bluuebunny/crossref_metadata_2025 huggingface dataset:
Expert assessments of the cost of light water small modular reactors
Authors: Abdulla Ahmed , Azevedo Inês Lima , Morgan M. Granger
Published: May 2013

Analysts and decision makers frequently want estimates of the cost of technologies that have yet to be developed or deployed. Small modular reactors (SMRs), which could become part of a portfolio of carbon-free energy sources, are one such technology. Existing estimates of likely SMR costs rely on problematic top-down approaches or bottom-up assessments that are proprietary. When done properly, expert elicitations can complement these approaches. We developed detailed technical descriptions of two SMR designs and then conduced elicitation interviews in which we obtained probabilistic judgments from 16 experts who are involved in, or have access to, engineering-economic assessments of SMR projects. Here, we report estimates of the overnight cost and construction duration for five reactor-deployment scenarios that involve a large reactor and two light water SMRs. Consistent with the uncertainty introduced by past cost overruns and construction delays, median estimates of the cost of new large plants vary by more than a factor of 2.5. Expert judgments about likely SMR costs display an even wider range. Median estimates for a 45 megawatts-electric (MWe) SMR range from $4,000 to $16,300/kWeand from $3,200 to $7,100/kWefor a 225-MWeSMR. Sources of disagreement are highlighted, exposing the thought processes of experts involved with SMR design. There was consensus that SMRs could be built and brought online about 2 y faster than large reactors. Experts identify more affordable unit cost, factory fabrication, and shorter construction schedules as factors that may make light water SMRs economically viable.
Citron kinase controls a molecular network required for midbody formation in cytokinesis
Authors: Bassi Zuni I. , Audusseau Morgane , Riparbelli Maria Giovanna , Callaini Giuliano , D’Avino Pier Paolo
Published: May 2013

Cytokinesis partitions cytoplasmic and genomic materials at the end of cell division. Failure in this process causes polyploidy, which in turn can generate chromosomal instability, a hallmark of many cancers. Successful cytokinesis requires cooperative interaction between contractile ring and central spindle components, but how this cooperation is established is poorly understood. Here we show that Sticky (Sti), the
Drosophila
ortholog of the contractile ring component Citron kinase (CIT-K), interacts directly with two kinesins, Nebbish [the fly counterpart of human kinesin family member 14 (KIF14)] and Pavarotti [the
Drosophila
ortholog of human mitotic kinesin-like protein 1 (MKLP1)], and that in turn these kinesins interact with each other and with another central spindle protein, Fascetto [the fly ortholog of protein regulator of cytokinesis 1 (PRC1)]. Sti recruits Nebbish to the cleavage furrow, and both proteins are required for midbody formation and proper localization of Pavarotti and Fascetto. These functions require Sti kinase activity, indicating that Sti plays both structural and regulatory roles in midbody formation. Finally, we show that CIT-K’s role in midbody formation is conserved in human cells. Our findings indicate that CIT-K is likely to act at the top of the midbody-formation hierarchy by connecting and regulating a molecular network of contractile ring components and microtubule-associated proteins.
HHLA2 is a member of the B7 family and inhibits human CD4 and CD8 T-cell function
Authors: Zhao Ruihua , Chinai Jordan M. , Buhl Susan , Scandiuzzi Lisa , Ray Anjana , Jeon Hyungjun , Ohaegbulam Kim C. , Ghosh Kaya , Zhao Aimin , Scharff Matthew D. , Zang Xingxing
Published: May 2013

T-cell costimulation and coinhibition generated by engagement of the B7 family and their receptor CD28 family are of central importance in regulating the T-cell response, making these pathways very attractive therapeutic targets. Here we describe HERV–H LTR-associating protein 2 (HHLA2) as a member of the B7 family that shares 10–18% amino acid identity and 23–33% similarity to other human B7 proteins and phylogenetically forms a subfamily with B7x and B7-H3 within the family. HHLA2 is expressed in humans but not in mice, which is unique within the B7 and CD28 families. HHLA2 protein is constitutively expressed on the surface of human monocytes and is induced on B cells after stimulation with LPS and IFN-γ. HHLA2 does not interact with other known members of the CD28 family or the B7 family, but does bind a putative receptor that is constitutively expressed not only on resting and activated CD4 and CD8 T cells but also on antigen-presenting cells. HHLA2 inhibits proliferation of both CD4 and CD8 T cells in the presence of T-cell receptor signaling. In addition, HHLA2 significantly reduces cytokine production by T cells including IFN-γ, TNF-α, IL-5, IL-10, IL-13, IL-17A, and IL-22. Thus, we have identified a unique B7 pathway that is able to inhibit human CD4 and CD8 T-cell proliferation and cytokine production. This unique human T-cell coinhibitory pathway may afford unique strategies for the treatment of human cancers, autoimmune disorders, infection, and transplant rejection and may help to design better vaccines.
Antibody to a conserved antigenic target is protective against diverse prokaryotic and eukaryotic pathogens
Authors: Cywes-Bentley Colette , Skurnik David , Zaidi Tanweer , Roux Damien , DeOliveira Rosane B. , Garrett Wendy S. , Lu Xi , O’Malley Jennifer , Kinzel Kathryn , Zaidi Tauqeer , Rey Astrid , Perrin Christophe , Fichorova Raina N. , Kayatani Alexander K. K. , Maira-Litràn Tomas , Gening Marina L. , Tsvetkov Yury E. , Nifantiev Nikolay E. , Bakaletz Lauren O. , Pelton Stephen I. , Golenbock Douglas T. , Pier Gerald B.
Published: May 2013

