bluuebunny/crossref_metadata_2025 huggingface dataset:
Different nonlinear functions in hippocampus and perirhinal cortex relating functional MRI activity to memory strength
Authors: Song Zhuang , Wixted John T. , Smith Christine N. , Squire Larry R.
Published: March 2011

Findings from functional MRI (fMRI) studies of recognition memory and the medial temporal lobe often suggest qualitative differences in the contribution of the hippocampus and perirhinal cortex. This interpretation is complicated by the fact that most of the methods intended to demonstrate qualitative differences also separate strong memories from weak memories. Thus, apparent qualitative differences might reflect quantitative differences in how measured activity in medial temporal lobe structures varies with memory strength. We tested the hypothesis that the relationship between activity at the time of study and subsequent memory strength is nonlinear in hippocampus and perirhinal cortex and also distinctly different in those two structures. We found that activity in the hippocampus was characterized by a positively accelerated function and that activity in the perirhinal cortex was associated with a statistically different, negatively accelerated function. Our results do not count against the possibility that these structures differ qualitatively in their contributions to memory. Rather, our findings show how an alternative interpretation based on quantitative differences can also account for a good deal of data, and they suggest that a demonstration of qualitative differences requires more stringent criteria than are achieved in most fMRI studies.
Regulation of T cell receptor signaling by activation-induced zinc influx
Authors: Yu Mingcan , Lee Won-Woo , Tomar Deepak , Pryshchep Sergey , Czesnikiewicz-Guzik Marta , Lamar David L. , Li Guangjin , Singh Karnail , Tian Lu , Weyand Cornelia M. , Goronzy Jörg J.
Published: March 2011

Zinc is a trace element that is essential for innate and adaptive immune responses. In addition to being a structural element of many proteins, zinc also functions as a neurotransmitter and an intracellular messenger. Temporal or spatial changes in bioavailable zinc may influence the activity of several enzymes, including kinases and phosphatases. We provide evidence that zinc functions as an ionic signaling molecule after T cell activation. Cytoplasmic zinc concentrations increased within 1 min after T cell receptor (TCR) triggering, in particular in the subsynaptic compartment. The increase depended on the extracellular zinc concentrations and was inhibited by silencing zinc transporter Zip6. Increased zinc influx reduced the recruitment of SHP-1 to the TCR activation complex, augmented ZAP70 phosphorylation and sustained calcium influx. By calibrating TCR activation thresholds, increased extracellular zinc bioavailability facilitated the induction of T cell proliferative responses to suboptimal stimuli.
G-CSF influences mouse skeletal muscle development and regeneration by stimulating myoblast proliferation
Authors: Hara Mie , Yuasa Shinsuke , Shimoji Kenichiro , Onizuka Takeshi , Hayashiji Nozomi , Ohno Yohei , Arai Takahide , Hattori Fumiyuki , Kaneda Ruri , Kimura Kensuke , Makino Shinji , Sano Motoaki , Fukuda Keiichi
Published: March 2011

After skeletal muscle injury, neutrophils, monocytes, and macrophages infiltrate the damaged area; this is followed by rapid proliferation of myoblasts derived from muscle stem cells (also called satellite cells). Although it is known that inflammation triggers skeletal muscle regeneration, the underlying molecular mechanisms remain incompletely understood. In this study, we show that granulocyte colony-stimulating factor (G-CSF) receptor (G-CSFR) is expressed in developing somites. G-CSFR and G-CSF were expressed in myoblasts of mouse embryos during the midgestational stage but not in mature myocytes. Furthermore, G-CSFR was specifically but transiently expressed in regenerating myocytes present in injured adult mouse skeletal muscle. Neutralization of endogenous G-CSF with a blocking antibody impaired the regeneration process, whereas exogenous G-CSF supported muscle regeneration by promoting the proliferation of regenerating myoblasts. Furthermore, muscle regeneration was markedly impaired in G-CSFR–knockout mice. These findings indicate that G-CSF is crucial for skeletal myocyte development and regeneration and demonstrate the importance of inflammation-mediated induction of muscle regeneration.
A novel isoform of the Ly108 gene ameliorates murine lupus
Authors: Keszei Marton , Detre Cynthia , Rietdijk Svend T. , Muñoz Pilar , Romero Xavier , Berger Scott B. , Calpe Silvia , Liao Gongxian , Castro Wilson , Julien Aimee , Wu Ying-Yu , Shin Dong-Mi , Sancho Jaime , Zubiaur Mercedes , Morse Herbert C. , Morel Laurence , Engel Pablo , Wang Ninghai , Terhorst Cox
Published: March 2011

Studies of human systemic lupus erythematosus patients and of murine congenic mouse strains associate genes in a DNA segment on chromosome 1 with a genetic predisposition for this disease. The systematic analysis of lupus-prone congenic mouse strains suggests a role for two isoforms of the Ly108 receptor in the pathogenesis of the disease. In this study, we demonstrate that Ly108 is involved in the pathogenesis of lupus-related autoimmunity in mice. More importantly, we identified a third protein isoform, Ly108-H1, which is absent in two lupus-prone congenic animals. Introduction of an Ly108-H1–expressing transgene markedly diminishes T cell–dependent autoimmunity in congenic B6.Sle1b mice. Thus, an immune response–suppressing isoform of Ly108 can regulate the pathogenesis of lupus.
Structure of the human activating natural cytotoxicity receptor NKp30 bound to its tumor cell ligand B7-H6
Authors: Li Yili , Wang Qian , Mariuzza Roy A.
Published: March 2011

