WorldWideScience

Sample records for invading short pnas

  1. Self-assembling, dynamic alphaPNAs

    DEFF Research Database (Denmark)

    Nielsen, Peter E

    2009-01-01

    In the recent report published in Science, Ghadiri and coworkers describe dynamic tPNAs, alphaPNA derivatives with a nucleobase attached via a thioester bond that are a step forward toward self-repairing and replicating molecules.......In the recent report published in Science, Ghadiri and coworkers describe dynamic tPNAs, alphaPNA derivatives with a nucleobase attached via a thioester bond that are a step forward toward self-repairing and replicating molecules....

  2. (α,α-dimethyl)glycyl (dmg) PNAs

    Science.gov (United States)

    Gourishankar, Aland; Ganesh, Krishna N.

    2012-01-01

    The design and facile synthesis of sterically constrained new analogs of PNA having gem-dimethyl substitutions on glycine (dmg-PNA-T) is presented. The PNA oligomers [aminoethyl dimethylglycyl (aedmg) and aminopropyl dimethylglycyl (apdmg)] synthesized from the monomers 6 and 12) effected remarkable stabilization of homothyminePNA2:homoadenine DNA/RNA triplexes and mixed base sequence duplexes with target cDNA or RNA. They show a higher binding to DNA relative to that with isosequential RNA. This may be a structural consequence of the sterically rigid gem-dimethyl group, imposing a pre-organized conformation favorable for complex formation with cDNA. The results complement our previous work that had demonstrated that cyclohexanyl-PNAs favor binding with cRNA compared with cDNA and imply that the biophysical and structural properties of PNAs can be directed by introduction of the right rigidity in PNA backbone devoid of chirality. This approach of tweaking selectivity in binding of PNA constructs by installing gem-dimethyl substitution in PNA backbone can be extended to further fine-tuning by similar substitution in the aminoethyl segment as well either individually or in conjunction with present substitution. PMID:22679528

  3. Expression of hPNAS-4 Radiosensitizes Lewis Lung Cancer

    International Nuclear Information System (INIS)

    Zeng Hui; Yuan Zhu; Zhu Hong; Li Lei; Shi Huashan; Wang Zi; Fan Yu; Deng Qian; Zeng Jianshuang; He Yinbo; Xiao Jianghong; Li Zhiping

    2012-01-01

    Purpose: This study aimed to transfer the hPNAS-4 gene, a novel apoptosis-related human gene, into Lewis lung cancer (LL2) and observe its radiosensitive effect on radiation therapy in vitro and in vivo. Methods and Materials: The hPNAS-4 gene was transfected into LL2 cells, and its expression was detected via western blot. Colony formation assay and flow cytometry were used to detect the growth and apoptosis of cells treated with irradiation/PNAS-4 in vitro. The hPNAS-4 gene was transferred into LL2-bearing mice through tail vein injection of the liposome/gene complex. The tumor volumes were recorded after radiation therapy. Proliferating cell nuclear antigen (PCNA) immunohistochemistry staining and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay were performed to detect the tumor cell growth and apoptosis in vivo. Results: The hPNAS-4 gene was successfully transferred into LL2 cells and tumor tissue, and its overexpressions were confirmed via western blot analysis. Compared with the control, empty plasmid, hPNAS-4, radiation, and empty plasmid plus radiation groups, the hPNAS-4 plus radiation group more significantly inhibited growth and enhanced apoptosis of LL2 cells in vitro and in vivo (P<.05). Conclusions: The hPNAS-4 gene was successfully transferred into LL2 cells and tumor tissue and was expressed in both LL2 cell and tumor tissue. The hPNAS-4 gene therapy significantly enhanced growth inhibition and apoptosis of LL2 tumor cells by radiation therapy in vitro and in vivo. Therefore, it may be a potential radiosensitive treatment of radiation therapy for lung cancer.

  4. A BACTERIAL CYTOKINE Mukamolova et al (1998) PNAS, 95, 8916 ...

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. A BACTERIAL CYTOKINE Mukamolova et al (1998) PNAS, 95, 8916-8921. To grow or not to grow is a social decision. A resuscitation promoting factor (rpf) identified. The rpf protein shares similarity with M. tuberculosis and M. leprae ...

  5. Solid-Phase Synthesis of Difficult Purine-Rich PNAs through Selective Hmb Incorporation: Application to the Total Synthesis of Cell Penetrating Peptide-PNAs

    Directory of Open Access Journals (Sweden)

    Julien Tailhades

    2017-10-01

    Full Text Available Antisense oligonucleotide (ASO-based drug development is gaining significant momentum following the recent FDA approval of Eteplirsen (an ASO based on phosphorodiamidate morpholino and Spinraza (2′-O-methoxyethyl-phosphorothioate in late 2016. Their attractiveness is mainly due to the backbone modifications which have improved the in vivo characteristics of oligonucleotide drugs. Another class of ASO, based on peptide nucleic acid (PNA chemistry, is also gaining popularity as a platform for development of gene-specific therapy for various disorders. However, the chemical synthesis of long PNAs, which are more target-specific, remains an ongoing challenge. Most of the reported methodology for the solid-phase synthesis of PNA suffer from poor coupling efficiency which limits production to short PNA sequences of less than 15 residues. Here, we have studied the effect of backbone modifications with Hmb (2-hydroxy-4-methoxybenzyl and Dmb (2,4-dimethoxybenzyl to ameliorate difficult couplings and reduce “on-resin” aggregation. We firstly synthesized a library of PNA dimers incorporating either Hmb or Dmb and identified that Hmb is superior to Dmb in terms of its ease of removal. Subsequently, we used Hmb backbone modification to synthesize a 22-mer purine-rich PNA, targeting dystrophin RNA splicing, which could not be synthesized by standard coupling methodology. Hmb backbone modification allowed this difficult PNA to be synthesized as well as to be continued to include a cell-penetrating peptide on the same solid support. This approach provides a novel and straightforward strategy for facile solid-phase synthesis of difficult purine-rich PNA sequences.

  6. Solid-phase synthesis of difficult purine-rich PNAs through selective Hmb incorporation: Application to the total synthesis of cell penetrating peptide-PNAs

    Science.gov (United States)

    Tailhades, Julien; Takizawa, Hotake; Gait, Michael J.; Wellings, Don A.; Wade, John D.; Aoki, Yoshitsugu; Shabanpoor, Fazel

    2017-10-01

    Antisense oligonucleotide (ASO)-based drug development is gaining significant momentum following the recent FDA approval of Eteplirsen (an ASO based on phosphorodiamidate morpholino) and Spinraza (2’-O-methoxyethyl-phosphorothioate) in late 2016. Their attractiveness is mainly due to the backbone modifications which have improved the in vivo characteristics of oligonucleotide drugs. Another class of ASO, based on peptide nucleic acid (PNA) chemistry, is also gaining popularity as a platform for development of gene-specific therapy for various disorders. However, the chemical synthesis of long PNAs, which are more target-specific, remains an ongoing challenge. Most of the reported methodology for the solid-phase synthesis of PNA suffer from poor coupling efficiency which limits production to short PNA sequences of less than 15 residues. Here we have studied the effect of backbone modifications with Hmb (2-hydroxy-4-methoxybenzyl) and Dmb (2,4-dimethoxybenzyl) to ameliorate difficult couplings and reduce “on-resin” aggregation. We firstly synthesized a library of PNA dimers incorporating either Hmb or Dmb and identified that Hmb is superior to Dmb in terms of its ease of removal. Subsequently, we used Hmb backbone modification to synthesize a 22-mer purine-rich PNA, targeting dystrophin RNA splicing, which could not be synthesized by standard coupling methodology. Hmb backbone modification allowed this difficult PNA to be synthesized as well as to be continued to include a cell-penetrating peptide on the same solid support. This approach provides a novel and straightforward strategy for facile solid-phase synthesis of difficult purine-rich PNA sequences.

  7. Inhibition of HIV Replication by Cyclic and Hairpin PNAs Targeting the HIV-1 TAR RNA Loop

    Science.gov (United States)

    Upert, Gregory; Di Giorgio, Audrey; Upadhyay, Alok; Manvar, Dinesh; Pandey, Nootan; Pandey, Virendra N.; Patino, Nadia

    2012-01-01

    Human immunodeficiency virus-1 (HIV-1) replication and gene expression entails specific interaction of the viral protein Tat with its transactivation responsive element (TAR), to form a highly stable stem-bulge-loop structure. Previously, we described triphenylphosphonium (TPP) cation-based vectors that efficiently deliver nucleotide analogs (PNAs) into the cytoplasm of cells. In particular, we showed that the TPP conjugate of a linear 16-mer PNA targeting the apical stem-loop region of TAR impedes Tat-mediated transactivation of the HIV-1 LTR in vitro and also in cell culture systems. In this communication, we conjugated TPP to cyclic and hairpin PNAs targeting the loop region of HIV-1 TAR and evaluated their antiviral efficacy in a cell culture system. We found that TPP-cyclic PNAs containing only 8 residues, showed higher antiviral potency compared to hairpin PNAs of 12 or 16 residues. We further noted that the TPP-conjugates of the 8-mer cyclic PNA as well as the 16-mer linear PNA displayed similar antiviral efficacy. However, cyclic PNAs were shown to be highly specific to their target sequences. This communication emphasizes on the importance of small constrained cyclic PNAs over both linear and hairpin structures for targeting biologically relevant RNA hairpins. PMID:23029603

  8. Inhibition of HIV Replication by Cyclic and Hairpin PNAs Targeting the HIV-1 TAR RNA Loop

    Directory of Open Access Journals (Sweden)

    Gregory Upert

    2012-01-01

    Full Text Available Human immunodeficiency virus-1 (HIV-1 replication and gene expression entails specific interaction of the viral protein Tat with its transactivation responsive element (TAR, to form a highly stable stem-bulge-loop structure. Previously, we described triphenylphosphonium (TPP cation-based vectors that efficiently deliver nucleotide analogs (PNAs into the cytoplasm of cells. In particular, we showed that the TPP conjugate of a linear 16-mer PNA targeting the apical stem-loop region of TAR impedes Tat-mediated transactivation of the HIV-1 LTR in vitro and also in cell culture systems. In this communication, we conjugated TPP to cyclic and hairpin PNAs targeting the loop region of HIV-1 TAR and evaluated their antiviral efficacy in a cell culture system. We found that TPP-cyclic PNAs containing only 8 residues, showed higher antiviral potency compared to hairpin PNAs of 12 or 16 residues. We further noted that the TPP-conjugates of the 8-mer cyclic PNA as well as the 16-mer linear PNA displayed similar antiviral efficacy. However, cyclic PNAs were shown to be highly specific to their target sequences. This communication emphasizes on the importance of small constrained cyclic PNAs over both linear and hairpin structures for targeting biologically relevant RNA hairpins.

  9. The unseen invaders

    DEFF Research Database (Denmark)

    Craven, Dylan; Thakur, Madhav P.; Cameron, Erin

    2017-01-01

    earthworms on plant diversity and community composition in North American forests. We conducted a meta-analysis using a total of 645 observations to quantify mean effect sizes of associations between introduced earthworm communities and plant diversity, cover of plant functional groups, and cover of native...... to the abiotic conditions of earthworm-invaded forests. Further, our study provides evidence that introduced earthworms are associated with declines in plant diversity in North American forests. Changing plant functional composition in these forests may have long-lasting effects on ecosystem functioning....

  10. Sequence-specific protection of duplex DNA against restriction and methylation enzymes by pseudocomplementary PNAs

    DEFF Research Database (Denmark)

    Izvolsky, K I; Demidov, V V; Nielsen, P E

    2000-01-01

    I restriction endonuclease and dam methylase. The pcPNA-assisted protection against enzymatic methylation is more efficient when the PNA-binding site embodies the methylase-recognition site rather than overlaps it. We conclude that pcPNAs may provide the robust tools allowing to sequence-specifically manipulate...... DNA duplexes in a virtually sequence-unrestricted manner....

  11. Characterization, expression profiles, intercellular distribution and association analysis of porcine PNAS-4 gene with production traits

    NARCIS (Netherlands)

    Mo, D.L.; Zhu, Z.M.; Pas, te M.F.W.; Li, X.Y.; Yang, S.L.; Wang, H.; Wang, H.L.; Li, K.

    2008-01-01

    Background - In a previous screen to identify differentially expressed genes associated with embryonic development, the porcine PNAS-4 gene had been found. Considering differentially expressed genes in early stages of muscle development are potential candidate genes to improve meat quality and

  12. Characterization, expression profiles, intracellular distribution and association analysis of porcine PNAS-4 gene with production traits

    Directory of Open Access Journals (Sweden)

    Wang Heng

    2008-06-01

    Full Text Available Abstract Background In a previous screen to identify differentially expressed genes associated with embryonic development, the porcine PNAS-4 gene had been found. Considering differentially expressed genes in early stages of muscle development are potential candidate genes to improve meat quality and production efficiency, we determined how porcine PNAS-4 gene regulates meat production. Therefore, this gene has been sequenced, expression analyzed and associated with meat production traits. Results We cloned the full-length cDNA of porcine PNAS-4 gene encoding a protein of 194 amino acids which was expressed in the Golgi complex. This gene was mapped to chromosome 10, q11–16, in a region of conserved synteny with human chromosome 1 where the human homologous gene was localized. Real-time PCR revealed that PNAS-4 mRNA was widely expressed with highest expression levels in skeletal muscle followed by lymph, liver and other tissues, and showed a down-regulated expression pattern during prenatal development while a up-regulated expression pattern after weaning. Association analysis revealed that allele C of SNP A1813C was prevalent in Chinese indigenous breeds whereas A was dominant allele in Landrace and Large White, and the pigs with homozygous CC had a higher fat content than those of the pigs with other genotypes (P Conclusion Porcine PNAS-4 protein tagged with green fluorescent protein accumulated in the Golgi complex, and its mRNA showed a widespread expression across many tissues and organs in pigs. It may be an important factor affecting the meat production efficiency, because its down-regulated expression pattern during early embryogenesis suggests involvement in increase of muscle fiber number. In addition, the SNP A1813C associated with fat traits might be a genetic marker for molecular-assisted selection in animal breeding.

  13. Single-stranded γPNAs for in vivo site-specific genome editing via Watson-Crick recognition.

    Science.gov (United States)

    Bahal, Raman; Quijano, Elias; McNeer, Nicole A; Liu, Yanfeng; Bhunia, Dinesh C; Lopez-Giraldez, Francesco; Fields, Rachel J; Saltzman, William M; Ly, Danith H; Glazer, Peter M

    2014-01-01

    Triplex-forming peptide nucleic acids (PNAs) facilitate gene editing by stimulating recombination of donor DNAs within genomic DNA via site-specific formation of altered helical structures that further stimulate DNA repair. However, PNAs designed for triplex formation are sequence restricted to homopurine sites. Herein we describe a novel strategy where next generation single-stranded gamma PNAsPNAs) containing miniPEG substitutions at the gamma position can target genomic DNA in mouse bone marrow at mixed-sequence sites to induce targeted gene editing. In addition to enhanced binding, γPNAs confer increased solubility and improved formulation into poly(lactic-co-glycolic acid) (PLGA) nanoparticles for efficient intracellular delivery. Single-stranded γPNAs induce targeted gene editing at frequencies of 0.8% in mouse bone marrow cells treated ex vivo and 0.1% in vivo via IV injection, without detectable toxicity. These results suggest that γPNAs may provide a new tool for induced gene editing based on Watson-Crick recognition without sequence restriction.

  14. Document Type Profiles in Nature, Science, and PNAS: Journal and Country Level

    Directory of Open Access Journals (Sweden)

    Jielan Ding

    2016-09-01

    Full Text Available Purpose: In this contribution, we want to detect the document type profiles of the three prestigious journals Nature, Science, and Proceedings of the National Academy of Sciences of the United States (PNAS with regard to two levels: journal and country. Design/methodology/approach: Using relative values based on fractional counting, we investigate the distribution of publications across document types at both the journal and country level, and we use (cosine document type profile similarity values to compare pairs of publication years within countries. Findings: Nature and Science mainly publish Editorial Material, Article, News Item and Letter, whereas the publications of PNAS are heavily concentrated on Article. The shares of Article for Nature and Science are decreasing slightly from 1999 to 2014, while the corresponding shares of Editorial Material are increasing. Most studied countries focus on Article and Letter in Nature, but on Letter in Science and PNAS. The document type profiles of some of the studied countries change to a relatively large extent over publication years. Research limitations: The main limitation of this research concerns the Web of Science classification of publications into document types. Since the analysis of the paper is based on document types of Web of Science, the classification in question is not free from errors, and the accuracy of the analysis might be affected. Practical implications: Results show that Nature and Science are quite diversified with regard to document types. In bibliometric assessments, where publications in Nature and Science play a role, other document types than Article and Review might therefore be taken into account. Originality/value: Results highlight the importance of other document types than Article and Review in Nature and Science. Large differences are also found when comparing the country document type profiles of the three journals with the corresponding profiles in all Web of

  15. Short (

    NARCIS (Netherlands)

    Telleman, Gerdien; den Hartog, Laurens

    2013-01-01

    Aim: This systematic review assessed the implant survival rate of short (<10 mm) dental implants installed in partially edentulous patients. A case report of a short implant in the posterior region have been added. Materials and methods: A search was conducted in the electronic databases of MEDLINE

  16. Exotic woody plant invaders of the Transvaal

    Directory of Open Access Journals (Sweden)

    L. Henderson

    1984-12-01

    Full Text Available The frequency and abundance o ;f exotic, woody plant invaders were recorded in 60% of the quarter degree squares in the study area. Sixty-one invaders were encountered o f which the most important and aggressive were Acacia dealbaia, Populus spp.,  Melia azedarach, Opuntia ficus-indica, Salix babylonica and  Acacia mearnsii. Invasion patterns are discussed and an attempt is made to correlate distribution with environmental factors. Attention is drawn to the areas of greatest invasion and the areas that are liable to show the greatest expansion in the future.

  17. Traits of Heracleum sosnowskyi Plants in Monostand on Invaded Area.

    Directory of Open Access Journals (Sweden)

    Igor V Dalke

    Full Text Available The ability of giant hogweeds to form monodominant communities and even pure monostands in invaded areas has been well documented. Understanding of the mechanisms leading to monostand formation can aid in determining the limitations of existing community ecology models and establishing an effective management plan for invasive species elimination. The aim of this observational study was to investigate traits of Heracleum sosnowskyi plants (demography, canopy structure, morphology and physiology of the plants in a pure stand in an invaded area useful for understanding potential monostand formation mechanisms. All measurements were performed in one typical Heracleum sosnowskyi monostand located in an abandoned agriculture field located in Syktyvkar city suburb (North-east Russia. This monostand consisted of five main plant growth stages: seed, seedling, juvenile, vegetative adult, and generative adult. Plants of all stages began to grow simultaneously shortly after the snowmelt, at the same time as spring ephemeral plant species grew. The density of generative plants did not change during the vegetation period, but the density of the other plant stages rapidly decreased after the formation of a tall (up to 2-2.5 m and dense (Leaf area index up to 6.5 canopy. The canopy captured approximately 97% of the light. H. sosnowskyi showed high (several orders of magnitude higher than average taiga zone grasses photosynthetic water use efficiency (6-7 μM CO2/μM H2O. Formation of H. sosnowskyi monostands occurs primarily in disturbed areas with relatively rich and well-moistened soils. Early commencement of growth, rapid formation of a dense canopy, high efficiency of light and water use during photosynthesis, ability of young plants to survive in low light conditions, rapid recovery of above-ground plant parts after damage, and the high density of the soil seed bank are the most important traits of H. sosnowskyi plants for monostand formation in invaded

  18. Can Daphnia lumholtzi invade European lakes?

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    Meike Wittmann

    2013-03-01

    Full Text Available The cladoceran Daphnia lumholtzi is a subtropical and tropical zooplankter, and an invasive species in North America. Thus far, D. lumholtzi has not been detected in Europe. Here we investigated whether a hypothetical introduction to Europe could result in a successful invasion, either now or in the near future when facilitated by climate change. In laboratory experiments, we tested whether different clones of D. lumholtzi can invade a resident community consisting of native Daphnia from lake Klostersee, Germany, and how invasion success depends on temperature and the presence or absence of planktivorous fish. In some treatments, invasion success was consistently high, and D. lumholtzi reached densities similar to the native competitors by the end of the experiment. The presence of a planktivorous fish reduced the invasion success of D. lumholtzi, and a clone with an inducible defense against fish predation was a more successful invader than a permanently defended clone. Of the three temperatures tested in this study (15, 20, and 24 °C, invasion success was highest at 20 °C. To understand the competitive interaction between native and introduced Daphnia, we fit a Lotka-Volterra-type competition model to the population dynamics. Our experimental and modeling results suggest that D. lumholtzi can invade European lakes and can cause substantial declines in the population size of native Daphnia, with potential consequences for higher trophic levels.

  19. Structural and thermoelectric properties of zintl-phase CaLiPn (Pn=As, Sb, Bi)

    Energy Technology Data Exchange (ETDEWEB)

    Chandran, Anoop K.; Gudelli, Vijay Kumar; Sreeparvathy, P.C.; Kanchana, V., E-mail: kanchana@iith.ac.in

    2016-11-15

    First-principles calculations were carried out to study the structural, mechanical, dynamical and transport properties of zintl phase materials CaLiPn (Pn=As, Sb and Bi). We have used two different approaches to solve the system based on density functional theory. The plane wave pseudopotential approach has been used to study the structural and dynamical properties whereas, full potential linear augment plane wave method is used to examine the electronic structure, mechanical and thermoelectric properties. The calculated ground-state properties agree quite well with experimental values. The computed electronic structure shows the investigated compounds to be direct band gap semiconductors. Further, we have calculated the thermoelectric properties of all the investigated compounds for both the carriers at various temperatures. We found a high thermopower for both the carriers, especially n-type doping to be more favourable, which enabled us to predict that CaLiPn might have promising applications as a good thermoelectric material. Further, the phonon dispersion curves of the investigated compounds showed flat phonon modes and we also find lower optical and acoustic modes to cut each other at the lower frequency range, which further indicate the investigated compounds to possess reasonably low thermal conductivity. We have also analysed the low value of the thermal conductivity through the empirical relations and discussions are presented here. - Highlights: • Electronic band structure and chemical bonding. • Single crystalline elastic constants and poly crystalline elastic moduli. • Thermoelectric properties of zintl phase. • Lattice dynamics and phonon density of states.

  20. Hepatocellular carcinoma directly invading the duodenum

    International Nuclear Information System (INIS)

    Mohamed, Abdelrehman O.; Joshi, Sandhya; Czechowski, Janusz; Branicki, Frank

    2005-01-01

    Recurrent gastrointestinal bleeding from hepatocellular carcinoma (HCC) invading the duodenum is very rare. We present a case of 50-year-old male who was admitted with a history of recurrent upper gastrointestinal tract (UGIT) bleeding, weight loss and anemia. The patient was known to have a chronic hepatitis C. Endoscopic examination showed grade-2 non-bleeding esophageal varices, and a large ulcerated duodenal mass partially obstructing the duodenal bulb outlet and causing recurrent UGIT bleeding. Pathological evaluation of the mass revealed HCC. (author)

  1. Evolution of competitive ability within Lonicera japonica's invaded range

    Science.gov (United States)

    Gregory A. Evans; Francis F. Kilkenny; Laura F. Galloway

    2013-01-01

    Factors influencing invasive taxa may change during the course of an invasion. For example, intraspecific competition is predicted to be more important in areas with older stands of dense monospecific invaders than at the margins of an invaded range. We evaluated evolution in response to predicted changes in competition by comparing the intraspecific competitive...

  2. Isolated Retroperitoneal Hydatid Cyst Invading Splenic Hilum

    Directory of Open Access Journals (Sweden)

    Safak Ozturk

    2014-01-01

    Full Text Available Introduction. Hydatid disease (HD is an infestation that is caused by the larval stage of Echinococcus granulosus. The liver is affected in approximately two-thirds of patients, the lungs in 25%, and other organs in a small proportion. Primary retroperitoneal hydatid cyst is extremely rare. The most common complaint is abdominal pain; however, the clinical features of HD may be generally dependent on the location of the cyst. Case Presentation. A 43-year-old female was admitted with the complaint of abdominal pain. Her physical examination was normal. Computed tomography (CT revealed a 17 × 11 cm cystic lesion, with a thick and smooth wall that is located among the left liver lobe, diaphragm, spleen, tail of the pancreas, and transverse colon and invading the splenic hilum. Total cystectomy and splenectomy were performed. Pathological examination was reported as cyst hydatid. Discussion. Cysts in the peritoneal cavity are mainly the result of the spontaneous or traumatic rupture of concomitant hepatic cysts or surgical inoculation of a hepatic cyst. Serological tests contribute to diagnosis. In symptomatic and large hydatid peritoneal cysts, surgical resection is the only curative treatment. Total cystectomy is the gold standard. Albendazole or praziquantel is indicated for inoperable and disseminated cases. Percutaneous aspiration, injection, and reaspiration (PAIR technique is another nonsurgical option.

  3. Diffuse infiltrating retinoblastoma invading subarachnoid space

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    Kase S

    2011-06-01

    Full Text Available Satoru Kase1, Kazuhiko Yoshida1, Shigenobu Suzuki2, Koh-ichi Ohshima3, Shigeaki Ohno4, Susumu Ishida11Department of Ophthalmology, Hokkaido University Graduate School of Medicine, Sapporo; 2Department of Ophthalmic Oncology, National Cancer Center Hospital, Tokyo; 3Section of Ophthalmology, Okayama Medical Center, Okayama; 4Department of Ocular Inflammation and Immunology, Hokkaido University Graduate School of Medicine, Sapporo, JapanAbstract: We report herein an unusual case of diffuse infiltrating retinoblastoma involving the brain, which caused a patient’s death 27 months after enucleation. An eight-year-old boy complained of blurred vision in his right eye (OD in October 2006. Funduscopic examination showed optic disc swelling, dense whitish vitreous opacity, and an orange-colored subretinal elevated lesion adjacent to the optic disc. Fluorescein angiography revealed hyperfluorescence in the peripapillary region at an early-phase OD. Because the size of the subretinal lesion and vitreous opacity gradually increased, he was referred to us. His visual acuity was 20/1000 OD on June 20, 2007. Slit-lamp biomicroscopy showed a dense anterior vitreous opacity. Ophthalmoscopically, the subretinal orange-colored area spread out until reaching the mid peripheral region. A B-mode sonogram and computed tomography showed a thick homogeneous lesion without calcification. Gadolinium-enhanced magnetic resonance imaging showed a markedly enhanced appearance of the underlying posterior retina. Enucleation of the right eye was performed nine months after the initial presentation. Histopathology demonstrated retinal detachment and a huge choroidal mass invading the optic nerve head. The tumor was consistent with diffuse infiltrating retinoblastoma. The patient died due to brain involvement 27 months after enucleation. Ophthalmologists should be aware that diffuse infiltrating retinoblastoma may show an unfavorable course if its diagnosis is delayed

  4. (α,α-dimethyl)glycyl (dmg) PNAs: achiral PNA analogs that form stronger hybrids with cDNA relative to isosequential RNA.

    Science.gov (United States)

    Gourishankar, Aland; Ganesh, Krishna N

    2012-01-01

    The design and facile synthesis of sterically constrained new analogs of PNA having gem-dimethyl substitutions on glycine (dmg-PNA-T) is presented. The PNA oligomers [aminoethyl dimethylglycyl (aedmg) and aminopropyl dimethylglycyl (apdmg)] synthesized from the monomers 6 and 12) effected remarkable stabilization of homothyminePNA(2):homoadenine DNA/RNA triplexes and mixed base sequence duplexes with target cDNA or RNA. They show a higher binding to DNA relative to that with isosequential RNA. This may be a structural consequence of the sterically rigid gem-dimethyl group, imposing a pre-organized conformation favorable for complex formation with cDNA. The results complement our previous work that had demonstrated that cyclohexanyl-PNAs favor binding with cRNA compared with cDNA and imply that the biophysical and structural properties of PNAs can be directed by introduction of the right rigidity in PNA backbone devoid of chirality. This approach of tweaking selectivity in binding of PNA constructs by installing gem-dimethyl substitution in PNA backbone can be extended to further fine-tuning by similar substitution in the aminoethyl segment as well either individually or in conjunction with present substitution.

  5. Saddam Hussein's Decision to Invade Kuwait - Where Was Plan B

    National Research Council Canada - National Science Library

    Culpepper, Frances R

    1997-01-01

    ... in his decision to invade Kuwait in August 1990 Surveying the damage to the Iraqi economy following the Iran-Iraq war, Saddam knew that insufficient resources would force hum to shelve any domestic program...

  6. Invaders interfere with native parasite-host interactions

    DEFF Research Database (Denmark)

    Thieltges, David W.; Reise, Karsten; Prinz, Katrin

    2009-01-01

    The introduction of species is of increasing concern as invaders often reduce the abundance of native species due to a variety of interactions like habitat engineering, predation and competition. A more subtle and not recognized effect of invaders on their recipient biota is their potential...... interference with native parasite-host interactions. Here, we experimentally demonstrate that two invasive molluscan filter-feeders of European coastal waters interfere with the transmission of free-living infective trematode larval stages and hereby mitigate the parasite burden of native mussels (Mytilus...

  7. Comparison of ground beetle (Coleoptera: Carabidae) assemblages in Rocky Mountain savannas invaded and un-invaded by an exotic forb, spotted knapweed

    Science.gov (United States)

    Allison K. Hansen; Yvette K. Ortega; Diana L. Six

    2009-01-01

    We compared ground beetle (Carabidae) assemblages between spotted knapweed (Centaurea maculosa Lam.) -invaded (invaded) and un-invaded (native) habitats in Rocky Mountain savannas. Carabids play important roles in biotic communities and are known as a good indictor group of environmental change. Carabid species activity-abundance and diversity were estimated, and...

  8. Deja vu? A second mytilid mussel, Semimytilus algosus , invades ...

    African Journals Online (AJOL)

    A second marine mussel is shown to have invaded South Africa's west coast. Molecular techniques, based on intraspecific gene sequence divergences, prove its identity as Semimytilus algosus, a member of the family Mytilidae, native to Chile. The identity of an older introduced population found in Namibia is also ...

  9. Assessment of insect invaders of decaying banana and plantain ...

    African Journals Online (AJOL)

    Insect invaders of decaying banana and plantain pseudo stems in Umuagwo, Ohaji-Egbema, Imo State were investigated in randomly selected crop plots near living homes (<500 m) and far from living homes (.500m). Investigation was done by the use of trapping systems, dissections of cut decaying pseudo stems and ...

  10. Total or partial vertebrectomy for lung cancer invading the spine

    Directory of Open Access Journals (Sweden)

    Soichi Oka

    2016-12-01

    Conclusions: In our experience, Lung cancer surgery combined with vertebrectomy is highly aggressive surgery associated with high morbidity. But, this procedure is a promising treatment option for selected patients, for example N0M0 disease with lung cancer invading the spine.

  11. Prospects for extirpating small populations of the wetland invader ...

    African Journals Online (AJOL)

    The broad-leaved paper bark tree Melaleuca quinquenervia is a major invader in the wetlands of the Florida Everglades, USA. In South Africa, this introduced species is known from eight locality records and is naturalising at two of these sites. The potential for its spread to other wetlands and estuaries is of concern.

  12. Surgical outcomes of hepatocellular carcinoma invading hepatocaval confluence.

    Science.gov (United States)

    Li, Wei; Wu, Hong; Han, Jun

    2016-12-01

    Combined liver and inferior vena cava (IVC) resection followed by IVC and/or hepatic vein reconstruction (HVR) is a curative operation for selected patients with hepatocellular carcinoma (HCC) invading the hepatocaval confluence. The present study aimed to elucidate the prognostic factors for patients with HCC invading the hepatocaval confluence. Forty-two consecutive patients underwent hepatectomy, combined with IVC replacement and/or HVR for HCC between January 2009 and December 2014 were included in this study. The cases were divided into three groups based on the surgical approaches of HVR: group 1 (n=13), tumor invaded the hepatocaval confluence but with one or two hepatic veins intact in the residual liver, thus only the replacement of IVC, not HVR; group 2 (n=23), the hepatic vein of the residual liver was also partially invaded, and the hepatic vein defect was repaired with patches locally; group 3 (n=6), three hepatic veins at the hepatocaval confluence were infiltrated, and the hepatic vein remnant was re-implanted onto the side of the tube graft. The patient characteristics, intra- and postoperative results, and long-term overall survival were compared among the three groups. The survival-related factors were analyzed by univariate and multivariate analysis. The group 1 had higher preoperative alpha-fetoprotein level (PHVR (PHVR (group 1). HVR was one of the unfavorable prognostic factors of overall survival.

  13. Patterns of seed dispersal and establishment of the invader ...

    African Journals Online (AJOL)

    Invasive species in Africa have important impacts on food security and biodiversity conservation. African floodplains in arid areas are critical wildlife habitats in addition to crop production and dry season livestock grazing. The study aimed to understand the patterns of spread of the invader Prosopis juliflora in a typical ...

  14. Habitat heterogeneity influences restoration efficacy: Implications of a habitat-specific management regime for an invaded marsh

    Science.gov (United States)

    Tang, Long; Gao, Yang; Wang, Cheng-Huan; Li, Bo; Chen, Jia-Kuan; Zhao, Bin

    2013-07-01

    Invasive species have to be managed to prevent adverse consequences. Spartina alterniflora has invaded many marshes where salinity and inundation are often key factors affecting vegetation. The former was surface clipped twice and native Phragmites australis was planted in invaded zones to examine the effects of habitat properties on the efficacy of invader control and native restoration. The results showed that two clipping treatments almost eliminated S. alterniflora in the zones with long inundation periods of 80 h/15 d but stimulated compensatory growth of S. alterniflora in the zones with short inundation periods. Transplanted P. australis performed better over time in zones with low salinity (removal of the above-ground parts of S. alterniflora should be used only in the middle tidal zones and that native vegetation should be planted in zones above the mean high water level while the others zones in the saltmarsh should be restored to mud flats. Usually, invasive plants can flourish in highly heterogeneous habitats, which can influence management efficacy by influencing the re-growth of treated invaders and the performance of restored native species. Therefore, habitat-specific management regimes for invasive species can be expected to be more efficient because of their dependence on specific habitats.

  15. Ternary CaCu4P2-type pnictides AAg4Pn2 (A=Sr, Eu; Pn=As, Sb)

    Science.gov (United States)

    Stoyko, Stanislav S.; Khatun, Mansura; Scott Mullen, C.; Mar, Arthur

    2012-08-01

    Four ternary pnictides AAg4Pn2 (A=Sr, Eu; Pn=As, Sb) were prepared by reactions of the elements at 850 °C and their crystal structures were determined from single-crystal X-ray diffraction studies. These silver-containing pnictides AAg4Pn2 adopt the trigonal CaCu4P2-type structure (Pearson symbol hR21, space group R3¯m, Z=3; a=4.5555(6) Å, c=24.041(3) Å for SrAg4As2; a=4.5352(2) Å, c=23.7221(11) Å for EuAg4As2; a=4.7404(4) Å, c=25.029(2) Å for SrAg4Sb2; a=4.7239(3) Å, c=24.689(2) Å for EuAg4Sb2), which can be derived from the trigonal CaAl2Si2-type structure of the isoelectronic zinc-containing pnictides AZn2Pn2 by insertion of additional Ag atoms into trigonal planar sites within [M2Pn2]2- slabs built up of edge-sharing tetrahedra. Band structure calculations on SrAg4As2 and SrAg4Sb2 revealed that these charge-balanced Zintl phases actually exhibit no gap at the Fermi level and are predicted to be semimetals.

  16. Parasites of the raccoon dog – an invading species

    DEFF Research Database (Denmark)

    Al-Sabi, Mohammad Nafi Solaiman; Hammer, A. S.; Chriél, Mariann

    2012-01-01

    Invasive species have a marked negative influence on the biodiversity of ecosystems and may contribute to the transmission of diseases. During the 1920s until 1950s, thousands of Raccoon dogs were deliberately introduces to the eastern European countries from the Far East, in order to enrich...... the wild with this new valuable fur animal. The Raccoon dog is considered the most successful invading mammal in Europe, and in the last 20 years, it has invaded the western part of Denmark, namely Jutland. The Danish ministry of Environment reacted to the new threat by deciding to eradicate this species...... species were isolated from both hosts; however, foxes harboured more helminth species per infected animal (average 3,1 helminth species/fox) than raccoon dogs (average 1,7 helminth species/raccoon dog). Prevalences of nematodes (Uncinaria stenocephala, Toxocara canis and Toxascaris leonine) and cestodes...

  17. Genomic signatures of rapid adaptive evolution in the bluespotted cornetfish, a Mediterranean Lessepsian invader.

    Science.gov (United States)

    Bernardi, Giacomo; Azzurro, Ernesto; Golani, Daniel; Miller, Michael Ryan

    2016-07-01

    Biological invasions are increasingly creating ecological and economical problems both on land and in aquatic environments. For over a century, the Mediterranean Sea has steadily been invaded by Indian Ocean/Red Sea species (called Lessepsian invaders) via the Suez Canal, with a current estimate of ~450 species. The bluespotted cornetfish, Fistularia commersonii, considered a 'Lessepsian sprinter', entered the Mediterranean in 2000 and by 2007 had spread through the entire basin from Israel to Spain. The situation is unique and interesting both because of its unprecedented rapidity and by the fact that it took this species c. 130 years to immigrate into the Mediterranean. Using genome scans, with restriction site-associated DNA (RAD) sequencing, we evaluated neutral and selected genomic regions for Mediterranean vs. Red Sea cornetfish individuals. We found that few fixed neutral changes were detectable among populations. However, almost half of the genes associated with the 47 outlier loci (potentially under selection) were related to disease resistance and osmoregulation. Due to the short time elapsed from the beginning of the invasion to our sampling, we interpret these changes as signatures of rapid adaptation that may be explained by several mechanisms including preadaptation and strong local selection. Such genomic regions are therefore good candidates to further study their role in invasion success. © 2016 John Wiley & Sons Ltd.

  18. Metabolic characterization of invaded cells of the pancreatic cancer cell line, PANC?1

    OpenAIRE

    Fujita, Mayumi; Imadome, Kaori; Imai, Takashi

    2017-01-01

    We previously reported that about 0.4% of cells in the cultured human pancreatic cancer cell line, PANC?1, can invade matrigel during the transwell invasion assay, suggesting that these invaded PANC?1 cells may have specific characteristics to keep their invasive potential. To identify the metabolic characterization specific in the invaded PANC?1 cells, metabolome analysis of the invaded PANC?1 compared with the whole cultured PANC?1 was performed using CE?TOFMS, and concentrations of 110 met...

  19. Area 51: How do Acanthamoeba invade the central nervous system?

    Science.gov (United States)

    Siddiqui, Ruqaiyyah; Emes, Richard; Elsheikha, Hany; Khan, Naveed Ahmed

    2011-05-01

    Acanthamoeba granulomatous encephalitis generally develops as a result of haematogenous spread, but it is unclear how circulating amoebae enter the central nervous system (CNS) and cause inflammation. At present, the mechanisms which Acanthamoeba use to invade this incredibly well-protected area of the CNS and produce infection are not well understood. In this paper, we propose two key virulence factors: mannose-binding protein and extracellular serine proteases as key players in Acanthamoeba traversal of the blood-brain barrier leading to neuronal injury. Both molecules should provide excellent opportunities as potential targets in the rational development of therapeutic interventions against Acanthamoeba encephalitis. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Ternary CaCu4P2-type pnictides AAg4Pn2 (A=Sr, Eu; Pn=As, Sb)

    International Nuclear Information System (INIS)

    Stoyko, Stanislav S.; Khatun, Mansura; Scott Mullen, C.; Mar, Arthur

    2012-01-01

    Four ternary pnictides AAg 4 Pn 2 (A=Sr, Eu; Pn=As, Sb) were prepared by reactions of the elements at 850 °C and their crystal structures were determined from single-crystal X-ray diffraction studies. These silver-containing pnictides AAg 4 Pn 2 adopt the trigonal CaCu 4 P 2 -type structure (Pearson symbol hR21, space group R3-bar m, Z=3; a=4.5555(6) Å, c=24.041(3) Å for SrAg 4 As 2 ; a=4.5352(2) Å, c=23.7221(11) Å for EuAg 4 As 2 ; a=4.7404(4) Å, c=25.029(2) Å for SrAg 4 Sb 2 ; a=4.7239(3) Å, c=24.689(2) Å for EuAg 4 Sb 2 ), which can be derived from the trigonal CaAl 2 Si 2 -type structure of the isoelectronic zinc-containing pnictides AZn 2 Pn 2 by insertion of additional Ag atoms into trigonal planar sites within [M 2 Pn 2 ] 2− slabs built up of edge-sharing tetrahedra. Band structure calculations on SrAg 4 As 2 and SrAg 4 Sb 2 revealed that these charge-balanced Zintl phases actually exhibit no gap at the Fermi level and are predicted to be semimetals. - Graphical abstract: SrAg 4 As 2 and related pnictides adopt a CaCu 4 P 2 -type structure in which additional Ag atoms enter trigonal planar sites within slabs built from edge-sharing tetrahedra. Highlights: ► AAg 4 Pn 2 are the first Ag-containing members of the CaCu 4 P 2 -type structure. ► Ag atoms are stuffed in trigonal planar sites within CaAl 2 Si 2 -type slabs. ► Ag–Ag bonding develops through attractive d 10 –d 10 interactions.

  1. Ternary CaCu{sub 4}P{sub 2}-type pnictides AAg{sub 4}Pn{sub 2} (A=Sr, Eu; Pn=As, Sb)

    Energy Technology Data Exchange (ETDEWEB)

    Stoyko, Stanislav S.; Khatun, Mansura; Scott Mullen, C. [Department of Chemistry, University of Alberta, Edmonton, Alberta, T6G 2G2 (Canada); Mar, Arthur, E-mail: arthur.mar@ualberta.ca [Department of Chemistry, University of Alberta, Edmonton, Alberta, T6G 2G2 (Canada)

    2012-08-15

    Four ternary pnictides AAg{sub 4}Pn{sub 2} (A=Sr, Eu; Pn=As, Sb) were prepared by reactions of the elements at 850 Degree-Sign C and their crystal structures were determined from single-crystal X-ray diffraction studies. These silver-containing pnictides AAg{sub 4}Pn{sub 2} adopt the trigonal CaCu{sub 4}P{sub 2}-type structure (Pearson symbol hR21, space group R3-bar m, Z=3; a=4.5555(6) A, c=24.041(3) A for SrAg{sub 4}As{sub 2}; a=4.5352(2) A, c=23.7221(11) A for EuAg{sub 4}As{sub 2}; a=4.7404(4) A, c=25.029(2) A for SrAg{sub 4}Sb{sub 2}; a=4.7239(3) A, c=24.689(2) A for EuAg{sub 4}Sb{sub 2}), which can be derived from the trigonal CaAl{sub 2}Si{sub 2}-type structure of the isoelectronic zinc-containing pnictides AZn{sub 2}Pn{sub 2} by insertion of additional Ag atoms into trigonal planar sites within [M{sub 2}Pn{sub 2}]{sup 2-} slabs built up of edge-sharing tetrahedra. Band structure calculations on SrAg{sub 4}As{sub 2} and SrAg{sub 4}Sb{sub 2} revealed that these charge-balanced Zintl phases actually exhibit no gap at the Fermi level and are predicted to be semimetals. - Graphical abstract: SrAg{sub 4}As{sub 2} and related pnictides adopt a CaCu{sub 4}P{sub 2}-type structure in which additional Ag atoms enter trigonal planar sites within slabs built from edge-sharing tetrahedra. Highlights: Black-Right-Pointing-Pointer AAg{sub 4}Pn{sub 2} are the first Ag-containing members of the CaCu{sub 4}P{sub 2}-type structure. Black-Right-Pointing-Pointer Ag atoms are stuffed in trigonal planar sites within CaAl{sub 2}Si{sub 2}-type slabs. Black-Right-Pointing-Pointer Ag-Ag bonding develops through attractive d{sup 10}-d{sup 10} interactions.

  2. Effects of a Major Tree Invader on Urban Woodland Arthropods

    Science.gov (United States)

    2015-01-01

    Biological invasions are a major threat to biodiversity; however, the degree of impact can vary depending on the ecosystem and taxa. Here, we test whether a top invader at a global scale, the tree Robinia pseudoacacia (black locust or false acacia), which is known to profoundly change site conditions, significantly affects urban animal diversity. As a first multi-taxon study of this kind, we analyzed the effects of Robinia dominance on 18 arthropod taxa by pairwise comparisons of woodlands in Berlin, Germany, that were dominated by R. pseudoacacia or the native pioneer tree Betula pendula. As a negative effect, abundances of five arthropod taxa decreased (Chilopoda, Formicidae, Diptera, Heteroptera, Hymenoptera); 13 others were not affected. Woodland type affected species composition of carabids and functional groups in spiders, but surprisingly did not decrease alpha and beta diversity of carabid and spider assemblages or the number of endangered species. Tree invasion thus did not induce biotic homogenization at the habitat scale. We detected no positive effects of alien dominance. Our results illustrate that invasions by a major tree invader can induce species turnover in ground-dwelling arthropods, but do not necessarily reduce arthropod species abundances or diversity and might thus contribute to the conservation of epigeal invertebrates in urban settings. Considering the context of invasion impacts thus helps to set priorities in managing biological invasions and can illustrate the potential of novel ecosystems to maintain urban biodiversity. PMID:26359665

  3. Effects of a Major Tree Invader on Urban Woodland Arthropods.

    Directory of Open Access Journals (Sweden)

    Sascha Buchholz

    Full Text Available Biological invasions are a major threat to biodiversity; however, the degree of impact can vary depending on the ecosystem and taxa. Here, we test whether a top invader at a global scale, the tree Robinia pseudoacacia (black locust or false acacia, which is known to profoundly change site conditions, significantly affects urban animal diversity. As a first multi-taxon study of this kind, we analyzed the effects of Robinia dominance on 18 arthropod taxa by pairwise comparisons of woodlands in Berlin, Germany, that were dominated by R. pseudoacacia or the native pioneer tree Betula pendula. As a negative effect, abundances of five arthropod taxa decreased (Chilopoda, Formicidae, Diptera, Heteroptera, Hymenoptera; 13 others were not affected. Woodland type affected species composition of carabids and functional groups in spiders, but surprisingly did not decrease alpha and beta diversity of carabid and spider assemblages or the number of endangered species. Tree invasion thus did not induce biotic homogenization at the habitat scale. We detected no positive effects of alien dominance. Our results illustrate that invasions by a major tree invader can induce species turnover in ground-dwelling arthropods, but do not necessarily reduce arthropod species abundances or diversity and might thus contribute to the conservation of epigeal invertebrates in urban settings. Considering the context of invasion impacts thus helps to set priorities in managing biological invasions and can illustrate the potential of novel ecosystems to maintain urban biodiversity.

  4. Effects of a Major Tree Invader on Urban Woodland Arthropods.

    Science.gov (United States)

    Buchholz, Sascha; Tietze, Hedwig; Kowarik, Ingo; Schirmel, Jens

    2015-01-01

    Biological invasions are a major threat to biodiversity; however, the degree of impact can vary depending on the ecosystem and taxa. Here, we test whether a top invader at a global scale, the tree Robinia pseudoacacia (black locust or false acacia), which is known to profoundly change site conditions, significantly affects urban animal diversity. As a first multi-taxon study of this kind, we analyzed the effects of Robinia dominance on 18 arthropod taxa by pairwise comparisons of woodlands in Berlin, Germany, that were dominated by R. pseudoacacia or the native pioneer tree Betula pendula. As a negative effect, abundances of five arthropod taxa decreased (Chilopoda, Formicidae, Diptera, Heteroptera, Hymenoptera); 13 others were not affected. Woodland type affected species composition of carabids and functional groups in spiders, but surprisingly did not decrease alpha and beta diversity of carabid and spider assemblages or the number of endangered species. Tree invasion thus did not induce biotic homogenization at the habitat scale. We detected no positive effects of alien dominance. Our results illustrate that invasions by a major tree invader can induce species turnover in ground-dwelling arthropods, but do not necessarily reduce arthropod species abundances or diversity and might thus contribute to the conservation of epigeal invertebrates in urban settings. Considering the context of invasion impacts thus helps to set priorities in managing biological invasions and can illustrate the potential of novel ecosystems to maintain urban biodiversity.

  5. Metabolic characterization of invaded cells of the pancreatic cancer cell line, PANC-1.

    Science.gov (United States)

    Fujita, Mayumi; Imadome, Kaori; Imai, Takashi

    2017-05-01

    We previously reported that about 0.4% of cells in the cultured human pancreatic cancer cell line, PANC-1, can invade matrigel during the transwell invasion assay, suggesting that these invaded PANC-1 cells may have specific characteristics to keep their invasive potential. To identify the metabolic characterization specific in the invaded PANC-1 cells, metabolome analysis of the invaded PANC-1 compared with the whole cultured PANC-1 was performed using CE-TOFMS, and concentrations of 110 metabolites were measured. In contrast to the whole cultured cells, the invaded PANC-1 was characterized as a population with reduced levels of amino acids and TCA cycle intermediates, and decreased and increased intermediates in glycolysis and nucleic acid metabolism. In particular, the ratio of both adenosine and guanosine energy charge was reduced in the invaded cells, revealing that the consumption of ATP and GTP was high in the invaded cells, and thus suggesting that ATP- or GTP-generating pathways are stimulated. In addition, the GSH/GSSG ratio was low in the invaded cells, but these cells had a higher surviving fraction after exposure to hydrogen peroxide. Thus, the invaded cells were the population resistant to oxidative stress. Furthermore, reduction in intracellular GSH content inhibited PANC-1 invasiveness, indicated that GSH has an important role in PANC-1 invasiveness. Overall, we propose the invaded cells have several unique metabolic profiles. © 2017 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

  6. Efficacy of prophylactic splenectomy for proximal advanced gastric cancer invading greater curvature.

    Science.gov (United States)

    Ohkura, Yu; Haruta, Shusuke; Shindoh, Junichi; Tanaka, Tsuyoshi; Ueno, Masaki; Udagawa, Harushi

    2017-05-25

    For proximal gastric cancer invading the greater curvature, concomitant splenectomy is frequently performed to secure the clearance of lymph node metastases. However, prognostic impact of prophylactic splenectomy remains unclear. The aim of this study was to clarify the oncological significance of prophylactic splenectomy for advanced proximal gastric cancer invading the greater curvature. Retrospective review of 108 patients who underwent total or subtotal gastrectomy for advanced proximal gastric cancer involving the greater curvature was performed. Short-term and long-term outcomes were compared between the patients who underwent splenectomy (n = 63) and those who did not (n = 45). Patients who underwent splenectomy showed higher amount of blood loss (538 vs. 450 mL, p = 0.016) and morbidity rate (30.2 vs. 13.3, p = 0.041) compared with those who did not undergo splenectomy. In particular, pancreas-related complications were frequently observed among patients who received splenectomy (17.4 vs. 0%, p = 0.003). However, no significant improvement of long-term outcomes were confirmed in the cases with splenectomy (5-year recurrence-free rate, 60.2 vs. 67.3%; p = 0.609 and 5-year overall survival rates, 63.7 vs. 73.6%; p = 0.769). On the other hand, splenectomy was correlated with marginally better survival in patients with Borrmann type 1 or 2 gastric cancer (p = 0.072). For advanced proximal gastric cancer involving the greater curvature, prophylactic splenectomy may have no significant prognostic impact despite the increased morbidity rate after surgery. Such surgical procedure should be avoided as long as lymph node involvement is not evident.

  7. Preoperative radiation therapy for muscle-invading bladder carcinoma

    International Nuclear Information System (INIS)

    Cox, J.A.; Greven, K.M.; Anscher, M.S.; Morgan, T.M.; Scott, J.

    1991-01-01

    This paper reports on low-dose and high-dose radiation therapy (RT) followed by cystectomy for bladder carcinoma that was evaluated for survival, failure patterns, and complications as these outcomes have been incompletely documented in the past. One hundred five patients with clinical stages T2-T4 (muscle-invading) transitional cell carcinoma of the bladder who completed preoperative RT followed by total cystectomy were evaluated. Eighty-five patients received 20-27 Gy in 4-7 fractions (group A). Twenty patients received 40-50 Gy in 20-28 fractions (group B). Actuarial 5-year survival was 45% and 29% (P = .06) for groups A and B, respectively; 6% of group A was stage T4 compared with 30% of group B. Five-year actuarial survival for patients with stages T2-T3 in groups A and B was 46% and 42%, respectively, while that for T4 was 33% and 0% in groups A and B, respectively. Multivariate analysis revealed that stage, grade, and presence of hydronephrosis independently affected survival. Five-year actuarial local control rates for T2, T3, and T4 were 93%, 93%, and 22%, respectively, with no significant difference between RT groups. Rates of distant metastasis and complications versus preoperative regime and stage were similar

  8. Vegetative Regeneration Capacities of Five Ornamental Plant Invaders After Shredding

    Science.gov (United States)

    Monty, Arnaud; Eugène, Marie; Mahy, Grégory

    2015-02-01

    Vegetation management often involves shredding to dispose of cut plant material or to destroy the vegetation itself. In the case of invasive plants, this can represent an environmental risk if the shredded material exhibits vegetative regeneration capacities. We tested the effect of shredding on aboveground and below-ground vegetative material of five ornamental widespread invaders in Western Europe that are likely to be managed by cutting and shredding techniques: Buddleja davidii (butterfly bush, Scrophulariaceae), Fallopia japonica (Japanese knotweed, Polygonaceae), Spiraea × billardii Hérincq (Billard's bridewort, Rosaceae), Solidago gigantea (giant goldenrod, Asteraceae), and Rhus typhina L. (staghorn sumac, Anacardiaceae). We looked at signs of vegetative regeneration and biomass production, and analyzed the data with respect to the season of plant cutting (spring vs summer), the type of plant material (aboveground vs below-ground), and the shredding treatment (shredded vs control). All species were capable of vegetative regeneration, especially the below-ground material. We found differences among species, but the regeneration potential was generally still present after shredding despite a reduction of growth rates. Although it should not be excluded in all cases (e.g., destruction of giant goldenrod and staghorn sumac aboveground material), the use of a shredder to destroy woody alien plant material cannot be considered as a general management option without significant environmental risk.

  9. Experimental control of Spanish broom (Spartium junceum invading natural grasslands

    Directory of Open Access Journals (Sweden)

    Cristina Sanhueza

    2012-12-01

    Full Text Available A group of legumes generically known as brooms are among the most successful shrubs invading grasslands in South America and otherregions. These species share a set of biological features that enhance their invasiveness, such as abundant and long-lasting seed banks,aggressive root systems and rapid growth, combined with their ability for re-sprouting after cutting or burning and for avoiding herbivores.They grow in dense stands that exclude native vegetation and are able to change ecological processes, increasing fire frequency and intensity,and fixing atmospheric nitrogen. The Spanish broom (Spartium junceum is a shrub native form the Mediterranean that was introduced intothe Argentine Pampas grasslands where it spreads over remnants of pristine ecosystems, threatening their biodiversity. This paper reports theresults obtained after an adaptive management strategy aimed at controlling this species in a nature reserve, and compares the efficiency ofdifferent mechanical and chemical control techniques in terms of the number of plants killed and the effects on surrounding vegetation andon the recruitment of broom seedlings. Control was implemented in two phases, the first included three treatments: i cut at the base of theplant, ii cut followed by the immediate application of Togar (Picloram 3% + Triclopyr 6%, at a 5% dilution in diesel oil on top of the cut stump, and iii foliar spraying with Togar. The follow-up treatments, implemented one year later, consisted of spraying the re-sprouts with Togar (5% in diesel oil or Glyphosate 36% (2% in water. The best option in terms of controlling Spanish broom was spraying the resprouts with Togar which gave 100% mortality of the treated plants, compared with values of 40% - 100% re-sprouting for the other optionstested. None of the methods was associated with an increase in seedling recruitment, nor with significant changes in the vegetation in the immediate vicinity of the controlled brooms.