Significance

Poly-
N
-acetylglucosamine (PNAG) has been identified as a conserved surface polysaccharide produced by major bacterial, fungal, and protozoal parasites, including malarial sporozoites and blood-stage forms, which can all be targeted for vaccination using this single antigen. Surface carbohydrates are among the most successful vaccines against human microbial pathogens but have tremendous variability that complicates vaccine development. The species of bacteria, fungi, and protozoa shown here to produce PNAG lack an identifiable genetic locus for this antigen’s biosynthetic proteins based on known loci, indicative of a possible evolutionary convergent acquisition of PNAG synthesis with potential important significance for microbial biology.
Crystal structure of the FRP and identification of the active site for modulation of OCP-mediated photoprotection in cyanobacteria
Authors: Sutter Markus , Wilson Adjélé , Leverenz Ryan L. , Lopez-Igual Rocio , Thurotte Adrien , Salmeen Annette E. , Kirilovsky Diana , Kerfeld Cheryl A.
Published: May 2013

Photosynthetic reaction centers are sensitive to high light conditions, which can cause damage because of the formation of reactive oxygen species. To prevent high-light induced damage, cyanobacteria have developed photoprotective mechanisms. One involves a photoactive carotenoid protein that decreases the transfer of excess energy to the reaction centers. This protein, the orange carotenoid protein (OCP), is present in most cyanobacterial strains; it is activated by high light conditions and able to dissipate excess energy at the site of the light-harvesting antennae, the phycobilisomes. Restoration of normal antenna capacity involves the fluorescence recovery protein (FRP). The FRP acts to dissociate the OCP from the phycobilisomes by accelerating the conversion of the active red OCP to the inactive orange form. We have determined the 3D crystal structure of the FRP at 2.5 Å resolution. Remarkably, the FRP is found in two very different conformational and oligomeric states in the same crystal. Based on amino acid conservation analysis, activity assays of FRP mutants, FRP:OCP docking simulations, and coimmunoprecipitation experiments, we conclude that the dimer is the active form. The second form, a tetramer, may be an inactive form of FRP. In addition, we have identified a surface patch of highly conserved residues and shown that those residues are essential to FRP activity.
Eosinophils secrete IL-4 to facilitate liver regeneration
Authors: Goh Y. P. Sharon , Henderson Neil C. , Heredia Jose E. , Red Eagle Alex , Odegaard Justin I. , Lehwald Nadja , Nguyen Khoa D. , Sheppard Dean , Mukundan Lata , Locksley Richard M. , Chawla Ajay
Published: May 2013

The liver is a central organ for the synthesis and storage of nutrients, production of serum proteins and hormones, and breakdown of toxins and metabolites. Because the liver is susceptible to toxin- or pathogen-mediated injury, it maintains a remarkable capacity to regenerate by compensatory growth. Specifically, in response to injury, quiescent hepatocytes enter the cell cycle and undergo DNA replication to promote liver regrowth. Despite the elucidation of a number of regenerative factors, the mechanisms by which liver injury triggers hepatocyte proliferation are incompletely understood. We demonstrate here that eosinophils stimulate liver regeneration after partial hepatectomy and toxin-mediated injury. Liver injury results in rapid recruitment of eosinophils, which secrete IL-4 to promote the proliferation of quiescent hepatocytes. Surprisingly, signaling via the IL-4Rα in macrophages, which have been implicated in tissue repair, is dispensable for hepatocyte proliferation and liver regrowth after injury. Instead, IL-4 exerts its proliferative actions via IL-4Rα in hepatocytes. Our findings thus provide a unique mechanism by which eosinophil-derived IL-4 stimulates hepatocyte proliferation in regenerating liver.
Regeneration of Little Ice Age bryophytes emerging from a polar glacier with implications of totipotency in extreme environments
Authors: La Farge Catherine , Williams Krista H. , England John H.
Published: May 2013

Across the Canadian Arctic Archipelago, widespread ice retreat during the 20th century has sharply accelerated since 2004. In Sverdrup Pass, central Ellesmere Island, rapid glacier retreat is exposing intact plant communities whose radiocarbon dates demonstrate entombment during the Little Ice Age (1550–1850 AD). The exhumed bryophyte assemblages have exceptional structural integrity (i.e., setae, stem structures, leaf hair points) and have remarkable species richness (60 of 144 extant taxa in Sverdrup Pass). Although the populations are often discolored (blackened), some have developed green stem apices or lateral branches suggesting in vivo regrowth. To test their biological viability, Little Ice Age populations emerging from the ice margin were collected for in vitro growth experiments. Our results include a unique successful regeneration of subglacial bryophytes following 400 y of ice entombment. This finding demonstrates the totipotent capacity of bryophytes, the ability of a cell to dedifferentiate into a meristematic state (analogous to stem cells) and develop a new plant. In polar ecosystems, regrowth of bryophyte tissue buried by ice for 400 y significantly expands our understanding of their role in recolonization of polar landscapes (past or present). Regeneration of subglacial bryophytes broadens the concept of Ice Age refugia, traditionally confined to survival of land plants to sites above and beyond glacier margins. Our results emphasize the unrecognized resilience of bryophytes, which are commonly overlooked vis-a-vis their contribution to the establishment, colonization, and maintenance of polar terrestrial ecosystems.
Letm1, the mitochondrial Ca
2+
/H
+
antiporter, is essential for normal glucose metabolism and alters brain function in Wolf–Hirschhorn syndrome
Authors: Jiang Dawei , Zhao Linlin , Clish Clary B. , Clapham David E.
Published: May 2013

