bluuebunny/crossref_metadata_2025 huggingface dataset:
Hepatitis C Virus (HCV)-Induced Immunoglobulin Hypermutation Reduces the Affinity and Neutralizing Activities of Antibodies against HCV Envelope Protein
Authors: Machida Keigo , Kondo Yasuteru , Huang Jeffrey Y. , Chen Yung-Chia , Cheng Kevin T.-H. , Keck Zhenyong , Foung Steven , Dubuisson Jean , Sung Vicky M.-H. , Lai Michael M. C.
Published: April 2008

Hepatitis C virus (HCV) often causes persistent infection despite the presence of neutralizing antibodies against the virus in the sera of hepatitis C patients. HCV infects both hepatocytes and B cells through the binding of its envelope glycoprotein E2 to CD81, the putative viral receptor. Previously, we have shown that E2-CD81 interaction induces hypermutation of heavy-chain immunoglobulin (
V

H

) in B cells. We hypothesize that if HCV infects antibody-producing B cells, the resultant hypermutation of

V
H

may lower the affinity and specificity of the HCV-specific antibodies, enabling HCV to escape from immune surveillance. To test this hypothesis, we infected human hybridoma clones producing either neutralizing or non-neutralizing anti-E2 or anti-E1 antibodies with a lymphotropic HCV (SB strain). All of the hybridoma clones, except for a neutralizing antibody-producing hybridoma, could be infected with HCV and support virus replication for at least 8 weeks after infection. The

V
H

sequences in the infected hybridomas had a significantly higher mutation frequency than those in the uninfected hybridomas, with mutations concentrating in complementarity-determining region 3. These mutations lowered the antibody affinity against the targeting protein and also lowered the virus-neutralizing activity of anti-E2 antibodies. Furthermore, antibody-mediated complement-dependent cytotoxicity with the antibodies secreted from the HCV-infected hybridomas was impaired. These results suggest that HCV infection could cause some anti-HCV-antibody-producing hybridoma B cells to make less-protective antibodies.
Cytomegalovirus Proteins vMIA and m38.5 Link Mitochondrial Morphogenesis to Bcl-2 Family Proteins
Authors: Norris Kristi L. , Youle Richard J.
Published: April 2008

Apoptosis is a host defense mechanism against viruses that can be subverted by viral gene products. Human cytomegalovirus encodes viral mitochondria-localized inhibitor of apoptosis (vMIA; also known as pUL37x1), which is targeted to mitochondria and functions as a potent cell death suppressor by binding to and inhibiting proapoptotic Bcl-2 family members Bax and Bak. vMIA expression also dramatically alters mitochondrial morphology, causing the fragmentation of these organelles. A potential ortholog of vMIA, m38.5, which was identified in murine cytomegalovirus, has been shown to localize to mitochondria and protect against chemically induced apoptosis by unknown mechanisms. Despite sharing negligible homology with vMIA and no region detectably corresponding to the vMIA Bax-binding domain, we find that m38.5, like vMIA, binds to Bax and recruits Bax to mitochondria. Interestingly, m38.5 and vMIA appear to block Bax downstream of translocation to mitochondria and after an initial stage of Bax conformational change. In contrast to vMIA, m38.5 neither binds to Bak nor causes mitochondrial fragmentation. Consistently with Bax-selective inactivation by m38.5, m38.5 fragments mitochondria in Bak knockout (KO) cells and protects Bak KO cells from apoptosis better than Bax KO cells. Thus, vMIA and m38.5 share some, but not all, features of apoptosis regulation through Bcl-2 family interaction and allow the dissection of Bax translocation into discrete steps.
Occupation and male infertility: glycol ethers and other exposures
Authors: Cherry N , Moore H , McNamee R , Pacey A , Burgess G , Clyma J-A , Dippnall M , Baillie H , Povey A ,   participating centres of Chaps-UK
Published: April 2008

Objectives:

To investigate the relation between male infertility and occupational exposures, particularly glycol ethers.

Methods:

A case-referent study was designed in which men attending 14 fertility clinics in 11 centres across the UK in 1999–2002 were recruited following 12 months of unprotected intercourse and without a previous semen analysis. Cases were those with low motile sperm concentration (MSC) relative to the time since their last ejaculation (MSC <12×106 for 3 days of abstinence). Referents were other men attending these clinics and meeting the inclusion criteria. A single semen sample was collected at the clinic and analysed at the andrology laboratory serving each hospital. Concentration was determined manually with motility assessed centrally from video recordings. Exposures and confounding factors were assessed from self-completed and nurse–interviewer questionnaires, completed prior to the results of the semen analysis. The occupational histories were assessed for exposures relative to UK norms by a team of occupational hygienists blind to case status.

Results:

Of 2118 men in employment at the time of the interview, 874 (41.3%) were cases. Work with organic solvents, particularly glycol ethers, in the 3 months before the first clinic visit was associated with the likelihood of low motile sperm count. Unadjusted odds ratios (OR) for moderate and high glycol ether exposure (compared with none) were 1.70 (95% CI: 1.11 to 2.61) and 2.54 (95% CI: 1.24 to 5.21). Adjustment for potential confounders (surgery to the testes, previous conception, wearing boxer shorts, drinking alcohol, employed in manual work) reduced the risk associated with glycol ether exposure: moderate OR = 1.46 (95% CI: 0.93 to 2.28), high OR = 2.25 (95% CI: 1.08 to 4.69). No other occupational risk factor was identified.

