8. One screen was used to identify host factors essential for the activity of cytolethal distending toxin, a toxin found in several pathogenic bacteria. Another screen identified host gene products essential for infection with influenza, and an additional screen revealed genes required for the action of adenosine 5′-diphosphate (ADP)–ribosylating bacterial toxins. This loss-of-function genetic approach in mammalian cells will be widely applicable to study a variety of biological processes and cellular functions.
Directed Transport of Atoms in a Hamiltonian Quantum Ratchet
Authors: Salger Tobias , Kling Sebastian , Hecking Tim , Geckeler Carsten , Morales-Molina Luis , Weitz Martin
Published: November 2009

Moving Cold Atoms with Quantum Ratchets

The nanoscale dimensions of biological motors make them susceptible to thermal noise, but such motors can produce force in one direction by alternating application of an asymmetric potential, or ratchet, with periods of thermal drift in the motion. The quantum version of such motors can operate without dissipation, as long as there is some means to break time-reversal symmetry in the system.

Salger
et al.

(p.
1241
) report on a coherent quantum ratchet device consisting of Bose-Einstein condensate cold atoms placed into an asymmetric sawtooth-potential created by optical lattices. Symmetry breaking was accomplished by phase shifts in the driving potentials. As expected for such a quantum ratchet, the current depended on the initial phase of the driving potential.
Variety—the Splice of Life—in Microbial Communities
Authors: Banfield Jillian F. , Young Mark
Published: November 2009

Splicing of viral fragments into bacterial and archaeal genomes may provide protection against viral predation.
On the Origin of Species by Natural and Sexual Selection
Authors: van Doorn G. Sander , Edelaar Pim , Weissing Franz J.
Published: November 2009

Local Selection of Magic Traits

Ecological interactions can favor specialization, and sexual selection can induce reproductive isolation; however, these processes are insufficient by themselves to create new species. They must act in concert and on the same set of genes.

Van Doorn
et al.

(p.
1704
, published online 26 November; see the Perspective by

Mank

) present a theoretical model that shows that within a larger population the evolution of mating preferences will favor sexual ornaments that indicate the degree of adaptation to the local ecological conditions, for example, the abundant song of a male bird that can obtain food easily because it has the right bill size for the seeds in that locale. Once mate choice evolves on the basis of a signal of local adaptation, natural and sexual selection will mutually enforce each other, ultimately leading to speciation.
Ligand-Enabled Reactivity and Selectivity in a Synthetically Versatile Aryl C–H Olefination
Authors: Wang Dong-Hui , Engle Keary M. , Shi Bing-Feng , Yu Jin-Quan
Published: November 2009

Heck of an Alternative

The Mizoroki-Heck reaction is widely used in organic synthesis to link together unsaturated carbon fragments such as olefins and arenes. However, one of its drawbacks is the need to append a reactive group such as a halogen to one of the reagents beforehand.

Wang
et al.

(p.
315
, published online 26 November) present an alternative palladium-catalyzed reaction that links olefins directly to aryl acids. Oxygen added to the reaction medium concurrently oxidizes the aryl C-H bond at the linkage site, eliminating the need for prior halogenation. Introducing amino acid–derived ligands tunes the aryl site at which the reaction takes place, and efficient reactivity can be achieved across a diverse range of substrates.
Nuclear Export of Small RNAs
Authors: Stewart Murray
Published: November 2009

The machinery that exports small RNAs from the cell nucleus is fine-tuned to recognize when the processing of each class of RNA has been completed.
On Incentives for Innovation
Authors: Alberts Bruce
Published: November 2009

For science to thrive, it is crucial that the scientific community encourage the bold ambitions and innovative spirit of young researchers. In my own area of science, the United States could do much more to support this important goal. U.S. biomedical science is a large and important research enterprise that currently includes over 100,000 graduate students and postdoctoral fellows. Of these, only a select few will go on to become independent research scientists in academia. Assuming that the system supporting this career path works well, these will be the individuals with the most talent and interest in such an endeavor: young people well positioned to make the scientific breakthroughs that societies need to survive and thrive. But the current system squanders the creativity and energy of these exceptionally gifted young people through a funding process that forces them to avoid risk-taking and innovation.
Farm Fungicides Linked to Resistance in a Human Pathogen
Authors: Enserink Martin
Published: November 2009