  10. Ecosystem impacts of exotic annual invaders in the Genus Bromus

    Science.gov (United States)

    Germino, Matthew J.; Belnap, Jayne; Stark, John M.; Allen, Edith B.; Rau, Benjamin M.

    2016-01-01

    An understanding of the impacts of exotic plant species on ecosystems is necessary to justify and guide efforts to limit their spread, restore natives, and plan for conservation. Invasive annual grasses such as Bromus tectorum, B. rubens, B. hordeaceus, and B. diandrus (hereafter collectively referred to as Bromus) transform the structure and function of ecosystems they dominate. Experiments that prove cause-and-effect impacts of Bromus are rare, yet inferences can be gleaned from the combination of Bromus-ecosystem associations, ecosystem condition before/after invasion, and an understanding of underlying mechanisms. Bromus typically establishes in bare soil patches and can eventually replace perennials such as woody species or bunchgrasses, creating a homogeneous annual cover. Plant productivity and cover are less stable across seasons and years when Bromus dominates, due to a greater response to annual climate variability. Bromus’ “flash” of growth followed by senescence early in the growing season, combined with shallow rooting and annual habit, may lead to incomplete use of deep soil water, reduced C sequestration, and accelerated nutrient cycling. Litter produced by Bromus alters nearly all aspects of ecosystems and notably increases wildfire occurrence. Where Bromus has become dominant, it can decrease soil stability by rendering soils bare for months following fire or episodic, pathogen-induced stand failure. Bromus-invaded communities have lower species diversity, and associated species tend to be generalists adapted to unstable and variable habitats. Changes in litter, fire, and soil properties appear to feedback to reinforce Bromus’ dominance in a pattern that portends desertification.

  11. Grassland invader responses to realistic changes in native species richness.

    Science.gov (United States)

    Rinella, Matthew J; Pokorny, Monica L; Rekaya, Romdhane

    2007-09-01

    The importance of species richness for repelling exotic plant invasions varies from ecosystem to ecosystem. Thus, in order to prioritize conservation objectives, it is critical to identify those ecosystems where decreasing richness will most greatly magnify invasion risks. Our goal was to determine if invasion risks greatly increase in response to common reductions in grassland species richness. We imposed treatments that mimic management-induced reductions in grassland species richness (i.e., removal of shallow- and/or deep-rooted forbs and/or grasses and/or cryptogam layers). Then we introduced and monitored the performance of a notorious invasive species (i.e., Centaurea maculosa). We found that, on a per-gram-of-biomass basis, each resident plant group similarly suppressed invader growth. Hence, with respect to preventing C. maculosa invasions, maintaining overall productivity is probably more important than maintaining the productivity of particular plant groups or species. But at the sites we studied, all plant groups may be needed to maintain overall productivity because removing forbs decreased overall productivity in two of three years. Alternatively, removing forbs increased productivity in another year, and this led us to posit that removing forbs may inflate the temporal productivity variance as opposed to greatly affecting time-averaged productivity. In either case, overall productivity responses to single plant group removals were inconsistent and fairly modest, and only when all plant groups were removed did C. maculosa growth increase substantially over a no-removal treatment. As such, it seems that intense disturbances (e.g., prolonged drought, overgrazing) that deplete multiple plant groups may often be a prerequisite for C. maculosa invasion.

  12. Competitive interactions between co-occurring invaders: identifying asymmetries between two invasive crayfish species

    NARCIS (Netherlands)

    Hudina, S.; Galic, N.G.; Roessink, I.; Hock, K.

    2011-01-01

    Ecosystems today increasingly suffer invasions by multiple invasive species. Complex interactions between invasive species can have different fitness implications for each invader, which can in turn determine the future progression of their invasions and result in differential impacts on native

  13. Investigation of Darwin’s naturalization hypothesis in invaded macrophyte communities

    Science.gov (United States)

    Although native macrophytes are beneficial in aquatic ecosystems, invasive macrophytes can cause significant ecological and economic harm. Numerous studies have attributed invasiveness to species’ characteristics, whereas others attribute invasion to biotic and abiotic characteristics of the invaded...

  14. Success of seeding native compared with introduced perennial vegetation for revegetating medusahead-invaded sagebrush rangeland

    Science.gov (United States)

    Millions of hectares of Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis Beetle &Young) rangeland have been invaded by medusahead (Taeniatherum caput-medusae [L.] Nevski), an exotic annual grass that degrades wildlife habitat, reduces forage production, and decreases biodiversity....

  15. Predicting the spread of aquatic invaders: insight from 200 years of invasion by zebra mussels.

    Science.gov (United States)

    Karatayev, Alexander Y; Burlakova, Lyubov E; Mastitsky, Sergey E; Padilla, Dianna K

    2015-03-01

    Understanding factors controlling the introduction and spread of species is crucial to improving the management of both natural populations and introduced species. The zebra mussel, Dreissena polymorpha, is considered the most aggressive freshwater invader in the Northern Hemisphere, and is a convenient model system for invasion biology, offering one of the best aquatic examples for examining the invasion process. We used data on 553 of the 1040 glacial lakes in the Republic of Belarus that were examined for the presence of zebra mussels. We used these data to build, test, and construct modified models to predict the spread of this invader, including selection of important parameters that could limit the spread of this invader. In spite of 200 years of continuous invasion, by 1996, zebra mussels were found in only 16.8% of all lakes studied. Of those lakes without zebra mussels in 1996, 66% were predicted to be susceptible to invasion by zebra mussels in the future, and 33% were predicted to be immune to successful invasion due to their water chemistry. Eighty lakes free of zebra mussels in 1996 were reexamined from 1997 to 2008. Of these, zebra mussels successfully invaded an additional 31 lakes, all of which were classified initially as suitable for zebra mussels; none of the lakes previously classified as unsuitable were invaded. We used the Random Forests classification algorithm with 16 environmental variables to determine the most important factors that differed between invaded lakes and those lakes suitable for invasion that have not yet been invaded. Distance to the nearest infested lakes was found to be the most important variable, followed by the lake area, color, average depth, and concentration of chloride, magnesium, and bicarbonate. This study provides a useful approach for predicting the spread of an invader across a landscape with variable habitat suitability that can be applied to a variety of species and systems.

  16. Alien plant invasions--incorporating emerging invaders in regional prioritization: a pragmatic approach for Southern Africa.

    Science.gov (United States)

    Mgidi, Theresa N; Le Maitre, David C; Schonegevel, Lucille; Nel, Jeanne L; Rouget, Mathieu; Richardson, David M

    2007-07-01

    Plant invasions are a serious threat to natural and semi-natural ecosystems worldwide. Most management-orientated research on invasions focuses on invaders that are already widespread and often have major impacts. This paper deals with "emerging" invaders-those alien species with the potential to become important problems without timely intervention. A climate matching procedure was developed to define areas of South Africa, Lesotho and Swaziland that could be invaded by 28 plant species that had previously been classified as emerging invaders. Information on the location of populations of these species in the study area was combined with information on their distributions (as native or alien) in parts of Australia and the United States of America. These two countries had the best available distribution data for this study. They also share many invasive alien plant species with South Africa. Climatic data obtained for weather stations near points of known occurrence in these countries were used to define the climatically suitable areas for each species in the study area. Almost 80% of the remaining natural environment in southern Africa was found to be vulnerable to invasion by at least one of these species, 50% by six or more and 24% by 16 or more species. The most vulnerable areas are the highveld grasslands and the eastern escarpment. The emerging invaders with the greatest potential range included Acacia podalyriifolia and Cortaderia selloana. The globally important invaders Ulex europaeus and Lythrum salicaria had a more limited invasion potential but could still become major invaders. There was no relationship between the extent of the climatically suitable areas for the different species and an expert ranking of their invasion potential, emphasising the uncertainties inherent in making expert assessments based on very little information. The methods used in this analysis establish a protocol for future modelling exercises to assess the invasion potential of

  17. Native birds and alien insects: spatial density dependence in songbird predation of invading oak gallwasps.

    Directory of Open Access Journals (Sweden)

    Karsten Schönrogge

    Full Text Available Revealing the interactions between alien species and native communities is central to understanding the ecological consequences of range expansion. Much has been learned through study of the communities developing around invading herbivorous insects. Much less, however, is known about the significance of such aliens for native vertebrate predators for which invaders may represent a novel food source. We quantified spatial patterns in native bird predation of invading gall-inducing Andricus wasps associated with introduced Turkey oak (Quercus cerris at eight sites across the UK. These gallwasps are available at high density before the emergence of caterpillars that are the principle spring food of native insectivorous birds. Native birds showed positive spatial density dependence in gall attack rates at two sites in southern England, foraging most extensively on trees with highest gall densities. In a subsequent study at one of these sites, positive spatial density dependence persisted through four of five sequential week-long periods of data collection. Both patterns imply that invading galls are a significant resource for at least some native bird populations. Density dependence was strongest in southern UK bird populations that have had longest exposure to the invading gallwasps. We hypothesise that this pattern results from the time taken for native bird populations to learn how to exploit this novel resource.

  18. Spreaders, igniters, and burning shrubs: plant flammability explains novel fire dynamics in grass-invaded deserts.

    Science.gov (United States)

    Fuentes-Ramirez, Andres; Veldman, Joseph W; Holzapfel, Claus; Moloney, Kirk A

    2016-10-01

    Novel fire regimes are an important cause and consequence of global environmental change that involve interactions among biotic, climatic, and human components of ecosystems. Plant flammability is key to these interactions, yet few studies directly measure flammability or consider how multiple species with different flammabilities interact to produce novel fire regimes. Deserts of the southwestern United States are an ideal system for exploring how novel fire regimes can emerge when fire-promoting species invade ecosystems comprised of species that did not evolve with fire. In these deserts, exotic annual grasses provide fuel continuity across landscapes that did not historically burn. These fires often ignite a keystone desert shrub, the fire-intolerant creosote bush, Larrea tridentata (DC.) Coville. Ignition of Larrea is likely catalyzed by fuels produced by native plants that grow beneath the shrubs. We hypothesize that invasive and native species exhibit distinct flammability characteristics that in combination determine spatial patterns of fire spread and intensity. We measured flammability metrics of Larrea, two invasive grasses, Schismus arabicus and Bromus madritensis, and two native plants, the sub-shrub Ambrosia dumosa and the annual herb Amsinckia menziesii. Results of laboratory experiments show that the grasses carry fire quickly (1.32 cm/s), but burn for short duration (0.5 min) at low temperatures. In contrast, native plants spread fire slowly (0.12 cm/s), but burn up to eight times longer (4 min) and produced hotter fires. Additional experiments on the ignition requirements of Larrea suggest that native plants burn with sufficient temperature and duration to ignite dead Larrea branches (time to ignition, 2 min; temperature at ignition 692°C). Once burning, these dead branches ignite living branches in the upper portions of the shrub. Our study provides support for a conceptual model in which exotic grasses are "spreaders" of fire and native

  19. Impact of invading alien plants on surface water resources in South Africa: a preliminary assessment

    CSIR Research Space (South Africa)

    Le Maitre, David C

    2000-07-01

    Full Text Available areas (the equivalent area with a canopy cover of 100%). Each of the invading species was classified as a tall shrub, medium tree or tall tree - based on growth form and likely water use - and its biomass was estimated from a function based on vegetation...

  20. Prescribed fire opportunities in grasslands invaded by Douglas-fir: state-of-the-art guidelines

    Science.gov (United States)

    George E. Gruell; James K. Brown; Charles L. Bushey

    1986-01-01

    Provides information on use of prescribed fire to enhance productivity of bunchgrass ranges that have been invaded by Douglas-fir. Six vegetative "situations" representative of treatment opportunities most commonly encountered in Montana are discussed. Included are fire prescription considerations and identification of the resource objective, fire objective,...

  1. Comparing methods for measuring the rate of spread of invading populations

    Science.gov (United States)

    Marius Gilbert; Andrew. Liebhold

    2010-01-01

    Measuring rates of spread during biological invasions is important for predicting where and when invading organisms will spread in the future as well as for quantifying the influence of environmental conditions on invasion speed. While several methods have been proposed in the literature to measure spread rates, a comprehensive comparison of their accuracy when applied...

  2. Strategic management of five deciduous forest invaders using Microstegium vimineum as a model species

    Science.gov (United States)

    Cynthia D. Huebner

    2007-01-01

    This paper links key plant invasive traits with key landscape traits to define strategic management for five common forest invaders, using empirical data of Microstegium vimineum dispersal into forests as a preliminary model. Microstegium vimineum exhibits an Allee effect that may allow management to focus on treating its source...

  3. Habitat shift in invading species: Zebra and quagga mussel population characteristics on shallow soft substrates

    Science.gov (United States)

    Berkman, P.A.; Garton, D.W.; Haltuch, M.A.; Kennedy, G.W.; Febo, L.R.

    2000-01-01

    Unexpected habitat innovations among invading species are illustrated by the expansion of dreissenid mussels across sedimentary environments in shallow water unlike the hard substrates where they are conventionally known. In this note, records of population characteristics of invading zebra (Dreissena polymorpha) and quagga (Dreissena bugensis) mussels from 1994 through 1998 are reported from shallow (less than 20 m) sedimentary habitats in western Lake Erie. Haphazard SCUBA collections of these invading species indicated that combined densities of zebra and quagga mussels ranged from 0 to 32,500 individuals per square meter between 1994 and 1998, with D. polymorpha comprising 75-100% of the assemblages. These mixed mussel populations, which were attached by byssal threads to each other and underlying sand-grain sediments, had size-frequency distributions that were typical of colonizing populations on hard substrates. Moreover, the presence of two mussel cohorts within the 1994 samples indicated that these species began expanding onto soft substrates not later than 1992, within 4 years of their initial invasion in western Lake Erie. Such historical data provide baselines for interpreting adaptive innovations, ecological interactions and habitat shifts among the two invading dreissenid mussel species in North America.

  4. Management process invaded Ames as the Center shifted from NACA to NASA oversight. Ames constructed

    Science.gov (United States)

    1968-01-01

    Management process invaded Ames as the Center shifted from NACA to NASA oversight. Ames constructed a review room in its headquarters building where, in the graphical style that prevailed in the 1960's, Ames leadership could review progress against schedule, budget and performance measures. Shown, in October 1965 is Merrill Mead chief of Ames' program and resources office. (for H Julian Allen Retirement album)

  5. Plant invasions in the Czech Republic: current state, introduction dynamics, invasive species and invaded habitats

    Czech Academy of Sciences Publication Activity Database

    Pyšek, Petr; Chytrý, M.; Pergl, Jan; Sádlo, Jiří; Wild, Jan

    2012-01-01

    Roč. 84, č. 3 (2012), s. 575-629 ISSN 0032-7786 R&D Projects: GA ČR(CZ) GAP504/11/1028 Institutional research plan: CEZ:AV0Z60050516 Institutional support: RVO:67985939 Keywords : invasive species * invaded habitats * Czech Republic Subject RIV: EF - Botanics Impact factor: 2.833, year: 2012

  6. Global Invader Impact Network (GIIN): toward standardized evaluation of the ecological impacts of invasive plants.

    Science.gov (United States)

    Barney, Jacob N; Tekiela, Daniel R; Barrios-Garcia, Maria Noelia; Dimarco, Romina D; Hufbauer, Ruth A; Leipzig-Scott, Peter; Nuñez, Martin A; Pauchard, Aníbal; Pyšek, Petr; Vítková, Michaela; Maxwell, Bruce D

    2015-07-01

    Terrestrial invasive plants are a global problem and are becoming ubiquitous components of most ecosystems. They are implicated in altering disturbance regimes, reducing biodiversity, and changing ecosystem function, sometimes in profound and irreversible ways. However, the ecological impacts of most invasive plants have not been studied experimentally, and most research to date focuses on few types of impacts, which can vary greatly among studies. Thus, our knowledge of existing ecological impacts ascribed to invasive plants is surprisingly limited in both breadth and depth. Our aim was to propose a standard methodology for quantifying baseline ecological impact that, in theory, is scalable to any terrestrial plant invader (e.g., annual grasses to trees) and any invaded system (e.g., grassland to forest). The Global Invader Impact Network (GIIN) is a coordinated distributed experiment composed of an observational and manipulative methodology. The protocol consists of a series of plots located in (1) an invaded area; (2) an adjacent removal treatment within the invaded area; and (3) a spatially separate uninvaded area thought to be similar to pre-invasion conditions of the invaded area. A standardized and inexpensive suite of community, soil, and ecosystem metrics are collected allowing broad comparisons among measurements, populations, and species. The method allows for one-time comparisons and for long-term monitoring enabling one to derive information about change due to invasion over time. Invader removal plots will also allow for quantification of legacy effects and their return rates, which will be monitored for several years. GIIN uses a nested hierarchical scale approach encompassing multiple sites, regions, and continents. Currently, GIIN has network members in six countries, with new members encouraged. To date, study species include representatives of annual and perennial grasses; annual and perennial forbs; shrubs; and trees. The goal of the GIIN

  7. Impacts of invading alien plant species on water flows at stand and catchment scales

    Science.gov (United States)

    Le Maitre, D. C.; Gush, M. B.; Dzikiti, S.

    2015-01-01

    There have been many studies of the diverse impacts of invasions by alien plants but few have assessed impacts on water resources. We reviewed the information on the impacts of invasions on surface runoff and groundwater resources at stand to catchment scales and covering a full annual cycle. Most of the research is South African so the emphasis is on South Africa's major invaders with data from commercial forest plantations where relevant. Catchment studies worldwide have shown that changes in vegetation structure and the physiology of the dominant plant species result in changes in surface runoff and groundwater discharge, whether they involve native or alien plant species. Where there is little change in vegetation structure [e.g. leaf area (index), height, rooting depth and seasonality] the effects of invasions generally are small or undetectable. In South Africa, the most important woody invaders typically are taller and deeper rooted than the native species. The impacts of changes in evaporation (and thus runoff) in dryland settings are constrained by water availability to the plants and, thus, by rainfall. Where the dryland invaders are evergreen and the native vegetation (grass) is seasonal, the increases can reach 300–400 mm/year. Where the native vegetation is evergreen (shrublands) the increases are ∼200–300 mm/year. Where water availability is greater (riparian settings or shallow water tables), invading tree water-use can reach 1.5–2.0 times that of the same species in a dryland setting. So, riparian invasions have a much greater impact per unit area invaded than dryland invasions. The available data are scattered and incomplete, and there are many gaps and issues that must be addressed before a thorough understanding of the impacts at the site scale can be gained and used in extrapolating to watershed scales, and in converting changes in flows to water supply system yields. PMID:25935861

  8. Scaling the consequences of interactions between invaders from the individual to the population level.

    Science.gov (United States)

    Griffen, Blaine D

    2016-03-01

    The impact of human-induced stressors, such as invasive species, is often measured at the organismal level, but is much less commonly scaled up to the population level. Interactions with invasive species represent an increasingly common source of stressor in many habitats. However, due to the increasing abundance of invasive species around the globe, invasive species now commonly cause stresses not only for native species in invaded areas, but also for other invasive species. I examine the European green crab Carcinus maenas, an invasive species along the northeast coast of North America, which is known to be negatively impacted in this invaded region by interactions with the invasive Asian shore crab Hemigrapsus sanguineus. Asian shore crabs are known to negatively impact green crabs via two mechanisms: by directly preying on green crab juveniles and by indirectly reducing green crab fecundity via interference (and potentially exploitative) competition that alters green crab diets. I used life-table analyses to scale these two mechanistic stressors up to the population level in order to examine their relative impacts on green crab populations. I demonstrate that lost fecundity has larger impacts on per capita population growth rates, but that both predation and lost fecundity are capable of reducing population growth sufficiently to produce the declines in green crab populations that have been observed in areas where these two species overlap. By scaling up the impacts of one invader on a second invader, I have demonstrated that multiple documented interactions between these species are capable of having population-level impacts and that both may be contributing to the decline of European green crabs in their invaded range on the east coast of North America.

  9. Impacts of invading alien plant species on water flows at stand and catchment scales.

    Science.gov (United States)

    Le Maitre, D C; Gush, M B; Dzikiti, S

    2015-05-01

    There have been many studies of the diverse impacts of invasions by alien plants but few have assessed impacts on water resources. We reviewed the information on the impacts of invasions on surface runoff and groundwater resources at stand to catchment scales and covering a full annual cycle. Most of the research is South African so the emphasis is on South Africa's major invaders with data from commercial forest plantations where relevant. Catchment studies worldwide have shown that changes in vegetation structure and the physiology of the dominant plant species result in changes in surface runoff and groundwater discharge, whether they involve native or alien plant species. Where there is little change in vegetation structure [e.g. leaf area (index), height, rooting depth and seasonality] the effects of invasions generally are small or undetectable. In South Africa, the most important woody invaders typically are taller and deeper rooted than the native species. The impacts of changes in evaporation (and thus runoff) in dryland settings are constrained by water availability to the plants and, thus, by rainfall. Where the dryland invaders are evergreen and the native vegetation (grass) is seasonal, the increases can reach 300-400 mm/year. Where the native vegetation is evergreen (shrublands) the increases are ∼200-300 mm/year. Where water availability is greater (riparian settings or shallow water tables), invading tree water-use can reach 1.5-2.0 times that of the same species in a dryland setting. So, riparian invasions have a much greater impact per unit area invaded than dryland invasions. The available data are scattered and incomplete, and there are many gaps and issues that must be addressed before a thorough understanding of the impacts at the site scale can be gained and used in extrapolating to watershed scales, and in converting changes in flows to water supply system yields. Published by Oxford University Press on behalf of the Annals of Botany

  10. Invading Bologna

    DEFF Research Database (Denmark)

    Schaub Jr, Gary John; Breitenbauch, Henrik Ø.; Pradhan-Blach, Flemming

    European NATO nations need better staff officers. Operation Unified Protector exposed a widespread deficiency in the professional knowledge of field-grade European officers. Professional military education (PME) is where corrective Alliance action must focus. The Nordic countries—Norway, Denmark...

  11. Contribution to the alien flora of Montenegro and Supplementum to the Preliminary list of plant invaders

    Directory of Open Access Journals (Sweden)

    Stešević, D.

    2013-12-01

    Full Text Available This contribution is based on the field observations from 2011 to 2013. Besides new data about distribution of some known plant invaders, one new alien species for the flora of Montenegro is reported- Solidago gigantea. This plant was recorded in 2011, on two distinct localities near the road side in peri-urban area of Nikšić and Mojkovac, in the vicinity of gardens, were it has been grown as ornamental. In 2012 survey, species was again reported for Mojkovac, but it disappeared from Nikšić, due to environmental changes caused by road construction. Remaining locality is placed near the Tara river bank, so considering ecological preferences (roadsides, disturbed river banks and moist soils, this species might become more frequent in the area. It is included into the EPPO list of invasive alien plants. In addition, alien plant Tagetes minuta is added to the preliminary list of plant invaders in Montenegro.

  12. A taste for novelty in invading house sparrows, Passer domesticus

    OpenAIRE

    Lynn B. Martin; Lisa Fitzgerald

    2005-01-01

    One of the central questions in invasion biology involves why some introductions succeed and others fail. Although several correlates of invasion success have been identified, patterns alone cannot identify the mechanisms underlying the invasion process. Here, we test the hypothesis that one predictor of invasion success, behavioral flexibility, is different between invading and established populations of the same species of bird. We predicted that neophobia (fear of novelty), a surrogate of ...

  13. Magnetic Resonance Imaging of a Liver Hydatid Cyst Invading the Portal Vein and Causing Portal Cavernomatosis.

    Science.gov (United States)

    Herek, Duygu; Sungurtekin, Ugur

    2015-01-01

    Hepatic hydatid cysts rarely invade portal veins causing portal cavernomatosis as a secondary complication. We report the case of a patient with direct invasion of the right portal vein by hydatid cysts causing portal cavernomatosis diagnosed via magnetic resonance imaging (MRI). The presented case highlights the useful application of MRI with T2-weighted images and gadolinium-enhanced T1-weighted images in the diagnosis of hepatic hydatid lesions presenting with a rare complication of portal cavernomatosis.

  14. Stoichiometric Constraints Do Not Limit Successful Invaders: Zebra Mussels in Swedish Lakes

    OpenAIRE

    Naddafi, Rahmat; Ekl?v, Peter; Pettersson, Kurt

    2009-01-01

    Background Elemental imbalances of carbon (C): nitrogen (N): phosphorus (P) ratios in food resources can constrain the growth of grazers owning to tight coupling between growth rate, RNA allocation and biomass P content in animals. Testing for stoichiometric constraints among invasive species is a novel challenge in invasion ecology to unravel how a successful invader tackles ecological barriers in novel ecosystems. Methodology/Principal Findings We examined the C?P and N?P ratios and the con...

  15. Mapping cryptic invaders and invisability of tropical forest ecosystems: Chromolaena odorata in Nepal

    OpenAIRE

    Joshi, C.

    2006-01-01

    For centuries, people continuously increased the rate of biological invasions and there is no sign of slowing down. From the depth of the Ocean to the crest of Himalayas, they are occupying pristine and semi-natural ecosystems at an alarming rate, threatening human, animal, plant as well as ecosystem health. Efforts to avoid or eradicate them are not achievable except for very few cases. Currently, therefore, their management aims at controlling invaders and mitigating their impact rather tha...

  16. Distinguishing neuroblastoma invading the kidney from nephroblastoma: evaluation in computed tomography

    International Nuclear Information System (INIS)

    Qiao Zhongwei; Li Guoping; Mamier; Wang Kang'an; Lv Zhibao; Miao Fei

    2005-01-01

    Objective: To evaluate the CT findings in the differential diagnosis between neuroblastoma invading the kidney and nephroblastoma. Methods: CT morphologic details in 13 patients with neuroblastoma invading the kidney confirmed by surgical operation and pathology were studied, and CT findings in 15 patients with nephroblastoma confirmed by surgery and pathology were compared. Results: In 13 cases of neuroblastoma, CT showed irregular mass in 12 cases, tumor with poorly defined margins in 11 cases, tumorous calcifications in 10 cases, invasion of retroperitoneal vessels in 9 cases, and retroperitoneal and retrocrural lymph nodes invasion in 12 cases. In 15 cases of nephroblastoma, round mass was p resented in 12 cases, tumor with poorly defined margins in 2 cases, tumorous calcifications in 2 cases, involvement of retroperitoneal vessels in 2 cases, and invasion of retroperitoneal lymph nodes in 3 cases. None of the nephroblastoma invaded retrocrural lymph nodes. Irregular mass with calcifications, involvement of retroperitoneal vessels, retrocrural and retroperitoneal lymph nodes were more common in cases of neuroblastoma than in nephroblastoma. Moreover, involvement of retrocrural lymph nodes and encasement of retroperitoneal vessels had higher positive prediction value on neuroblastoma. Conclusion: Involvement of retrocrural lymph nodes and encasement of retroperitoneal vessels were the specific CT findings of neuroblastoma and the most valuable evidence in distinguishing neuroblastoma from nephroblastoma. (authors)

  17. Spatial pattern and scale influence invader demographic response to simulated precipitation change in an annual grassland community

    Science.gov (United States)

    It is important to predict which invasive species will benefit from future changes in climate, and thereby identify those invaders that need particular attention and prioritization of management efforts. Because establishment, persistence, and spread determine invasion success, this prediction requ...

  18. Short philtrum

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003302.htm Short philtrum To use the sharing features on this page, please enable JavaScript. A short philtrum is a shorter than normal distance between ...

  19. Contribution to the alien flora of Montenegro and Supplementum to the Preliminary list of plant invaders

    OpenAIRE

    Stešević, D.; Caković, D.

    2013-01-01

    This contribution is based on the field observations from 2011 to 2013. Besides new data about distribution of some known plant invaders, one new alien species for the flora of Montenegro is reported- Solidago gigantea. This plant was recorded in 2011, on two distinct localities near the road side in peri-urban area of Nikšić and Mojkovac, in the vicinity of gardens, were it has been grown as ornamental. In 2012 survey, species was again reported for Mojkovac, but it disappeared f...

  20. Recurrent malignant pilomatrixoma invading the cranial cavity: improved local control with adjuvant radiation

    International Nuclear Information System (INIS)

    Aherne, N. J.; Fitzpatrick, D. A.; Armstrong, J. G.; Gibbons, D.; Collins, C. D.

    2009-01-01

    Full text: We report the case of a 41-year-old mentally retarded male with recurrent pilomatrix carcinoma of the occipital region which invaded the occipital bone, left cerebellum and left temporal lobe. At his initial presentation the patient had a craniotomy and subtotal excision of the lesion with positive margins. He received no adjuvant therapy. After an early intracranial recurrence he had subtotal debulking and was referred for external beam radiotherapy. At 27 months follow-up after adjuvant external beam radiotherapy the intracranial component has not progressed and the patient remains clinically well

  1. Induction concurrent chemoradiation therapy for invading apical non-small cell lung cancer

    International Nuclear Information System (INIS)

    Miyoshi, Shinichiro; Nakamura, Kenji

    2004-01-01

    Although non-small cell lung cancer (NSCLC) involving the superior sulcus has been generally treated with radiation therapy (RT) followed by surgery, local recurrence is still a big problem to be solved. We investigated a role of induction therapy, especially induction concurrent chemoradiation therapy (CRT), on the surgical results of this type of NSCLC. We retrospectively reviewed 30 patients with NSCLC invading the apex of the chest wall who underwent surgery from 1987 to 1996. Ten patients (57±8 years) received surgery alone, 9 (55±13 years) received RT (42±7 Gy) followed by surgery and 11 (51±9 years) received cisplatin based chemotherapy and RT (47±5 Gy) as an induction therapy. Two and 4-year survival rates were 30% and 20% in patients with surgery alone, 22% and 11% in patients with induction RT, and 73% and 53% in patients with induction CRT, respectively. The survival was significantly better in patients with induction CRT than those with induction RT or surgery alone. Univariate analysis demonstrated that curability (yes versus no: p=0.027) and induction therapy (surgery alone and RT versus CRT: p=0.0173) were significant prognostic factors. Multivariate analysis revealed that only induction therapy (p=0.0238) was a significant prognostic factor. Induction CRT seems to improve the survival in patients with NSCLC invading the apex of the chest wall compared with induction RT or surgery alone. (author)

  2. Fungal endophytes which invade insect galls: insect pathogens, benign saprophytes, or fungal inquilines?

    Science.gov (United States)

    Wilson, Dennis

    1995-08-01

    Fungi are frequently found within insect galls. However, the origin of these fungi, whether they are acting as pathogens, saprophytes invading already dead galls, or fungal inquilines which invade the gall but kill the gall maker by indirect means, is rarely investigated. A pathogenic role for these fungi is usually inferred but never tested. I chose the following leaf-galling-insect/host-plant pairs (1) a cynipid which forms two-chambered galls on the veins of Oregon white oak, (2) a cynipid which forms single-chambered galls on California coast live oak, and (3) an aphid which forms galls on narrowleaf cottonwood leaves. All pairs were reported to have fungi associated with dead insects inside the gall. These fungi were cultured and identified. For the two cynipids, all fungi found inside the galls were also present in the leaves as fungal endophytes. The cottonwood leaves examined did not harbor fungal endophytes. For the cynipid on Oregon white oak, the fungal endophyte grows from the leaf into the gall and infects all gall tissue but does not directly kill the gall maker. The insect dies as a result of the gall tissue dying from fungal infection. Therefore, the fungus acts as an inquiline. Approximately 12.5% of these galls die as a result of invasion by the fungal endophyte.

  3. Integrating novel chemical weapons and evolutionarily increased competitive ability in success of a tropical invader.

    Science.gov (United States)

    Zheng, Yu-Long; Feng, Yu-Long; Zhang, Li-Kun; Callaway, Ragan M; Valiente-Banuet, Alfonso; Luo, Du-Qiang; Liao, Zhi-Yong; Lei, Yan-Bao; Barclay, Gregor F; Silva-Pereyra, Carlos

    2015-02-01

    The evolution of increased competitive ability (EICA) hypothesis and the novel weapons hypothesis (NWH) are two non-mutually exclusive mechanisms for exotic plant invasions, but few studies have simultaneously tested these hypotheses. Here we aimed to integrate them in the context of Chromolaena odorata invasion. We conducted two common garden experiments in order to test the EICA hypothesis, and two laboratory experiments in order to test the NWH. In common conditions, C. odorata plants from the nonnative range were better competitors but not larger than plants from the native range, either with or without the experimental manipulation of consumers. Chromolaena odorata plants from the nonnative range were more poorly defended against aboveground herbivores but better defended against soil-borne enemies. Chromolaena odorata plants from the nonnative range produced more odoratin (Eupatorium) (a unique compound of C. odorata with both allelopathic and defensive activities) and elicited stronger allelopathic effects on species native to China, the nonnative range of the invader, than on natives of Mexico, the native range of the invader. Our results suggest that invasive plants may evolve increased competitive ability after being introduced by increasing the production of novel allelochemicals, potentially in response to naïve competitors and new enemy regimes. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  4. Predicting how altering propagule pressure changes establishment rates of biological invaders across species pools.

    Science.gov (United States)

    Brockerhoff, Eckehard G; Kimberley, Mark; Liebhold, Andrew M; Haack, Robert A; Cavey, Joseph F

    2014-03-01

    Biological invasions resulting from international trade can cause major environmental and economic impacts. Propagule pressure is perhaps the most important factor influencing establishment, although actual arrival rates of species are rarely recorded. Furthermore, the pool of potential invaders includes many species that vary in their arrival rate and establishment potential. Therefore, we stress that it is essential to consider the size and composition of species pools arriving from source regions when estimating probabilities of establishment and effects of pathway infestation rates. To address this, we developed a novel framework and modeling approach to enable prediction of future establishments in relation to changes in arrival rate across entire species pools. We utilized 13 828 border interception records from the United States and New Zealand for 444 true bark beetle (Scolytinae) and longhorned beetle (Cerambycidae) species detected between 1949 and 2008 as proxies for arrival rates to model the relationship between arrival and establishment rates. Nonlinearity in this relationship implies that measures intended to reduce the unintended transport of potential invaders (such as phytosanitary treatments) must be highly effective in order to substantially reduce the rate of future invasions, particularly if trade volumes continue to increase.

  5. The role of adjuvant external beam radiation therapy for papillary thyroid carcinoma invading the trachea

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Suk; Choi, Jae Hyuck; Kim, Kwang Sik [Jeju National University Hospital, Jeju National University School of Medicine, Jeju (Korea, Republic of); and others

    2017-06-15

    To evaluate the effect of adjuvant external beam radiation therapy (EBRT) on local failure-free survival rate (LFFS) for papillary thyroid cancer (PTC) invading the trachea. Fifty-six patients with locally advanced PTC invading the trachea were treated with surgical resection. After surgery, 21 patients received adjuvant EBRT and radioactive iodine therapy (EBRT group) and 35 patients were treated with radioactive iodine therapy (control group). The age range was 26–87 years (median, 56 years). The median follow-up period was 43 months (range, 4 to 145 months). EBRT doses ranged from 50.4 to 66 Gy (median, 60 Gy). Esophagus invasion and gross residual disease was more frequent in the EBRT group. In the control group, local recurrence developed in 9 (9/35, 26%) and new distant metastasis in 2 (2/35, 6%) patients, occurring 4 to 68 months (median, 37 months) and 53 to 68 months (median, 60 months) after surgery, respectively. Two patients had simultaneous local recurrence and new distant metastasis. There was one local failure in the EBRT group at 18 months after surgery (1/21, 5%). The 5-year LFFS was 95% in the EBRT group and 63% in the control group (p = 0.103). In the EBRT group, one late grade 2 xerostomia was developed. Although, EBRT group had a higher incidence of esophagus invasion and gross residual disease, EBRT group showed a better 5-year LFFS. Adjuvant EBRT may have contributed to the better LFFS in these patients.

  6. Life History Variation in Invading Applesnails (Pomacea canaliculata) May Pose Ecological Threats to Wetlands

    Science.gov (United States)

    Marfurt, R. K.; Boland, B. B.; Burks, R. L.

    2005-05-01

    In native habitats, channeled applesnails (Pomacea canaliculata) graze periphyton. However, casual observations from introduced populations suggest these invaders show variation in feeding ecology, predator response and life history strategies. Attempts to predict this consumer influence on ecosystem function suffer from a lack of basic data. We tested how salinity affected snail mortality. Both adults and hatchlings tolerated salinity levels up to 8 ppt. Adult feeding on lettuce increased significantly at 8 ppt compared to 0 ppt (p = 0.002), while hatchling consumption of algae did not vary (p = 0.284). To see how these consumers responded to predators from the invaded ecosystem, we tested behavioural responses to predatory cues from fish, turtles, crayfish and adult applesnails. Results indicated that fish and crayfish prompted similar predator-avoidance behaviors in hatchlings (p's 0.05) between native (ramshorn) and exotic applesnails, whereas adult fish consumed more applesnails (x2, p < 0.001). Our current efforts focus on examining if predator presence or macrophyte choice alters applesnail feeding rates. Research providing insight into the basic ecology of applesnails can foster management efforts at the ecosystem scale.

  7. Invaders do not require high resource levels to maintain physiological advantages in a temperate deciduous forest.

    Science.gov (United States)

    Heberling, J Mason; Fridley, Jason D

    2016-04-01

    Non-native, invasive plants are commonly typified by trait strategies associated with high resource demands and plant invasions are often thought to be dependent upon site resource availability or disturbance. However, the invasion of shade-tolerant woody species into deciduous forests of the Eastern United States seems to contradict such generalization, as growth in this ecosystem is strongly constrained by light and, secondarily, nutrient stress. In a factorial manipulation of light and soil nitrogen availability, we established an experimental resource gradient in a secondary deciduous forest to test whether three common, woody, invasive species displayed increased metabolic performance and biomass production compared to six co-occurring woody native species, and whether these predicted differences depend upon resource supply. Using hierarchical Bayesian models of photosynthesis that included leaf trait effects, we found that invasive species exhibited functional strategies associated with higher rates of carbon gain. Further, invader metabolic and growth-related attributes were more responsive to increasing light availability than those of natives, but did not fall below average native responses even in low light. Surprisingly, neither group showed direct trait or growth responses to soil N additions. However, invasive species showed increased photosynthetic nitrogen use efficiencies with decreasing N availability, while that of natives remained constant. Although invader advantage over natives was amplified in higher resource conditions in this forest, our results indicate that some invasive species can maintain physiological advantages over co-occurring natives regardless of resource conditions.

  8. Propagule pressure, genetic structure, and geographic origins of Chondrilla juncea (Asteraceae): an apomictic invader on three continents.

    Science.gov (United States)

    Gaskin, John F; Schwarzländer, Mark; Kinter, C Lynn; Smith, James F; Novak, Stephen J

    2013-09-01

    Assessing propagule pressure and geographic origins of invasive species provides insight into the invasion process. Rush skeletonweed (Chondrilla juncea; Asteraceae) is an apomictic, perennial plant that is invasive in Australia, South America (Argentina), and North America (Canada and the United States). This study comprehensively compares propagule pressure and geographic structure of genotypes to improve our understanding of a clonal invasion and enhance management strategies. • We analyzed 1056 native range plants from Eurasia and 1156 plants from three invaded continents using amplified fragment length polymorphism (AFLP) techniques. We used measures of diversity (Simpson's D) and evenness (E), analysis of molecular variance, and Mantel tests to compare invasions, and genotype similarity to determine origins of invasive genotypes. • We found 682 unique genotypes in the native range, but only 13 in the invaded regions. Each invaded region contained distinct AFLP genotypes, suggesting independent introduction events, probably with different geographic origins. Relatively low propagule pressure was associated with each introduction around the globe, but levels of among-population variation differed. We found exact AFLP genotype matches between the native and invaded ranges for five of the 13 invasive genotypes. • Invasion dynamics can vary across invaded ranges within a species. Intensive sampling for molecular analyses can provide insight for understanding intraspecific invasion dynamics, which can hold significance for the management of plant species, especially by finding origins and distributions of invasive genotypes for classical biological control efforts.

  9. Facilitating the recovery of natural evergreen forests in South Africa via invader plant stands

    Directory of Open Access Journals (Sweden)

    Coert J. Geldenhuys

    2017-11-01

    Full Text Available Contrary to general belief, planted and naturalized stands of introduced species facilitate the recovery of natural evergreen forests and their diversity. Forest rehabilitation actions are often performed at great cost: mature forest species are planted, while species with adaptations to recover effectively and quickly after severe disturbance are ignored; or stands are cleared of invasive alien species before native tree species are planted. By contrast, cost-effective commercial plantation forestry systems generally use fast-growing pioneer tree species introduced from other natural forest regions. Such planted tree stands often facilitate the recovery of shade-tolerant native forest species. This paper provides a brief overview of disturbance-recovery processes at landscape level, and how pioneer stands of both native and introduced tree species develop from monocultures to diverse mature forest communities. It uses one example of a study of how natural forest species from small forest patches of 3 ha in total invaded a 90-ha stand of the invasive Black wattle, Acacia mearnsii, over a distance of 3.1 ha at Swellendam near Cape Town, South Africa. The study recorded 329 forest species clusters across the wattle stand: more large clusters closer to and more smaller clusters further away from natural forest patches. The 28 recorded forest species (of potentially 40 species in the surrounding forest patches included 79% tree and 21% shrub species. Colonizing forest species had mostly larger fleshy fruit and softer small seeds, and were dispersed by mostly birds and primate species. Maturing forest trees within developing clusters in the wattle stand became a source for forest regeneration away from the clusters, showing different expansion patterns. Four sets of fenced-unfenced plots in the wattle stand showed the impact of browsing by livestock, antelope, rodents and insects on the successful establishment of regenerating forest species, and the

  10. Listeria monocytogenes efficiently invades caco-2 cells after low-temperature storage in broth and on deli meat

    DEFF Research Database (Denmark)

    Larsen, Marianne Halberg; Koch, Anette Granly; Ingmer, Hanne

    2010-01-01

    The objective of this study was to investigate how various growth conditions influence the virulence of Listeria monocytogenes monitored by its ability to invade the epithelial cell lines Caco-2 and INT-407. The growth conditions examined were modified atmosphere-packaged deli meat and brain heart...... infusion broth (BHI) with and without salt. Five strains of L. monocytogenes were selected to investigate their invasiveness and all strains invaded Caco-2 cells at higher levels than INT-407 cells. Further, the clinical strains (3443 and 3734) were more invasive (p ... to invade Caco-2 cells was compared after growth on a fermented sausage and on cured cooked ham to that of bacteria grown in BHI broth supplemented with salt. Samples were stored under chilling conditions for up to 4 weeks. The results showed no difference (p > 0.05) in invasiveness after 7 days at 10...

  11. Inverted papilloma of lacrimal sac invading into the orbit: Case report and review of literature

    Directory of Open Access Journals (Sweden)

    Alistair W Hardy

    2015-01-01

    Full Text Available Inverted papilloma (IP is a sinonasal tumor of benign etiology with local invasion and malignant potential. IP arising in lacrimal sac invading the orbit is extremely rare with only one case reported so far. The presented case appears to be the second such case reported in the literature. A 60-year-old Caucasian male presented with a medial canthal mass and epiphora. Incisional biopsy confirmed a transitional neoplasm. The lesion was completely excised enbloc with clear margins by using a Weber-Ferguson incision; orbital clearance and nasolacrimalfossa clearance was achieved via a medial maxillectomy. Enbloc resection of orbital and nasolacrimal parts of the tumor with clear margins is recommended.

  12. Competitive helping increases with the size of biological markets and invades defection.

    Science.gov (United States)

    Barclay, Pat

    2011-07-21

    Cooperation between unrelated individuals remains a puzzle in evolutionary biology. Recent work indicates that partner choice can select for high levels of helping. More generally, helping can be seen as but one strategy used to compete for partners within a broader biological market, yet giving within such markets has received little mathematical investigation. In the present model, individuals help others to attract attention from them and thus receive a larger share of any help actively or passively provided by those others. The evolutionarily stable level of helping increases with the size of the biological market and the degree of partner choice. Furthermore, if individuals passively produce some no-cost help to partners, competitive helping can then invade populations of non-helpers because helpers directly benefit from increasing their access to potential partners. This framework of competitive helping demonstrates how high helping can be achieved and why different populations may differ in helping levels. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Control fast or control smart: When should invading pathogens be controlled?

    Directory of Open Access Journals (Sweden)

    Robin N Thompson

    2018-02-01

    Full Text Available The intuitive response to an invading pathogen is to start disease management as rapidly as possible, since this would be expected to minimise the future impacts of disease. However, since more spread data become available as an outbreak unfolds, processes underpinning pathogen transmission can almost always be characterised more precisely later in epidemics. This allows the future progression of any outbreak to be forecast more accurately, and so enables control interventions to be targeted more precisely. There is also the chance that the outbreak might die out without any intervention whatsoever, making prophylactic control unnecessary. Optimal decision-making involves continuously balancing these potential benefits of waiting against the possible costs of further spread. We introduce a generic, extensible data-driven algorithm based on parameter estimation and outbreak simulation for making decisions in real-time concerning when and how to control an invading pathogen. The Control Smart Algorithm (CSA resolves the trade-off between the competing advantages of controlling as soon as possible and controlling later when more information has become available. We show-using a generic mathematical model representing the transmission of a pathogen of agricultural animals or plants through a population of farms or fields-how the CSA allows the timing and level of deployment of vaccination or chemical control to be optimised. In particular, the algorithm outperforms simpler strategies such as intervening when the outbreak size reaches a pre-specified threshold, or controlling when the outbreak has persisted for a threshold length of time. This remains the case even if the simpler methods are fully optimised in advance. Our work highlights the potential benefits of giving careful consideration to the question of when to start disease management during emerging outbreaks, and provides a concrete framework to allow policy-makers to make this decision.

  14. Control fast or control smart: When should invading pathogens be controlled?

    Science.gov (United States)

    Thompson, Robin N; Gilligan, Christopher A; Cunniffe, Nik J

    2018-02-01

    The intuitive response to an invading pathogen is to start disease management as rapidly as possible, since this would be expected to minimise the future impacts of disease. However, since more spread data become available as an outbreak unfolds, processes underpinning pathogen transmission can almost always be characterised more precisely later in epidemics. This allows the future progression of any outbreak to be forecast more accurately, and so enables control interventions to be targeted more precisely. There is also the chance that the outbreak might die out without any intervention whatsoever, making prophylactic control unnecessary. Optimal decision-making involves continuously balancing these potential benefits of waiting against the possible costs of further spread. We introduce a generic, extensible data-driven algorithm based on parameter estimation and outbreak simulation for making decisions in real-time concerning when and how to control an invading pathogen. The Control Smart Algorithm (CSA) resolves the trade-off between the competing advantages of controlling as soon as possible and controlling later when more information has become available. We show-using a generic mathematical model representing the transmission of a pathogen of agricultural animals or plants through a population of farms or fields-how the CSA allows the timing and level of deployment of vaccination or chemical control to be optimised. In particular, the algorithm outperforms simpler strategies such as intervening when the outbreak size reaches a pre-specified threshold, or controlling when the outbreak has persisted for a threshold length of time. This remains the case even if the simpler methods are fully optimised in advance. Our work highlights the potential benefits of giving careful consideration to the question of when to start disease management during emerging outbreaks, and provides a concrete framework to allow policy-makers to make this decision.

  15. Red Lionfish (Pterois volitans Invade San Salvador, Bahamas: No Early Effects on Coral and Fish Communities

    Directory of Open Access Journals (Sweden)

    Alexander, Amanda K.

    2011-10-01

    Full Text Available Biological invaders are a leading contributor to global losses of biodiversity. A recent invader to the waters surrounding San Salvador, Bahamas, the red lionfish, Pterois volitans, was first reported in 2006; by 2009 they were common in waters 2-40 m deep around the island. Our study collected data on coral communities and fish assemblages at three patch reef complexes (Rice Bay, Rocky Point, Lindsay Reef in 2007, during the initial phase of the invasion, and compared the results to a nearly identical study done in 2001 before P. volitans colonized San Salvador. Prey selection and quantity of consumption by P. volitans were also examined. Coral and fish species richness, diversity, percent cover (corals and abundance (fish were similar in 2001 and 2007. Of the 5,078 fish recorded during our study on shallow patch reefs, only two were P. volitans, but they were more prevalent in deeper water along San Salvador’s “wall.” Captured P. volitans ranged in size from 19-32 cm, all longer than maturity length. Pallid goby (Coryphopterus eidolon, black cap basslet (Gramma melacara and red night shrimp (Rynchocienetes rigens were the most commonly identified stomach contents. The effects of the successful invasion and increasing population of P. volitans on San Salvador’s reef ecosystem are uncertain at this time; future monitoring of potential changes in coral and fish communities on the patch reefs of San Salvador is recommended to determine if population control measures need to be considered. Initial post-invasion data (2007, along with pre-invasion data (2001, are valuable benchmarks for future studies.

  16. Stoichiometric constraints do not limit successful invaders: zebra mussels in Swedish lakes.

    Science.gov (United States)

    Naddafi, Rahmat; Eklöv, Peter; Pettersson, Kurt

    2009-01-01

    Elemental imbalances of carbon (C): nitrogen (N): phosphorus (P) ratios in food resources can constrain the growth of grazers owning to tight coupling between growth rate, RNA allocation and biomass P content in animals. Testing for stoichiometric constraints among invasive species is a novel challenge in invasion ecology to unravel how a successful invader tackles ecological barriers in novel ecosystems. We examined the C:P and N:P ratios and the condition factor of a successful invader in lakes, the zebra mussel (Dreissena polymorpha), collected from two Swedish lakes. Concurrently, we analyzed the elemental composition of the food (seston) and tissue of the mussels in which nutrient composition of food and mussels varied over time. Zebra mussel condition factor was weakly related to the their own tissue N:P and C:P ratios, although the relation with the later ratio was not significant. Smaller mussels had relatively lower tissue N:P ratio and higher condition factor. There was no difference in C:P and N:P ratios between seston and mussels' tissues. Our results indicated that the variation in nutrient stoichiometry of zebra mussels can be explained by food quality and quantity. Our study suggests that fitness of invasive zebra mussels is not constrained by nutrient stoichiometry which is likely to be important for their proliferation in novel ecosystems. The lack of imbalance in C:P and N:P ratios between seston and mussels along with high tissue C:P ratio of the mussel allow them to tolerate potential P limitation and maintain high growth rate. Moreover, zebra mussels are able to change their tissue C:P and N:P ratios in response to the variation in elemental composition of their food. This can also help them to bypass potential nutrient stoichiometric constraints. Our finding is an important step towards understanding the mechanisms contributing to the success of exotic species from stoichiometric principles.

  17. Stoichiometric constraints do not limit successful invaders: zebra mussels in Swedish lakes.

    Directory of Open Access Journals (Sweden)

    Rahmat Naddafi

    Full Text Available Elemental imbalances of carbon (C: nitrogen (N: phosphorus (P ratios in food resources can constrain the growth of grazers owning to tight coupling between growth rate, RNA allocation and biomass P content in animals. Testing for stoichiometric constraints among invasive species is a novel challenge in invasion ecology to unravel how a successful invader tackles ecological barriers in novel ecosystems.We examined the C:P and N:P ratios and the condition factor of a successful invader in lakes, the zebra mussel (Dreissena polymorpha, collected from two Swedish lakes. Concurrently, we analyzed the elemental composition of the food (seston and tissue of the mussels in which nutrient composition of food and mussels varied over time. Zebra mussel condition factor was weakly related to the their own tissue N:P and C:P ratios, although the relation with the later ratio was not significant. Smaller mussels had relatively lower tissue N:P ratio and higher condition factor. There was no difference in C:P and N:P ratios between seston and mussels' tissues. Our results indicated that the variation in nutrient stoichiometry of zebra mussels can be explained by food quality and quantity.Our study suggests that fitness of invasive zebra mussels is not constrained by nutrient stoichiometry which is likely to be important for their proliferation in novel ecosystems. The lack of imbalance in C:P and N:P ratios between seston and mussels along with high tissue C:P ratio of the mussel allow them to tolerate potential P limitation and maintain high growth rate. Moreover, zebra mussels are able to change their tissue C:P and N:P ratios in response to the variation in elemental composition of their food. This can also help them to bypass potential nutrient stoichiometric constraints. Our finding is an important step towards understanding the mechanisms contributing to the success of exotic species from stoichiometric principles.

  18. Linking Native and Invader Traits Explains Native Spider Population Responses to Plant Invasion.

    Directory of Open Access Journals (Sweden)

    Jennifer N Smith

    Full Text Available Theoretically, the functional traits of native species should determine how natives respond to invader-driven changes. To explore this idea, we simulated a large-scale plant invasion using dead spotted knapweed (Centaurea stoebe stems to determine if native spiders' web-building behaviors could explain differences in spider population responses to structural changes arising from C. stoebe invasion. After two years, irregular web-spiders were >30 times more abundant and orb weavers were >23 times more abundant on simulated invasion plots compared to controls. Additionally, irregular web-spiders on simulated invasion plots built webs that were 4.4 times larger and 5.0 times more likely to capture prey, leading to >2-fold increases in recruitment. Orb-weavers showed no differences in web size or prey captures between treatments. Web-spider responses to simulated invasion mimicked patterns following natural invasions, confirming that C. stoebe's architecture is likely the primary attribute driving native spider responses to these invasions. Differences in spider responses were attributable to differences in web construction behaviors relative to historic web substrate constraints. Orb-weavers in this system constructed webs between multiple plants, so they were limited by the overall quantity of native substrates but not by the architecture of individual native plant species. Irregular web-spiders built their webs within individual plants and were greatly constrained by the diminutive architecture of native plant substrates, so they were limited both by quantity and quality of native substrates. Evaluating native species traits in the context of invader-driven change can explain invasion outcomes and help to identify factors limiting native populations.

  19. Short communication

    African Journals Online (AJOL)

    abp

    2017-09-04

    Sep 4, 2017 ... Face-to-face interviews were conducted using a standardized ... Short communication. Open Access ... clinic during the time of the study and were invited to participate in the study. .... consume them. This is another ...

  20. SHORT COMMUNICATION

    African Journals Online (AJOL)

    PROF P.T. KAYE

    . SHORT COMMUNICATION. Formation and Structural Analysis of Novel Dibornyl Ethers. Perry T. Kaye*, Andrew R. Duggan, Joseph M. Matjila, Warner E. Molema, and. Swarnam S. Ravindran. Department of Chemistry, Rhodes University, Grahamstown, ...

  1. The impact of failure: unsuccessful bacterial invasions steer the soil microbial community away from the invader's niche.

    Science.gov (United States)

    Mallon, C A; Le Roux, X; van Doorn, G S; Dini-Andreote, F; Poly, F; Salles, J F

    2018-03-01

    Although many environments like soils are constantly subjected to invasion by alien microbes, invaders usually fail to succeed, succumbing to the robust diversity often found in nature. So far, only successful invasions have been explored, and it remains unknown to what extent an unsuccessful invasion can impact resident communities. Here we hypothesized that unsuccessful invasions can cause impacts to soil functioning by decreasing the diversity and niche breadth of resident bacterial communities, which could cause shifts to community composition and niche structure-an effect that is likely exacerbated when diversity is compromised. To examine this question, diversity gradients of soil microbial communities were subjected to invasion by the frequent, yet oft-unsuccessful soil invader, Escherichia coli, and evaluated for changes to diversity, bacterial community composition, niche breadth, and niche structure. Contrary to expectations, diversity and niche breadth increased across treatments upon invasion. Community composition and niche structure were also altered, with shifts of niche structure revealing an escape by the resident community away from the invader's resources. Importantly, the extent of the escape varied in response to the community's diversity, where less diverse communities experienced larger shifts. Thus, although transient and unsuccessful, the invader competed for resources with resident species and caused tangible impacts that modified both the diversity and functioning of resident communities, which can likely generate a legacy effect that influences future invasion attempts.

