bluuebunny/crossref_metadata_2025 huggingface dataset:
Single-Pixel Optical Fluctuation Analysis of Calcium Channel Function in Active Zones of Motor Nerve Terminals
Authors: Luo Fujun , Dittrich Markus , Stiles Joel R. , Meriney Stephen D.
Published: August 2011

We used high-resolution fluorescence imaging and single-pixel optical fluctuation analysis to estimate the opening probability of individual voltage-gated calcium (Ca2+) channels during an action potential and the number of such Ca2+channels within active zones of frog neuromuscular junctions. Analysis revealed ∼36 Ca2+channels within each active zone, similar to the number of docked synaptic vesicles but far less than the total number of transmembrane particles reported based on freeze-fracture analysis (∼200–250). The probability that each channel opened during an action potential was only ∼0.2. These results suggest why each active zone averages only one quantal release event during every other action potential, despite a substantial number of docked vesicles. With sparse Ca2+channels and low opening probability, triggering of fusion for each vesicle is primarily controlled by Ca2+influx through individual Ca2+channels. In contrast, the entire synapse is highly reliable because it contains hundreds of active zones.
Operant Conditioning of Rat Soleus H-Reflex Oppositely Affects Another H-Reflex and Changes Locomotor Kinematics
Authors: Chen Yi , Chen Lu , Wang Yu , Wolpaw Jonathan R. , Chen Xiang Yang
Published: August 2011

H-reflex conditioning is a model for studying the plasticity associated with a new motor skill. We are exploring its effects on other reflexes and on locomotion. Rats were implanted with EMG electrodes in both solei (SOLRand SOLL) and right quadriceps (QDR), and stimulating cuffs on both posterior tibial (PT) nerves and right posterior femoral nerve. When SOLREMG remained in a defined range, PTRstimulation just above M-response threshold elicited the SOLRH-reflex. Analogous procedures elicited the QDRand SOLLH-reflexes. After a control period, each rat was exposed for 50 d to a protocol that rewarded SOLRH-reflexes that were above (HRup rats) or below (HRdown rats) a criterion. HRup conditioning increased the SOLRH-reflex to 214 ± 37% (mean ± SEM) of control (p= 0.02) and decreased the QDRH-reflex to 71 ± 26% (p= 0.06). HRdown conditioning decreased the SOLRH-reflex to 69 ± 2% (p< 0.001) and increased the QDRH-reflex to 121 ± 7% (p= 0.02). These changes remained during locomotion. The SOLLH-reflex did not change. During the stance phase of locomotion, ankle plantarflexion increased in HRup rats and decreased in HRdown rats, hip extension did the opposite, and hip height did not change. The plasticity that changes the QDRH-reflex and locomotor kinematics may be inevitable (i.e., reactive) due to the ubiquity of activity-dependent CNS plasticity, and/or necessary (i.e., compensatory) to preserve other behaviors (e.g., locomotion) that would otherwise be disturbed by the change in the SOLRH-reflex pathway. The changes in joint angles, coupled with the preservation of hip height, suggest that compensatory plasticity did occur.
Experience-Dependent Plasticity Acts via GluR1 and a Novel Neuronal Nitric Oxide Synthase-Dependent Synaptic Mechanism in Adult Cortex
Authors: Dachtler James , Hardingham Neil R. , Glazewski Stanislaw , Wright Nicholas F. , Blain Emma J. , Fox Kevin
Published: August 2011

Synaptic plasticity directs development of the nervous system and is thought to underlie memory storage in adult animals. A great deal of our current understanding of the role of AMPA receptors in synaptic plasticity comes from studies on developing cortex and cell cultures. In the present study, we instead focus on plasticity in mature neurons in the neocortex of adult animals. We find that the glutamate receptor 1 (GluR1) subunit of the AMPA receptor is involved in experience-dependent plasticity in adult cortexin vivoand that it acts in addition to neuronal nitric oxide synthase (αNOS1), an enzyme that produces the rapid synaptic signaling molecule nitric oxide (NO). Potentiation of the spared whisker response, following single whisker experience, is ∼33% less in GluR1-null mutants than in wild types. We found that the remaining plasticity depended on αNOS1. Potentiation was reduced by >42% in the single αNOS1-null mutants and completely abolished in GluR1/αNOS1 double-knock-out mice. However, potentiation in GluR1/NOS3 double knock-outs occurred at similar levels to that seen in GluR1 single knock-outs. Synaptic plasticity in the layer IV to II/III pathwayin vitromirrored the resultsin vivo, in that LTP was present in GluR1/NOS3 double-knock-out mice but not in the GluR1/αNOS1 animals. While basal levels of NO in cortical slices depended on both αNOS1 and NOS3, NMDA receptor-dependent NO release only depended on αNOS1 and not on NOS3. These findings demonstrate that αNOS1 acts in concert with GluR1 to produce experience-dependent plasticity in the neocortex.
Identification of a Dopamine Receptor-Mediated Opiate Reward Memory Switch in the Basolateral Amygdala–Nucleus Accumbens Circuit
Authors: Lintas Alessandra , Chi Ning , Lauzon Nicole M. , Bishop Stephanie F. , Gholizadeh Shervin , Sun Ninglei , Tan Huibing , Laviolette Steven R.
Published: August 2011