A team of Dutch researchers claims that the massive use of fungicides to protect European orchards, vineyards, and grain fields may be contributing to resistance against drugs used to treat people with life-threatening infections of
Aspergillus fumigatus
.
Science and the Stimulus
Authors: Mervis Jeffrey
Published: November 2009

An $18 billion burst of funding from the $787 billion American Recovery and Reinvestment Act is nurturing U.S. research. Where did it go, and is it being spent wisely?
Unlocking the Secrets of microRNA
Authors: Harding Anne
Published: November 2009

Microarrays are a vital tool in research on microRNAs, the tiny noncoding stretches of genetic material that regulate messenger RNA. They can't be beat for reading the microRNA "fingerprints" unique to disease states. But keeping up with this super hot field is a challenge for commercial microarray makers, and competition is fierce.
The Relevance of Childhood Developmental Factors to the Efficacy of Acupuncture on the Affective Component of Back Pain
Authors: Straiton Nicholas
Published: November 2009

There is substantial evidence to support the use of acupuncture in the treatment of low back pain. The main predictors of chronic low back pain are non-medical and psychosocial. The understanding of how acupuncture can modulate the pain experience has recently been enhanced by the elucidation of the role of C fibre afferents on the limbic system. C fibre deactivation of the limbic system can only occur in the presence of intact corticosubcortical neuronal pathways. The normal development of these pathways is determined by social factors in the early years of life. The effect of acupuncture treatment for low back pain may be determined by successful relationships between the mother and child in the first 18 months of life.
Increased H-Reflex Response Induced by Intramuscular Electrical Stimulation of Latent Myofascial Trigger Points
Authors: Ge Hong-You , Serrao Mariano , Andersen Ole K , Graven-Nielsen Thomas , Arendt-Nielsen Lars
Published: November 2009

Background

Myofascial trigger points (MTrPs) present with mechanical hyperalgesia and allodynia. No electrophysiological evidence exists as to the excitability of muscle spindle afferents at myofascial trigger points MTrPs. The purpose of this current study was to explore whether an H-reflex response could be elicited from intramuscular electrical stimulation. If so, to assess the possibility of increased reflex response at MTrPs.

Methods

The H-reflex latency and the conduction velocity were first determined from electrical stimulation of the tibial nerve in 13 healthy subjects. Then an intramuscular monopolar needle electrode was inserted randomly into a latent MTrP or a non-MTrP in the gastrocnemius muscle. Electrical stimuli at different intensities were delivered via the intramuscular recording electrode to the MTrP or non-MTrP.

Results

The average conduction velocity (44.3 ± 1.5 m/s) of the electrical stimulation of tibial nerve was similar (p>0.05) with the conduction velocity (43.9 ± 1.4 m/s) of intramuscular electrical stimulation. The intramuscular H-reflex at MTrPs was higher in amplitude than non-MTrPs (p<0.001). The reflex threshold was lower for MTrPs than non-MTrPs (p<0.001).

Conclusion

The current study provides first electrophysiological evidence that intramuscular electrical stimulation can evoke H-reflex, and that higher H-reflex amplitude and lower H-reflex threshold exist at MTrPs than non-MTrPs respectively, suggesting that muscle spindle afferents may be involved in the pathophysiology of MTrPs.
A Review of the Potential Effect of Electroacupuncture and Moxibustion on Cell Repair and Survival: The Role of Heat Shock Proteins
Authors: Cakmak Yusuf Ozgur
Published: November 2009

In recent years, a considerable amount of research has been focused on the underlying mechanisms of electroacupuncture and moxibustion assisted tissue repair. Intracellular protein denaturation is a significant pathological step of acute conditions such as stroke, myocardial infarction and acute pancreatitis. Protein aggregation can be observed after the protein denaturation step in chronic diseases of the central nervous system like Alzheimer's and Parkinson's disease, and also in other chronic system diseases including cataract formation. Heat shock proteins (HSPs) are fundamental for intracellular protein repair and work by preventing protein aggregation and assisting denaturated proteins to refold. Further, HSPs can also function for extracellular cell signalling. The focus of this review is to analyse the data studying electroacupuncture and moxibustion induced HSPs, and how acupuncture can survive cells from apoptosis under stress.
Integration of Acupuncture for Outpatients and Inpatients in a General Hospital in Brazil
Authors: Saad Marcelo , Jorge Liliana Lourenço , Vieira Mario Sergio Rossi , de Medeiros Roberta
Published: November 2009