  2. Darwin's naturalization hypothesis up-close: Intermountain grassland invaders differ morphologically and phenologically from native community dominants

    Science.gov (United States)

    Dean E. Pearson; Yvette K. Ortega; Samantha J. Sears

    2012-01-01

    Darwin's naturalization hypothesis predicts that successful invaders will tend to differ taxonomically from native species in recipient communities because less related species exhibit lower niche overlap and experience reduced biotic resistance. This hypothesis has garnered substantial support at coarse scales. However, at finer scales, the influence of traits...

  3. Relative roles of climatic suitability and anthropogenic influence in determining the pattern of spread in a global invader

    DEFF Research Database (Denmark)

    Roura-Pascual, Núria; Hui, Cang; Ikeda, Takayoshi

    2011-01-01

    Because invasive species threaten the integrity of natural ecosystems, a major goal in ecology is to develop predictive models to determine which species may become widespread and where they may invade. Indeed, considerable progress has been made in understanding the factors that influence the lo...

  4. Persistence of Native Trees in an Invaded Hawaiian Lowland Wet Forest: Experimental Evaluation of Light and Water Constraints

    Science.gov (United States)

    Jodie R. Schulten; T. Colleen Cole; Susan Cordell; Keiko M. Publico; Rebecca Ostertag; Jaime E. Enoka; Jené D. Michaud

    2014-01-01

    Hawaiian lowland wet forests are heavily invaded and their restoration is most likely to be successful if native species selected for restoration have efficient resource-use traits. We evaluated growth, survival, and ecophysiological responses of four native and four invasive species in a greenhouse experiment that simulated reduced light and water conditions commonly...

  5. A contribution to improved radiotherapy for muscle invading urinary bladder cancer

    Energy Technology Data Exchange (ETDEWEB)

    Muren, Ludvig PAul

    2002-07-01

    Cystectomy has traditionally been regarded the treatment of choice for muscle invading urinary bladder cancer in most countries. Radiotherapy has been offered patients considered unfit for cystectomy. Since the contraindications of surgery are frequent among bladder cancer patients, a substantial amount of patients with muscle invading bladder cancer (typically 50%) are still managed primarily with radiation. Recently, a tri-modality, organsparing treatment (trans-urethral resection and radio-chemotherapy) has been proposed for bladder cancer, like in the management of a range of other common malignancies. This approach may provide as high control rates as cystectomy yet maintain a higher quality of life for selected patient groups. In both the radical radiotherapy and the combined modality approach, high radiation doses are needed to improve local disease control. Radiation dose escalation requires improved conformation of dose distributions. This PhD programme aimed to develop improved conformal radiotherapy procedures in the management of patients with muscle invading urinary bladder cancer. In the initial phase of this work, computer-controlled movement of the linear accelerator collimator jaws during beam delivery was applied to shape so-called partially wedged beams (PWBs), that were designed specifically to tailor the dose distribution in bladder irradiation closer to the defined bladder target. The dosimetric verification and treatment planning implementation of this beam delivery concept were addressed, and we documented that these dynamic beams were delivered as accurately as standard beams. Particular attention was given to the BMS-96 diode array system, as it was adapted to dynamic beam dosimetry. Next, the potential clinical impact of these beams was analysed. In a retrospectively study of a set of urinary bladder treatment plans, the PWBs were seen to improve the dose homogeneity inside the bladder target as well as to reduce normal tissue (small

  6. A contribution to improved radiotherapy for muscle invading urinary bladder cancer

    International Nuclear Information System (INIS)

    Muren, Ludvig PAul

    2002-01-01

    Cystectomy has traditionally been regarded the treatment of choice for muscle invading urinary bladder cancer in most countries. Radiotherapy has been offered patients considered unfit for cystectomy. Since the contraindications of surgery are frequent among bladder cancer patients, a substantial amount of patients with muscle invading bladder cancer (typically 50%) are still managed primarily with radiation. Recently, a tri-modality, organsparing treatment (trans-urethral resection and radio-chemotherapy) has been proposed for bladder cancer, like in the management of a range of other common malignancies. This approach may provide as high control rates as cystectomy yet maintain a higher quality of life for selected patient groups. In both the radical radiotherapy and the combined modality approach, high radiation doses are needed to improve local disease control. Radiation dose escalation requires improved conformation of dose distributions. This PhD programme aimed to develop improved conformal radiotherapy procedures in the management of patients with muscle invading urinary bladder cancer. In the initial phase of this work, computer-controlled movement of the linear accelerator collimator jaws during beam delivery was applied to shape so-called partially wedged beams (PWBs), that were designed specifically to tailor the dose distribution in bladder irradiation closer to the defined bladder target. The dosimetric verification and treatment planning implementation of this beam delivery concept were addressed, and we documented that these dynamic beams were delivered as accurately as standard beams. Particular attention was given to the BMS-96 diode array system, as it was adapted to dynamic beam dosimetry. Next, the potential clinical impact of these beams was analysed. In a retrospectively study of a set of urinary bladder treatment plans, the PWBs were seen to improve the dose homogeneity inside the bladder target as well as to reduce normal tissue (small

  7. Short Stature

    DEFF Research Database (Denmark)

    Christesen, Henrik Boye Thybo; Pedersen, Birgitte Tønnes; Pournara, Effie

    2016-01-01

    -scale, non-interventional, multinational study. The patient cohort consisted of 5996 short pediatric patients diagnosed with growth hormone deficiency (GHD), Turner syndrome (TS) or born small for gestational age (SGA). The proportions of children with baseline height standard deviation score (SDS) below......The use of appropriate growth standards/references is of significant clinical importance in assessing the height of children with short stature as it may determine eligibility for appropriate therapy. The aim of this study was to determine the impact of using World Health Organization (WHO) instead...... of national growth standards/references on height assessment in short children. Data were collected from routine clinical practice (1998-2014) from nine European countries that have available national growth references and were enrolled in NordiNet® International Outcome Study (IOS) (NCT00960128), a large...

  8. Using a prescribed fire to test custom and standard fuel models for fire behaviour prediction in a non-native, grass-invaded tropical dry shrubland

    Science.gov (United States)

    Andrew D. Pierce; Sierra McDaniel; Mark Wasser; Alison Ainsworth; Creighton M. Litton; Christian P. Giardina; Susan Cordell; Ralf Ohlemuller

    2014-01-01

    Questions: Do fuel models developed for North American fuel types accurately represent fuel beds found in grass-invaded tropical shrublands? Do standard or custom fuel models for firebehavior models with in situ or RAWS measured fuel moistures affect the accuracy of predicted fire behavior in grass-invaded tropical shrublands? Location: Hawai’i Volcanoes National...

  9. Short Review

    DEFF Research Database (Denmark)

    Lynnerup, Niels; Rühli, Frank

    2015-01-01

    modality in ancient mummy research. The aim of this short review is to address the advantages and pitfalls of this particular technique for such unique samples. We recommend that when results of X-ray examination of mummies are presented, the specific recording data should be listed, and any given finds...

  10. Short fusion

    CERN Multimedia

    2002-01-01

    French and UK researchers are perfecting a particle accelerator technique that could aid the quest for fusion energy or make X-rays that are safer and produce higher-resolution images. Led by Dr Victor Malka from the Ecole Nationale Superieure des Techniques Avancees in Paris, the team has developed a better way of accelerating electrons over short distances (1 page).

  11. Short communication

    African Journals Online (AJOL)

    UPuser

    Short communication. Polymorphisms of the CAST gene in the Meishan and five other pig populations in China. Q.S. Wang. 1. , Y.C. Pan. 1#. , L.B. Sun. 2 and H. Meng. 1. 1 Department of Animal Science, School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai. 201101, P.R. China. 2 Shanghai Institute of ...

  12. SHORT COMMUNICATION

    African Journals Online (AJOL)

    a

    ______. *Corresponding author. E-mail: vani_chem@yahoo.com. SHORT COMMUNICATION. OXIDATION OF L-CYSTINE BY CHROMIUM(VI) - A KINETIC STUDY. Kalyan Kumar Adari, Annapurna Nowduri and Vani Parvataneni*. Department of Inorganic and Analytical Chemistry, School of Chemistry, Andhra University,.

  13. Short communication

    NARCIS (Netherlands)

    Pantophlet, Andre J.; Gilbert, M.S.; Gerrits, W.J.J.; Vonk, R.J.

    2017-01-01

    Heavy veal calves (4-6 mo old) often develop problems with insulin sensitivity. This could lead to metabolic disorders and impaired animal growth performance. Studies in various animal species have shown that the supplementation of short-chain fructo-oligosaccharides (scFOS) can improve insulin

  14. USE OF UAV PLATFORM AS AN AUTONOMOUS TOOL FOR ESTIMATING EXPANSION ON INVADED AGRICULTURAL LAND

    Directory of Open Access Journals (Sweden)

    Niarkios Luiz Santos de Salles Graça

    Full Text Available Abstract: For a long time, in many countries, questions involving disputes about land ownership has generated demand for geoinformation and documentation. In most cases, access for researchers is restricted or humanely impossible by eminence of conflicts, even armed. In these cases, researchers use Remote Sensing and Photogrammetry to enable their studies. However, the dynamics of the phenomenon being studied often requires approaches that traditional techniques become unviable or unable to fulfil. This work shows the results of an approach that used a photogrammetric UAV platform to take pictures of an invaded rural area in Brazil and estimate its expansion over two years. From the taken images, mosaics were generated and then classified using Decision Tree to identify tents. Then it was developed a Matlab algorithm, to detect and quantify the tents on the classified Images. It was possible to infer that there was an expansion of 7.3% between the two analyzed dates and probably more than three thousand people occupied the invasion site.

  15. Mechanical properties of metastatic breast cancer cells invading into collagen I matrices

    Science.gov (United States)

    Ros, Robert

    2014-03-01

    Mechanical interactions between cells and the extracellular matrix (ECM) are critical to the metastasis of cancer cells. To investigate the mechanical interplay between the cells and ECM during invasion, we created thin bovine collagen I hydrogels ranging from 0.1-5 kPa in Young's modulus that were seeded with highly metastatic MDA-MB-231 breast cancer cells. Significant population fractions invaded the matrices either partially or fully within 24 h. We then combined confocal fluorescence microscopy and indentation with an atomic force microscope to determine the Young's moduli of individual embedded cells and the pericellular matrix using novel analysis methods for heterogeneous samples. In partially embedded cells, we observe a statistically significant correlation between the degree of invasion and the Young's modulus, which was up to an order of magnitude greater than that of the same cells measured in 2D. ROCK inhibition returned the cells' Young's moduli to values similar to 2D and diminished but did not abrogate invasion. This provides evidence that Rho/ROCK-dependent acto-myosin contractility is employed for matrix reorganization during initial invasion, and suggests the observed cell stiffening is due to an attendant increase in actin stress fibers. This work was supported by the National Cancer Institute under the grant U54 CA143862.

  16. Alien roadside species more easily invade alpine than lowland plant communities in a subarctic mountain ecosystem.

    Directory of Open Access Journals (Sweden)

    Jonas J Lembrechts

    Full Text Available Effects of roads on plant communities are not well known in cold-climate mountain ecosystems, where road building and development are expected to increase in future decades. Knowledge of the sensitivity of mountain plant communities to disturbance by roads is however important for future conservation purposes. We investigate the effects of roads on species richness and composition, including the plant strategies that are most affected, along three elevational gradients in a subarctic mountain ecosystem. We also examine whether mountain roads promote the introduction and invasion of alien plant species from the lowlands to the alpine zone. Observations of plant community composition were made together with abiotic, biotic and anthropogenic factors in 60 T-shaped transects. Alpine plant communities reacted differently to road disturbances than their lowland counterparts. On high elevations, the roadside species composition was more similar to that of the local natural communities. Less competitive and ruderal species were present at high compared with lower elevation roadsides. While the effects of roads thus seem to be mitigated in the alpine environment for plant species in general, mountain plant communities are more invasible than lowland communities. More precisely, relatively more alien species present in the roadside were found to invade into the surrounding natural community at high compared to low elevations. We conclude that effects of roads and introduction of alien species in lowlands cannot simply be extrapolated to the alpine and subarctic environment.

  17. Alien roadside species more easily invade alpine than lowland plant communities in a subarctic mountain ecosystem.

    Science.gov (United States)

    Lembrechts, Jonas J; Milbau, Ann; Nijs, Ivan

    2014-01-01

    Effects of roads on plant communities are not well known in cold-climate mountain ecosystems, where road building and development are expected to increase in future decades. Knowledge of the sensitivity of mountain plant communities to disturbance by roads is however important for future conservation purposes. We investigate the effects of roads on species richness and composition, including the plant strategies that are most affected, along three elevational gradients in a subarctic mountain ecosystem. We also examine whether mountain roads promote the introduction and invasion of alien plant species from the lowlands to the alpine zone. Observations of plant community composition were made together with abiotic, biotic and anthropogenic factors in 60 T-shaped transects. Alpine plant communities reacted differently to road disturbances than their lowland counterparts. On high elevations, the roadside species composition was more similar to that of the local natural communities. Less competitive and ruderal species were present at high compared with lower elevation roadsides. While the effects of roads thus seem to be mitigated in the alpine environment for plant species in general, mountain plant communities are more invasible than lowland communities. More precisely, relatively more alien species present in the roadside were found to invade into the surrounding natural community at high compared to low elevations. We conclude that effects of roads and introduction of alien species in lowlands cannot simply be extrapolated to the alpine and subarctic environment.

  18. Invading species in the Eel River, California: Successes, failures, and relationships with resident species

    Science.gov (United States)

    Brown, L.R.; Moyle, P.B.

    1997-01-01

    We examined invasions of non-native fishes into the Eel River, California. At least 16 species of fish have been introduced into the drainage which originally supported 12-14 fish species. Our study was prompted by the unauthorized introduction in 1979 of Sacramento squawfish, Ptychocheilus grandis, a large predatory cyprinid. From 1986 to 1990, we conducted growth and diet studies of squaw fish, conducted intensive surveys of the distribution and habitat associations of both native and introduced species, and examined the nature of species-habitat and interspecies relationships. We found no evidence for increased growth or expanded feeding habits, compared to native populations, of Sacramento squawfish as they invaded the Eel River drainage. Ten of the introduced species were well established, with four species limited to a reservoir and six species established in streams. The success or failure of introductions of stream species appeared to be a function of the ability of a species to survive the fluctuating, highly seasonal, flow regime. The present mixture of native and exotic species has not formed stable fish assemblages but it seems likely that four habitat-associated assemblages will develop. The overall effect of the successful species introductions has been to assemble a group of species, with some exceptions, that are native to and occur together in many California streams. The assemblages now forming are similar to those found in other California streams. The assemblage characterized by squawfish and suckers is likely to be resistant to invasion, in the absence of human caused habitat modifications.

  19. Irradiation effects for the growth inhibition of weed seeds invaded from foreign countries

    International Nuclear Information System (INIS)

    Takatani, Yasuyuki; Ito, Hitoshi

    1999-01-01

    Weeds of foreign origin have been invaded through imported maize or dried grass which using for animal feeds, and causing serious damages to agricultural crops and farm animals in Japan. These weeds are spreading mainly through animal feeds to feces. For the purpose to decrease the damage from these weeds, we investigated the gamma-irradiation effect on 7 species of the weed seed to suppress the germination or elongation of stem and root. After the irradiation of the weed seeds, all species kept the ability of germination even at 4 kGy in petri dish cultivation, whereas decreased the germination ratio in some species. However, many species of weed decreased the ability on elongation of stem or root below l kGy irradiation. Furthermore, all of species lost the ability on the development of root hair and appearance of first leaf after germination of seeds below 1 kGy irradiation. From this study, necessary dose for growth inhibition was estimated to be 1 kGy which should be able to apply with combination treatment of the animal feeds for elimination of pathogenic bacteria such as salmonellae at 3 to 5 kGy irradiation. (author)

  20. Herbivory more limiting than competition on early and established native plants in an invaded meadow.

    Science.gov (United States)

    Gonzales, Emily K; Arcese, Peter

    2008-12-01

    The dominance of nonnative plants coupled with declines of native plants suggests that competitive displacement drives extinctions, yet empirical examples are rare. Herbivores, however, can alter vegetation structure and reduce diversity when abundant. Herbivores may act on mature, reproductive life stages whereas some of the strongest competitive effects might occur at early life stages that are difficult to observe. For example, competition by perennial nonnative grasses can interfere with the establishment of native seeds. We contrasted the effects of ungulate herbivory and competition by neighboring plants on the performance of native plant species at early and established life stages in invaded oak meadows. We recorded growth, survival, and flowering in two native species transplanted as established plants, six native species grown from seed, and five extant lily species as part of two 2 x 2 factorial experiments that manipulated herbivory and competition. Herbivory reduced the performance of nearly all focal native species at early and established life stages, whereas competition had few measurable effects. Our results suggest that herbivory has a greater local influence on native plant species than competition and that reducing herbivore impacts will be required to successfully restore endangered oak meadows where ungulates are now abundant.

  1. Management of invading pathogens should be informed by epidemiology rather than administrative boundaries.

    Science.gov (United States)

    Thompson, Robin N; Cobb, Richard C; Gilligan, Christopher A; Cunniffe, Nik J

    2016-03-24

    Plant and animal disease outbreaks have significant ecological and economic impacts. The spatial extent of control is often informed solely by administrative geography - for example, quarantine of an entire county or state once an invading disease is detected - with little regard for pathogen epidemiology. We present a stochastic model for the spread of a plant pathogen that couples spread in the natural environment and transmission via the nursery trade, and use it to illustrate that control deployed according to administrative boundaries is almost always sub-optimal. We use sudden oak death (caused by Phytophthora ramorum ) in mixed forests in California as motivation for our study, since the decision as to whether or not to deploy plant trade quarantine is currently undertaken on a county-by-county basis for that system. However, our key conclusion is applicable more generally: basing management of any disease entirely upon administrative borders does not balance the cost of control with the possible economic and ecological costs of further spread in the optimal fashion.

  2. Northward invading non-native vascular plant species in and adjacent to Wood Buffalo National Park

    Energy Technology Data Exchange (ETDEWEB)

    Wein, R.W.; Wein, G.; Bahret, S.; Cody, W.J. (Alberta University, Edmonton, AB (Canada). Canadian Circumpolar Institute)

    A survey of the non-native vascular plant species in Wood Buffalo National Park, Canada's largest forested National Park, documented their presence and abundance in key locations. Most of the fifty-four species (nine new records) were found in disturbed sites including roadsides, settlements, farms, areas of altered hydrological regimes, recent bums, and intensive bison grazing. Species that have increased most in geographic area and abundance in recent years include [ital Agropyron repens], [ital Bromus inermis], [ital Chenopodium album], [ital Melilotus spp.], [ital Trifolium spp.], [ital Plantago major], [ital Achillea millefolium], [ital Crepis tectorum] and [ital Sonchus arvensis]. An additional 20 species, now common in the Peace River and Fort Vermilion areas, have the potential to invade the Park if plant communities are subjected to additional stress as northern climates are modified by the greenhouse effect and as other human-caused activities disturb the vegetation. It is recommended that permanent plots be located in key locations and monitored for species invasion and changing abundances as input to management plans.

  3. Short Communication

    African Journals Online (AJOL)

    huis

    Short Communication. QTL analysis of production traits on SSC3 in a Large White×Meishan pig resource family. B. Zuo. 1. , Y.Z. Xiong. 1#. , Y.H. Su. 2. , C.Y. Deng. 1. , M.G. Lei. 1. , F.E. Li. 1. , R. Zheng. 1 and S.W. Jiang. 1. 1 Key Laboratory of Swine Genetics and Breeding, Ministry of Agriculture & Key Lab of Agricultural ...

  4. CT differentiation of renal tumor invading parenchyma and pelvis: renal cell carcinoma vs transitional cell carcinoma

    International Nuclear Information System (INIS)

    Lee, Chang Hee; Cho, Seong Beum; Park, Cheol Min; Cha, In Ho; Chung, Kyoo Byung

    1994-01-01

    The differentiation between renal cell carcinoma(RCC) and transitional cell carcinoma(TCC) is important due to the different methods of treatment and prognosis. But occasionally it is difficult to draw a distinction between the two diseases when renal parenchyma and renal collecting systems are invaded simultaneously. We reviewed CT scans of 37 cases of renal cell carcinoma and 12 cases of transitional cell carcinoma which showed involvement of renal parenchyma and renal sinus fat on CT. Retrospective analysis was performed by 3 abdominal radiologists. Check points were renal contour bulging or reinform shape, location of mass center, intact parenchyma overlying the tumor, cystic change, calcification, LN metastasis, vessel invasion, and perirenal extention. There were renal contour bulging due to the tumor mass in 33 out of 37 cases of renal cell carcinoma, where a and nine of 12 cases of transitional cell carcinoma maintained the reinform appearance. This is significant statiscal difference between the two(P<0.005). Center of all TCCs were located in the renal sinus, and 24 out of 35 cases of RCC were located in the cortex(P<0.005). Thirty-six out of 37 cases of RCC lost the overlying parenchyma, where as 4 out of 9 cases of well enhanced TCC had intact overlying parenchyma(P<0.005) RCC showed uptic change within the tumor mags in 31 cases which was significanity higher than the 4 cases in TCC(P<0.05). CT findings of renal cell carcinoma are contour bulging, peripheral location, obliteration of parenchyma, and cystic change. Findings of transitional cell carcinoma are reinform appearance, central location within the kidney, intact overlying parenchyma, and rare cystic change

  5. Alien plants in urban nature reserves: from red-list species to future invaders?

    Directory of Open Access Journals (Sweden)

    Vojtěch Jarošik

    2011-10-01

    Full Text Available Urban reserves, as other protected areas, are aimed at preserving species richness but the conservation effort in these protected areas is complicated by a high proportion of alien species. We examined which environmental factors determine the representation of alien species in 48 city reserves of Prague, Czech Republic, distinguishing between archaeophytes, i.e. alien species introduced since the beginning of Neolithic agriculture up to 1500 A. D., and neophytes, i.e. modern invaders introduced after that date, with the former group separately analysed for endangered archaeophytes (listed as C1 and C2 categories on national red list. Archaeophytes responded positively to the extent of arable land that was in place at the time of the reserve establishment, and to a low altitudinal range. Neophytes, beside soil properties responded to recent human activities proxied by current proportion of built-up area in the reserves. Endangered archaeophytes, besides the same affinity for past arable land as other archaeophytes, were supported by the presence of current wasteland habitats in the reserve. This suggests that for endangered archaeophytes it might have been difficult to adapt to changing agricultural practices, and ruderal wasteland might act as a refugium for them. From the viewpoint of conservation, ruderal habitats of nature reserves thus can be more important than was previously though. Forty-six of the 155 neophytes recorded in the reserves are classified as invasive. The reserves thus harbour 67% of the 69 invasive neophytes recorded in the country, and particularly warning is that among the most invasive species are many shrubs and trees, a life form that is known to account for widespread invasions with high impacts. Our results thus strongly suggest that in Prague nature reserves there is a warning potential for future invasions.

  6. Generalist dispersers promote germination of an alien fleshy-fruited tree invading natural grasslands.

    Directory of Open Access Journals (Sweden)

    Martín Raúl Amodeo

    Full Text Available Plants with animal-dispersed fruits seem to overcome the barriers that limit their spread into new habitats more easily than other invasive plants and, at the same time, they pose special difficulties for containment, control or eradication. The effects of animals on plant propagules can be very diverse, with positive, neutral or negative consequences for germination and recruitment. Moreover, the environmental conditions where the seeds are deposited and where the post-dispersal processes take place can be crucial for their fate. Prunus mahaleb is a fleshy-fruited tree invading natural grasslands in the Argentine Pampas. In this study, we analyzed the importance of pulp removal, endocarp scarification and the effects of vectors on its germination response, by means of germination experiments both in the laboratory and under semi-natural conditions. Our laboratory results demonstrated that endocarp scarification enhances germination and suggests that vestiges of pulp on the stones have inhibitory effects. Frugivores exert a variety of effects on germination responses and this variation can be explained by their differing influence on pulp removal and endocarp scarification. Most frugivores produced a positive effect on germination under laboratory conditions, in comparison to intact fruits and hand-peeled stones. We observed different degrees of pulp removal from the surface of the stones by the dispersers which was directly correlated to the germination response. On the other hand, all the treatments showed high germination responses under semi-natural conditions suggesting that post-dispersal processes, like seed burial, and the exposure to natural conditions might exert a positive effect on germination response, attenuating the plant's dependence on the dispersers' gut treatment. Our results highlight the need to consider the whole seed dispersal process and the value of combining laboratory and field tests.

  7. Intraperitoneal ectopic infestation of parasites invading through gastrointestinal tract : CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jeong Kon; Rha, Sung Eun; Ha, Hyun Kwon; Kim, Pyo Nyun; Lee, Moon Gyu; Auh, Yong Ho [Asan Medical Center, Ulsan Univ., Ulsan (Korea, Republic of); Choi, Byung Ihn [Seoul National Univ. College of Medicine, Seoul (Korea, Republic of); Shim, Jae Chul [Inje Univ. College of Medicine, Kimhae (Korea, Republic of); Kim, Hyun [St. Mary' s Hospital, The Catholic Univ. of Korea, Seoul (Korea, Republic of); Lee, Jong Hwa; Ham, Soo Youn [Ulsan Univ. Hospital, Ulsan (Korea, Republic of)

    1999-03-01

    The purpose of this study was to evaluate the CT findings of parasitic ectopic infestation in the peritoneal cavity, a transitional route for parasites invading the gastrointestinal tract, to migrate to various target organs. CT scans of nine patients with pathologically(n=8) or serologically(n=1) proven intraperitoneal involvement of parasitic infestation were retrospectively reviewed. The primary causes of parasitic infestation in nine patients were Paragonimus westermani(n=5), Sparganosis(n=2), and hepatic fascioliasis(n=2). We analyzed the CT findings with regard to the sites and patterns of lesions in the peritoneal cavity and gastrointestinal track, as well as in other solid organs. The clinical features of these patients were also evaluated. The clinical symptoms and signs were chronic abdominal pain and general weakness in seven patients, while peripheral blood eosinophilia was observed in four. The CT features of these nine patients included multiseptated cystic masses of 2-6cm, diameter (mean 4.1{+-}1.7cm) in the omentum or mesentery in six(67%), omental or mesenteric infiltration in seven(78%), focal peritoneal thickening in seven(78%), 1ymphadenopathy in five(56%), and ascites in four(44%). In six of the nine patients, the gastrointestinal tract(stomach in four, colon in one, both stomach and colon in one) was concomitantly involved with focal wall thickening. Branching patterns of hypoattenuating lesions were noted in the liver of three patients; two of these had hepatic fascioliasis and one had paragonimiasis. Ectopic parasitic infestation in the peritoneal cavity manifests as mass formation, adjacent gastrointestinal wall thickening, and focal peritonitis. An understanding of these image features is important for both early diagnosis and adequate treatment.

  8. Intraperitoneal ectopic infestation of parasites invading through gastrointestinal tract : CT findings

    International Nuclear Information System (INIS)

    Kim, Jeong Kon; Rha, Sung Eun; Ha, Hyun Kwon; Kim, Pyo Nyun; Lee, Moon Gyu; Auh, Yong Ho; Choi, Byung Ihn; Shim, Jae Chul; Kim, Hyun; Lee, Jong Hwa; Ham, Soo Youn

    1999-01-01

    The purpose of this study was to evaluate the CT findings of parasitic ectopic infestation in the peritoneal cavity, a transitional route for parasites invading the gastrointestinal tract, to migrate to various target organs. CT scans of nine patients with pathologically(n=8) or serologically(n=1) proven intraperitoneal involvement of parasitic infestation were retrospectively reviewed. The primary causes of parasitic infestation in nine patients were Paragonimus westermani(n=5), Sparganosis(n=2), and hepatic fascioliasis(n=2). We analyzed the CT findings with regard to the sites and patterns of lesions in the peritoneal cavity and gastrointestinal track, as well as in other solid organs. The clinical features of these patients were also evaluated. The clinical symptoms and signs were chronic abdominal pain and general weakness in seven patients, while peripheral blood eosinophilia was observed in four. The CT features of these nine patients included multiseptated cystic masses of 2-6cm, diameter (mean 4.1±1.7cm) in the omentum or mesentery in six(67%), omental or mesenteric infiltration in seven(78%), focal peritoneal thickening in seven(78%), 1ymphadenopathy in five(56%), and ascites in four(44%). In six of the nine patients, the gastrointestinal tract(stomach in four, colon in one, both stomach and colon in one) was concomitantly involved with focal wall thickening. Branching patterns of hypoattenuating lesions were noted in the liver of three patients; two of these had hepatic fascioliasis and one had paragonimiasis. Ectopic parasitic infestation in the peritoneal cavity manifests as mass formation, adjacent gastrointestinal wall thickening, and focal peritonitis. An understanding of these image features is important for both early diagnosis and adequate treatment

  9. Role of proline and pyrroline-5-carboxylate metabolism in plant defense against invading pathogens

    Science.gov (United States)

    Qamar, Aarzoo; Mysore, Kirankumar S.; Senthil-Kumar, Muthappa

    2015-01-01

    Pyrroline-5-carboxylate (P5C) is an intermediate product of both proline biosynthesis and catabolism. Recent evidences indicate that proline-P5C metabolism is tightly regulated in plants, especially during pathogen infection and abiotic stress. However, role of P5C and its metabolism in plants has not yet been fully understood. Studies indicate that P5C synthesized in mitochondria has a role in both resistance (R)-gene-mediated and non-host resistance against invading pathogens. Proline dehydrogenase and delta-ornithine amino transferase-encoding genes, both involved in P5C synthesis in mitochondria are implicated in defense response of Nicotiana benthamiana and Arabidopsis thaliana against bacterial pathogens. Such defense response is proposed to involve salicylic acid-dependent pathway, reactive oxygen species (ROS) and hypersensitive response (HR)-associated cell death. Recently HR, a form of programmed cell death (PCD), has been proposed to be induced by changes in mitochondrial P5C synthesis or the increase in P5C levels per se in plants inoculated with either a host pathogen carrying suitable avirulent (Avr) gene or a non-host pathogen. Consistently, A. thaliana mutant plants deficient in P5C catabolism showed HR like cell death when grown in external P5C or proline supplemented medium. Similarly, yeast and plant cells under oxidative stress were shown to increase ROS production and PCD due to increase in P5C levels. Similar mechanism has also been reported as one of the triggers for apoptosis in mammalian cells. This review critically analyzes results from various studies and enumerates the pathways for regulation of P5C levels in the plant cell, especially in mitochondria, during pathogen infection. Further, mechanisms regulating P5C- mediated defense responses, namely HR are outlined. This review also provides new insights into the differential role of proline-P5C metabolism in plants exposed to pathogen infection. PMID:26217357

  10. The ant genomes have been invaded by several types of mariner transposable elements

    Science.gov (United States)

    Lorite, Pedro; Maside, Xulio; Sanllorente, Olivia; Torres, María I.; Periquet, Georges; Palomeque, Teresa

    2012-12-01

    To date, only three types of full-length mariner elements have been described in ants, each one in a different genus of the Myrmicinae subfamily: Sinvmar was isolated from various Solenopsis species, Myrmar from Myrmica ruginodis, and Mboumar from Messor bouvieri. In this study, we report the coexistence of three mariner elements ( Tnigmar- Si, Tnigmar- Mr, and Tnigmar- Mb) in the genome of a single species, Tapinoma nigerrimum (subfamily Dolichoderinae). Molecular evolutionary analyses of the nucleotide sequence data revealed a general agreement between the evolutionary history of most the elements and the ant species that harbour them, and suggest that they are at the vertical inactivation stage of the so-called Mariner Life Cycle. In contrast, significantly reduced levels of synonymous divergence between Mboumar and Tnigmar- Mb and between Myrmar and Botmar (a mariner element isolated from Bombus terrestris), relative to those observed between their hosts, suggest that these elements arrived to the species that host them by horizontal transfer, long after the species' split. The horizontal transfer events for the two pairs of elements could be roughly dated within the last 2 million years and about 14 million years, respectively. As would be expected under this scenario, the coding sequences of the youngest elements, Tnigmar- Mb and Mboumar, are intact and, thus, potentially functional. Each mariner element has a different chromosomal distribution pattern according to their stage within the Mariner Life Cycle. Finally, a new defective transposable element ( Azteca) has also been found inserted into the Tnigmar- Mr sequences showing that the ant genomes have been invaded by at least four different types of mariner elements.

  11. Mapping areas invaded by Prosopis juliflora in Somaliland on Landsat 8 imagery

    Science.gov (United States)

    Rembold, Felix; Leonardi, Ugo; Ng, Wai-Tim; Gadain, Hussein; Meroni, Michele; Atzberger, Clement

    2015-10-01

    Prosopis juliflora is a fast growing tree species originating from South and Central America with a high invasion potential in semi-arid areas around the globe. It was introduced to East Africa for the stabilization of dune systems and for providing fuel wood after prolonged droughts and deforestation in the 1970s and 1980s. In many dry lands in East Africa the species has expanded rapidly and has become challenging to control. The species generally starts its colonization on deep soils with high water availability while in later stages or on poorer soils, its thorny thickets expand into drier grasslands and rangelands. Abandoned or low input farmland is also highly susceptible for invasion as P. juliflora has competitive advantages to native species and is extremely drought tolerant. In this work we describe a rapid approach to detect and map P. juliflora invasion at country level for the whole of Somaliland. Field observations were used to delineate training sites for a supervised classification of Landsat 8 imagery collected during the driest period of the year (i.e., from late February to early April). The choice of such a period allowed to maximise the spectral differences between P. juliflora and other species present in the area, as P. juliflora tends to maintain a higher vigour and canopy water content than native vegetation, when exposed to water stress. The results of our classification map the current status of invasion of Prosopis in Somaliland showing where the plant is invading natural vegetation or agricultural areas. These results have been verified for two spatial subsets of the whole study area with very high resolution (VHR) imagery, proving that Landsat 8 imagery is highly adequate to map P. juliflora. The produced map represents a baseline for understanding spatial distribution of P. juliflora across Somaliland but also for change detection and monitoring of long term dynamics in support to P. juliflora management and control activities.

  12. Chemoradiotherapy for muscle invading bladder carcinoma. final report of a single institutional organ-sparing program

    International Nuclear Information System (INIS)

    Arias, Fernando; Dominguez, Miguel A.; Martinez, Enrique; Illarramendi, Jose J.; Miquelez, Santiago; Pascual, Ignacio; Marcos, Marta

    2000-01-01

    Purpose: Chemoradiotherapy is becoming an alternative to radical cystectomy among patients with muscle invading bladder cancer. We began a prospective study in 1988 to determine the possibilities of conservative treatment and aiming to improve the results obtained by cystectomy alone in invasive bladder cancer. A combination of methotrexate, vinblastine, adriamycin, and cisplatin (M-VAC), followed by radiotherapy and concomitant cisplatin was used. Methods: Fifty patients with good performance status and with stages T2 to T4 operable untreated invasive bladder cancer were entered in the study. Treatment protocol was as follows: (i) cytoreductive transurethral resection; (ii) two cycles of M-VAC chemotherapy; (iii) radiotherapy, 45 Gy on pelvic volume and, at the same time, 20 mg/m 2 cisplatin on days 1 to 5. Cystoscopic evaluation: if there was a complete response, radiotherapy was completed up to 65 Gy; if there was not a complete response, a cystectomy was performed. Median follow-up of the series was 73 months (18-180 m). Results: Tumor response was as follows: 34 complete responses (68%), 9 partial responses (18%), and 7 nonresponses (14%) were observed. The 5-year overall survival and local control were 48% and 47%, respectively. For the complete responder patient, 5-year survival and local control were 65% and 70%, respectively. Severe toxicity was uncommon. The most frequent were leucopenia and cystitis. No treatment-related deaths occurred with either treatment protocol. Conclusions: Conservative combination treatment may be an acceptable alternative to immediate cystectomy in selected patients with bladder cancer, although a randomized clinical trial would be required to produce definitive results

  13. Elucidating mechanical transition effects of invading cancer cells with a subnucleus-scaled microfluidic serial dimensional modulation device†

    OpenAIRE

    Mak, Michael; Reinhart-King, Cynthia A.; Erickson, David

    2013-01-01

    Mechanical boundaries that define and regulate biological processes, such as cell-cell junctions and dense extracellular matrix networks, exist throughout the physiological landscape. During metastasis, cancer cells are able to invade across these barriers and spread to distant tissues. While transgressing boundaries is a necessary step for distal colonies to form, little is known about interface effects on cell behavior during invasion. Here we introduce a device and metric to assess cell tr...

  14. Invading of intrauterine contraceptive device into the sigmoid colon through uterine perforation caused by a blunt trauma.

    Science.gov (United States)

    Davoodabadi, Abdoulhossein; Mohammadzadeh, Mahdi; Amirbeigi, Mahdieh; Jazayeri, Hoda

    2015-01-01

    Intrauterine contraceptive device (IUCD) is relatively safe but still with some serious risks. Uterus perforation is rare and would be fatal. A case of Cu-7 IUCD invading into the sigmoid colon through uterine perforation caused by a pelvic blunt trauma was presented. Our case showed that uterus perforation by an IUCD could induce utero-sigmoid fistula which is likely to be missed. Imaging is required when the patients with IUCD present abdominal pain, particularly with a history of trauma.

  15. Responses to invasion and invader removal differ between native and exotic plant groups in a coastal dune.

    Science.gov (United States)

    Magnoli, Susan M; Kleinhesselink, Andrew R; Cushman, J Hall

    2013-12-01

    The spread of exotic, invasive species is a global phenomenon that is recognized as a major source of environmental change. Although many studies have addressed the effects of exotic plants on the communities they invade, few have quantified the effects of invader removal on plant communities, or considered the degree to which different plant groups vary in response to invasion and invader removal. We evaluated the effects of an exotic succulent, iceplant (Carpobrotus edulis), on a coastal dune plant community in northern California, as well as the community responses to its removal. To assess possible mechanisms by which iceplant affects other plants, we also evaluated its above- and belowground influences on the germination and growth of a dominant exotic annual grass, Bromus diandrus. We found that iceplant invasion was associated with reduced native plant cover as well as increased cover and density of some exotic plants-especially exotic annual grasses. However, iceplant removal did not necessarily lead to a reversal of these effects: removal increased the cover and density of both native and exotic species. We also found that B. diandrus grown in iceplant patches, or in soil where iceplant had been removed, had poorer germination and growth than B. diandrus grown in soil not influenced by iceplant. This suggests that the influence of iceplant on this dune plant community occurs, at least in part, due to belowground effects, and that these effects remain after iceplant has been removed. Our study demonstrates the importance of considering how exotic invasive plants affect not only native species, but also co-occurring exotic taxa. It also shows that combining observational studies with removal experiments can lead to important insights into the influence of invaders and the mechanisms of their effects.

  16. Candida albicans: The Ability to Invade Epithelial Cells and Survive under Oxidative Stress Is Unlinked to Hyphal Length

    Directory of Open Access Journals (Sweden)

    Paloma K. Maza

    2017-07-01

    Full Text Available In its hyphal form, Candida albicans invades epithelial and endothelial cells by two distinct mechanisms: active penetration and induced endocytosis. The latter is dependent on a reorganization of the host cytoskeleton (actin/cortactin recruitment, whilst active penetration does not rely on the host's cellular machinery. The first obstacle for the fungus to reach deep tissues is the epithelial barrier and this interaction is crucial for commensal growth, fungal pathogenicity and host defense. This study aimed to characterize in vitro epithelial HeLa cell invasion by four different isolates of C. albicans with distinct clinical backgrounds, including a C. albicans SC5314 reference strain. All isolates invaded HeLa cells, recruited actin and cortactin, and induced the phosphorylation of both Src-family kinases (SFK and cortactin. Curiously, L3881 isolated from blood culture of a patient exhibited the highest resistance to oxidative stress, although this isolate showed reduced hyphal length and displayed the lowest cell damage and invasion rates. Collectively, these data suggest that the ability of C. albicans to invade HeLa cells, and to reach and adapt to the host's blood, including resistance to oxidative stress, may be independent of hyphal length.

  17. Listeria monocytogenes efficiently invades Caco-2 cells after low-temperature storage in broth and on deli meat.

    Science.gov (United States)

    Larsen, Marianne Halberg; Koch, Anette Granly; Ingmer, Hanne

    2010-09-01

    The objective of this study was to investigate how various growth conditions influence the virulence of Listeria monocytogenes monitored by its ability to invade the epithelial cell lines Caco-2 and INT-407. The growth conditions examined were modified atmosphere-packaged deli meat and brain heart infusion broth (BHI) with and without salt. Five strains of L. monocytogenes were selected to investigate their invasiveness and all strains invaded Caco-2 cells at higher levels than INT-407 cells. Further, the clinical strains (3443 and 3734) were more invasive (p 0.05) in invasiveness after 7 days at 10 degrees C in BHI broth or on sausage, whereas a slight increase (p < 0.05) was observed after incubation on ham for 2 and 4 weeks compared to that in BHI broth. Most importantly, our results show that L. monocytogenes efficiently invade Caco-2 cells even after 4 weeks of storage at chilled temperature. This is highly relevant for safety assessment of this organism in food as these conditions reflect storage of ready-to-eat food products in domestic refrigerators.

  18. Placenta Percreta Invading Broad Ligament and Parametrium in a Woman with Two Previous Cesarean Sections: A Case Report

    Directory of Open Access Journals (Sweden)

    Mansoureh Vahdat

    2012-01-01

    Full Text Available Introduction. The incidence of placenta accreta has dramatically increased due to increasing caesarean section rate all over the world. Placenta percreta is the most severe form of placenta accretes. It frequently results in maternal morbidity and mortality mainly caused by massive obstetric hemorrhage or emergency hysterectomy. Percreta invading into the broad ligament has rarely been previously reported. Case presenting. We presented a case of placenta percreta invading left broad ligament and parametrium in a woman with two previous cesarean sections, which led to massive intraoperative hemorrhage during hysterectomy and transient ischemic encephalopathy. Conclusion. In cases of parametrial involvement, it would be more difficult to decide whether to remove placenta or leave it in site. In surgical removal neither local excision of placental bed and uterine repair nor traditional hysterectomy is adequate if parametrium invaded by placenta. We suggest delayed elective hysterectomy in such cases. So, pregnancy-induced pelvic congestion would be decreased, we can gather an expert team of gynecologists, urologists, and vascular surgeons, we could get plenty of blood products, and we may have the chance to administer methotrexate.

  19. Cost-effective treatment of low-risk carcinoma not invading bladder muscle.

    Science.gov (United States)

    Green, David A; Rink, Michael; Cha, Eugene K; Xylinas, Evanguelos; Chughtai, Bilal; Scherr, Douglas S; Shariat, Shahrokh F; Lee, Richard K

    2013-03-01

    Study Type - Therapy (cost effectiveness analysis) Level of Evidence 2a What's known on the subject? and What does the study add? Bladder cancer is one of the costliest malignancies to treat throughout the life of a patient. The most cost-effective management for low-risk non-muscle-invasive bladder cancer is not known. The current study shows that employing cystoscopic office fulguration for low-risk appearing bladder cancer recurrences can materially impact the cost-effectiveness of therapy. In a follow-up protocol where office fulguration is routinely employed for low-risk bladder cancers, peri-operative intravesical chemotherapy may not provide any additional cost-effectiveness benefit. To examine the cost-effectiveness of fulguration vs transurethral resection of bladder tumour (TURBT) with and without perioperative intravesical chemotherapy (PIC) for managing low-risk carcinoma not invading bladder muscle (NMIBC). Low-risk NMIBC carries a low progression rate, lending support to the use of office-based fulguration for small recurrences rather than traditional TURBT. A Markov state transition model was created to simulate treatment of NMIBC with vs without PIC, with recurrence treated by formal TURBT vs treatment with fulguration. Costing data were obtained from the Medicare Resource Based Relative Value Scale. Data regarding the success of PIC were obtained from the peer-reviewed literature, as were corresponding utilities for bladder cancer-related procedures. Sensitivity analyses were performed. At 5-year follow-up, a strategy of fulguration without PIC was the most cost-effective (mean cost-effectiveness = US $654.8/quality-adjusted life year), despite a lower recurrence rate with PIC. Both fulguration strategies dominated each TURBT strategy. Sensitivity analysis showed that fulguration without PIC dominated all other strategies when the recurrence rate after PIC was increased to ≥14.2% per year. Similarly, the cost-effectiveness of TURBT becomes more

  20. Linking removal targets to the ecological effects of invaders: a predictive model and field test.

    Science.gov (United States)

    Green, Stephanie J; Dulvy, Nicholas K; Brooks, Annabelle M L; Akins, John L; Cooper, Andrew B; Miller, Skylar; Côté, Isabelle M

    , means that we could not identify a single rule of thumb for guiding control efforts. However, our model provides a method for setting reef-specific targets for population control using local monitoring data. Our work is the first to demonstrate that for ongoing invasions, suppressing invaders below densities that cause environmental harm can have a similar effect, in terms of protecting the native ecosystem on a local scale, to achieving complete eradication.

  1. Cultivation of zebra mussels (Dreissena polymorpha) within their invaded range to improve water quality in reservoirs.

    Science.gov (United States)

    McLaughlan, C; Aldridge, D C

    2013-09-01

    Algal and cyanobacterial blooms in reservoirs are driven by nutrient enrichment and may present economic and conservation challenges for water managers. Current approaches such as suppression of algal growth with barley straw, ferric dosing or manipulation of fish stocks have not yielded long term successes. A possibility that has sparked growing interest is the encouragement and cultivation of natural filter feeders, such as mussels, which remove suspended matter from the water and reduce nutrient levels through biodeposition and assimilation. This review focusses on the zebra mussel (Dreissena polymorpha) as a tool for enhancement of water quality in reservoirs. Native to the Ponto-Caspian region, this species has invaded many lakes and reservoirs across North America and Western Europe, where it occurs in very high densities. While purposeful introduction of a non-native species into new sites is socially unacceptable, we investigate the possible benefits of encouraging increased abundance of zebra mussels in sites where the species is already established. We estimate that the annual nitrogen and phosphorus input into a large UK reservoir (Grafham Water) could be assimilated into zebra mussel biomass by encouraging settlement onto 3075 m and 1400 m of commercial mussel ropes, respectively. While zebra mussel cultivation has an incredible capacity to push eutrophic systems towards a clear water state, there are many risks associated with encouraging an invasive species, even within sites where it has already established. The zebra mussel is a prominent biofouler of native unionid mussels and raw water pipes, it changes the physical characteristics of the places it inhabits, in sites low in phosphorus it can be responsible for toxic cyanobacterial blooms, it alters nutrient cycling and community structure and it can have negative impacts on amenity value. Increased propagule pressure from elevated numbers of veliger larvae in the water column may increase the risk

  2. Invader Relative Impact Potential: a new metric to understand and predict the ecological impacts of existing, emerging and future invasive alien species

    OpenAIRE

    Dick, JTA; Laverty, C; Lennon, JJ; Barrios-O'Neill, D; Mensink, PJ; Britton, JR; Medoc, V; Boets, P; Alexander, ME; Taylor, NG; Dunn, AM; Hatcher, MJ; Rosewarne, PJ; Crookes, S; MacIsaac, HJ

    2017-01-01

    1. Predictions of the identities and ecological impacts of invasive alien species are critical for risk assessment, but presently we lack universal and standardized metrics that reliably predict the likelihood and degree of impact of such invaders (i.e. measurable changes in populations of affected species). This need is especially pressing for emerging and potential future invaders that have no invasion history. Such a metric would also ideally apply across diverse taxonomic and trophic gro...

  3. Measuring landscape-scale spread and persistence of an invaded submerged plant community from airborne remote sensing.

    Science.gov (United States)

    Santos, Maria J; Khanna, Shruti; Hestir, Erin L; Greenberg, Jonathan A; Ustin, Susan L

    2016-09-01

    Processes of spread and patterns of persistence of invasive species affect species and communities in the new environment. Predicting future rates of spread is of great interest for timely management decisions, but this depends on models that rely on understanding the processes of invasion and historic observations of spread and persistence. Unfortunately, the rates of spread and patterns of persistence are difficult to model or directly observe, especially when multiple rates of spread and diverse persistence patterns may be co-occurring over the geographic distribution of the invaded ecosystem. Remote sensing systematically acquires data over large areas at fine spatial and spectral resolutions over multiple time periods that can be used to quantify spread processes and persistence patterns. We used airborne imaging spectroscopy data acquired once a year for 5 years from 2004 to 2008 to map an invaded submerged aquatic vegetation (SAV) community across 2220 km 2 of waterways in the Sacramento-San Joaquin River Delta, California, USA, and measured its spread rate and its persistence. Submerged aquatic vegetation covered 13-23 km 2 of the waterways (6-11%) every year. Yearly new growth accounted for 40-60% of the SAV area, ~50% of which survived to following year. Spread rates were overall negative and persistence decreased with time. From this dataset, we were able to identify both radial and saltatorial spread of the invaded SAV in the entire extent of the Delta over time. With both decreasing spread rate and persistence, it is possible that over time the invasion of this SAV community could decrease its ecological impact. A landscape-scale approach allows measurements of all invasion fronts and the spatial anisotropies associated with spread processes and persistence patterns, without spatial interpolation, at locations both proximate and distant to the focus of invasion at multiple points in time. © 2016 by the Ecological Society of America.

  4. The use of steady state neutron flux measurement to determine the size of an invaded region following fluid injection

    International Nuclear Information System (INIS)

    Parsons, R.J.

    1983-01-01

    By using a combination of Monte-Carlo and diffusion theory techniques, the behaviour of the thermal neutron flux during fluid injection is studied. It is shown that the change in neutron flux induced by the fluid injection, is equal to the neutron flux due to a certain thermal neutron source distribution. Using this result, a method of estimating the size of an elliptical invaded region is given. This choice of region shape is not a necessity but a convenience and it is possible that the method may be generalised to include higher order shapes. (author)

  5. [A case of recurrent transverse colon cancer invading the pancreas and duodenum successfully treated with biliary and duodenal stenting].

    Science.gov (United States)

    Tonooka, Toru; Yoshioka, Shigeru; Shiobara, Masayuki; Wakatsuki, Kazuo; Kataoka, Masaaki; Arai, Shuka; Miyazawa, Kotaro; Nakada, Shinichiro; Kita, Kazuhiko; Saito, Hirofumi; Nomoto, Hiromasa; Usui, Masatoshi; Yabiki, Masashi; Ota, Yuki; Oeda, Yoshio

    2013-11-01

    We report a case of recurrent transverse colon cancer invading the pancreas and duodenum that was successfully treated with biliary and duodenal stenting. A 46-year-old man underwent ascending colostomy for the treatment of obstructive transverse colon cancer with hepatic metastasis. Chemotherapy achieved a partial response, but the levels of tumor markers later began to rise again. He then underwent right hemicolectomy and partial hepatectomy. Post-operative chemotherapy was administered, but the recurrent tumor caused obstructive jaundice and duodenal obstruction. These were successfully treated with biliary and duodenal stenting, and the patient was able to remain at home and maintain his quality of life.

  6. Variations of selected soil properties in the grass fields invaded and uninvaded by invasive goldenrod (Solidago canadensis L.

    Directory of Open Access Journals (Sweden)

    Baranová Beáta

    2017-06-01

    Full Text Available Although the invasion of exotic plants has been recognised as the serious cause of the biodiversity loss and natural habitats degradation and threat to the ecosystems functions, just the little attention has been paid to the potential impacts of the goldenrod invasion on the soil properties. Equally, currently obtained results are contrary and ambiguous. We tested whether the grass fields invaded and uninvaded by Canadian goldenrod (Solidago canadensis L. differ in pH, soil moisture, organic carbon (Cox, humus and P, K and Mg contents and related the variations to the chosen environmental variables. We did not find significant distinctions of the studied types of habitats in the selected physico-chemical soil properties as well as the relation between the goldenrod invasion and the changes in soil properties. Nevertheless, whereas the soil reaction, soil moisture and Mg content were higher in the invaded soils, the Cox, humus and P and K contents were higher in the uninvaded ones. Doubtless, further attention need to be paid to this problem.

  7. The fungus that came in from the cold: dry rot's pre-adapted ability to invade buildings.

    Science.gov (United States)

    Balasundaram, S V; Hess, J; Durling, M B; Moody, S C; Thorbek, L; Progida, C; LaButti, K; Aerts, A; Barry, K; Grigoriev, I V; Boddy, L; Högberg, N; Kauserud, H; Eastwood, D C; Skrede, I

    2018-03-01

    Many organisms benefit from being pre-adapted to niches shaped by human activity, and have successfully invaded man-made habitats. One such species is the dry rot fungus Serpula lacrymans, which has a wide distribution in buildings in temperate and boreal regions, where it decomposes coniferous construction wood. Comparative genomic analyses and growth experiments using this species and its wild relatives revealed that S. lacrymans evolved a very effective brown rot decay compared to its wild relatives, enabling an extremely rapid decay in buildings under suitable conditions. Adaptations in intracellular transport machineries promoting hyphal growth, and nutrient and water transport may explain why it is has become a successful invader of timber in houses. Further, we demonstrate that S. lacrymans has poor combative ability in our experimental setup, compared to other brown rot fungi. In sheltered indoor conditions, the dry rot fungus may have limited encounters with other wood decay fungi compared to its wild relatives. Overall, our analyses indicate that the dry rot fungus is an ecological specialist with poor combative ability against other fungi.

  8. Human sepsis-associated Escherichia coli (SEPEC) is able to adhere to and invade kidney epithelial cells in culture

    Energy Technology Data Exchange (ETDEWEB)

    Conceição, R.A. [Departamento de Genética, Evolução e Bioagentes, Universidade Estadual de Campinas, Campinas, SP (Brazil); Ludovico, M.S. [Departamento de Microbiologia, Universidade Estadual de Londrina, Londrina, PR (Brazil); Andrade, C.G.T.J. [Departamento de Biologia Geral, Universidade Estadual de Londrina, Londrina, PR (Brazil); Yano, T. [Departamento de Genética, Evolução e Bioagentes, Universidade Estadual de Campinas, Campinas, SP (Brazil)

    2012-04-13

    The adhesins of extraintestinal pathogenic Escherichia coli are essential for mediating direct interactions between the microbes and the host cell surfaces that they infect. Using fluorescence microscopy and gentamycin protection assays, we observed that 49 sepsis-associated E. coli (SEPEC) strains isolated from human adults adhered to and invaded Vero cells in the presence of D-mannose (100%). In addition, bacteria concentrations of approximately 2 × 10{sup 7} CFU/mL were recovered from Vero cells following an invasion assay. Furthermore, PCR analysis of adhesin genes showed that 98.0% of these SEPEC strains tested positive for fimH, 69.4% for flu, 53.1% for csgA, 38.8% for mat, and 32.7% for iha. Analysis of the invasin genes showed that 16.3% of the SEPEC strains were positive for tia, 12.3% for gimB, and 10.2% for ibeA. Therefore, these data suggest that SEPEC adhesion to cell surfaces occurs through non-fimH mechanisms. Scanning electron microscopy showed the formation of microcolonies on the Vero cell surface. SEPEC invasiveness was also confirmed by the presence of intracellular bacteria, and ultrastructural analysis using electron transmission microscopy revealed bacteria inside the Vero cells. Taken together, these results demonstrate that these SEPEC strains had the ability to adhere to and invade Vero cells. Moreover, these data support the theory that renal cells may be the predominant pathway through which SEPEC enters human blood vessels.

  9. Spatial Pattern and Scale Influence Invader Demographic Response to Simulated Precipitation Change in an Annual Grassland Community.

