bluuebunny/crossref_metadata_2025 huggingface dataset:
Nursing and genetic health care
Authors: Lea Dale Halsey , Williams Janet K. , Tinley Susan T.
Published: April 2005

Advances in DNA technology are leading to major developments in nursing practice in clinical genetics, including the creation of new roles for nurses who care for people with genetic conditions. Application of genetic information and testing is moving genetics into the mainstream of health care. Therefore, it is anticipated that nurses in all areas of practice will become involved in the provision of information about genetic testing and assisting individuals and families in decision making and adjustment to new genetic information. This article provides an overview of the profession of nursing which may be useful to genetic counselors in the development of collaborative relationships between the two professions.
EISCAT/CRRES observations: nightside ionospheric ion outflow and oxygen-rich substorm injections
Authors: Gazey N. G. J. , Lockwood M. , Grande M. , Perry C. H. , Smith P. N. , Coles S. , Aylward A. D. , Bunting R. J. , Opgenoorth H. , Wilken B.
Published: April 2005

Abstract. We present combined observations made near midnight by the EISCAT radar, all-sky cameras and the combined released and radiation efects satellite (CRRES) shortly before and during a substorm. In particular, we study a discrete, equatorward-drifting auroral arc, seen several degrees poleward of the onset region. The arc passes through the field-aligned beam of the EISCAT radar and is seen to be associated with a considerable upflow of ionospheric plasma. During the substorm, the CRRES satellite observed two major injections, 17 min apart, the second of which was dominated by O+ ions. We show that the observed arc was in a suitable location in both latitude and MLT to have fed O+ ions into the second injection and that the upward flux of ions associated with it was sufficient to explain the observed injection. We interpret these data as showing that arcs in the nightside plasma-sheet boundary layer could be the source of O+ ions energised by a dipolarisation of the mid- and near-Earth tail, as opposed to ions ejected from the dayside ionosphere in the cleft ion fountain.
Study of sporadic-E clouds by backscatter radar
Authors: Houminer Z. , Russell C. J. , Dyson P. L. , Bennett J. A.
Published: April 2005

Abstract. It is shown that swept-frequency backscatter ionograms covering a range of azimuths can be used to study the dynamics of sporadic-E clouds. A simple technique based on analytic ray tracing can be used to simulate the observed narrow traces associated with Es patches. This enables the location and extent of the sporadic-E clouds to be determined. The motion of clouds can then be determined from a time sequence of records. In order to demonstrate the method, results are presented from an initial study of 5 days of backscatter ionograms from the Jindalee Stage B data base obtained during March-April 1990. Usually 2–3 clouds were observed each day, mainly during the evening and up to midnight. The clouds lasted from 1–4 h and extended between 30°–80° in azimuth and 150-800 km in range. The clouds were mostly stationary or drifted generally westward with velocities of up to 80 m s–1. Only one cloud was observed moving eastward.
Studies of an artificially generated electrode effect at ground level
Authors: Mareev E. A. , Israelsson S. , Knudsen E. , Kalinin A. V. , Novozhenov M. M.
Published: April 2005

Abstract. The outdoor experiments, using a metallic grid above the ground surface, have yielded well-defined vertical profiles of the space-charge density. The profiles showed strong evidence for the existence of an electrode effect, which could be named the artificial electrode effect and can serve as a very useful and well-controlled model for the study of atmospheric electric processes in the atmospheric surface layer. The build-up or break-down of an electrode-effect layer occurred in a time of the order of 10 s under the experimental conditions realized. The artificially generated electrode effect is dependent on the electrical field strength supplied, wind speed, turbulent mixing and ion mobilities. Wind speed and ion mobility seem to be the dominant factors, defining space-charge density profiles. A theoretical model for the artificial electrode effect has been developed, taking into account turbulent mixing of charged particles in the air flow with the logarithmic profile of the wind velocity. The numerical analysis of the boundary value problem for the two-dimensional equations for the light ion concentrations has been performed. The model presented shows a qualitative agreement of calculated space-charge profiles with measured ones, and explains the dependence of the artificial electrode effect on the dominant control parameters. The limiting conditions for the developed theory are discussed.
ATP potentiates the formation of AChR aggregate in the co‐culture of NG108‐15 cells with C2C12 myotubes
Authors: Ling Karen K.Y. , Siow Nina L. , Choi Roy C.Y. , Tsim Karl W.K.
Published: April 2005

The role of adenosine 5′‐triphosphate (ATP) and P2Y1 nucleotide receptor in potentiating agrin‐induced acetylcholine receptor (AChR) aggregation is being demonstrated in a co‐culture system of NG108‐15 cell, a mouse neuroblastoma X rat glioma hybrid cell line that resembles spinal motor neuron, with C2C12 myotube. In the co‐cultures, antagonized P2Y1 receptors showed a reduction in NG108‐15 cell‐induced AChR aggregation. Parallel to this observation, cultured NG108‐15 cell secreted ATP into the conditioned medium in a time‐dependent manner. Enhancement of ATP release from the cultured NG108‐15 cells by overexpression of active mutants of small GTPases increased the aggregation of AChRs in co‐culturing with C2C12 myotubes. In addition, ecto‐nucleotidase was revealed in the co‐culture, which rapidly degraded the applied ATP. These results support the notion that ATP has a role in directing the formation of post‐synaptic apparatus in vertebrate neuromuscular junctions.
Water and molecular chaperones act as weak links of protein folding networks: Energy landscape and punctuated equilibrium changes point towards a game theory of proteins
Authors: Kovács István A. , Szalay Máté S. , Csermely Peter
Published: April 2005