The basolateral amygdala (BLA), ventral tegmental area (VTA), and nucleus accumbens (NAc) play central roles in the processing of opiate-related associative reward learning and memory. The BLA receives innervation from dopaminergic fibers originating in the VTA, and both dopamine (DA) D1 and D2 receptors are expressed in this region. Using a combination ofin vivosingle-unit extracellular recording in the NAc combined with behavioral pharmacology studies, we have identified a double dissociation in the functional roles of DA D1 versus D2 receptor transmission in the BLA, which depends on opiate exposure state; thus, in previously opiate-naive rats, blockade of intra-BLA D1, but not D2, receptor transmission blocked the acquisition of associative opiate reward memory, measured in an unbiased conditioned place preference procedure. In direct contrast, in rats made opiate dependent and conditioned in a state of withdrawal, intra-BLA D2, but not D1, receptor blockade blocked opiate reward encoding. This functional switch was dependent on cAMP signaling as comodulation of intra-BLA cAMP levels reversed or replicated the functional effects of intra-BLA D1 or D2 transmission during opiate reward processing. Single-unitin vivoextracellular recordings performed in neurons of the NAc confirmed an opiate-state-dependent role for BLA D1/D2 transmission in NAc neuronal response patterns to morphine. Our results characterize and identify a novel opiate addiction switching mechanism directly in the BLA that can control the processing of opiate reward information as a direct function of opiate exposure state via D1 or D2 receptor signaling substrates.
Pool-Specific Regulation of Motor Neuron Survival by Neurotrophic Support
Authors: Lamballe Fabienne , Genestine Matthieu , Caruso Nathalie , Arce Vilma , Richelme Sylvie , Helmbacher Françoise , Maina Flavio
Published: August 2011

The precise control of motor neuron (MN) death and survival following initial innervation of skeletal muscle targets is a key step in sculpting a functional motor system, but how this is regulated at the level of individual motor pools remains unclear. Hepatocyte growth factor (HGF) and its receptor Met play key developmental roles in both muscle and MNs. We generated mice (termed “Nes-Met”) in whichmetis inactivated from midembryonic stages onward in the CNS only. Adult animals showed motor behavioral defects suggestive of impaired innervation of pectoral muscles. Correspondingly, in neonatal spinal cords ofNes-Metmutants, we observed death of a discrete population ofpea3-expressing MNs at brachial levels. Axonal tracing usingpea3reporter mice revealed a novel target muscle ofpea3-expressing MNs: the pectoralis minor muscle. InNes-Metmice, the pectoralis minor pool initially innervated its target muscle, but required HGF/Met for survival, hence for proper maintenance of muscle innervation. In contrast, HGF/Met was dispensable for the survival of neighboring Met-expressing MN pools, despite its earlier functions for their specification and axon growth. Our results demonstrate the exquisite degree to which outcomes of signaling by receptor tyrosine kinases are regulated on a cell-by-cell basis. They also provide a model for one way in which the multiplicity of neurotrophic factors may allow for regulation of MN numbers in a pool-specific manner.
The Detection of Visual Contrast in the Behaving Mouse
Authors: Busse Laura , Ayaz Asli , Dhruv Neel T. , Katzner Steffen , Saleem Aman B. , Schölvinck Marieke L. , Zaharia Andrew D. , Carandini Matteo
Published: August 2011

The mouse is becoming a key species for research on the neural circuits of the early visual system. To relate such circuits to perception, one must measure visually guided behavior and ask how it depends on fundamental stimulus attributes such as visual contrast. Using operant conditioning, we trained mice to detect visual contrast in a two-alternative forced-choice task. After 3–4 weeks of training, mice performed hundreds of trials in each session. Numerous sessions yielded high-quality psychometric curves from which we inferred measures of contrast sensitivity. In multiple sessions, however, choices were influenced not only by contrast, but also by estimates of reward value and by irrelevant factors such as recent failures and rewards. This behavior was captured by a generalized linear model involving not only the visual responses to the current stimulus but also a bias term and history terms depending on the outcome of the previous trial. We compared the behavioral performance of the mice to predictions of a simple decoder applied to neural responses measured in primary visual cortex of awake mice during passive viewing. The decoder performed better than the animal, suggesting that mice might not use optimally the information contained in the activity of visual cortex.
Myocardial Infarction Registry – 2010. Feasibility and first results
Authors: Jánosi András , Ofner Péter , Merkely Béla , Polgár Péter , Andréka Péter , Zámolyi Károly , Kiss Róbert Gábor , Tomcsányi János , László Zoltán , Vértes András , Varjú Imre , Juhász Ferenc , Simon János , Bajkó Sándor
Published: August 2011