Acupuncture and related techniques have increasingly been offered in conventional medical settings in Western societies. In Hospital Israelita Albert Einstein, Brazil, acupuncture has been integrated into the care pathways since October 2005. Since then, medical acupuncture has been offered for both inpatients and outpatients. Acupuncture has become an integrated therapeutic modality both for outpatients in the clinic setting and for inpatients in the wards. It has been observed that acupuncture performed in a hospital differs in specific characteristics when compared with acupuncture performed in an outpatient setting. The main differences found between inpatients and outpatients treatment are summarised and attitudes and cautionary measures to be taken into account during application of acupuncture in inpatients are suggested. Future plans for the service include offering acupuncture in the emergency ward and surgical centre. The description of this experience could encourage other hospitals to develop an acupuncture service.
The Michael Gabbro and other Mesoproterozoic lithospheric probes in southern and central Labrador
Authors: Emslie Ronald F. , Hamilton Michael A. , Gower Charles F.
Published: November 2009

The Michael Gabbro (1426 Ma) and the Shabogamo Gabbro (1459 Ma) represent two large diabase intrusive episodes that affected the northwestern margin of the northeastern Grenville Province. Both have sustained variable effects of subsequent Grenvillian metamorphism. Other broadly contemporaneous magmatic activity in the region includes the formation of Elsonian anorthosite–granitoid complexes (1.46–1.29 Ga) that intruded Churchill Province and Nain Province rocks to the north, the Harp dykes (1.27 Ga), and Mealy dykes (~1.25 Ga). Petrologic and geochemical data show that the Michael Gabbro and Shabogamo Gabbro are similar, with the latter displaying more cumulate rock characteristics, and the former having compositions closer to those of rapidly cooled magma. Both have compositions comparable to those of other continental diabases and to some continental flood basalts. Sr and Nd initial isotopic compositions of Michael Gabbro (εNd(1426 Ma) = −4.7 to −6.0, ISr(1426 Ma) = 0.7032–0.7044) and Shabogamo Gabbro (εNd(1459 Ma) = −4.0 to −5.5, ISr(1459 Ma) = 0.7020–0.7060) are alike and overlap, suggesting similar sources and processes of development. Comparisons with other nearly contemporary mafic suites in central and southern Labrador show that only the Mealy dykes have a distinctly more radiogenic isotopic signature. Paradoxically, other mafic suites that intrude older basement rocks north of the Grenville Front have less enriched Nd signatures than do those that intrude younger basement rocks south of the front. The argument is made that the subcontinental lithospheric mantle, and not crustal contamination, played the most influential role in evolution of the magmas.
Provenance of Paleozoic sedimentary rocks in the Canadian Cordilleran miogeocline: a Nd isotopic study
Authors: Garzione Carmala N. , Patchett P. Jonathan , Ross Gerald M. , Nelson JoAnne
Published: November 2009

Nd isotopes and trace elements in sedimentary rocks of the Yukon, the Northwest Territories, and northern British Columbia are used to examine the source of sediments in the Canadian Cordilleran miogeocline. Previous Nd isotope studies in southern Alberta demonstrated that strata of Neoproterozoic to Late Ordovician age were derived from Archean and Proterozoic Canadian Shield sources, whereas by the Late Devonian, a shift of 6 εNd units to younger crustal sources (εNd (T) = −6 to −9) had occurred. In this study, we found that the shift to younger crustal Nd isotopic signatures in the Yukon and Northwest Territories occurred much earlier than in southern Alberta. Cambrian and older strata have εNd(T) values of −10.0 to −21.1, consistent with derivation from Canadian Shield sources. Lower Ordovician through Permian strata in the Yukon and Northwest Territories, including the Innuitian-derived Imperial Assemblage, have εNd(T) values of −5 to −11.4. In northern British Columbia, the shift to a younger source reflects a wider range of εNd(T) values, from -−8.7 to −14.6 in Middle Ordovician through Middle Devonian strata, suggesting continued input from Canadian Shield sources. By the Middle Devonian, a complete shift to younger crustal signatures (εNd(T) = −5.9 to −10.5) had occurred in northern British Columbia. Several sources for the more juvenile sediments include (1) a mixture of locally erupted volcanic rocks with Canadian Shield sources, (2) a Grenville source, and (3) an Innuitian source. We propose that Ordovician to Lower Devonian strata were derived from a mixture of locally erupted, juvenile volcanics and pre-Cambrian Canadian Shield sources, and post-Middle Devonian strata were sourced from the Innuitian orogen in the Canadian Arctic.
Occurrence and significance of Silurian K-bentonite beds at Arisaig, Nova Scotia, eastern Canada
Authors: Bergström Stig M. , Huff Warren D. , Kolata Dennis R. , Melchin Michael J.
Published: November 2009