Significance

Wolf–Hirschhorn syndrome (WHS), caused by deletions in 4p16.3, was the first recognized subtelomeric deletion syndrome. As with other syndromes of this class, WHS has not yet been subjected to an intensive, systematic analysis using mouse or cellular models. We recently identified leucine zipper-EF-hand containing transmembrane protein 1 (Letm1) as a mitochondrial Ca
2+
/H
+
antiporter, located in the core WHS region. In this study,
Letm1
null mice were generated and characterized. Deletion of
Letm1
disrupts early embryonic development, reduces glucose oxidation and thus particularly affects brain function.
Semi-uniform sub-additive ergodic theorems for discontinuous skew-product transformations
Authors: Zhang Meirong , Zheng Zuohuan , Zhou Zhe
Published: May 2013

In this paper we will establish some semi-uniform ergodic theorems for skew-product transformations with discontinuity from the point of view of topology. The main assumptions are that the discontinuity sets of transformations are neglected in some measure-theoretical sense. The theorems have extended the classical results which have been established for continuous dynamical systems.
A homology plane of general type can have at most a cyclic quotient singularity
Authors: Gurjar R. , Koras M. , Miyanishi M. , Russell P.
Published: May 2013

We show that a homology plane of general type has at worst a single cyclic quotient singular point. An example of such a surface with a singular point does exist. We also show that the automorphism group of a smooth contractible surface of general type is cyclic.
A method for finding consensus breakpoints in the cancer genome from copy number data
Authors: Toloşi Laura , Theißen Jessica , Halachev Konstantin , Hero Barbara , Berthold Frank , Lengauer Thomas
Published: May 2013

Motivation: Recurrent DNA breakpoints in cancer genomes indicate the presence of critical functional elements for tumor development. Identifying them can help determine new therapeutic targets. High-dimensional DNA microarray experiments like arrayCGH afford the identification of DNA copy number breakpoints with high precision, offering a solid basis for computational estimation of recurrent breakpoint locations.

Results: We introduce a method for identification of recurrent breakpoints (consensus breakpoints) from copy number aberration datasets. The method is based on weighted kernel counting of breakpoints around genomic locations. Counts larger than expected by chance are considered significant. We show that the consensus breakpoints facilitate consensus segmentation of the samples. We apply our method to three arrayCGH datasets and show that by using consensus segmentation we achieve significant dimension reduction, which is useful for the task of prediction of tumor phenotype based on copy number data. We use our approach for classification of neuroblastoma tumors from different age groups and confirm the recent recommendation for the choice of age cut-off for differential treatment of 18 months. We also investigate the (epi)genetic properties at consensus breakpoint locations for seven datasets and show enrichment in overlap with important functional genomic regions.

Availability: Implementation in R of our approach can be found at http://www.mpi-inf.mpg.de/ ∼laura/FeatureGrouping.html.

Contact:  laura@mpi-inf.mpg.de.

Supplementary information:  Supplementary data are available at Bioinformatics online.
First Report of Leaf Spot Disease Caused by Glomerella magna on Lobelia chinensis in China
Authors: Li Q. L. , Mo J. Y. , Huang S. P. , Guo T. X. , Pan Z. B. , Ning P. , Hsiang T.
Published: May 2013

Lobelia chinensis is a perennial herbaceous plant in the family Campanulaceae that is native to China, where it grows well in moist to wet soils. It is commonly used as a Chinese herbal medicine. In May 2012, symptoms of leaf spot were observed on leaves of L. chinensis in Nanning, Guangxi Zhuang Autonomous Region, China. The leaf lesions began as small, water-soaked, pale greenish to grayish spots, which enlarged to gray to pale yellowish spots, 4 to 6 mm in diameter. At later stages, numerous acervuli appeared on the lesions. Acervuli were mostly epiphyllous, and 40 to 196 μm in diameter. On potato dextrose agar (PDA), a fungus was consistently recovered from symptomatic leaf samples, with a 93% isolation rate from 60 leaf pieces that were surface sterilized in 75% ethanol for 30 s and then in 0.1% mercuric chloride for 45 s. Three single-spore isolates were used to evaluate cultural and morphological characteristics of the pathogen. Setae were two to three septate, dark brown at the base, acicular, and up to 90 μm long. Conidia were long oblong-elliptical, guttulate, hyaline, and 11 to 20 × 4.1 to 6.3 μm (mean 15.2 × 5.1 μm). These morphological characteristics of the fungus were consistent with the description of Colletotrichum magna (teleomorph Glomerella magna Jenkins & Winstead) (1). The rDNA internal transcribed spacer (ITS) region of one isolate, LC-1, was sequenced (GenBank Accession No. KC815123), and it showed 100% identity to G. magna, GenBank HM163187.1, an isolate from Brazil cultured from papaya (2). Although KC815123 was identified as G. magna, it shows 99% identity to GenBank sequences from isolates of C. magna, and more research is needed to elucidate the relationships between these taxa, especially with consideration to host specificity. Pathogenicity tests were performed with each of the three isolates by spraying conidial suspensions (1 × 106 conidia/ml) containing 0.1% Tween 20 onto the surfaces of leaves of 30-day-old and 6- to 8-cm-high plants. For each isolate, 30 leaves from five replicate plants were treated. Control plants were treated with sterilized water containing 0.1% Tween 20. All plants were incubated for 36 h at 25°C and 90% relative humidity in an artificial climate chamber, and then moved into a greenhouse. Seven days after inoculation, gray spots typical of field symptoms were observed on all inoculated leaves, but no symptoms were seen on water-treated control plants. Koch's postulates were fulfilled by reisolation of G. magna from diseased leaves. To our knowledge, this is the first report of G. magna infecting L. chinensis worldwide.