Authors present the methodology and first data of Hungarian Myocardial Infarction Register Pilot Study started 1st of January, 2010. The aim of the study is to collect epidemiological data on myocardial infarction, to examine the natural history of the disease and to investigate the main characteristics on patient care in the pilot area. The program is using standardized diagnostic criteria and predefined electronic data record forms (eCRF). The pilot area consists of 5 districts in the capital, and Szabolcs-Szatmár-Bereg county. The area has 997 324 inhabitants. Eight cardiology departments, 5 with heart catheterization facility (C) in Budapest, four hospitals with one C in Szabolcs-Szatmar-Bereg county have been responsible of the patients’ care. After starting the program 16 other hospitals joined the program from different parts of Hungary. Between 1st of January 2010 and 1st of May 2011 4293 patients were registered, among them 52.1% with ST segment elevation myocardial infarction (STEMI), 42.1% with non-ST segment elevation myocardial infarction (NSTEMI), while 3% of the patients had unstable angina, and 2.8% of the cases had other diagnosis or the hospital diagnosis was missing in the eCRF. Authors compare the patients care with STEMI in five districts of Budapest and Szabolcs-Szatmár-Bereg county. In Budapest 79.7% of the 301 STEMI patients were treated in C and 84.6% of them were treated with primary percutaneous intervention (pPCI). In Szabolcs-Szatmár-Bereg county 402 patients were registered with STEMI, 62.9% of them were treated in C, where 77% of them were treated with pPCI. The drugs (beta blockers, ACE inhibitors, statins) important for secondary prevention were given more often to patients treated in the capital, however no difference was found in the platelet aggregation inhibitors therapy. Hospital mortality of STEMI patients was 8% in the capital, and 10% in Szabolcs- Szatmár-Bereg county. Authors conclude that the web based myocardial infarction register is feasible and important to have reliable data on patient care and a necessary quality control tool. Authors propose to broaden this pilot program and to start a nationwide myocardial infarction register. Orv. Hetil., 2011, 152, 1278–1283.
Relating the maximum radial stress on pile shaft to pile base resistance
Authors: YANG J. , MU F.
Published: August 2011

An approximate analytic relationship is developed between the maximum radial stress on the shaft of a displacement pile in sand and the base resistance of the pile. Using the cavity expansion analogy, together with a confined failure mechanism, the ratio between the two quantities, defined as a factor St, is established as a function of the friction angle, shear stiffness, compressibility and mean effective stress of the sand near the pile tip. It is shown that, given otherwise identical input parameters, the value of St will decrease with increasing friction angle, and with decreasing mean stress level. It also tends to decrease with an increase in relative density. It is predicted that St has typical values between 0·03 and 0·05, in broad agreement with the range of empirically derived values in the literature. The relationship also predicts that St may take much higher values (∼0·1) for piles installed in dense sand or in highly compressible sand. Because of the analytical nature, the established relationship provides useful insights into the mechanisms involved and important implications for design practice.
Calibration of a thermal conductivity sensor for field measurement of matric suction
Authors: LEONG E.C. , ZHANG X.-H. , RAHARDJO H.
Published: August 2011

This paper examines the calibration of a thermal conductivity sensor used for in situ matric suction measurement. A new calibration method is introduced. Performance of the thermal conductivity sensor in terms of salinity of pore water, heating power, hysteresis, response time and matric suction measurement range is also examined.
Trends and causes of severity, size, and number of fires in northwestern California, USA
Authors: Miller J. D. , Skinner C. N. , Safford H. D. , Knapp E. E. , Ramirez C. M.
Published: August 2011

Research in the last several years has indicated that fire size and frequency are on the rise in western U.S. forests. Although fire size and frequency are important, they do not necessarily scale with ecosystem effects of fire, as different ecosystems have different ecological and evolutionary relationships with fire. Our study assessed trends and patterns in fire size and frequency from 1910 to 2008 (all fires > 40 ha), and the percentage of high‐severity in fires from 1987 to 2008 (all fires > 400 ha) on the four national forests of northwestern California. During 1910–2008, mean and maximum fire size and total annual area burned increased, but we found no temporal trend in the percentage of high‐severity fire during 1987–2008. The time series of severity data was strongly influenced by four years with region‐wide lightning events that burned huge areas at primarily low–moderate severity. Regional fire rotation reached a high of 974 years in 1984 and fell to 95 years by 2008. The percentage of high‐severity fire in conifer‐dominated forests was generally higher in areas dominated by smaller‐diameter trees than in areas with larger‐diameter trees. For Douglas‐fir forests, the percentage of high‐severity fire did not differ significantly between areas that re‐burned and areas that only burned once (10% vs. 9%) when re‐burned within 30 years. Percentage of high‐severity fire decreased to 5% when intervals between first and second fires were >30 years. In contrast, in both mixed‐conifer and fir/high‐elevation conifer forests, the percentage of high‐severity fire was less when re‐burned within 30 years compared to first‐time burned (12% vs. 16% for mixed conifer; 11% vs. 19% for fir/high‐elevation conifer). Additionally, the percentage of high‐severity fire did not differ whether the re‐burn interval was less than or greater than 30 years. Years with larger fires and greatest area burned were produced by region‐wide lightning events, and characterized by less winter and spring precipitation than years dominated by smaller human‐ignited fires. Overall percentage of high‐severity fire was generally less in years characterized by these region‐wide lightning events. Our results suggest that, under certain conditions, wildfires could be more extensively used to achieve ecological and management objectives in northwestern California.
Influence of Oleic Acid Content on Yield in Winter Oilseed Rape
Authors: Schierholt Antje , Becker Heiko C.
Published: August 2011