Conclusions:

Glycol ether exposure was related to low motile sperm count in men attending fertility clinics. This suggests that, at the time of the study, glycol ethers continued to be a hazard for male fertility.
Meta-analysis of benzene exposure and non-Hodgkin lymphoma: biases could mask an important association
Authors: Steinmaus C , Smith A H , Jones R M , Smith M T
Published: April 2008

Objectives:

Benzene is a widely recognised cause of leukaemia but its association with non-Hodgkin’s lymphoma (NHL) is less well established. The goal of this project is to review the current published literature on this association.

Methods:

We performed a meta-analysis of cohort and case-control studies of benzene exposure and NHL and a meta-analysis of NHL and refinery work, a potential source of benzene exposure.

Results:

In 22 studies of benzene exposure, the summary relative risk for NHL was 1.22 (95 CI 1.02 to 1.47; one-sided p value  0.01). When studies that likely included unexposed subjects in the “exposed” group were excluded, the summary relative risk increased to 1.49 (95 CI 1.12 to 1.97, n  13), and when studies based solely on self-reported work history were excluded, the relative risk rose to 2.12 (95 CI 1.11 to 4.02, n  6). In refinery workers, the summary relative risk for NHL in all 21 studies was 1.21 (95 CI 1.00 to 1.46; p  0.02). When adjusted for the healthy worker effect, this relative risk estimate increased to 1.42 (95 CI 1.19 to 1.69).

Conclusions:

The finding of elevated relative risks in studies of both benzene exposure and refinery work provides further evidence that benzene exposure causes NHL. In addition, the finding of increased relative risks after removing studies that included unexposed or lesser exposed workers in “exposed” cohorts, and increased relative risk estimates after adjusting for the healthy worker effect, suggest that effects of benzene on NHL might be missed in occupational studies if these biases are not accounted for.
Chronic health problems and risk of accidental injury in the workplace: a systematic literature review
Authors: Palmer K T , Harris E C , Coggon D
Published: April 2008

Objectives:

To investigate whether common important health conditions and their treatments increase risks of occupational injury.

Methods:

A systematic search was conducted of MEDLINE, EMBASE and PsycINFO databases from inception to November 2006 employing terms for occupational injury, medications, and a broad range of diseases and impairments. Papers related solely to driving, alcohol, or substance abuse were excluded, as were studies that did not allow analysis of injury risk. For each paper that was retrieved we abstracted standard information on the population, design, exposure(s), outcome(s), response rates, confounders and effect estimates; and rated the quality of information provided.

Results:

We found 38 relevant papers (33 study populations): 16 studies were of cross-sectional design, 13 were case-control and 4 were prospective. The overall quality was rated as excellent for only two studies. Most commonly investigated were problems of hearing (15 studies), mental health (11 studies) and vision (10 studies).

For impaired hearing, neurotic illness, diabetes, epilepsy and use of sedating medication there were moderate positive associations with occupational injury (odds ratios 1.5–2.0), but there were major gaps in the evidence base. Studies covering vision did not present risks by category of eye disease; no evidence was found on psychotic illness; for diabetes, epilepsy and cardiovascular disease there were remarkably few papers; studies seldom distinguished risks by sub-category of external cause or anatomical site and nature of injury; and exposures and outcomes were mostly ascertained by self-report at a single time point, with a lack of clarity about exposure timings.

Conclusion:

Improved research is needed to define the risks of occupational injury arising from common health complaints and treatments. Such research should delineate exposures and outcomes in more detail, and ensure by design that the former precede the latter.
CEPHALOSPORIUM CANKER OF WESTERN HEMLOCK
Authors: Denyer W. B. G.
Published: April 2008

A stem canker of suppressed western hemlock (Tsuga heterophytta (Raf.) Sarg.) was found at Powell River and Turnour Island, British Columbia. The canker, which appears to be annual, is irregularly elliptical with conspicuous resinosis in the early stages of development. A species of Cephalosporium was consistently isolated from the canker. Inoculation of western hemlock with this fungus produced cankers similar to those of natural origin. The growth and hyphal characters and the temperature–growth relations of the fungus are described. Attempts to produce the perfect stage in culture were unsuccessful.
NINETEEN BOGS FROM SOUTHERN QUEBEC
Authors: Potzger J. E.
Published: April 2008

The 19 pollen profiles from the Gaspé and the St. Lawrence Valley show close correlation with known facts in glacial geology of this region. Marine invasions and persistence of the Laurentian icecap prevented forest occupation until climate had warmed considerably. The warm period was followed by a deteriorating climate as shown by rise in spruce and fir. During the succeeding very warm period, spruce and fir became rare, pine increased in the Gaspé region, and hemlock and broadleaved trees associated with pine became important in the St. Lawrence Valley, while the forests on the lower Laurentian Shield were composed primarily of pine penetrated by hemlock and broadleaved genera as minor elements. During most recent times the climate has become colder. Spruce and fir show a decided peak, especially in the Gaspé and on the Shield, pine declined in all parts of Quebec, but broadleaved genera, including chestnut in some areas, became prominent in the St. Lawrence Lowland, while decline of hemlock and pine and increase of spruce, fir, and yellow birch mark the forests on the southern slopes of the Shield. Pollen profiles are favorably correlated with forest divisions of Halliday.
THE ACTION OF WIND IN THE DISPERSAL OF SPORES FROM CUP-SHAPED PLANT STRUCTURES
Authors: Brodie Harold J. , Gregory P. H.
Published: April 2008