Water molecules and molecular chaperones efficiently help the protein folding process. Here we describe their action in the context of the energy and topological networks of proteins. In energy terms water and chaperones were suggested to decrease the activation energy between various local energy minima smoothing the energy landscape, rescuing misfolded proteins from conformational traps and stabilizing their native structure. In kinetic terms water and chaperones may make the punctuated equilibrium of conformational changes less punctuated and help protein relaxation. Finally, water and chaperones may help the convergence of multiple energy landscapes during protein–macromolecule interactions. We also discuss the possibility of the introduction of protein games to narrow the multitude of the energy landscapes when a protein binds to another macromolecule. Both water and chaperones provide a diffuse set of rapidly fluctuating weak links (low affinity and low probability interactions), which allow the generalization of all these statements to a multitude of networks.
On the Lagrangian formulations of reactive solute transport in the hydrologic response
Authors: Botter Gianluca , Bertuzzo Enrico , Bellin Alberto , Rinaldo Andrea
Published: April 2005

We address Lagrangian dispersion of reactive solutes in the framework of the formulation of transport by travel time distributions, specifically aiming at models of basin‐scale, nonpoint transport applicable to complex geomorphological settings. We revisit existing exact solutions of the reactive transport problem derived in the convective stochastic framework and extend them to the case of transport of mass arbitrarily distributed (in time and space) within the immobile phase, a situation which is arguably suited to better describe nonpoint source solute transport driven by the hydrologic response. The initial conditions and, particularly, the mass initially stored in immobile rather than mobile phases bear a pronounced effect on the spatial and temporal moments of the solute plume. We also show that in many nonpoint source cases of interest (typically when heterogeneous conditions prevail) a simpler model of reaction kinetics, where spatial gradients in the immobile concentration are neglected, does well. Such a class of models, termed mass response functions, is known from the literature and has the property, beside being simplified in the mass exchange terms, of embedding unsteady flow forcing of the type typically employed in the theory of the hydrologic response. Thus, in the range of cases where the well‐mixed assumption proves meaningful, we suggest a natural extension of current geomorphological models of the hydrologic response to generic transport phenomena.
Imaging the source region of the 2004 mid‐Niigata prefecture earthquake and the evolution of a seismogenic thrust‐related fold
Authors: Kato Aitaro , Kurashimo Eiji , Hirata Naoshi , Sakai Shinichi , Iwasaki Takaya , Kanazawa Toshihiko
Published: April 2005

The velocity structure and accurate aftershock distributions of the 2004 mid‐Niigata prefecture earthquake are elucidated by inverting the arrival times from 716 aftershocks using double‐difference tomography. Fourteen temporal seismic stations were immediately deployed in and around the source region within 46 h of the occurrence of mainshock. The seismic velocities in a hanging wall are lower than those in a footwall, and the velocity contrast extends to a depth of approximately 10 km. The aftershocks associated with the mainshock are distributed around the clear boundary between the low and high velocity structures. It is interpreted that the mainshock fault plane of the mid‐Niigata prefecture earthquake was reactivated as a reverse fault since the crustal shortening initiated at 3.5 Ma. Crustal stretching or shortening along the Japan coastline has created complex structures such as low velocity zones, which can potentially control the seismic activities around the source region.
The role of intracellular Ca2+ in the regulation of proteinase‐activated receptor‐2 mediated nuclear factor kappa B signalling in keratinocytes
Authors: Macfarlane Scott R , Sloss Callum M , Cameron Pamela , Kanke Toru , McKenzie Roderick C , Plevin Robin
Published: April 2005

In this study, we examined the role of Ca2+ in linking proteinase‐activated receptor‐2 (PAR2) to the nuclear factor kappa B (NFκB) pathway in a skin epithelial cell line NCTC2544 stably expressing PAR2 (clone G).

In clone G, PAR2‐mediated NFκB luciferase reporter activity and NFκB DNA‐binding activity was reduced by preincubation with BAPTA‐AM but not BAPTA. Trypsin stimulation of inhibitory kappa B kinases, IKKα and IKKβ, was also inhibited following pretreatment with BAPTA‐AM.

BAPTA/AM also prevented PAR2‐mediated IKKα activation in cultured primary human keratinocytes.

The effect of BAPTA‐AM was also selective for the IKK/NFκB signalling axis; PAR2 coupling to ERK, or p38 MAP kinase was unaffected.

Pharmacological inhibition of the Ca2+‐dependent regulatory protein calcineurin did not inhibit trypsin‐stimulated IKK activity or NFκB‐DNA binding; however, inhibition of Ca2+‐dependent protein kinase C isoforms or InsP3 formation using GF109203X or the phospholipase C inhibitor U73122, respectively, reduced both IKK activity and NFκB‐DNA binding.

Mutation of PAR2 within the C‐terminal to produce a mutant receptor, which does not couple to Ca2+ signalling, but is able to activate ERK, abrogated NFκB‐DNA binding and IKK activity stimulated by trypsin.

These results suggest a predominant role for the InsP3/Ca2+ axis in the regulation of IKK signalling and NFκB transcriptional activation.

British Journal of Pharmacology (2005) 145, 535–544. doi:10.1038/sj.bjp.0706204
Effects of bisindolylmaleimide PKC inhibitors on p90RSK activity in vitro and in adult ventricular myocytes
Authors: Roberts Neil A , Haworth Robert S , Avkiran Metin
Published: April 2005

Bisindolylmaleimide inhibitors of protein kinase C (PKC), such as GF109203X and Ro31‐8220, have been used to investigate the roles of PKC isoforms in many cellular processes in cardiac myocytes, but these agents may also inhibit p90RSK activity.