    Directory of Open Access Journals (Sweden)

    Meghan J Skaer Thomason

    Full Text Available It is important to predict which invasive species will benefit from future changes in climate, and thereby identify those invaders that need particular attention and prioritization of management efforts. Because establishment, persistence, and spread determine invasion success, this prediction requires detailed demographic information. Explicit study of the impact of pattern on demographic response is particularly important for species that are naturally patchy, such as the invasive grass, Aegilops triuncialis. In the northern California Coast Range, where climate change may increase or decrease mean annual rainfall, we conducted a field experiment to understand the interaction of climate change and local-scale patterning on the demography of A. triuncialis. We manipulated precipitation (reduced, ambient, or augmented, seed density, and seeding pattern. Demographic and environmental data were collected for three years following initial seeding. Pattern and scale figure prominently in the demographic response of A. triuncialis to precipitation manipulation. Pattern interacts with precipitation and seeding density in its influence on per-plant seed output. Although per-plot seed production was highest when seeds were not aggregated, per-plant seed output was higher in aggregated patches. Results suggest aggregation of invasive A. triuncialis reduces the detrimental impact of interspecific competition in its invaded community, and that interspecific competition per se has a stronger impact than intraspecific competition.

  10. Co-invading symbiotic mutualists of Medicago polymorpha retain high ancestral diversity and contain diverse accessory genomes.

    Science.gov (United States)

    Porter, Stephanie S; Faber-Hammond, Joshua J; Friesen, Maren L

    2018-01-01

    Exotic, invasive plants and animals can wreak havoc on ecosystems by displacing natives and altering environmental conditions. However, much less is known about the identities or evolutionary dynamics of the symbiotic microbes that accompany invasive species. Most leguminous plants rely upon symbiotic rhizobium bacteria to fix nitrogen and are incapable of colonizing areas devoid of compatible rhizobia. We compare the genomes of symbiotic rhizobia in a portion of the legume's invaded range with those of the rhizobium symbionts from across the legume's native range. We show that in an area of California the legume Medicago polymorpha has invaded, its Ensifer medicae symbionts: (i) exhibit genome-wide patterns of relatedness that together with historical evidence support host-symbiont co-invasion from Europe into California, (ii) exhibit population genomic patterns consistent with the introduction of the majority of deep diversity from the native range, rather than a genetic bottleneck during colonization of California and (iii) harbor a large set of accessory genes uniquely enriched in binding functions, which could play a role in habitat invasion. Examining microbial symbiont genome dynamics during biological invasions is critical for assessing host-symbiont co-invasions whereby microbial symbiont range expansion underlies plant and animal invasions. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Invasion Age and Invader Removal Alter Species Cover and Composition at the Suisun Tidal Marsh, California, USA

    Directory of Open Access Journals (Sweden)

    Sarah Estrella

    2011-05-01

    Full Text Available Wetland ecosystems are vulnerable to plant species invasions, which can greatly alter species composition and ecosystem functioning. The response of these communities to restoration can vary following invader removal, but few studies have evaluated how recent and long-term invasions can affect the plant community’s restoration potential. Perennial pepperweed (Lepidium latifolium has invaded thousands of hectares of marshland in the San Francisco Estuary, California, United States of America, while the effects of invasion and removal of this weed remain poorly studied. In this study, perennial pepperweed was removed along a gradient of invasion age in brackish tidal marshes of Suisun Marsh, within the Estuary. In removal plots, resident plant cover significantly increased during the 2-year study period, particularly in the densest and oldest parts of the perennial pepperweed colonies, while species richness did not change significantly. In bare areas created by removal of perennial pepperweed, recolonization was dominated by three-square bulrush (Schoenoplectus americanus. Ultimately, removal of invasive perennial pepperweed led to reinvasion of the resident plant community within two years. This study illustrates that it is important to consider invasion age, along with exotic species removal, when developing a restoration strategy in wetland ecosystems.

  12. Genetic Studies on CRISPR-Cas Functions in Invader Defense in Sulfolobus islandicus

    DEFF Research Database (Denmark)

    Peng, Wenfang

    Archaea and bacteria contain CRISPR-Cas (clustered regularly interspaced short palindromic repeat-CRISPR-associated) systems that protect themselves against invasion by viruses and plasmids. There are three major types of CRISPR-Cas systems, type I, II and III, that are further divided...... into at least 11 subtypes. I employed Sulfolobus islandicus Rey15A as the model to study CRISPR mechanisms. The model archaeon encodes one subtype I-A (Cascade) and two subtype III-B (Cmr-α and Cmr-β) interference systems with no apparent redundancy in cas genes or in CRISPR systems, which is ideal for genetic...... analysis of cas gene function. Furthermore, a range of genetic tools have been developed for S. islandicus Rey15A in our laboratory and a plasmid interference assay has been successfully developed for testing CRISPR-directed DNA targeting activity, which have provided a solid basis for studying...

  13. Clustered regularly interspaced short palindromic repeats (CRISPRs): the hallmark of an ingenious antiviral defense mechanism in prokaryotes.

    Science.gov (United States)

    Al-Attar, Sinan; Westra, Edze R; van der Oost, John; Brouns, Stan J J

    2011-04-01

    Many prokaryotes contain the recently discovered defense system against mobile genetic elements. This defense system contains a unique type of repetitive DNA stretches, termed Clustered Regularly Interspaced Short Palindromic Repeats (CRISPRs). CRISPRs consist of identical repeated DNA sequences (repeats), interspaced by highly variable sequences referred to as spacers. The spacers originate from either phages or plasmids and comprise the prokaryotes' 'immunological memory'. CRISPR-associated (cas) genes encode conserved proteins that together with CRISPRs make-up the CRISPR/Cas system, responsible for defending the prokaryotic cell against invaders. CRISPR-mediated resistance has been proposed to involve three stages: (i) CRISPR-Adaptation, the invader DNA is encountered by the CRISPR/Cas machinery and an invader-derived short DNA fragment is incorporated in the CRISPR array. (ii) CRISPR-Expression, the CRISPR array is transcribed and the transcript is processed by Cas proteins. (iii) CRISPR-Interference, the invaders' nucleic acid is recognized by complementarity to the crRNA and neutralized. An application of the CRISPR/Cas system is the immunization of industry-relevant prokaryotes (or eukaryotes) against mobile-genetic invasion. In addition, the high variability of the CRISPR spacer content can be exploited for phylogenetic and evolutionary studies. Despite impressive progress during the last couple of years, the elucidation of several fundamental details will be a major challenge in future research.

  14. Costs of living for juvenile Chinook salmon (Oncorhynchus tshawytscha) in an increasingly warming and invaded world

    Science.gov (United States)

    Kuehne, Lauren M.; Olden, Julian D.; Duda, Jeffrey J.

    2012-01-01

    Rapid environmental change in freshwater ecosystems has created a need to understand the interactive effects of multiple stressors, with temperature and invasive predators identified as key threats to imperiled fish species. We tested the separate and interactive effects of water temperature and predation by non-native smallmouth bass (Micropterus dolomieu) on the lethal (mortality) and sublethal (behavior, physiology, and growth) effects for juvenile Chinook salmon (Oncorhynchus tshawytscha) in seminatural stream channel experiments. Over 48 h trials, there was no difference in direct predation with warmer temperatures, but significant interactive effects on sublethal responses of juvenile salmon. Warmer temperatures resulted in significantly stronger and more variable antipredator responses (surface shoaling and swimming activity), while physiological indicators (plasma glucose, plasma cortisol) suggested suppression of physiological mechanisms in response to the combined stressors. These patterns corresponded with additive negative growth in predation, temperature, and combined treatments. Our results suggest that chronic increases in temperature may not increase direct predation over short periods, but can result in significant sublethal costs with negative implications for long-term development, disease resistance, and subsequent size-selective mortality of Pacific salmon.

  15. The importance of the human footprint in shaping the global distribution of terrestrial, freshwater and marine invaders.

    Directory of Open Access Journals (Sweden)

    Belinda Gallardo

    Full Text Available Human activities such as transport, trade and tourism are likely to influence the spatial distribution of non-native species and yet, Species Distribution Models (SDMs that aim to predict the future broad scale distribution of invaders often rely on environmental (e.g. climatic information only. This study investigates if and to what extent do human activities that directly or indirectly influence nature (hereafter the human footprint affect the global distribution of invasive species in terrestrial, freshwater and marine ecosystems. We selected 72 species including terrestrial plants, terrestrial animals, freshwater and marine invasive species of concern in a focus area located in NW Europe (encompassing Great Britain, France, The Netherlands and Belgium. Species Distribution Models were calibrated with the global occurrence of species and a set of high-resolution (9×9 km environmental (e.g. topography, climate, geology layers and human footprint proxies (e.g. the human influence index, population density, road proximity. Our analyses suggest that the global occurrence of a wide range of invaders is primarily limited by climate. Temperature tolerance was the most important factor and explained on average 42% of species distribution. Nevertheless, factors related to the human footprint explained a substantial amount (23% on average of species distributions. When global models were projected into the focus area, spatial predictions integrating the human footprint featured the highest cumulative risk scores close to transport networks (proxy for invasion pathways and in habitats with a high human influence index (proxy for propagule pressure. We conclude that human related information-currently available in the form of easily accessible maps and databases-should be routinely implemented into predictive frameworks to inform upon policies to prevent and manage invasions. Otherwise we might be seriously underestimating the species and areas under

  16. Mercury and persistent organic pollutants in native and invading forage species of the Canadian Arctic: Consequences for food web dynamics.

    Science.gov (United States)

    Pedro, Sara; Fisk, Aaron T; Tomy, Gregg T; Ferguson, Steven H; Hussey, Nigel E; Kessel, Steven T; McKinney, Melissa A

    2017-10-01

    Contaminant dynamics within Arctic marine food webs may be altered through the climate-driven northward invasions of temperate/boreal species. Here, we compare tissue concentrations of total mercury (THg) and legacy and emerging persistent organic pollutants (POPs) in native versus invading forage species sampled from 2012 to 2014 near Arviat, Clyde River, and Resolute Bay, NU, representing, low, mid- and high eastern Canadian Arctic regions, respectively. Concentrations of THg, legacy Σ-polychlorinated biphenyls (ΣPCB) and Σ-organochlorine (ΣOC) pesticides were detected in all forage species, whereas emerging halogenated flame retardants were detected in only a few individuals. Concentrations of major contaminant groups among regions did not vary for Arctic cod (Boreogadus saida), while for sculpin (Cottoidea) there was no clear latitudinal trend. Thus, considering interspecific variation, native sculpin and northern shrimp (Pandalus borealis) had the highest overall concentrations of THg (0.17 ± 0.02 and 0.21 ± 0.01 μg g -1 wet weight, respectively), ΣPCB (322 ± 35 and 245 ± 25 ng g -1 lipid weight (lw), respectively), and ΣOC (413 ± 38 and 734 ± 64 ng g -1 lw, respectively). Comparing the keystone native species, Arctic cod, to its 'replacement' species, capelin (Mallotus villosus) and sandlance (Ammodytes spp.), THg concentrations were higher in Arctic cod compared to capelin (p compound patterns, in capelin and sandlance relative to Arctic cod seem, therefore, more likely related to a more "temperate"-type contaminant signature in the invaders. Nevertheless, the relatively small (up to two-fold) magnitude of these differences suggested limited effects of these ecological changes on contaminant uptake by Arctic piscivores. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Structural and functional changes of soft-bottom ecosystems in northern fjords invaded by the red king crab (Paralithodes camtschaticus)

    Science.gov (United States)

    Oug, Eivind; Sundet, Jan H.; Cochrane, Sabine K. J.

    2018-04-01

    The red king crab invaded Norwegian coastal waters in the early 1990s after having been introduced from the northern Pacific to the Russian Barents Sea coast. The crab stock increased rapidly in NE northern Norway in the latter half of the 1990s, and since 2002 there has been a commercial fishery in the eastern invaded areas. The crab is an active predator on benthic fauna especially feeding in deep soft-bottom environments. The present study is a follow-up of previous studies (2007-09) to assess the effects of the king crab predation on soft bottom species composition, ecological functioning and sediment quality. Macroinfauna (> 1 mm) was investigated in three fjord areas in the Varanger region with low, moderate and very high crab abundances, respectively. Compared with data from 1994, most benthic species were markedly reduced in abundance, in particular non-moving burrowing and tube-dwelling polychaetes, bivalves and echinoderms. However, a few species appeared to recover from 2007-09 to 2012. Changes in ecological functioning were assessed using 'biological traits analysis (BTA)'. Following the crab invasion there was a relative reduction of suspension and surface deposit feeding species, an increase in mobile and predatory organisms and an increase in those with planktotrophic larval development. From low to high crab abundances functioning changed from tube-building, deep deposit feeding and fairly large size to free-living, shallow burrowing and rather small size. With regard to sediment reworking, downward and upward conveyors were reduced whereas surficial modifiers increased. The changes imply that sediment biomixing and bioirrigation were reduced leading to a degraded sedimentary environment. It is suggested that establishing relationships between ecosystem functioning and crab abundances may form the basis for estimating ecological costs of the crab invasion. Such knowledge is important for managing the crab in the Barents Sea area being both a non

  18. Planting sentinel European trees in eastern Asia as a novel method to identify potential insect pest invaders.

    Science.gov (United States)

    Roques, Alain; Fan, Jian-Ting; Courtial, Béatrice; Zhang, Yan-Zhuo; Yart, Annie; Auger-Rozenberg, Marie-Anne; Denux, Olivier; Kenis, Marc; Baker, Richard; Sun, Jiang-Hua

    2015-01-01

    Quarantine measures to prevent insect invasions tend to focus on well-known pests but a large proportion of the recent invaders were not known to cause significant damage in their native range, or were not even known to science before their introduction. A novel method is proposed to detect new potential pests of woody plants in their region of origin before they are introduced to a new continent. Since Asia is currently considered to be the main supplier of insect invaders to Europe, sentinel trees were planted in China during 2007-2011 as an early warning tool to identify the potential for additional Asian insect species to colonize European trees. Seedlings (1-1.5 m tall) of five broadleaved (Quercus petraea, Q. suber, Q. ilex, Fagus sylvatica, and Carpinus betulus) and two conifer species (Abies alba and Cupressus sempervirens) were planted in blocks of 100 seedlings at two widely separated sites (one in a nursery near Beijing and the other in a forest environment near Fuyang in eastern China), and then regularly surveyed for colonization by insects. A total of 104 insect species, mostly defoliators, were observed on these new hosts, and at least six species were capable of larval development. Although a number of the insects observed were probably incidental feeders, 38 species had more than five colonization events, mostly infesting Q. petraea, and could be considered as being capable of switching to European trees if introduced to Europe. Three years was shown to be an appropriate duration for the experiment, since the rate of colonization then tended to plateau. A majority of the identified species appeared to have switched from agricultural crops and fruit trees rather than from forest trees. Although these results are promising, the method is not appropriate for xylophagous pests and other groups developing on larger trees. Apart from the logistical problems, the identification to species level of the specimens collected was a major difficulty. This

  19. The potential distribution of invading Helicoverpa armigera in North America: is it just a matter of time?

    Directory of Open Access Journals (Sweden)

    Darren J Kriticos

    Full Text Available Helicoverpa armigera has recently invaded South and Central America, and appears to be spreading rapidly. We update a previously developed potential distribution model to highlight the global invasion threat, with emphasis on the risks to the United States. The continued range expansion of H. armigera in Central America is likely to change the invasion threat it poses to North America qualitatively, making natural dispersal from either the Caribbean islands or Mexico feasible. To characterise the threat posed by H. armigera, we collated the value of the major host crops in the United States growing within its modelled potential range, including that area where it could expand its range during favourable seasons. We found that the annual value of crops that would be exposed to H. armigera totalled approximately US$78 billion p.a., with US$843 million p.a. worth growing in climates that are optimal for the pest. Elsewhere, H. armigera has developed broad-spectrum pesticide resistance; meaning that if it invades the United States, protecting these crops from significant production impacts could be challenging. It may be cost-effective to undertake pre-emptive biosecurity activities such as slowing the spread of H. armigera throughout the Americas, improving the system for detecting H. armigera, and methods for rapid identification, especially distinguishing between H. armigera, H. zea and potential H. armigera x H. zea hybrids. Developing biological control programs, especially using inundative techniques with entomopathogens and parasitoids could slow the spread of H. armigera, and reduce selective pressure for pesticide resistance. The rapid spread of H. armigera through South America into Central America suggests that its spread into North America is a matter of time. The likely natural dispersal routes preclude aggressive incursion responses, emphasizing the value of preparatory communication with agricultural producers in areas suitable for

  20. Natural short sleeper

    Science.gov (United States)

    Sleep - natural short sleeper ... 7 to 9 hours of sleep each night. Short sleepers sleep less than 75% of what is normal for their age. Natural short sleepers are different from people who chronically do ...

  1. Plant litter effects on soil nutrient availability and vegetation dynamics: changes that occur when annual grasses invade shrub-steppe communities

    Science.gov (United States)

    Sheel Bansal; Roger L. Sheley; Bob Blank; Edward A. Vasquez

    2014-01-01

    Changes in the quantity and quality of plant litter occur in many ecosystems as they are invaded by exotic species, which impact soil nutrient cycling and plant community composition. Such changes in sagebrush-steppe communities are occurring with invasion of annual grasses (AG) into a perennial grass (PG) dominated system. We conducted a 5-year litter manipulation...

  2. Powerful qPCR assays for the early detection of latent invaders: interdisciplinary approaches in clinical cancer research and plant pathology.

    Science.gov (United States)

    Luchi, Nicola; Capretti, Paolo; Pazzagli, Mario; Pinzani, Pamela

    2016-06-01

    Latent invaders represent the first step of disease before symptoms occur in the host. Based on recent findings, tumors are considered to be ecosystems in which cancer cells act as invasive species that interact with the native host cell species. Analogously, in plants latent fungal pathogens coevolve within symptomless host tissues. For these reasons, similar detection approaches can be used for an early diagnosis of the invasion process in both plants and humans to prevent or reduce the spread of the disease. Molecular tools based on the evaluation of nucleic acids have been developed for the specific, rapid, and early detection of human diseases. During the last decades, these techniques to assess and quantify the proliferation of latent invaders in host cells have been transferred from the medical field to different areas of scientific research, such as plant pathology. An improvement in molecular biology protocols (especially referring to qPCR assays) specifically designed and optimized for detection in host plants is therefore advisable. This work is a cross-disciplinary review discussing the use of a methodological approach that is employed within both medical and plant sciences. It provides an overview of the principal qPCR tools for the detection of latent invaders, focusing on comparisons between clinical cancer research and plant pathology, and recent advances in the early detection of latent invaders to improve prevention and control strategies.

  3. The effects of insect biological control on a Tamarix invaded ecosystem: ecosystem water and carbon fluxes and plant-level responses

    Science.gov (United States)

    Background / Questions / Methods: Tamarix spp. (saltcedar) has invaded many river systems in the western United States with detrimental impacts to flora and fauna. Traditional methods of invasive plant control have been ineffective or costly. Therefore, insect biological control of Tamarix with Di...

  4. Planting sentinel European trees in eastern Asia as a novel method to identify potential insect pest invaders.

    Directory of Open Access Journals (Sweden)

    Alain Roques

    Full Text Available Quarantine measures to prevent insect invasions tend to focus on well-known pests but a large proportion of the recent invaders were not known to cause significant damage in their native range, or were not even known to science before their introduction. A novel method is proposed to detect new potential pests of woody plants in their region of origin before they are introduced to a new continent. Since Asia is currently considered to be the main supplier of insect invaders to Europe, sentinel trees were planted in China during 2007-2011 as an early warning tool to identify the potential for additional Asian insect species to colonize European trees. Seedlings (1-1.5 m tall of five broadleaved (Quercus petraea, Q. suber, Q. ilex, Fagus sylvatica, and Carpinus betulus and two conifer species (Abies alba and Cupressus sempervirens were planted in blocks of 100 seedlings at two widely separated sites (one in a nursery near Beijing and the other in a forest environment near Fuyang in eastern China, and then regularly surveyed for colonization by insects. A total of 104 insect species, mostly defoliators, were observed on these new hosts, and at least six species were capable of larval development. Although a number of the insects observed were probably incidental feeders, 38 species had more than five colonization events, mostly infesting Q. petraea, and could be considered as being capable of switching to European trees if introduced to Europe. Three years was shown to be an appropriate duration for the experiment, since the rate of colonization then tended to plateau. A majority of the identified species appeared to have switched from agricultural crops and fruit trees rather than from forest trees. Although these results are promising, the method is not appropriate for xylophagous pests and other groups developing on larger trees. Apart from the logistical problems, the identification to species level of the specimens collected was a major

  5. The Arf GTPase-activating protein family is exploited by Salmonella enterica serovar Typhimurium to invade nonphagocytic host cells.

    Science.gov (United States)

    Davidson, Anthony C; Humphreys, Daniel; Brooks, Andrew B E; Hume, Peter J; Koronakis, Vassilis

    2015-02-10

    To establish intracellular infections, Salmonella bacteria trigger host cell membrane ruffling and invasion by subverting cellular Arf guanine nucleotide exchange factors (GEFs) that activate Arf1 and Arf6 GTPases by promoting GTP binding. A family of cellular Arf GTPase-activating proteins (GAPs) can downregulate Arf signaling by stimulating GTP hydrolysis, but whether they do this during infection is unknown. Here, we uncovered a remarkable role for distinct Arf GAP family members in Salmonella invasion. The Arf6 GAPs ACAP1 and ADAP1 and the Arf1 GAP ASAP1 localized at Salmonella-induced ruffles, which was not the case for the plasma membrane-localized Arf6 GAPs ARAP3 and GIT1 or the Golgi-associated Arf1 GAP1. Surprisingly, we found that loss of ACAP1, ADAP1, or ASAP1 impaired Salmonella invasion, revealing that GAPs cannot be considered mere terminators of cytoskeleton remodeling. Salmonella invasion was restored in Arf GAP-depleted cells by expressing fast-cycling Arf derivatives, demonstrating that Arf GTP/GDP cycles facilitate Salmonella invasion. Consistent with this view, both constitutively active and dominant-negative Arf derivatives that cannot undergo GTP/GDP cycles inhibited invasion. Furthermore, we demonstrated that Arf GEFs and GAPs colocalize at invading Salmonella and collaborate to drive Arf1-dependent pathogen invasion. This study revealed that Salmonella bacteria exploit a remarkable interplay between Arf GEFs and GAPs to direct cycles of Arf GTPase activation and inactivation. These cycles drive Salmonella cytoskeleton remodeling and enable intracellular infections. To initiate infections, the Salmonella bacterial pathogen remodels the mammalian actin cytoskeleton and invades host cells by subverting host Arf GEFs that activate Arf1 and Arf6 GTPases. Cellular Arf GAPs deactivate Arf GTPases and negatively regulate cell processes, but whether they target Arfs during infection is unknown. Here, we uncovered an important role for the Arf GAP

  6. Linking niche theory to ecological impacts of successful invaders: insights from resource fluctuation-specialist herbivore interactions.

    Science.gov (United States)

    Gidoin, Cindy; Roques, Lionel; Boivin, Thomas

    2015-03-01

    Theories of species coexistence and invasion ecology are fundamentally connected and provide a common theoretical framework for studying the mechanisms underlying successful invasions and their ecological impacts. Temporal fluctuations in resource availability and differences in life-history traits between invasive and resident species are considered as likely drivers of the dynamics of invaded communities. Current critical issues in invasion ecology thus relate to the extent to which such mechanisms influence coexistence between invasive and resident species and to the ability of resident species to persist in an invasive-dominated ecosystem. We tested how a fluctuating resource, and species trait differences may explain and help predict long-term impacts of biological invasions in forest specialist insect communities. We used a simple invasion system comprising closely related invasive and resident seed-specialized wasps (Hymenoptera: Torymidae) competing for a well-known fluctuating resource and displaying divergent diapause, reproductive and phenological traits. Based on extensive long-term field observations (1977-2010), we developed a combination of mechanistic and statistical models aiming to (i) obtain a realistic description of the population dynamics of these interacting species over time, and (ii) clarify the respective contributions of fluctuation-dependent and fluctuation-independent mechanisms to long-term impact of invasion on the population dynamics of the resident wasp species. We showed that a fluctuation-dependent mechanism was unable to promote coexistence of the resident and invasive species. Earlier phenology of the invasive species was the main driver of invasion success, enabling the invader to exploit an empty niche. Phenology also had the greatest power to explain the long-term negative impact of the invasive on the resident species, through resource pre-emption. This study provides strong support for the critical role of species

  7. Bladder cancer: The combination of chemotherapy and irradiation in the treatment of patients with muscle-invading tumors

    International Nuclear Information System (INIS)

    Shipley, William U.; Zietman, Anthony L.

    1996-01-01

    In the USA the recommended treatment for patients with muscle-invading transitional cell cancer of the bladder is usually radical cystectomy. Conservative surgery irradiation, and cisplatin-based systemic chemotherapy are, however, each effective for some patients. Although they provide the opportunity for bladder preservation, each modality, when used alone, is inferior to radical cystectomy in terms of local control and, perhaps, survival. Many recent publications have now documented the efficacy of combined modality treatment protocols employing all three of these modalities together. All employ a selective approach in which the patients only receive full-dose radiation if they have had a complete response to induction CMT. Overall survival data for T2-T3a patients are certainly as good as any reported cystectomy series of similarly clinically staged and similar aged patients. Radiation adds very significantly to the transurethral resection and systemic chemotherapy to maintain the bladder free of tumor. Substantially higher rates of pathologic confirmation of complete response are found following transurethral surgery and chemoradiation when compared with transurethral surgery and chemotherapy omitting the radiation. Overall survival is as good as cystectomy based approaches at 48-54% and over 80% of these long-term survivors keep their bladders. Following such therapies, 20-30% will subsequently develop superficial tumors. These patients may still be well treated by standard methods using transurethral resection and intravesical drugs. The concern of urologists that the conserved irradiated bladder functions poorly has also been answered by recent reports using modern radiation techniques. The instance of cystectomy for bladder shrinkage is repeatedly below 2%. Furthermore, sexual function is commonly preserved. The systemic morbidity of the chemotherapy is relatively high, but new approached using anti-emetics and GCSF now allow this to be reduced. In many

  8. Characterization of a newly established aggregation of the invasive ladybeetle Harmonia axyridis and current status of the invader in Spain

    Energy Technology Data Exchange (ETDEWEB)

    Pons, X.; Roca, M.; Lumbierres, B.; Lucas, E.

    2015-07-01

    The multicoloured Asian ladybeetle, Harmonia axyridis (Pallas), an invasive biocontrol agent introduced in North and South America, as well as in Europe for aphid control, drastically affected assemblages of native coccinellid species, local communities and people. Although the insect is common in several European countries and it was released in Spain for aphid control in 1995, no evidence of population establishment has been reported until 2011. In the present paper, 1) we summarize the records of the invasive ladybeetle in Spain and provide numerous new mentions, and 2) we follow for the first time an overwintering aggregation from autumn to spring and characterize some individual features which allow us to determine its phenology of the establishment and spreading. The results establish clearly that: 1) H. axyridis is (until now) restricted to Catalonia (NE Spain) but the invading process is in progress and the insect is able to occupy different habitats; 2) the ladybeetle overwinters successfully in Spain without significant natural mortality or parasitism; 3) the form succinea represents 73-81% of the overwintering individuals, and 4) the invasion takes probably its origin from Southern France. The potential impact of the invasion by H. axyridis in Spain is discussed. (Author)

  9. Secondary Contact and Admixture between Independently Invading Populations of the Western Corn Rootworm, Diabrotica virgifera virgifera in Europe

    Science.gov (United States)

    Bermond, Gérald; Ciosi, Marc; Lombaert, Eric; Blin, Aurélie; Boriani, Marco; Furlan, Lorenzo; Toepfer, Stefan; Guillemaud, Thomas

    2012-01-01

    The western corn rootworm, Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae), is one of the most destructive pests of corn in North America and is currently invading Europe. The two major invasive outbreaks of rootworm in Europe have occurred, in North-West Italy and in Central and South-Eastern Europe. These two outbreaks originated from independent introductions from North America. Secondary contact probably occurred in North Italy between these two outbreaks, in 2008. We used 13 microsatellite markers to conduct a population genetics study, to demonstrate that this geographic contact resulted in a zone of admixture in the Italian region of Veneto. We show that i) genetic variation is greater in the contact zone than in the parental outbreaks; ii) several signs of admixture were detected in some Venetian samples, in a Bayesian analysis of the population structure and in an approximate Bayesian computation analysis of historical scenarios and, finally, iii) allelic frequency clines were observed at microsatellite loci. The contact between the invasive outbreaks in North-West Italy and Central and South-Eastern Europe resulted in a zone of admixture, with particular characteristics. The evolutionary implications of the existence of a zone of admixture in Northern Italy and their possible impact on the invasion success of the western corn rootworm are discussed. PMID:23189184

  10. Geographic structuring and transgenerational maternal effects shape germination in native, but not introduced, populations of a widespread plant invader.

    Science.gov (United States)

    Alba, Christina; Moravcová, Lenka; Pyšek, Petr

    2016-05-01

    Germination is critical in determining species distributions and invasion dynamics. However, is it unclear how often invasive populations evolve germination characteristics different from native populations, because few studies have isolated genetic variation by using seed from garden-grown plants. Additionally, while herbivore-induced transgenerational effects are common, it is unknown whether maternal herbivory differentially shapes germination in native and introduced offspring. We explored germination in native and introduced populations of the North American invader Verbascum thapsus using seed from garden-grown maternal plants, half of which were protected from herbivores. To elucidate (1) germination niche breadth and (2) whether germination conditions affected expression of genetic structuring among populations, we germinated seed under four ecologically relevant temperature regimes. Native populations had a wide germination niche breadth, germinating as well as or better than introduced populations. At cooler temperatures, native populations exhibited a genetically based environmental cline indicative of local adaptation, with populations from warmer locales germinating better than populations from cooler locales. However, this cline was obscured when maternal plants were attacked by herbivores, revealing that local stressors can override the expression of geographic structuring. Introduced populations did not exhibit clinal variation, suggesting its disruption during the introduction process. Native and introduced populations have evolved genetic differences in germination. The result of this difference manifests in a wider germination niche breadth in natives, suggesting that the invasive behavior of V. thapsus in North America is attributable to other factors. © 2016 Botanical Society of America.

  11. Fusarium spp. is able to grow and invade healthy human nails as a single source of nutrients.

    Science.gov (United States)

    Galletti, J; Negri, M; Grassi, F L; Kioshima-Cotica, É S; Svidzinski, T I E

    2015-09-01

    Onychomycosis caused by Fusarium spp. is emerging, but some factors associated with its development remain unclear, such as whether this genus is keratinolytic. The main aim of the present study was to evaluate the ability of Fusarium to use the human nail as a single source of nutrients. We also performed an epidemiological study and antifungal susceptibility testing of Fusarium spp. that were isolated from patients with onychomycosis. The epidemiological study showed that Fusarium species accounted for 12.4 % of onychomycosis cases, and it was the most common among nondermatophyte molds. The most frequent species identified were F. oxysporum (36.5 %), F. solani (31.8 %), and F. subglutinans (8.3 %). Fluconazole was not active against Fusarium spp., and the response to terbinafine varied according to species. Fusarium was able to grow in vitro without the addition of nutrients and invade healthy nails. Thus, we found that Fusarium uses keratin as a single source of nutrients, and the model proposed herein may be useful for future studies on the pathogenesis of onychomycosis.

  12. Potential Asteraceae Invaders in Taiwan: Insights from the Flora and Herbarium Records of Casual and Naturalized Alien Species

    Directory of Open Access Journals (Sweden)

    Shan-Huah Wu

    2005-03-01

    Full Text Available Naturalization has been shown to be one of the primary stages of plant invasions; therefore, studies on naturalized plant species may generate valuable insights of possible invaders and invasions. Background information of casual and naturalized Asteraceae species provided by a comprehensive list of casual and naturalized species in Taiwan was examined to estimate the basic biological traits and geological origins of potential invasive species in this study. Besides, herbarium records were collected and analyzed to predict the invasiveness of casual and naturalized Asteraceae species. Our results showed that 44.0% out of the 51 casual and naturalized Asteraceae species were classified as invasive in the field, and a notable portion of these species were probably introduced accidently. Tropical Americas were the most important origins of casual and naturalized Asteraceae species, followed by Europe and temperate Americas. Most of the casual and naturalized Asteraceae species were annual herbs, and a few perennial species categorized as invasive may cause profound environmental problems. The herbarium record showed that species possessed different numbers of localities within the same time frame. We suggested that casual and naturalized Asteraceae species collected in more localities are more invasive than those species found in fewer localities within the same period of time.

  13. Detection of virulence genes determining the ability to adhere and invade in Campylobacter spp. from cattle and swine in Poland.

    Science.gov (United States)

    Wysok, Beata; Wojtacka, Joanna

    2018-02-01

    The aim of the study was to determine the prevalence of virulence genes responsible for the adhesion (flaA, cadF and racR) and invasion (virB11, iam and pldA) in Campylobacter isolates from cattle and swine and determine their adherence and invasion abilities. The studies conducted revealed high prevalence rate of adherence and invasion associated genes irrespective of the isolates origin. All Campylobacter strains of swine and cattle origin adhered to HeLa cells at mean level 0.1099% ± SD 0.1341% and 0.0845% ± SD 0.1304% of starting viable inoculum, respectively. However swine isolates exhibited higher invasion abilities (0.0012% ± SD 0.0011%) compared to bovine isolates (0.00038% ± SD 0.00055%). The results obtained revealed significantly positive correlation between invasion and adherence abilities of swine origin isolates (R = 0.4867 in regard to C. jejuni and R = 0.4507 in regard to C. coli) and bovine origin isolates (R = 0.726 in regard to C. jejuni). Bacterial virulence is multifactorial and it is affected by the expression of virulence genes. Moreover the presence of virulence genes determines the ability of Campylobacter isolates to adhere and invade the cells. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Host persistence or extinction from emerging infectious disease: insights from white-nose syndrome in endemic and invading regions.

    Science.gov (United States)

    Hoyt, Joseph R; Langwig, Kate E; Sun, Keping; Lu, Guanjun; Parise, Katy L; Jiang, Tinglei; Frick, Winifred F; Foster, Jeffrey T; Feng, Jiang; Kilpatrick, A Marm

    2016-03-16

    Predicting species' fates following the introduction of a novel pathogen is a significant and growing problem in conservation. Comparing disease dynamics between introduced and endemic regions can offer insight into which naive hosts will persist or go extinct, with disease acting as a filter on host communities. We examined four hypothesized mechanisms for host-pathogen persistence by comparing host infection patterns and environmental reservoirs for Pseudogymnoascus destructans (the causative agent of white-nose syndrome) in Asia, an endemic region, and North America, where the pathogen has recently invaded. Although colony sizes of bats and hibernacula temperatures were very similar, both infection prevalence and fungal loads were much lower on bats and in the environment in Asia than North America. These results indicate that transmission intensity and pathogen growth are lower in Asia, likely due to higher host resistance to pathogen growth in this endemic region, and not due to host tolerance, lower transmission due to smaller populations, or lower environmentally driven pathogen growth rate. Disease filtering also appears to be favouring initially resistant species in North America. More broadly, determining the mechanisms allowing species persistence in endemic regions can help identify species at greater risk of extinction in introduced regions, and determine the consequences for disease dynamics and host-pathogen coevolution. © 2016 The Author(s).

  15. [A Case Report on Successful Larynx-Preserving Surgery for a Cervical Esophageal Cancer That Invaded the Hypopharynx].

    Science.gov (United States)

    Shiraishi, Osamu; Kato, Hiroaki; Iwama, Mitsuru; Hiraki, Yoko; Yasuda, Atsushi; Shinkai, Masayuki; Imano, Motohiro; Kimura, Yutaka; Imamoto, Haruhiko; Yasuda, Takushi

    2017-11-01

    The patient was a 58-year-old man suffering from dysphagia. He was diagnosed with T3 cervicalesophagealcancer that invaded the posterior hypopharyngealwal lwith lymph node metastasis. The patient received neoadjuvant chemoradiotherapy (30 Gy with CDDP/5-FU), followed by larynx-preserving surgery(LPS)for cervicalesophagealcancer. Two techniques for successfulLPS consist of the dissections of cricopharyngealmuscl e and the inferior pharyngealsphincter, and the complete division of the bilateral infrahyoid muscles attached to the sternum(CDBIMS). The former technique of releasing the esophagus from the trachea at the cricoid cartilage level results in the extension of the oral surgical margin. The latter technique is expected to prevent postoperative aspiration pneumonia, as the lack of flexibility of scarred infrahyoid muscles is regarded as one of the major causes of dysfunction in swallowing. Free jejunum was transferred for cervical reconstruction. Pathological examination indicated degenerated squamous cell carcinoma(ypT2, INF b, ly0, v0, PM0, ypN0, ypStage II A). Although the patient had recurrent nerve palsy, he could eat meals without aspiration. He returned to normal life after discharge from the hospital. Five years after surgery, no recurrence had been observed.

  16. Stable isotopes of nitrogen and carbon in an aquatic food web recently invaded by Dreissena polymorpha (Pallas)

    International Nuclear Information System (INIS)

    Mitchell, M.J.; Mills, E.L.; Idrisi, N.; Michener, R.

    1996-01-01

    The carbon and nitrogen concentrations and the stable isotopic compositions (δ 13 C and δ 15 N) of major abiotic and biotic constituents were determined in Oneida Lake, New York. This lake was invaded by the zebra mussel (Dreissena polymorpha) in 1990 and there have been concomitant changes in various biotic and abiotic lake properties. The C (46-49%) and N (12%) concentrations and C:N ratios (3.9-4) of zebra mussel flesh were similar to those reported for other lakes. Trophic positions were reflected in the δ 15 N values for which walleye > gizzard shad and yellow perch > Daphnia spp. and zebra mussel flesh > seston and sediment. There was an average increase of 3.6% 0 15 N per trophic transfer. Results from the δ 13 C analysis suggest that Daphnia spp. were using a distinct source of organic carbon whereas zebra mussel were using the entire seston resource. Only yellow perch showed a significant shift in δ 13 C values (1.1% 0 ), possibly reflecting a shift in a food source and diet from 1992 to 1993. (author). 48 refs., 2 tabs., 2 figs

  17. Stress tolerance and ecophysiological ability of an invader and a native species in a seasonally dry tropical forest.

    Science.gov (United States)

    Oliveira, Marciel Teixeira; Matzek, Virginia; Dias Medeiros, Camila; Rivas, Rebeca; Falcão, Hiram Marinho; Santos, Mauro Guida

    2014-01-01

    Ecophysiological traits of Prosopis juliflora (Sw.) DC. and a phylogenetically and ecologically similar native species, Anadenanthera colubrina (Vell.) Brenan, were studied to understand the invasive species' success in caatinga, a seasonally dry tropical forest ecosystem of the Brazilian Northeast. To determine if the invader exhibited a superior resource-capture or a resource-conservative strategy, we measured biophysical and biochemical parameters in both species during dry and wet months over the course of two years. The results show that P. juliflora benefits from a flexible strategy in which it frequently outperforms the native species in resource capture traits under favorable conditions (e.g., photosynthesis), while also showing better stress tolerance (e.g., antioxidant activity) and water-use efficiency in unfavorable conditions. In addition, across both seasons the invasive has the advantage over the native with higher chlorophyll/carotenoids and chlorophyll a/b ratios, percent N, and leaf protein. We conclude that Prosopis juliflora utilizes light, water and nutrients more efficiently than Anadenanthera colubrina, and suffers lower intensity oxidative stress in environments with reduced water availability and high light radiation.

  18. Metabolic Profiling of Pyrrolizidine Alkaloids in Foliage of Two Echium spp. Invaders in Australia—A Case of Novel Weapons?

    Directory of Open Access Journals (Sweden)

    Dominik Skoneczny

    2015-11-01

    Full Text Available Metabolic profiling allows for simultaneous and rapid annotation of biochemically similar organismal metabolites. An effective platform for profiling of toxic pyrrolizidine alkaloids (PAs and their N-oxides (PANOs was developed using ultra high pressure liquid chromatography quadrupole time-of-flight (UHPLC-QTOF mass spectrometry. Field-collected populations of invasive Australian weeds, Echium plantagineum and E. vulgare were raised under controlled glasshouse conditions and surveyed for the presence of related PAs and PANOs in leaf tissues at various growth stages. Echium plantagineum possessed numerous related and abundant PANOs (>17 by seven days following seed germination, and these were also observed in rosette and flowering growth stages. In contrast, the less invasive E. vulgare accumulated significantly lower levels of most PANOs under identical glasshouse conditions. Several previously unreported PAs were also found at trace levels. Field-grown populations of both species were also evaluated for PA production and highly toxic echimidine N-oxide was amongst the most abundant PANOs in foliage of both species. PAs in field and glasshouse plants were more abundant in the more widely invasive species, E. plantagineum, and may provide competitive advantage by increasing the plant’s capacity to deter natural enemies in its invaded range through production of novel weapons.

  19. Metabolic Profiling of Pyrrolizidine Alkaloids in Foliage of Two Echium spp. Invaders in Australia—A Case of Novel Weapons?

    Science.gov (United States)

    Skoneczny, Dominik; Weston, Paul A.; Zhu, Xiaocheng; Gurr, Geoff M.; Callaway, Ragan M.; Weston, Leslie A.

    2015-01-01

    Metabolic profiling allows for simultaneous and rapid annotation of biochemically similar organismal metabolites. An effective platform for profiling of toxic pyrrolizidine alkaloids (PAs) and their N-oxides (PANOs) was developed using ultra high pressure liquid chromatography quadrupole time-of-flight (UHPLC-QTOF) mass spectrometry. Field-collected populations of invasive Australian weeds, Echium plantagineum and E. vulgare were raised under controlled glasshouse conditions and surveyed for the presence of related PAs and PANOs in leaf tissues at various growth stages. Echium plantagineum possessed numerous related and abundant PANOs (>17) by seven days following seed germination, and these were also observed in rosette and flowering growth stages. In contrast, the less invasive E. vulgare accumulated significantly lower levels of most PANOs under identical glasshouse conditions. Several previously unreported PAs were also found at trace levels. Field-grown populations of both species were also evaluated for PA production and highly toxic echimidine N-oxide was amongst the most abundant PANOs in foliage of both species. PAs in field and glasshouse plants were more abundant in the more widely invasive species, E. plantagineum, and may provide competitive advantage by increasing the plant’s capacity to deter natural enemies in its invaded range through production of novel weapons. PMID:26561809

  20. Metabolic Profiling of Pyrrolizidine Alkaloids in Foliage of Two Echium spp. Invaders in Australia--A Case of Novel Weapons?

    Science.gov (United States)

    Skoneczny, Dominik; Weston, Paul A; Zhu, Xiaocheng; Gurr, Geoff M; Callaway, Ragan M; Weston, Leslie A

    2015-11-06

    Metabolic profiling allows for simultaneous and rapid annotation of biochemically similar organismal metabolites. An effective platform for profiling of toxic pyrrolizidine alkaloids (PAs) and their N-oxides (PANOs) was developed using ultra high pressure liquid chromatography quadrupole time-of-flight (UHPLC-QTOF) mass spectrometry. Field-collected populations of invasive Australian weeds, Echium plantagineum and E. vulgare were raised under controlled glasshouse conditions and surveyed for the presence of related PAs and PANOs in leaf tissues at various growth stages. Echium plantagineum possessed numerous related and abundant PANOs (>17) by seven days following seed germination, and these were also observed in rosette and flowering growth stages. In contrast, the less invasive E. vulgare accumulated significantly lower levels of most PANOs under identical glasshouse conditions. Several previously unreported PAs were also found at trace levels. Field-grown populations of both species were also evaluated for PA production and highly toxic echimidine N-oxide was amongst the most abundant PANOs in foliage of both species. PAs in field and glasshouse plants were more abundant in the more widely invasive species, E. plantagineum, and may provide competitive advantage by increasing the plant's capacity to deter natural enemies in its invaded range through production of novel weapons.

  1. Shortness of Breath

    Science.gov (United States)

    ... filled with air (called pneumotho- rax), it will hinder expansion of the lung, resulting in shortness of ... of Chest Physi- cians. Shortness of Breath: Patient Education. http: / / www. onebreath. org/ document. doc? id= 113. ...

  2. Short-circuit logic

    NARCIS (Netherlands)

    Bergstra, J.A.; Ponse, A.

    2010-01-01

    Short-circuit evaluation denotes the semantics of propositional connectives in which the second argument is only evaluated if the first argument does not suffice to determine the value of the expression. In programming, short-circuit evaluation is widely used. A short-circuit logic is a variant of

  3. Ombud's corner: space invaders

    CERN Multimedia

    Sudeshna Datta-Cockerill

    2015-01-01

    When normal communication breaks down and there is no sharing anymore, office-mates can become ‘space invaders’. Very often, the situation can be resolved effectively by taking just a few simple steps...   The lack of office space at CERN is a permanent issue that the various departments regularly have to address. As a result, very often this precious space where we spend the entire day has to be shared with other colleagues. Office-mates may come from different backgrounds and cultures and may have very different habits and behaviours; they may also have different activities during the day, sometimes requiring unusual, (perhaps even strange?) interactions with the space they occupy; finally, their presence might be irregular, making it very difficult for us to establish a stable relationship. Mark and Claire share an office as well as some professional activities. In the beginning, the relationship seems to work normally but, over time, the communication between them ste...

  4. Verdi Invades the Kindergarten.

    Science.gov (United States)

    McGirr, Paula Ifft

    1995-01-01

    Children can complement all areas of their language learning with music, and can enhance their musical activities with language. Opportunities to experience sounds, language, and rhythmic movement support the learning and development of the whole child. Activities dealing with children's books that have musical themes, song picture books, and…

  5. Increasing Potential Risk of a Global Aquatic Invader in Europe in Contrast to Other Continents under Future Climate Change

    Science.gov (United States)

    Liu, Xuan; Guo, Zhongwei; Ke, Zunwei; Wang, Supen; Li, Yiming

    2011-01-01

    Background Anthropogenically-induced climate change can alter the current climatic habitat of non-native species and can have complex effects on potentially invasive species. Predictions of the potential distributions of invasive species under climate change will provide critical information for future conservation and management strategies. Aquatic ecosystems are particularly vulnerable to invasive species and climate change, but the effect of climate change on invasive species distributions has been rather neglected, especially for notorious global invaders. Methodology/Principal Findings We used ecological niche models (ENMs) to assess the risks and opportunities that climate change presents for the red swamp crayfish (Procambarus clarkii), which is a worldwide aquatic invasive species. Linking the factors of climate, topography, habitat and human influence, we developed predictive models incorporating both native and non-native distribution data of the crayfish to identify present areas of potential distribution and project the effects of future climate change based on a consensus-forecast approach combining the CCCMA and HADCM3 climate models under two emission scenarios (A2a and B2a) by 2050. The minimum temperature from the coldest month, the human footprint and precipitation of the driest quarter contributed most to the species distribution models. Under both the A2a and B2a scenarios, P. clarkii shifted to higher latitudes in continents of both the northern and southern hemispheres. However, the effect of climate change varied considerately among continents with an expanding potential in Europe and contracting changes in others. Conclusions/Significance Our findings are the first to predict the impact of climate change on the future distribution of a globally invasive aquatic species. We confirmed the complexities of the likely effects of climate change on the potential distribution of globally invasive species, and it is extremely important to develop

  6. Brown trout as an invader: A synthesis of problems and perspectives in western North America: Chapter 20

    Science.gov (United States)

    Budy, Phaedra; Gaeta, Jereme W.; Lobón-Cerviá, Javier; Sanz, Nuria

    2017-01-01

    Brown trout are one of the most pervasive and successful invaders worldwide and are ubiquitous across the Intermountain West, USA (IMW). This species is the foundation of extremely popular and economically significant sport fisheries despite well-established negative effects on native fishes and ecosystems, resulting in very challenging, and often opposing, conservation and management goals. Herein, we review the direct (e.g., competition and predation) and indirect (e.g., disease vectors) pathways through which brown trout across the IMW have posed a threat to native species. We discuss the importance of brown trout as economically and culturally important fisheries, especially in novel tailwater ecosystems created by damming. To this end, we surveyed 24 experts from eight states across the IMW to document the relevance of novel brown trout fisheries in 51 tailwaters and found brown trout are thriving in these novel ecosystems, which are often unsuitable for native fishes. We discuss the challenging interplay between protecting native species and managing novel brown trout fisheries. Notably, the future of exotic brown trout in the IMW is shifting as the prestige of native fisheries is growing and many non-native eradication efforts have occurred. The future of exotic brown trout in the IMW, will depend on the nexus of public sentiment and policy, the effectiveness of eradication efforts, and the effect of climate change on both the native fishes and exotic brown trout. Regardless, because brown trout are pervasive and have a broad distribution through the IMW, populations of this species will likely persist at least in some locations into the future.

  7. Comparative Transcriptomic Exploration Reveals Unique Molecular Adaptations of Neuropathogenic Trichobilharzia to Invade and Parasitize Its Avian Definitive Host.

    Directory of Open Access Journals (Sweden)

    Roman Leontovyč

    2016-02-01

    Full Text Available To date, most molecular investigations of schistosomatids have focused principally on blood flukes (schistosomes of humans. Despite the clinical importance of cercarial dermatitis in humans caused by Trichobilharzia regenti and the serious neuropathologic disease that this parasite causes in its permissive avian hosts and accidental mammalian hosts, almost nothing is known about the molecular aspects of how this fluke invades its hosts, migrates in host tissues and how it interacts with its hosts' immune system. Here, we explored selected aspects using a transcriptomic-bioinformatic approach. To do this, we sequenced, assembled and annotated the transcriptome representing two consecutive life stages (cercariae and schistosomula of T. regenti involved in the first phases of infection of the avian host. We identified key biological and metabolic pathways specific to each of these two developmental stages and also undertook comparative analyses using data available for taxonomically related blood flukes of the genus Schistosoma. Detailed comparative analyses revealed the unique involvement of carbohydrate metabolism, translation and amino acid metabolism, and calcium in T. regenti cercariae during their invasion and in growth and development, as well as the roles of cell adhesion molecules, microaerobic metabolism (citrate cycle and oxidative phosphorylation, peptidases (cathepsins and other histolytic and lysozomal proteins in schistosomula during their particular migration in neural tissues of the avian host. In conclusion, the present transcriptomic exploration provides new and significant insights into the molecular biology of T. regenti, which should underpin future genomic and proteomic investigations of T. regenti and, importantly, provides a useful starting point for a range of comparative studies of schistosomatids and other trematodes.

  8. Knocking on Heaven's Door: Are Novel Invaders Necessarily Facing Naïve Native Species on Islands?

    Directory of Open Access Journals (Sweden)

    Agathe Gérard

    Full Text Available The impact of alien predator species on insular native biota has often been attributed to island prey naïveté (i.e. lack of, or inefficient, anti-predator behavior. Only rarely, however, has the concept of island prey naïveté been tested, and then only a posteriori (i.e. hundreds or thousands of years after alien species introduction. The presence of native or anciently introduced predators or competitors may be crucial for the recognition and development of adaptive behavior toward unknown predators or competitors of the same archetype (i.e. a set of species that occupy a similar ecological niche and show similar morphological and behavioral traits when interacting with other species. Here, we tested whether two squamates endemic to New Caledonia, a skink, Caledoniscincus austrocaledonicus, and a gecko, Bavayia septuiclavis, recognized and responded to the odor of two major invaders introduced into the Pacific islands, but not yet into New Caledonia. We chose one predator, the small Indian mongoose Herpestes javanicus and one competitor, the cane toad Rhinella marina, which belong respectively to the same archetype as the following two species already introduced into New Caledonia in the nineteenth century: the feral cat Felis catus and the golden bell frog Litoria aurea. Our experiment reveals that geckos are naïve with respect to the odors of both an unknown predator and an unknown competitor, as well as to the odors of a predator and a competitor they have lived with for centuries. In contrast, skinks seem to have lost some naïveté regarding the odor of a predator they have lived with for centuries and seem "predisposed" to avoid the odor of an unknown potential competitor. These results indicate that insular species living in contact with invasive alien species for centuries may be, although not systematically, predisposed toward developing adaptive behavior with respect to species belonging to the same archetype and introduced into

  9. Bladder cancer: the combination of chemotherapy and irradiation in the treatment of patients with muscle-invading tumors

    International Nuclear Information System (INIS)

    Shipley, William U.; Zietman, Anthony L.

    1995-01-01

    In the USA the recommended treatment for patients with muscle-invading transitional cell cancer of the bladder is usually radical cystectomy. Conservative surgery (transurethral resection and partial cystectomy), irradiation, and cis-platinum based systemic chemotherapy are, however, each effective for some patients. Although they provide the opportunity for bladder preservation, each modality, when used alone, is inferior to radical cystectomy in terms of local control and, perhaps, survival. Initial response and local control rates are improved when a multimodality approach is used. Up to 85% of patients selected for bladder sparing therapy on the basis of their initial response to chemo-radiation may keep their bladders. This figure could increase further when other powerful prognostic factors, such as the presence of hydronephrosis or carcinoma in situ, are taken into account in initial patient selection. Deferring the patient from immediate cystectomy does not appear to compromise survival. The most appropriate sequencing of radiation and chemotherapy is yet to be established. Concomitant cis-platinum and irradiation improves local control and bladder preservation when compared with irradiation alone but does not decrease the metastatic rate. It is hoped that the well recognized activity of cis-platinum based combination chemotherapy in advanced disease will translate into effective eradication of micrometastatic disease (known to be present in up to 40% of patients at diagnosis). This has yet to be clearly demonstrated in a randomized trial. The addition of combination chemotherapy to radiation does not increase bladder morbidity but carries a considerable systemic risk. Thus, despite promising phase II studies, until a survival benefit is proven in a randomized trial, neoadjuvant or adjuvant combination chemotherapy in conjunction with irradiation should continue to be regarded as experimental

  10. Habitat complexity and fish size affect the detection of Indo-Pacific lionfish on invaded coral reefs

    Science.gov (United States)

    Green, S. J.; Tamburello, N.; Miller, S. E.; Akins, J. L.; Côté, I. M.

    2013-06-01

    A standard approach to improving the accuracy of reef fish population estimates derived from underwater visual censuses (UVCs) is the application of species-specific correction factors, which assumes that a species' detectability is constant under all conditions. To test this assumption, we quantified detection rates for invasive Indo-Pacific lionfish ( Pterois volitans and P. miles), which are now a primary threat to coral reef conservation throughout the Caribbean. Estimates of lionfish population density and distribution, which are essential for managing the invasion, are currently obtained through standard UVCs. Using two conventional UVC methods, the belt transect and stationary visual census (SVC), we assessed how lionfish detection rates vary with lionfish body size and habitat complexity (measured as rugosity) on invaded continuous and patch reefs off Cape Eleuthera, the Bahamas. Belt transect and SVC surveys performed equally poorly, with both methods failing to detect the presence of lionfish in >50 % of surveys where thorough, lionfish-focussed searches yielded one or more individuals. Conventional methods underestimated lionfish biomass by ~200 %. Crucially, detection rate varied significantly with both lionfish size and reef rugosity, indicating that the application of a single correction factor across habitats and stages of invasion is unlikely to accurately characterize local populations. Applying variable correction factors that account for site-specific lionfish size and rugosity to conventional survey data increased estimates of lionfish biomass, but these remained significantly lower than actual biomass. To increase the accuracy and reliability of estimates of lionfish density and distribution, monitoring programs should use detailed area searches rather than standard visual survey methods. Our study highlights the importance of accounting for sources of spatial and temporal variation in detection to increase the accuracy of survey data from

  11. Irradiation as a quarantine treatment against the invader fruit fly (Bactrocera Invadens, Drew) in mangoes (Mangifera Indica L,)

    International Nuclear Information System (INIS)

    Odai, B.T.