Observation of Lycopodium spores in glass vessels of various sizes and shapes subjected to winds ranging from 0.6 to 7.1 meters per second showed that spores are blown from funnel or egg-cup-shaped vessels more readily than from rectangular vessels or horizontal glass slides. Lycopodium spores were not visibly dispersed from a conical funnel with mouth 4 cm. diameter at wind speeds below 3 meters per second. Soredia of the lichen Cladonia were blown out of their funnel-shaped podetia by winds of 1.5–2 meters per second (3.3–5.3 miles per hr.) although no soredia were blown from a horizontal glass slide at the same wind speeds. When smoke flowed over conical glass funnels in a wind tunnel, two eddy systems were observed. The first took the form of twin vortices with almost vertical axes, one on either side of the median line in the funnel. Each vortex was smallest at the narrowest part of the funnel and widened upwards. The second system was a single permanent elliptical eddy with horizontal axis near the funnel mouth. The upper side of this eddy moved with the wind, the lower against it. Thus, across the median line of the funnel parallel with the air stream but in the opposite direction, there is a flow of air made up of the mingling of the bottom part of the permanent elliptical eddy and the inner edges of the two vortices. It is assumed that, in nature, the two eddy systems created by wind blowing over funnel-shaped plant structures will effectively remove spores and bodies of comparable size. The twin vortices suck spores from the bottom of the funnel and the rotation of the upper elliptical eddy raises the spores along the upwind wall of the funnel and ejects them into the wind above. In a hemispherical plant structure, a single permanent eddy carries spores backwards and up the upwind surface. This kind of dispersal could occur in a variety of plants, including Discomycetes and wind-pollinated plants.
MARSH AND BOG VEGETATION IN NORTHWESTERN ALBERTA
Authors: Moss E. H.
Published: April 2008

Swamp, marsh, wet meadow, saline meadow, Drepanocladus bog, and Sphagnum bog are characterized and related aquatic vegetation is described briefly. There is succession from different kinds of swamp and marsh, through wet meadow, to Agropyron–Carex grassland and to various wooded communities, and also of marsh, through Drepanocladus–Carex bog to a Larix laricina association. The main bog sere of the region is initiated by some kind of aquatic or marsh phase and passes through Sphagnum bog stages to bog forest (Picea mariana) climax. Ecological aspects of Sphagnum species are considered in relation to succession and a regeneration cycle. Retrogression caused by burning is described for marshes, bogs, and bog forests. Many bogs in the northern part of the region have large mounds and ridges that retain frozen peat below the surface mantle during the summer. The significance of these permafrost areas is discussed. Brief consideration is given to phytogeographical features of the region.
Estimating calcium weathering rates and future lake calcium concentrations in the Muskoka–Haliburton region of Ontario
Authors: Watmough Shaun A , Aherne Julian
Published: April 2008

Calcium (Ca) concentrations in surface waters on the Precambrian Shield are determined primarily by the Ca weathering rate in soil, which requires extensive soil data that generally do not exist. From a water chemistry database comprising approximately 550 lakes in south-central Ontario, Canada, 130 lakes were selected with low Ca concentrations (Ca < 75 µmol·L–1). Calcium weathering is primarily dominated by silicate minerals such as plagioclase and hornblende, allowing the use of Ca–sodium (Na) ratios in lake water to estimate Ca weathering rates. Soil profile data at seven sites indicated that the Ca–Na ratio from mineral weathering is 0.86; correspondingly, Ca weathering rates in lakes ranged from 0.04 to 0.24 kmol·ha–1·year–1 (median of 0.09 kmol·ha–1·year–1). This compares with a range of 0.06–0.24 kmol·ha–1·year–1 (median of 0.14 kmol·ha–1·year–1) obtained using the steady-state water chemistry model. Using these methods to bound potential weathering rates, Ca concentrations in individual lakes at steady state are predicted to decline by 10%–40% compared with current values. Dynamic soil hydrochemical model predictions indicate that Ca concentrations in lakes will be considerably lower than these steady-state predictions within decades if timber harvesting occurs in the drainage basins.
Catch-and-release and size limit regulations for blue, white, and striped marlin: the role of postrelease survival in effective policy design
Authors: Pine III William E , Martell Steven J.D. , Jensen Olaf P , Walters Carl J , Kitchell James F
Published: April 2008

Catch-and-release fishing as a management and conservation tool for billfish (family Istiophoridae) is practiced in many recreational fisheries, and mandatory release of billfish has been implemented for some commercial fisheries. Inherent in these approaches is the observation that survival of released fish is greater than those that are landed. Recent studies using pop-up satellite tags have begun to quantify postrelease survival rates for billfish, yet the efficacy of management measures that require some or all billfish to be released have not been evaluated. Using an age- and size-structured population model that accounts for individual variability in growth, we simulated the effects of postrelease mortality on yield, risk of recruitment overfishing, efficiency (i.e., ratio of harvest to postrelease mortality), and probability of catching trophy-sized individuals for three marlin species. Regulations such as size limits, catch-and-release, and mandatory release are likely to provide some benefit to billfish populations, but our results show that the effectiveness of these strategies is reduced when release survival is less than 100%. The management approaches most likely to benefit billfish populations are ones that focus on maximizing postrelease survival in the recreational fishery and minimize the billfish catch in commercial fisheries.
Difference in the Seawater Tolerance of Anadromous and Landlocked Populations of Arctic Char (Salvelinus alpinus)
Authors: Staurnes Magne , Sigholt Trygve , Lysfjord Grete , Gulseth Odd A.
Published: April 2008