In in vitro kinase assays utilising 50 μM [ATP], GF109203X and Ro31‐8220 inhibited p90RSK isoforms (IC50 values for inhibition of RSK1, RSK2 and RSK3, respectively, were 610, 310 and 120 nM for GF109203X, and 200, 36 and 5 nM for Ro31‐8220) as well as classical and novel PKC isoforms (IC50 values for inhibition of PKCα and PKCɛ, respectively, were 8 and 12 nM for GF109203X, and 4 and 8 nM for Ro31‐8220).

At physiological [ATP] (5 mM), both GF109203X and Ro31‐8220 exhibited reduced potency as inhibitors of RSK2, PKCα and PKCɛ (IC50 values of 7400, 310 and 170 nM, respectively, for GF109203X, and 930, 150 and 140 nM, respectively, for Ro31‐8220), with the latter agent retaining its relatively greater potency.

To determine the effects of GF109203X and Ro31‐8220 on p90RSK activity in cultured adult rat ventricular myocytes (ARVM), phosphorylation of the eukaryotic elongation factor 2 kinase (eEF2K) at Ser366, a known p90RSK target, was used as the index of such activity. Adenoviral expression of a constitutively active form of mitogen‐activated protein kinase (MAPK) or extracellular signal‐regulated kinase (ERK) kinase 1 (MEK1) was used to induce PKC‐independent p90RSK activation and downstream phosphorylation of eEF2K.

eEF2K phosphorylation was abolished by U0126 (1 μM), a selective inhibitor of MEK1, and was significantly reduced by GF109203X at 3 μM and by Ro31‐8220 at 1 μM. At 1 μM, both agents inhibited PMA‐induced PKC activity in ARVM.

These data show that GF109203X and Ro31‐8220 inhibit various isoforms of PKC and p90RSK in vitro and in intact ARVM, with the former agent exhibiting relatively greater selectivity for PKC.

British Journal of Pharmacology (2005) 145, 477–489. doi:10.1038/sj.bjp.0706210
Prostaglandin E2‐induced modification of tetrodotoxin‐resistant Na+ currents involves activation of both EP2 and EP4 receptors in neonatal rat nodose ganglion neurones
Authors: Matsumoto Shigeji , Ikeda Mizuho , Yoshida Shinki , Tanimoto Takeshi , Takeda Mamoru , Nasu Masanori
Published: April 2005

The aim of the present study was to investigate which EP receptor subtypes (EP1–EP4) act predominantly on the modification of the tetrodotoxin‐resistant Na+ current (INaR) in acutely isolated neonatal rat nodose ganglion (NG) neurones.

Of the four EP receptor agonists ranging from 0.01 to 10 μM, the EP2 receptor agonist (ONO‐AE1‐259, 0.1–10 μM) and the EP4 receptor agonist (ONO‐AE1‐329, 1 μM) significantly increased peak INaR. The responses were associated with a hyperpolarizing shift in the activation curve.

Neither the EP1 receptor agonist ONO‐DI‐004 nor the EP3 receptor agonist ONO‐AE‐248 significantly modified the properties of INaR.

In PGE2 applications ranging from 0.01 to 10 μM, 1 μM PGE2 produced a maximal increase in the peak INaR amplitude. The PGE2 (1 μM)‐induced increase in the GV1/2 baseline (% change in G at baseline V1/2) was significantly attenuated by either intracellular application of the PKA inhibitor PKI or extracellular application of the protein kinase C inhibitor staurosporine (1 μM). However, the slope factor k was not significantly altered by PGE2 applications at 0.01–10 μM. In addition, the hyperpolarizing shift of V1/2 by PGE2 was not significantly altered by either PKI or staurosporine.

In other series of experiments, reverse transcription–polymerase chain reaction (RT–PCR) of mRNA from nodose ganglia indicated that all four EP receptors were present.

The NG contained many neuronal cell bodies (diameter <30 μm) with intense or moderate EP2, EP3, and EP4 receptor‐immunoreactivities.

These results suggest that the PGE2‐induced modification of INaR is mainly mediated by activation of both EP2 and EP4 receptors.

British Journal of Pharmacology (2005) 145, 503–513. doi:10.1038/sj.bjp.0706212
Sequence characterized amplified region markers for the rice blast fungus, Magnaporthe grisea
Authors: Soubabere O. , Jorge V. , Notteghem J. L. , Lebrun M. H. , Tharreau D.
Published: April 2005

We developed sequence characterized amplified region (SCAR) markers to monitor recombination and migration within Magnaporthe grisea populations. Twenty‐two primer pairs were designed from random amplified polymorphic DNA (RAPD) markers or available gene sequences. Sixteen of these SCARs were polymorphic in M. grisea when tested on 232 isolates collected from worldwide origins.
Isolation of nine novel tetranucleotide microsatellites in Atlantic herring (Clupea harengus)
Authors: McPherson A. A. , O'Reilly P. T. , McParland T. L. , Jones M. W. , Bentzen P.
Published: April 2005

Nine tetranucleotide microsatellite loci developed for Atlantic herring are presented. Loci were isolated using a magnetic bead hybridization selection protocol that yielded an 80% enrichment for tetranucleotide microsatellites. Fifty Atlantic herring from each of a North‐west and North‐east Atlantic spawning group were screened at each locus. Loci were polymorphic (12–56 alleles per locus) and exhibited high levels of observed heterozygosity (0.66–0.98). These loci are therefore suitable for population studies and the analysis of mating systems.
Isolation and characterization of microsatellite loci in black grouse (Tetrao tetrix)
Authors: Caizergues Alain , Dubois Sophie , Loiseau Anne , Mondor Guenaelle , Rasplus Jean‐Yves
Published: April 2005