Winter oilseed rape (Brassica napus L.) with a high oleic (>75%) and/or low linolenic acid (∼2%) content in the seed oil is of interest for nutritional and technical purposes. We analyzed whether a change in seed fatty acid composition has a direct influence on yield. Parental lines with different fatty acid composition were crossed, the segregating F2 populations were divided, and F3 bulks with contrasting fatty acid profiles were tested in two experiments. In Experiment 1, we developed four bulks in each of three crosses, which varied in oleic (58 to 82%) and linolenic (2 to 11%) acid content. F3 bulks were tested for 2 yr at three locations in Germany. In Experiment 2, two F3 bulks each were developed in 16 segregating F2 populations with high (74 to 79%) and low (59 to 64%) oleic acid content. F3 bulks were tested for 1 yr at five locations. The seed linolenic acid content did not significantly affect yield. In both experiments high oleic acid content was negatively associated with yield (with a reduction of 1.7 deciton [dt] ha−1 and 2.0 dt ha−1 of high versus low oleic acid bulks in Experiments 1 and 2). High oleic bulks exhibited a significantly increased oil content (+0.6%). Yield was negatively correlated with leaf and seed oleic acid content (r = –0.52 and r = –0.48, respectively). Seeds with high oleic acid content showed a significantly retarded germination. Breeding high oleic varieties could be complicated by the negative correlation between yield and oleic acid content.
Seed Dormancy in Mexican Teosinte
Authors: Avendaño López Adriana Natividad , de Jesús Sánchez González José , Ruíz Corral José Ariel , De La Cruz Larios Lino , Santacruz‐Ruvalcaba Fernando , Sánchez Hernández Carla Vanessa , Holland James B.
Published: August 2011

Seed dormancy in wild Zea species may affect fitness and relate to ecological adaptation. The primary objective of this study was to characterize the variation in seed germination of the wild species of the genus Zea that currently grow in México and to relate this variation to their ecological zones of adaptation. In addition, we compared methods to break dormancy and measured the germination responses of seeds to environment factors that are related to seasonal changes. Teosinte populations representing all the taxonomic and racial groups known in México were collected during the period 2003 to 2008 in twelve states of México. Seed dormancy was classified according to the rate of its loss (depth of dormancy). Results indicated that more than 90% of populations studied had some degree of seed dormancy. Nondormant populations are distributed predominantly in semicold areas, while deep and very deep seed dormancy was found in populations distributed in hot and very hot environments in well defined geographic regions of the Balsas River Basin and in San Felipe Usila, Oaxaca. Mechanical seed scarification was the best method to break dormancy.
Transgenic Potato Overexpressing the Amaranthus caudatus Agglutinin Gene to Confer Aphid Resistance
Authors: Xin Yang , Xiangrong Zhang , Mingju Zhang , Wenchao Guo , Yingchuan Tian , Qizhong Xia , Jiahe Wu
Published: August 2011

Potato (Solanum tuberosum L.) was transformed with a pBCACAc vector harboring the Amaranthus caudatus agglutinin (ACA) gene mediated by Agrobacterium tumefaciens (Smith and Townsend 1907) Conn. One hundred and eighteen of a total 320 regenerated plants were confirmed to possess the ACA gene integrated into the potato genome as detected by polymerase chain reaction (PCR) and Southern blot analysis. Three transgenic events (referred to as PA1, PA2, and PA3) with one copy of the ACA gene insertion and no obvious phenotypic change were selected and further evaluated for expression level of ACA protein and performance in insect bioassays. Based on western blot assays, the content of ACA protein in PA1, PA2, and PA3 events was high at 0.11, 0.32, and 0.29%, respectively, of total soluble leaf protein. The propagation of peach‐potato aphids (Myzus persicae Sulzer) in the three events was significantly inhibited, with 49, 18.5, and 25 aphids per plant, respectively, compared to 102.5 aphids per plant in nontransformed (NT) controls based on insect bioassays in greenhouse trials. The results of a field trial (in Beijing in 2009) showed that the number of aphids was significantly lower in transgenic plants than in NT. Tuber weight and plant yield of the three transgenic events were significantly higher than those of NT. Our results indicated that PA2 and PA3 can be regarded as potential germplasm to breed new cultivars that may decrease production loss from resistance to aphids and reduced indirect virus damage.
Efficacy of qFL‐chr1, a Quantitative Trait Locus for Fiber Length in Cotton (Gossypium spp.)
Authors: Shen Xinlian , Cao Zhibin , Singh Rippy , Lubbers Edward L. , Xu Peng , Smith C. Wayne , Paterson Andrew H. , Chee Peng W.
Published: August 2011

In an earlier advanced‐backcross quantitative trait locus (QTL) analysis of an interspecific Gossypium hirsutum L. × Gossypium barbadense L. population, 28 fiber length QTLs were identified including qFL‐chr1 on chromosome 1 of the A‐subgenome. The G. barbadense allele at this QTL contributed to longer fibers and explained up to 24% of the phenotypic variance. To substantiate the association of this genomic region with fiber length, three BC3F2 plants heterozygous for the genetic markers that delineate the qFL‐chr1 QTL were selected to construct three independent populations of near‐isogenic introgression lines (NIILs). The efficacy of qFL‐chr1 was evaluated among 140 NIILs grown in 2 yr. The results support the positive effect of qFL‐chr1 on fiber length. A single NIIL, R01‐40‐08, had about 94.3% of recurrent genome composition and significantly longer fiber than the recurrent parent when grown in Nanjing, China. Therefore, in addition to confirming the efficacy of qFL‐chr1 to enhance fiber length, this work provides a valuable genetic resource for the improvement of cotton.
Relationships between Normalized Difference Vegetation Index and Visual Quality in Cool‐Season Turfgrass: I. Variation among Species and Cultivars
Authors: Bremer Dale J. , Lee Hyeonju , Su Kemin , Keeley Steven J.
Published: August 2011