Natural killer (NK) cells are lymphocytes of the innate immune system that participate in the elimination of tumor cells. In humans, the activating natural cytotoxicity receptors (NCRs) NKp30, NKp44, and NKp46 play a major role in NK cell–mediated tumor cell lysis. NKp30 recognizes B7-H6, a member of the B7 family which is expressed on tumor, but not healthy, cells. To understand the basis for tumor surveillance by NCRs, we determined the structure of NKp30, a member of the CD28 family which includes CTLA-4 and PD-1, in complex with B7-H6. The overall organization of the NKp30–B7-H6–activating complex differs considerably from those of the CTLA-4–B7 and PD-1–PD-L T cell inhibitory complexes. Whereas CTLA-4 and PD-1 use only the front β-sheet of their Ig-like domain to bind ligands, NKp30 uses both front and back β-sheets, resulting in engagement of B7-H6 via the side, as well as face, of the β-sandwich. Moreover, B7-H6 contacts NKp30 through the complementarity-determining region (CDR)–like loops of its V-like domain in an antibody-like interaction that is not observed for B7 or PD-L. This first structure of an NCR bound to ligand provides a template for designing molecules to stimulate NKp30-mediated cytolytic activity for tumor immunotherapy.
Flux identification for 1-𝐝 scalar conservation laws in the presence of shocks
Authors: Castro Carlos , Zuazua Enrique
Published: March 2011

We consider the problem of flux identification for 1-d scalar conservation laws formulating it as an optimal control problem. We introduce a new optimization strategy to compute numerical approximations of minimizing fluxes.

We first prove the existence of minimizers. We also prove the convergence of discrete minima obtained by means of monotone numerical approximation schemes, by a

Γ
\Gamma

-convergence argument. Then we address the problem of developing efficient descent algorithms. We first consider and compare the existing two possible approaches. The first one, the so-called discrete approach, based on a direct computation of gradients in the discrete problem and the so-called continuous one, where the discrete descent direction is obtained as a discrete copy of the continuous one. When optimal solutions have shock discontinuities, both approaches produce highly oscillating minimizing sequences and the effective descent rate is very weak. As a remedy we adapt the method of alternating descent directions that uses the recent developments of generalized tangent vectors and the linearization around discontinuous solutions, introduced by the authors, in collaboration with F. Palacios, in the case where the control is the initial datum. This method distinguishes descent directions that move the shock and those that perturb the profile of the solution away from it. As we shall see, a suitable alternating combination of these two classes of descent directions allows building more efficient and faster descent algorithms.
Prediction of microRNA targets in Caenorhabditis elegans using a self-organizing map
Authors: Heikkinen Liisa , Kolehmainen Mikko , Wong Garry
Published: March 2011

Motivation: MicroRNAs (miRNAs) are small non-coding RNAs that regulate transcriptional processes via binding to the target gene mRNA. In animals, this binding is imperfect, which makes the computational prediction of animal miRNA targets a challenging task. The accuracy of miRNA target prediction can be improved with the use of machine learning methods. Previous work has described methods using supervised learning, but they suffer from the lack of adequate training examples, a common problem in miRNA target identification, which often leads to deficient generalization ability.

Results: In this work, we introduce mirSOM, a miRNA target prediction tool based on clustering of short 3′-untranslated region (3′-UTR) substrings with self-organizing map (SOM). As our method uses unsupervised learning and a large set of verified Caenorhabditis elegans 3′-UTRs, we did not need to resort to training using a known set of targets. Our method outperforms seven other methods in predicting the experimentally verified C.elegans true and false miRNA targets.

Availability: mirSOM miRNA target predictions are available at http://kokki.uku.fi/bioinformatics/mirsom.

Contact:  liisa.heikkinen@uef.fi

Supplementary information:  Supplementary data are available at Bioinformatics online.
Rheological Properties of Starch‐Oil Composites with High Oil‐to‐Starch Ratios
Authors: Byars Jeffrey A. , Fanta George F. , Felker Frederick C.
Published: March 2011

Many applications have been developed for aqueous dispersions of jet‐cooked starch‐oil composites prepared by excess steam jet cooking. Previous formulations have typically contained 20–50% oil by weight based on the weight of starch. To expand the range of potential applications, new preparation methods were investigated to increase the oil content to as high as four times the weight of starch. High‐amylose corn starch was cooked in an excess‐steam jet cooker in the presence of oleic acid, and soybean oil was added to form the starch‐oil composites. Amylose is removed from solution by forming helical inclusion complexes with the oleic acid and, if the materials are cooled sufficiently quickly, the helical inclusion complexes only form small aggregates and shells around the oil droplets. Depending on the composition and preparation method, a wide range of stable, high‐oil materials from low‐viscosity liquids to smooth pastes can be formed. The flow, textural, and structural properties of these materials are shown. The materials can be used in a wide range of applications, including spray lubricants, lotions, and for fat delivery in cake mixes.
A Fast, Simple, and Reliable Method to Predict Pasta Yellowness
Authors: Fu B. X. , Schlichting L. , Pozniak C. J. , Singh A. K.
Published: March 2011