We isolated eight microsatellite loci in the black grouse (Tetraonidae). Polymorphism ranged from 2 to 15 alleles (48 individuals from the same locality examined). Cross‐specific amplifications suggests that some of these microsatellites may be used in other tetraonids and, to a lesser extent, in some other phylogenetically more distant galliforms.
Isolation of microsatellite markers in the hermaphroditic land snail Arianta arbustorum (Gastropoda)
Authors: Locher R. , Baur B.
Published: April 2005

Five novel polymorphic microsatellite loci are presented for the simultaneously hermaphroditic land snail Arianta arbustorum. The isolation protocol was adapted from Estoup & Turgeon (see below). Because wild multiple mating with different partners has been observed in this gastropod, the microsatellite loci presented will be an efficient tool for paternity analysis.
Characterization of polymorphic microsatellite loci from the two endemic genera of Madagascan Boids, Acrantophis and Sanzinia
Authors: Matson Cole W. , Williamson Janet E. , Huebinger Ryan M. , Louis Edward E.
Published: April 2005

There are three Boid species endemic to Madagascar, which represent two genera (Acrantophis, Sanzinia). We have characterized 10 microsatellite loci that are polymorphic in all three species. These markers will provide a system to study population segregation, population diversity, gene flow, and many other parameters. This data will be useful in planning and implementing conservation plans for all three of these endangered Boid species.
Polymorphic microsatellites for the study of adults, egg‐masses and hatchlings of five Cerithium species (Gastropoda) from the Mediterranean sea
Authors: Samadi S. , Lambourdière J. , Hébert P. , Boisselier‐Dubayle M. C.
Published: April 2005

The genus Cerithium is represented in the Mediterranean Sea by several common species that have either planktotrophic or nonplanktotrophic larvae. Planktotrophic taxa are expected to disperse more than nonplanktotrophic taxa. Larval development is thus supposed to affect population structure. A set of six microsatellites was characterized for five Mediterranean Cerithium species. Loci were generally highly polymorphic (up to 30 alleles per locus and observed heterozygosity up to 0.938). These markers were used to genotype adults but also egg‐masses and hatchlings. We now have the opportunity to precisely study the consequences of each stage of the life cycle on population structure.
Dinucleotide microsatellites isolated from the European flat oyster, Ostrea edulis
Authors: Sobolewska H. , Beaumont A. R. , Hamilton A.
Published: April 2005

Approximately 5000 clones from a partial genomic library of Ostrea edulis DNA were screened with (CA)15 and (GA)15 probes. Fifty‐six positive clones were sequenced, with 24 containing a microsatellite sequence. Primers were designed for 14 loci, and the five most reliably amplifying were developed further. Four of these showed high levels of variability and only one locus (HA21) showed a significant deviation from Hardy–Weinberg expectations, with an excess of homozygotes. These microsatellite DNA markers will be powerful tools for the study of wild and hatchery stocks of this commercially important species.
Microsatellite loci in Gymnadenia conopsea, the fragrant orchid
Authors: Gustafsson Susanne , Thorén Peter A.
Published: April 2005

Six polymorphic microsatellite loci were found in two genomic libraries (one unenriched and one enriched) constructed using DNA originating from the fragrant orchid, Gymnadenia conopsea. These six microsatellite loci (Gc 17, 29, 42, 49, 51 and 77) showed high levels of variation (HO= 0.65, 0.90, 0.85, 0.75, 0.90 and 0.40, respectively) when 20 individuals from one population of G. conopsea were PCR amplified and separated in 6% PAA gels.
geneloss: a computer program for simulating the effects of population bottlenecks on genetic diversity
Authors: England P. R. , Osler G. H. R.
Published: April 2005

In the absence of tractable theory for predicting how population bottlenecks of longer than one generation reduce allelic diversity, we wrote the program geneloss to simulate the effects of population bottlenecks on genetic variation at highly polymorphic loci such as microsatellites. geneloss describes the heterozygosity and allelic diversity remaining after each iteration and averages the results of up to 3000 iterations. Thirty loci with 30 alleles each can be specified. Bottlenecks of up to 1000 pairs can run for an unlimited number of generations. geneloss will be a useful tool for the study of bottleneck effects and conservation biology.
Characterization of microsatellite loci in the stone loach, Barbatula barbatula L.
Authors: Taylor Martin I. , Blust Ronny , Verheyen Erik
Published: April 2005

We report the isolation and characterization of five polymorphic microsatellite loci in the stone loach, Barbatula barbatula (synonyms: Nemacheilus barbatularus, Noemacheilus barbatularus, Orthrias barbatularus), which is widely distributed over Europe excluding most parts of Scandinavia, Italy, Spain, and Scotland, and is threatened in Flanders, Belgium. Two loci are perfect dinucleotide repeats (Bbar4 and Bbar8), two loci are imperfect dinucleotide repeats (Bbar3 and Bbar7) and one locus is a dinucleotide compound repeat (Bbar11). The number of alleles per locus in 19 individuals screened range from five in Bbar3 to 15 in Bbar8.
A set of highly polymorphic microsatellite markers developed for the eastern grey kangaroo (Macropus giganteus)
Authors: Zenger K. R. , Cooper D. W.
Published: April 2005