The seawater tolerance of juvenile fish from an anadromous and a landlocked population of Arctic char (Salvelinus alpinus), reared in freshwater under a constant light regime, was compared by making repeated seawater challenge tests from one summer to the next. Fish from the landlocked population had higher mortality rates and higher blood plasma Na+concentrations after transfer to seawater than those from the anadromous population. The gill Na-K-ATPase activity of the landlocked fish was lower than that of the anadromous fish. For both populations, the smallest fish showed the lowest seawater tolerance, but hypoosmoregulatory ability was independent of fish size for fish larger than about 60 g. By June of the second summer, fish from the anadromous, but not those from the landlocked population, developed seawater tolerance 10 d after transfer to seawater. This increase in hypoosmoregulatory ability was accompanied by a doubling of the gill Na-K-ATPase activity.
Annual Variations in Rheotactic Behaviour and Seawater Adaptability in Landlocked Arctic Char (Salvelinus alpinus)
Authors: Schmitz Monika
Published: April 2008

The existence of basic smoltification characteristics, measured by means of seasonal changes in rheotactic behaviour and seawater adaptability, was studied from February to November in 1- and 2-yr-old landlocked Arctic char (Salvelinus alpinus). Up- and downstream directed movements were monitored in an annular stream tank at a water velocity of 0.2 m/s. A 48-h seawater challenge test using 25‰ seawater was performed at monthly intervals throughout the year to assess seawater adaptability. The 1-yr-old char displayed mainly nondirectional behaviour during spring, but from August onwards the movements were predominantly against the current. Seawater performance improved slightly in this group in May and June. The 2-yr-old char progressively developed a downstream behaviour and exhibited an increased seawater adaptability during spring and early summer. In late August, a marked reversal in rheotactic behaviour occurred, followed by a rapid decrease in seawater tolerance. The results demonstrate that seasonal changes in seawater adaptability and changes in migratory behaviour which were directionally consistent with smolting still exist in a population of Arctic char that has been landlocked for about 6000 yr.
Recruitment of the 1987 Year Class of Georges Bank Haddock (Melanogrammus aeglefinus): The Influence of Unusual Larval Transport
Authors: Polacheck T. , Mountain D. , McMillan D. , Smith W. , Berrien P.
Published: April 2008

Unusually strong along-shelf surface flow in the spring of 1987 transported haddock (Melanogrammus aeglefinus) larvae westward from spawning grounds on Georges Bank into the Middle Atlantic Bight, some as far as 400 km beyond the limits of their normal distribution. 0-Group haddock survived in the Bight in record numbers. Their center of abundance occurred along the outer half of the shelf from Delaware Bay to Martha's Vineyard where more than 97% of the 0-group fish resided in the fall of 1987. Juveniles remained more abundant in the Bight than on the bank through the spring of 1988. Collective evidence suggests that survivors returned to Georges Bank during the late spring/early summer of 1988. The estimated number of 0-group fish in the 1987 year class exceeded all previous estimates from a 27-yr time series which included the 1963 year class, the largest recruited to the fishery since record keeping began in 1931.
Neomysis americana (Crustacea: Mysidacea) as an Intermediate Host for Sealworm, Pseudoterranova decipiens (Nematoda: Ascaridoidea), and Spirurid Nematodes (Acuarioidea)
Authors: Marcogliese David J.
Published: April 2008

Amphipods (Gammarus oceanicus) and mysids (Neomysis americana) were collected from three brackish ponds on Sable Island, 290 km east of Halifax, Nova Scotia. Thirteen nematodes were recovered from 3950 mysids subjected to enzymatic digestion. Four of the nematodes were identified as larval sealworm (Pseudoterranova decipiens). The remaining nematodes belong to two species: Paracuaria adunca and Cosmocephalus obvelatus (Acuarioidea). This is the first record of N. americana as an intermediate host for P. decipiens. It is also the first report of a mysid as intermediate host for either of the acuarioid nematodes and the first evidence of these two nematodes undergoing part of their life cycles in brackish or marine conditions. No nematodes were observed in 2364 amphipods or 1462 mysids examined microscopically, but unidentified metacercariae were found in 1.9% of the amphipods.
Diel Pelagic Foraging by a Pandalid Shrimp (Pandalus montagui) off Resolution Island (Eastern Hudson Strait)
Authors: Hudon C. , Parsons D. G. , Crawford R.
Published: April 2008

The vertical distribution and diet of shrimp (Pandalus montagui) were investigated using a multistage plankton sampler (BIONESS) and were compared with those of shrimp captured on the bottom using a trawl. Massive nocturnal vertical migrations of shrimp were observed in association with intense pelagic feeding activity. The sex ratio, size frequency distribution, and diet of shrimp caught in the water column differed markedly from shrimp caught during their stay on the bottom. Pelagic migrants were mostly males (75%), extending their planktonic foray into morning hours, whereas ovigerous (12%) and nonovigerous (13%) females returned to the bottom at dawn. In the trawl, the representation of males (43%) and ovigerous females (45%) differed, but also fluctuated on a diel cycle. Stomachs of shrimp captured in the BIONESS were fuller and the contents were in better condition than found in shrimps captured in the bottom trawl. Pelagic shrimp fed opportunistically on a variety of zooplankters, using copepods as a staple food. Stomachs of shrimp from the bottom trawl contained chitinous debris, sand grains, and small amounts of benthic organisms. The occurrence of daily vertical feeding migrations results in the unavailability of a variable proportion of the total shrimp biomass to bottom trawls.
Population Dynamics, Numerical Production, and Potential Predation Impact on a Meiobenthic Copepod
Authors: Morris James T. , Coull Bruce C.
Published: April 2008