Pasta yellowness depends on the semolina carotenoid content, carotenoid degradation by lipoxygenase (LOX), and pasta processing conditions. In breeding programs, early generation lines are selected for high grain yellow pigment content with the intent to improve pasta color. This approach has been successful in increasing the grain yellow pigment of Canadian durum wheat in the last few decades. In recent years, however, a weak relationship between pasta yellowness (b*) as measured by a Minolta spectrophotometer and semolina yellow pigment content (r = 0.19–0.52) was noted in the Canadian durum wheat lines. Thus, total semolina yellow pigment content cannot effectively predict the yellowness of its pasta product. Therefore, a fast and simple method was developed to predict pasta yellowness by measuring semolina dough sheet color at different time intervals after sheeting (0.5, 2.0, and 24 hr). Spaghettis were processed from the semolina samples at two drying temperature cycles (70 and 90°C). There were significant correlations between dough sheet b* values at all three times and spaghetti b* values at both drying temperatures (r = 0.87–0.94). Semolina dough sheet can be easily prepared in 15 min and requires only 30 g of material. Shortly after sheeting (30 min), dough sheet b* values can be used to predict pasta yellowness without producing the end product (involving mixing, extrusion, and drying). In this study, we also found that dough sheet b* values increased significantly with time over the sampling intervals after sheeting for those breeding lines with superior pasta color. DNA analysis revealed that all those lines lacked the Lpx‐B1.1 duplication.
First Report of Sclerotinia Rot on Blueberry Caused by Sclerotinia sclerotiorum in Argentina
Authors: Perez B. A. , Farinon O. M. , Berretta M. F.
Published: March 2011

In October 2007, blighted shoots were observed on highbush blueberry (Vaccinium corymbosum L. cv. O'Neal) plants in La Plata, Buenos Aires Province, Argentina. Isolations from surface-disinfested shoots onto carrot agar and Spezieller Nahrstoffarmer Agar (SNA) consistently yielded white colonies that produced black sclerotia, mainly near the edge of the culture plates, after 7 days. Sclerotia were transferred to SNA tubes and kept at 5°C for several months. The germination of sclerotia produced numerous 6 mm long initials, stipitate pale brown cup-shaped apothecia (10 × 6 mm) with eight-spored asci (137 × 7 μm) at 18°C and continuous light conditions. Asci with uniseriate ascospores were cylindrical and narrow at the base. Ascospores (11 to 12 × 4 μm) were hyaline, unicellular, smooth, and ellipsoid. This isolated fungus was morphologically identified as Sclerotinia sclerotiorum (Lib.) de Bary (2,3). The isolate was deposited in the IMYZA Microbial Collection as INTA-IMC 87. Mycelium was cultured in 100 ml of Czapek's-Dox medium, supplemented with sucrose, peptone, yeast extract, sodium nitrate, and vitamins (1), for 3 days and fungal DNA was obtained using a DNA extraction kit. ITS1 and ITS2 of ribosomal genes were amplified by PCR using universal primers (4) and the PCR product was sequenced. A BLAST algorithm search revealed 100% identity of the sequence with 12 GenBank entries for S. sclerotiorum. The nucleotide sequence was deposited in the GenBank with Accession No. JF277567. Pathogenicity testing was achieved by placing detached leaves of cvs. Emerald, Misty, and Start on water agar (WA) plates, inoculating with 9-mm2 mycelial blocks, and incubating at 20°C with 12 h of light. Young shoots of highbush blueberry, Misty and O'Neal, were inoculated by the cut shoot method with micropipette tips filled with mycelium and kept under greenhouse conditions at 24°C and 14 h of light. On control plants, WA blocks or WA-filled micropipette tips were used. Leaf blight was observed after 5 to 6 days and sclerotia appeared after 7 days on inoculated tissues. Shoot blight was recorded on inoculated plants after 5 days. The fungus was reisolated from inoculated tissues, with no symptoms showing on controls. To our knowledge, this is the first report of Sclerotinia rot caused by S. sclerotiorum in blueberry in Argentina.

References: (1) J.F. Leslie and B. A. Summerell. The Fusarium Laboratory Manual. Blackwell Publishing, Hoboken, NJ, 2006. (2). J. E. M. Mourde and P. Holliday. No. 513 in: CMI Descriptions of Pathogenic Fungi and Bacteria. Kew, Surrey, UK, 1976. (3) S. Umemoto et al. Gen. Plant Pathol. 73:290, 2007. (4) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, 1990.
First Report of Passalora Leaf Spot Caused by Passalora bougainvilleae on Bougainvillea in Mexico
Authors: Ayala-Escobar V. , Santiago-Santiago V. , Madariaga-Navarrete A. , Castañeda-Vildozola A. , Nava-Diaz C.
Published: March 2011