References: (1) M. Z. Du et al. Mycologia 97:641, 2005. (2) R. J. Nascimento et al. Plant Dis. 94:1506, 2010.
First Report of ‘Candidatus Phytoplasma solani’ Strains Associated with Grapevine Bois Noir in Jordan
Authors: Salem N. M. , Quaglino F. , Abdeen A. , Casati P. , Bulgari D. , Alma A. , Bianco P. A.
Published: May 2013

During a survey carried out in Jordanian vineyards in August and October 2012, grapevine (Vitis vinifera L.) plants showing typical grapevine yellows (GY) disease symptoms, including leaf discoloration and curling, berry shriveling, and irregular maturation of wood, were observed. In the same vineyards, bindweed (Convolvulus arvensis L.) plants showing stunting and leaf chromatic alteration were found, suggesting the involvement of phytoplasmas in the disease etiology. Using a CTAB method, total DNA was extracted from leaf veins of 25 symptomatic and two asymptomatic grapevines, and from five symptomatic and two asymptomatic bindweeds for PCR analysis. DNAs from periwinkle (Catharanthus roseus (L.) G. Don) plants infected by ‘Ca. Phytoplasma asteris’ strain SAY (group 16SrI), ‘Ca. Phytoplasma solani’ strain STOL (group 16SrXII), and ‘Ca. Phytoplasma ulmi’ strain EY1 (group 16SrV), were used as positive controls. DNAs from healthy periwinkle and reactions without template DNA were employed as negative controls. 16S rDNA nested PCRs, carried out using the primer pairs P1/P7, followed by R16F2n/R16R2 (1), yielded an amplicon of the expected size (1,250-bp) in three grapevine and in five bindweed samples, and in positive controls. Amplicons were not produced with DNA from 22 symptomatic grapevines (probably because samples were collected late in the growing season and phytoplasma distribution in plants was non-uniform [2]); nor from asymptomatic plants and negative controls. PCR products were sequenced by commercial services in Italy (Primm, Milan) and Korea (Macrogen Inc., Soul). Representative 16S rDNA nucleotide sequences were deposited in NCBI GenBank with accessions KC835139 (from grapevine) and KC835140 (from bindweed). The 16S rDNA nucleotide sequences of phytoplasmas identified in grapevine and bindweed in Jordan shared >99.5% sequence identity with ‘Ca. Phytoplasma solani’ reference strain STOL (AF248959), and carried identical STOL-unique signature sequences and distinguishing sequence blocks (3). Phylogenetic and in silico RFLP analyses confirmed the affiliation of phytoplasma strains identified in grapevine and bindweed in Jordan to the species ‘Ca. Phytoplasma solani’ (subgroup 16SrXII-A), opening an avenue to future studies on the dissemination and impact of Bois noir (BN) in Jordan. These studies may add new information about BN, previously reported in neighboring countries (4). Further studies will investigate the role of Hyalesthes obsoletus Signoret, a polyphagous Cixiidae responsible for the BN phytoplasma transmission in Europe, and other possible insect vector(s) in the BN spread in Jordan.

References: (1) I.-M. Lee et al. Int. J. Syst. Bact. 48:1153, 1998. (2) F. E. Constable et al. Plant Pathol. 52:267, 2003. (3) F. Quaglino et al. Int. J. Syst. Evol. Microb. 63:2879. (4) E. Choueiri et al. Plant Dis. 86:697, 2002.
Spatial Pattern of Strawberry Powdery Mildew (Podosphaera aphanis) and Airborne Inoculum
Authors: Van der Heyden H. , Lefebvre M. , Roberge L. , Brodeur L. , Carisse O.
Published: May 2013