From the fecundity and temperature-dependent development times of the life stages of Microarthridion littorale and long-term measurements of the densities of copepodites and female and male adults in subtidal sediments at North Inlet, South Carolina, we calculated maximum and minimum productivity limits of this meiobenthic copepod. The potential production of numbers of nauplii (10 002 × 103∙m−2∙yr−1) exceeds the population density and production of copepodites and adults by about 2 orders of magnitude; observed populations of copepodites and adults can be supported even with a 98% mortality of nauplii. This suggests that predation or other causes of nauplii mortality limits the population density of M. littorale at North Inlet. The potential dry biomass production of nauplii is about 2.0 g∙m−2∙yr−1and greatly exceeds the combined biomass production of copepodites and adults. Because the minimum numerical productivity (that required to explain the temporal changes in population size) of adults (38 × 103∙m−2∙yr−1) is 26% of the maximum potential adult productivity (derived from the maturation of copepodites), it is likely that adult densities are regulated by recruitment. A time series of population data indicates large interannual variations in production of the different developmental stages, with potential naupliar recruitment showing the greatest variability.
Analysis of sugarcane mosaic virus resistance in maize in an isogenic dihybrid crossing scheme and implications for breeding potyvirus-resistant maize hybrids
Authors: Xing Yongzhong , Ingvardsen Christina , Salomon Raphael , Lübberstedt Thomas
Published: April 2008

The gene action of 2 sugarcane mosaic virus (SCMV) resistance loci in maize, Scmv1 and Scmv2, was evaluated for potyvirus resistance in an isogenic background. All 4 homozygous and 5 heterozygous isogenic genotypes were produced for introgressions of the resistant donor (FAP1360A) alleles at both loci into the susceptible parent (F7) genetic background using simple sequence repeat markers. For SCMV and maize dwarf mosaic virus (MDMV), virus symptoms appeared rapidly in the 3 homozygous genotypes, with susceptibility alleles fixed at 1 or both loci. Although the 9 isogenic genotypes revealed a high level of resistance to Zea mosaic virus (ZeMV), the same 3 homozygous genotypes were only partially resistant. This indicates that 1 resistance gene alone is not sufficient for complete resistance against SCMV, MDMV, and ZeMV. Scmv1 showed strong early and complete dominant gene action to SCMV, but it gradually became partially dominant. Scmv2 was not detected at the beginning, showing dominant gene action initially and additive gene action at later stages. Both genes interacted epistatically (for a high level of resistance, at least 1 resistance allele at each of both loci is required). This implies that double heterozygotes at the 2 loci are promising for producing SCMVresistant hybrids. Results are discussed with respect to prospects for isolation of SCMV and MDMV resistance genes.
Integration of microsatellite-based genetic maps for the turkey (Meleagris gallopavo)
Authors: Reed K.M. , Chaves L.D. , Knutson T.P. , Krueth S.B. , Ashwell C.M. , Burt D.W.
Published: April 2008

Integration of turkey genetic maps and their associated markers is essential to increase marker density in support of map-based genetic studies. The objectives of this study were to integrate 2 microsatellite-based turkey genetic maps — the Roslin map and the University of Minnesota (UMN) map — by genotyping markers from the Roslin study on the mapping families of the UMN study. A total of 279 markers was tested, and 240 were subsequently screened for polymorphisms in the UMN/Nicholas Turkey Breeding Farms (NTBF) mapping families. Of the 240 markers, 89 were genetically informative and were used for genotyping the F2 offspring. Significant genetic linkages (log of odds > 3.0) were found for 84 markers from the Roslin study. BLASTn comparison of marker sequences with the draft assembly of the chicken genome found 263 significant matches. The combination of genetic and in silico mapping allowed for the alignment of all linkage groups of the Roslin map with those of the UMN map. With the addition of the markers from the Roslin map, 438 markers are now genetically linked in the UMN/NTBF families, and more than 1700 turkey sequences have now been assigned to likely positions in the chicken-genome sequence.
Mapping of the apple scab-resistance gene Vb
Authors: Erdin N. , Tartarini S. , Broggini G.A.L. , Gennari F. , Sansavini S. , Gessler C. , Patocchi A.
Published: April 2008

Apple scab, caused by the fungus Venturia inaequalis , is the major production constraint in temperate zones with humid springs. Normally, its control relies on frequent and regular fungicide applications. Because this control strategy has come under increasing criticism, major efforts are being directed toward the breeding of scab-resistant apple cultivars. Modern apple breeding programs include the use of molecular markers, making it possible to combine several different scab-resistance genes in 1 apple cultivar (pyramiding) and to speed up the breeding process. The apple scab-resistance gene Vb is derived from the Siberian crab apple ‘Hansen’s baccata #2’, and is 1 of the 6 “historical” major apple scab-resistance genes (Vf, Va, Vr, Vbj, Vm, and Vb). Molecular markers have been published for all these genes, except Vr. In testcross experiments conducted in the 1960s, it was reported that Vb segregated independently from 3 other major resistance genes, including Vf. Recently, however, Vb and Vf have both been mapped on linkage group 1, a result that contrasts with the findings from former testcross experiments. In this study, simple sequence repeat (SSR) markers were used to identify the precise position of Vb in a cross of ‘Golden Delicious’ (vbvb) and ‘Hansen’s baccata #2’ (Vbvb). A genome scanning approach, a fast method already used to map apple scab-resistance genes Vr2 and Vm, was used, and the Vb locus was identified on linkage group 12, between the SSR markers Hi02d05 and Hi07f01. This finding confirms the independent segregation of Vb from Vf. With the identification of SSR markers linked to Vb, another major apple scab-resistance gene has become available; breeders can use it to develop durable resistant cultivars with several different resistance genes.
Carcass rendering systems for farm mortalities: A review
Authors: Kalbasi-Ashtari A. , Schutz M.M. , Auvermann B.W.
Published: April 2008