Bougainvillea (Bougainvillea spectabilis Willd) growing in 28 gardens during 2009 showed 100% disease incidence and 3 to 7% disease severity. Bougainvilleas with white flowers were the most affected. Symptoms consisted of light brown spots with dark brown margins visible on adaxial and abaxial sides of the leaves. Spots were circular, 2 to 7 mm in diameter, often surrounded by a chlorotic halo, and delimited by major leaf veins. Single-spore cultures were incubated at 24°C under near UV light for 7 days to obtain conidia. Pathogenicity was confirmed by spraying a conidial suspension (1 × 104 spores/ml) on leaves of potted bougainvillea plants (white, red, yellow, and purple flowers), incubating the plants in a dew chamber for 48 h and maintaining them in a greenhouse (20 to 24°C). Identical symptoms to those observed at the residential gardens appeared on inoculated plants after 45 to 60 days. The fungus was reisolated from inoculated plants that showed typical symptoms. No symptoms developed on control plants treated with sterile distilled water. The fungus produced distinct stromata that were dark brown, spherical to irregular, and 20 to 24 μm in diameter. Conidiophores were simple, born from the stromata, loose to dense fascicles, brown, straight to curved, not branched, zero to two septate, 14 × 2 μm, with two to four conspicuous and darkened scars. The conidia formed singly, were brown, broad, ellipsoid, obclavate, straight to curved with three to four septa, 40 × 4 μm, and finely verrucous with thick hilum at the end. Fungal DNA from the single-spore cultures was obtained using a commercial DNA Extraction Kit (Qiagen, Valencia, CA); ribosomal DNA was amplified with ITS5 and ITS4 primers and sequenced. The sequence was deposited at the National Center for Biotechnology Information Database (GenBank Accession Nos. HQ231216 and HQ231217). The symptoms (4), morphological characteristics (1,2,4), and pathogenicity test confirm the identity of the fungus as Passalora bougainvilleae (Muntañola) Castañeda & Braun (= Cercosporidium bougainvilleae Muntañola). This pathogen has been reported from Argentina, Brazil, Brunei, China, Cuba, El Salvador, India, Indonesia, Jamaica, Japan, Thailand, the United States, and Venezuela (3). To our knowledge, this is the first report of this disease on B. spectabilis Willd in Mexico. P. bougainvilleae may become an important disease of bougainvillea plants in tropical and subtropical areas of Mexico.

References: (1) U. Braun and R. R. Castañeda. Cryptogam. Bot. 2/3:289, 1991. (2) M. B. Ellis. More Dematiaceous Hypomycetes. Commonwealth Mycological Institute, Kew, Surrey, UK, 1976. (3) C. Nakashima et al. Fungal Divers. 26:257, 2007. (4) K. L. Nechet and B. A. Halfeld-Vieira. Acta Amazonica 38:585, 2008.
Identification of Resistance to Multiple Fungicides in Field Populations of Venturia inaequalis
Authors: Chapman Kimberly S. , Sundin George W. , Beckerman Janna L.
Published: March 2011

Venturia inaequalis, the causal agent of apple scab, is controlled primarily by fungicides. Long-term, extensive fungicide use has led to the development of resistance to multiple fungicides. To assess fungicide resistance, isolates of V. inaequalis were collected from Indiana and Michigan orchards. Single-spore derived isolates were evaluated by mycelium growth assays with previously determined discriminatory doses on media containing dodine, kresoxim-methyl, myclobutanil, or thiophanate-methyl. Of 195 isolates tested, 5.2, 0.7, 57.0, and 92.6% of isolates were found to be resistant to dodine, kresoxim-methyl, myclobutanil, and thiophanate-methyl, respectively. This is the first report of kresoxim-methyl field resistance in these states. Isolates resistant or shifted to a single fungicide were often found to have multiple fungicide resistance. Of all isolates tested, 38% were identified as resistant or shifted to two fungicides, and 12% were resistant or shifted to all four fungicides tested. No fitness penalty was found for isolates resistant to multiple fungicides based on a statistical analysis of mycelial growth and conidial production.
Improved Resistance Against Botrytis cinerea by Grapevine-Associated Bacteria that Induce a Prime Oxidative Burst and Phytoalexin Production
Authors: Verhagen Bas , Trotel-Aziz Patricia , Jeandet Philippe , Baillieul Fabienne , Aziz Aziz
Published: March 2011

Bacteria such as Pantoea agglomerans (Pa-AF2), Bacillus subtilis (Bs-271), Acinetobacter lwoffii (Al-113), and Pseudomonas fluorescens (Pf-CT2), originating from the vineyard, can induce defense responses and enhance resistance of grapevine against the fungal pathogen Botrytis cinerea. The perception of these bacteria by plant cells or tissues in relation to their activities remains unknown. In this study, we examined the relationships between the activity of each bacterium to induce or prime some defense responses, and its effectiveness to induce resistance in grapevine against B. cinerea. We showed that all selected bacteria are capable of inducing early oxidative burst and phytoalexin (trans-resveratrol and trans-ε-viniferin) production in grapevine cells and leaves. Pf-CT2 and Al-113 induced higher H2O2 and trans-resveratrol accumulations, and were able to further prime plants for accelerated phytoalexin production after B. cinerea challenge. These two bacteria were also the most effective in inducing local and systemic resistance. A similar level of induced resistance was observed with live Pa-AF2 which also induced but not primed a greater accumulation of trans-resveratrol. However, Bs-271, which was less effective in inducing resistance, induced a lower trans-resveratrol synthesis, without priming activity. Treatment of grapevine cells with growing medium or crude extract of the bacteria quickly and strongly enhanced oxidative burst compared with the live bacteria. However, both treatments resulted in comparable amounts of phytoalexins and induced local and systemic resistance to B. cinerea as compared with those induced by living bacteria, with extracts from Pf-CT2 and Al-113 being the most effective. Together, these results indicate that induced resistance can be improved by treatment with bacteria or derived compounds which induced or primed plants for enhanced phytoalexin accumulation.
Vegetative Compatibility Groups and Parasexual Segregation in Colletotrichum acutatum Isolates Infecting Different Hosts
Authors: da Silva Franco Claudinéia Conationi , de Sant' Anna Juliane Rocha , Rosada Lúcia Jacovozzi , Kaneshima Edilson Nobuyoshi , Stangarlin José Renato , De Castro-Prado Marialba Avezum Alves
Published: March 2011