Canopy spectral reflectance may provide an objective means to evaluate visual quality of turfgrass, but evaluations of visual quality may be confounded by differences in reflectance among species or cultivars. In this 3‐yr study near Manhattan, KS, we examined effects of species and cultivars on relationships between normalized difference vegetation index (NDVI) and visual quality ratings in Kentucky bluegrass (Poa pratensis L., ‘Apollo’), two Kentucky bluegrass × Texas bluegrass (Poa arachnifera Torr.) hybrids (‘Thermal Blue’ and ‘Reveille’), and tall fescue (Festuca arundinacea Schreb., ‘Dynasty’). A broad range of visual quality was imposed on all four grasses through deficit irrigation and NDVI was measured using broadband spectral radiometry across this range for each grass. Distinct linear regression models of visual quality were found for each grass, and models were also distinct among years in each grass. Relationships between NDVI and visual quality were stronger in the bluegrasses (r2 = 0.41 to 0.83) because they had a greater range in quality under deficit irrigation than tall fescue. The 95% confidence intervals surrounding predictions of visual quality from NDVI ranged from ± 1.25 to 2.10 (on a 1 to 9 scale). Results indicated that the requirement to develop separate models for each grass and in each year, combined with relatively wide confidence intervals, represents a practical limitation to predicting visual quality with NDVI.
The Relationship of Temperature to Plant Morphology of Lesquerella
Authors: Dierig David A. , Crafts‐Brandner Steven J.
Published: August 2011

There is a lack of information regarding the impact of temperature on yield‐related traits for lesquerella [Physaria fendleri (Gray)], a new crop with potential as a biofuel or bioproduct because of the high content of seed hydroxyl fatty acids. Here we determined the effect of four temperature regimes on plant branching, dry matter production, and reproductive growth in two controlled‐environment experiments. The night/day temperature treatments were (1) 4.4/12.8°C, (2) 12.8/21.1°C, (3) 21.1/29.4°C, and (4) 29.4/37.8°C. Plant branch number, biomass, and reproductive development were greatly suppressed by the coolest and warmest temperature treatments. Biomass and branch production were similar for Treatments 2 and 3, but reproductive development and was increased in Treatment 2. Treatment 2 led to more branches with reproductive structures and more buds and flowers than Treatment 3. Plants moved from the coolest treatment (1) to Treatment 2 temperature at 45 days after planting exhibited accelerated branching and production of dry matter, buds, and flowers, whereas transfer from Treatment 1 to Treatment 3 led to enhanced silique production. These results suggest that moving from a cold to a warmer temperature enhanced both biomass production and reproductive development. In addition to documenting the temperature impact on growth and reproductive development of lesquerella, the results provide evidence pertinent to defining growing regions suitable for cultivation of this new crop.
Impact of Dual‐Purpose Management on Wheat Grain Yield
Authors: Edwards J. T. , Carver B. F. , Horn G. W. , Payton M. E.
Published: August 2011

Farmers in the southern Great Plains utilize wheat (Triticum aestivum L.) as a forage and grain crop (dual purpose). The objective of this study was to evaluate the impact of dual‐purpose management on wheat grain yield using two multiyear data sets that included a diverse group of commercially released hard winter wheat cultivars and a limited number of advanced experimental breeding lines. Paired experiments were conducted from 1991 to 2010 at the Wheat Pasture Research Unit near Marshall, OK. Averaged across environments and years, grazing reduced wheat grain yield by 7% when both grazed and nongrazed plots were sown early to encourage lush forage growth. Regression analysis predicted an increase in wheat grain yield as a result of grazing in lower‐yielding (<1100 kg ha−1) environments but a decrease when nongrazed yield potential exceeded this value. When planting was manipulated to allow comparison of dual‐purpose and grain‐only systems, dual‐purpose management reduced grain yield by 14% as compared to grain‐only management. Grazing increased grain volume weight in both experiments by approximately 1%. Our results indicate that yield reductions in dual‐purpose wheat relative to grain‐only wheat arise due to the combination of grazing and earlier‐than‐optimal planting date.
Cold‐Induced Biochemical and Molecular Changes in Alfalfa Populations Selectively Improved for Freezing Tolerance
Authors: Castonguay Yves , Bertrand Annick , Michaud Réal , Laberge Serge
Published: August 2011

Synthetic populations obtained after successive cycles of recurrent selection for superior tolerance to freezing were used to probe the molecular bases of superior adaptation to cold in alfalfa (Medicago sativa L.). The initial genetic backgrounds and populations derived from the cultivars Apica and Evolution were assessed for their freezing tolerance and cold‐induced molecular changes using plants acclimated to natural hardening conditions in an unheated greenhouse. Significant increase in freezing tolerance in response to recurrent selection was confirmed by the determination of the lethal temperature for 50% of the plants (LT50). Improvement of freezing tolerance was associated with differences in cold‐induced molecular changes. Starch reserves in crowns progressively declined during fall hardening with a more extensive mobilization observed in advanced cycles of selection. Concentrations of cryoprotective sugars and of the amino acids proline, asparagine, and arginine increased during fall hardening and were significantly higher in recurrently selected populations than in the initial backgrounds. Transcript levels of two cold‐regulated (COR) genes, cas15 and GaS, were strongly up‐regulated during fall hardening and significantly increased in response to selection mostly in the Apica background. Our results provide evidence that recurrent selection for superior freezing tolerance in alfalfa induces marked changes in traits associated with the cold acclimation process.
Effectiveness of Sinorhizobium Inoculants on Annual Medics
Authors: Interrante Sindy M. , Singh Ruchi , Islam M. Anowarul , Stein Jimmy D. , Young Carolyn A. , Butler Twain J.
Published: August 2011