Improper animal-mortality disposal may allow pathogenic microorganisms to spread diseases in soil, plants, animals, and to humans;; and resulting odor reduces the quality of life for neighbors. Health hazards posed by neglect in carcass disposal would be pronounced in the event of a natural catastrophe, disease outbreak or intentional depopulation of herds or flocks. Conventional rendering systems have been utilized for the last two decades to convert various animal carcasses to different products. However, considerations regarding prion diseases will further shape the rendering industry. New rendering technologies that convert suspected prion-infected animal tissues into tallow and protein for use as a biofuel and fertilizer, respectively, are beginning to emerge. This paper reviews the rendering industry and new methods for carcass rendering to produce safe and economically valuable products while minimizing impacts on public safety and environmental quality.
Efficient syntheses of four chiral phenylcyclopropanes
Authors: Baldwin John E , Singer Stephanie R
Published: April 2008

An efficient four-step synthetic route from each of four crystalline isotopically labeled (1R)-menthyl (1S,2S)-(+)-2-phenylcyclopropanecarboxyates of better than 99% enantiomeric excess has provided multi-gram quantities of the corresponding chiral phenylcyclopropanes. The key transformation involved a bis[1,3-bis(diphenylphosphino)propane]rhodium chloride that catalyzed a highly stereoselective decarbonylation of a trans-2-phenylcyclopropanecarboxaldehyde.Key words: cyclopropanes chiral thanks to isotopic substituents, catalytic decarbonylations of cyclopropanecarboxaldehydes.
Synthesis of constrained aromatic β2,3,3-amino alcohol scaffolds — Precursors of non-proteinogenic phenylalanine for peptidomimetics
Authors: Bhella Surinderjit Singh , Ishar Mohan Paul S. , Singh Gajendra , Singh Rajinder , Singh Gurpinder , Raj Tilak
Published: April 2008

Novel constrained β2,3,3-amino alcohol scaffolds (11a–11e) with varied substitution patterns have been synthesized by reductive cleavage of the N–O bond of isoxazolidines (10a–10e) derived from intramolecular 1,3-dipolar cycloadditions. A number of methods were probed for reductive cleavage, however, better results were obtained with ammonium formate in the presence of Pd/C or Zn as compared to Zn/acetic acid. The obtained scaffolds (11a–11e) can serve as valuable building blocks for peptidomimetics.Key words: β2,3,3-amino alcohol, peptidomimetics, building blocks, isoxazolidines, reductive cleavage, ammonium formate.
Accelerated syntheses of amine-bis(phenol) ligands in polyethylene glycol or “on water” under microwave irradiation
Authors: Kerton Francesca M , Holloway Stacey , Power Angela , Soper R Graeme , Sheridan Kristina , Lynam Jason M , Whitwood Adrian C , Willans Charlotte E
Published: April 2008

Pure amine-bis(phenol) ligands are readily accessible in high yield, often >90%, when the Mannich condensation reactions are performed “on water” or in poly(ethyleneglycol) (PEG). Microwave-assisted synthesis dramatically reduces the time and energy required to prepare these molecules, typically from 24 h to 5 min. The approach seems to be widely applicable (7 amines and 5 phenols were tested to yield a diverse set of bis(phenol) ligands). Significant improvements in yield were observed for ligands derived from di-tert-amyl and di-tert-butyl phenols, possibly resulting from a hydrophobic effect. Single crystal X-ray diffraction data for the ligand derived from p-cresol and N,N′-dimethylethylenediamine is reported.Key words: amine-phenol, Mannich condensation, on water, microwave, ligand, high-throughput.
Trends in the frequency, extent, and severity of spruce budworm outbreaks in eastern Canada
Authors: Blais J. R.
Published: April 2008

The history of spruce budworm (Choristoneurafumiferana (Clem.)) outbreaks for the past 200 to 300 years, for nine regions in eastern Canada, indicates that outbreaks have occurred more frequently in the 20th century than previously. Regionally, 21 outbreaks took place in the past 80 years compared with 9 in the preceding 100 years. Earlier infestations were restricted to specific regions, but in the 20th century they have coalesced and increased in size, the outbreaks of 1910, 1940, and 1970 having covered 10, 25, and 55 million ha respectively. Reasons for the increase in frequency, extent, and severity of outbreaks appear mostly attributable to changes caused by man, in the forest ecosystem. Clear-cutting of pulpwood stands, fire protection, and use of pesticides against budworm favor fir–spruce stands, rendering the forest more prone to budworm attack. The manner and degree to which each of these practices has altered forest composition is discussed. In the future, most of these practices are expected to continue and their effects could intensify, especially in regions of recent application. Other practices, including large-scale planting of white spruce, could further increase the susceptibility of forest stands. Forest management, aimed at reducing the occurrence of extensive fir–spruce stands, has been advocated as a long-term solution to the budworm problem. The implementation of this measure at a time when man's actions result in the proliferation of fir presents a most serious challenge to forest managers.
Fire effects on shoot growth characteristics of ponderosa pine in Colorado
Authors: Wyant James G. , Laven Richard D. , Omi Philip N.
Published: April 2008