Heterokaryosis is an important mechanism which provides genetic variability increase in filamentous fungi. In order to assess the diversity of vegetative compatibility reactions existing among Colletotrichum acutatum isolates derived from different hosts, complementary nit mutants of each isolate were obtained and paired in all possible combinations. Vegetative compatibility groups (VCG) were identified among the isolates according to their ability to form viable heterokaryons. Seven VCGs were identified among the isolates, one of which contained isolates from different hosts. VCGs 2 and 6 contained two and three members, respectively; VCG-3 contained four members, and four VCGs (1, 4, 5, and 7) contained a single one. This study shows, for the first time, the isolation and the parasexual segregation of a heterozygous diploid sector derived from the heterokaryon formed with nit mutants from VCG-6. Diploid, named DE-3, showed nit+ phenotype and growth rate similar to the parental wild isolate. When inoculated in the presence of the haploidizing agent benomyl, the diploid strain produced parasexual haploid segregants exhibiting the nit phenotypes of the crossed mutants. Since viable heterokaryons and diploid may be formed among vegetative compatible isolates of C. acutatum, this study suggests that the parasexual cycle may be an alternative source of genetic variability in C. acutatum isolates.
Rhizobium taibaishanense sp. nov., isolated from a root nodule of Kummerowia striata
Authors: Yao Li Juan , Shen Yao Yao , Zhan Jun Peng , Xu Wei , Cui Guang Ling , Wei Ge Hong
Published: March 2011

During a study of the diversity and phylogeny of rhizobia in the root nodules of Kummerowia striata grown in north-western China, four strains were classified in the genus Rhizobium on the basis of their 16S rRNA gene sequences. The 16S rRNA gene sequences of three of these strains were identical and that of the other strain, which was the only one isolated in Yangling, differed from the others by just 1 bp. The16S rRNA gene sequences of the four strains showed a mean similarity of 99.3 % with the most closely related, recognized species, Rhizobium vitis. The corresponding recA and glnA gene sequences showed similarities with established species of Rhizobium of less than 86.5 % and less than 89.6 %, respectively. These low similarities indicated that the four strains represented a novel species of the genus Rhizobium. The strains were also found to be distinguishable from the closest related, established species (R. vitis) by rep-PCR DNA fingerprinting, analysis of cellular fatty acid profiles and from the results of a series of phenotypic tests. The level of DNA–DNA relatedness between the representative strain CCNWSX 0483T and Rhizobium vitis IAM 14140T was only 40.13 %. Therefore, a novel species, Rhizobium taibaishanense sp. nov., is proposed, with strain CCNWSX 0483T ( = ACCC 14971T = HAMBI 3214T) as the type strain. In nodulation and pathogenicity tests, none of the four strains of Rhizobium taibaishanense sp. nov. was able to induce any nodule or tumour formation on plants. As no amplicons were detected when DNA from the strains was run in PCR with primers for the detection of nodA, nifH and virC gene sequences, the strains probably do not carry sym or vir genes.
Revealing the genetic structure of a trait by sequencing a population under selection
Authors: Parts Leopold , Cubillos Francisco A. , Warringer Jonas , Jain Kanika , Salinas Francisco , Bumpstead Suzannah J. , Molin Mikael , Zia Amin , Simpson Jared T. , Quail Michael A. , Moses Alan , Louis Edward J. , Durbin Richard , Liti Gianni
Published: March 2011

One approach to understanding the genetic basis of traits is to study their pattern of inheritance among offspring of phenotypically different parents. Previously, such analysis has been limited by low mapping resolution, high labor costs, and large sample size requirements for detecting modest effects. Here, we present a novel approach to map trait loci using artificial selection. First, we generated populations of 10–100 million haploid and diploid segregants by crossing two budding yeast strains of different heat tolerance for up to 12 generations. We then subjected these large segregant pools to heat stress for up to 12 d, enriching for beneficial alleles. Finally, we sequenced total DNA from the pools before and during selection to measure the changes in parental allele frequency. We mapped 21 intervals with significant changes in genetic background in response to selection, which is several times more than found with traditional linkage methods. Nine of these regions contained two or fewer genes, yielding much higher resolution than previous genomic linkage studies. Multiple members of the RAS/cAMP signaling pathway were implicated, along with genes previously not annotated with heat stress response function. Surprisingly, at most selected loci, allele frequencies stopped changing before the end of the selection experiment, but alleles did not become fixed. Furthermore, we were able to detect the same set of trait loci in a population of diploid individuals with similar power and resolution, and observed primarily additive effects, similar to what is seen for complex trait genetics in other diploid organisms such as humans.
Altered gene regulation and synaptic morphology in Drosophila learning and memory mutants
Authors: Guan Zhuo , Buhl Lauren K. , Quinn William G. , Littleton J. Troy
Published: March 2011