    2010-06-01

    The detection of the African invader fly, Bactrocera invadens Drew, Tsuruta and White, in Ghana has led to limitations in the export of mango fruits from Ghana to other countries. The limitations ranging from increased control costs to outright rejection of exports has necessitated a study in the area of quarantine treatment. A study was conducted to ascertain the effectiveness of gamma radiation for control of Bactrocera invadens in fruit destined for export. Pupae were obtained from the incubation of mango fruits collected from various locations. Adults were reared and infestation levels were determined after fruits were exposed to 5, 10, 20 females in different cages. Late instar larvae in fruits were irradiated at 15, 25, 35, 45, 50, 60 and 75 Gy to determine an effective dose for B. invadens. The mortality of the fly was determined at the various doses to obtain a probit 9 figure of 68.06 Gy (rounded to 70 Gy). The confirmatory test for 3050 larvae endorsed the effective dose as the probit 9 dose. Non-infested mature green export grade mango fruits were irradiated with 0, 70 and 150 Gy to determine its effect on ascorbic acid and total acidity content, sweetness, colour, juiciness, sourness, aroma and firmness of the mango fruits. Ascorbic acid and total acidity were not irradiation dependent. Varietal differences (p 0.05) by irradiation. Varietal differences did not affect the acceptability of the sweetness, sourness and colour of the fruits (p>0.05). Storage days significantly affected (p<0.05) the acceptability of all the sensory attributes. (au)

  12. Count your eggs before they invade: identifying and quantifying egg clutches of two invasive apple snail species (Pomacea.

    Directory of Open Access Journals (Sweden)

    Colin H Kyle

    Full Text Available Winning the war against invasive species requires early detection of invasions. Compared to terrestrial invaders, aquatic species often thrive undetected under water and do not garner notice until too late for early action. However, fortunately for managers, apple snails (Family Ampullariidae, Genus Pomacea provide their own conspicuous sign of invasion in the form of vibrantly colored egg clutches. Managers can potentially use egg clutches laid in the riparian zone as a means of early detection and species identification. To facilitate such efforts, we quantified differences in characteristics (length, width, depth, mass, egg number of field-laid clutches for the two most common invasive species of apple snail, P. canaliculata and P. maculata, in native and non-native populations. Pomacea canaliculata native and non-native populations differed noticeably only in width. Native P. maculata clutches possessed significantly greater width, mass and eggs numbers compared with native P. canaliculata. Non-native P. maculata clutches significantly exceeded all other populations in all measured characteristics. Consequently, these traits may successfully distinguish between species. Fecundity data also allowed us to develop models that accurately estimated the number of eggs per clutch for each species based on clutch dimensions. We tested one, two and three dimensional models of clutches, including rendering a clutch as either a complete ellipsoid or an ellipsoid intersected by a cylinder to represent the oviposition site. Model comparisons found the product of length and depth, with a different function for each population, best predicted egg number for both species. Comparisons of egg number to clutch volume and mass implied non-native P. canaliculata may be food limited, while non-native P. maculata appeared to produce such enormous clutches by having access to greater nutrients than the native population. With these new tools, researchers and

  13. Fungal and bacterial contributions to nitrogen cycling in cheatgrass-invaded and uninvaded native sagebrush soils of the western USA

    Science.gov (United States)

    DeCrappeo, Nicole; DeLorenze, Elizabeth J.; Giguere, Andrew T; Pyke, David A.; Bottomley, Peter J.

    2017-01-01

    AimThere is interest in determining how cheatgrass (Bromus tectorum L.) modifies N cycling in sagebrush (Artemisia tridentata Nutt.) soils of the western USA.MethodsTo gain insight into the roles of fungi and bacteria in N cycling of cheatgrass-invaded and uninvaded sagebrush soils, the fungal protein synthesis inhibitor, cycloheximide (CHX), and the bacteriocidal compound, bronopol (BRO) were combined with a 15NH4+ isotope pool dilution approach.ResultsCHX reduced gross N mineralization to the same rate in both sagebrush and cheatgrass soils indicating a role for fungi in N mineralization in both soil types. In cheatgrass soils BRO completely inhibited gross N mineralization, whereas, in sagebrush soils a BRO-resistant gross N mineralization rate was detected that was slower than CHX sensitive gross N mineralization, suggesting that the microbial drivers of gross N mineralization were different in sagebrush and cheatgrass soils. Net N mineralization was stimulated to a higher rate in sagebrush than in cheatgrass soils by CHX, implying that a CHX inhibited N sink was larger in the former than the latter soils. Initial gross NH4+ consumption rates were reduced significantly by both CHX and BRO in both soil types, yet, consumption rates recovered significantly between 24 and 48 h in CHX-treated sagebrush soils. The recovery of NH4+ consumption in sagebrush soils corresponded with an increase in the rate of net nitrification.ConclusionsThese results suggest that cheatgrass invasion of sagebrush soils of the northern Great Basin reduces the capacity of the fungal N consumption sink, enhances the capacity of a CHX resistant N sink and alters the contributions of bacteria and fungi to gross N mineralization.

  14. Do species differ in their ability to coexist with the dominant alien Lupinus polyphyllus? A comparison between two distinct invaded ranges and a native range

    Directory of Open Access Journals (Sweden)

    Martin Hejda

    2013-06-01

    Full Text Available The community-level impacts of invasive plants are likely to vary depending on the character of native species of the target communities and their ability to thrive within the stands of the dominant alien invader. Therefore, I examined the response of native species richness to the cover of the dominant alien Lupinus polyphyllus in two distinct invaded ranges: Czech Republic (Central Europe and New Zealand. I compared the relation between native species richness and the cover of the dominant alien L. polyphyllus with that in its native range, Pacific Northwest, USA.In the native range, I found no response of native species richness to the cover of L. polyphyllus. In the Czech Republic (central Europe, the richness of native species related to it negativelly, but the relation was only marginally significant. Contrary to that, the richness of species native to New Zealand related to the cover of L. polyphyllus strongly negatively and the negative relation was significantly stronger than that of species native to Europe.Of the two invaded ranges, species native to New Zealand have been documented to be much more vulnerable to the conditions associated with the invasion and dominance of L. polyphyllus, compared to species native to central Europe. This principle has been shown both across these two invaded ranges and in New Zealand, where the aliens of european origin successfully coexist with the dominant invasive alien L. polyphyllus. Similarly, species in the native range of L. polyphyllus showed no relation to its cover, indicating their ability to thrive even in dense stands of this dominant species.

  15. One-stage surgery in combination with thoracic endovascular grafting and resection of T4 lung cancer invading the thoracic aorta and spine

    OpenAIRE

    Sato, Seijiro; Goto, Tatsuya; Koike, Terumoto; Okamoto, Takeshi; Shoji, Hirokazu; Ohashi, Masayuki; Watanabe, Kei; Tsuchida, Masanori

    2017-01-01

    A novel strategy of one-stage surgery in combination with thoracic endovascular grafting and resection for T4 lung cancer invading the thoracic aorta and spine is described. A 56-year-old man with locally advanced lung cancer infiltrating the aortic wall and spine underwent neoadjuvant chemotherapy and thoracic irradiation, followed by en bloc resection of the aortic wall and spine with thoracic endovascular grafting. He developed postoperative chylothorax, but there were no stent graft-relat...

  16. Invasive, naturalized and casual alien plants in southern Africa: a sum­mary based on the Southern African Plant Invaders Atlas (SAPIA

    Directory of Open Access Journals (Sweden)

    L. Henderson

    2007-08-01

    Full Text Available The primary objective of this publication is to provide an overview of the species identity, invasion status, geographical extent, and abundance of alien plants in South Africa, Swaziland and Lesotho, based on field records from 1979 to the end of 2000. The dataset is all the species records for the study area in the Southern African Plant Invaders Atlas (SAPIA database during this time period. A total of 548 naturalized and casual alien plant species were catalogued and invasion was recorded almost throughout the study area. Most invasion, in terms of both species numbers and total species abundance, was recorded along the southern, southwestern and eastern coastal belts and in the adjacent interior. This area includes the whole of the Fynbos and Forest Biomes, and the moister eastern parts of the Grassland and Savanna Biomes. This study reinforces previous studies that the Fynbos Biome is the most extensively invaded vegetation type in South Africa but it also shows that parts of Savanna and Grassland are as heavily invaded as parts of the Fynbos. The Fabaceae is prominent in all biomes and Acacia with 17 listed species, accounts for a very large proportion of all invasion. Acacia mearmii was by far the most prominent invasive species in the study area, followed by A. saligna, Lantana camara, A. cyclops, Opuntia ficus-indica. Solarium mauritianum, Populus alba/xcanescens, Melia azedarach, A. dealbata and species of Prosopis.

  17. Synergistic interactions of CO2 enrichment and nitrogen deposition promote growth and ecophysiological advantages of invading Eupatorium adenophorum in Southwest China.

    Science.gov (United States)

    Lei, Yan-bao; Wang, Wei-bin; Feng, Yu-long; Zheng, Yu-long; Gong, He-de

    2012-10-01

    Global environmental change and ongoing biological invasions are the two prominent ecological issues threatening biodiversity worldwide, and investigations of their interaction will aid to predict plant invasions and inform better management strategies in the future. In this study, invasive Eupatorium adenophorum and native congener E. stoechadosmum were compared at ambient and elevated atmospheric carbon dioxide (CO(2)) concentrations combined with three levels of nitrogen (N; reduced, control and increased) in terms of growth, energy gain, and cost. Compared with E. stoechadosmum, E. adenophorum adopted a quicker-return energy-use strategy, i.e. higher photosynthetic energy-use efficiency and shorter payback time. Lower leaf mass per area may be a pivotal trait for the invader, which contributed to an increased N allocation to Rubisco at the expense of cell walls and therefore to higher photosynthetic energy gain. CO(2) enrichment and N deposition synergistically promoted plant growth and influenced some related ecophysiological traits, and the synergistic effects were greater for the invader than for the native congener. Reducing N availability by applying sugar eliminated the advantages of the invader over its native congener at both CO(2) levels. Our results indicate that CO(2) enrichment and N deposition may exacerbate E. adenophorum's invasion in the future, and manipulating environmental resources such as N availability may be a feasible tool for managing invasion impacts of E. adenophorum.

  18. Reconstruction of a Marjolin Ulcer Defect of the Scalp Invading Brain and Causing Brain Abscess Formation Using Free Latissimus Dorsi Flap.

    Science.gov (United States)

    Tenekeci, Goktekin; Sari, Alper; Hamzaoglu, Vural; Ozalp, Hakan

    2017-07-01

    Marjolin ulcers are known as aggressive malignant tumors that mostly arise over chronic wounds and cutaneous scars. Brain abscess is a serious medical condition that requires surgical drainage along with antibiotic treatment. Here, we report a case with a Marjolin ulcer located over the right parietal bone with intracranial abscess formation along with tumor invasion into brain parenchyma. This patient was a 64-year-old man and had a 4 × 4 cm open wound on his scalp from which a purulent discharge was coming. This wound required surgical excision with security margins, resection of bone, evacuation of the cystic cavity, and excision of the walls of the cystic cavity, which were invaded by the tumor. Duraplasty and reconstruction of the defect with a free lattisimus dorsi flap are performed. To the best of our knowledge, the case reported here is unique because of the formation of brain abscess in the background of a long-lasting Marjolin ulcer invading brain parenchyma. It must be remembered that on the background of cutaneous scars located over the scalp, a Marjolin ulcer may develop, and if left untreated, tumor cells may invade even the brain parenchyma. Long-term asymptomatic brain infections may also accompany the given scenario, and complicate differential diagnosis.

  19. Matrix density alters zyxin phosphorylation, which limits peripheral process formation and extension in endothelial cells invading 3D collagen matrices.

    Science.gov (United States)

    Abbey, Colette A; Bayless, Kayla J

    2014-09-01

    This study was designed to determine the optimal conditions required for known pro-angiogenic stimuli to elicit successful endothelial sprouting responses. We used an established, quantifiable model of endothelial cell (EC) sprout initiation where ECs were tested for invasion in low (1 mg/mL) and high density (5 mg/mL) 3D collagen matrices. Sphingosine 1-phosphate (S1P) alone, or S1P combined with stromal derived factor-1α (SDF) and phorbol ester (TPA), elicited robust sprouting responses. The ability of these factors to stimulate sprouting was more effective in higher density collagen matrices. S1P stimulation resulted in a significant increase in invasion distance, and with the exception of treatment groups containing phorbol ester, invasion distance was longer in 1mg/mL compared to 5mg/mL collagen matrices. Closer examination of cell morphology revealed that increasing matrix density and supplementing with SDF and TPA enhanced the formation of multicellular structures more closely resembling capillaries. TPA enhanced the frequency and size of lumen formation and correlated with a robust increase in phosphorylation of p42/p44 Erk kinase, while S1P and SDF did not. Also, a higher number of significantly longer extended processes formed in 5mg/mL compared to 1mg/mL collagen matrices. Because collagen matrices at higher density have been reported to be stiffer, we tested for changes in the mechanosensitive protein, zyxin. Interestingly, zyxin phosphorylation levels inversely correlated with matrix density, while levels of total zyxin did not change significantly. Immunofluorescence and localization studies revealed that total zyxin was distributed evenly throughout invading structures, while phosphorylated zyxin was slightly more intense in extended peripheral processes. Silencing zyxin expression increased extended process length and number of processes, while increasing zyxin levels decreased extended process length. Altogether these data indicate that ECs

  20. Impacts of insect biological control on soil N transformations in Tamarix-invaded ecosystems in the Great Basin

    Science.gov (United States)

    Understanding the impacts of insect biological control of Tamarix spp. on soil nitrogen (N) transformations is important because changes to N supply could alter plant community succession. We investigated short-term and longer-term impacts of herbivory by the northern tamarisk beetle (Diorhabda cari...

  1. "Fate: The short film"

    OpenAIRE

    Maya Quintana, Jennifer

    2014-01-01

    "Fate: The Short Film" is a four minute short film which reflects the idea that nobody can escape from the fate. It has a good picture and sound quality with an understandable message for all public and with the collaboration of actors, filmmaker, stylist, script advisor and media technician.

  2. [Shunt and short circuit].

    Science.gov (United States)

    Rangel-Abundis, Alberto

    2006-01-01

    Shunt and short circuit are antonyms. In French, the term shunt has been adopted to denote the alternative pathway of blood flow. However, in French, as well as in Spanish, the word short circuit (court-circuit and cortocircuito) is synonymous with shunt, giving rise to a linguistic and scientific inconsistency. Scientific because shunt and short circuit made reference to a phenomenon that occurs in the field of the physics. Because shunt and short circuit are antonyms, it is necessary to clarify that shunt is an alternative pathway of flow from a net of high resistance to a net of low resistance, maintaining the stream. Short circuit is the interruption of the flow, because a high resistance impeaches the flood. This concept is applied to electrical and cardiovascular physiology, as well as to the metabolic pathways.

  3. Idiopathic short stature

    Directory of Open Access Journals (Sweden)

    Vlaški Jovan

    2013-01-01

    Full Text Available Growth is a complex process and the basic characteristic of child- hood growth monitoring provides insight into the physiological and pathological events in the body. Statistically, the short stature means departure from the values of height for age and sex (in a particular environment, which is below -2 standard deviation score, or less than -2 standard deviation, i.e. below the third percentile. Advances in molecular genetics have contributed to the improvement of diagnostics in endocrinology. Analysis of patients’ genotypes should not be performed before taking a classical history, detailed clinical examination and appropriate tests. In patients with idiopathic short stature specific causes are excluded, such as growth hormone deficiency, Turner syndrome, short stature due to low birth weight, intrauterine growth retardation, small for gestational age, dysmorphology syndromes and chronic childhood diseases. The exclusion of abovementioned conditions leaves a large number of children with short stature whose etiology includes patients with genetic short stature or familial short stature and those who are low in relation to genetic potential, and who could also have some unrecognized endocrine defect. Idiopathic short stature represents a short stature of unknown cause of heterogeneous etiology, and is characterized by a normal response of growth hormone during stimulation tests (>10 ng/ml or 20 mJ/l, without other disorders, of normal body mass and length at birth. In idiopathic short stature standard deviation score rates <-2.25 (-2 to -3 or <1.2 percentile. These are also criteria for the initiation of growth hormone therapy. In children with short stature there is also the presence of psychological and social suffering. Goals of treatment with growth hormone involve achieving normal height and normal growth rate during childhood.

  4. Imaging in short stature.

    Science.gov (United States)

    Chaudhary, Vikas; Bano, Shahina

    2012-09-01

    Short stature can be a sign of disease, disability, and social stigma causing psychological stress. It is important to have an early diagnosis and treatment. Short stature may result from skeletal dysplasias, endocrine disorders, may be familial, or may be the result of malnutrition and chronic illnesses. A team effort of the healthcare professionals like pediatricians, endocrinologists, radiologists, and pathologists is required to diagnose, treat and monitor various pathological conditions associated with growth abnormality. In this review, we have discussed the role of imaging in diagnosing and characterizing various pathological conditions associated with short stature.

  5. Imaging in short stature

    Directory of Open Access Journals (Sweden)

    Vikas Chaudhary

    2012-01-01

    Full Text Available Short stature can be a sign of disease, disability, and social stigma causing psychological stress. It is important to have an early diagnosis and treatment. Short stature may result from skeletal dysplasias, endocrine disorders, may be familial, or may be the result of malnutrition and chronic illnesses. A team effort of the healthcare professionals like pediatricians, endocrinologists, radiologists, and pathologists is required to diagnose, treat and monitor various pathological conditions associated with growth abnormality. In this review, we have discussed the role of imaging in diagnosing and characterizing various pathological conditions associated with short stature.

  6. Short bowel syndrome

    International Nuclear Information System (INIS)

    Engels, L.G.J.B.

    1983-01-01

    This thesis describes some aspects of short bowel syndrome. When approximately 1 m or less small bowel is retained after extensive resection, a condition called short bowel syndrome is present. Since the advent of parenteral nutrition, the prognosis of patients with a very short bowel has dramatically improved. Patients with 40 to 100 cm remaining jejunum and/or ileum can generally be maintained with oral nutrition due to increased absorption of the small bowel remnant as result of intestinal adaptation. This study reports clinical, biochemical and nutritional aspects of short bowel patients on oral or parenteral nutrition, emphasizing data on absorption of various nutrients and on bone metabolism. Furthermore, some technical apsects concerning long-term parenteral nutrition are discussed. (Auth.)

  7. Catapults fall short

    Science.gov (United States)

    Gibson, Marcus

    2018-01-01

    In reply to the news story "UK Catapults fall short, claims review of technology centres", which describes an independent review that criticized the management of the UK's network of technology innovation centres.

  8. Short-cut math

    CERN Document Server

    Kelly, Gerard W

    1984-01-01

    Clear, concise compendium of about 150 time-saving math short-cuts features faster, easier ways to add, subtract, multiply, and divide. Each problem includes an explanation of the method. No special math ability needed.

  9. Imaging in short stature

    OpenAIRE

    Vikas Chaudhary; Shahina Bano

    2012-01-01

    Short stature can be a sign of disease, disability, and social stigma causing psychological stress. It is important to have an early diagnosis and treatment. Short stature may result from skeletal dysplasias, endocrine disorders, may be familial, or may be the result of malnutrition and chronic illnesses. A team effort of the healthcare professionals like pediatricians, endocrinologists, radiologists, and pathologists is required to diagnose, treat and monitor various pathological conditions ...

  10. From effective biocontrol agent to successful invader: the harlequin ladybird (Harmonia axyridis as an example of good ideas that could go wrong

    Directory of Open Access Journals (Sweden)

    Morelia Camacho-Cervantes

    2017-05-01

    Full Text Available The use of biological control agents to control pests is an alternative to pesticides and a tool to manage invasive alien species. However, biocontrol agents can themselves become invasive species under certain conditions. The harlequin ladybird (Harmonia axyridis is a native Asian biocontrol agent that has become a successful invader. We reviewed articles containing “Harmonia axyridis” to gather information on its presence and surveyed entomologists researching Coccinellidae around the world to investigate further insights about the current distribution, vectors of introduction, habitat use and threats this species pose. The harlequin ladybird has established populations in at least 59 countries outside its native range. Twenty six percent of the surveyed scientists considered it a potential threat to native Coccinellidae. Published studies and scientists suggest Adalia bipunctata, native to Europe, is under the highest risk of population declines. Strict policies should be incorporated to prevent its arrival to non-invaded areas and to prevent further expansion range. Managing invasive species is a key priority to prevent biodiversity loss and promote ecosystem services.

  11. Invading stacking primer: A trigger for high-efficiency isothermal amplification reaction with superior selectivity for detecting microRNA variants.

    Science.gov (United States)

    Liu, Weipeng; Zhu, Minjun; Liu, Hongxing; Wei, Jitao; Zhou, Xiaoming; Xing, Da

    2016-07-15

    Searching for a strategy to enhance the efficiency of nucleic acid amplification and achieve exquisite discrimination of nucleic acids at the single-base level for biological detection has become an exciting research direction in recent years. Here, we have developed a simple and universal primer design strategy which produces a fascinating effect on isothermal strand displacement amplification (iSDA). We refer to the resultant primer as "invading stacking primer (IS-Primer)" which is based on contiguous stacking hybridization and toehold-mediated exchange reaction and function by merely changing the hybridization location of the primer. Using the IS-Primer, the sensitivity in detecting the target miR-21 is improved approximately five fold compared with the traditional iSDA reaction. It was further demonstrated that the IS-Primer acts as an invading strand to initiate branch migration which can increase the efficiency of the untwisting of the hairpin probe. This effect is equivalent to reducing the free energy of the stem, and the technique shows superior selectivity for single-base mismatches. By demonstrating the enhanced effect of the IS-Primer in the iSDA reaction, this work may provide a potentially new avenue for developing more sensitive and selective nucleic acids assays. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Seasonal fluctuations of some biological traits of the invader Caprella scaura (Crustacea: Amphipoda: Caprellidae in the Mar Piccolo of Taranto (Ionian Sea, southern Italy

    Directory of Open Access Journals (Sweden)

    Ermelinda Prato

    2013-03-01

    Full Text Available Caprella scaura is an epifaunal amphipod crustacean that originates in the western Indian Ocean and has spread throughout the world, but very little is known about fundamental aspects of its biology. This paper is the first presentation of its life history traits in an invaded region. The study was conducted in the Mar Piccolo basin (southern Italy, Ionian Sea, over a one-year period. All biological parameters showed a strong seasonal pattern, breeding peaked twice during the year and the number of eggs in the ventral brood pouch ranged from 5 to 72. The sex ratio was generally close to 1:1. A strong correlation between total length of ovigerous females and number of eggs was observed. The mean length of both mature males and mature females was 10.63 and 7.70 mm, respectively. The results of this study showed that the population dynamics of this species was not dissimilar to that of other caprellids or marine epifaunal Crustacea. This caprellid has given rise to a stable population in the Mar Piccolo; it was present all year round in the study area but its density suggests that it is not yet a strong invader.

  13. Middle-preserving pancreatectomy for advanced transverse colon cancer invading the duodenun and non-functioning endocrine tumor in the pancreatic tail.

    Science.gov (United States)

    Noda, Hiroshi; Kato, Takaharu; Kamiyama, Hidenori; Toyama, Nobuyuki; Konishi, Fumio

    2011-02-01

    A 73-year-old female was referred to our hospital with a diagnosis of advanced transverse colon cancer with severe anemia and body weight loss. Preoperative evaluations, including colonoscopy, gastroduodenoscopy, and computed tomography, revealed not only a transverse colon cancer massively invading the duodenum, but also a non-functioning endocrine tumor in the pancreatic tail. We performed middle-preserving pancreatectomy (MPP) with right hemicolectomy for these tumors with a curative intent. After the resection, about 6 cm of the body of the pancreas was preserved, and signs of diabetes mellitus have not appeared. The postoperative course was complicated by a grade B pancreatic fistula, but this was successfully treated with conservative management. After a 33-day hospital stay, the patient returned to daily life without signs of pancreatic exocrine insufficiency. Although the long-term follow-up of the patient is indispensable, in this case, MPP might be able to lead to the curative resection of transverse colon cancer massively invading the duodenum and non-functioning endocrine tumor in the pancreatic tail with preservation of pancreatic function.

  14. Measurement of short bunches

    International Nuclear Information System (INIS)

    Wang, D.X.

    1996-01-01

    In recent years, there has been increasing interest in short electron bunches for different applications such as short wavelength FELs, linear colliders, and advanced accelerators such as laser or plasma wakefield accelerators. One would like to meet various requirements such as high peak current, low momentum spread, high luminosity, small ratio of bunch length to plasma wavelength, and accurate timing. Meanwhile, recent development and advances in RF photoinjectors and various bunching schemes make it possible to generate very short electron bunches. Measuring the longitudinal profile and monitoring bunch length are critical to understand the bunching process and longitudinal beam dynamics, and to commission and operate such short bunch machines. In this paper, several commonly used measurement techniques for subpicosecond bunches and their relative advantages and disadvantages are discussed. As examples, bunch length related measurements at Jefferson Lab are presented. At Jefferson Lab, bunch lengths as short as 84 fs have been systematically measured using a zero-phasing technique. A highly sensitive Coherent Synchrotron Radiation (CSR) detector has been developed to noninvasively monitor bunch length for low charge bunches. Phase transfer function measurements provide a means of correcting RF phase drifts and reproducing RF phases to within a couple of tenths of a degree. The measurement results are in excellent agreement with simulations. A comprehensive bunch length control scheme is presented. (author)

  15. Measurement of short bunches

    International Nuclear Information System (INIS)

    Wang, D.X.

    1996-01-01

    In recent years, there has been increasing interest in short electron bunches for different applications such as short wavelength FELs, linear colliders, and advanced accelerators such as laser or plasma wakefield accelerators. One would like to meet various requirements such as high peak current, low momentum spread, high luminosity, small ratio of bunch length to plasma wavelength, and accurate timing. Meanwhile, recent development and advances in RF photoinjectors and various bunching schemes make it possible to generate very short electron bunches. Measuring the longitudinal profile and monitoring bunch length are critical to understand the bunching process and longitudinal beam dynamics, and to commission and operate such short bunch machines. In this paper, several commonly used measurement techniques for subpicosecond bunches and their relative advantages and disadvantages are discussed. As examples, bunch length related measurements at Jefferson lab are presented. At Jefferson Lab, bunch lengths s short as 84 fs have been systematically measured using a zero-phasing technique. A highly sensitive Coherent Synchrotron Radiation (CSR) detector has been developed to noninvasively monitor bunch length for low charge bunches. Phase transfer function measurements provide a means of correcting RF phase drifts and reproducing RF phases to within a couple of tenths of a degree. The measurement results are in excellent agreement with simulations. A comprehensive bunch length control scheme is presented

  16. Congenital Short QT Syndrome

    Directory of Open Access Journals (Sweden)

    Lia Crotti

    2010-02-01

    Full Text Available The Short QT Syndrome is a recently described new genetic disorder, characterized by abnormally short QT interval, paroxysmal atrial fibrillation and life threatening ventricular arrhythmias. This autosomal dominant syndrome can afflict infants, children, or young adults; often a remarkable family background of cardiac sudden death is elucidated. At electrophysiological study, short atrial and ventricular refractory periods are found, with atrial fibrillation and polymorphic ventricular tachycardia easily induced by programmed electrical stimulation. Gain of function mutations in three genes encoding K+ channels have been identified, explaining the abbreviated repolarization seen in this condition: KCNH2 for Ikr (SQT1, KCNQ1 for Iks (SQT2 and KCNJ2 for Ik1 (SQT3. The currently suggested therapeutic strategy is an ICD implantation, although many concerns exist for asymptomatic patients, especially in pediatric age. Pharmacological treatment is still under evaluation; quinidine has shown to prolong QT and reduce the inducibility of ventricular arrhythmias, but awaits additional confirmatory clinical data.

  17. Short notice inspections

    International Nuclear Information System (INIS)

    Pouchkarev, V.

    1998-01-01

    For 30 years the IAEA safeguards system have evolved and have been strengthened by the regular introduction of new methods and techniques, improving both its effectiveness and efficiency. The member States of the IAEA have indicated their willingness to accept new obligations and associated technical measure that greatly strengthen the nuclear safeguards system. One element of this is the extent to which the IAEA inspectors have physical access to relevant locations for the purpose of providing independent verification of the exclusively peaceful intent of a State nuclear program. The Protocol to Safeguards granted new legal authority with respect to information on, and short notice inspector access to, all buildings on a nuclear site and administrative agreements that improve the process of designating inspectors and IAEA access to modern means of communication. This report is a short description of unannounced or short notice inspections as measures on which the new strengthened and cost efficient system will be based

  18. Detecting short circuits during assembly

    Science.gov (United States)

    Deboo, G. J.

    1980-01-01

    Detector circuit identifies shorts between bus bars of electronic equipment being wired. Detector sounds alarm and indicates which planes are shorted. Power and ground bus bars are scanned continuously until short circuit occurs.

  19. Short wavelength FELS

    International Nuclear Information System (INIS)

    Sheffield, R.L.

    1991-01-01

    The generation of coherent ultraviolet and shorter wavelength light is presently limited to synchrotron sources. The recent progress in the development of brighter electron beams enables the use of much lower energy electron rf linacs to reach short-wavelengths than previously considered possible. This paper will summarize the present results obtained with synchrotron sources, review proposed short- wavelength FEL designs and then present a new design which is capable of over an order of magnitude higher power to the extreme ultraviolet. 17 refs., 10 figs

  20. Short wavelength FELS

    Energy Technology Data Exchange (ETDEWEB)

    Sheffield, R.L.

    1991-01-01

    The generation of coherent ultraviolet and shorter wavelength light is presently limited to synchrotron sources. The recent progress in the development of brighter electron beams enables the use of much lower energy electron rf linacs to reach short-wavelengths than previously considered possible. This paper will summarize the present results obtained with synchrotron sources, review proposed short- wavelength FEL designs and then present a new design which is capable of over an order of magnitude higher power to the extreme ultraviolet. 17 refs., 10 figs.

  1. Short-sighted evolution of virulence in parasitic honeybee workers ( Apis mellifera capensis Esch.)

    Science.gov (United States)

    Moritz, Robin F. A.; Pirk, Christian W. W.; Hepburn, H. Randall; Neumann, Peter

    2008-06-01

    The short-sighted selection hypothesis for parasite virulence predicts that winners of within-host competition are poorer at transmission to new hosts. Social parasitism by self-replicating, female-producing workers occurs in the Cape honeybee Apis mellifera capensis, and colonies of other honeybee subspecies are susceptible hosts. We found high within-host virulence but low transmission rates in a clone of social parasitic A. m. capensis workers invading the neighbouring subspecies A. m. scutellata. In contrast, parasitic workers from the endemic range of A. m. capensis showed low within-host virulence but high transmission rates. This suggests a short-sighted selection scenario for the host-parasite co-evolution in the invasive range of the Cape honeybee, probably facilitated by beekeeping-assisted parasite transmission in apiaries.

  2. Plant litter chemistry alters the content and composition of organic carbon associated with soil mineral and aggregate fractions in invaded ecosystems.

    Science.gov (United States)

    Tamura, Mioko; Suseela, Vidya; Simpson, Myrna; Powell, Brian; Tharayil, Nishanth

    2017-10-01

    Through the input of disproportionate quantities of chemically distinct litter, invasive plants may potentially influence the fate of organic matter associated with soil mineral and aggregate fractions in some of the ecosystems they invade. Although context dependent, these native ecosystems subjected to prolonged invasion by exotic plants may be instrumental in distinguishing the role of plant-microbe-mineral interactions from the broader edaphic and climatic influences on the formation of soil organic matter (SOM). We hypothesized that the soils subjected to prolonged invasion by an exotic plant that input recalcitrant litter (Japanese knotweed, Polygonum cuspidatum) would have a greater proportion of plant-derived carbon (C) in the aggregate fractions, as compared with that in adjacent soil inhabited by native vegetation that input labile litter, whereas the soils under an invader that input labile litter (kudzu, Pueraria lobata) would have a greater proportion of microbial-derived C in the silt-clay fraction, as compared with that in adjacent soils that receive recalcitrant litter. At the knotweed site, the higher C content in soils under P. cuspidatum, compared with noninvaded soils inhabited by grasses and forbs, was limited to the macroaggregate fraction, which was abundant in plant biomarkers. The noninvaded soils at this site had a higher abundance of lignins in mineral and microaggregate fractions and suberin in the macroaggregate fraction, partly because of the greater root density of the native species, which might have had an overriding influence on the chemistry of the above-ground litter input. At the kudzu site, soils under P. lobata had lower C content across all size fractions at a 0-5 cm soil depth despite receiving similar amounts of Pinus litter. Contrary to our prediction, the noninvaded soils receiving recalcitrant Pinus litter had a similar abundance of plant biomarkers across both mineral and aggregate fractions, potentially because of

  3. Congenital Short QT Syndrome

    Directory of Open Access Journals (Sweden)

    Charles Antzelevitch

    2004-04-01

    Full Text Available Long QT intervals in the ECG have long been associated with sudden cardiac death. The congenital long QT syndrome was first described in individuals with structurally normal hearts in 1957.1 Little was known about the significance of a short QT interval. In 1993, after analyzing 6693 consecutive Holter recordings Algra et al concluded that an increased risk of sudden death was present not only in patients with long QT interval, but also in patients with short QT interval (<400 ms.2 Because this was a retrospective analysis, further evaluation of the data was not possible. It was not until 2000 that a short-QT syndrome (SQTS was proposed as a new inherited clinical syndrome by Gussak et al.3 The initial report was of two siblings and their mother all of whom displayed persistently short QT interval. The youngest was a 17 year old female presenting with several episodes of paroxysmal atrial fibrillation requiring electrical cardioversion.3 Her QT interval measured 280 msec at a heart rate of 69. Her 21 year old brother displayed a QT interval of 272 msec at a heart rate of 58, whereas the 51 year old mother showed a QT of 260 msec at a heart rate of 74. The authors also noted similar ECG findings in another unrelated 37 year old patient associated with sudden cardiac death.

  4. SHORT COMMUNICATION POTENTIOMETRIC DETERMINATION ...

    African Journals Online (AJOL)

    a

    SHORT COMMUNICATION. POTENTIOMETRIC DETERMINATION OF K+ IONS USING A K+-SELECTIVE. ELECTRODE WITH MACROCYCLIC LIQUID MEMBRANE. Cezar Spinu*, Marian Isvoranu, Maria Pleniceanu and Cristian Tigae. Faculty of Chemistry, University of Craiova, A.I. Cuza 13, Craiova, Romania. (Received ...

  5. Biorefineries: A Short Introduction.

    Science.gov (United States)

    Wagemann, Kurt; Tippkötter, Nils

    2018-04-13

    The terms bioeconomy and biorefineries are used for a variety of processes and developments. This short introduction is intended to provide a delimitation and clarification of the terminology as well as a classification of current biorefinery concepts. The basic process diagrams of the most important biorefinery types are shown.

  6. Structural and Functional Characterization of an Archaeal Clustered Regularly Interspaced Short Palindromic Repeat (CRISPR)-associated Complex for Antiviral Defense (CASCADE)

    DEFF Research Database (Denmark)

    Lintner, Nathanael G; Kerou, Melina; Brumfield, Susan K

    2011-01-01

    In response to viral infection, many prokaryotes incorporate fragments of virus-derived DNA into loci called clustered regularly interspaced short palindromic repeats (CRISPRs). The loci are then transcribed, and the processed CRISPR transcripts are used to target invading viral DNA and RNA....... The Escherichia coli "CRISPR-associated complex for antiviral defense" (CASCADE) is central in targeting invading DNA. Here we report the structural and functional characterization of an archaeal CASCADE (aCASCADE) from Sulfolobus solfataricus. Tagged Csa2 (Cas7) expressed in S. solfataricus co-purifies with Cas5......a-, Cas6-, Csa5-, and Cas6-processed CRISPR-RNA (crRNA). Csa2, the dominant protein in aCASCADE, forms a stable complex with Cas5a. Transmission electron microscopy reveals a helical complex of variable length, perhaps due to substoichiometric amounts of other CASCADE components. A recombinant Csa2...

  7. [A case of sigmoid colon cancer invading urinary bladder treated with preoperative mFOLFOX6 and urinary bladder conserving surgery].

    Science.gov (United States)

    Nishino, Takeshi; Katayama, Kazuhisa; Takahashi, Yuji; Tanaka, Takashi

    2012-02-01

    A 69-year-old man visited our hospital because of melena and anemia. Colonoscopy revealed a type 3 tumor at sigmoid colon, and by abdominal CT, we detected a sigmoid colon cancer invading the urinary bladder with a single liver metastasis. The patient required sigmoidectomy with partial hepatectomy and total urinary bladder resection. Preoperative chemotherapy with mFOLFOX6 was initiated as a part of multidisciplinary therapy. After the 6th course was completed, CT revealed a reduction in the primary tumor's size and the disappearance of liver metastasis. After the 8th course was completed, we performed urinary bladder conserving sigmoidectomy. The pathological diagnosis of the surgical specimen was tub1, pSS, ly0, v0, pN0, and pStage II. Down-sizing chemotherapy might improve the quality of life(QOL)of colon cancer patients with extensive invasion of the urinary bladder.

  8. Listeria monocytogenes strains encoding premature stop codons in inlA invade mice and guinea pig fetuses in orally dosed dams

    DEFF Research Database (Denmark)

    Holch, Anne; Ingmer, Hanne; Licht, Tine Rask

    2013-01-01

    potential of a group of food-processing persistent L. monocytogenes strains encoding a premature stop codon in inlA (encoding internalin A) by using two orally dosed models, pregnant mice and pregnant guinea pigs. A food-processing persistent strain of L. monocytogenes invaded placentas (n = 58; 10...... % positive) and fetuses (3 % positive) of pregnant mice (n = 9 animals per strain), similar to a genetically manipulated murinized strain, EGD-e InlAm* (n = 61; 3 and 2 %, respectively). In pregnant guinea pigs (n = 9 animals per bacterial strain), a maternofetal strain (from a human fetal clinical fatal...... case) was isolated from 34 % of placenta samples (n = 50), whereas both food-processing persistent strains were found in 5 % of placenta samples (n = 36 or 37). One of the food-processing persistent strains, N53-1, was found in up to 8 % of guinea pig fetal liver and brain samples, whereas...

  9. Phyto chemical study and evaluation of allelopathy in Memora peregrina, 'ciganinha', Bignoniaceae, an invading species in pastures in Mato Grosso do Sul, Brazil

    International Nuclear Information System (INIS)

    Grassi, Rafaela Ferreira; Resende, Ubirazilda Maria; Silva, Walciane da; Macedo, Maria Ligia Rodrigues; Butera, Ana Paola; Tulli, Elayne de Oliveira; Saffran, Francis Paes; Siqueira, Joao Maximo de

    2005-01-01

    Memora peregrina (local name: 'ciganinha' - Bignoniaceae) is a weed that often invades pastures in the Brazilian state of Mato Grosso do Sul. From its leaves and subterranean parts, the following compounds were isolated: allantoin (20.7 w/w in subterranean parts), the iridoid 6β-hydroxyipolamiide, hyperin, 3'-O-methylhyperin, 4-hydroxy-N-methylproline, β-sitosterol, α-amirin and β-amirin, and lupeol. Allantoin exhibited an activity of inducing germination in seeds of Lactuca sativa used as a biological model, and the iridoid showed moderate activity in the larval development of Anagasta kuehniella. These results, associated with this plant's behavior, are suggestive of the occurrence of adaptive and competitive strategies in relation to other plant species. (author)

  10. Nitrogen limitation, 15N tracer retention, and growth response in intact and Bromus tectorum-invaded Artemisia tridentata ssp. wyomingensis communities

    Science.gov (United States)

    Witwicki, Dana L.; Doescher, Paul S.; Pyke, David A.; DeCrappeo, Nicole M.; Perakis, Steven S.

    2012-01-01

    Annual grass invasion into shrub-dominated ecosystems is associated with changes in nutrient cycling that may alter nitrogen (N) limitation and retention. Carbon (C) applications that reduce plant-available N have been suggested to give native perennial vegetation a competitive advantage over exotic annual grasses, but plant community and N retention responses to C addition remain poorly understood in these ecosystems. The main objectives of this study were to (1) evaluate the degree of N limitation of plant biomass in intact versus B. tectorum-invaded sagebrush communities, (2) determine if plant N limitation patterns are reflected in the strength of tracer 15N retention over two growing seasons, and (3) assess if the strength of plant N limitation predicts the efficacy of carbon additions intended to reduce soil N availability and plant growth. Labile C additions reduced biomass of exotic annual species; however, growth of native A. tridentata shrubs also declined. Exotic annual and native perennial plant communities had divergent responses to added N, with B. tectorum displaying greater ability to use added N to rapidly increase aboveground biomass, and native perennials increasing their tissue N concentration but showing little growth response. Few differences in N pools between the annual and native communities were detected. In contrast to expectations, however, more 15N was retained over two growing seasons in the invaded annual grass than in the native shrub community. Our data suggest that N cycling in converted exotic annual grasslands of the northern Intermountain West, USA, may retain N more strongly than previously thought.

  11. Extended resections of non-small cell lung cancers invading the aorta, pulmonary artery, left atrium, or esophagus: can they be justified?

    Science.gov (United States)

    Reardon, Emily S; Schrump, David S

    2014-11-01

    T4 tumors that invade the heart, great vessels, or esophagus comprise a heterogenous group of locally invasive lung cancers. Prognosis depends on nodal status; this relationship has been consistently demonstrated in many of the small series of extended resection. Current National Comprehensive Cancer Network guidelines do not recommend surgery for T4 extension with N2-3 disease (stage IIIB). However, biopsy-proven T4 N0-1 (stage IIIA) may be operable. Localized tumors with invasion of the aorta, pulmonary artery, left atrium, or esophagus represent a small subset of T4 disease. Acquiring sufficient randomized data to provide statistical proof of a survival advantage for patients undergoing extended resections for these neoplasms will likely never be possible.Therefore, we are left to critically analyze current documented experience to make clinical decisions on a case-by-case basis.It is clear that the operative morbidity and mortality of extended resections for locally advanced T4 tumors have significantly improved over time,yet the risks are still high. The indications for such procedures and the anticipated outcomes should be clearly weighed in terms of potential perioperative complications and expertise of the surgical team. Patients with T4 N0-1 have the best prognosis and with complete resection may have the potential for cure. The use of induction therapy and surgery for advanced T4 tumors may improve survival. Current data suggest that for tumors that invade the aorta, pulmonary artery,left atrium, or esophagus, resection should be considered in relation to multidisciplinary care.For properly selected patients receiving treatment at high volume, experienced centers, extended resections may be warranted. Published by Elsevier Inc.

  12. Short pulse neutron generator

    Science.gov (United States)

    Elizondo-Decanini, Juan M.

    2016-08-02

    Short pulse neutron generators are described herein. In a general embodiment, the short pulse neutron generator includes a Blumlein structure. The Blumlein structure includes a first conductive plate, a second conductive plate, a third conductive plate, at least one of an inductor or a resistor, a switch, and a dielectric material. The first conductive plate is positioned relative to the second conductive plate such that a gap separates these plates. A vacuum chamber is positioned in the gap, and an ion source is positioned to emit ions in the vacuum chamber. The third conductive plate is electrically grounded, and the switch is operable to electrically connect and disconnect the second conductive plate and the third conductive plate. The at least one of the resistor or the inductor is coupled to the first conductive plate and the second conductive plate.

  13. Short-term memory

    Science.gov (United States)

    Toulouse, G.

    This is a rather bold attempt to bridge the gap between neuron structure and psychological data. We try to answer the question: Is there a relation between the neuronal connectivity in the human cortex (around 5,000) and the short-term memory capacity (7±2)? Our starting point is the Hopfield model (Hopfield 1982), presented in this volume by D.J. Amit.

  14. Initial Results of Bladder Preserving Approach by Chemo-Radiotherapy in Patients with Muscle Invading Transitional Cell Carcinoma

    International Nuclear Information System (INIS)

    Aboziada, M.A.; Hamza, H.; Abdlrahem, A.M.

    2009-01-01

    This study was conducted to test the efficacy and tolerability of trimodality treatment for invasive bladder cancer and to test the possibility of bladder sparing. Methods: This study had been carried out on 50 patients with transitional cell carcinoma (TCC) stage T2- T3 tumors with adequate performance status and renal function. All patients were subjected to maximum transurethral resection of bladder tumors (TURBT). Patients were then subjected to chemo-radiation that was executed in two treatment phases. Phase I was external radiotherapy in the form of 46 Gy /23 fractions /5 weeks to whole pelvis with concurrent cisplatin 40 mg/m 2 weekly. Phase II was 20 Gy /10 fractions /2 weeks to the bladder tumor with concurrent cisplatin 40 mg/m2 weekly. After phase I, patients who had complete response (CR) or partial response (PR) were subjected to phase II and patients who had stationary disease (SD) were subjected to salvage cystectomy. After the end of treatment, patients who had CR were subjected to bladder preservation. Radiological and cystoscopic reevaluation was done to assess the tumor response after phase I and phase II. After completion of the scheduled treatment, patients were under follow up for clinical examination, radiological, and cystoscopic assessment. Results: The treatment schedule was tolerable and was associated with infrequent incidence of moderate toxicity that was easily controlled without interruption of treatment. Bladder preservation was achieved in 72% of patients. The actuarial relapse free survival and overall survival at a median follow up 18 months for patients who were candidate for bladder preservation were 81% and 100%; respectively. Invasive recurrence (16%) sal-Jvaged with cystectomy and superficial recurrence (6%) successfully treated with Bacilles bilie de Calmette- Guerin. Conclusions: This study indicates that in spite of a relatively small number of patients and short follow-up period; the trimodality treatment could be an

  15. In patients with a tumour invading the phrenic nerve does prophylactic diaphragm plication improve postoperative lung function?

    Science.gov (United States)

    Beattie, Gwyn W; Dunn, William G; Asif, Mohammed

    2016-09-01

    A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was 'In patients with tumours involving the phrenic nerve, does prophylactic diaphragm plication improve lung function following tumour resection?' Using the reported search, 258 papers were found of which 6 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Three case reports and one case series represent 37 patients in the literature along with two relevant animal studies. Patients treated with prophylactic plication at the time of injury or sacrifice of the phrenic nerve had reduced radiological evidence of diaphragm paralysis, lower reported shortness of breath and reduced requirement for ventilatory support. In patients with prophylactic diaphragm plication and a concurrent pulmonary resection, the predicted postoperative lung function correlated closely with the postoperative measured FEV1, FVC and gas transfer. The postoperative measured FEV1 was reported as 86-98%, the FVC 82-89% and gas transfer 97% of the predicted values. Two animal models investigate the mechanics of respiration, spirometry and gas exchange following diaphragmatic plication. A randomized control study in four dogs measured a 50% reduction in tidal volume and respiratory rate, a 40% decrease in arterial PO2 and a 43% increase in arterial CO2 when the phrenic nerve was crushed in animals with a pneumonectomy but without prophylactic diaphragm plication. A further randomized control animal study with 28 dogs found that plicating the diaphragm after unilateral phrenic nerve transection resulted in a significant increase in tidal volume and lung compliance and a significant decrease in respiratory frequency and the work of breathing. Prophylactic diaphragm plication may preserve lung function, reduce the risk of

  16. Short QT syndrome

    Directory of Open Access Journals (Sweden)

    Fiorenzo Gaita

    2011-12-01

    Full Text Available The short QT syndrome (SQTS is a recently described genetic arrhythmogenic disorder, characterized by abnormally short QT intervals on surface electrocardiogram (ECG and a high incidence of sudden death (SD during life, including the first months of life. The inheritance of SQTS is autosomal dominant, with genetic heterogeneity. Gain-of-function mutations in 3 genes encoding potassium channels have been associated to the disease: KCNH2 encoding IKr (SQT1, KCNQ1 encoding IKs (SQT2, and KCNJ2 encoding IK1 (SQT3. Loss-of-function mutations in 3 genes encoding the cardiac L-type calcium channel, CACNA1C, CACNB2b and CACNA2D1 may underlie a mixed phenotype of Brugada pattern ECG (or non-specific repolarization changes in case of CACNA2D1 and shorter than normal QT intervals. Clinical presentation is often severe, as cardiac arrest represents the first clinical presentation in most subjects. Moreover, often a noticeable family history of cardiac SD is present. Atrial fibrillation may be observed, also in young individuals. At electrophysiological study, short atrial and ventricular refractory periods are found, and atrial and ventricular fibrillation are easily induced by programmed electrical stimulation. The outcome of patients with SQTS becomes relatively safe when they are identified and treated. Currently, the suggested therapeutic strategy is an implantable cardioverter- defibrillator (ICD in patients with personal history of aborted SD or syncope. In asymptomatic adult patients from highly symptomatic families and in newborn children pharmacological treatment with hydroquinidine, which has been shown to prolong the QT interval and reduce the inducibility of ventricular arrhythmias, may be proposed.

  17. Short bowel syndrome.

    LENUS (Irish Health Repository)

    Donohoe, Claire L

    2012-02-01

    The short bowel syndrome (SBS) is a state of malabsorption following intestinal resection where there is less than 200 cm of intestinal length. The management of short bowel syndrome can be challenging and is best managed by a specialised multidisciplinary team. A good understanding of the pathophysiological consequences of resection of different portions of the small intestine is necessary to anticipate and prevent, where possible, consequences of SBS. Nutrient absorption and fluid and electrolyte management in the initial stages are critical to stabilisation of the patient and to facilitate the process of adaptation. Pharmacological adjuncts to promote adaptation are in the early stages of development. Primary restoration of bowel continuity, if possible, is the principle mode of surgical treatment. Surgical procedures to increase the surface area of the small intestine or improve its function may be of benefit in experienced hands, particularly in the paediatric population. Intestinal transplant is indicated at present for patients who have failed to tolerate long-term parenteral nutrition but with increasing experience, there may be a potentially expanded role for its use in the future.

  18. Impacts of Woody Invader Dillenia suffruticosa (Griff. Martelli on Physio-chemical Properties of Soil and, Below and Above Ground Flora

    Directory of Open Access Journals (Sweden)

    B.A.K. Wickramathilake

    2014-01-01

    Full Text Available Dillenia suffruticosa (Griffith Martelli, that spreads fast in low-lying areas in wet zone of Sri Lanka is currently listed as a nationally important Invasive Alien Species that deserves attention in ecological studies. Thus, impact of this woody invader on physical, chemical properties of soil and below and above ground flora was investigated. Five sampling sites were identified along a distance of 46km from Avissawella to Ratnapura. At each site, two adjacent plots [1m x10m each for D. suffruticosa present (D+ and absent (D-] were outlined. Physical and chemical soil parameters, microbial biomass and number of bacterial colonies in soil were determined using standard procedures and compared between D+ and D- by ANOVA using SPSS. Rate of decomposition of D. suffruticosa leaves was also determined using the litter bag technique at 35% and 50% moisture levels. Above ground plant species richness in sample stands was compared using Jaccard and Sorenson diversity indices.  Decomposition of D. suffruticosa leaves was slow, but occurred at a more or less similar rate irrespective of moisture content of soil. Particle size distribution in D+ soil showed a much higher percentage of large soil particles.  Higher % porosity in D+ sites was a clear indication that the soil was aerated.  The pH was significantly lower for D+ than D- thus developing acidic soils whereas conductivity has been significantly high making soil further stressed. The significant drop in Cation Exchange Capacity (CEC in D+ soil was a remarkable finding to be concerned with as it correlated with fertility of soil. Significantly higher values of phosphates reported in D+ soil support the idea that plant invaders are capable to increase phosphates in soil. Higher biomass values recorded for D+ sites together with higher number of bacterial colonies could be related to the unexpectedly recorded higher Organic Carbon. Both  the  Jaccard  and  Sorenson   indices indicated  that

  19. Cell short circuit, preshort signature

    Science.gov (United States)

    Lurie, C.

    1980-01-01

    Short-circuit events observed in ground test simulations of DSCS-3 battery in-orbit operations are analyzed. Voltage signatures appearing in the data preceding the short-circuit event are evaluated. The ground test simulation is briefly described along with performance during reconditioning discharges. Results suggest that a characteristic signature develops prior to a shorting event.

  20. DNA marker-assisted evaluation of potato genotypes for potential resistance to potato cyst nematode pathotypes not yet invading into Japan.

    Science.gov (United States)

    Asano, Kenji; Kobayashi, Akira; Tsuda, Shogo; Nishinaka, Mio; Tamiya, Seiji

    2012-06-01

    One of major objectives of crop breeding is conferring resistance to diseases and pests. However, large-scale phenotypic evaluation for many diseases and pests is difficult because strict controls are required to prevent their spread. Detection of disease resistance genes by using DNA markers may be an alternative approach to select potentially resistant accessions. Potato (Solanum tuberosum L.) breeders in Japan extensively use resistance gene H1, which confers nearly absolute resistance to potato cyst nematode (Globodera rostochiensis) pathotype Ro1, the only pathotype found in Japan. However, considering the possibility of accidental introduction of the other pathotypes, breeding of resistant varieties is an important strategy to prevent infestation by non-invading pathotypes in Japan. In this study, to evaluate the prevalence of resistance genes in Japanese genetic resources, we developed a multiplex PCR method that simultaneously detects 3 resistance genes, H1, Gpa2 and Gro1-4. We revealed that many Japanese varieties possess not only H1 but Gpa2, which are potentially resistant to other pathotypes of potato cyst nematode. On the other hand, no genotype was found to have the Gro1-4, indicating importance of introduction of varieties having Gro1-4. Our results demonstrate the applicability of DNA-marker assisted evaluation of resistant potato genotypes without phenotypic evaluation.

  1. Predictions for an invaded world: A strategy to predict the distribution of native and non-indigenous species at multiple scales

    Science.gov (United States)

    Reusser, D.A.; Lee, H.

    2008-01-01

    Habitat models can be used to predict the distributions of marine and estuarine non-indigenous species (NIS) over several spatial scales. At an estuary scale, our goal is to predict the estuaries most likely to be invaded, but at a habitat scale, the goal is to predict the specific locations within an estuary that are most vulnerable to invasion. As an initial step in evaluating several habitat models, model performance for a suite of benthic species with reasonably well-known distributions on the Pacific coast of the US needs to be compared. We discuss the utility of non-parametric multiplicative regression (NPMR) for predicting habitat- and estuary-scale distributions of native and NIS. NPMR incorporates interactions among variables, allows qualitative and categorical variables, and utilizes data on absence as well as presence. Preliminary results indicate that NPMR generally performs well at both spatial scales and that distributions of NIS are predicted as well as those of native species. For most species, latitude was the single best predictor, although similar model performance could be obtained at both spatial scales with combinations of other habitat variables. Errors of commission were more frequent at a habitat scale, with omission and commission errors approximately equal at an estuary scale. ?? 2008 International Council for the Exploration of the Sea. Published by Oxford Journals. All rights reserved.

  2. An unusual and spectacular case of spindle cell lipoma of the posterior neck invading the spinal cervical canal and posterior cranial fossa.

    Science.gov (United States)

    Petit, Damien; Menei, Philippe; Fournier, Henri-Dominique

    2011-11-01

    The authors describe the first case of spindle cell lipoma of the posterior neck invading the upper cervical spinal canal and the posterior cranial fossa. Spindle cell lipoma is an extremely rare variant of benign lipoma. It usually occurs as a solitary subcutaneous well-circumscribed lesion in the posterior neck or shoulders of adult men. Local aggressiveness is unusual. This 61-year-old man presented with an increased left cerebellar syndrome and headaches. He also had a posterior neck tumefaction, which had been known about for a long time. Computed tomography and MR imaging studies revealed a voluminous mass extending to the upper cervical canal and posterior cranial fossa and eroding the neighboring bones. The lesion was well delimited, and contrast enhancement was intense and heterogeneous. The tumor, which had initially developed under the muscles of the posterior neck, was totally resected. Histological assessment revealed numerous fat cells with spindle cells secreting collagen. The large size of the tumor and the submuscular location, bone erosion, and compression of the CNS were unusual in this rare subtype of benign adipose tumor. Its presentation could simulate a sarcoma.