The impact of fire damage on the shoot growth potential of 36 branches on each of nine ponderosa pine (Pinusponderosa Laws.) trees was evaluated after a fall season prescribed surface fire. In the first season after burning, mean fascicle lengths and bud sizes (length and diameter) were greater on trees which received underburning treatment than on unburned trees. No treatment effect was observed on shoot lengths, needle numbers, or fascicle numbers, characters determined in the season of bud formation.
Fuel weights of understory-grown conifers in southern Oregon
Authors: Agee James K.
Published: April 2008

Fuel weight by size classes for five understory coniferous tree species in southern Oregon was estimated using regression equations. Species included Abiesconcolor (Gord. and Glend) Lindl., Abiesmagnified Murr. var. shastensis Lenin., Pinusponderosa Dougl., Pinus contorta Dougl. var. murryana Grev. and Balf., and Tsugamertensiana (Bong.) Carr. Trees ranged from 0.1 to 3 m tall and were selected from "open" and "dense" overstory classes. Live and dead fuels from each tree were segregated into five diameter size classes. Regressions for foliage and total fuel weight are presented using as independent variables groundline diameter, total height, diameter2 × height, and basal area. Coefficients of determination (r2) were high, exceeding 95% for total weight in every case, but tended to decrease as diameter size class increased. Relative shade tolerance of the five species is estimated by comparing open- and dense-grown foliage weight ratios for each species.
Range-wide patterns of allozyme variation in Douglas-fir (Pseudotsugamenziesii)
Authors: Li Peng , Adams W. T.
Published: April 2008

Seeds from 104 geographical locations throughout the range of Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) were analyzed at 20 enzyme loci to determine patterns of genetic variation and to make phylogenetic inferences. On average, the populations were polymorphic at 37% of the loci (range 5.0–65.0). Mean expected heterozygosity was 0.137 (range 0.021–0.239). Of the total genie diversity (HT = 0.182) observed, 24% was due to differentiation among populations. One Mexican population was genetically distinct from the rest of the species, which suggests the possibility of additional Pseudotsuga species in Mexico. The rest of the populations clustered into two groups corresponding to the recognized coastal and interior varieties. In addition, the interior variety separated into northern and southern subgroups near 44° latitude. Transition zones between the varieties were found to be narrower and more abrupt than has been suggested previously. Populations within the coastal variety and the northern interior subgroup averaged higher expected heterozygosity than the southern interior subgroup, but in the southern interior subgroup, populations were much more highly differentiated. Allozyme variation followed a latitudinal cline in the interior variety, but only weak geographical patterning was observed in the coastal variety. In general, genetic diversity decreased towards the periphery of the species range. Range-wide patterns of allozyme variation were similar to those in terpene studies, with the major exception that the Sierra Nevada seed sources in this study were closely aligned with the coastal variety rather than with the interior variety. Range-wide patterns of genetic variation in Douglas-fir largely reflect the evolutionary history of the species as revealed by paleobotanical studies.
Evaluation of three insitu soil nitrogen availability assays
Authors: Hart Stephen C. , Firestone Mary K.
Published: April 2008

Three indices of nitrogen (N) availability were compared in the field over a 1-year period in an old-growth and a young-growth mixed-conifer forest. The indices utilized were ion exchange resin (IER) bags, buried bags, and a core-IER method employing intact soil cores enclosed in tubes capped at both ends by IER bags. The results from all three methods indicated that in the surface mineral soil, N availability was higher in the young-growth stand than in the old-growth stand. However, seasonal patterns of N availability were generally not well correlated among the methods (correlation coefficients ranged from 0.32 to 0.62). For a given amount of net N mineralized in buried bags, more N accumulated on IER bags placed in the young-growth stand than in those placed in the old-growth stand. This was the result of greater net nitrification in the young-growth stand coupled with the greater mobility of [Formula: see text] relative to [Formula: see text] in soil. Ten-month estimates of net N mineralization measured by the core-IER and buried-bag methods were similar in the young-growth stand (about 42 mg•kg soil−1), but the core-IER estimate was almost twice that of the buried-bag estimate in the old-growth stand (31.7 and 16.8 mg•kg soil−1, respectively). The different sensitivities of the core-IER and buried-bag methods to changes in soil moisture and leaching probably account for much of the difference in their N availability estimates. Results from the core-IER method did reflect the effects of leaching; however, soil water content within the core did not follow changes in soil water content effectively. Because of the greater labor involved in using the core-IER method, its use may be most efficacious in high-precipitation environments, or when in-field soil incubations must be conducted for extended periods of time.
Canker formation and decay in sugar maple and paper birch infected by Cerrenaunicolor
Authors: Enebak Scott A. , Blanchette Robert A.
Published: April 2008