The most extensive succession of K-bentonite beds known in the Silurian of North America occurs at Arisaig on the northern coast of Nova Scotia. At least 40 ash beds are present in the Llandoverian Ross Brook Formation and at least four in the early Ludlovian McAdam Brook Formation. Most of the beds are thin (< 5 cm), but one bed (the Smith Brook K-bentonite bed) in the late Llandoverian crenulata Zone and another (the McAdam Brook K-bentonite bed) in the early Ludlovian nilssoni Zone each reach a thickness of 20 cm. New graptolite collections provide critical information on the biostratigraphic position of the K-bentonite beds in the Ross Brook Formation. Geochemical data show that the Arisaig ash beds represent calc-alkaline magmas from plate margin, subduction-related volcanic vents. Differences in K-bentonite stratigraphic distribution, combined with paleogeographic considerations, suggest that the volcanoes were located much farther to the south in the Iapetus than the source volcanoes of the British–Baltoscandian Llandoverian K-bentonites.
Early to middle Cretaceous paleogeography of north-central British Columbia: stratigraphy and basin analysis of the Skeena Group
Authors: Bassett Kari N. , Kleinspehn Karen L.
Published: November 2009

The Lower–middle Cretaceous Skeena Group records the Early Cretaceous evolution of the southern margin of the Jura-Cretaceous Bowser basin in north-central British Columbia. We formalize Skeena Group nomenclature and present interpretations of three distinct paleogeographic and tectonic phases. During the first phase (Neocomian–Aptian), Skeena deposition was limited to a restricted tidal basin represented by Laventie Formation black-shale deposits, surrounded by coal-swamp deltas of the lower Bulkley Canyon Formation. The lower Skeena Group, correlated to the McEvoy Formation (Bowser Lake Group) in the northern basin, represents final filling of the Bowser foredeep produced by Jurassic accretion of the Intermontane Superterrane to North America. In the second phase (early Albian – Early Cenomanian), marine deposition transgressed eastward and southward accompanied by intrabasinal Rocky Ridge volcanism shedding volcanic detritus into the Kitsuns Creek Member of the Bulkley Canyon Formation. The Rocky Ridge Formation does not correlate northward to other Bowser basin fill but represents intrabasinal volcanism in a transtensional setting along the Omineca continental arc. During the final phase (early–middle Cenomanian), red-bed chert-pebble fluvial deposits of the Rocher Deboule Formation prograded westward, shifting the shoreline to tide-dominated deltas on the far western basin margin. The Rocher Deboule Formation correlates to the Devil's Claw Formation (Bowser Lake Group), the lower member of the Tango Creek Formation (Sustut Group), and, tentatively, to the lower conglomeratic Kasalka Group, all attributed to transpressional Omineca uplift and cannibalization of older Bowser basin fill. Thus the southern basin margin evolved from an Early Cretaceous flexural foredeep to a middle Cretaceous arc setting dominated by oblique convergence, first transtensional then transpressional.
A comparison of foundation compaction techniques
Authors: Solymar Zoltan V. , Reed David J.
Published: November 2009

Soil investigation programs established the presence of locally loose to medium dense noncohesive foundation materials at three major industrial project sites. It was neccessary to densify these materials to ensure that unacceptable differential settlements did not occur between separate foundations and to reduce the potential for liquefaction of the looser zones in the event of seismic disturbance. Horizontal ground accelerations of 0.05, 0.1, and 0.3 g were used in the respective seismic analyses for the three sites. Four different techniques for in-place compaction were employed to densify the loose to medium dense soils: vibro and impact compaction, compaction piling, and deep blasting.Site descriptions and soil parameters measured are presented. A short explanation of design considerations and production work procedures is followed by a detailed comparison of the improvements obtained, measured in terms of standard or static cone penetration resistance and true relative density. Problems encountered and phenomena observed during performance of the work are described, such as the time-dependent strength increase in disturbed sands. Key words: compaction piling, deep blasting, impact compaction, vibrocompaction, foundation, penetration tests.
Static cone tests and settlement of calcareous desert sands
Authors: Ismael Nabil F. , Jeragh Abdul Majeed
Published: November 2009