The relationship between strawberry powdery mildew and airborne conidium concentration (ACC) of Podosphaera aphanis was studied using data collected from 2006 to 2009 in 15 fields, and spatial pattern was described using 2 years of airborne inoculum and disease incidence data collected in fields planted with the June-bearing strawberry (Fragaria × ananassa) cultivar Jewel. Disease incidence, expressed as the proportion of diseased leaflets, and ACC were monitored in fields divided into 3 × 8 grids containing 24 100 m2 quadrats. Variance-to-mean ratio, index of dispersion, negative binomial distribution, Poisson distribution, and binomial and beta-binomial distributions were used to characterize the level of spatial heterogeneity. The relationship between percent leaf area diseased and daily ACC was linear, while the relationship between ACC and disease incidence followed an exponential growth curve. The V/M ratios were significantly greater than 1 for 100 and 96% of the sampling dates for ACC sampled at 0.35 m from the ground (ACC0.35m) and for ACC sampled at 1.0 m from the ground (ACC1.0m), respectively. For disease incidence, the index of dispersion D was significantly greater than 1 for 79% of the sampling dates. The negative binomial distribution fitted 86% of the data sets for both ACC1.0m and ACC0.35m. For disease incidence data, the beta-binomial distribution provided a good fit of 75% of the data sets. Taylor's power law indicated that, for ACC at both sampling heights, heterogeneity increased with increasing mean ACC, whereas the binary form of the power law suggested that heterogeneity was not dependent on the mean for disease incidence. When the spatial location of each sampling location was taken into account, Spatial Analysis by Distance Indices showed low aggregation indices for both ACCs and disease incidence, and weak association between ACC and disease incidence. Based on these analyses, it was found that the distribution of strawberry powdery mildew was weakly aggregated. Although a higher level of heterogeneity was observed for airborne inoculum, the heterogeneity was low with no distinct foci, suggesting that epidemics are induced by well-distributed inoculum. This low level of heterogeneity allows mean airborne inoculum concentration to be estimated using only one sampler per field with an overall accuracy of at least 0.841. The results obtained in this study could be used to develop a sampling scheme that will improve strawberry powdery mildew risk estimation.
First Report of Sweet potato leaf curl Georgia virus on Sweet Potato in China
Authors: Qin Y. , Zhang Z. , Qiao Z. , Qiao Q. , Zhang D. , Tian Y. , Wang S.
Published: May 2013

Begomoviruses infecting sweet potato (Ipomoea batatas) are phylogenetically distinct from other members of the genus Begomovirus, and have been named “sweepoviruses” (1). Sweepoviruses cause sweet potato yield losses and cultivar decline, and have been found in China (1,3). In 2011, a survey was conducted to determine the incidence, genetic diversity, and distribution of sweepoviruses in China. Thirty sweet potato cuttings showing upward leaf curl, leaf roll, chlorosis, and stunting were collected from fields in Jiangsu, Guangxi, Guizhou, Shanxi, Henan, and Hebei Provinces. Five-leaf growth stage I. setosa plants were inoculated by side-grafting with scions from these samples, and grown in an insect-proof greenhouse in 20-cm-diameter clay pots. Each sample was grafted onto three replicate plants. Healthy, non-grafted I. setosa plants were used as the negative control treatment. Total nucleic acids were extracted from 100 mg fresh leaves harvested 30 days post-inoculation (dpi) from symptomatic and negative control plants using the Universal Genomic DNA Extraction Kit (TaKaRa, Dalian, China). Universal primers for amplification of Geminiviruses (BM-V [5′-KSGGGTCGACGTCATCAATGACGTTRTAC-3′] and BM-C [5′-AARGAATTCATKGGGGCCCARARRGACTGGC-3′]) (2) were used to amplify the begomovirus A component by PCR assay. A DNA fragment of the expected size (2.8 kb) was obtained from grafted leaf samples of the Hebei Province plant, and was cloned into the pMD-19T vector (TaKaRa). The recombinant plasmid was transformed into competent cells of Escherichia coli strain JM109, and the inserted fragment sequenced. The nucleotide sequence obtained (GenBank Accession No. JX448368) was 2,785 nt long, and contained two open reading frames (ORFs) in the virion sense, and four ORFs in the complementary sense, similar to other monopartite begomoviruses (1). The sequence was compared with sequences in GenBank using BLAST. The results revealed the greatest nucleotide sequence identity, 90.8%, with that of the Sweet potato leaf curl Georgia virus (SPLCGV) from Georgia, United States (AF326775). The sequence also shared identities of <89% with other sweepoviruses, and was therefore designated SPLCGV-China: Hebei: 2011. Comparison of the complete genome sequence of SPLCGV-China: Hebei: 2011 with SPLCGV revealed an 18 nucleotide insertion between AV-1 and AC-3. The results confirmed that the sweet potato sample from which SPLCGV-China: Hebei: 2011 was obtained was infected with SPLCGV. To our knowledge, this is the first report of the natural occurrence of SPLCGV in China. This study will assist with understanding the presence of this virus and genetic diversity of sweepoviruses in China.

References: (1) H. P. Bi and P. Zhang. Arch. Virol. 157:441, 2012. (2) R. W. Briddon and P. G. Markham. Mol. Biotechnol. 1:202, 1994. (3) Y. S. Luan et al. Virus Genes 35:379, 2007.
Fine Mapping and Identification of Blast Resistance Gene Pi-hk1 in a Broad-Spectrum Resistant japonica Rice Landrace
Authors: Wu Yunyu , Bao Yongmei , Xie Liujie , Su Yunyun , Chu Ruizhen , He Wanwan , Huang Ji , Wang Jianfei , Zhang Hongsheng
Published: May 2013