Annual medics (Medicago spp.) have potential to be important forage legumes in the southern Great Plains of the United States. Currently there are no commercial medic species‐specific rhizobia strains identified for their inoculation. However, commercially available alfalfa (Medicago sativa L.) inoculants may be effective at successfully nodulating annual medics. The objective of this study was to determine the relevant symbiotic rhizobial partner in association with seven annual medics. A greenhouse experiment arranged in three replications of a randomized complete block design quantified rhizobium effectiveness index and shoot and root dry matter (DM) of Medicago arabica (L.) Huds., Medicago lupulina L., Medicago minima (L.) Bartal., Medicago orbicularis (L.) Bartal., Medicago polymorpha L., Medicago rigidula (L.) All., and Medicago rigiduloides E. Small when inoculated with five Sinorhizobium spp. strains (M2, M49, Nitragin A, Nitragin N [a blend of three isolates], and WSM1115) and an untreated control (UTC). Strain M49 was the only strain that effectively nodulated M. rigiduloides, while Nitragin A commercial alfalfa strain was only effective on M. rigidula. Inoculants M2, Nitragin N, and WSM1115 were able to effectively nodulate M. polymorpha, M. arabica, M. minima, and M. orbicularis. To a lesser extent, M. lupulina, M. minima, and M. orbicularis were also effectively nodulated by Nitragin A alfalfa strain. These data indicate that there are differences in rhizobia specificity of annual medic species, and further research is warranted to improve nodulation of these legumes in the field.
Varying Planting Dates or Irrigation Regimes Alters Cottonseed Composition
Authors: Pettigrew William T. , Dowd Michael K.
Published: August 2011

Despite continued utilization of cottonseed (Gossypium hirsutum L.), little information exists regarding the effect of production factors on cottonseed composition. The objective of this study was to determine how irrigation regime and planting date affect cottonseed composition. Six cotton cultivars were planted early (late April) and at a normal time (late May) in a field near Stoneville, MS, from 2005 to 2008. Half of the plots were irrigated and half were cultivated dry. Seed from the 2006 through 2008 seasons were analyzed for protein, crude oil, gossypol, soluble carbohydrates, and the oil's fatty acid composition. Irrigation increased oil and total soluble carbohydrate levels by 7 and 4%, respectively, and reduced protein levels by 10%. Irrigation also increased the level of total gossypol by 21%, modestly decreased the percentage of the gossypol (+) isomer, and slightly decreased the level of saturated fatty acids in the oil. Early planting decreased gossypol in the seed kernel by 8% under dryland conditions but not under irrigated conditions. The early planting effect on the fatty acid distribution was similar to the effect observed under dryland conditions, but the differences were more modest. Early planting and irrigation offer potential for improved fiber and seed yield but with altered seed composition. Given the proper economic incentives, producers could alter some production strategies to produce seed with more valuable composition traits.
Use of New Generation Single Nucleotide Polymorphism Genotyping for Rapid Development of Near‐Isogenic Lines in Rice
Authors: Boualaphanh Chanthakhone , Daygon Venea D. , Calingacion Mariafe N. , Sanitchon Jarawit , Jothityangkoon Darunee , Mumm Roland , Hall Robert D. , Fitzgerald Melissa A.
Published: August 2011

Studies aimed at determining gene function or identity are greatly facilitated by introgression lines and phenotyping tools. However, developing introgression lines can take six to eight generations to reach the desired level of background purity and homozygosity. The objective of this study was to use new generation genome‐wide single nucleotide polymorphism (SNP) genotyping, along with a molecular marker for the allele of interest, and a relevant phenotyping tool, to develop research populations with just four generations of backcrossing. Two populations were created for future research on aroma in rice (Oryza sativa L.): one derived from two indica parents and the other from one indica and one tropical japonica parent. The same recurrent parent was used for both populations. Single nucleotide polymorphism genotyping of BC4F2 progeny selected previously on the basis of either a marker for fragrance or the presence of the fragrant compound and on the basis of morphological similarity to the recurrent parent showed that donor introgression ranged from <0.1% up to 35%. Single nucleotide polymorphism genotyping allowed the selection of a set of fragrant lines with minimal additional donor introgression after four generations. Metabolite profiling of the volatile blend in grains from parents and selected introgression lines showed that selected lines clustered with the recurrent parent. These new genotyping and phenotyping techniques enabled valuable genetic stocks to be developed in a short time for use in biochemical and genetic projects on fragrance in rice.
Establishment, Agronomic Characteristics, and Dry Matter Yield of Rhizoma Peanut Genotypes in Cool Environments
Authors: Interrante Sindy M. , Muir James P. , Islam M. Anowarul , Maas Andrea L. , Anderson William F. , Butler Twain J.
Published: August 2011