The results of a recent in situ testing program to establish standard penetration test – cone penetration test (SPT–CPT) correlation for the windblown calcareous desert sands of Kuwait are presented and analyzed. The program consisted of auger borings and static cone tests at five sites along a 35 km long corridor. The resulting correlation was employed for prediction of the allowable soil pressure of footings at seven sites in Kuwait where load tests were carried out on square concrete footings placed at a depth of 1 m below ground surface. A comparison of the measured to the predicted soil pressures using the Schmertmann method indicated very close agreement. The average ratio of measured to predicted soil pressure is 93% for the seven test sites. Recommendations are made for further testing to determine the long-term settlement components due to creep and cyclic loading. Key words: load tests, sands, footings, allowable pressure, settlement, field tests, borings, cone penetration tests.
Surficial failures of alluvial stream banks
Authors: Ullrich C. Robert , Hagerty D. Joseph , Holmberg Ronald W.
Published: November 2009

Erosion of alluvial stream banks is of scientific and economic significance. The principal focus of this investigation was stream bank erosion caused by piping of sand seams, which leads to collapse of overlying strata. Analyses were performed to determine which parameters of the riverbank system are most important in controlling the amount and rate at which piping occurs. Among the failure mechanisms studied were wedge failure of large masses and surficial shearing (slabbing failure) of bank faces. Analyses showed that the most important factors governing piping were permeability and capillary suction in sand seams, slope of sand seams, and water in tension cracks behind the bank face. Flood hydrograph parameters (height of rise and duration of event) were less important, though significant. Whereas unit weight, cohesion, angle of internal friction, and water in tension cracks influenced wedge failures, only unit weight and cohesion directly influenced slabbing failures; however, those parameters influencing piping indirectly also influenced slabbing failures. Results of the analyses agreed closely with field observations. Key words: alluvial stream bank, erosion, sand seam, slope stability, piping, tension cracks, slabbing.
Ice lensing in layered soils
Authors: Penner Edward
Published: November 2009

The ice lensing phenomenon in layered soils, a condition that simulates the process of ice growth in varved soils, has been studied experimentally. Under the limited conditions of layer thicknesses, soils used, freezing rates, and moisture conditions, ice lenses formed at the face of the fine-textured (clay) layer when it was encountered by the freezing plane. Only minor heaving occurred in the coarse-textured (silt) layer when its thickness was increased. Key words: frost action, ice lensing, frost heaving, varved soils, layered soils.
The maximum discharge of outburst floods caused by the breaching of man-made and natural dams
Authors: Evans Stephen G.
Published: November 2009

The sudden release of water impounded in natural and man-made reservoirs has been responsible for some major disasters in mountainous regions of the world. Recent natural damming events and failures of natural dams have illustrated the need to examine the nature and magnitude of outburst floods and the behaviour of debris dams in general. An empirical relationship between maximum discharge (Qmax) and volume of water released during the outburst event (Vmax) is established (Qmax = 0.72Vmax0.53) for man-made dams and the relationship is thought applicable to the breaching of natural debris dams (landslides and moraines). This relationship allows a first-order estimate to be made of Qmax in the vicinity of the breach for a given Vmax during the failure of a man-made dam or a natural debris dam. Key words: outburst floods, man-made dams, natural dams, landslide, dam failure.
Pull-out capacity of single batter piles in sand
Authors: Hanna A. M. , Afram A.
Published: November 2009

The pull-out capacity of single rigid vertical and batter piles in sand and subjected to axial loading has been investigated. Good agreement was found when test results on instrumented model piles were compared with theoretical estimates. The effect of pile inclination on the pull-out capacity has been explained by means of variable mobilized passive earth pressure on the pile's perimeter. A design method and charts are presented. Key words: pile foundation, pull-out capacity, vertical pile, batter pile, sand–soil mechanics.
Gene disruption and characterization of a class V chitin synthase in Botrytis cinerea
Authors: Cui Zhifeng , Ding Zhenke , Yang Xiao , Wang Kun , Zhu Tingheng
Published: November 2009