One Japonica rice landrace, Heikezijing, from the Taihu Lake region of China, exhibits broad-spectrum resistance to rice blast. As characterized in our previous research, a main-effect resistance (R) gene, Pi-hk1, in Heikezijing against five isolates (GD10-279a, JS2004-141-1, JS2004-185, JS90-78, and Hoku1) was roughly mapped on the long arm of chromosome 11. To fine map Pi-hk1, one recombinant inbred line (RIL), RIL72 (F2:8), from the cross between Heikezijing and blast-susceptible variety Suyunuo, was further crossed and backcrossed with Suyunuo to produce a BC1F2 population of 477 individuals. Inoculation experiments with the representative isolate Hoku 1 indicated that RIL72 carries a single dominant R gene for blast resistance. With the help of advanced BC1F3 (915 plants), BC1F4 (4,459 plants), and BC1F5 (2,000 plants) mapping populations, Pi-hk1 was finally mapped to a 107-kb region between molecular markers P3586 and ILP3, and co-segregated with the markers P4098, RM7654, and P4099. By sequence analysis of Heikezijing bacterial artificial chromosome clones covering Pi-hk1 region, 16 predicted genes were identified within this region, including three nucleotide-binding site leucine-rich repeat candidate genes. These results provide essential information for cloning of Pi-hk1 and its application in rice breeding for broad-spectrum blast resistance by marker-assisted selection.
Potential of DNA Barcoding for Detecting Quarantine Fungi
Authors: Gao Ruifang , Zhang Guiming
Published: May 2013

The detection of live quarantine pathogenic fungi plays an important role in guaranteeing regional biological safety. DNA barcoding, an emerging species identification technology, holds promise for the reliable, quick, and accurate detection of quarantine fungi. International standards for phytosanitary guidelines are urgently needed. The varieties of quarantine fungi listed for seven countries/regions, the currently applied detection methods, and the status of DNA barcoding for detecting quarantine fungi are summarized in this study. Two approaches have been proposed to apply DNA barcoding to fungal quarantine procedures: (i) to verify the reliability of known internal transcribed spacer (ITS)/cytochrome c oxidase subunit I (COI) data for use as barcodes, and (ii) to determine other barcodes for species that cannot be identified by ITS/COI. As a unique, standardizable, and universal species identification tool, DNA barcoding offers great potential for integrating detection methods used in various countries/regions and establishing international detection standards based on accepted DNA barcodes. Through international collaboration, interstate disputes can be eased and many problems related to routine quarantine detection methods can be solved for global trade.
Pathophysiology of white-nose syndrome in bats: a mechanistic model linking wing damage to mortality
Authors: Warnecke Lisa , Turner James M. , Bollinger Trent K. , Misra Vikram , Cryan Paul M. , Blehert David S. , Wibbelt Gudrun , Willis Craig K. R.
Published: May 2013

White-nose syndrome is devastating North American bat populations but we lack basic information on disease mechanisms. Altered blood physiology owing to epidermal invasion by the fungal pathogen
Geomyces destructans
(
Gd
) has been hypothesized as a cause of disrupted torpor patterns of affected hibernating bats, leading to mortality. Here, we present data on blood electrolyte concentration, haematology and acid–base balance of hibernating little brown bats,
Myotis lucifugus
, following experimental inoculation with
Gd
. Compared with controls, infected bats showed electrolyte depletion (i.e. lower plasma sodium), changes in haematology (i.e. increased haematocrit and decreased glucose) and disrupted acid–base balance (i.e. lower CO
2
partial pressure and bicarbonate). These findings indicate hypotonic dehydration, hypovolaemia and metabolic acidosis. We propose a mechanistic model linking tissue damage to altered homeostasis and morbidity/mortality.
The relationship between virtual body ownership and temperature sensitivity
Authors: Llobera Joan , Sanchez-Vives M. V. , Slater Mel
Published: May 2013

In the rubber hand illusion, tactile stimulation seen on a rubber hand, that is synchronous with tactile stimulation felt on the hidden real hand, can lead to an illusion of ownership over the rubber hand. This illusion has been shown to produce a temperature decrease in the hidden hand, suggesting that such illusory ownership produces disownership of the real hand. Here, we apply immersive virtual reality (VR) to experimentally investigate this with respect to sensitivity to temperature change. Forty participants experienced immersion in a VR with a virtual body (VB) seen from a first-person perspective. For half the participants, the VB was consistent in posture and movement with their own body, and in the other half, there was inconsistency. Temperature sensitivity on the palm of the hand was measured before and during the virtual experience. The results show that temperature sensitivity decreased in the consistent compared with the inconsistent condition. Moreover, the change in sensitivity was significantly correlated with the subjective illusion of virtual arm ownership but modulated by the illusion of ownership over the full VB. This suggests that a full body ownership illusion results in a unification of the virtual and real bodies into one overall entity—with proprioception and tactile sensations on the real body integrated with the visual presence of the VB. The results are interpreted in the framework of a ‘body matrix’ recently introduced into the literature.
Impact of plant shoot architecture on leaf cooling: a coupled heat and mass transfer model
Authors: Bridge L. J. , Franklin K. A. , Homer M. E.
Published: May 2013

Plants display a range of striking architectural adaptations when grown at elevated temperatures. In the model plant
Arabidopsis thaliana
, these include elongation of petioles, and increased petiole and leaf angles from the soil surface. The potential physiological significance of these architectural changes remains speculative. We address this issue computationally by formulating a mathematical model and performing numerical simulations, testing the hypothesis that elongated and elevated plant configurations may reflect a leaf-cooling strategy. This sets in place a new basic model of plant water use and interaction with the surrounding air, which couples heat and mass transfer within a plant to water vapour diffusion in the air, using a transpiration term that depends on saturation, temperature and vapour concentration. A two-dimensional, multi-petiole shoot geometry is considered, with added leaf-blade shape detail. Our simulations show that increased petiole length and angle generally result in enhanced transpiration rates and reduced leaf temperatures in well-watered conditions. Furthermore, our computations also reveal plant configurations for which elongation may result in decreased transpiration rate owing to decreased leaf liquid saturation. We offer further qualitative and quantitative insights into the role of architectural parameters as key determinants of leaf-cooling capacity.
Lister at home and abroad: a continuing legacy
Authors: Crowther M. Anne
Published: May 2013