Genetic studies in Drosophila have revealed two separable long-term memory pathways defined as anesthesia-resistant memory (ARM) and long-lasting long-term memory (LLTM). ARM is disrupted in radish (rsh) mutants, whereas LLTM requires CREB-dependent protein synthesis. Although the downstream effectors of ARM and LLTM are distinct, pathways leading to these forms of memory may share the cAMP cascade critical for associative learning. Dunce, which encodes a cAMP-specific phosphodiesterase, and rutabaga, which encodes an adenylyl cyclase, both disrupt short-term memory. Amnesiac encodes a pituitary adenylyl cyclase-activating peptide homolog and is required for middle-term memory. Here, we demonstrate that the Radish protein localizes to the cytoplasm and nucleus and is a PKA phosphorylation target in vitro. To characterize how these plasticity pathways may manifest at the synaptic level, we assayed synaptic connectivity and performed an expression analysis to detect altered transcriptional networks in rutabaga, dunce, amnesiac, and radish mutants. All four mutants disrupt specific aspects of synaptic connectivity at larval neuromuscular junctions (NMJs). Genome-wide DNA microarray analysis revealed ∼375 transcripts that are altered in these mutants, suggesting defects in multiple neuronal signaling pathways. In particular, the transcriptional target Lapsyn, which encodes a leucine-rich repeat cell adhesion protein, localizes to synapses and regulates synaptic growth. This analysis provides insights into the Radish-dependent ARM pathway and novel transcriptional targets that may contribute to memory processing in Drosophila.
Proactive improvement of logistics service providers as driver of customer loyalty
Authors: Marcus Wallenburg Carl , Lukassen Peter
Published: March 2011

Purpose

The purpose of this paper is to provide a differentiated view of relationship‐specific proactive improvement of logistics service providers (LSPs) that distinguishes between the cost and performance and the effect that these two dimensions of innovation have on three distinct customer loyalty dimensions (retention, extension, and referrals).

Design/methodology/approach

A confirmatory empirical study was conducted based on social exchange theory and customer value theory. The survey responses from 298 firms were analysed using structural equation modelling and multi‐group analysis to test for direct effects and moderation.

Findings

Both dimensions of relationship‐specific proactive improvement by LSPs (cost and performance) are strong drivers of all three customer loyalty dimensions and, thus, are important to customer relationship management and relevant areas to be considered within innovation management. The effect on customer loyalty is moderated by the dynamism of the customer's market. Proactive cost improvements are more important under high dynamism, while proactive performance improvements, contrary to initial assumptions, are more important when dynamism is low.

Research limitations/implications

Future studies should analyse other cultural settings, differentiate between functional and relationship value provided, consider other services, investigate how LSPs can facilitate proactive improvement and improve innovation management, and explore how customers can foster proactive improvement.

Practical implications

The currently low level of proactive improvement should be increased if LSPs want to enhance customer loyalty. In doing so, LSPs ought to consider the dynamism of their customers' markets.

Originality/value

The paper is the first to provide a differentiated view on the role of relationship‐specific proactive innovation that distinguishes between cost and performance improvements and illustrates their effects on three distinct customer loyalty dimensions.
Consumer complicity with counterfeit products
Authors: Chaudhry Peggy E. , Stumpf Stephen A.
Published: March 2011

Purpose

The purpose of this paper is to guide marketing managers in their efforts to decrease consumer demand for counterfeits of their products by examining the consumer beliefs and attitudes that have been found to support consumer complicity across multiple products, in virtual and physical shopping environments, using several criteria of complicity for each product.

Design/methodology/approach

A web‐based survey of 254 students explored two ethical ideologies (idealism and relativism), collectivism, and two attitudes toward counterfeits (ethical concern and perceived quality) with respect to two counterfeit products (movies and pharmaceuticals) and reported respondents' complicity in both a virtual and physical marketplace for each good.

Findings

Consumer complicity – a consumer's willingness to obtain, share, or use counterfeit products – was predicted by the consumers' hedonic shopping experience and lack of ethical concern with two different counterfeit products. The effects of ethical ideologies and collectivism on consumer complicity were observed to operate indirectly through hedonic shopping and ethical concern with using counterfeits.

Research limitations/implications

The primary limitation is the use of a convenience sample of US college students and future research should take the scale items developed in this study and test in multiple country markets.

Originality/value

The paper extends previous research by examining several identified predictors of complicity with different products, across virtual and physical markets, and with multiple criteria incorporating both acquisition, intent to acquire, and willingness to share.
How to use statistics to survive – a personal story
Authors: Sacchetti Luciana , Iannucci Paola , Tosi Simona
Published: March 2011

Purpose

The purpose of this paper is to present a personal story about the use of statistics to help protect library services at the Library of the Department of Statistics at Bologna University.

Design/methodology/approach

This paper describes the statistics used uncritically by the Centralized Library Services of the University, their inadequacy, and greater utility of the data gathered by the Statistics Library together with those of the University of Ferrara.

Findings

The data gathered by the Statistics Library and those of the University of Ferrara provided a richer and more valid image of their services and their value to the user community, than the limited, somewhat old‐fashioned and simplistic metrics of the Centralized Library Services.

Originality/value

This successful approach helped change the mind of senior library management at a time of retrenchment. It is hoped that it will inspire others to challenge simplistic snapshots of services and strengthen their cases with more representative data.
SB‐656933, a novel CXCR2 selective antagonist, inhibits ex vivo neutrophil activation and ozone‐induced airway inflammation in humans
Authors: Lazaar Aili L. , Sweeney Lisa E. , MacDonald Alexander J. , Alexis Neil E. , Chen Chao , Tal‐Singer Ruth
Published: March 2011

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

• Receptor antagonists that block the binding of chemokines such as CXCL8 (IL‐8) are effective in animals models of neutrophil‐mediated inflammation.

• It has been hypothesized that selective inhibition of neutrophil trafficking and activation may be a useful adjunct for the treatment of inflammatory airway diseases such as chronic obstructive pulmonary disease or cystic fibrosis. A CXCR1/2 receptor antagonist has shown activity in an ozone challenge model in humans.