Cerrenaunicolor (Bull.: Fr.) Murr. (= Daedaleaunicolor) (Aphyllophorales, Polyporaceae) was found to cause a canker rot on two northern hardwood tree species, sugar maple (Acersaccharum Marsh.) and paper birch (Betulapapyrifera Marsh.). Pathogenicity of the fungus was determined by inoculation and examination of cankers 6 months, 1.5 years, and 2.5 years later. The two isolates used were found to differ in pathogenicity. Chemical and morphological barriers formed to compartmentalize the fungus. A zone of enhanced cell wall lignification and the formation of suberized impervious cells which composed the necrophylactic periderm in the host were observed. Xylem discoloration, callus formation, and periderm layers were more pronounced in maple than in birch. Cerrenaunicolor moved past host barriers via a mass of hyphae which annually penetrated weak points in the necrophylactic periderm and subsequently killed the adjacent cambium. Once past the necrophylactic periderm and into the xylem, C. unicolor was an aggressive decay organism which caused an extensive white rot. In naturally infected trees, columns of decay were two or three times longer than the cankers. Multiple zones of decayed and discolored wood were present in the xylem as a result of repeated attacks by the fungus.
The influence of night temperature under declining photoperiod on bud initiation in black spruce seedlings
Authors: Odlum K. D. , Colombo S. J.
Published: April 2008

The effect of night temperature on the speed of bud initiation in black spruce (Piceamariana (Mill.) B.S.P.) container seedlings was studied. Day lengths were progressively shortened in plant growth chambers to simulate the natural day-length decline that occurs in the fall at latitude 48°N. During the period of day-length decline a constant 26 °C day temperature was maintained, while night temperatures of 5, 7.5, 10, 14, 18, 22, 24, or 26 °C were imposed. When the night temperature was 10–24 °C, first signs of bud initiation were observed in 12–15 days, while 100% bud initiation was attained in 15–22 days. When the night temperature was 5, 7.5, or 26 °C, first bud initiation was observed in 15–22 days, while 100% bud initiation was not attained until 40 days.
Circumferential variation in the relative density of lodgepole pine
Authors: Gonzalez Josefina S.
Published: April 2008

The circumferential variation in the wood relative density of lodgepole pine (Pinuscontorta var. latifolia Engelm.) was examined in eight discs taken at breast height. The purpose was to determine if the present method of analyzing two opposite radial strips from pith to bark was sufficient for estimating the mean density of the disc. Results showed that two samples taken opposite each other would give comparable or better approximation of the mean density of the disc than would three or four samples taken at random.
Effects of added nitrogen on growth of hardwood trees in southern New York
Authors: Stanturf J. A. , Stone Jr. E. L. , McKittrick R. C.
Published: April 2008

Nitrogen fertilization rate trials (0–672 kg/ha) were established in seven second-growth mixed deciduous forest stands in southern New York, on well to somewhat poorly drained soils typical of better hardwood sites, with no history of fire or cultivation. Basal-area growth over 20 years was determined from increment cores of dominant and codominant trees. Significant growth response occurred only for black cherry (Prunusserotina Ehrh.). Nitrogen additions of 168–336 kg/ha increased growth 21% over 5–10 years. Ten-year basal-area growth response of sugar maple (Acersaccharum Marsh.) and white ash (Fraxinusamericana L.) was less than in other fertilization studies. The lack of response is attributed to favorable nitrogen status of the soils, resulting from lack of disturbance over at least the last four decades and, possibly, atmospheric input of nitrogen.
Susceptibility of lodgepole pine to infestation by mountain pine beetles following partial cutting of stands
Authors: Amman Gene D. , McGregor Mark D. , Schmitz Richard F. , Oakes Robert D.
Published: April 2008

not available
INTRODUCTORY LECTURES ON THE EFFECTIVE ONE BODY FORMALISM
Authors: DAMOUR THIBAULT
Published: April 2008

The Effective One Body (EOB) formalism is an analytical approach which aims at providing an accurate description of the motion and radiation of coalescing binary black holes. We present a brief review of the basic elements of this approach.
ELEMENTARY PARTICLE INTERACTION FROM A KALUZA-KLEIN SCHEME
Authors: CIANFRANI FRANCESCO , MONTANI GIOVANNI
Published: April 2008

We discuss properties of particles and fields in a multi-dimensional space-time, where the geometrization of gauge interactions can be performed. As far as spinors are concerned, we outline how the gauge coupling can be recognized by a proper dependence on extra-coordinates and by the dimensional reduction procedure. Finally applications to the Electro-Weak model are presented.
INTRODUCTION TO DIRAC OBSERVABLES
Authors: GIESEL KRISTINA
Published: April 2008

We give a brief introduction to Dirac observables and review the general construction of such Dirac observables for constrained systems in the framework of the Relational Formalism introduced by Rovelli1 and further mathematically developed by Dittrich.2 Finally we birefly discuss appropriate clocks for General Relativity and the evolution of observables generated by a so called physical Hamiltonian.
THE ROLE OF THE TIME GAUGE IN THE SECOND-ORDER FORMALISM
Authors: CIANFRANI FRANCESCO , MONTANI GIOVANNI
Published: April 2008

We perform a canonical quantization of gravity in a second-order formulation, taking as configuration variables those describing a 4-bein, not adapted to the space-time splitting. We outline how, neither if we fix the Lorentz frame before quantizing, nor if we perform no gauge fixing at all, is invariance under boost transformations affected by the quantization.
QUANTUM COSMOLOGY WITH A MINIMAL LENGTH
Authors: BATTISTI MARCO VALERIO , MONTANI GIOVANNI
Published: April 2008

Quantum cosmology in the presence of a fundamental minimal length is analyzed in the context of the flat isotropic and the Taub cosmological models. Such minimal scale comes out from a generalized uncertainty principle and the quantization is performed in the minisuperspace representation. Both the quantum Universes are singularity-free and (i) in the isotropic model no evidences for a Big-Bounce appear; (ii) in the Taub one a quasi-isotropic configuration for the Universe is predicted by the model.