Joseph Lister's painstaking experiments in antiseptic lotions, dressings, and sutures in the 1860s and early 1870s seemed needlessly complex to his critics and were best understood by those who saw him in action. From the 1880s the acrimony subsided, and Lister's international reputation became a major asset to the medical profession, even as it discarded or bypassed many of his techniques. He was claimed as an influence by many new specialties, even though in some cases his links with the discipline were tenuous. By the early twentieth century Lister had become a focus of imperial sentiment, and his legacy is seen at home and abroad through successive generations of students from his Scottish universities.
Homogenization for deterministic maps and multiplicative noise
Authors: Gottwald Georg A. , Melbourne Ian
Published: May 2013

A recent paper of Melbourne & Stuart (2011 A note on diffusion limits of chaotic skew product flows.
Nonlinearity
24
, 1361–1367 (doi:10.1088/0951-7715/24/4/018)) gives a rigorous proof of convergence of a fast–slow deterministic system to a stochastic differential equation with additive noise. In contrast to other approaches, the assumptions on the fast flow are very mild. In this paper, we extend this result from continuous time to discrete time. Moreover, we show how to deal with one-dimensional multiplicative noise. This raises the issue of how to interpret certain stochastic integrals; it is proved that the integrals are of Stratonovich type for continuous time and neither Stratonovich nor Itô for discrete time. We also provide a rigorous derivation of super-diffusive limits where the stochastic differential equation is driven by a stable Lévy process. In the case of one-dimensional multiplicative noise, the stochastic integrals are of Marcus type both in the discrete and continuous time contexts.
Evolution mediates the effects of apex predation on aquatic food webs
Authors: Urban Mark C.
Published: May 2013

Ecological and evolutionary mechanisms are increasingly thought to shape local community dynamics. Here, I evaluate if the local adaptation of a meso-predator to an apex predator alters local food webs. The marbled salamander (
Ambystoma opacum
) is an apex predator that consumes both the spotted salamander (
Ambystoma maculatum
) and shared zooplankton prey. Common garden experiments reveal that spotted salamander populations which co-occur with marbled salamanders forage more intensely than those that face other predator species. These foraging differences, in turn, alter the diversity, abundance and composition of zooplankton communities in common garden experiments and natural ponds. Locally adapted spotted salamanders exacerbate prey biomass declines associated with apex predation, but dampen the top-down effects of apex predation on prey diversity. Countergradient selection on foraging explains why locally adapted spotted salamanders exacerbate prey biomass declines. The two salamander species prefer different prey species, which explains why adapted spotted salamanders buffer changes in prey composition owing to apex predation. Results suggest that local adaptation can strongly mediate effects from apex predation on local food webs. Community ecologists might often need to consider the evolutionary history of populations to understand local diversity patterns, food web dynamics, resource gradients and their responses to disturbance.
Hybridization between genetically modified Atlantic salmon and wild brown trout reveals novel ecological interactions
Authors: Oke Krista B. , Westley Peter A. H. , Moreau Darek T. R. , Fleming Ian A.
Published: May 2013

Interspecific hybridization is a route for transgenes from genetically modified (GM) animals to invade wild populations, yet the ecological effects and potential risks that may emerge from such hybridization are unknown. Through experimental crosses, we demonstrate transmission of a growth hormone transgene via hybridization between a candidate for commercial aquaculture production, GM Atlantic salmon (
Salmo salar
) and closely related wild brown trout (
Salmo trutta
). Transgenic hybrids were viable and grew more rapidly than transgenic salmon and other non-transgenic crosses in hatchery-like conditions. In stream mesocosms designed to more closely emulate natural conditions, transgenic hybrids appeared to express competitive dominance and suppressed the growth of transgenic and non-transgenic (wild-type) salmon by 82 and 54 per cent, respectively. To the best of our knowledge, this is the first demonstration of environmental impacts of hybridization between a GM animal and a closely related species. These results provide empirical evidence of the first steps towards introgression of foreign transgenes into the genomes of new species and contribute to the growing evidence that transgenic animals have complex and context-specific interactions with wild populations. We suggest that interspecific hybridization be explicitly considered when assessing the environmental consequences should transgenic animals escape to nature.
Soft X-ray absorption spectroscopy and resonant inelastic X-ray scattering spectroscopy below 100 eV: probing first-row transition-metalM-edges in chemical complexes
Authors: Wang Hongxin , Young Anthony T. , Guo Jinghua , Cramer Stephen P. , Friedrich Stephan , Braun Artur , Gu Weiwei
Published: May 2013