  3. Is mathematics invading human cells?

    DEFF Research Database (Denmark)

    Booss-Bavnbek, Bernhelm

    2013-01-01

    The author describes some of his experiences as a mathematician cooperating with diabetes specialists.......The author describes some of his experiences as a mathematician cooperating with diabetes specialists....

  4. Newnes short wave listening handbook

    CERN Document Server

    Pritchard, Joe

    2013-01-01

    Newnes Short Wave Listening Handbook is a guide for starting up in short wave listening (SWL). The book is comprised of 15 chapters that discuss the basics and fundamental concepts of short wave radio listening. The coverage of the text includes electrical principles; types of signals that can be heard in the radio spectrum; and using computers in SWL. The book also covers SWL equipment, such as receivers, converters, and circuits. The text will be of great use to individuals who want to get into short wave listening.

  5. Predicting incursion of plant invaders into Kruger National Park, South Africa: the interplay of general drivers and species-specific factors.

    Directory of Open Access Journals (Sweden)

    Vojtěch Jarošík

    Full Text Available BACKGROUND: Overcoming boundaries is crucial for incursion of alien plant species and their successful naturalization and invasion within protected areas. Previous work showed that in Kruger National Park, South Africa, this process can be quantified and that factors determining the incursion of invasive species can be identified and predicted confidently. Here we explore the similarity between determinants of incursions identified by the general model based on a multispecies assemblage, and those identified by species-specific models. We analyzed the presence and absence of six invasive plant species in 1.0×1.5 km segments along the border of the park as a function of environmental characteristics from outside and inside the KNP boundary, using two data-mining techniques: classification trees and random forests. PRINCIPAL FINDINGS: The occurrence of Ageratum houstonianum, Chromolaena odorata, Xanthium strumarium, Argemone ochroleuca, Opuntia stricta and Lantana camara can be reliably predicted based on landscape characteristics identified by the general multispecies model, namely water runoff from surrounding watersheds and road density in a 10 km radius. The presence of main rivers and species-specific combinations of vegetation types are reliable predictors from inside the park. CONCLUSIONS: The predictors from the outside and inside of the park are complementary, and are approximately equally reliable for explaining the presence/absence of current invaders; those from the inside are, however, more reliable for predicting future invasions. Landscape characteristics determined as crucial predictors from outside the KNP serve as guidelines for management to enact proactive interventions to manipulate landscape features near the KNP to prevent further incursions. Predictors from the inside the KNP can be used reliably to identify high-risk areas to improve the cost-effectiveness of management, to locate invasive plants and target them for

  6. Predicting Incursion of Plant Invaders into Kruger National Park, South Africa: The Interplay of General Drivers and Species-Specific Factors

    Science.gov (United States)

    Jarošík, Vojtěch; Pyšek, Petr; Foxcroft, Llewellyn C.; Richardson, David M.; Rouget, Mathieu; MacFadyen, Sandra

    2011-01-01

    Background Overcoming boundaries is crucial for incursion of alien plant species and their successful naturalization and invasion within protected areas. Previous work showed that in Kruger National Park, South Africa, this process can be quantified and that factors determining the incursion of invasive species can be identified and predicted confidently. Here we explore the similarity between determinants of incursions identified by the general model based on a multispecies assemblage, and those identified by species-specific models. We analyzed the presence and absence of six invasive plant species in 1.0×1.5 km segments along the border of the park as a function of environmental characteristics from outside and inside the KNP boundary, using two data-mining techniques: classification trees and random forests. Principal Findings The occurrence of Ageratum houstonianum, Chromolaena odorata, Xanthium strumarium, Argemone ochroleuca, Opuntia stricta and Lantana camara can be reliably predicted based on landscape characteristics identified by the general multispecies model, namely water runoff from surrounding watersheds and road density in a 10 km radius. The presence of main rivers and species-specific combinations of vegetation types are reliable predictors from inside the park. Conclusions The predictors from the outside and inside of the park are complementary, and are approximately equally reliable for explaining the presence/absence of current invaders; those from the inside are, however, more reliable for predicting future invasions. Landscape characteristics determined as crucial predictors from outside the KNP serve as guidelines for management to enact proactive interventions to manipulate landscape features near the KNP to prevent further incursions. Predictors from the inside the KNP can be used reliably to identify high-risk areas to improve the cost-effectiveness of management, to locate invasive plants and target them for eradication. PMID:22194893

  7. Especies del género Tamarix (Tamaricaceae invadiendo ambientes naturales y seminaturales en Argentina Tamarix species (Tamaricaceae invading natural and seminatural habitats in Argentina

    Directory of Open Access Journals (Sweden)

    E. S. Natale

    2008-07-01

    Full Text Available El género Tamarix incluye especies con antecedentes como invasores agresivos en ambientes naturales de Estados Unidos, México y Australia. Su presencia en Argentina es conocida desde hace mucho tiempo, cultivado como ornamental, cortina corta-vientos o para sombra o creciendo de manera espontánea. Estudios previos citan un número variable de especies del género como cultivadas en el país, este trabajo aclara confusiones relacionadas con sinonimias, confirmando la presencia de cuatro especies en el país: T. gallica, T. ramosissima, T. chinensis y T. parviflora, las tres primeras registradas colonizando ambientes naturales o seminaturales. Se describen las especies del género citadas para Argentina y se provee una clave para su identificación. Se presenta la distribución conocida hasta el momento del género y se incluyen mapas con la ubicación de poblaciones establecidas e invasoras de cada especie a nivel nacional.The genus Tamarix includes species behaving as aggressive invaders in the USA, México and Australia. Previous studies report a variable number of species of this genus cultivated in Argentina as ornamentals, wind-break or for shadow, or growing spontaneously. This work makes clear some confusion related to synonyms and confirms the presence of four species in our country: T. gallica, T. ramosissima, T. chinensis and T. parviflora, the former three recorded colonizing natural and semi-natural habitats. A description of these species is given, together with a key for their identification, and information of their geographical distribution in Argentina, including maps showing the occurrence of established and invasive populations.

  8. The production of antibody by invading B cells is required for the clearance of rabies virus from the central nervous system.

    Directory of Open Access Journals (Sweden)

    D Craig Hooper

    2009-10-01

    Full Text Available The pathogenesis of rabies is associated with the inability to deliver immune effectors across the blood-brain barrier and to clear virulent rabies virus from CNS tissues. However, the mechanisms that facilitate immune effector entry into CNS tissues are induced by infection with attenuated rabies virus.Infection of normal mice with attenuated rabies virus but not immunization with killed virus can promote the clearance of pathogenic rabies virus from the CNS. T cell activity in B cell-deficient mice can control the replication of attenuated virus in the CNS, but viral mRNA persists. Low levels of passively administered rabies virus-neutralizing antibody reach infected cells in the cerebellum of B cell-deficient mice but are not sufficient to mediate virus clearance. Production of rabies virus-specific antibody by B cells invading CNS tissues is required for this process, and a substantial proportion of the B cells that accumulate in the CNS of mice infected with attenuated rabies virus produce virus-specific antibodies.The mechanisms required for immune effectors to enter rabies virus-infected tissues are induced by infection with attenuated rabies virus but not by infection with pathogenic rabies viruses or immunization with killed virus. T cell activities can inhibit rabies virus replication, but the production of rabies virus-specific antibodies by infiltrating B cells, as opposed to the leakage of circulating antibody across the BBB, is critical to elimination of the virus. These findings suggest that a pathogenic rabies virus infection may be treatable after the virus has reached the CNS tissues, providing that the appropriate immune effectors can be targeted to the infected tissues.

  9. Benefits to rare plants and highway safety from annual population reductions of a "native invader," white-tailed deer, in a Chicago-area woodland.

    Science.gov (United States)

    Engeman, Richard M; Guerrant, Travis; Dunn, Glen; Beckerman, Scott F; Anchor, Chris

    2014-01-01

    Overabundant white-tailed deer are one of the most serious threats to woodland plant communities in the Chicago area. Moreover, the abundant deer in a highly populated area causes economic harm and poses hazards to human safety through collisions with vehicles. The artificial conditions causing the overabundance and resulting consequences qualify the white-tailed deer in the Chicago area to be considered as "native invaders". We examined the benefits of culling deer at a Chicago-area woodland preserve by comparing browse rates on four endangered plant species from years before culling began with years with culling. We also examined deer-vehicle collision and traffic flow rates on area roads from years before culling began and years with culling to assess whether population reductions may have benefited road safety in the area. All four endangered plant species (three orchid species and sweet fern) had lower browse rates in years with culls, although the decreased browsing rates were statistically distinguishable for only two of the species (grass pink orchid and sweet fern). After first verifying that traffic flow rates did not decrease from pre-cull years to years with culls, we analyzed the Illinois Department of Transportation data from area roads based on deer-vehicle collisions causing >US$500 in damage and showed a one-third reduction in deer-vehicle collisions. An economic analysis showed a cost savings during the cull years of US$0.6 million for reducing browsing to just these four monitored plant species and the reduction in deer-vehicle collisions.

  10. Trophic flexibility of the Atlantic blue crab Callinectes sapidus in invaded coastal systems of the Apulia region (SE Italy): A stable isotope analysis

    Science.gov (United States)

    Mancinelli, Giorgio; Teresa Guerra, Maria; Alujević, Karla; Raho, Davide; Zotti, Maurizio; Vizzini, Salvatrice

    2017-11-01

    The Atlantic blue crab Callinectes sapidus is recognized as an Invasive Alien Species in the Mediterranean Sea. However, its trophic role and feeding flexibility in invaded benthic food webs have been addressed only recently. Here, field samplings were conducted in winter and summer in five coastal systems of the Apulia region (SE Italy), three located on the Ionian Sea (Mar Piccolo, Torre Colimena, and Spunderati) and two on the Adriatic Sea (Acquatina and Alimini Grande). Captured blue crabs were weighed and had their δ13C and δ15N isotopic signatures measured; their trophic level (TL) was estimated using the mussel Mytilus galloprovincialis as isotopic baseline. C. sapidus abundances varied greatly across systems and seasons, and in Adriatic systems the species was not collected in winter. Trophic levels showed significant spatial and temporal variations, although with no general pattern. In winter, the Mar Piccolo population showed the highest TL values; the lowest estimates were in Torre Colimena and Spunderati, where crabs showed δ13C signatures significantly higher than mussels, suggesting the contribution of 13C-enriched plant material in the diet. In summer, with the exception of the Mar Piccolo, Ionian populations increased their trophic level; both Adriatic populations were characterized by the lowest TL estimates. The analysis performed at the individual scale further indicated body weight-related changes in trophic level. For the Torre Colimena population, in particular, a hump-shaped pattern was observed in both seasons. The present study highlighted a considerable spatial and temporal trophic flexibility of C. sapidus at the population scale, while at the individual scale size-related shifts in trophic level were observed. The ability of the blue crab to vary its energy sources in relation with season, local environmental conditions, and ontogenetic stage is emphasized, suggesting that it may represent a key determinant of its invasion success.

  11. The Gene tia, Harbored by the Subtilase-Encoding Pathogenicity Island, Is Involved in the Ability of Locus of Enterocyte Effacement-Negative Shiga Toxin-Producing Escherichia coli Strains To Invade Monolayers of Epithelial Cells

    Science.gov (United States)

    Chiani, Paola; Michelacci, Valeria; Minelli, Fabio; Caprioli, Alfredo; Morabito, Stefano

    2017-01-01

    ABSTRACT Locus of enterocyte effacement (LEE)-negative Shiga toxin (Stx)-producing Escherichia coli (STEC) strains are human pathogens that lack the LEE locus, a pathogenicity island (PAI) involved in the intimate adhesion of LEE-positive strains to the host gut epithelium. The mechanism used by LEE-negative STEC strains to colonize the host intestinal mucosa is still not clear. The cell invasion determinant tia, previously described in enterotoxigenic E. coli strains, has been identified in LEE-negative STEC strains that possess the subtilase-encoding pathogenicity island (SE-PAI). We evaluated the role of the gene tia, present in these LEE-negative STEC strains, in the invasion of monolayers of cultured cells. We observed that these strains were able to invade Caco-2 and HEp-2 cell monolayers and compared their invasion ability with that of a mutant strain in which the gene tia had been inactivated. Mutation of the gene tia resulted in a strong reduction of the invasive phenotype, and complementation of the tia mutation with a functional copy of the gene restored the invasion activity. Moreover, we show that the gene tia is overexpressed in bacteria actively invading cell monolayers, demonstrating that tia is involved in the ability to invade cultured monolayers of epithelial cells shown by SE-PAI-positive E. coli, including STEC, strains. However, the expression of the tia gene in the E. coli K-12 strain JM109 was not sufficient, in its own right, to confer to this strain the ability to invade cell monolayers, suggesting that at least another factor must be involved in the invasion ability displayed by the SE-PAI-positive strains. PMID:28893912

  12. The Gene tia, Harbored by the Subtilase-Encoding Pathogenicity Island, Is Involved in the Ability of Locus of Enterocyte Effacement-Negative Shiga Toxin-Producing Escherichia coli Strains To Invade Monolayers of Epithelial Cells.

    Science.gov (United States)

    Bondì, Roslen; Chiani, Paola; Michelacci, Valeria; Minelli, Fabio; Caprioli, Alfredo; Morabito, Stefano

    2017-12-01

    Locus of enterocyte effacement (LEE)-negative Shiga toxin (Stx)-producing Escherichia coli (STEC) strains are human pathogens that lack the LEE locus, a pathogenicity island (PAI) involved in the intimate adhesion of LEE-positive strains to the host gut epithelium. The mechanism used by LEE-negative STEC strains to colonize the host intestinal mucosa is still not clear. The cell invasion determinant tia , previously described in enterotoxigenic E. coli strains, has been identified in LEE-negative STEC strains that possess the subtilase-encoding pathogenicity island (SE-PAI). We evaluated the role of the gene tia , present in these LEE-negative STEC strains, in the invasion of monolayers of cultured cells. We observed that these strains were able to invade Caco-2 and HEp-2 cell monolayers and compared their invasion ability with that of a mutant strain in which the gene tia had been inactivated. Mutation of the gene tia resulted in a strong reduction of the invasive phenotype, and complementation of the tia mutation with a functional copy of the gene restored the invasion activity. Moreover, we show that the gene tia is overexpressed in bacteria actively invading cell monolayers, demonstrating that tia is involved in the ability to invade cultured monolayers of epithelial cells shown by SE-PAI-positive E. coli , including STEC, strains. However, the expression of the tia gene in the E. coli K-12 strain JM109 was not sufficient, in its own right, to confer to this strain the ability to invade cell monolayers, suggesting that at least another factor must be involved in the invasion ability displayed by the SE-PAI-positive strains. Copyright © 2017 American Society for Microbiology.

  13. Short-circuit impedance measurement

    DEFF Research Database (Denmark)

    Pedersen, Knud Ole Helgesen; Nielsen, Arne Hejde; Poulsen, Niels Kjølstad

    2003-01-01

    Methods for estimating the short-circuit impedance in the power grid are investigated for various voltage levels and situations. The short-circuit impedance is measured, preferably from naturally occurring load changes in the grid, and it is shown that such a measurement system faces different...

  14. Function and Regulation of Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR / CRISPR Associated (Cas Systems

    Directory of Open Access Journals (Sweden)

    Peter C. Fineran

    2012-10-01

    Full Text Available Phages are the most abundant biological entities on earth and pose a constant challenge to their bacterial hosts. Thus, bacteria have evolved numerous ‘innate’ mechanisms of defense against phage, such as abortive infection or restriction/modification systems. In contrast, the clustered regularly interspaced short palindromic repeats (CRISPR systems provide acquired, yet heritable, sequence-specific ‘adaptive’ immunity against phage and other horizontally-acquired elements, such as plasmids. Resistance is acquired following viral infection or plasmid uptake when a short sequence of the foreign genome is added to the CRISPR array. CRISPRs are then transcribed and processed, generally by CRISPR associated (Cas proteins, into short interfering RNAs (crRNAs, which form part of a ribonucleoprotein complex. This complex guides the crRNA to the complementary invading nucleic acid and targets this for degradation. Recently, there have been rapid advances in our understanding of CRISPR/Cas systems. In this review, we will present the current model(s of the molecular events involved in both the acquisition of immunity and interference stages and will also address recent progress in our knowledge of the regulation of CRISPR/Cas systems.

  15. Function and regulation of clustered regularly interspaced short palindromic repeats (CRISPR) / CRISPR associated (Cas) systems.

    Science.gov (United States)

    Richter, Corinna; Chang, James T; Fineran, Peter C

    2012-10-19

    Phages are the most abundant biological entities on earth and pose a constant challenge to their bacterial hosts. Thus, bacteria have evolved numerous 'innate' mechanisms of defense against phage, such as abortive infection or restriction/modification systems. In contrast, the clustered regularly interspaced short palindromic repeats (CRISPR) systems provide acquired, yet heritable, sequence-specific 'adaptive' immunity against phage and other horizontally-acquired elements, such as plasmids. Resistance is acquired following viral infection or plasmid uptake when a short sequence of the foreign genome is added to the CRISPR array. CRISPRs are then transcribed and processed, generally by CRISPR associated (Cas) proteins, into short interfering RNAs (crRNAs), which form part of a ribonucleoprotein complex. This complex guides the crRNA to the complementary invading nucleic acid and targets this for degradation. Recently, there have been rapid advances in our understanding of CRISPR/Cas systems. In this review, we will present the current model(s) of the molecular events involved in both the acquisition of immunity and interference stages and will also address recent progress in our knowledge of the regulation of CRISPR/Cas systems.

  16. Superconducting cyclotron magnet coil short

    International Nuclear Information System (INIS)

    Mallory, M.L.; Blosser, H.G.; Clark, D.J.; Launer, H.; Lawton, D.; Miller, P.; Resmini, F.

    1982-01-01

    In February 1981, a short circuit appeared in the superconducting coil of the K500 cyclotron. The short is resistive in character and therefore has no effect on steady state operation of the magnet. The resistance of the short varies, sometimes being below threshold of detection as a heat load on the cooling system and sometimes being significant. The resistance under certain conditions shows approximately cyclic phenomena with time constants in the range of seconds and other approximately cyclic phenomena which correlate with gross operating parameters of the magnet (shifting current from one coil to another at high field and lowering and raising the liquid helium level). A number of diagnostic studies of the short have been made, using 1) an array of flux sensing loops to sense the magnetic effect of the short, 2) voltage comparisons between upper and lower sections of the coil, 3) comparisons of forces in the nine member coil support system and 4) the effect of the short on the thermal charactersitics of the coil. Insulation failure or a metal chip shorting out turns have been explored in some detail but a convincing determination of the exact cause of the short may never be available, (even the extreme step of unwinding the coil having a significant probability that an imperfection with the observed characteristics would pass unnoticed). Analysis of the characteristics of the short indicated that the most serious consequence would be failure of the coils mechanical support system in the event that the magnet was quickly discharged, as in a dump or quench. To deal with this hazard, the support system has been modified by installing solid supports which prevent the coil from moving by an amount sufficient to damage the support system. We have also reexamined the data and calculations used in the original coil design and have made some additional measurements of the properties of the materials (yield strength, friction coefficient, Young's modulus) used in the

  17. Simkin et al. 2016 PNAS data on herbaceous species richness and associated plot and covariate information

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset includes the geographic location (lat/lon) for 15,136 plots, as well as the herbaceous species richness, climate, soil pH, and other variables related...

  18. PNAS Plus: Origin of first cells at terrestrial, anoxic geothermal fields

    Science.gov (United States)

    Mulkidjanian, Armen Y.; Bychkov, Andrew Yu.; Dibrova, Daria V.; Galperin, Michael Y.; Koonin, Eugene V.

    2012-04-01

    All cells contain much more potassium, phosphate, and transition metals than modern (or reconstructed primeval) oceans, lakes, or rivers. Cells maintain ion gradients by using sophisticated, energy-dependent membrane enzymes (membrane pumps) that are embedded in elaborate ion-tight membranes. The first cells could possess neither ion-tight membranes nor membrane pumps, so the concentrations of small inorganic molecules and ions within protocells and in their environment would equilibrate. Hence, the ion composition of modern cells might reflect the inorganic ion composition of the habitats of protocells. We attempted to reconstruct the "hatcheries" of the first cells by combining geochemical analysis with phylogenomic scrutiny of the inorganic ion requirements of universal components of modern cells. These ubiquitous, and by inference primordial, proteins and functional systems show affinity to and functional requirement for K+, Zn2+, Mn2+, and phosphate. Thus, protocells must have evolved in habitats with a high K+/Na+ ratio and relatively high concentrations of Zn, Mn, and phosphorous compounds. Geochemical reconstruction shows that the ionic composition conducive to the origin of cells could not have existed in marine settings but is compatible with emissions of vapor-dominated zones of inland geothermal systems. Under the anoxic, CO2-dominated primordial atmosphere, the chemistry of basins at geothermal fields would resemble the internal milieu of modern cells. The precellular stages of evolution might have transpired in shallow ponds of condensed and cooled geothermal vapor that were lined with porous silicate minerals mixed with metal sulfides and enriched in K+, Zn2+, and phosphorous compounds.

  19. Shorts due to diagnostic leads

    International Nuclear Information System (INIS)

    Ellis, J.F.; Lubell, M.S.; Pillsbury, R.D.; Shen, S.S.; Thome, R.J.; Walstrom, P.L.

    1985-01-01

    The superconducting toroidal field coils that are being tested in the Large Coil Test Facility (LCTF) are heavily instrumented. General Electric coil, a lead wire of an internal sensor became shorted across an estimated three or four turns of the pancake winding. This short occurred during the final stages of the winding fabrication and was not accessible for repair. Resistance, voltage gradient, and transient voltage decay measurements were performed to characterize the short and the magnetic damping of the large steel bobbin and outer structural ring. The 32-gage wire causing the short was estimated to be about 10 cm long, with a resistance of 55 mΩ. As a safety measure, we decided to burn out the shorted wire at room temperature before installing the coil in LCTF. Tests were made to determine the energy needed to vaporize a small wire. Computer calculations indicated that within the voltage limits set for the coil, it was not feasible to burn out the wire by rapidly dumping the coil from a low-current dc charge-up. We accomplished the burnout by applying 800 V at 3.25 A, and 60 Hz for about 1 s. Transient voltage decay measurements made after the burnout and compared with those made before the attempt confirmed that the short had indeed been opened

  20. The novel as short story

    Directory of Open Access Journals (Sweden)

    Kirk Schlueter

    2013-06-01

    Full Text Available In recent history, the novel has been thought of and defined primarily as a long prose narrative. However, this has not been the case historically, as the original meaning of "novel" was for "a piece of news" or "a short story or novella." Returning to this original definition, I propose a new way of viewing the work known contemporarily as the novel as a collection, or sequence, of united short stories rather than a single indivisible work, with the component short stories or novellas comprising the sequence renamed as "novels." A brief examination of several classic works traditionally considered novels serves to illustrate how this change in definition will affect reading.

  1. Infantile Short Bowel Syndrome: short and long term evaluation

    NARCIS (Netherlands)

    J.F. Olieman (Joanne)

    2009-01-01

    textabstractInfantile short bowel syndrome is a condition which is characterized by malabsorption of nutrients, as a result of congenital intestinal shortening or massive small bowel resection. Survival rates have improved over the years, but morbidity remains high and clinical management of these

  2. Short-range fundamental forces

    International Nuclear Information System (INIS)

    Antoniadis, I.; Baessler, S.; Buchner, M.; Fedorov, V.V.; Hoedl, S.; Nesvizhevsky, V.V.; Pignol, G.; Protasov, K.V.; Lambrecht, A.; Reynaud, S.; Sobolev, Y.

    2010-01-01

    We consider theoretical motivations to search for extra short-range fundamental forces as well as experiments constraining their parameters. The forces could be of two types: 1) spin-independent forces; 2) spin-dependent axion-like forces. Different experimental techniques are sensitive in respective ranges of characteristic distances. The techniques include measurements of gravity at short distances, searches for extra interactions on top of the Casimir force, precision atomic and neutron experiments. We focus on neutron constraints, thus the range of characteristic distances considered here corresponds to the range accessible for neutron experiments

  3. Sauria SINEs: Novel short interspersed retroposable elements that are widespread in reptile genomes.

    Science.gov (United States)

    Piskurek, Oliver; Austin, Christopher C; Okada, Norihiro

    2006-05-01

    SINEs are short interspersed retrotransposable elements that invade new genomic sites. Their retrotransposition depends on reverse transcriptase and endonuclease activities encoded by partner LINEs (long interspersed elements). Recent genomic research has demonstrated that retroposons account for at least 40% of the human genome. Hitherto, more than 30 families of SINEs have been characterized in mammalian genomes, comprising approximately 4600 extant species; the distribution and extent of SINEs in reptilian genomes, however, are poorly documented. With more than 7400 species of lizards and snakes, Squamata constitutes the largest and most diverse group of living reptiles. We have discovered and characterized a novel SINE family, Sauria SINEs, whose members are widely distributed among genomes of lizards, snakes, and tuataras. Sauria SINEs comprise a 5' tRNA-related region, a tRNA-unrelated region, and a 3' tail region (containing short tandem repeats) derived from LINEs. We distinguished eight Sauria SINE subfamilies in genomes of four major squamate lineages and investigated their evolutionary relationships. Our data illustrate the overall efficacy of Sauria SINEs as novel retrotransposable markers for elucidation of squamate evolutionary history. We show that all Sauria SINEs share an identical 3' sequence with Bov-B LINEs and propose that they utilize the enzymatic machinery of Bov-B LINEs for their own retrotransposition. This finding, along with the ubiquity of Bov-B LINEs previously demonstrated in squamate genomes, suggests that these LINEs have been an active partner of Sauria SINEs since this SINE family was generated more than 200 million years ago.

  4. Astronomical Spectroscopy A Short History

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 3; Issue 5. Astronomical Spectroscopy A Short History. J C Bhattacharyya. General Article Volume 3 Issue 5 May 1998 pp 24-29. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/003/05/0024-0029 ...

  5. A Short Term Analogue Memory

    DEFF Research Database (Denmark)

    Shah, Peter Jivan

    1992-01-01

    A short term analogue memory is described. It is based on a well-known sample-hold topology in which leakage currents have been minimized partly by circuit design and partly by layout techniques. Measurements on a test chip implemented in a standard 2.4 micron analogue CMOS process show a droop...

  6. Towards short wavelengths FELs workshop

    International Nuclear Information System (INIS)

    Ben-Zvi, I.; Winick, H.

    1993-01-01

    This workshop was caged because of the growing perception in the FEL source community that recent advances have made it possible to extend FEL operation to wavelengths about two orders of magnitude shorter than the 240 nm that has been achieved to date. In addition short wavelength FELs offer the possibilities of extremely high peak power (several gigawatts) and very short pulses (of the order of 100 fs). Several groups in the USA are developing plans for such short wavelength FEL facilities. However, reviewers of these plans have pointed out that it would be highly desirable to first carry out proof-of-principle experiments at longer wavelengths to increase confidence that the shorter wavelength devices will indeed perform as calculated. The need for such experiments has now been broadly accepted by the FEL community. Such experiments were the main focus of this workshop as described in the following objectives distributed to attendees: (1) Define measurements needed to gain confidence that short wavelength FELs will perform as calculated. (2) List possible hardware that could be used to carry out these measurements in the near term. (3) Define a prioritized FEL physics experimental program and suggested timetable. (4) Form collaborative teams to carry out this program

  7. SHORT COMMUNICATIONS, NOTES AND REPORTS

    African Journals Online (AJOL)

    Campbell Murn

    1976). Among raptors there are those species where only the female incubates, those where the male may also incubate for short to longer periods, and those in which females and males equally share the incubation (Newton 1979). It is well known that both sexes incubate the clutch in vultures, both in the wild (Mundy et al.

  8. Towards short wavelengths FELs workshop

    Science.gov (United States)

    Ben-Zvi, I.; Winick, H.

    1993-11-01

    This workshop was caged because of the growing perception in the FEL source community that recent advances have made it possible to extend FEL operation to wavelengths about two orders of magnitude shorter than the 240 nm that has been achieved to date. In addition short wavelength FEL's offer the possibilities of extremely high peak power (several gigawatts) and very short pulses (of the order of 100 fs). Several groups in the USA are developing plans for such short wavelength FEL facilities. However, reviewers of these plans have pointed out that it would be highly desirable to first carry out proof-of-principle experiments at longer wavelengths to increase confidence that the shorter wavelength devices will indeed perform as calculated. The need for such experiments has now been broadly accepted by the FEL community. Such experiments were the main focus of this workshop as described in the following objectives distributed to attendees: (1) Define measurements needed to gain confidence that short wavelength FEL's will perform as calculated. (2) List possible hardware that could be used to carry out these measurements in the near term. (3) Define a prioritized FEL physics experimental program and suggested timetable. (4) Form collaborative teams to carry out this program.

  9. Short-term flow induced crystallization in isotactic polypropylene : how short is short?

    NARCIS (Netherlands)

    Ma, Z.; Balzano, L.; Portale, G.; Peters, G.W.M.

    2013-01-01

    The so-called "short-term flow" protocol is widely applied in experimental flow-induced crystallization studies on polymers in order to separate the nucleation and subsequent growth processes [Liedauer et al. Int. Polym. Proc. 1993, 8, 236–244]. The basis of this protocol is the assumption that

  10. Complexity a very short introduction

    CERN Document Server

    Holland, John H

    2014-01-01

    The importance of complexity is well-captured by Hawking's comment: "Complexity is the science of the 21st century". From the movement of flocks of birds to the Internet, environmental sustainability, and market regulation, the study and understanding of complex non-linear systems has become highly influential over the last 30 years. In this Very Short Introduction, one of the leading figures in the field, John Holland, introduces the key elements and conceptual framework of complexity. From complex physical systems such as fluid flow and the difficulties of predicting weather, to complex adaptive systems such as the highly diverse and interdependent ecosystems of rainforests, he combines simple, well-known examples - Adam Smith's pin factory, Darwin's comet orchid, and Simon's 'watchmaker' - with an account of the approaches, involving agents and urn models, taken by complexity theory. ABOUT THE SERIES: The Very Short Introductions series from Oxford University Press contains hundreds of titles in almost eve...

  11. Review of short wavelength lasers

    International Nuclear Information System (INIS)

    Hagelstein, P.L.

    1985-01-01

    There has recently been a substantial amount of research devoted to the development of short wavelength amplifiers and lasers. A number of experimental results have been published wherein the observation of significant gain has been claimed on transitions in the EUV and soft x-ray regimes. The present review is intended to discuss the main approaches to the creation of population inversions and laser media in the short wavelength regime, and hopefully aid workers in the field by helping to provide access to a growing literature. The approaches to pumping EUV and soft x-ray lasers are discussed according to inversion mechanism. The approaches may be divided into roughly seven categories, including collisional excitation pumping, recombination pumping, direct photoionization and photoexcitation pumping, metastable state storage plus optical pumping, charge exchange pumping, and finally, the extension of free electron laser techniques into the EUV and soft x-ray regimes. 250 references

  12. Optimal short-sighted rules

    Directory of Open Access Journals (Sweden)

    Sacha eBourgeois-Gironde

    2012-09-01

    Full Text Available The aim of this paper is to assess the relevance of methodological transfers from behavioral ecology to experimental economics with respect to the elicitation of intertemporal preferences. More precisely our discussion will stem from the analysis of Stephens and Anderson’s (2001 seminal article. In their study with blue jays they document that foraging behavior typically implements short sighted choice rules which are beneficial in the long-run. Such long term profitability of short-sighted behavior cannot be evidenced when using a self-control paradigm (one which contrasts in a binary way sooner smaller and later larger payoffs but becomes apparent when ecological patch-paradigms (replicating economic situations in which the main trade-off consists in staying on a food patch or leaving for another patch are implemented. We transfer this methodology in view of contrasting foraging strategies and self-control in human intertemporal choices.

  13. Review of short wavelength lasers

    Energy Technology Data Exchange (ETDEWEB)

    Hagelstein, P.L.

    1985-03-18

    There has recently been a substantial amount of research devoted to the development of short wavelength amplifiers and lasers. A number of experimental results have been published wherein the observation of significant gain has been claimed on transitions in the EUV and soft x-ray regimes. The present review is intended to discuss the main approaches to the creation of population inversions and laser media in the short wavelength regime, and hopefully aid workers in the field by helping to provide access to a growing literature. The approaches to pumping EUV and soft x-ray lasers are discussed according to inversion mechanism. The approaches may be divided into roughly seven categories, including collisional excitation pumping, recombination pumping, direct photoionization and photoexcitation pumping, metastable state storage plus optical pumping, charge exchange pumping, and finally, the extension of free electron laser techniques into the EUV and soft x-ray regimes. 250 references.

  14. Statistical inference a short course

    CERN Document Server

    Panik, Michael J

    2012-01-01

    A concise, easily accessible introduction to descriptive and inferential techniques Statistical Inference: A Short Course offers a concise presentation of the essentials of basic statistics for readers seeking to acquire a working knowledge of statistical concepts, measures, and procedures. The author conducts tests on the assumption of randomness and normality, provides nonparametric methods when parametric approaches might not work. The book also explores how to determine a confidence interval for a population median while also providing coverage of ratio estimation, randomness, and causal

  15. Short-range communication system

    Science.gov (United States)

    Alhorn, Dean C. (Inventor); Howard, David E. (Inventor); Smith, Dennis A. (Inventor)

    2012-01-01

    A short-range communication system includes an antenna, a transmitter, and a receiver. The antenna is an electrical conductor formed as a planar coil with rings thereof being uniformly spaced. The transmitter is spaced apart from the plane of the coil by a gap. An amplitude-modulated and asynchronous signal indicative of a data stream of known peak amplitude is transmitted into the gap. The receiver detects the coil's resonance and decodes same to recover the data stream.

  16. Short Stature Diagnosis and Referral

    Directory of Open Access Journals (Sweden)

    Mohamad Maghnie

    2018-01-01

    Full Text Available The “360° GH in Europe” meeting, which examined various aspects of GH diseases, was held in Lisbon, Portugal, in June 2016. The Merck KGaA (Germany funded meeting comprised three sessions entitled “Short Stature Diagnosis and Referral,” “Optimizing Patient Management,” and “Managing Transition.” Each session had three speaker presentations, followed by a discussion period, and is reported as a manuscript, authored by the speakers. The first session examined current processes of diagnosis and referral by endocrine specialists for pediatric patients with short stature. Requirements for referral vary widely, by country and by patient characteristics such as age. A balance must be made to ensure eligible patients get referred while healthcare systems are not over-burdened by excessive referrals. Late referral and diagnosis of non-GH deficiency conditions can result in increased morbidity and mortality. The consequent delays in making a diagnosis may compromise the effectiveness of GH treatment. Algorithms for growth monitoring and evaluation of skeletal disproportions can improve identification of non-GH deficiency conditions. Performance and validation of guidelines for diagnosis of GH deficiency have not been sufficiently tested. Provocative tests for investigation of GH deficiency remain equivocal, with insufficient information on variations due to patient characteristics, and cutoff values for definition differ not only by country but also by the assay used. When referring and diagnosing causes of short stature in pediatric patients, clinicians need to rely on many factors, but the most essential is clinical experience.

  17. Structural and functional characterization of an archaeal clustered regularly interspaced short palindromic repeat (CRISPR)-associated complex for antiviral defense (CASCADE).

    Science.gov (United States)

    Lintner, Nathanael G; Kerou, Melina; Brumfield, Susan K; Graham, Shirley; Liu, Huanting; Naismith, James H; Sdano, Matthew; Peng, Nan; She, Qunxin; Copié, Valérie; Young, Mark J; White, Malcolm F; Lawrence, C Martin

    2011-06-17

    In response to viral infection, many prokaryotes incorporate fragments of virus-derived DNA into loci called clustered regularly interspaced short palindromic repeats (CRISPRs). The loci are then transcribed, and the processed CRISPR transcripts are used to target invading viral DNA and RNA. The Escherichia coli "CRISPR-associated complex for antiviral defense" (CASCADE) is central in targeting invading DNA. Here we report the structural and functional characterization of an archaeal CASCADE (aCASCADE) from Sulfolobus solfataricus. Tagged Csa2 (Cas7) expressed in S. solfataricus co-purifies with Cas5a-, Cas6-, Csa5-, and Cas6-processed CRISPR-RNA (crRNA). Csa2, the dominant protein in aCASCADE, forms a stable complex with Cas5a. Transmission electron microscopy reveals a helical complex of variable length, perhaps due to substoichiometric amounts of other CASCADE components. A recombinant Csa2-Cas5a complex is sufficient to bind crRNA and complementary ssDNA. The structure of Csa2 reveals a crescent-shaped structure unexpectedly composed of a modified RNA-recognition motif and two additional domains present as insertions in the RNA-recognition motif. Conserved residues indicate potential crRNA- and target DNA-binding sites, and the H160A variant shows significantly reduced affinity for crRNA. We propose a general subunit architecture for CASCADE in other bacteria and Archaea.

  18. Relativity a very short introduction

    CERN Document Server

    Stannard, F Russell

    2008-01-01

    Relativity: A Very Short Introduction makes the theory of relativity understandable and accessible. 100 years ago, Einstein's theory of relativity shattered the world of physics. Our comforting Newtonian ideas of space and time were replaced by bizarre and counterintuitive conclusions: if you move at high speed, time slows down, space squashes up and you get heavier; travel fast enough and you could weigh as much as a jumbo jet, be squashed thinner than a CD without feeling a thing - and live forever. And that was just the special theory. With the general theory came even stranger ideas of curved space-time, which changed our understanding of gravity and the cosmos.

  19. Sound a very short introduction

    CERN Document Server

    Goldsmith, Mike

    2015-01-01

    Sound is integral to how we experience the world, in the form of noise as well as music. But what is sound? What is the physical basis of pitch and harmony? And how are sound waves exploited in musical instruments? Sound: A Very Short Introduction looks at the science of sound and the behaviour of sound waves with their different frequencies. It also explores sound in different contexts, covering the audible and inaudible, sound underground and underwater, acoustic and electronic sound, and hearing in humans and animals. It concludes with the problem of sound out of place—noise and its reduction.

  20. Nothing a very short introduction

    CERN Document Server

    Close, Frank

    2009-01-01

    What is 'nothing'? What remains when you take all the matter away? Can empty space - a void - exist? This Very Short Introduction explores the science and the history of the elusive void: from Aristotle who insisted that the vacuum was impossible, via the theories of Newton and Einstein, to our very latest discoveries and why they can tell us extraordinary things about the cosmos. Frank Close tells the story of how scientists have explored the elusive void, and the rich discoveries that they have made there. He takes the reader on a lively and accessible history through ancient ideas and cultural superstitions to the frontiers of current research

  1. Superconductivity a very short introduction

    CERN Document Server

    Blundell, Stephen

    2009-01-01

    Superconductivity is one of the most exciting areas of research in physics today. Outlining the history of its discovery, and the race to understand its many mysterious and counter-intuitive phenomena, this Very Short Introduction explains in accessible terms the theories that have been developed, and how they have influenced other areas of science, including the Higgs boson of particle physics and ideas about the early Universe. It is an engaging and informative accountof a fascinating scientific detective story, and an intelligible insight into some deep and beautiful ideas of physics

  2. Planets a very short introduction

    CERN Document Server

    Rothery, David A

    2010-01-01

    Planets: A Very Short Introduction demonstrates the excitement, uncertainties, and challenges faced by planetary scientists, and provides an overview of our Solar System and its origins, nature, and evolution. Terrestrial planets, giant planets, dwarf planets and various other objects such as satellites (moons), asteroids, trans-Neptunian objects, and exoplanets are discussed. Our knowledge about planets has advanced over the centuries, and has expanded at a rapidly growing rate in recent years. Controversial issues are outlined, such as What qualifies as a planet? What conditions are required for a planetary body to be potentially inhabited by life? Why does Pluto no longer have planet status? And Is there life on other planets?

  3. Galaxies a very short introduction

    CERN Document Server

    Gribbin, John

    2008-01-01

    Galaxies: A Very Short Introduction explores the building blocks of the Universe. Standing like islands in space, each is made up of many hundreds of millions of stars in which the chemical elements are made, around which planets form, and where on at least one of those planets intelligent life has emerged. Our own galaxy, the Milky Way, is just one of several hundred million other galaxies. Yet it was only in the 1920s that we realised that there is more to the Universe. Since then, many exciting discoveries have been made about our own galaxy and about those beyond.

  4. Radioactivity a very short introduction

    CERN Document Server

    Tuniz, Claudio

    2012-01-01

    Radioactivity: A Very Short Introduction explains radioactivity and discusses its fundamental role in nature. Radioactivity remains misunderstood and feared perhaps because nuclear radiation cannot be detected by human senses, and can undoubtedly do great harm if appropriate precautions are not taken. Radioactivity in the stars and in the Earth and its wide range of applications in biomedicine, science, industry, agriculture are described, as well as the mechanisms of nuclear fission and fusion, and the harnessing of nuclear power. The issues surrounding safety and security and the increasing concerns about nuclear terrorism are also considered.

  5. Short recovery time NMR probe

    International Nuclear Information System (INIS)

    Ramia, M.E.; Martin, C.A.; Jeandrevin, S.

    2011-01-01

    A NMR probe for low frequency and short recovery time is presented in this work. The probe contains the tuning circuit, diode expanders and quarter wavelength networks to protect the receiver from both the amplifier noise and the coil ringing following the transmitter power pulse. It also possesses a coil damper which is activated by of non active components. The probe performance shows a recovery time of about of 15μs a sensitive Q factor reduction and an increase of the signal to noise ratio of about 68% during the reception at a work frequency of 2 MHz. (author)

  6. Moons a very short introduction

    CERN Document Server

    Rothery, David A

    2015-01-01

    Moons: A Very Short Introduction introduces the reader to the varied and fascinating moons of our Solar System. Beginning with the early discoveries of Galileo and others, it describes their variety of mostly mythological names, and the early use of Jupiter’s moons to establish position at sea and to estimate the speed of light. It discusses the structure, formation, and profound influence of our Moon, those of the other planets, and ends with the recent discovery of moons orbiting asteroids, whilst looking forward to the possibility of discovering microbial life beyond Earth and of finding moons of exoplanets in planetary systems far beyond our own.

  7. Magnetism a very short introduction

    CERN Document Server

    Blundell, Stephen J

    2012-01-01

    Magnetism: A Very Short Introduction explains the mysteries and importance of magnetism. For centuries magnetism has been used for various exploits: as a great healer, a navigation aid through compasses, and through motors, generators, and turbines it has given us power. Our understanding of electricity and magnetism, from the work of Galvani, Ampère, Faraday, and Tesla is explored, and how Maxwell and Faraday's work led to the unification of electricity and magnetism is explained. With a discussion of the relationship between magnetism and relativity, quantum magnetism, and its impact on computers and information storage, how magnetism has changed our fundamental understanding of the Universe is shown.

  8. Short rotation Wood Crops Program

    Energy Technology Data Exchange (ETDEWEB)

    Wright, L.L.; Ehrenshaft, A.R.

    1990-08-01

    This report synthesizes the technical progress of research projects in the Short Rotation Woody Crops Program for the year ending September 30, 1989. The primary goal of this research program, sponsored by the US Department of Energy's Biofuels and Municipal Waste Technology Division, is the development of a viable technology for producing renewable feedstocks for conversion to biofuels. One of the more significant accomplishments was the documentation that short-rotation woody crops total delivered costs could be $40/Mg or less under optimistic but attainable conditions. By taking advantage of federal subsidies such as those offered under the Conservation Reserve Program, wood energy feedstock costs could be lower. Genetic improvement studies are broadening species performance within geographic regions and under less-than-optimum site conditions. Advances in physiological research are identifying key characteristics of species productivity and response to nutrient applications. Recent developments utilizing biotechnology have achieved success in cell and tissue culture, somaclonal variation, and gene-insertion studies. Productivity gains have been realized with advanced cultural studies of spacing, coppice, and mixed-species trials. 8 figs., 20 tabs.

  9. Isotopes a very short introduction

    CERN Document Server

    Ellam, Rob

    2016-01-01

    An isotope is a variant form of a chemical element, containing a different number of neutrons in its nucleus. Most elements exist as several isotopes. Many are stable while others are radioactive, and some may only exist fleetingly before decaying into other elements. In this Very Short Introduction, Rob Ellam explains how isotopes have proved enormously important across all the sciences and in archaeology. Radioactive isotopes may be familiar from their use in nuclear weapons, nuclear power, and in medicine, as well as in carbon dating. They have been central to establishing the age of the Earth and the origins of the solar system. Combining previous and new research, Ellam provides an overview of the nature of stable and radioactive isotopes, and considers their wide range of modern applications. ABOUT THE SERIES: The Very Short Introductions series from Oxford University Press contains hundreds of titles in almost every subject area. These pocket-sized books are the perfect way to get ahead in a new subjec...

  10. Expression profiling of migrated and invaded breast cancer cells predicts early metastatic relapse and reveals Krüppel-like factor 9 as a potential suppressor of invasive growth in breast cancer

    Science.gov (United States)

    Limame, Ridha; de Beeck, Ken Op; Van Laere, Steven; Croes, Lieselot; De Wilde, Annemieke; Dirix, Luc; Van Camp, Guy; Peeters, Marc; De Wever, Olivier; Lardon, Filip; Pauwels, Patrick

    2014-01-01

    Cell motility and invasion initiate metastasis. However, only a subpopulation of cancer cells within a tumor will ultimately become invasive. Due to this stochastic and transient nature, in an experimental setting, migrating and invading cells need to be isolated from the general population in order to study the gene expression profiles linked to these processes. This report describes microarray analysis on RNA derived from migrated or invaded subpopulations of triple negative breast cancer cells in a Transwell set-up, at two different time points during motility and invasion, pre-determined as “early” and “late” in real-time kinetic assessments. Invasion- and migration-related gene expression signatures were generated through comparison with non-invasive cells, remaining at the upper side of the Transwell membranes. Late-phase signatures of both invasion and migration indicated poor prognosis in a series of breast cancer data sets. Furthermore, evaluation of the genes constituting the prognostic invasion-related gene signature revealed Krüppel-like factor 9 (KLF9) as a putative suppressor of invasive growth in breast cancer. Next to loss in invasive vs non-invasive cell lines, KLF9 also showed significantly lower expression levels in the “early” invasive cell population, in several public expression data sets and in clinical breast cancer samples when compared to normal tissue. Overexpression of EGFP-KLF9 fusion protein significantly altered morphology and blocked invasion and growth of MDA-MB-231 cells in vitro. In addition, KLF9 expression correlated inversely with mitotic activity in clinical samples, indicating anti-proliferative effects. PMID:25593984

  11. Economic impact analysis of short line railroads.

    Science.gov (United States)

    2014-10-01

    This research project assesses the economic role and impact of short line railroads in the state of Louisiana. While relatively small in : scope, with 11 operators and approximately 500 miles of track, short line railroads play a significant role in ...

  12. Short Pulse Laser Applications Design

    International Nuclear Information System (INIS)

    Town, R.J.; Clark, D.S.; Kemp, A.J.; Lasinski, B.F.; Tabak, M.

    2008-01-01

    We are applying our recently developed, LDRD-funded computational simulation tool to optimize and develop applications of Fast Ignition (FI) for stockpile stewardship. This report summarizes the work performed during a one-year exploratory research LDRD to develop FI point designs for the National Ignition Facility (NIF). These results were sufficiently encouraging to propose successfully a strategic initiative LDRD to design and perform the definitive FI experiment on the NIF. Ignition experiments on the National Ignition Facility (NIF) will begin in 2010 using the central hot spot (CHS) approach, which relies on the simultaneous compression and ignition of a spherical fuel capsule. Unlike this approach, the fast ignition (FI) method separates fuel compression from the ignition phase. In the compression phase, a laser such as NIF is used to implode a shell either directly, or by x rays generated from the hohlraum wall, to form a compact dense (∼300 g/cm 3 ) fuel mass with an areal density of ∼3.0 g/cm 2 . To ignite such a fuel assembly requires depositing ∼20kJ into a ∼35 (micro)m spot delivered in a short time compared to the fuel disassembly time (∼20ps). This energy is delivered during the ignition phase by relativistic electrons generated by the interaction of an ultra-short high-intensity laser. The main advantages of FI over the CHS approach are higher gain, a lower ignition threshold, and a relaxation of the stringent symmetry requirements required by the CHS approach. There is worldwide interest in FI and its associated science. Major experimental facilities are being constructed which will enable 'proof of principle' tests of FI in integrated subignition experiments, most notably the OMEGA-EP facility at the University of Rochester's Laboratory of Laser Energetics and the FIREX facility at Osaka University in Japan. Also, scientists in the European Union have recently proposed the construction of a new FI facility, called HiPER, designed to

  13. Coulomb repulsion in short polypeptides.

    Science.gov (United States)

    Norouzy, Amir; Assaf, Khaleel I; Zhang, Shuai; Jacob, Maik H; Nau, Werner M

    2015-01-08

    Coulomb repulsion between like-charged side chains is presently viewed as a major force that impacts the biological activity of intrinsically disordered polypeptides (IDPs) by determining their spatial dimensions. We investigated short synthetic models of IDPs, purely composed of ionizable amino acid residues and therefore expected to display an extreme structural and dynamic response to pH variation. Two synergistic, custom-made, time-resolved fluorescence methods were applied in tandem to study the structure and dynamics of the acidic and basic hexapeptides Asp6, Glu6, Arg6, Lys6, and His6 between pH 1 and 12. (i) End-to-end distances were obtained from the short-distance Förster resonance energy transfer (sdFRET) from N-terminal 5-fluoro-l-tryptophan (FTrp) to C-terminal Dbo. (ii) End-to-end collision rates were obtained for the same peptides from the collision-induced fluorescence quenching (CIFQ) of Dbo by FTrp. Unexpectedly, the very high increase of charge density at elevated pH had no dynamical or conformational consequence in the anionic chains, neither in the absence nor in the presence of salt, in conflict with the common view and in partial conflict with accompanying molecular dynamics simulations. In contrast, the cationic peptides responded to ionization but with surprising patterns that mirrored the rich individual characteristics of each side chain type. The contrasting results had to be interpreted, by considering salt screening experiments, N-terminal acetylation, and simulations, in terms of an interplay of local dielectric constant and peptide-length dependent side chain charge-charge repulsion, side chain functional group solvation, N-terminal and side chain charge-charge repulsion, and side chain-side chain as well as side chain-backbone interactions. The common picture that emerged is that Coulomb repulsion between water-solvated side chains is efficiently quenched in short peptides as long as side chains are not in direct contact with each

  14. 46 CFR 15.725 - Sailing short.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Sailing short. 15.725 Section 15.725 Shipping COAST... Limitations and Qualifying Factors § 15.725 Sailing short. Whenever a vessel is deprived of the service of a... vessel is sufficiently manned for the voyage. A report of sailing short must be filed in writing with the...

  15. Copernicus a very short introduction

    CERN Document Server

    Gingerich, Owen

    2016-01-01

    Nicolaus Copernicus (1473–1543) was the astronomer whose shocking vision of a sun-centered universe turned out to be the essential blueprint for a physical understanding of celestial motions. Copernicus: A Very Short Introduction offers a fascinating portrayal of the man who launched the modern vision of the universe. It sets Copernicus in the context of a rapidly changing world, where the recent invention of printing with movable type not only made sources more readily available to him, but also fueled Martin Luther’s transformation of the religious landscape. Copernicus’s heliocentric revolution is revealed as an aesthetic achievement not dictated by observational “proofs,” but another new way of looking at the ancient cosmos.

  16. Infinity a very short introduction

    CERN Document Server

    Stewart, Ian

    2017-01-01

    Infinity is an intriguing topic, with connections to religion, philosophy, metaphysics, logic, and physics as well as mathematics. Its history goes back to ancient times, with especially important contributions from Euclid, Aristotle, Eudoxus, and Archimedes. The infinitely large (infinite) is intimately related to the infinitely small (infinitesimal). Cosmologists consider sweeping questions about whether space and time are infinite. Philosophers and mathematicians ranging from Zeno to Russell have posed numerous paradoxes about infinity and infinitesimals. Many vital areas of mathematics rest upon some version of infinity. The most obvious, and the first context in which major new techniques depended on formulating infinite processes, is calculus. But there are many others, for example Fourier analysis and fractals. In this Very Short Introduction, Ian Stewart discusses infinity in mathematics while also drawing in the various other aspects of infinity and explaining some of the major problems and insights ...

  17. Downlink Transmission of Short Packets

    DEFF Research Database (Denmark)

    Trillingsgaard, Kasper Fløe; Popovski, Petar

    2017-01-01

    Cellular wireless systems rely on frame-based transmissions. The frame design is conventionally based on heuristics, consisting of a frame header and a data part. The frame header contains control information that provides pointers to the messages within the data part. In this paper, we revisit...... the principles of frame design and show the impact of the new design in scenarios that feature short data packets, which are central to various 5G and Internet of Things applications. We~treat framing for downlink transmission in an AWGN broadcast channel with $K$ users, where the sizes of the messages....... This requires changes in the way control information is sent, and it requires that the users need to spend power decoding other messages, thereby increasing the average power consumption. We~show that the common heuristic design is only one point on a curve that represents the tradeoff between latency and power...

  18. Shapeable short circuit resistant capacitor

    Science.gov (United States)

    Taylor, Ralph S.; Myers, John D.; Baney, William J.

    2015-10-06

    A ceramic short circuit resistant capacitor that is bendable and/or shapeable to provide a multiple layer capacitor that is extremely compact and amenable to desirable geometries. The capacitor that exhibits a benign failure mode in which a multitude of discrete failure events result in a gradual loss of capacitance. Each event is a localized event in which localized heating causes an adjacent portion of one or both of the electrodes to vaporize, physically cleaning away electrode material from the failure site. A first metal electrode, a second metal electrode, and a ceramic dielectric layer between the electrodes are thin enough to be formed in a serpentine-arrangement with gaps between the first electrode and the second electrode that allow venting of vaporized electrode material in the event of a benign failure.

  19. Astrophysics a very short introduction

    CERN Document Server

    Binney, James

    2016-01-01

    Astrophysics is the physics of the stars, and more widely the physics of the Universe. It enables us to understand the structure and evolution of planetary systems, stars, galaxies, interstellar gas, and the cosmos as a whole. In this Very Short Introduction, the leading astrophysicist James Binney shows how the field of astrophysics has expanded rapidly in the past century, with vast quantities of data gathered by telescopes exploiting all parts of the electromagnetic spectrum, combined with the rapid advance of computing power, which has allowed increasingly effective mathematical modelling. He illustrates how the application of fundamental principles of physics - the consideration of energy and mass, and momentum - and the two pillars of relativity and quantum mechanics, has provided insights into phenomena ranging from rapidly spinning millisecond pulsars to the collision of giant spiral galaxies. This is a clear, rigorous introduction to astrophysics for those keen to cut their teeth on a conceptual trea...

  20. Short Course in the Microbiome

    Directory of Open Access Journals (Sweden)

    Kimberly Falana

    2015-07-01

    Full Text Available Over the past decade, it has become evident that the microbiome is an important environmental factor that affects many physiological processes, such as cell proliferation and differentiation, behaviour, immune function and metabolism. More importantly, it may contribute to a wide variety of diseases, including cancer, inflammatory diseases, metabolic diseases and responses to pathogens. We expect that international, integrative and interdisciplinary translational research teams, along with the emergence of FDA-approved platforms, will set the framework for microbiome-based therapeutics and diagnostics. We recognize that the microbiome ecosystem offers new promise for personalized/precision medicine and targeted treatment for a variety of diseases. The short course was held as a four-session webinar series in April 2015, taught by pioneers and experts in the microbiome ecosystem, covering a broad range of topics from the healthy microbiome to the effects of an altered microbiome from neonates to adults and the long term effects as it is related to disease, from asthma to cancer. We have learned to appreciate how beneficial our microbes are in breaking down our food, fighting off infections and nurturing our immune system, and this information provides us with ideas as to how we can manipulate our microbiome to prevent certain diseases. However, given the variety of applications, there are scientific challenges, though there are very promising areas in reference to the clinical benefits of understanding more about our microbiome, whether in our gut or on our skin: the outlook is bright. A summary of the short course is presented as a meeting dispatch.