The eastern grey kangaroo (Macropus giganteus) has increased in numbers leading to over‐abundant populations in areas of eastern Australia. We have developed nine highly polymorphic microsatellite loci to investigate their population structure and mating systems to manage this species more effectively. These loci show high levels of allelic diversity with the numbers of alleles ranging from 8 to 19 and with observed heterozygosities of 0.750–0.958. Null alleles or allelic dropouts were not detected when comparing animals of known pedigree.
Isolation and variability of polymorphic microsatellite loci in Aedes aegypti, the vector of dengue viruses
Authors: Huber K. , Mousson L. , Rodhain F. , Failloux A.‐B.
Published: April 2005

We isolated five microsatellite sequences from an enriched‐(CAA)n library of 5000 recombinant clones in Aedes aegypti. Two polymorphic microsatellites from our library and four from other sequence databases were tested: we investigated their polymorphism and Mendelian inheritance in mosquito populations. Our results indicate that trinucleotide repeat markers could be used to differentiate Ae. aegypti populations, making them valuable tools for the study of population genetic structure.
Single‐cell sequencing of dinoflagellate (Dinophyceae) nuclear ribosomal genes
Authors: Ruiz Sebastián C. , O’Ryan C.
Published: April 2005

Genetic sequences from dinoflagellates offer valuable information regarding taxonomies, phylogenies and population genetics that generally require the growth of these organisms in culture. We have developed a quick and simple method to obtain small and large subunit ribosomal gene sequences from dinoflagellates using single cells. This method, based on freeze–thaw cell lysis and a simple two‐step polymerase chain reaction, provides template for sequencing in 6–8 h. We have sequenced five dinoflagellate species, including unculturable Dinophysis and Ceratium species, using fresh and frozen samples.
A new primer set for sex identification in the genus Sorex (Soricidae, Insectivora)
Authors: Matsubara K. , Ishibashi Y. , Ohdachi S. , Matsuda Y.
Published: April 2005

In order to develop a new accurate method for sexing in Sorex species (Soricidae, Insectivora), we synthesized a polymerase chain reaction (PCR) primer set to amplify a part of Sry HMG box in the long‐clawed shrew, Sorex unguiculatus. When the primers were applied to the samples of known sex, PCR products were successfully obtained for males as a clear, single band on 3% agarose gels after electrophoresis in Sorex unguiculatus and five other Sorex species, but not for females of these six species. Thus, PCR amplification using the primer set may be applicable to discern sex in the six Sorex species.
Characterization of microsatellite loci in village indigobirds Vidua chalybeata and cross‐species amplification in estrildid and ploceid finches
Authors: Sefc K. M. , Payne R. B. , Sorenson M. D.
Published: April 2005

We characterized 11 microsatellite primer pairs for the village indigobird Vidua chalybeata. The loci were highly polymorphic, with 7–13 alleles per locus. Gene diversity, estimated as expected heterozygosity, ranged from 0.52 to 0.86, and was generally matched by levels of observed heterozygosity (0.49–0.91). Many of these primer pairs amplified polymorphic loci in cross‐species amplification trials with a variety of estrildid and ploceid finches and a sparrow, Passer griseus. These primers will be valuable for genetic analyses of the brood parasitic indigobirds and whydahs (genus Vidua) as well as other Old World finches.
Polymorphic microsatellite markers in the spider Pholcus phalangioides isolated from a library enriched for CA repeats
Authors: Rütten K. B. , Schulz I. , Olek K. , Uhl G.
Published: April 2005

Unravelling the factors that determine mating success in natural populations is highly important to the understanding of evolution of mating systems. To this aim, microsatellite loci were isolated and characterized from Pholcus phalangioides, a cosmopolitan spider. We modified a highly efficient enrichment procedure (Fischer & Bachman see below) which has several advantages compared to conventional methods. Fourteen polymorphic microsatellite loci are presented. The number of alleles per locus in 11–27 individuals screened range from 3 to 11. These are the first microsatellite loci reported from a spider.
lea (likelihood‐based estimation of admixture): a program to estimate simultaneously admixture and time since the admixture event
Authors: Langella O. , Chikhi L. , Beaumont M.A.
Published: April 2005

We consider an admixture event, T generations in the past, where two ‘parental’ populations, P1 and P2, of size N1 and N2, contribute different proportions into the gene pool of an admixed population, H of size Nh. lea (likelihood‐based estimator of admixture) is a program which allows the user to obtain the posterior distribution of the parameters of the model. This includes p1, the contribution of P1, and t1, t2 and th, the time since the admixture event (scaled by the population size) for the three populations. lea allows the user to stop and restart the analyses at any time.
Characterization of microsatellites in the fungal plant pathogen, Sclerotinia sclerotiorum
Authors: Sirjusingh Caroline , Kohn Linda M.
Published: April 2005

Twenty‐five primers produced unambiguous amplification products of 23 microsatellite‐containing loci and two microsatellite‐like polymorphic loci, with 2–10 alleles at each locus in the plant pathogenic fungus, Sclerotinia sclerotiorum. Haplotypes are polymorphic among individuals sharing the same DNA fingerprint and DNA sequence haplotype, facilitating epidemiological monitoring worldwide. Fourteen of these primers also successfully amplified the closely related S. trifoliorum and S. minor.
Isolation and characterization of microsatellite loci in the marine gastropod Nucella lapillus
Authors: Kawai K. , Hughes R. N. , Takenaka O.
Published: April 2005