X-ray absorption and scattering spectroscopies involving the 3dtransition-metalK- andL-edges have a long history in studying inorganic and bioinorganic molecules. However, there have been very few studies using theM-edges, which are below 100 eV. Synchrotron-based X-ray sources can have higher energy resolution atM-edges.M-edge X-ray absorption spectroscopy (XAS) and resonant inelastic X-ray scattering (RIXS) could therefore provide complementary information toK- andL-edge spectroscopies. In this study,M2,3-edge XAS on several Co, Ni and Cu complexes are measured and their spectral information, such as chemical shifts and covalency effects, are analyzed and discussed. In addition,M2,3-edge RIXS on NiO, NiF2and two other covalent complexes have been performed and differentd–dtransition patterns have been observed. Although still preliminary, this work on 3dmetal complexes demonstrates the potential to useM-edge XAS and RIXS on more complicated 3dmetal complexes in the future. The potential for using high-sensitivity and high-resolution superconducting tunnel junction X-ray detectors below 100 eV is also illustrated and discussed.
Towards tacit knowledge sharing over social web tools
Authors: Panahi Sirous , Watson Jason , Partridge Helen
Published: May 2013

Purpose

Researchers debate whether tacit knowledge sharing through information technology (IT) is actually possible. However, with the advent of social web tools, it has been argued that most shortcomings of tacit knowledge sharing are likely to disappear. The purpose of this paper is two‐fold: first, to demonstrate the existing debates in the literature regarding tacit knowledge sharing using IT; and second, to identify key research gaps that lay the foundations for future research into tacit knowledge sharing using the social web.

Design/methodology/approach

This paper reviews current literature on IT‐mediated tacit knowledge sharing and opens a discussion on tacit knowledge sharing through the use of the social web.

Findings

First, the existing schools of thought in regards to IT ability for tacit knowledge sharing are introduced. Next, difficulties of sharing tacit knowledge through the use of IT are discussed. Then, potentials and pitfalls of social web tools are presented. Finally, the paper concludes that whilst there are significant theoretical arguments supporting the notion that the social web facilitates tacit knowledge sharing there is a lack of empirical evidence to support these arguments and further work is required.

Research limitations/implications

The limitations of the review include: covering only papers that were published in English, issues of access to full texts of some resources, and the possibility of missing some resources due to search strings used or limited coverage of databases searched.

Originality/value

The paper contributes to the fast growing literature on the intersection of KM and IT particularly by focusing on tacit knowledge sharing in social media space. The paper highlights the need for further studies in this area by discussing the current situation in the literature and disclosing the emerging questions and gaps for future studies.
Study on enterprise knowledge sharing in ESN perspective: a Chinese case study
Authors: Zhao Rong‐ying , Chen Bi‐kun
Published: May 2013

Purpose

An enterprise social network (ESN) is part of the landscape of information reform by enterprises, using Web 2.0. In terms of the marketing targets of typical Web 2.0 techniques, enterprise knowledge sharing in Web 2.0 can be classified into different types (individual interaction type, group interaction type, social interaction type, real‐time interaction type and delay interaction type). The purpose of this paper is to summarize the features and modes of different enterprises' knowledge sharing and study enterprise knowledge sharing quantitatively from an ESN perspective by selecting real‐time interaction type as the case.

Design/methodology/approach

Because of the area of research, the authors supplemented social network analysis (SNA) with a mathematical modeling method and additional in‐depth interviews.

Findings

The Web 2.0 era provides the opportunity to quantify knowledge sharing. Also, SNA can quantitatively and visually diagnose the knowledge sharing status of the enterprise and guide the enterprise's knowledge‐sharing process.

Research limitations/implications

Only a case study regarding real‐time interaction type is presented; other types of interaction are not studied empirically.

Practical implications

SNA, combined with a mathematical modeling method and additional in‐depth interviews with team leaders or key managers in organizations, can diagnose quantitatively, visually and comprehensively the knowledge‐sharing status of the enterprise.

Originality/value

This paper systematically summarizes the features and modes of Web 2.0 enterprise knowledge sharing, and the multiple‐method research design represents a sound approach to targeting enterprise knowledge sharing.
The biomechanical basis of evolutionary change in a territorial display
Authors: Ord Terry J. , Collar David C. , Sanger Thomas J.
Published: May 2013

Few studies have examined how the anatomy of an animal signal contributes to, or limits, the evolution of signal differentiation among closely related species.

InAnolislizards, adult males extend a large, conspicuous dewlap as part of a territorial advertisement display. Males of species from the island of Jamaica rely on the rapid extension of the dewlap to facilitate display detection by territorial neighbours and conspecific females. Males of other species on the island of Puerto Rico extend the dewlap at considerably slower speeds and instead rely on other strategies to maintain an effective display. What initially prompted this divergence in display between the islands is unknown, but evidence suggests that it may have something to do with the way the dewlap is extended during display.

Our goal was to determine whether an innovation in the dewlap lever in Jamaican lineages, but absent in Puerto Rican lineages, accounted for the evolution of the high‐speed dewlap on Jamaica. We began by modelling the performance of theAnolisdewlap as a first‐order lever system. We then simulated changes to this system relating to its morphology, articulation and input force in biologically realistic ways to predict how such changes impact dewlap speed. Finally, we compared these predictions with data on the morphology of the dewlap lever system from museum specimens and actual dewlap speed recorded for lizards in the field.

This investigation revealed that changes to the dewlap lever have affected the performance of the dewlap display in at least two ways. Within islands, structural changes to the hyoid morphology seem to have led to differences in dewlap speed among species. Between islands, however, differences in dewlap speed were most likely the result of a major increase in muscle contraction velocity that powers the dewlap extension in Jamaican species, but has not originated in species on Puerto Rico.

Our study shows how the biomechanics of a social signal can have important implications for understanding why closely related species might differ in signal behaviour, despite apparent similarities in the selection pressures that act on the signal.