WHAT THIS STUDY ADDS

• SB‐656933, a selective CXCR2 antagonist, is safe and well‐tolerated at single doses and is shown to inhibit agonist (CXCL1)‐mediated expression of the CD11b on peripheral blood neutrophils as well as ozone‐induced airway neutrophilia in healthy subjects.

AIMS To determine the safety and tolerability of a novel selective CXCR2 antagonist and assess its pharmacodynamic effects using measures of neutrophil activation and function, including CD11b expression in whole blood and ozone‐induced airway inflammation in healthy subjects.

METHODS Flow cytometric determination of ex vivo CXCL1‐induced CD11b expression on peripheral blood neutrophils was performed following single dose oral administration of SB‐656933 (dose range 2–1100 mg). A subsequent randomized study (placebo, 50 mg and 150 mg) was performed to explore the dose–response for ozone‐induced airway inflammation, as measured by sputum biomarkers.

RESULTS Oral administration of SB‐656933 resulted in significant inhibition of CXCL1‐induced CD11b expression on peripheral blood neutrophils at single doses greater than or equal to 50 mg. Maximum inhibition (70%) relative to placebo was observed following administration of SB‐656933 400 mg (95% CI 60%, 77%). This was sustained up to a dose of 1100 mg. Single doses of SB‐656933 reduced ozone‐induced airway inflammation in a dose‐dependent manner. Relative to placebo, there were 55% (95% CI 20%, 75%) and 74% (95% CI 55%, 85%) fewer neutrophils in the sputum of subjects after a single dose of 50 mg or 150 mg, respectively. There was a corresponding reduction in myeloperoxidase concentrations in the sputum supernatant of 32.8% (95% CI 9.2, 50.3) and 50.5% (95% CI 33.3, 63.3). SB‐656933 was safe and well‐tolerated at all doses.

CONCLUSIONS SB‐656933 is a CXCR2 antagonist that demonstrates dose‐dependent effects on neutrophil activation and recruitment within a well‐tolerated dose range. These data suggest that SB‐656933 may be an effective agent in neutrophil‐predominant diseases.
Standard clinical practice underestimates the role and significance of erythropoietin deficiency in sickle cell disease
Authors: Saraf Santosh , Farooqui Mohammed , Infusino Giovanni , Oza Bharvi , Sidhwani Seema , Gowhari Michel , Vara Stephen , Gao Weihua , Krauz Lani , Lavelle Donald , DeSimone Joseph , Molokie Robert , Saunthararajah Yogen
Published: March 2011

In sickle cell disease (SCD), vigorous reticulocytosis is required to partially compensate for chronic hemolytic anaemia. Consequently, early renal damage, insufficient to cause azotemia but sufficient to cause erythropoietin deficiency and chronic relative reticulocytopenia (chRR), could have severe clinical consequences. chRR was defined as reticulocytes <250 × 109/l despite haemoglobin <9 g/dl on ≥ two occasions ≥4 weeks apart. The influence of multiple variables including chRR on time from first clinic visit to death was evaluated in 306 SCD patients. In univariate analyses, fetal haemoglobin, indices of renal damage (serum creatinine, proteinuria), chRR and age, were associated with rate of death. In multivariate analysis, only age and chRR (Hazard ratio 3·6, 95% CI 2·049–6·327, P < 0·0001) were significant, underlining that chRR could be an early and important clinical consequence of renal damage. Even in chRR patients with normal serum creatinine levels, low haemoglobin and low reticulocyte counts were associated with low erythropoietin levels. In the general population, evaluation of erythropoietin levels is prompted by the combination of anaemia and abnormal serum creatinine. In SCD patients, this standard approach can miss a substantial risk factor for early death. chRR could be a practical and important criterion for diagnosis of erythropoietin deficiency in SCD.
Expression of blood group genes by mesenchymal stem cells
Authors: Schäfer Richard , Schnaidt Martina , Klaffschenkel Roland A. , Siegel Georg , Schüle Michael , Rädlein Maria Anna , Hermanutz‐Klein Ursula , Ayturan Miriam , Buadze Marine , Gassner Christoph , Danielyan Lusine , Kluba Torsten , Northoff Hinnak , Flegel Willy A.
Published: March 2011

Incompatible blood group antigens are highly immunogenic and can cause graft rejections. Focusing on distinct carbohydrate‐ and protein‐based membrane structures, defined by blood group antigens, we investigated human bone marrow‐derived mesenchymal stem cells (MSCs) cultured in human serum. The presence of H (CD173), ABO, RhD, RhCE, RhAG, Kell, urea transporter type B (SLC14A1, previously known as JK), and Duffy antigen receptor of chemokines (DARC) was evaluated at the levels of genome, transcriptome and antigen. Fucosyltransferase‐1 (FUT1), RHCE, KEL, SLC14A1 (JK) and DARC mRNA were transcribed in MSCs. FUT1 mRNA transcription was lost during differentiation. The mRNA transcription of SLC14A1 (JK) decreased during chondrogenic differentiation, while that of DARC increased during adipogenic differentiation. All MSCs synthesized SLC14A1 (JK) but no DARC protein. However, none of the protein antigens tested occurred on the surface, indicating a lack of associated protein function in the membrane. As A and B antigens are neither expressed nor adsorbed, concerns of ABO compatibility with human serum supplements during culture are alleviated. The H antigen expression by GD2dim+ MSCs identified two distinct MSC subpopulations and enabled their isolation. We hypothesize that GD2dim+ H+ MSCs retain a better ‘stemness’. Because immunogenic blood group antigens are lacking, they cannot affect MSC engraftment in vivo, which is promising for clinical applications.
Variation in pea aphid population development in three different habitats
Authors: BOMMARCO RICCARDO , EKBOM BARBARA
Published: March 2011

Abstract.