Our paper deals the cloning and characterization of microsatellites from Nucella lapillus, and tests cross‐species amplification in a congener and in two species of the confamilial genus Thais. Fourteen of 31 microsatellite loci tested were polymorphic, with 4–9 (mean 5.93) alleles per locus. The observed heterozygosity per locus varied from 0.10 to 0.85 (mean 0.37) and expected heterozygosity from 0.48 to 0.85 (mean 0.65). Most primer pairs were successfully amplified in N. freycineti, although only one primer pair was successfully amplified in both species of Thais. The markers are potentially useful for other species of Nucella.
Isolation of microsatellite loci from spotted gum (Corymbia variegata), and cross‐species amplification in Corymbia and Eucalyptus
Authors: Jones M. E. , Stokoe R. L. , Cross M. J. , Scott L. J. , Maguire T. L. , Shepherd M.
Published: April 2005

Corymbia variegata (spotted gum) is an important commercial hardwood timber species in Australia. Fourteen polymorphic microsatellite loci were isolated from C. variegata, with 3–5 alleles amplified in three individuals examined. Cross‐species amplification in Corymbia was successful for all primer pairs, while 10 loci (71%) were successfully transferred to at least one species in the closely related genus Eucalyptus.
Trinucleotide microsatellite loci for the zebra mussel Dreissena polymorpha, an invasive species in Europe and North America
Authors: Naish Kerry A. , Boulding Elizabeth G.
Published: April 2005

The high mutation rate at microsatellite loci can supply important demographic information on founder events and range expansion in an invasive species such as the zebra mussel Dreissena polymorpha, following its initial introduction. In order to facilitate studies into the colonization patterns of this species in new habitats in Europe and North America, five trinucleotide microsatellite loci were isolated from a partial DNA library. Allelic diversity at all described loci was high, ranging from 20 to 35 alleles per locus. Homologous loci were not amplified in a second related invasive species, Dreisenna bugensis, using the primers developed here.
Isolation and characterization of trinucleotide microsatellites in African malaria mosquito Anopheles funestus
Authors: Sharakhov Igor V. , Braginets Olga , Mbogo Charles N. , Yan Guiyun
Published: April 2005

We developed microsatellite markers for an important African malaria mosquito Anopheles funestus Giles. The microsatellite‐enriched genomic library was constructed and screened with single‐strand oligonucleotides [(CCT)17, (AAT)17, (CAG)17 and (GA)25] as probes. Among the 47 pairs of polymerase chain reaction primers screened, 31 produced successful and consistent amplification. Although only a few A. funestus individuals from one geographical location were used to screen microsatellite marker polymorphism, 27 markers were found polymorphic and four markers monomorphic. Most polymorphic markers are trinucleotide markers. Isolation of polymorphic microsatellite markers provide useful tools for A. funestus population genetic studies and genome mapping.
Genetic variation in two populations of the rough‐skinned newt (Taricha granulosa) assessed using novel tetranucleotide microsatellite loci
Authors: Jones Adam G. , Blouin Michael S. , Arnold Stevan J.
Published: April 2005

Seven novel tetranucleotide microsatellite loci were identified from a partial genomic DNA library, enriched for GATA‐motif microsatellites, from the rough‐skinned newt (Taricha granulosa). All loci were polymorphic, and one displayed a high frequency null allele. A related species, T. rivularis, displays strong site fidelity and detectable population structure over small spatial scales, so we assessed genetic variation in two samples of T. granulosa separated by 16 km. Distributions of allele frequencies differ significantly between our two sites, but small values of FST and RhoST suggest that the populations are linked by a large amount of gene flow.
Isolation and characterization of polymorphic simple sequence repeat loci in Armillaria ostoyae
Authors: Langrell S. R. H. , Lung‐Escarmant B. , Decroocq S.
Published: April 2005

A modified hybridization strategy was used to construct a microsatellite enriched library from DNA of Armillaria ostoyae, a serious root pathogen on pine. Sequence characterization of 19 random clones revealed 12 distinct loci harbouring a repetitive motif. Primer design from the flanking regions allowed for their development as polymerase chain reaction based markers. Polymorphic assessment at both the population and global levels revealed levels of variation useful for genetic studies. The level of cross‐species amplification observed with closely related Armillaria species was high, raising the possible exploitation of these primers across the genus.
Development of microsatellite loci in pinto abalone (Haliotis kamtschatkana)
Authors: Miller K. M. , Laberee K. , Kaukinen K. H. , Li S. , Withler R. E.
Published: April 2005

Twelve novel di‐, tri‐ and tetranucleotide microsatellite loci to the pinto abalone (Haliotis kamtschatkana) are described. Over 400 individuals were analysed at each microsatellite locus. Observed heterozygosities ranged from 0.44 to 0.93, and numbers of alleles from 20 to 63. Six of the loci contained excesses in homozygosity indicative of inbreeding, nonrandom mating, population admixture, or null alleles.
Brassinosteroid‐Promoted Growth
Authors: Müssig C.
Published: April 2005

Abstract: Brassinosteroids (BRs) are highly potent growth‐promoting sterol derivatives. BR‐deficient or BR‐insensitive mutants display dwarfism. Whole plants and excised tissues have been used to analyse the mechanisms involved in BR‐promoted growth. BR stimulates cell elongation and cell division, and BR has specific effects on differentiation. Underlying physiological pathways include modification of cell wall properties, effects on carbohydrate assimilation and allocation, and control of aquaporin activities. BR apparently coordinates and integrates diverse processes required for growth, partly via interactions with other phytohormones setting the frame for BR responses. Ultimately, BR‐promoted growth is mediated through genomic pathways. Positive regulators of the BR response (such as BZR1 and BES1) and putative downstream components (such as EXO) are involved in the regulation of BR‐responsive genes and growth promotion. BR‐responsive genes have been identified in several plant species. However, causal links between physiological effects and changes of transcript patterns, for the most part, are still unresolved. This review focuses on physiology and molecular mechanisms underlying BR‐promoted growth in the different plant organs. Interactions with other phytohormones are discussed.
Heritable Variation in Seed Sex Ratio of the Stinging Nettle (Urtica dioica)
Authors: de Jong T. J. , Nell H. W. , Glawe G. A.
Published: April 2005