Cell-wall chitin biosynthesis in the phytopathogenic fungus Botrytis cinerea involves 7 classes of chitin synthases. In this study, we disrupted a gene encoding a chitin synthase with a myosin-like motor domain (BcchsV) through Agrobacterium tumefaciens mediated transformation. The resulting mutant was not significantly affected in either growth characteristics or pathogenicity on tomato leaves. Surprisingly, the BcchsV mutant exhibited a 31% (m/m) increase in its chitin content compared with the wild-type strain. In addition, the BcchsV mutant showed increased sensitivity to Calcofluor White and slightly enhanced tolerance to cell-wall disturbing substances and osmosis regulators, including SDS, sorbitol, and NaCl. These results suggest that Bcchs does not play an essential role in the synthesis of cell-wall chitin in B. cinerea. However, disruption of this gene provoked a compensatory mechanism regulating the cellular response to cell-wall damage.
Pelagic fish hydrolysates as peptones for bacterial culture media
Authors: Beaulieu Lucie , Desbiens Michel , Thibodeau Jacinthe , Thibault Sharon
Published: November 2009

For several years in the Quebec fisheries’ industry,landings of pelagic fish have been calculated at over 4000 tons. These under-exploited species, rich in lipids and proteins, could be used in valuable new products. In the present study, hydrolysates of mackerel and herring were produced and utilized as sources of peptones in the formulation of new bacterial culture media. The molecular weight distribution analysis showed that molecules present in the hydrolysates were lower than 1300 Da for herring, and lower than 930 Da for mackerel. The formulated media were compared with reference media using 6 bacterial strains (3 lactic acid (LAB) and 3 non-lactic). The absorbance (OD) and carbohydrate measurements revealed that the formulated media possessed similar yields in comparison with the reference media. Finally, the inhibition of Listeria innocua by LAB bacteriocins was evaluated. Results obtained for Pediococcus acidilactici demonstrated high activities for each medium studied. Thus, the medium containing herring peptones generated the highest bacteriocin titre (32768 AU/mL), followed by both the medium containing mackerel peptones and the MRS7 medium (16384 AU/mL). Each medium containing the fish hydrolysates efficiently supported the growth of the bacterial strains. Pelagic fish peptones are promising as a novel bacterial culture media.
Ultrastructural and molecular characterization of endosymbionts of the reed beetle genusMacroplea(Chrysomelidae, Donaciinae), and proposal of “CandidatusMacropleicola appendiculatae” and “CandidatusMacropleicola muticae”
Authors: Kölsch Gregor , Matz-Grund Corinna , Pedersen Bo V.
Published: November 2009

Intracellular bacterial symbionts are known from various insect groups, particularly from those feeding on unbalanced diets, where the bacteria provide essential nutrients to the host. In the case of reed beetles (Coleoptera: Chrysomelidae, Donaciinae), however, the endosymbionts appear to be associated with specialized “glands” that secrete a material used for the beetles’ unusual water-tight cocoon. These glands were discovered over a century ago, but the bacteria they contain have yet to be characterized and placed in a phylogenetic context. Here, we describe the ultrastructure of two endosymbiotic species (“ Candidatus Macropleicola appendiculatae” and “ Candidatus Macropleicola muticae”) that reside in cells of the Malpighian tubules of the reed beetle species Macroplea appendiculata and Macroplea mutica , respectively. Fluorescent in situ hybridization using oligonucleotides targeting the 16S rRNA gene specific to Macroplea symbionts verified the localization of the symbionts in these organs. Phylogenetic analysis of 16S rRNA placed “Candidatus Macropleicola” in a clade of typically endosymbiotic Enterobacteriaceae (γ-proteobacteria). Finally, we discuss the evidence available for the hypothesis that the beetle larvae use a secretion produced by the bacteria for the formation of an underwater cocoon.
Influence of RpoS, cAMP-receptor protein, and ppGpp on expression of theopgGHoperon and osmoregulated periplasmic glucan content ofSalmonella entericaserovar Typhimurium
Authors: Costa Cristina S. , Pizarro Ramón A. , Antón Dora N.
Published: November 2009