  1. TECHNICAL AND PRACTICAL IMPLICATIONS OF SHORT SELLING

    Directory of Open Access Journals (Sweden)

    Radu BORES

    2016-07-01

    Full Text Available This paper aims at providing insight into some of the implication of short selling for markets, investors as well as regulators. Findings show that capital flows are adversely affected by strict regulation and bans of short sales, while market liquidity, and bid-ask spread can be improved by allowing short selling. Additionally portfolios that incorporate short selling strategies can have lower volatility in returns. The informational content of short sales can provide important feedback for informed investors and lead to better price discovery.

  2. Intestino Corto Short bowel syndrome

    Directory of Open Access Journals (Sweden)

    María Matilde Socarrás Suárez

    2004-06-01

    Full Text Available El intestino corto está asociado a pérdida o disfunción del intestino delgado por resección del mismo, que causa diarreas, tránsito intestinal acelerado, malabsorción intestinal, y eventualmente la pérdida de peso y el desgaste muscular. El objetivo de este trabajo fue actualizar el conocimiento acerca de este síndrome. Se realiza una revisión del tema de intestino corto donde se refiere a su definición, causas fundamentales frecuentes e infrecuentes en el niño y en el adulto, cómo se adapta el intestino a la resección de diferentes extensiones, las funciones del íleon terminal. Se hacen una valoración clínica inicial, con el interrogatorio médico, revisión minuciosa de la historia clínica para cuantificar la capacidad de absorción. Se habla de los síntomas y signos de deficiencia nutricional. Se explican las estrategias del tratamiento, que tienen 3 etapas de evolución clínica. Se concluye que se indica la dietoterapia adecuada según el estado nutricional del paciente y la resección intestinal realizada, evitando las complicaciones para lograr una calidad máxima de vidaShort bowel is associated with loss or dysfunction of the small bowel due to its resection, which causes diarrheas, accelerated intestinal transit, intestinal malabsorption and, eventually, weight loss ansd muscular waste. The objective of this paper was to update knowledge about this syndrome. A review of the short intestine topic is made, making reference to its definition, common and uncommon main cuases in the child and adult, how the bowel adapts itslef to resection of different extensions, and the functions of the terminal ileum. An initial clinical assessment is made with the medical questionnaire and a detailed review of the medical history to quantify the absorption capacity. The symptoms and signs of nutritional deficiency are dealt with. The strategies of the treatment consisting of 3 stages of clinical evolution are explained. It is concluded

  3. A short environmental report on 'De Las Gallinas island'

    International Nuclear Information System (INIS)

    Romero, Claudio; Gho, Carlos J.; Quiroga, Juan J.; De Nicola, Juan; Rico, Nestor; Isnardi, Edgardo; Malagamba, Eduardo

    2003-01-01

    of pastures and the very scarce presence of exotic invading weeds. The main results of this work are: The island shows an enormous potential in terms of conservation, with a particular structure of almost no anthropic intervention. Facing the lack of updated scientific studies on the island, as a first step it would be recommendable to make a systematic characterization of its area, allowing a detailed knowledge of its ecological issues. This task should be done prior to any decision on its way of management, so preventing any ecological impact. This area might be seen as a preferential site to perform studies on vegetation dynamics in the absence of major herbivores. De Las Gallinas might also be transformed in an excellent work field for the many undergraduate and graduate thesis of the Superior School of Biology, at the Regional University Center of Bariloche. A synergic association of the City of Bariloche and the University of Comahue should be foreseen. In the short term, a limited program of eradication of the few exotic species occurring at the island should be tackled. Moreover, the activities of underwater swimming should be moved to the Huemul Island, which is clearly more heavily anthropized. Last but not least, an emphatic recommendation is made to keep its present character of protected untouchable area, in order to preserve its present condition and its natural assets. (author)

  4. Onboard Short Term Plan Viewer

    Science.gov (United States)

    Hall, Tim; LeBlanc, Troy; Ulman, Brian; McDonald, Aaron; Gramm, Paul; Chang, Li-Min; Keerthi, Suman; Kivlovitz, Dov; Hadlock, Jason

    2011-01-01

    Onboard Short Term Plan Viewer (OSTPV) is a computer program for electronic display of mission plans and timelines, both aboard the International Space Station (ISS) and in ISS ground control stations located in several countries. OSTPV was specifically designed both (1) for use within the limited ISS computing environment and (2) to be compatible with computers used in ground control stations. OSTPV supplants a prior system in which, aboard the ISS, timelines were printed on paper and incorporated into files that also contained other paper documents. Hence, the introduction of OSTPV has both reduced the consumption of resources and saved time in updating plans and timelines. OSTPV accepts, as input, the mission timeline output of a legacy, print-oriented, UNIX-based program called "Consolidated Planning System" and converts the timeline information for display in an interactive, dynamic, Windows Web-based graphical user interface that is used by both the ISS crew and ground control teams in real time. OSTPV enables the ISS crew to electronically indicate execution of timeline steps, launch electronic procedures, and efficiently report to ground control teams on the statuses of ISS activities, all by use of laptop computers aboard the ISS.

  5. Gravity a very short introduction

    CERN Document Server

    Clifton, Timothy

    2017-01-01

    Gravity is one of the four fundamental interactions that exist in nature. It also has the distinction of being the oldest, weakest, and most difficult force to quantize. Understanding gravity is not only essential for understanding the motion of objects on Earth, but also the motion of all celestial objects, and even the expansion of the Universe itself. It was the study of gravity that led Einstein to his profound realizations about the nature of space and time. Gravity is not only universal, it is also essential for understanding the behavior of the Universe, and all astrophysical bodies within it. In this Very Short Introduction Timothy Clifton looks at the development of our understanding of gravity since the early observations of Kepler and Newtonian theory. He discusses Einstein's theory of gravity, which now supplants Newton's, showing how it allows us to understand why the frequency of light changes as it passes through a gravitational field, why GPS satellites need their clocks corrected as they orbi...

  6. Light a very short introduction

    CERN Document Server

    Walmsley, Ian

    2015-01-01

    Light enables us to see the world around us. Our sense of sight provides us with direct information about space and time, the physical arrangement of the world, and how it changes. This almost universal shared sensation of vision has led to a fascination with the nature and properties of light across the ages. But the light we see is just a small part of the whole spectrum of electromagnetic radiation, ranging from radio waves to gamma rays. In this Very Short Introduction Ian Walmsley discusses early attempts to explain light, and the development of apparently opposing particulate and wave theories by scientists such as Isaac Newton and Christiaan Huygens. He shows how light was recognized as an electromagnetic wave in the 19th century, and the development of the quantum mechanics view of wave-particle duality in the 20th century. He also describes the many applications of light, domestic and scientific, such as microwaves, DVDs, and lasers. We now use the whole range of electromagnetic radiation to peer bot...

  7. A short history of insecticides

    Directory of Open Access Journals (Sweden)

    Oberemok Volodymyr Volodymyrovych

    2015-07-01

    Full Text Available This review contains a brief history of the use of insecticides. The peculiarities, main advantages, and disadvantages of some modern insecticides are described. The names of the discoverers of some of the most popular insecticide preparations on the world market, are listed. The tendencies to find new insecticides to control the quantity of phytophagous insects are discussed. Special attention is paid to the perspective of creating preparations based on nucleic acids, in particular DNA insecticides. The use of insect-specific, short single-stranded DNA fragments as DNA insecticides, is paving the way in the field of “intellectual” insecticides that “think” before they act. It is worth noting, though, that in the near future, the quantity of produced insecticides will increase due to the challenges associated with food production for a rapidly growing population. It is concluded, that an agreeable interaction of scientists and manufacturers of insecticides should lead to the selection of the most optimal solutions for insect pest control, which would be safe, affordable, and effective at the same time.

  8. Short- circuit tests of circuit breakers

    OpenAIRE

    Chorovský, P.

    2015-01-01

    This paper deals with short-circuit tests of low voltage electrical devices. In the first part of this paper, there are described basic types of short- circuit tests and their principles. Direct and indirect (synthetic) tests with more details are described in the second part. Each test and principles are explained separately. Oscilogram is obtained from short-circuit tests of circuit breakers at laboratory. The aim of this research work is to propose a test circuit for performing indirect test.

  9. Short-Selling, Leverage and Systemic Risk

    OpenAIRE

    Pais, Amelia; Stork, Philip A.

    2013-01-01

    During the Global Financial Crisis, regulators imposed short-selling bans to protect financial institutions. The rationale behind the bans was that “bear raids”, driven by short-sellers, would increase the individual and systemic risk of financial institutions, especially for institutions with high leverage. This study uses Extreme Value Theory to estimate the effect of short-selling on financial institutions’ individual and systemic risks in France, Italy and Spain; it also analyses the rela...

  10. A complex of Cas proteins 5, 6, and 7 is required for the biogenesis and stability of clustered regularly interspaced short palindromic repeats (crispr)-derived rnas (crrnas) in Haloferax volcanii.

    Science.gov (United States)

    Brendel, Jutta; Stoll, Britta; Lange, Sita J; Sharma, Kundan; Lenz, Christof; Stachler, Aris-Edda; Maier, Lisa-Katharina; Richter, Hagen; Nickel, Lisa; Schmitz, Ruth A; Randau, Lennart; Allers, Thorsten; Urlaub, Henning; Backofen, Rolf; Marchfelder, Anita

    2014-03-07

    The clustered regularly interspaced short palindromic repeats/CRISPR-associated (CRISPR-Cas) system is a prokaryotic defense mechanism against foreign genetic elements. A plethora of CRISPR-Cas versions exist, with more than 40 different Cas protein families and several different molecular approaches to fight the invading DNA. One of the key players in the system is the CRISPR-derived RNA (crRNA), which directs the invader-degrading Cas protein complex to the invader. The CRISPR-Cas types I and III use the Cas6 protein to generate mature crRNAs. Here, we show that the Cas6 protein is necessary for crRNA production but that additional Cas proteins that form a CRISPR-associated complex for antiviral defense (Cascade)-like complex are needed for crRNA stability in the CRISPR-Cas type I-B system in Haloferax volcanii in vivo. Deletion of the cas6 gene results in the loss of mature crRNAs and interference. However, cells that have the complete cas gene cluster (cas1-8b) removed and are transformed with the cas6 gene are not able to produce and stably maintain mature crRNAs. crRNA production and stability is rescued only if cas5, -6, and -7 are present. Mutational analysis of the cas6 gene reveals three amino acids (His-41, Gly-256, and Gly-258) that are essential for pre-crRNA cleavage, whereas the mutation of two amino acids (Ser-115 and Ser-224) leads to an increase of crRNA amounts. This is the first systematic in vivo analysis of Cas6 protein variants. In addition, we show that the H. volcanii I-B system contains a Cascade-like complex with a Cas7, Cas5, and Cas6 core that protects the crRNA.

  11. A Complex of Cas Proteins 5, 6, and 7 Is Required for the Biogenesis and Stability of Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-derived RNAs (crRNAs) in Haloferax volcanii*

    Science.gov (United States)

    Brendel, Jutta; Stoll, Britta; Lange, Sita J.; Sharma, Kundan; Lenz, Christof; Stachler, Aris-Edda; Maier, Lisa-Katharina; Richter, Hagen; Nickel, Lisa; Schmitz, Ruth A.; Randau, Lennart; Allers, Thorsten; Urlaub, Henning; Backofen, Rolf; Marchfelder, Anita

    2014-01-01

    The clustered regularly interspaced short palindromic repeats/CRISPR-associated (CRISPR-Cas) system is a prokaryotic defense mechanism against foreign genetic elements. A plethora of CRISPR-Cas versions exist, with more than 40 different Cas protein families and several different molecular approaches to fight the invading DNA. One of the key players in the system is the CRISPR-derived RNA (crRNA), which directs the invader-degrading Cas protein complex to the invader. The CRISPR-Cas types I and III use the Cas6 protein to generate mature crRNAs. Here, we show that the Cas6 protein is necessary for crRNA production but that additional Cas proteins that form a CRISPR-associated complex for antiviral defense (Cascade)-like complex are needed for crRNA stability in the CRISPR-Cas type I-B system in Haloferax volcanii in vivo. Deletion of the cas6 gene results in the loss of mature crRNAs and interference. However, cells that have the complete cas gene cluster (cas1–8b) removed and are transformed with the cas6 gene are not able to produce and stably maintain mature crRNAs. crRNA production and stability is rescued only if cas5, -6, and -7 are present. Mutational analysis of the cas6 gene reveals three amino acids (His-41, Gly-256, and Gly-258) that are essential for pre-crRNA cleavage, whereas the mutation of two amino acids (Ser-115 and Ser-224) leads to an increase of crRNA amounts. This is the first systematic in vivo analysis of Cas6 protein variants. In addition, we show that the H. volcanii I-B system contains a Cascade-like complex with a Cas7, Cas5, and Cas6 core that protects the crRNA. PMID:24459147

  12. Chaos: A Very Short Introduction

    Energy Technology Data Exchange (ETDEWEB)

    Klages, R [School of Mathematical Sciences, Mile End Road, London, E1 4NS (United Kingdom)

    2007-07-20

    field. I feel that occasionally the book is also getting a bit too intricate for the complete layman, and experts may not agree on all details of the more conceptual discussions. Altogether I thoroughly enjoyed reading this book. It was a happy companion while travelling and a nice bedtime literature. It is furthermore an excellent reminder of the 'big picture' underlying nonlinear science as it applies to the real world. I will gladly recommend this book as background literature for students in my introductory course on dynamical systems. However, the book will be of interest to anyone who is looking for a very short account on fundamental problems and principles in modern nonlinear science. (book review)

  13. Chaos: A Very Short Introduction

    International Nuclear Information System (INIS)

    Klages, R

    2007-01-01

    is also getting a bit too intricate for the complete layman, and experts may not agree on all details of the more conceptual discussions. Altogether I thoroughly enjoyed reading this book. It was a happy companion while travelling and a nice bedtime literature. It is furthermore an excellent reminder of the 'big picture' underlying nonlinear science as it applies to the real world. I will gladly recommend this book as background literature for students in my introductory course on dynamical systems. However, the book will be of interest to anyone who is looking for a very short account on fundamental problems and principles in modern nonlinear science. (book review)

  14. Three short distance structures from quantum algebras

    International Nuclear Information System (INIS)

    Kempf, A.

    1997-01-01

    Known results are reviewed and new results are given on three types of short distance structures of observables which typically appear in studies of quantum group related algebras. In particular, one of the short distance structures is shown to suggest a new mechanism for the introduction of internal symmetries

  15. The Demonstration of Short-Term Consolidation.

    Science.gov (United States)

    Jolicoeur, Pierre; Dell'Acqua, Roberto

    1998-01-01

    Results of seven experiments involving 112 college students or staff using a dual-task approach provide evidence that encoding information into short-term memory involves a distinct process termed short-term consolidation (STC). Results suggest that STC has limited capacity and that it requires central processing mechanisms. (SLD)

  16. 31 CFR 505.01 - Short title.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Short title. 505.01 Section 505.01 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF FOREIGN... CERTAIN MERCHANDISE BETWEEN FOREIGN COUNTRIES § 505.01 Short title. The regulations in this part may be...

  17. 33 CFR 401.1 - Short title.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Short title. 401.1 Section 401.1 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY DEVELOPMENT CORPORATION, DEPARTMENT OF TRANSPORTATION SEAWAY REGULATIONS AND RULES Regulations § 401.1 Short title. These regulations may be cited as the...

  18. 18 CFR 415.1 - Short title.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Short title. 415.1 Section 415.1 Conservation of Power and Water Resources DELAWARE RIVER BASIN COMMISSION ADMINISTRATIVE MANUAL BASIN REGULATIONS-FLOOD PLAIN REGULATIONS Generally § 415.1 Short title. This part shall be known...

  19. Magnetic short range order in Gd

    International Nuclear Information System (INIS)

    Child, H.R.

    1976-01-01

    Quasielastic neutron scattering has been used to investigate magnetic short range order in Gd for 80 0 K 0 K. Short range order exists throughout this range from well below T/sub C/ = 291 0 K to well above it and can be reasonably well described by an anisotropic Orstein-Zernike form for chi

  20. Hypogonadotrophic short statured with anosmia: kallmann's syndrome

    International Nuclear Information System (INIS)

    Tarique, S.; Abaidullah, S.; Cheema, T.M.; Iqbal, M.H.

    2010-01-01

    Short stature with loss of secondary sex characters can occur due to genetic disorders. One of them is Kallmann's syndrome. The condition has been noted to be present in families. It is associated with anosmia and hypogonadism. We are presenting a case of young boy who was short statured and had anosmia with multiple hormonal deficiencies. (author)

  1. The Short Circuit Model of Reading.

    Science.gov (United States)

    Lueers, Nancy M.

    The name "short circuit" has been given to this model because, in many ways, it adequately describes what happens bioelectrically in the brain. The "short-circuiting" factors include linguistic, sociocultural, attitudinal and motivational, neurological, perceptual, and cognitive factors. Research is reviewed on ways in which each one affects any…

  2. Short-Term Intercultural Psychotherapy: Ethnographic Inquiry

    Science.gov (United States)

    Seeley, Karen M.

    2004-01-01

    This article examines the challenges specific to short-term intercultural treatments and recently developed approaches to intercultural treatments based on notions of cultural knowledge and cultural competence. The article introduces alternative approaches to short-term intercultural treatments based on ethnographic inquiry adapted for clinical…

  3. Worst Asymmetrical Short-Circuit Current

    DEFF Research Database (Denmark)

    Arana Aristi, Iván; Holmstrøm, O; Grastrup, L

    2010-01-01

    In a typical power plant, the production scenario and the short-circuit time were found for the worst asymmetrical short-circuit current. Then, a sensitivity analysis on the missing generator values was realized in order to minimize the uncertainty of the results. Afterward the worst asymmetrical...

  4. Assembling the LHC short straight sections

    CERN Document Server

    Maximilien Brice

    2005-01-01

    The building where the short straight sections are being assembled, was often called ‘Lego Land’ by the workers because of the wide variety of sets of magnets and cryostats. Short straight sections contain magnets for manipulating the beam inside cryostats with liquid helium to keep the magnets at a cool 1.9 K (-271.3°C).

  5. Thoughts on Selecting a Short Story Anthology.

    Science.gov (United States)

    Logsdon, Loren

    2003-01-01

    Shares with beginning teachers advice about choosing a short story anthology and shows how a text can shape an instructor's approach to teaching short fiction. Discusses three main considerations: the students; the teacher; and the text. Identifies the author's favorite anthology and outlines nine reasons why it is a favorite. Lists five…

  6. Short-sale Constraints and Credit Runs

    DEFF Research Database (Denmark)

    Venter, Gyuri

    ), creditors with high private signals are more lenient to roll over debt, and a bank with lower asset quality remains solvent. This leads to higher allocative efficiency in the real economy. My result thus implies that the decrease in average informativeness due to short-sale constraints can be more than......This paper studies how short-sale constraints affect the informational efficiency of market prices and the link between prices and economic activity. I show that under short-sale constraints security prices contain less information. However, short-sale constraints increase the informativeness...... the price of an asset the bank holds. I show that short-selling constraints in the financial market lead to the revival of self-fulfilling beliefs about the beliefs and actions of others, and create multiple equilibria. In the equilibrium where agents rely more on public information (i.e., the price...

  7. Short circuit in deep brain stimulation.

    Science.gov (United States)

    Samura, Kazuhiro; Miyagi, Yasushi; Okamoto, Tsuyoshi; Hayami, Takehito; Kishimoto, Junji; Katano, Mitsuo; Kamikaseda, Kazufumi

    2012-11-01

    The authors undertook this study to investigate the incidence, cause, and clinical influence of short circuits in patients treated with deep brain stimulation (DBS). After the incidental identification of a short circuit during routine follow-up, the authors initiated a policy at their institution of routinely evaluating both therapeutic impedance and system impendence at every outpatient DBS follow-up visit, irrespective of the presence of symptoms suggesting possible system malfunction. This study represents a report of their findings after 1 year of this policy. Implanted DBS leads exhibiting short circuits were identified in 7 patients (8.9% of the patients seen for outpatient follow-up examinations during the 12-month study period). The mean duration from DBS lead implantation to the discovery of the short circuit was 64.7 months. The symptoms revealing short circuits included the wearing off of therapeutic effect, apraxia of eyelid opening, or dysarthria in 6 patients with Parkinson disease (PD), and dystonia deterioration in 1 patient with generalized dystonia. All DBS leads with short circuits had been anchored to the cranium using titanium miniplates. Altering electrode settings resulted in clinical improvement in the 2 PD cases in which patients had specific symptoms of short circuits (2.5%) but not in the other 4 cases. The patient with dystonia underwent repositioning and replacement of a lead because the previous lead was located too anteriorly, but did not experience symptom improvement. In contrast to the sudden loss of clinical efficacy of DBS caused by an open circuit, short circuits may arise due to a gradual decrease in impedance, causing the insidious development of neurological symptoms via limited or extended potential fields as well as shortened battery longevity. The incidence of short circuits in DBS may be higher than previously thought, especially in cases in which DBS leads are anchored with miniplates. The circuit impedance of DBS

  8. Short term memory in echo state networks

    OpenAIRE

    Jaeger, H.

    2001-01-01

    The report investigates the short-term memory capacity of echo state recurrent neural networks. A quantitative measure MC of short-term memory capacity is introduced. The main result is that MC 5 N for networks with linear Output units and i.i.d. input, where N is network size. Conditions under which these maximal memory capacities are realized are described. Several theoretical and practical examples demonstrate how the short-term memory capacities of echo state networks can be exploited for...

  9. Preliminary list of plant invaders in Montenegro

    Directory of Open Access Journals (Sweden)

    Stešević, D.

    2010-12-01

    Full Text Available Due to the fact that Invasive alien species (IAS are considered to be the second cause of global biodiversity loss after direct habitat destruction and have adverse environmental, economic and social impacts from the local level upwards, in last decades investigations of alien flora of Montenegro are intensified. In this paper we are presenting a preliminary list of IAS, with the aim to provide a basic data on IAS in Montenegro, to enable future monitoring and to draw attention on the problems which expansion of IAS is bringing with itself. The list consists of 50 plant taxa species and supspecies level.

  10. Preliminary list of plant invaders in Montenegro

    OpenAIRE

    Stešević, D.; Petrović, D.

    2010-01-01

    Due to the fact that Invasive alien species (IAS) are considered to be the second cause of global biodiversity loss after direct habitat destruction and have adverse environmental, economic and social impacts from the local level upwards, in last decades investigations of alien flora of Montenegro are intensified. In this paper we are presenting a preliminary list of IAS, with the aim to provide a basic data on IAS in Montenegro, to enable future monitoring and to draw attention o...

  11. The Soviet Decision to Invade Czechoslovakia

    Science.gov (United States)

    1975-09-01

    inuary 1976 DDC - ’■’ rv > Canoron Station O T "> 1 ." Mexancria The caveat appearing on the title pi c.r. ol: Center for hib- avanced^earch...Soviets viewed the political developments in Czechoslovakia in 1968 with alarm bordering on paranoia, conditioned by the "dagger" phobia and by...published its Action Program entitled "The Czechoslovak Road to Socialism ," a program described by a Western authority as "a remarkable

  12. Open Days Guide: Kids invade CERN!

    CERN Multimedia

    Katarina Anthony

    2013-01-01

    Keep the whole family entertained with this mix of zany activities, performances and visits.   ATLAS Adventures Using the building blocks of the Universe – LEGO, of course – kids will be invited to make their own model of the ATLAS experiment. Each model will be entered into a competition for some great ATLAS prizes! Over-7s will love working on the giant ATLAS puzzle, and adults will be on hand for the little ones who want to put in a piece. (Ages 4 and up) Map: Point 1 - ATLAS experiment CMS’s Battle of the Bosons Quark? Higgs? Proton? Take your pick. At “Paint-a-Particle” face painting, kids will be “transformed” into their favourite particles! They’ll also get a chance to work on a massive wood-block version of the CMS detector. The whole family is invited to “fight fire” and win prizes: look out for portable fire hydrants to find out more! (Ages 3 and up) Map: Point 5 - CM...

  13. Corticosterone regulation in house sparrows invading Senegal.

    Science.gov (United States)

    Martin, Lynn B; Kilvitis, Holly J; Thiam, Massamba; Ardia, Daniel R

    2017-09-01

    What traits help organisms expand their ranges? Several behavioral and life history traits have been identified, but physiological and especially endocrinological factors have been minimally considered. Here, we asked whether steroid hormonal responses to stressors might be important. Previously, we found that corticosterone (CORT) responses to a standard restraint stressor were stronger at a range edge than at the core of the recent house sparrow (Passer domesticus) invasion of Kenya. In related work in the same system, we found that various behaviors (exploratory activity, responses to novelty, etc.) that are affected by CORT in other systems varied among sparrow populations in a manner that would suggest that CORT regulation directly influenced colonization success; birds at the range edge were less averse to novelty and more exploratory than birds from the core. Here, we asked whether the pattern in CORT regulation we observed in Kenya was also detectable in the more recent (∼1970) and independent invasion of Senegal. We found, as in Kenya, that Senegalese range-edge birds mounted stronger CORT responses to restraint than core birds. We also found lower baseline CORT in range-edge than core Senegalese birds, but little evidence for effects of individual sex, body mass or body size on CORT. Follow-up work will be necessary to resolve whether CORT regulation in Senegal (and Kenya) actively facilitated colonization success, but our work implicates glucocorticoids as a mediator of range expansion success, making stress responses potentially useful biomarkers of invasion risk. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Epibiotic pressure contributes to biofouling invader success.

    Science.gov (United States)

    Leonard, Kaeden; Hewitt, Chad L; Campbell, Marnie L; Primo, Carmen; Miller, Steven D

    2017-07-12

    Reduced competition is a frequent explanation for the success of many introduced species. In benthic marine biofouling communities, space limitation leads to high rates of overgrowth competition. Some species can utilise other living organisms as substrate (epibiosis), proffering a competitive advantage for the epibiont. Additionally, some species can prevent or reduce epibiotic settlement on their surfaces and avoid being basibionts. To test whether epibiotic pressure differs between native and introduced species, we undertook ex situ experiments comparing bryozoan larval settlement to determine if introduced species demonstrate a greater propensity to settle as epibionts, and a reduced propensity to be basibionts, than native species. Here we report that introduced species opportunistically settle on any space (bare, native, or introduced), whereas native species exhibit a strong tendency to settle on and near other natives, but avoid settling on or near introduced basibionts. In addition, larvae of native species experience greater larval wastage (mortality) than introduced species, both in the presence and absence of living substrates. Introduced species' ability to settle on natives as epibionts, and in turn avoid epibiosis as basibionts, combined with significantly enhanced native larval wastage, provides a comprehensive suite of competitive advantages contributing to the invasion success of these biofouling species.

  15. Zebra mussels invade Lake Erie muds

    Science.gov (United States)

    Berkman, Paul Arthur; Haltuch, Melissa A.; Tichich, Emily; Garton, David W.; Kennedy, Gregory W.; Gannon, John E.; Mackey, Scudder D.; Fuller, Jonathan A.; Liebenthal, Dale L.

    1998-01-01

    Zebra mussels (Dreissena polymorpha) originated in western Russia but have now become widespread in Europe and North America. They are widely known for their conspicuous invasion of rocks and other hard substrates in North American and European watersheds. We have found beds of zebra mussels directly colonizing sand and mud sediments each year across hundreds of square kilometres of North America's Lake Erie. This transformation of sedimentary habitats into mussel beds represents an unforeseen change in the invasive capacity of this species.

  16. Thoughts Invade Us: Lexical Cognition and Cyberspace

    Science.gov (United States)

    2017-06-01

    enables us to learn a language to begin with. In the same way that technology is socially constructed but later exerts influence within a...http://www.stratcom.mil/ Media /Factsheets/Factsheet- View/Article/960492/us-cyber-command-uscybercom/. Wendt, Alexander. Social Theory of...perspective extends a purely social construction of cyberspace, where the domain changes simply as an extension of social dynamics, utility, and

  17. Mangrove forests: a tough system to invade

    Science.gov (United States)

    Ariel E. Lugo

    1998-01-01

    Tropical forests are the most species-rich forests in the world. As many as 225 tree species per hectare have been reported in these ecosystems, values that are equivalent to almost finding a different tree species every other tree encountered in the forest. Under some conditions, tree species richness decreases in tropical forests. For example, Hart et al. (1989)...

  18. Practical applications of short-lived radioisotopes

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1963-01-15

    The advantages of the use of short-lived radioisotopes in agriculture, food industry and medicine as well as some industrial uses are discussed. Methods for isotope production in small research reactors and laboratories are presented

  19. SPS, preassembly of short straight sections

    CERN Multimedia

    1975-01-01

    Short straight sections were preassembled with their vacuum chambers, ready for installation in the SPS. Here we see two, containing sextupoles for chromaticity adjustment. See also 7501017, 7501018, and Annual Report 1976, p.174.

  20. SPS, short straight section with sextupole

    CERN Multimedia

    CERN PhotoLab

    1975-01-01

    Short straight sections were preassembled with their vacuum chambers, ready for installation in the SPS. This one contains a sextupole for chromaticity adjustment. See also 7501017, 7501009X, and Annual Report 1974, p.174.

  1. Short-distance structure of instantons

    International Nuclear Information System (INIS)

    Carlitz, R.D.; Creamer, D.B.

    The short distance structure of a quark propagator in an instanton background field is analyzed. This analysis describes the influence of instantons upon physical processes such as electron-position annihilation and the deep inelastic scattering of leptons from hadrons

  2. Minimalism in the modern short story

    Directory of Open Access Journals (Sweden)

    A Razi

    2009-09-01

    Full Text Available Short story has recently become the focus of attention in the late decades in Iran. The expanding value of writing short story is actually a reasonable outcome of the dominance of minimalism- a movement which is based upon simplicity and shortness. Minimalist writers, leaving out redundant features of narration, mainly focus on essentialities through applying a variety of techniques such as cuttings from the interesting moments of real life, evading introduction, applying inter-referents, choice of words, short stanzas and sentences and so on. Looking upon critic’s opinion about such a tendency over the past and present, this article will come up with a brief explanation of the properties of such stories. Finally a sample story “candles will never go dead” will be analyzed and discussed in the lights of such techniques.

  3. Giant pubertal prolactinoma: Complete resolution following short ...

    African Journals Online (AJOL)

    2016-04-06

    Apr 6, 2016 ... disappeared in a short time with cabergoline treatment. Key words: ... Hyperprolactinemia may cause impotence and hypogonadism in adult men, and rarely ... safe treatment method for male patients with giant prolactinoma.

  4. Short Communication: Gender Bias and Stigmatization against ...

    African Journals Online (AJOL)

    Short Communication: Gender Bias and Stigmatization against Women Living with ... In Ethiopia, HIV/AIDS is highly stigmatized due to the fact that sexual ... bias, socio-economic situations and traditional beliefs contribute, individually and in ...

  5. A Novel Method for Short Distance Measurements

    International Nuclear Information System (INIS)

    Fernandez, M.G.; Ferrando, A.; Josa, M.I.; Molinero, A.; Oller, J.C.; Arce, P.; Calvo, E.; Figueroa, C.F.; Garcia, C.F.; Rodigrido, T.; Vila, I.; Virto, A.L.

    1998-01-01

    A new, accurate and un expensive device for measuring short distances, intended for monitoring in LHC experiments is presented. Data taken with a very simple prototype are shown and performance is extracted. (Author) 4 refs

  6. Modern treatment of short bowel syndrome

    DEFF Research Database (Denmark)

    Jeppesen, Palle B

    2013-01-01

    Recently, the US Food and Drug Administration and the European Medicines Agency approved the glucagon-like peptide 2 analogue, teduglutide, for the treatment of short bowel syndrome (SBS), and this review describes the physiological basis for its clinical use.......Recently, the US Food and Drug Administration and the European Medicines Agency approved the glucagon-like peptide 2 analogue, teduglutide, for the treatment of short bowel syndrome (SBS), and this review describes the physiological basis for its clinical use....

  7. Operator expansion at short distance in QCD

    Energy Technology Data Exchange (ETDEWEB)

    Hubschmid, W [Bern Univ. (Switzerland). Inst. fuer Theoretische Physik; Mallik, S [Karlsruhe Univ. (T.H.) (Germany, F.R.). Inst. fuer Theoretische Kernphysik

    1982-11-01

    We present a method of calculating coefficients of gluon operators in the operator product expansion of two-point functions at short distance. It is based on a short-distance expansion of the singular part of the quark propagator in the gluon field, the latter being treated as external. We verify in full generality that the spin zero, gluon operator of dimension six does not contribute to the two-point functions of quark bilinears.

  8. Fund managers’ contracts and short-termism

    OpenAIRE

    Casamatta, Catherine; Pouget, Sébastien

    2009-01-01

    This paper considers the problem faced by long-term investors who have to delegate the management of their money to professional fund managers. Investors can earn profits if fund managers collect long-term information. We investigate to what extent the delegation of fund management prevents long-term information acquisition, inducing short-termism. We also study the design of long-term fund managers' compensation contracts. Absent moral hazard, short-termism arises only because of the cost...

  9. Fast Weight Long Short-Term Memory

    OpenAIRE

    Keller, T. Anderson; Sridhar, Sharath Nittur; Wang, Xin

    2018-01-01

    Associative memory using fast weights is a short-term memory mechanism that substantially improves the memory capacity and time scale of recurrent neural networks (RNNs). As recent studies introduced fast weights only to regular RNNs, it is unknown whether fast weight memory is beneficial to gated RNNs. In this work, we report a significant synergy between long short-term memory (LSTM) networks and fast weight associative memories. We show that this combination, in learning associative retrie...

  10. Regional variation in short distance homogamy

    OpenAIRE

    Haandrikman, Karen; van Wissen, Leo

    2011-01-01

    A third of all Dutch cohabiters choose a partner from the same municipality, so-called short distance homogamy. This article analyses the regional variation in this phenomenon, and it explains this variation in terms of geographical, socioeconomic, demographic and cultural determinants. Population register data on all new cohabiters in 2004 were used. Regression methods were employed to explain spatial patterns. Regional variation in short distance homogamy is largely explained by geographica...

  11. Observations of short gamma-ray bursts.

    Science.gov (United States)

    Fox, Derek B; Roming, Peter W A

    2007-05-15

    We review recent observations of short-hard gamma-ray bursts and their afterglows. The launch and successful ongoing operations of the Swift satellite, along with several localizations from the High-Energy Transient Explorer mission, have provoked a revolution in short-burst studies: first, by quickly providing high-quality positions to observers; and second, via rapid and sustained observations from the Swift satellite itself. We make a complete accounting of Swift-era short-burst localizations and proposed host galaxies, and discuss the implications of these observations for the distances, energetics and environments of short bursts, and the nature of their progenitors. We then review the physical modelling of short-burst afterglows: while the simplest afterglow models are inadequate to explain the observations, there have been several notable successes. Finally, we address the case of an unusual burst that threatens to upset the simple picture in which long bursts are due to the deaths of massive stars, and short bursts to compact-object merger events.

  12. Short-term memory across eye blinks.

    Science.gov (United States)

    Irwin, David E

    2014-01-01

    The effect of eye blinks on short-term memory was examined in two experiments. On each trial, participants viewed an initial display of coloured, oriented lines, then after a retention interval they viewed a test display that was either identical or different by one feature. Participants kept their eyes open throughout the retention interval on some blocks of trials, whereas on others they made a single eye blink. Accuracy was measured as a function of the number of items in the display to determine the capacity of short-term memory on blink and no-blink trials. In separate blocks of trials participants were instructed to remember colour only, orientation only, or both colour and orientation. Eye blinks reduced short-term memory capacity by approximately 0.6-0.8 items for both feature and conjunction stimuli. A third, control, experiment showed that a button press during the retention interval had no effect on short-term memory capacity, indicating that the effect of an eye blink was not due to general motoric dual-task interference. Eye blinks might instead reduce short-term memory capacity by interfering with attention-based rehearsal processes.

  13. Short Implants: New Horizon in Implant Dentistry.

    Science.gov (United States)

    Jain, Neha; Gulati, Manisha; Garg, Meenu; Pathak, Chetan

    2016-09-01

    The choice of implant length is an essential factor in deciding the survival rates of these implants and the overall success of the prosthesis. Placing an implant in the posterior part of the maxilla and mandible has always been very critical due to poor bone quality and quantity. Long implants can be placed in association with complex surgical procedures such as sinus lift and bone augmentation. These techniques are associated with higher cost, increased treatment time and greater morbidity. Hence, there is need for a less invasive treatment option in areas of poor bone quantity and quality. Data related to survival rates of short implants, their design and prosthetic considerations has been compiled and structured in this manuscript with emphasis on the indications, advantages of short implants and critical biomechanical factors to be taken into consideration when choosing to place them. Studies have shown that comparable success rates can be achieved with short implants as those with long implants by decreasing the lateral forces to the prosthesis, eliminating cantilevers, increasing implant surface area and improving implant to abutment connection. Short implants can be considered as an effective treatment alternative in resorbed ridges. Short implants can be considered as a viable treatment option in atrophic ridge cases in order to avoid complex surgical procedures required to place long implants. With improvement in the implant surface geometry and surface texture, there is an increase in the bone implant contact area which provides a good primary stability during osseo-integration.

  14. SITE WIDE SHORT CIRCUIT STUDY ASSESSMENT

    International Nuclear Information System (INIS)

    CARRATT, R.T.

    2004-01-01

    The Department of Energy requested that Fluor Hanford develop a plan to update the electrical distribution studies for FH managed facilities. Toward this end, an assessment of FH's nuclear facilities was performed to determine whether a current short circuit study of the facility electrical distribution system exists, and the status of such study. This report presents the methodology and results of that assessment. The assessment identified 29 relevant facilities. Of these, a short circuit study could not be identified for 15 facilities. A short circuit study was found to exist for fourteen facilities, however, of these 14, four were not released into a controlled document system, and two were not performed for the entire electrical distribution system. It is recommended that for four of the facilities no further action is required based upon the limited nature of the existing electrical system, or as in the case of PFP, the status of the existing short circuit study was determined adequate. For the majority of the facilities without a short circuit study, it is recommended that one is performed, and released into a controlled document system. Two facilities require further evaluation due to missing or conflicting documentation. For the remainder of the facilities, the recommendations are to review and revise as appropriate the existing study, and release into a controlled document system. A summation of the recommendations is presented

  15. Nutritive support in short Bowel syndrome (sbs

    Directory of Open Access Journals (Sweden)

    Simić Dušica

    2003-01-01

    Full Text Available Short bowel syndrome most commonly result after bowel resection for necrosis of the bowel. It may be caused by arterial or venous thrombosis, volvolus and in children, necrotizing enterocolitis. The other causes are Crohn,s disease intestinal atresia. The factors influencing the risk on short bowel syndrome are the remaining length of the small bowel, the age of onset, the length of the colon, the presence or absence of the ileo-coecal valve and the time after resection. Besides nutritional deficiencies there some other consequences of extensive resections of the small intestine (gastric acid hypersecretion, d-lactic acidosis, nephrolithiasis, cholelithiasis, which must be diagnosed, treated, and if possible, prevented. With current therapy most patients with short bowel have normal body mass index and good quality of life.

  16. Short pulse laser systems for biomedical applications

    CERN Document Server

    Mitra, Kunal

    2017-01-01

    This book presents practical information on the clinical applications of short pulse laser systems and the techniques for optimizing these applications in a manner that will be relevant to a broad audience, including engineering and medical students as well as researchers, clinicians, and technicians. Short pulse laser systems are useful for both subsurface tissue imaging and laser induced thermal therapy (LITT), which hold great promise in cancer diagnostics and treatment. Such laser systems may be used alone or in combination with optically active nanoparticles specifically administered to the tissues of interest for enhanced contrast in imaging and precise heating during LITT. Mathematical and computational models of short pulse laser-tissue interactions that consider the transient radiative transport equation coupled with a bio-heat equation considering the initial transients of laser heating were developed to analyze the laser-tissue interaction during imaging and therapy. Experiments were first performe...

  17. Short-termism in the European Union

    DEFF Research Database (Denmark)

    Strand, Therese

    2016-01-01

    The 2007–08 global financial crisis gave rise to an extensive debate in the United States (US) on short-termism and its influence on agency relationships, incentives, and fiduciary duties. This debate and the consecutive legal creativity of US policymakers display spillover effects and constitute...... an influential source of inspiration for politicians and lawmakers in foreign jurisdictions. The European Commission currently proposes to amend the Shareholder Rights Directive (2007/36/EC) to counterbalance the financial sector’s alleged triumph over industry. The initiative is motivated primarily...... that the short-termism concept, despite its contemporary authority in the post-financial crisis era on both sides of the Atlantic, is misguided, and even more so in the European context. The Article concludes that the proposed amendments should not be expected to solve short-termism problems or alter...

  18. Estimating the short-circuit impedance

    DEFF Research Database (Denmark)

    Nielsen, Arne Hejde; Pedersen, Knud Ole Helgesen; Poulsen, Niels Kjølstad

    1997-01-01

    A method for establishing a complex value of the short-circuit impedance from naturally occurring variations in voltage and current is discussed. It is the symmetrical three phase impedance at the fundamental grid frequency there is looked for. The positive sequence components in voltage...... and current are derived each period, and the short-circuit impedance is estimated from variations in these components created by load changes in the grid. Due to the noisy and dynamic grid with high harmonic distortion it is necessary to threat the calculated values statistical. This is done recursively...... through a RLS-algorithm. The algorithms have been tested and implemented on a PC at a 132 kV substation supplying a rolling mill. Knowing the short-circuit impedance gives the rolling mill an opportunity to adjust the arc furnace operation to keep flicker below a certain level. Therefore, the PC performs...

  19. Radiation degradation of short-cotton linters

    International Nuclear Information System (INIS)

    Ma Zue Teh; Zhou Rui Min

    1984-01-01

    Radiation degradation of short-cotton linters has been studied by using X-ray diffraction, an infrared spectrometer and a viscosimeter. Average molecular weight and crystallinity of short-cotton linters and the change of reducing sugar in γ-radiation degradation were examined. It was found that cellulosic saccharification in hydrolysis was enhanced with preirradiation of linter. This probably resulted from the radiation induced change of cellulosic structure. Sensitizers to promote radiation degradation effect were investigated. Carbon tetrachloride has been found to be effective. (author)

  20. Heating Augmentation for Short Hypersonic Protuberances

    Science.gov (United States)

    Mazaheri, Ali R.; Wood, William A.

    2008-01-01

    Computational aeroheating analyses of the Space Shuttle Orbiter plug repair models are validated against data collected in the Calspan University of Buffalo Research Center (CUBRC) 48 inch shock tunnel. The comparison shows that the average difference between computed heat transfer results and the data is about 9.5%. Using CFD and Wind Tunnel (WT) data, an empirical correlation for estimating heating augmentation on short hypersonic protuberances (k/delta less than 0.3) is proposed. This proposed correlation is compared with several computed flight simulation cases and good agreement is achieved. Accordingly, this correlation is proposed for further investigation on other short hypersonic protuberances for estimating heating augmentation.

  1. libgapmis: extending short-read alignments.

    Science.gov (United States)

    Alachiotis, Nikolaos; Berger, Simon; Flouri, Tomáš; Pissis, Solon P; Stamatakis, Alexandros

    2013-01-01

    A wide variety of short-read alignment programmes have been published recently to tackle the problem of mapping millions of short reads to a reference genome, focusing on different aspects of the procedure such as time and memory efficiency, sensitivity, and accuracy. These tools allow for a small number of mismatches in the alignment; however, their ability to allow for gaps varies greatly, with many performing poorly or not allowing them at all. The seed-and-extend strategy is applied in most short-read alignment programmes. After aligning a substring of the reference sequence against the high-quality prefix of a short read--the seed--an important problem is to find the best possible alignment between a substring of the reference sequence succeeding and the remaining suffix of low quality of the read--extend. The fact that the reads are rather short and that the gap occurrence frequency observed in various studies is rather low suggest that aligning (parts of) those reads with a single gap is in fact desirable. In this article, we present libgapmis, a library for extending pairwise short-read alignments. Apart from the standard CPU version, it includes ultrafast SSE- and GPU-based implementations. libgapmis is based on an algorithm computing a modified version of the traditional dynamic-programming matrix for sequence alignment. Extensive experimental results demonstrate that the functions of the CPU version provided in this library accelerate the computations by a factor of 20 compared to other programmes. The analogous SSE- and GPU-based implementations accelerate the computations by a factor of 6 and 11, respectively, compared to the CPU version. The library also provides the user the flexibility to split the read into fragments, based on the observed gap occurrence frequency and the length of the read, thereby allowing for a variable, but bounded, number of gaps in the alignment. We present libgapmis, a library for extending pairwise short-read alignments. We

  2. Electron dynamics inside short-coherence systems

    International Nuclear Information System (INIS)

    Ferrari, Giulio; Bordone, Paolo; Jacoboni, Carlo

    2006-01-01

    We present theoretical results on electron dynamics inside nanometric systems, where the coherence of the electron ensemble is maintained in a very short region. The contacts are supposed to spoil such a coherence, therefore the interference processes between the carrier wavefunction and the internal potential profile can be affected by the proximity of the contacts. The problem has been analysed by using the Wigner-function formalism. For very short devices, transport properties, such as tunnelling through potential barriers, are significantly influenced by the distance between the contacts

  3. Short-range correlations with pseudopotentials

    International Nuclear Information System (INIS)

    Osman, A.

    1976-01-01

    Short-range correlations in nuclei are considered on an unitary-model operator approach. Short-range pseudopotentials have been added to achieve healing in the correlated wave functions. With the introduction of the pseudopotentials, correlated basis wave functions are constructed. The matrix element for effective interaction in nuclei is developed. The required pseudopotentials have been calculated for the Hamda-Johnston, Yale and Reid potentials and for the nuclear nucleon-nucleon potential A calculated by us according to meson exchange between nucleons. (Osman, A.)

  4. Short wavelength sources and atoms and ions

    International Nuclear Information System (INIS)

    Kennedy, E.T.

    2008-01-01

    The interaction of ionizing radiation with atoms and ions is a key fundamental process. Experimental progress has depended in particular on the development of short wavelength light sources. Laser-plasma and synchrotron sources have been exploited for several decades and most recently the development of short wavelength Free Electron Laser (FEL) sources is revolutionizing the field. This paper introduces laser plasma and synchrotron sources through examples of their use in studies of the interaction of ionizing radiation with atoms and ions, ranging from few-electron atomic and ionic systems to the many-electron high atomic number actinides. The new FEL source (FLASH) at DESY is introduced. (author)

  5. Certain features of FELs with short bunches

    International Nuclear Information System (INIS)

    Lebedev, A.N.

    2006-01-01

    The report is devoted to physics of free electron lasers operating in the short-wave domain where the bunch length could be less than the undulator length in the proper frame. Then the current component of the signal is locked within the bunch as in a cavity, while the electromagnetic component propagates freely. In contrast with gyrotrons where this regime can be of interest only for wavelengths comparable with the bunch length, we consider short waves in a bunch of arbitrary profile. Both amplification of an external harmonic signal and SASE regime, i.e. selective amplification of proper noises, are investigated

  6. Women stereotypes in Shi Zhecun's short stories.

    Science.gov (United States)

    Rosenmeier, Christopher

    2010-01-01

    This article analyses the representation of women in two 1933 short story collections by Shi Zhecun: An Evening of Spring Rain and Exemplary Conduct of Virtuous Women. It discusses how the New Woman image was a site of contestation in Republican China, and argues that Shi Zhecun’s short stories contain four basic stereotypes: the enigmatic woman, the estranged wife, the prostitute, and the inhibited woman. Using these narratives of women and how they were perceived by men, Shi Zhecun deconstructed the New Woman image by subverting the various ways modernity was projected onto women.

  7. Short-term response of Holcus lanatus L. (Common Velvetgrass) to chemical and manual control at Yosemite National Park, USA

    Science.gov (United States)

    Jones, Laura J.; Ostoja, Steven M.; Brooks, Matthew L.; Hutten, Martin

    2015-01-01

    One of the highest priority invasive species at both Yosemite and Sequoia and Kings Canyon national parks is Holcus lanatus L. (common velvetgrass), a perennial bunchgrass that invades mid-elevation montane meadows. Despite velvetgrass being a high priority species, there is little information available on control techniques. The goal of this project was to evaluate the short-term response of a single application of common chemical and manual velvetgrass control techniques. The study was conducted at three montane sites in Yosemite National Park. Glyphosate spot-spray treatments were applied at 0.5, 1.0, 1.5, and 2.0% concentrations, and compared with hand pulling to evaluate effects on cover of common velvetgrass, cover of other plant species, and community species richness. Posttreatment year 1 cover of common velvetgrass was 12.1% ± 1.6 in control plots, 6.3% ± 1.5 averaged over the four chemical treatments (all chemical treatments performed similarly), and 13.6% ± 1.7 for handpulled plots. This represents an approximately 50% reduction in common velvetgrass cover in chemically- treated plots recoded posttreatment year 1 and no statistically significant reduction in hand pulled plots compared with controls. However, there was no treatment effect in posttreatment year 2, and all herbicide application rates performed similarly. In addition, there were no significant treatment effects on nontarget species or species richness. These results suggest that for this level of infestation and habitat type, (1) one year of hand pulling is not an effective control method and (2) glyphosate provides some level of control in the short-term without impact to nontarget plant species, but the effect is temporary as a single year of glyphosate treatment is ineffective over a two-year period.

  8. An Active Immune Defense with a Minimal CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) RNA and without the Cas6 Protein*

    Science.gov (United States)

    Maier, Lisa-Katharina; Stachler, Aris-Edda; Saunders, Sita J.; Backofen, Rolf; Marchfelder, Anita

    2015-01-01

    The prokaryotic immune system CRISPR-Cas (clustered regularly interspaced short palindromic repeats-CRISPR-associated) is a defense system that protects prokaryotes against foreign DNA. The short CRISPR RNAs (crRNAs) are central components of this immune system. In CRISPR-Cas systems type I and III, crRNAs are generated by the endonuclease Cas6. We developed a Cas6b-independent crRNA maturation pathway for the Haloferax type I-B system in vivo that expresses a functional crRNA, which we termed independently generated crRNA (icrRNA). The icrRNA is effective in triggering degradation of an invader plasmid carrying the matching protospacer sequence. The Cas6b-independent maturation of the icrRNA allowed mutation of the repeat sequence without interfering with signals important for Cas6b processing. We generated 23 variants of the icrRNA and analyzed them for activity in the interference reaction. icrRNAs with deletions or mutations of the 3′ handle are still active in triggering an interference reaction. The complete 3′ handle could be removed without loss of activity. However, manipulations of the 5′ handle mostly led to loss of interference activity. Furthermore, we could show that in the presence of an icrRNA a strain without Cas6b (Δcas6b) is still active in interference. PMID:25512373

  9. An active immune defense with a minimal CRISPR (clustered regularly interspaced short palindromic repeats) RNA and without the Cas6 protein.

    Science.gov (United States)

    Maier, Lisa-Katharina; Stachler, Aris-Edda; Saunders, Sita J; Backofen, Rolf; Marchfelder, Anita

    2015-02-13

    The prokaryotic immune system CRISPR-Cas (clustered regularly interspaced short palindromic repeats-CRISPR-associated) is a defense system that protects prokaryotes against foreign DNA. The short CRISPR RNAs (crRNAs) are central components of this immune system. In CRISPR-Cas systems type I and III, crRNAs are generated by the endonuclease Cas6. We developed a Cas6b-independent crRNA maturation pathway for the Haloferax type I-B system in vivo that expresses a functional crRNA, which we termed independently generated crRNA (icrRNA). The icrRNA is effective in triggering degradation of an invader plasmid carrying the matching protospacer sequence. The Cas6b-independent maturation of the icrRNA allowed mutation of the repeat sequence without interfering with signals important for Cas6b processing. We generated 23 variants of the icrRNA and analyzed them for activity in the interference reaction. icrRNAs with deletions or mutations of the 3' handle are still active in triggering an interference reaction. The complete 3' handle could be removed without loss of activity. However, manipulations of the 5' handle mostly led to loss of interference activity. Furthermore, we could show that in the presence of an icrRNA a strain without Cas6b (Δcas6b) is still active in interference. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  10. Cinematic diamonds : narrative storytelling strategies in short fiction film

    OpenAIRE

    Cantell, Saara (kirjoittaja); Jeremiah, Fleur (kääntäjä)

    2012-01-01

    Saara Cantell proposes and discusses alternative ways of approaching short film. This book emphasizes short film as an independent and challenging cinematic art form of its own right. The "mystery" of short film is approached by examining the aesthetics of other short forms, The structural parallels between e.g. jokes and short films, as well as narrative strategies found in poetry, offer meaningful references. The research consists of both the analysis of selected short films and the five sh...

  11. The Long and the Short of It: The Use of Short Films in the German Classroom

    Science.gov (United States)

    Sundquist, John

    2010-01-01

    This article focuses on the benefits of using short film in the German classroom at the secondary or post-secondary level. The article addresses a number of characteristics of short films that lend themselves well to the classroom, including their abbreviated length, artistic innovation, and compact storytelling. In addition to discussing specific…

  12. Measuring short distance dispersal of Alliaria petiolata and determining potential long distance dispersal mechanisms

    Directory of Open Access Journals (Sweden)

    Christopher A. Loebach

    2018-03-01

    were dropped on furs and rotated as before, then the furs were agitated for one hour. The seeds retained in the fur were counted. Results For the seed dispersal experiment, the 2Dt function provided the best fit and was the most biologically meaningful. It predicted that seed density rapidly declined with distance from the point source. Mean dispersal distance was 0.52 m and 95% of seeds dispersed within 1.14 m. The epizoochory field experiment showed increased mammal activity and A. petiolata seedlings in germination trays of the MIT compared to control. Laboratory studies showed 3–26% of seeds were attached and retained by raccoon and deer fur. Retention significantly increased if either seed or fur were wet (57–98%. Discussion Without animal seed vectors, most seeds fall within a short distance of the seed source; however, long distance dispersal may be accomplished by epizoochory. Our data are consistent with A. petiolata’s widespread distribution and development of dense clusters of the species in invaded areas.

  13. Transient nanobubbles in short-time electrolysis

    NARCIS (Netherlands)

    Svetovoy, Vitaly; Sanders, Remco G.P.; Elwenspoek, Michael Curt

    2013-01-01

    Water electrolysis in a microsystem is observed and analyzed on a short-time scale of ∼10 μs. The very unusual properties of the process are stressed. An extremely high current density is observed because the process is not limited by the diffusion of electroactive species. The high current is

  14. Compression of Short Text on Embedded Systems

    DEFF Research Database (Denmark)

    Rein, S.; Gühmann, C.; Fitzek, Frank

    2006-01-01

    The paper details a scheme for lossless compression of a short data series larger than 50 bytes. The method uses arithmetic coding and context modelling with a low-complexity data model. A data model that takes 32 kBytes of RAM already cuts the data size in half. The compression scheme just takes...

  15. Visual Short-Term Memory Complexity

    DEFF Research Database (Denmark)

    Sørensen, Thomas Alrik

    Several recent studies have explored the nature and limits of visual short-term memory (VSTM) (e.g. Luck & Vogel, 1997). A general VSTM capacity limit of about 3 to 4 letters has been found, thus confirming results from earlier studies (e.g. Cattell, 1885; Sperling, 1960). However, Alvarez...