Abstract: Male and female flowering plants of the dioecious Urtica dioica occur in approximately equal numbers in our study area on the coastal sand dunes of Meijendel. The seed sex ratio (SSR, fraction of males) collected from female plants in the field varied between 0.05 and 0.76, and differed significantly between maternal parents. After one generation of selection for either high or low SSR, female plants produced seed batches with sex ratios as extreme as 0.08 and 0.73. Natural populations of U. dioica harbour considerable genetic variation in SSR.
Sexual Dimorphism and Gynoecium Size Variation in the Andromonoecious Shrub Caesalpinia gilliesii
Authors: Calviño A. , Carrizo García C.
Published: April 2005

Abstract: The degree of sexual dimorphism in flowers and inflorescences can be evaluated early in flower development through the study of floral organ size co‐variation. In the present work, the gynoecium‐androecium size relationship was studied to assess the degree of sexual expression in flowers and inflorescences of the andromonoecious shrub Caesalpinia gilliesii. The co‐variation pattern of floral organ sizes was compared between small and large inflorescences, under the hypothesis that inflorescence size reflected differential resource availability. Also, staminate and perfect flowers were collected from three populations and compared on the basis of gynoecium, ovule length, filament length, pollen size and number. The obtained results indicated that staminate and perfect flowers differed only in the gynoecium and ovule length, whereas filament length, pollen size, and number varied across populations. The gynoecium size was smaller and its variability was much higher in staminate than in perfect flowers, as explained by a recent hypothesis about pollinator‐mediated gynoecium size selection acting upon perfect flowers. The analysis of the gynoecium‐androecium size relationship during flower development, revealed a dissociation of gynoecium growth relative to other floral structures in some buds. Lower gynoecium‐androecium regression slopes and smaller gynoecia length characterized smaller inflorescences, thus reflecting the fact that sexual expression was more male‐biased. This trend is in agreement with a differential resource‐related response at the inflorescence level, however, post‐mating resource allocation and the inclusion of other modular levels may also help us to understand the variation in sexual dimorphism in this species.
The Distribution of Membrane‐Bound 14‐3‐3 Proteins in Organelle‐Enriched Fractions of Germinating Lily Pollen
Authors: Pertl H. , Gehwolf R. , Obermeyer G.
Published: April 2005

Abstract: Proteins of the 14‐3‐3 family show a broad range of activities in plants, depending on their localisation in different cellular compartments. Different organelle membranes of pollen grains and pollen tubes of Lilium longiflorum Thunb. were separated simultaneously using optimised discontinuous sucrose density centrifugation. The obtained organelle‐enriched fractions were identified as vacuolar, Golgi, endoplasmic reticulum and plasma membranes, according to their marker enzyme activities, and were assayed for membrane‐bound 14‐3‐3 proteins by immunodetection. 14‐3‐3 proteins were detected in the cytoplasm as well as in all obtained organelle fractions but were also released into the extracellular medium. In pollen grains, much more plasma membrane‐bound 14‐3‐3 proteins were detected than in the PM‐enriched fraction of pollen tubes, whereas the level of Golgi‐ and ER‐associated 14‐3‐3 proteins was similar in pollen grains and tubes. This shift in the localisation of membrane‐associated 14‐3‐3 proteins is probably correlated with a change in the major function of 14‐3‐3 proteins, e.g., perhaps changing from initiating pollen grain germination by activation of the PM H+‐ATPase to recruitment of membrane proteins via the secretory pathway during tube elongation.
A theoretical study on anomalous temperature dependence of pKw of water
Authors: Yagasaki Takuma , Iwahashi Kensuke , Saito Shinji , Ohmine Iwao
Published: April 2005

p H , with its well-known value of 7 at ambient condition, is a most basic property of water, with wide implications in chemistry and biology. The pH value is determined by the tendency of autoionization of water molecules into ion pairs, H+ and OH−, and is expected to vary extensively with the water condition, which determines the stability of the ion pairs. When temperature rises from the normal to the supercritical region, the pH of water experimentally exhibits complex, nonmonotonic temperature dependence, that is, it first decreases from 7 and then increases rapidly. Accurate theoretical evaluation of pH and microscopic understanding of this anomalous behavior have proven to be a challenging task because the hydration of these ions, especially for OH−, is very difficult to reproduce. In the present study a molecular simulation is performed to understand this peculiar temperature dependence. The imbalance between the ion-water and the water-water molecular interaction strengths and the concomitant water density enhancement in the hydration shell, observed in the supercritical liquids, serve to put a subtle balance to produce this temperature dependence of the pH value. It is found that the large charge transfers from H+ and OH− to the surrounding water molecules take place. In these transfers, not only water molecules in the neighboring hydration shell but also those in the outer hydration shell play a significant role. The coordination number of water molecules around OH− is found to be 4.5 at 300K, which decreases slowly with temperature, for example, 4 at 800K, in the present calculation.
Experimental detection and theoretical characterization of the H2–NH(X) van der Waals complex
Authors: Fawzy Wafaa M. , Kerenskaya Galina , Heaven Michael C.
Published: April 2005