Rhizoma peanut (Arachis glabrata Benth.) has potential to provide high quality forage during summer months; however, establishment of the stand is slow and cold tolerance is limited. During the three growing seasons from 2006 to 2010, a randomized complete block design experiment was initiated at four locations, near Tifton, GA (2006, 2007, and 2008), Gene Autry, OK (2006), Burneyville, OK (2007 and 2008), and Vashti, TX (2007 and 2008), evaluating 16 rhizoma peanut genotypes for better establishment characteristics and cold tolerance. At the end of the establishment year, genotype A6 (PI 210555) had the greatest coverage (74%), followed by genotypes A156 and A160 (51 and 56%, respectively), while genotypes A10 and A42 had the least coverage (9 and 13%, respectively). The remaining genotypes were intermediate and generally did not differ from the released cultivars Florigraze, Arbrook, and Latitude 34, which had 25, 25, and 30% coverage, respectively. In the second season after establishment, genotypes Latitude 34 and A160 produced the greatest yields (1000 and 1360 kg ha−1, respectively). In the third season after establishment, Latitude 34 (3630 kg ha−1) outyielded all genotypes except A156 and A160 (2610 and 2260 kg ha−1, respectively). Therefore genotypes A160 and Latitude 34 consistently had the greatest coverage and production and may have greater cold tolerance. However, in the final year (2010), there were no genotypes that survived the winter.
Age and Aesthetic Significance in Classical Music: A Multi-Level Reanalysis of Halsey's (1976) Ratings
Authors: Kozbelt Aaron
Published: August 2011

Halsey (1976) provided quantitative ratings of the aesthetic significance of classical music masterworks, which have often been used in empirical studies of lifespan creativity. Previous research using the ratings suggests that composers overall show two career peaks, consistent with a recent “finder-seeker” creator typology. Here, ratings for 2533 works by 91 composers were reanalyzed using hierarchical linear modeling, which accounts for the nested structure of the data better than earlier multiple regression methods. In contrast to previous findings, results showed a single-peaked age function for aesthetic significance ratings. Composer-level variance in the slope of the trajectory was accounted for by total amount of masterpiece music composed and by career age at best work, even when those works were themselves removed from the dataset. This implies that composers show strong and consistent individual differences in career trajectories, which are interpreted via the “finder-seeker” typology.
Modelling and Control of Reactive Polymer Composite Moulding Using Bootstrap Aggregated Neural Network Models
Authors: Zhang Jie , Pantelelis Nikos G.
Published: August 2011

This paper presents using bootstrap aggregated neural networks for the modelling and optimisation control of reactive polymer composite moulding processes. Neural network models for the degree of cure are developed from process operational data. In order to improve model generalization capability, multiple neural networks are developed from bootstrap re-samples of the original data and are combined. Reliable optimal heating profiles are obtained by solving an optimisation problem using the bootstrap aggregated neural network model and incorporating model prediction confidence intervals in the optimisation objective function. The proposed method is applied to both simulated data and real industrial data.
Effects of washer on the stress distribution of mini-implant
Authors: Jang Hyoung-Jun , Kwon Soon-Yong , Kim Seong-Hun , Park Young-Guk , Kim Su-Jung
Published: August 2011

Objective:

To investigate the biomechanical effects of ‘washer’ designed for improving mini-implant stability.

Materials and Methods:

Four three-dimensional finite element models of the mini-implant and surrounding bone were constructed with washers in different spike lengths (1.5 mm, 2.0 mm, and 2.5 mm). The force was applied in two directions (45° and 90°). The stress distribution on surrounding bone and the displacement of the mini-implant were analyzed. Plots of tensile stress, compression stress, and displacement were calculated, and maximum values in each category were analyzed.

Results:

The stress distribution was different between the models with washer and without washer. However, no remarkable differences in stress distribution were observed among the models with washer, regardless of spike length. A significantly greater displacement value was observed in the model without washer compared to the models with washer, but no notable difference in displacement value was found among the models with washer. The plots of the displacement distribution of the models with washer presented notable pattern differences as compared with that of the model without washer.

Conclusion:

With the use of the washer, a more homogeneous distribution of bone stress and less displacement of the mini-implant can be achieved.
Enzymatic activity of yeasts isolated from the inflamed mammary secretion in dairy cows
Authors: Wawron W. , Bochniarz M. , Szczubiał M.
Published: August 2011

Enzymatic activity of yeasts isolated from the inflamed mammary secretion in dairy cows

The aim of the study was to evaluate enzymatic activities of yeasts isolated from inflammatory mammary secretion. The yeasts isolated from cows with clinical and sub-clinical mastitis (134 strains) included: Candida krusei (62 strains), Candida kefyr (48 strains), Candida lusitaniae (17 strains) and Candida famata (7 strains). The API ZYM system was used containing substrates to assess 19 hydrolytic enzymes. Substantial differences in the number and activity of hydrolyses were demonstrated in individual species. In Candida krusei, acid phosphatase showed the highest activity (4.36 points), in Candida kefyr and Candida lusitaniae - leucine arylamidase (4.93 and 4.25 points, respectively), in Candida famata - α-glucosidase (4.75 points). No activity of trypsin, chymotrypsin, α-galactosidase, β-glucuronidase, α-mannosidase or α-fucosidase was observed in any of the yeasts examined.
Immunohistochemical properties of motoneurons supplying the trapezius muscle in the rat
Authors: Dudek A. , Sienkiewicz W. , Marczak M. , Kaleczyc J.
Published: August 2011

Immunohistochemical properties of motoneurons supplying the trapezius muscle in the rat