A transcriptional fusion (opgG1::MudJ) to the opgGH operon of Salmonella enterica serovar Typhimurium (S. Typhimurium) LT2, isolated by resistance to mecillinam, was used to study the influence of global regulators RpoS, ppGpp, and cAMP/cAMP-receptor protein (CRP) on expression of the opgGH operon and osmoregulated periplasmic glucan (OPG) content. Neither high growth medium osmolarity nor absence of ppGpp or CRP had important effects on opgG1::MudJ expression in exponential cultures. However, under the same conditions, OPG content was strongly decreased by high osmolarity or cAMP/CRP defectiveness, and reduced to a half by lack of ppGpp. In stationary cultures, high osmolarity as well as CRP loss caused significant descents in opgG1::MudJ expression that were compensated by inactivation of RpoS σ factor. No effect of RpoS inactivation on OPG content was observed. It is concluded that opgGH expression in S. Typhimurium is only slightly affected by high osmolarity, but is inversely modulated by RpoS level. On the other hand, osmolarity and the cAMP/CRP global regulatory system appear to control OPG content, either directly or indirectly, mainly at the post-transcriptional level.
Effects of ergosterol on the structure and activity ofNeurosporamitochondrial porin in liposomes
Authors: Bay Denice C. , Court Deborah A.
Published: November 2009

Mitochondrial porins (also known as voltage-dependent anion-selective channels (VDACs)) regulate and contribute to cellular metabolism. These proteins copurify with sterols, and some purified forms of the protein require sterol for insertion into planar artificial membranes. Recently, interactions between detergent-solubilized mitochondrial porins and sterols have been detected by NMR and spectroscopic methods, but the effects of sterols on pore function remained to be assessed. Therefore, in this work, a freeze–thaw technique was used to introduce recombinant Neurospora porin into liposomes containing, or lacking, the native fungal sterol ergosterol. In both types of liposomes, insertion of the protein converts it to a protease-resistant state and low levels of dimeric and trimeric forms are observed. There are only minor differences between the secondary structural components of the protein in the presence or absence of sterol. Ergosterol in proteoliposomes alters their osmotic responses to sucrose, possibly due to increased membrane rigidity or interactions with the protein that were not revealed by the methods used in this study. The presence of ergosterol is associated with an increased change in conformation and loss of function of liposome-embedded porin at high temperature. Taken with other evidence for direct interactions of sterols with porins, these results support a link between these two molecules in mitochondrial membrane activity.
Cold-active extracellular alkaline protease from an alkaliphilicStenotrophomonas maltophilia: production of enzyme and its industrial applications
Authors: Kuddus Mohammed , Ramteke Pramod W.
Published: November 2009

A novel psychro-tolerant bacterium Stenotrophomonas maltophilia (MTCC 7528) with an ability to produce extracellular, cold-active, alkaline, and detergent-stable protease was isolated from soil samples obtained from Gangotri glacier, Western Himalaya, India. The culture conditions for higher protease production were optimized with respect to incubation time, agitation, substrate, pH, and temperature. Maximum protease production of 56.2 U·mL–1was achieved in the medium at 20 °C and pH 9.0 after 120 h incubation. The protease was partially purified by ion-exchange chromatography and approximately 55-fold purification was achieved. The purified enzyme was a 75 kDa protease with maximum activity and stability at pH 10 and 20 °C. The activity of enzyme is stimulated by Mn2+and inhibited completely by metalloprotease inhibitors, indicating that it is a metalloprotease. The protease showed excellent stability and compatibility with commercial detergents and exhibited high efficiency for the removal of different types of protein-containing stains at low temperature. The wash performance analysis of blood and grass stains on cotton fabric showed an increase in reflectance by 26% and 23%, respectively, after treatment with enzyme in comparison to detergent only. These results indicate that it may be a potential component to use as a detergent additive for cold washing and in environmental bioremediation in cold regions.
Rapid method for extracting the antibiotic mutacin 1140 from complex fermentation medium yeast extract
Authors: Chaney Noel , Wilson-Stanford Shawanda , Kastrantas James , Dahal Neeti , Smith Leif
Published: November 2009

The peptide antibiotic mutacin 1140 belongs to the group of antibiotics called lantibiotics. They are ribosomally synthesized and undergo extensive enzymatic modifications before being excreted into the culture medium. By using reverse-phase – high-performance liquid chromatography (RP–HPLC) and a semiquantitative bacteriocin bioassay to track mutacin 1140, an efficient ammonium sulfate (AS) precipitation method has been developed for removing mutacin 1140 from a complex medium containing 5% yeast extract. This method minimizes the amounts of fermentation by-products and media components that make downstream purification processes more difficult and economically infeasible. The method may be adaptable for the initial purification step of other lantibiotics. A threefold decrease in the precipitation of the medium components found in yeast extract, at pH 8.0 vs. pH 2.0, may have broad utility for the isolation of secondary metabolites produced in this complex medium. The average yield of mutacin 1140 from the fermentation medium was determined as 66%.