The H2–NH(X) van der Waals complex has been examined using ab initio theory and detected via fluorescence excitation spectroscopy of the A3Π−X3Σ− transition. Electronic structure calculations show that the minimum energy geometry corresponds to collinear H2–NH(X), with a well depth of De=116cm−1. The potential-energy surface supports a secondary minimum for a T-shaped geometry, where the H atom of NH points towards the middle of the H2 bond (C2v point group). For this geometry the well depth is 73cm−1. The laser excitation spectra for the complex show transitions to the H2+NH(A) dissociative continuum. The onset of the continuum establishes a binding energy of D0=32±2cm−1 for H2–NH(X). The fluorescence from bound levels of H2–NH(A) was not detected, most probably due to the rapid reactive decay [H2–NH(A)→H+NH2]. The complex appears to be a promising candidate for studies of the photoinitiated H2+NH abstraction reaction under conditions were the reactants are prealigned by the van der Waals forces.
Configurational invariants of Hamiltonian systems
Authors: Pucacco Giuseppe , Rosquist Kjell
Published: April 2005

In this paper we explore the general conditions in order that a two-dimensional natural Hamiltonian system possess a second invariant which is a polynomial in the momenta and is therefore Liouville integrable. We examine the possibility that the invariant is preserved by the Hamiltonian flow on a given energy hypersurface only (weak integrability) and derive the additional requirement necessary to have conservation at arbitrary energy (strong integrability). Using null complex coordinates, we show that the leading order coefficient of the polynomial is an arbitrary holomorphic function in the case of weak integrability and a polynomial in the coordinates in the strongly integrable one. We review the results obtained so far with strong invariants up to degree four and provide some new examples of weakly integrable systems with linear and quadratic invariants.
GaN-based anion selective sensor: Probing the origin of the induced electrochemical potential
Authors: Chaniotakis Nikos A. , Alifragis Yiannis , Georgakilas Alexandros , Konstantinidis Giorgos
Published: April 2005

The gallium nitride (GaN) semiconductor has been used as the sensing element in a chemical sensor for the measurement of charged species in solution. The sensor shows remarkable selectivity for anions, such as sulphate (SO42−) and hydroxide (OH−). It is shown that the GaN surface interacts selectively with Lewis bases as shown by impedance spectra. In addition, both the impedance spectra and the surface induced potential of the sensor element correlate very well with the activity of both the negatively charged hydroxide and the sulphate anions used. These results indicate that there is a direct interaction of the electron deficient gallium in the GaN surface with the Lewis base anionic ligands. A band model for the investigated GaN∕KOH-solution system has been deduced.
Nanoindentation study of the superlattice hardening effect at TiC(110)/NbC(110) interfaces
Authors: Sekkal W. , Zaoui A. , Schmauder S.
Published: April 2005

We present an atomistic calculation using the embedded atom method in order to investigate nanoindentation in superlattices based on carbide materials. The purpose is to conduct a nanoindentation simulation study in order to evaluate the hardness of TiC and the one of TiC∕NbC. Results clearly show that this calculated quantity increases considerably from the carbide alone to the carbide in sandwich with another one like NbC. This mainly highlights the possibility to increase the hardness of carbide materials and confirms theoretically the previous experimental deductions.
THz Sommerfeld wave propagation on a single metal wire
Authors: Jeon Tae-In , Zhang Jiangquan , Grischkowsky D.
Published: April 2005

We report an experimental and theoretical study of THz Sommerfeld wave propagation on a single copper wire. THz pulses are optoelectronically generated and launched onto 0.52-mm-diam copper wire, and the guided THz pulses are detected at the end of the wire by a standard photoconductive antenna. Very low attenuation and group velocity dispersion are observed, and the measured radial field amplitude of the Sommerfeld wave is inversely proportional to the radial distance. These results are consistent with theoretical predictions. Experimental results from curved wires show the weakly guiding property of the THz Sommerfeld wave, which will limit its applications.
Cantilever calibration for nanofriction experiments with atomic force microscope
Authors: Morel N. , Ramonda M. , Tordjeman Ph.
Published: April 2005

The lateral force microscope can provide information on frictional properties on surfaces down to the nanometer scale. Reproducible quantitative measurements require an accurate calibration of the mechanical response of cantilever. In this letter, we propose a fast and nondestructive method to determine the normal and lateral cantilever stiffness, kcantileverN and kcantileverL, used to calculate the normal and friction forces.
Laminin–sulfatide binding initiates basement membrane assembly and enables receptor signaling in Schwann cells and fibroblasts
Authors: Li Shaohua , Liquari Patricia , McKee Karen K. , Harrison David , Patel Raj , Lee Sean , Yurchenco Peter D.
Published: April 2005

Endoneurial laminins (Lms), β1-integrins, and dystroglycan (DG) are important for Schwann cell (SC) ensheathment and myelination of axons. We now show that SC expression of galactosyl-sulfatide, a Lm-binding glycolipid, precedes that of Lms in developing nerves. This glycolipid anchors Lm-1 and -2 to SC surfaces by binding to their LG domains and enables basement membrane (BM) assembly. Revealingly, non–BM-forming fibroblasts become competent for BM assembly when sulfatides are intercalated into their cell surfaces. Assembly is characterized by coalescence of sulfatide, DG, and c-Src into a Lm-associated complex; by DG-dependent recruitment of utrophin and Src activation; and by integrin-dependent focal adhesion kinase phosphorylation. Collectively, our findings suggest that sulfated glycolipids are key Lm anchors that determine which cell surfaces can assemble Lms to initiate BM assembly and DG- and integrin-mediated signaling.