Combined retrograde tracing (using fluorescent tracer Fast blue) and double-labelling immunofluorescence were used to study the distribution and immunohistochemical characteristics of neurons projecting to the trapezius muscle in mature male rats (n=9). As revealed by retrograde tracing, Fast blue-positive (FB+) neurons were located within the ambiguous nucleus and accessory nucleus of the grey matter of the spinal cord. Immunohistochemistry revealed that nearly all the neurons were cholinergic in nature [choline acetyltransferase (ChAT)-positive]. Retrogradely labelled neurons displayed also immunoreactivities to calcitonin gene-related peptide (CGRP; approximately 60% of FB+neurons), nitric oxide synthase (NOS; 50%), substance P (SP; 35%), Leu5-Enkephalin (LEnk; 10%) and vasoactive intestinal polypeptide (VIP; 5%). The analysis of double-stained tissue sections revealed that all CGRP-, VIP- and LEnk-immunoreactive FB+perikarya were simultaneously ChAT-positive. The vast majority of the neurons expressing SP- or NOS-immunoreactivity were also cholinergic in nature; however, solitary somata were ChAT-negative. FB+perikarya were surrounded by numerous varicose nerve fibres (often forming basket-like structures) immunoreactive to LEnk or SP. They were also associated with some CGRP-, NOS- and neuropeptide Y-positive nerve terminals.
Genetic comparison of Campylobacter jejuni isolated from different cattle farms
Authors: Bednarski M. , Wieliczko A. , Mazurkiewicz M.
Published: August 2011

Genetic comparison of Campylobacter jejuni isolated from different cattle farms

To compare the genotypes of Campylobacter jejuni, isolates of cattle origin were collected from 9 Polish farms and genotyped by ERIC-PCR. We identified 28 genotypes among the 43 C. jejuni isolates, and demonstrated high genomic diversity. The highest level of diversity was observed in strains isolated from stanchion-barn animals in opposition to those from the loose-housing system.
Changes in the blood coagulation profile after ovariohysterectomy in female dogs
Authors: Sobiech P. , Targoński R. , Stopyra A. , Żarczyńska K.
Published: August 2011

Changes in the blood coagulation profile after ovariohysterectomy in female dogs

This study investigated changes in the coagulation profile of 10 healthy female dogs subjected to ovariohysterectomy. Blood samples were collected three times - before, directly after and 24 h after surgery. Plasma samples were analyzed to determine thrombin time (TT), prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen content, D-dimer content and antithrombin (AT) III activity. The results revealed post-operative haemostatic system disorders related to prolonged APTT, higher fibrinogen and D-dimer concentrations and lower levels of AT III activity.
Transgenic mammalian species, generated by somatic cell cloning, in biomedicine, biopharmaceutical industry and human nutrition/dietetics - recent achievements
Authors: Samiec M. , Skrzyszowska M.
Published: August 2011

Transgenic mammalian species, generated by somatic cell cloning, in biomedicine, biopharmaceutical industry and human nutrition/dietetics - recent achievements

Somatic cell cloning technology in mammals promotes the multiplication of productively-valuable genetically engineered individuals, and consequently allows also for standardization of transgenic farm animal-derived products, which, in the context of market requirements, will have growing significance. Gene farming is one of the most promising areas in modern biotechnology. The use of live bioreactors for the expression of human genes in the lactating mammary gland of transgenic animals seems to be the most cost-effective method for the production/processing of valuable recombinant therapeutic proteins. Among the transgenic farm livestock species used so far, cattle, goats, sheep, pigs and rabbits are useful candidates for the expression of tens to hundreds of grams of genetically-engineered proteins or xenogeneic biopreparations in the milk. At the beginning of the new millennium, a revolution in the treatment of disease is taking shape due to the emergence of new therapies based on recombinant human proteins. The ever-growing demand for such pharmaceutical or nutriceutical proteins is an important driving force for the development of safe and large-scale production platforms. The aim of this paper is to present an overall survey of the state of the art in investigations which provide the current knowledge for deciphering the possibilities of practical application of the transgenic mammalian species generated by somatic cell cloning in biomedicine, the biopharmaceutical industry, human nutrition/dietetics and agriculture.
Gender Effects in Advertising
Authors: Cramphorn Michael F.
Published: August 2011

Less than 15% of ads are directed specifically to women and less than 5% are intended just for men. The remaining 80% are apparently targeted to everyone. This presumes very little difference in overall response between genders, which is strange, given that fundamental gender differences do exist. For example, women typically respond more positively to ads than men. Why should this be so? Is it intrinsic, is it cultural, or are there types of ads that work better with women than men, and vice versa? What leads to such differences? This paper reviews gender differences stemming from in-utero hormonal flows that shape the embryonic brain. How do such differences affect overall gender response to advertising? The findings show that advertising directed to just men or just women is more effective - yet paradoxically, it is seldom utilised, as most advertising appears to be targeted to both genders. In addition, although there is a wide range of effective styles of advertising and of content types that are demonstrably effective, many are comparatively neglected. Thus, there are opportunities for much more creativity and variety in the way advertising messages are communicated. The paper seeks to provide some clear pointers on how to go about this.
Quick, Simple and Reliable: Forced Binary Survey Questions
Authors: Dolnicar Sara , Grün Bettina , Leisch Friedrich
Published: August 2011

Consumers are increasingly saturated by market research, which leads to decreasing response rates and an increased danger of response bias. Market researchers thus face the challenge of recruiting respondents, increasing response rates and reducing respondent fatigue by making questionnaires as short and pleasant as possible. One way of achieving this is to replace traditionally used ordinal multi-category answer formats (such as Likert-type scales) with forced binary scales. This proposition is attractive only if it indeed shortens the survey time while not compromising the quality of managerial insights from the data. This study investigates these conditions. Results from a repeat-measurement design indicate that managerial interpretations do not differ substantially between the two answer formats, responses are equally reliable, and that the binary format is quicker and perceived as less complex.