Seasonal population growth rates for the pea aphid, Acyrthosiphon pisum Harris, were determined in three different host plant habitats; alfalfa, Medicago sativa (L.), clover, Trifolium pratense (L.), and peas, Pisum sativum (L.); over four years and eight places. It was possible to estimate a common intrinsic rate of increase for each host plant habitat.

An analysis of the relative influence of temporal, spatial and host plant habitat variation showed that the host plant habitat was most important in determining the growth rates of the populations, both in rate of build‐up and decline.

Patterns of alate production in the three different habitats differed substantially between the annual peas and the two perennial legumes. During the summer, alate production was large and rapid in peas and remained low and constant in clover and alfalfa

Parasitism was highest in peas. The species composition of parasitoids differed between crops.

Aphids in annual peas had a higher intrinsic rate of increase and a faster rate of decline than in the two perennial legumes. This explains the presence of both migratory and sedentary forms among pea aphids.
A pilot analysis of gut contents in termites from the Mbalmayo Forest Reserve, Cameroon
Authors: SLEAFORD F. , BIGNELL DAVID E. , EGGLETON P.
Published: March 2011

Abstract.

Gut content analysis was carried out on eight species of higher termites representing the four included subfamilies and notional soil‐feeding and wood‐feeding forms. A lower termite species feeding on wood was also examined.

Pooled homogenates equivalent in volume to twenty hindguts of Thoracotermes macrothorax were diluted, stained and scored present/absent in 500 haemacytometer fields for ten content item categories: macerated organic material, lignified tissue, plant tissue fragments, fungal mycelium, arthropod parts, plant roots, safranin +ve, gentian violet +ve, humus and silica. For interspecific comparisons, the occurrence of each category was expressed as a proportion of the total haemacytometer cells examined.

A hierarchical classification of the species, based on gut contents, was prepared using a two‐way indicator species analysis, and suggested the following rank order of species along a hypothetical humification gradient (soil to sound wood): Thoracotermes macrothorax, Astalotermes quietus (both soil‐feeders), Termes hospes, Amalotermes phaecocephalus, Pseudacanthotermes militaris, Microtermes congoensis, Nasutitermes lujae, Microcerotermes parvus, Schedorhinotermes putorius (all notional wood‐feeders). Arthropod parts, silica and humus were identified as indicator factors.

It is proposed that wood‐feeding forms can be subdivided into a group consuming some silica and humus (five species: humified wood‐feeders) and a second group of sound wood‐feeders (two species).

Pianka's equations for diet breadth and diet overlap were also applied to the data. These identified Microtermes congoensis, Schedorhinotermes putorius and Pseudacanthotermes militaris as the most specialized feeders, i.e. that they can extract their nutrients from the least heterogenous substrates.
A new experimental approach to investigate migration in Pieris brassicae L.
Authors: SPIETH HUBERT R. , KASCHUBA‐HOLTGRAVE ANDREAS
Published: March 2011

Abstract.

It is possible to correlate distinct sequences of flight behaviour in caged females of the migrant butterfly Pieris brassicae with the main flight direction of released individuals of the same stock. The attempts to escape out of the cage point to the same mean direction as the flights of the released butterflies. This provides an experimental tool to investigate some unsolved questions concerning migration behaviour.

This study examines the constancy of the flight direction of a group of butterflies, the specificity of the direction in two populations of different geographical origin, and the frequently reported change in flight direction of subsequent generations.

The results indicate that the main flight direction of a tested group is very constant during 2 days of observation. Different directions have been detected in populations originating from Northern Germany and Southern France, respectively. The preferred directions are discussed as an adaptation to the geographical circumstances. Subsequent generations of the population from Northern Germany also show different directions. The spring generation flies to the north, the autumn generation in the opposite direction. This result corresponds to field observations that in P.brassicae a return flight occurs in subsequent generations of a year.
Sensory characterisation and oxidative stability of walnut oil
Authors: Martínez Marcela , Barrionuevo Guillermina , Nepote Valeria , Grosso Nelson , Maestri Damián
Published: March 2011

This study was carried out in order to probe the extent of oxidative and flavour stability of walnut oil (WO) under conditions normally used for selling in retail markets, during a period of four months. Fresh WO was characterised by higher intensity ratings of nutty and oily film, and lesser ratings for pungent and astringent attributes. Low and similar values for sweetness and bitterness were also detected. The ratings for negative attributes (oxidised and painty) were close to zero. During the long‐term storage period, the extent of the oil oxidative degradation was more pronounced than flavour attributes deterioration. Peroxide values (PV), conjugated dienes and trienes increased significantly throughout the storage period, whereas tocopherol content and oxidative stability index showed significant reductions. Minor changes were observed in the overall flavour stability. Using a PV of 10 mequiv. O2 kg−1 oil as a quality criterion, WO stored in transparent glass bottles, exposed to fluorescent light (1100 Lux) and room temperature conditions, without addition of any antioxidant, could maintain an acceptable quality until two months of storage.