  16. Short-timescale variability in cataclysmic binaries

    International Nuclear Information System (INIS)

    Cordova, F.A.; Mason, K.O.

    1982-01-01

    Rapid variability, including flickering and pulsations, has been detected in cataclysmic binaries at optical and x-ray frequencies. In the case of the novalike variable TT Arietis, simultaneous observations reveal that the x-ray and optical flickering activity is strongly correlated, while short period pulsations are observed that occur at the same frequencies in both wavelength bands

  17. SHORT COMMUNICATIONS, NOTES AND REPORTS Record of ...

    African Journals Online (AJOL)

    Campbell Murn

    50. SHORT COMMUNICATIONS, NOTES AND. REPORTS. Record of Cinereous Vulture Aegypius monachus from Mukundara Hills Tiger Reserve, Rajasthan,. India. Sailaja Nayak1*, Sunny Shah2 and Jimmy Borah2 .... Prey status and abundance in Mukundara Hills Tiger. Reserve. Technical Report, WWF-India. Rao, J.P. ...

  18. The short circuit instability in protoplanetary disks

    DEFF Research Database (Denmark)

    Hubbard, A.; McNally, C.P.; Mac Low, M.M.

    2013-01-01

    We introduce a magneto-hydrodynamic instability which occurs, among other locations, in the inner, hot regions of protoplanetary disks, and which alters the way in which resistive dissipation of magnetic energy into heat proceeds. This instability can be likened to both an electrical short circui...

  19. Wheat shorts in diets of gestating swine.

    Science.gov (United States)

    Young, L G; King, G L

    1981-03-01

    Sixty-four gilts were assigned to be bred at first or third observed estrus and fed gestation diets of pelleted wheat shorts with a free choice mineral-vitamin supplement or fortified corn-soybean meal. Only the dietary effects are included in this report. The gilts were fed their respective diets starting at 25 days after insemination. The experiment continued through three gestation-lactation cycles. Females fed the wheat shorts received less digestible energy during gestation and weighed less at day 109 of gestation and days 1, 7 and 21 of lactation in each of the three gestation-lactation periods. Females fed wheat shorts had lighter pigs at birth, weaned more pigs per litter in each parity and returned to estrus more slowly after weaning than females fed a corn-soybean meal diet. Results of a metabolism trial conducted with 12 barrows revealed that wheat shorts contained approximately 2.93 kcal digestible energy/kg dry matter and had an apparent protein digestibility of 72%, compared with values of 4.0 kcal and 86%, respectively, for the corn-soybean meal diets.

  20. Blacks in Pop Music: A Short Story.

    Science.gov (United States)

    Rickelman, Melinda

    1991-01-01

    A short history of black pop music includes artists who have changed pop music or culture and highlights from the 1920s into the 1980s, from Fats Waller to Michael Jackson. In black pop music, there is a direct line of influence from the sharecropper to the current Top 40. (SLD)

  1. Short Historical Fiction To Get Children Reading.

    Science.gov (United States)

    Sullivan, Kathleen

    1997-01-01

    Provides an annotated bibliography of short historical fiction and picture books for readers in grades K-8. Includes a list of selected Caldecott and Newbery winners with historical themes or backgrounds and a list of activity books featuring Spanish exploration in Mexico, Roman art and fashion, medieval Europe, and cowboys. (PEN)

  2. Cryptanalysis of 'less short' RSA secret exponents

    NARCIS (Netherlands)

    Verheul, E.R.; Tilborg, van H.C.A.

    1997-01-01

    In some applications of RSA, it is desirable to have a short secret exponent d. Wiener [6], describes a technique to use continued fractions (CF) in a cryptanalytic attack on an RSA cryptosystem having a ‘short’ secret exponent. Let n=p¿·¿q be the modulus of the system. In the typical case that

  3. Introduction to impedance for short relativistic bunches

    International Nuclear Information System (INIS)

    Morton, P.L.

    1993-02-01

    The purpose of this paper is to introduce the concept of impedance to calculate the wake field forces left behind by a short bunch which travels at relativistic speed through a structure with discontinuities. We will try to be as intuitive as possible and leave the more rigorous derivations to the second paper on this subject by J. Wang

  4. A Short Introduction to Kolmogorov Complexity

    NARCIS (Netherlands)

    Nannen, Volker

    2010-01-01

    This is a short introduction to Kolmogorov complexity and information theory. The interested reader is referred to the literature, especially the textbooks [CT91] and [LV97] which cover the elds of information theory and Kolmogorov complexity in depth and with all the necessary rigor.

  5. Reading Abilities and Strategies: A Short Introduction

    Science.gov (United States)

    Liu, Feng

    2010-01-01

    This paper gives a short analysis of reading abilities and reading strategies. Much research has been done to investigate the nature of reading, though it's had to exactly define reading abilities and strategies. Different kinds of readings are discussed in this paper and distinctions are made between first language reading and second or foreign…

  6. Thermoelectric neutron dosimetry: a short introduction

    International Nuclear Information System (INIS)

    Mathieu, F.; Meier, R.; Debrue, J.; Leonard, F.; Schubert, W.

    1977-01-01

    The paper gives a short introduction and state-of-the-art account of an unconventional, non destructive neutron dosimetry method based on monitoring the neutron fluence dependent changes of the thermoelectric properties of base metals and alloys. The basic principles are exposed and illustrated with experimental data obtained during an exploratory irradiation in the BR2 reactor

  7. Textbook Error: Short Circuiting on Electrochemical Cell

    Science.gov (United States)

    Bonicamp, Judith M.; Clark, Roy W.

    2007-01-01

    Short circuiting an electrochemical cell is an unreported but persistent error in the electrochemistry textbooks. It is suggested that diagrams depicting a cell delivering usable current to a load be postponed, the theory of open-circuit galvanic cells is explained, the voltages from the tables of standard reduction potentials is calculated and…

  8. A Long Look at the Short Film

    Science.gov (United States)

    Miller, Franklin, Jr.

    1971-01-01

    The history of the short film and the single concept film loop is presented. Lists fourteen reasons why it may be necessary to make and use a film loop. Film loop projectors are analyzed according to present features and deficiencies with predictions on future improvements. (DS)

  9. Short range order of selenite glasses

    Czech Academy of Sciences Publication Activity Database

    Neov, S.; Gerasimova, I.; Yordanov, S.; Lakov, L.; Mikula, Pavol; Lukáš, Petr

    1999-01-01

    Roč. 40, č. 2 (1999), s. 111-112 ISSN 0031-9090 R&D Projects: GA AV ČR KSK1010104 Keywords : short range * selenite glasses Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.822, year: 1999

  10. Asian Short Fiction. Asian Studies Instructional Module.

    Science.gov (United States)

    Waugh, Susan

    This curriculum outline introduces the components of a course which explores the genre of short novels, including works by twentieth-century Japanese and Chinese authors. First, the catalogue course description and required texts are presented, highlighting the instructor's historical introduction to the development of Western, Japanese, and…

  11. Short GRB afterglows observed with GROND

    DEFF Research Database (Denmark)

    Nicuesa Guelbenzu, A.; Klose, S.; Rossi, A.

    2013-01-01

    We report on follow-up observations of 20 short-duration gamma-ray bursts (T90 < 2s) performed in g′r′i′z′JHK s with the Gamma-Ray Burst Optical Near-Infrared Detector (GROND) between mid-2007 and the end of 2010. This is the most homogeneous and comprehensive data set on GRB afterglow observatio...

  12. SHORT COMMUNICATION High prevalence of Plasmodium ...

    African Journals Online (AJOL)

    Dell

    Volume 20, Number 1, January 2018. 1. SHORT COMMUNICATION ... This study was designed to establish the prevalence of Plasmodium falciparum malaria among HIV infected populations. ... The prevalence of P. falciparum was high among HIV seropositive individuals in the Lake Victoria Zone, which calls for additional ...

  13. Teaching Hemingway's "The Short Happy Life."

    Science.gov (United States)

    Stacy, Gerald

    2000-01-01

    Considers many ways to teach Hemingway's "The Short Happy Life of Francis Macomber." Explores the ironic implications of Macomber's experience and compares it with the experience of Sammy in another initiation story, John Updike's "A&P." Describes how he leads the discussion about this story, and ends the discussion by…

  14. SHORT COMMUNICATION CONVENIENT AND MILD SYNTHESIS ...

    African Journals Online (AJOL)

    Preferred Customer

    *Corresponding author. E-mail: naeimi@kashanu.ac.ir. SHORT COMMUNICATION. CONVENIENT AND MILD SYNTHESIS AND CHARACTERISATION OF. SOME NEW SCHIFF BASES. Hossein Naeimi* and Zahra Sadat Nazifi. Department of Organic Chemistry, Faculty of Chemistry, University of Kashan,. Kashan, 87317 ...

  15. Regional variation in short distance homogamy

    NARCIS (Netherlands)

    Haandrikman, K.; van Wissen, L.J.G.

    2011-01-01

    A third of all Dutch cohabiters choose a partner from the same municipality, so-called short distance homogamy. This article analyses the regional variation in this phenomenon, and it explains this variation in terms of geographical, socioeconomic, demographic and cultural determinants. Population

  16. Heterogeneity in Short Gamma-Ray Bursts

    Science.gov (United States)

    Norris, Jay P.; Gehrels Neil; Scargle, Jeffrey D.

    2011-01-01

    We analyze the Swift/BAT sample of short gamma-ray bursts, using an objective Bayesian Block procedure to extract temporal descriptors of the bursts' initial pulse complexes (IPCs). The sample comprises 12 and 41 bursts with and without extended emission (EE) components, respectively. IPCs of non-EE bursts are dominated by single pulse structures, while EE bursts tend to have two or more pulse structures. The medians of characteristic timescales - durations, pulse structure widths, and peak intervals - for EE bursts are factors of approx 2-3 longer than for non-EE bursts. A trend previously reported by Hakkila and colleagues unifying long and short bursts - the anti-correlation of pulse intensity and width - continues in the two short burst groups, with non-EE bursts extending to more intense, narrower pulses. In addition we find that preceding and succeeding pulse intensities are anti-correlated with pulse interval. We also examine the short burst X-ray afterglows as observed by the Swift/XRT. The median flux of the initial XRT detections for EE bursts (approx 6 X 10(exp -10) erg / sq cm/ s) is approx > 20 x brighter than for non-EE bursts, and the median X-ray afterglow duration for EE bursts (approx 60,000 s) is approx 30 x longer than for non-EE bursts. The tendency for EE bursts toward longer prompt-emission timescales and higher initial X-ray afterglow fluxes implies larger energy injections powering the afterglows. The longer-lasting X-ray afterglows of EE bursts may suggest that a significant fraction explode into more dense environments than non-EE bursts, or that the sometimes-dominant EE component efficiently p()wers the afterglow. Combined, these results favor different progenitors for EE and non-EE short bursts.

  17. HETEROGENEITY IN SHORT GAMMA-RAY BURSTS

    International Nuclear Information System (INIS)

    Norris, Jay P.; Gehrels, Neil; Scargle, Jeffrey D.

    2011-01-01

    We analyze the Swift/BAT sample of short gamma-ray bursts, using an objective Bayesian Block procedure to extract temporal descriptors of the bursts' initial pulse complexes (IPCs). The sample is comprised of 12 and 41 bursts with and without extended emission (EE) components, respectively. IPCs of non-EE bursts are dominated by single pulse structures, while EE bursts tend to have two or more pulse structures. The medians of characteristic timescales-durations, pulse structure widths, and peak intervals-for EE bursts are factors of ∼2-3 longer than for non-EE bursts. A trend previously reported by Hakkila and colleagues unifying long and short bursts-the anti-correlation of pulse intensity and width-continues in the two short burst groups, with non-EE bursts extending to more intense, narrower pulses. In addition, we find that preceding and succeeding pulse intensities are anti-correlated with pulse interval. We also examine the short burst X-ray afterglows as observed by the Swift/X-Ray Telescope (XRT). The median flux of the initial XRT detections for EE bursts (∼6x10 -10 erg cm -2 s -1 ) is ∼>20x brighter than for non-EE bursts, and the median X-ray afterglow duration for EE bursts (∼60,000 s) is ∼30x longer than for non-EE bursts. The tendency for EE bursts toward longer prompt-emission timescales and higher initial X-ray afterglow fluxes implies larger energy injections powering the afterglows. The longer-lasting X-ray afterglows of EE bursts may suggest that a significant fraction explode into denser environments than non-EE bursts, or that the sometimes-dominant EE component efficiently powers the afterglow. Combined, these results favor different progenitors for EE and non-EE short bursts.

  18. Etiology of short stature in children

    International Nuclear Information System (INIS)

    Sultan, M.; Afzal, M.; Ali, S.

    2008-01-01

    To determine the causes of short stature in children with special emphasis on growth hormone deficiency. Two hundred and fourteen children (140 boys and 74 girls), ranging from 02 to 15 years presenting with short stature were studied. Height and weight were plotted on appropriate growth charts and centiles determined. Relevant hematological and biochemical investigations including thyroid profile were done. Bone age was determined in all cases. Growth hormone axis was investigated after excluding other causes. Karyotyping was done in selected cases. Data was analyzed by SPSS 10.0 by descriptive statistics. Mean values were compared using t-test. In this study, the five most common etiological factors in order of frequency were Constitutional Growth Delay (CGD), Familial Short Stature (FSS), malnutrition, coeliac disease and Growth Hormone Deficiency (GHD). In 37.4% of patients, the study revealed normal variants of growth - CGD, FSS or combination of both, 46.7% cases had nonendocrinological and 15.9% had endocrinological etiology. CGD (22.1%) in males and FSS (27%) in females were the most common etiology. GHD was found in 6.1% children and it comprised 38.2% of all endocrinological causes. Children with height falling below 0.4th centile were more likely to have a pathological short stature (79.2%) compared to 39.3% whose height was below 3rd centile but above 0.4th centile (p<0.05). CGD and FSS are most common causes of short stature in boys and girls respectively, whereas, GHD is a relatively uncommon etiology. (author)

  19. Growing up with short stature : Psychosocial consequences of hormone treatment

    NARCIS (Netherlands)

    Visser-van Balen, J.

    2007-01-01

    Growing up with short stature. Psychosocial consequences of hormone treatment To enhance height in children with short stature, growth hormone (GH) can be used. In short children without a detectable pathology underlying their short stature, there is no medical rationale for growth hormone

  20. Short sales, differences of opinion and fundamental value

    NARCIS (Netherlands)

    Brounen, Dirk; Porras Prado, M.; Ling, D.C.

    2013-01-01

    This study explores the role of short sale constraints in explaining the variation in premiums to Net Asset Value (NAV) in REIT pricing. We use proprietary information on short sales between June 2006 and September 2008 to examine how short sales and short sale constraints affect the variation in

  1. Modular Short Form Videos for Library Instruction

    Directory of Open Access Journals (Sweden)

    Cindy Craig

    2017-10-01

    Full Text Available In Brief Expensive software isn’t necessary to create effective tutorials. Quick, unedited tutorials created on social media, such as on Instagram or Snapchat, may be more effective. These short form videos (SFVs combine the advantages of animated GIFs with the advantages of screencasts: modularity, repetition of steps, and animated visuals supported by pertinent audio. SFVs are cheap (or free and easy to make with materials libraries already possess, such as Internet access, computers, and smartphones. They are easily replaceable if the subject changes. The short form forces librarians to get right to the point. Finally, SFVs are easily disseminated on social media and have the potential to go viral.

  2. Field Optimization for short Period Undulators

    CERN Document Server

    Peiffer, P; Rossmanith, R; Schoerling, D

    2011-01-01

    Undulators dedicated to low energy electron beams, like Laser Wakefield Accelerators, require very short period lengths to achieve X-ray emission. However, at these short period length (LambdaU ~ 5 mm) it becomes difficult to reach magnetic field amplitudes that lead to a K parameter of >1, which is generally desired. Room temperature permanent magnets and even superconductive undulators using Nb-Ti as conductor material have proven insufficient to achieve the desired field amplitudes. The superconductor Nb$_{3}$Sn has the theoretical potential to achieve the desired fields. However, up to now it is limited by several technological challenges to much lower field values than theoretically predicted. An alternative idea for higher fields is to manufacture the poles of the undulator body from Holmium instead of iron or to use Nb-Ti wires with a higher superconductor/copper ratio. The advantages and challenges of the different options are compared in this contribution.

  3. Ultimately short ballistic vertical graphene Josephson junctions

    Science.gov (United States)

    Lee, Gil-Ho; Kim, Sol; Jhi, Seung-Hoon; Lee, Hu-Jong

    2015-01-01

    Much efforts have been made for the realization of hybrid Josephson junctions incorporating various materials for the fundamental studies of exotic physical phenomena as well as the applications to superconducting quantum devices. Nonetheless, the efforts have been hindered by the diffusive nature of the conducting channels and interfaces. To overcome the obstacles, we vertically sandwiched a cleaved graphene monoatomic layer as the normal-conducting spacer between superconducting electrodes. The atomically thin single-crystalline graphene layer serves as an ultimately short conducting channel, with highly transparent interfaces with superconductors. In particular, we show the strong Josephson coupling reaching the theoretical limit, the convex-shaped temperature dependence of the Josephson critical current and the exceptionally skewed phase dependence of the Josephson current; all demonstrate the bona fide short and ballistic Josephson nature. This vertical stacking scheme for extremely thin transparent spacers would open a new pathway for exploring the exotic coherence phenomena occurring on an atomic scale. PMID:25635386

  4. Integrable discretizations of the short pulse equation

    International Nuclear Information System (INIS)

    Feng Baofeng; Maruno, Ken-ichi; Ohta, Yasuhiro

    2010-01-01

    In this paper, we propose integrable semi-discrete and full-discrete analogues of the short pulse (SP) equation. The key construction is the bilinear form and determinant structure of solutions of the SP equation. We also give the determinant formulas of N-soliton solutions of the semi-discrete and full-discrete analogues of the SP equations, from which the multi-loop and multi-breather solutions can be generated. In the continuous limit, the full-discrete SP equation converges to the semi-discrete SP equation, and then to the continuous SP equation. Based on the semi-discrete SP equation, an integrable numerical scheme, i.e. a self-adaptive moving mesh scheme, is proposed and used for the numerical computation of the short pulse equation.

  5. Public perceptions of short rotation coppice

    International Nuclear Information System (INIS)

    Sadler, R.

    1993-01-01

    The ''Wood as a Fuel'' programme - which funded the research covered in this report - is one of the renewable energy development programmes managed by ETSU (the Energy Technology Support Unit) for the Department of Trade and Industry. This national programme is developing the production and use of fuel wood from two main sources - forestry residues and short rotation coppice. Wood fuel from short rotation coppice offers the greater potential - energy equivalent to 10 mtce (million tonnes of coal equivalent) could be produced annually from 1 million hectares of land. This programme is now well established, with ten trial coppice sites in operation, plus some 40 others. A number of successfully willow and poplar clones have been selected for different soil conditions, and machinery for planting and harvesting has been developed. Local consortia of farmers and users are being established to provide long-term markets for the wood fuel produced. (author)

  6. Lethal neonatal short-limbed dwarfism

    International Nuclear Information System (INIS)

    Kim, Ok Hwa; Yim, Chung Ik; Bahk, Yong Whee

    1986-01-01

    We have detailed our experiences on 6 cases of neonatal lethal short-limbed dwarfism and reviewed the articles. They include, achondrogenesis, thanatophoric dysplasia, asphyxiating thoracic dysplasia, osteogenesis imperfect a congenita, and hypophosphatasia lethals. Five babies were born alive but died soon after birth and one was a stillbirth. The main cause of failure to thrive was respiratory insufficiency. Each case was having quite characteristic radiologic findings, even if the general appearances were similar to the achondroplasts clinically. Precise diagnosis is very important for genetic counselling of the parents and alarm to them the possibility of bone dysplasias to the next offsprings. For this purpose, the radiologists play major role for the correct diagnosis. We stress that when the baby is born with short-limbed dwarfism, whole body radiogram should be taken including lateral view and postmortem radiogram is also very precious.

  7. Lethal neonatal short-limbed dwarfism

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ok Hwa; Yim, Chung Ik; Bahk, Yong Whee [Catholic Medical College, Seoul (Korea, Republic of)

    1986-02-15

    We have detailed our experiences on 6 cases of neonatal lethal short-limbed dwarfism and reviewed the articles. They include, achondrogenesis, thanatophoric dysplasia, asphyxiating thoracic dysplasia, osteogenesis imperfect a congenita, and hypophosphatasia lethals. Five babies were born alive but died soon after birth and one was a stillbirth. The main cause of failure to thrive was respiratory insufficiency. Each case was having quite characteristic radiologic findings, even if the general appearances were similar to the achondroplasts clinically. Precise diagnosis is very important for genetic counselling of the parents and alarm to them the possibility of bone dysplasias to the next offsprings. For this purpose, the radiologists play major role for the correct diagnosis. We stress that when the baby is born with short-limbed dwarfism, whole body radiogram should be taken including lateral view and postmortem radiogram is also very precious.

  8. Familial short fifth metacarpals and insulin resistance

    International Nuclear Information System (INIS)

    Hyari, Muwafag; Hamamy, Hanan; Barham, Muries; Ajlouni, Kamel; Al-Hadidy, Azmy

    2006-01-01

    Very few reports on the phenotype of short fifth metacarpals have been published in the medical literature. We report a Jordanian family in which three sisters aged 15, 13 and 8 years revealed bilateral shortening of the fifth fingers and radiological shortening of the fifth metacarpals. The father had unilateral short fifth metacarpal. The elder two sisters, their father as well as their brother and another sister manifested insulin resistance. Spherocytosis was diagnosed in one of the girls and her father. The parents are non-consanguineous. This constellation of findings has not been previously reported and could point to the presence of two disorders segregating in the family or to a novel syndrome with autosomal dominant inheritance and variable expressivity. (orig.)

  9. Ultra-Wideband, Short Pulse Electromagnetics 9

    CERN Document Server

    Rachidi, Farhad; Kaelin, Armin; Sabath, Frank; UWB SP 9

    2010-01-01

    Ultra-wideband (UWB), short-pulse (SP) electromagnetics are now being used for an increasingly wide variety of applications, including collision avoidance radar, concealed object detection, and communications. Notable progress in UWB and SP technologies has been achieved by investigations of their theoretical bases and improvements in solid-state manufacturing, computers, and digitizers. UWB radar systems are also being used for mine clearing, oil pipeline inspections, archeology, geology, and electronic effects testing. Ultra-wideband Short-Pulse Electromagnetics 9 presents selected papers of deep technical content and high scientific quality from the UWB-SP9 Conference, which was held from July 21-25, 2008, in Lausanne, Switzerland. The wide-ranging coverage includes contributions on electromagnetic theory, time-domain computational techniques, modeling, antennas, pulsed-power, UWB interactions, radar systems, UWB communications, and broadband systems and components. This book serves as a state-of-the-art r...

  10. Magnetic short-range order in Gd

    International Nuclear Information System (INIS)

    Child, H.R.

    1978-01-01

    The magnetic short-range order in a ferromagnetic, isotopically enriched 160 Gd metal single crystal has been investigated by quasielastic scattering of 81-meV neutrons. Since Gd behaves as an S-state ion in the metal, little anisotropy is expected in its magnetic behavior. However, the data show that there is anisotropic short-range order present over a large temperature interval both above and below T/sub C/. The data have been analyzed in terms of an Ornstein-Zernike Lorentzian form with anisotropic correlation ranges. These correlation ranges as deduced from the observed data behave normally above T/sub C/ but seem to remain constant over a fairly large interval below T/sub C/ before becoming unobservable at lower temperatures. These observations suggest that the magnetic ordering in Gd may be a more complicated phenomenon than first believed

  11. A short proof of increased parabolic regularity

    Directory of Open Access Journals (Sweden)

    Stephen Pankavich

    2015-08-01

    Full Text Available We present a short proof of the increased regularity obtained by solutions to uniformly parabolic partial differential equations. Though this setting is fairly introductory, our new method of proof, which uses a priori estimates and an inductive method, can be extended to prove analogous results for problems with time-dependent coefficients, advection-diffusion or reaction diffusion equations, and nonlinear PDEs even when other tools, such as semigroup methods or the use of explicit fundamental solutions, are unavailable.

  12. Long life of a short film.

    Science.gov (United States)

    Wadia, R V

    2000-01-01

    What follows is an account of my personal experiences as an independent Indian film director who had the fortune to make the country's first openly gay film, the short BOMgAY That said, I would like this essay to be accepted as, rather than a critical appraisal of Indian cinema, a humbly autobiographical account of one individual caught in the hectic throes of political (and cinematic) visibility.

  13. Molecular beam epitaxy a short history

    CERN Document Server

    Orton, J W

    2015-01-01

    This volume describes the development of molecular beam epitaxy from its origins in the 1960s through to the present day. It begins with a short historical account of other methods of crystal growth, both bulk and epitaxial, to set the subject in context, emphasising the wide range of semiconductor materials employed. This is followed by an introduction to molecular beams and their use in the Stern-Gerlach experiment and the development of the microwave MASER.

  14. Automatic location of short circuit faults

    Energy Technology Data Exchange (ETDEWEB)

    Lehtonen, M. [VTT Energy, Espoo (Finland); Hakola, T.; Antila, E. [ABB Power Oy, Helsinki (Finland); Seppaenen, M. [North-Carelian Power Company (Finland)

    1996-12-31

    In this presentation, the automatic location of short circuit faults on medium voltage distribution lines, based on the integration of computer systems of medium voltage distribution network automation is discussed. First the distribution data management systems and their interface with the substation telecontrol, or SCADA systems, is studied. Then the integration of substation telecontrol system and computerised relay protection is discussed. Finally, the implementation of the fault location system is presented and the practical experience with the system is discussed

  15. Short-term Memory of Deep RNN

    OpenAIRE

    Gallicchio, Claudio

    2018-01-01

    The extension of deep learning towards temporal data processing is gaining an increasing research interest. In this paper we investigate the properties of state dynamics developed in successive levels of deep recurrent neural networks (RNNs) in terms of short-term memory abilities. Our results reveal interesting insights that shed light on the nature of layering as a factor of RNN design. Noticeably, higher layers in a hierarchically organized RNN architecture results to be inherently biased ...

  16. Pulse pile-up. I: Short pulses

    International Nuclear Information System (INIS)

    Wilkinson, D.H.

    1990-07-01

    The search for rare large pulses against an intense background of smaller ones involves consideration of pulse pile-up. Approximate methods are presented, based on ruin theory, by which the probability of such pile-up may be estimated for pulses of arbitrary form and of arbitrary pulse-height distribution. These methods are checked against cases for which exact solutions are available. The present paper is concerned chiefly with short pulses of finite total duration. (Author) (5 refs., 24 figs.)

  17. Optical Detection in Ultrafast Short Wavelength Science

    International Nuclear Information System (INIS)

    Fullagar, Wilfred K.; Hall, Chris J.

    2010-01-01

    A new approach to coherent detection of ionising radiation is briefly motivated and recounted. The approach involves optical scattering of coherent light fields by colour centres in transparent solids. It has significant potential for diffractive imaging applications that require high detection dynamic range from pulsed high brilliance short wavelength sources. It also motivates new incarnations of Bragg's X-ray microscope for pump-probe studies of ultrafast molecular structure-dynamics.

  18. Southern hemisphere searches for short period pulsars

    International Nuclear Information System (INIS)

    Manchester, R.N.

    1984-01-01

    Two searches of the southern sky for short period pulsars are briefly described. The first, made using the 64-m telescope at Parkes, is sensitive to pulsars with periods greater than about 10 ms and the second, made using the Molonglo radio telescope, has sensitivity down to periods of about 1.5 ms. Four pulsars were found in the Parkes survey and none in the Molonglo survey, although analysis of the latter is as yet incomplete. 10 references, 1 figure, 2 tables

  19. Short wavelength striations on expanding plasma clouds

    International Nuclear Information System (INIS)

    Winske, D.; Gary, S.P.

    1989-01-01

    The growth and evolution of short wavelength (< ion gyroradius) flute modes on a plasma expanding across an ambient magnetic field have been actively studied in recent years, both by means of experiments in the laboratory as well as in space and through numerical simulations. We review the relevant observations and simulations results, discuss the instability mechanism and related linear theory, and describe recent work to bring experiments and theory into better agreement. 30 refs., 6 figs

  20. Automatic location of short circuit faults

    Energy Technology Data Exchange (ETDEWEB)

    Lehtonen, M [VTT Energy, Espoo (Finland); Hakola, T; Antila, E [ABB Power Oy (Finland); Seppaenen, M [North-Carelian Power Company (Finland)

    1998-08-01

    In this chapter, the automatic location of short circuit faults on medium voltage distribution lines, based on the integration of computer systems of medium voltage distribution network automation is discussed. First the distribution data management systems and their interface with the substation telecontrol, or SCADA systems, is studied. Then the integration of substation telecontrol system and computerized relay protection is discussed. Finally, the implementation of the fault location system is presented and the practical experience with the system is discussed

  1. Short-term LNG-markets

    International Nuclear Information System (INIS)

    Eldegard, Tom; Lund, Arne-Christian; Miltersen, Kristian; Rud, Linda

    2005-01-01

    The global Liquefied Natural Gas (LNG) industry has experienced substantial growth in the past decades. In the traditional trade patterns of LNG the product has typically been handled within a dedicated chain of plants and vessels fully committed by long term contracts or common ownership, providing risk sharing of large investments in a non-liquid market. Increasing gas prices and substantial cost reductions in all parts of the LNG chain have made LNG projects viable even if only part of the capacity is secured by long-term contracts, opening for more flexible trade of the remainder. Increasing gas demand, especially in power generation, combined with cost reductions in the cost of LNG terminals, open new markets for LNG. For the LNG supplier, the flexibility of shifting volumes between regions represents an additional value. International trade in LNG has been increasing, now accounting for more than one fifth of the world's cross-border gas trade. Despite traditional vertical chain bonds, increased flexibility has contributed in fact to an increasing LNG spot trade, representing 8% of global trade in 2002. The focus of this paper is on the development of global short-term LNG markets, and their role with respect to efficiency and security of supply in European gas markets. Arbitrage opportunities arising from price differences between regional markets (such as North America versus Europe) are important impetuses for flexible short-term trade. However, the short-term LNG trade may suffer from problems related to market access, e.g. limited access to terminals and regulatory issues, as well as rigidities connected to vertical binding within the LNG chain. Important issues related to the role of short-term LNG-trade in the European gas market are: Competition, flexibility in meeting peak demand, security of supply and consequences of differences in pricing policies (oil-linked prices in Europe and spot market prices in North America). (Author)

  2. Mechanised harvesting of short-rotation coppices

    OpenAIRE

    Vanbeveren, Stefan P.P.; Spinelli, Raffaele; Eisenbies, Mark; Schweier, Janine; Mola-Yudego, Blas; Magagnotti, Natascia; Acuna, Mauricio; Dimitriou, Ioannis; Ceulemans, Reinhart

    2017-01-01

    Abstract: Short-rotation coppice (SRC) is an important source of woody biomass for bioenergy. Despite the research carried out on several aspects of SRC production, many uncertainties create barriers to farmers establishing SRC plantations. One of the key economic sources of uncertainty is harvesting methods and costs; more specifically, the performance of contemporary machine methods is reviewed. We collected data from 25 literature references, describing 166 field trials. Three harvesting s...

  3. Brownian motion in short range random potentials

    International Nuclear Information System (INIS)

    Romero, A.H.; Romero, A.H.; Sancho, J.M.

    1998-01-01

    A numerical study of Brownian motion of noninteracting particles in random potentials is presented. The dynamics are modeled by Langevin equations in the high friction limit. The random potentials are Gaussian distributed and short ranged. The simulations are performed in one and two dimensions. Different dynamical regimes are found and explained. Effective subdiffusive exponents are obtained and commented on. copyright 1998 The American Physical Society

  4. Hedge Ratios for short and leveraged ETFs

    Directory of Open Access Journals (Sweden)

    Leo Schubert

    2011-06-01

    Full Text Available Exchange Traded Funds (ETFs exist for stock-, bond- and commodity markets. In most cases the underlying of an ETF is an index. Fund management today uses the active and passive way to construct a portfolio. ETFs can be used for passive portfolio management. Then ETFs with positive leverage factors are preferred. In the frame of active portfolio also the ETFs with negative leverage factors can be applied for the hedge or cross hedge of a portfolio. These hedging possibilities will be analyzed in this paper. Short ETFs exist with different leverage factors. In Europe, the leverage factors 1 (e.g. ShortDAX ETF and 2 (e.g. DJ STOXX 600 Double Short are offered while in the financial markets of the United States factors from 1 to 4 can be found. To investigate the effect of the different leverage factors and other parameters Monte Carlo Simulation was used. The results show e.g. that higher leverage factors achieve higher profits as well as losses. In the case, that a bearish market is supposed, minimizing the variance of the hedge seem not to be until to get better hedging results, due to a very skewed return distribution of the hedge. The risk measure target-shortfall-probability confirms the use of the standard hedge weightings which depend only on the leverage factor. This characteristic remains, when a portfolio has to be hedged instead of the underlying index of the short ETF. For portfolios which have a low correlation with the index return should not be used high leverage factors for hedging, due to the higher volatility and target-shortfall-probability.

  5. A short-term neural network memory

    Energy Technology Data Exchange (ETDEWEB)

    Morris, R.J.T.; Wong, W.S.

    1988-12-01

    Neural network memories with storage prescriptions based on Hebb's rule are known to collapse as more words are stored. By requiring that the most recently stored word be remembered precisely, a new simple short-term neutral network memory is obtained and its steady state capacity analyzed and simulated. Comparisons are drawn with Hopfield's method, the delta method of Widrow and Hoff, and the revised marginalist model of Mezard, Nadal, and Toulouse.

  6. Automatic location of short circuit faults

    Energy Technology Data Exchange (ETDEWEB)

    Lehtonen, M [VTT Energy, Espoo (Finland); Hakola, T; Antila, E [ABB Power Oy, Helsinki (Finland); Seppaenen, M [North-Carelian Power Company (Finland)

    1997-12-31

    In this presentation, the automatic location of short circuit faults on medium voltage distribution lines, based on the integration of computer systems of medium voltage distribution network automation is discussed. First the distribution data management systems and their interface with the substation telecontrol, or SCADA systems, is studied. Then the integration of substation telecontrol system and computerised relay protection is discussed. Finally, the implementation of the fault location system is presented and the practical experience with the system is discussed

  7. A short course in sustainable product development

    DEFF Research Database (Denmark)

    McAloone, Tim C.

    2005-01-01

    This short course in sustainable product development models, methods and mindsets is designed to fit into the Unical course on Engineering Design Methods. Three modules (called “seminars”) will guide you through . The demands for sustainable development . Professional methods for analysing and ch...... and changing products’ environmental profiles . A new approach to product service system development, where the physical product becomes an incidental aspect in the final offering to the customer...

  8. Short term depression unmasks the ghost frequency.

    Directory of Open Access Journals (Sweden)

    Tjeerd V Olde Scheper

    Full Text Available Short Term Plasticity (STP has been shown to exist extensively in synapses throughout the brain. Its function is more or less clear in the sense that it alters the probability of synaptic transmission at short time scales. However, it is still unclear what effect STP has on the dynamics of neural networks. We show, using a novel dynamic STP model, that Short Term Depression (STD can affect the phase of frequency coded input such that small networks can perform temporal signal summation and determination with high accuracy. We show that this property of STD can readily solve the problem of the ghost frequency, the perceived pitch of a harmonic complex in absence of the base frequency. Additionally, we demonstrate that this property can explain dynamics in larger networks. By means of two models, one of chopper neurons in the Ventral Cochlear Nucleus and one of a cortical microcircuit with inhibitory Martinotti neurons, it is shown that the dynamics in these microcircuits can reliably be reproduced using STP. Our model of STP gives important insights into the potential roles of STP in self-regulation of cortical activity and long-range afferent input in neuronal microcircuits.

  9. Ultra-short silicon MMI duplexer

    Science.gov (United States)

    Yi, Huaxiang; Huang, Yawen; Wang, Xingjun; Zhou, Zhiping

    2012-11-01

    The fiber-to-the-home (FTTH) systems are growing fast these days, where two different wavelengths are used for upstream and downstream traffic, typically 1310nm and 1490nm. The duplexers are the key elements to separate these wavelengths into different path in central offices (CO) and optical network unit (ONU) in passive optical network (PON). Multimode interference (MMI) has some benefits to be a duplexer including large fabrication tolerance, low-temperature dependence, and low-polarization dependence, but its size is too large to integrate in conventional case. Based on the silicon photonics platform, ultra-short silicon MMI duplexer was demonstrated to separate the 1310nm and 1490nm lights. By studying the theory of self-image phenomena in MMI, the first order images are adopted in order to keep the device short. A cascaded MMI structure was investigated to implement the wavelength splitting, where both the light of 1310nm and 1490nm was input from the same port, and the 1490nm light was coupling cross the first MMI and output at the cross-port in the device while the 1310nm light was coupling through the first and second MMI and output at the bar-port in the device. The experiment was carried on with the SOI wafer of 340nm top silicon. The cascaded MMI was investigated to fold the length of the duplexer as short as 117μm with the extinct ratio over 10dB.

  10. The Long and the Short of It

    Science.gov (United States)

    2006-01-01

    Gamma-Ray bursts, the extreme explosions that mark the birth of black holes, come in two flavors, long bursts lasting a few seconds or more, and short bursts lasting for less than a second. The mechanisms giving rise to these two types of bursts were, for a long time, unknown to astronomers. But a series of breakthroughs starting with BeppoSAX, HETE, and Swift gave astronomers some clues and confidence about the nature of long and short bursts. Long bursts mark the collapse of a young, extremely massive star into a black hole; short bursts mark the formation of a black hole by a merger of neutron stars (or perhaps a neutron star with a black hole to form a larger black hole). But a new observation has clouded this clear dichotomy. The picture above is an X-ray image of a gamma-ray burst, GRB 060614, taken by Swift's X-ray Telescope. This burst lasted more than 100 seconds, clearly showing that it's a long burst. But follow-up observations of the burst did not show the tell-tale signatures of a supernova explosion which should be produced by the collapse of a large star. Furthermore this burst occurred in a galaxy which has very few extremely massive stars. Does this hybrid burst represent an entirely new mechanism behind these titanic explosions? The hunt is on.

  11. Short-film Festival at the Globe

    CERN Multimedia

    2007-01-01

    Get out your diaries and prepare to be star-struck as the Globe of Science and Innovation meets the silver screen! The CERN "Open Your Eyes Films" film-making club is organising a festival of short films entitled CinéGlobe from Thursday 8 to Saturday 10 November. On the Thursday and Friday, you’ll be able to watch 47 short films free of charge in the Globe of Science and Innovation at various times of the day. The short films to be screened come from 21 different countries and have been selected from among 1400 entrees! All film genres will be represented : comedy, drama, animation, documentaries, experimental films, etc. Members of the public will even be able to vote for their favourite film: the audience’s favourite will be awarded a "Coup de coeur" award. An awards ceremony to honour the films that have received most votes will be held on Friday evening in the Globe of Science and Innovation. The Golden CinéGlobe for bes...

  12. Modeling Timbre Similarity of Short Music Clips.

    Science.gov (United States)

    Siedenburg, Kai; Müllensiefen, Daniel

    2017-01-01

    There is evidence from a number of recent studies that most listeners are able to extract information related to song identity, emotion, or genre from music excerpts with durations in the range of tenths of seconds. Because of these very short durations, timbre as a multifaceted auditory attribute appears as a plausible candidate for the type of features that listeners make use of when processing short music excerpts. However, the importance of timbre in listening tasks that involve short excerpts has not yet been demonstrated empirically. Hence, the goal of this study was to develop a method that allows to explore to what degree similarity judgments of short music clips can be modeled with low-level acoustic features related to timbre. We utilized the similarity data from two large samples of participants: Sample I was obtained via an online survey, used 16 clips of 400 ms length, and contained responses of 137,339 participants. Sample II was collected in a lab environment, used 16 clips of 800 ms length, and contained responses from 648 participants. Our model used two sets of audio features which included commonly used timbre descriptors and the well-known Mel-frequency cepstral coefficients as well as their temporal derivates. In order to predict pairwise similarities, the resulting distances between clips in terms of their audio features were used as predictor variables with partial least-squares regression. We found that a sparse selection of three to seven features from both descriptor sets-mainly encoding the coarse shape of the spectrum as well as spectrotemporal variability-best predicted similarities across the two sets of sounds. Notably, the inclusion of non-acoustic predictors of musical genre and record release date allowed much better generalization performance and explained up to 50% of shared variance ( R 2 ) between observations and model predictions. Overall, the results of this study empirically demonstrate that both acoustic features related

  13. Are short implants in the mandible safe?

    Directory of Open Access Journals (Sweden)

    Sergio Henrique Gonçalves Motta

    2009-10-01

    Full Text Available Objective: To analyze the importance of bioengineering and the improvement in surgical techniques demonstrated by the rates attained of the prevalence of successful placement of dental implants in the posterior region of the mandible, in D3 bone quality in patients between the ages of 52 and 60 years, with dentures fixed on 8.5 mm implants. Methods: The statistical data for this retrospective study were collected at the Post-Graduation Center of the Integrated Dentistry Center, Faculty of Sarandi / Academy of Dentistry - Rio de Janeiro, at the CLIVO clinic, from among a total of 2.294 implants placed in the mandible, in the period from 1999 to 2007. There was a total of 1.056 short implants, of a length shorter than or equal to 10 mm, among which 20 implants were randomly chosen and analyzed. Results: The data were treated statistically and comparison of these data was consubstantiated in constructive data analysis by means of Statistical Pattern Recognition Methods for each variable under study. A success rate of 85% was obtained, and the need to take certain care when indicating the use of short implants was verified. Conclusion: Bioengineering and the development of present day surgical techniques have optimized the use of short implants, with the aim of avoiding advanced surgeries. To compensate the smaller size, there are some factors that must be observed, such as: Bone quality, crown/implant ratio, number and diameter of implants, macroscopic and microscopic geometry of the implants, magnitude of mesial occlusal forces.

  14. A short textbook of colloid chemistry

    CERN Document Server

    Jirgensons, B

    1962-01-01

    A Short Textbook of Colloid Chemistry, Second Revised Edition details the factual aspect of colloid chemistry that includes the basic facts, established empirical and mathematical relationships, and practical applications. The chapters of the title are organized into two parts. In the first part, the text discusses the general concepts of colloid chemistry, such as the history and scope, basic terms, and basic methods in experiment with colloids. Part Two covers the technical aspect of colloid chemistry, such as the optical properties, electrical properties, and viscosity. The book will be of

  15. Monitoring method of short-emitters

    International Nuclear Information System (INIS)

    Gasanov, R.A.

    2013-01-01

    Radioprospecting is the initial stage of radioelectronic warfare and its main purpose is destination of the radio signal, determination of its parameters, to detect the content of broadcasts, as well as detection the locating of devices emitting radio signal. In all cases, the probability of signal interception is basically determined by the specified parameters of signals intelligence. The increase in speed is accompanied by a decrease in resolution and vice versa. This paper discusses the method of monitoring the short-term radio emissions, which adapts to the electromagnetic environment

  16. Short period tidal variations of earth rotation

    Science.gov (United States)

    Yoder, C. F.; Williams, J. G.; Parke, M. E.; Dickey, J. O.

    1981-01-01

    It is explained that the tidal deformation of the earth's polar moment of inertia by the moon and sun cause periodic variations in rotation. The short period oscillations give rise to a meter-sized, diurnal signature in the lunar laser ranging data obtained at McDonald Observatory. A solution is given for the scale parameter k/C at fortnightly and monthly tidal frequencies. The results are compared with those obtained by other investigators and with a theoretical estimate which includes the effect of oceans and a decoupled fluid core.

  17. Spectrum of short bowel syndrome in adults

    DEFF Research Database (Denmark)

    Jeppesen, Palle B

    2014-01-01

    to diminished health-related quality of life because of its many physical and psychological effects on patients. SBS is associated with decreased survival; risk factors for SBS-related mortality include very short remnant small bowel, end-jejunal remnant anatomy, and arterial mesenteric infarction as primary...... severity and resection type; thus, each patient should be individually managed. This review discusses the spectrum of disease in patients with SBS and presents common complications encountered by these patients to highlight the importance of individualized management and treatment....

  18. Longitudinal Diagnostics for Short Electron Beam Bunches

    Energy Technology Data Exchange (ETDEWEB)

    Loos, H.; /SLAC

    2010-06-11

    Single-pass free electron lasers require high peak currents from ultra-short electron bunches to reach saturation and an accurate measurement of bunch length and longitudinal bunch profile is necessary to control the bunch compression process from low to high beam energy. The various state-of-the-art diagnostics methods from ps to fs time scales using coherent radiation detection, RF deflection, and other techniques are presented. The use of linear accelerators as drivers for free electron lasers (FEL) and the advent of single-pass (SASE) FELs has driven the development of a wide range of diagnostic techniques for measuring the length and longitudinal distribution of short and ultra-short electron bunches. For SASE FELs the radiation power and the length of the undulator needed to achieve saturation depend strongly on the charge density of the electron beam. In the case of X-ray FELs, this requires the accelerator to produce ultra-high brightness beams with micron size transverse normalized emittances and peak currents of several kA through several stages of magnetic bunch compression. Different longitudinal diagnostics are employed to measure the peak current and bunch profile along these stages. The measurement techniques can be distinguished into different classes. Coherent methods detect the light emitted from the beam by some coherent radiation process (spectroscopic measurement), or directly measure the Coulomb field traveling with the beam (electro-optic). Phase space manipulation techniques map the time coordinate onto a transverse dimension and then use conventional transverse beam diagnostics (transverse deflector, rf zero-phasing). Further methods measure the profile or duration of an incoherent light pulse emitted by the bunch at wavelengths much shorted than the bunch length (streak camera, fluctuation technique) or modulate the electron beam at an optical wavelength and then generate a narrow bandwidth radiation pulse with the longitudinal profile of

  19. Black holes a very short introduction

    CERN Document Server

    Blundell, Katherine

    2015-01-01

    Black holes are a constant source of fascination to many due to their mysterious nature. Black Holes: A Very Short Introduction addresses a variety of questions, including what a black hole actually is, how they are characterized and discovered, and what would happen if you came too close to one. It explains how black holes form and grow—by stealing material that belongs to stars—as well as how many there may be in the Universe. It also explores the large black holes found in the centres of galaxies, and how black holes power quasars and lie behind other spectacular phenomena in the cosmos.

  20. Short radiological emergency response training program

    International Nuclear Information System (INIS)

    Williams, R.D.; Greenhouse, N.A.

    1977-01-01

    This paper presents an outline of a radiological emergency response training program conducted at Brookhaven National Laboratory by the health physics and safety training staff. This course is given to groups from local, county, state, and federal agencies and industrial organizations. It is normally three days in length, although the structure is flexible to accommodate individual needs and prior training. An important feature of the course is an emergency exercise utilizing a short lived radionuclide to better simulate real accident conditions. Groups are encouraged to use their own instruments to gain better familiarity with their operating characteristics under field conditions. Immediately following the exercise, a critical review of the students' performance is conducted

  1. The Reformation: A Very Short Introduction

    OpenAIRE

    TKACHENKO, Rostislav

    2017-01-01

    A small, relatively recent, and well-written book by Peter Marshall belongs tothe well-known Oxford series called “Very Short Introductions.” It is an informativeand analytical introduction to the history, culture, politics, and theology of theReformation that took place in sixteenth-century Europe. The Reformation is anacademic research-based book that is nevertheless very accessible to a wide audience. It is part of the larger company of historical and cultural mini-handbooks such as, The M...

  2. Antimalarial Activity of Ultra-Short Peptides

    Directory of Open Access Journals (Sweden)

    María Yolanda Rios

    2009-12-01

    Full Text Available Ultra-short peptides 1-9 were designed and synthesized with phenylalanine, ornithine and proline amino acid residues and their effect on antimalarial activity was analyzed. On the basis of the IC50 data for these compounds, the effects of nature, polarity, and amino acid sequence on Plasmodium berghei schizont cultures were analyzed too. Tetrapeptides Phe-Orn-Phe-Orn (4 and Lys-Phe-Phe-Orn (5 showed a very important activity with IC50 values of 3.31 and 2.57 μM, respectively. These two tetrapeptides are candidates for subsequent in vivo assays and SARS investigations.

  3. Implementation of short-term prediction

    Energy Technology Data Exchange (ETDEWEB)

    Landberg, L; Joensen, A; Giebel, G [and others

    1999-03-01

    This paper will giver a general overview of the results from a EU JOULE funded project (`Implementing short-term prediction at utilities`, JOR3-CT95-0008). Reference will be given to specialised papers where applicable. The goal of the project was to implement wind farm power output prediction systems in operational environments at a number of utilities in Europe. Two models were developed, one by Risoe and one by the Technical University of Denmark (DTU). Both prediction models used HIRLAM predictions from the Danish Meteorological Institute (DMI). (au) EFP-94; EU-JOULE. 11 refs.

  4. Neutrino physics with short baseline experiments

    International Nuclear Information System (INIS)

    Zimmerman, E.D.

    2006-01-01

    Neutrino physics with low- to medium-energy beams has progressed steadily over the last several years. Neutrino oscillation searches at short baseline (defined as 2 - -> 0.1eV 2 . One positive signal, from the LSND collaboration, exists and is being tested by the MiniBooNE experiment. Neutrino cross-section measurements are being made by MiniBooNE and K2K, which will be important for reducing systematic errors in present and future oscillation measurements. In the near future, dedicated cross- section experiments will begin operating at Fermilab. (author)

  5. Short-cavity squeezing in barium

    Science.gov (United States)

    Hope, D. M.; Bachor, H-A.; Manson, P. J.; Mcclelland, D. E.

    1992-01-01

    Broadband phase sensitive noise and squeezing were experimentally observed in a system of barium atoms interacting with a single mode of a short optical cavity. Squeezing of 13 +/- 3 percent was observed. A maximum possible squeezing of 45 +/- 8 percent could be inferred for out experimental conditions, after correction for measured loss factors. Noise reductions below the quantum limit were found over a range of detection frequencies 60-170 MHz and were best for high cavity transmission and large optical depths. The amount of squeezing observed is consistent with theoretical predictions from a full quantum statistical model of the system.

  6. Colliding droplets: a short film presentation

    International Nuclear Information System (INIS)

    Hendricks, C.D.

    1981-01-01

    A series of experiments were performed in which liquid droplets were caused to collide. Impact velocities to several meters per second and droplet diameters up to 600 micrometers were used. The impact parameters in the collisions vary from zero to greater than the sum of the droplet radii. Photographs of the collisions were taken with a high speed framing camera in order to study the impacts and subsequent behavior of the droplets. The experiments will be discussed and a short movie film presentation of some of the impacts will be shown

  7. Is visual short-term memory depthful?

    Science.gov (United States)

    Reeves, Adam; Lei, Quan

    2014-03-01

    Does visual short-term memory (VSTM) depend on depth, as it might be if information was stored in more than one depth layer? Depth is critical in natural viewing and might be expected to affect retention, but whether this is so is currently unknown. Cued partial reports of letter arrays (Sperling, 1960) were measured up to 700 ms after display termination. Adding stereoscopic depth hardly affected VSTM capacity or decay inferred from total errors. The pattern of transposition errors (letters reported from an uncued row) was almost independent of depth and cue delay. We conclude that VSTM is effectively two-dimensional. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. The short straight sections for the LHC

    International Nuclear Information System (INIS)

    Bergot, J.B.; Coussy, E.; Dambre, P.; Ollivier, Y.; Reynet, D.; Vincent, D.; Rohmig, P.

    1999-01-01

    In 1995 a close collaboration between CERN, CEA and CNRS has been established for the design, proto-typing and follow-up of industrial series production of a sub-assembly of the Large Hadron Collider (LHC). In this frame, the design office of IPN's Accelerator R and D group has in charge one of these contracts concerning the 386 Short Straight Sections (SSS) and particularly: - the cryostat design; - the study of procedures and tool assembly; - the construction of two prototypes during the year 1999; - the industrialization and the production follow-up for the series SSS. This collaboration will last until the year 2004. (authors)

  9. A short history of research on immunity to infectious diseases in fish

    NARCIS (Netherlands)

    Muiswinkel, van W.B.; Nakao, M.

    2014-01-01

    This review describes the history of research on immunity to infectious diseases of fish in the period between 1965 and today. Special attention is paid to those studies, which are dealing with the interaction between immune system and invading pathogens in bony fish. Moreover, additional biographic

  10. Development of a local baiting system for the control of the Africa invader fly, (Bactrocera invadens) Drew, Tsuruta and White (Diptera: Tephritidae) in mango orchards at Somanya, Eastern Ghana

    International Nuclear Information System (INIS)

    Yeboah, S.

    2012-01-01

    Fruit production plays an important role in Africa's economy. In Ghana, mango is targeted as one of the next non-traditional export crop that is expected to fetch the highest foreign exchange for the country and replace cocoa. Ghana's current production is said to have increased from 6,800 tonnes in 2007 to about 7000 tonnes in 2010. However, the African invader fruit fly, Bactrocera invadens, is causing high yield losses as an important quarantine pest and has brought some setback in the mango trade between Ghana and their exporting destinations. Imported commercial protein hydrolysate bait for controlling the flies constitutes the highest cost component of the control programme, excluding cost of labour. The baits are exhorbitant for local farmers and seldom available. This setback has called for the need to design and implement efficient and cost-effective control regimes for managing this pest. The objective of the study was to explore the development of locally produced, cheap and efficient baiting system using brewery yeast wastes and coloured cylinder traps to attract and control this quarantine pest. A 1 ha study area was selected within DORMEHSCO FARM, a mango orchard at Somanya in the Eastern region of Ghana with the Keith mango variety for the study. Local sources of Guiness, Beer and Pito yeast wastes were collected into Winchester bottles and subjected to pasteurisation. Papain enzyme was added to maximize yeast cell autolysis at 70 degrees celcius for 9 hours. The Micro-Kjeldahl apparatus was used to determine the percentage protein in each waste. Transparent cylinder traps with three different colours of lids (red, yellow and green) and three 3cm diameter round holes referred to as coloured traps were used to dispense the baits. The traps were labelled according to the type of bait and trap colour combination. The trials were conducted in two successive peak fruiting seasons fron October to November, 2011 (minor season and then from April to June

  11. Plat du jour – Short Films!

    CERN Multimedia

    Claudia Marcelloni

    2014-01-01

    Next week, take a break from the cafeteria and have a ciné-lunch at the Globe!   How about if, for a change, you forgot your lunch meeting and went to the movies with your colleagues (or that person that you always wanted to ask out) right here on the CERN site? CERN will be hosting the next CineGlobe International Film Festival from 18 to 23 March in the Globe of Science and Innovation, with the theme "Beyond the Frontier". The 4th annual festival will see 66 short films "inspired by science" in competition, including fiction films as well as documentaries. From Tuesday 18 to Friday 21, special lunch sessions will take place from 12.30 p.m. to 1.30 p.m. Food will be available for purchase at the “Café Cinéma” tent next to the Globe. Special evenings: While the short film screenings are the heart of the festival, each year CineGlobe also organises compelling special events every night, from feature fil...

  12. PTSD-8: A Short PTSD Inventory.

    Science.gov (United States)

    Hansen, Maj; Andersen, Tonny Elmose; Armour, Cherie; Elklit, Ask; Palic, Sabina; Mackrill, Thomas

    2010-09-28

    Traumatic events pose great challenges on mental health services in scarcity of specialist trauma clinicians and services. Simple short screening instruments for detecting adverse psychological responses are needed. Several brief screening instruments have been developed. However, some are limited, especially in relation to reflecting the posttraumatic stress disorder (PTSD) diagnosis. Recently, several studies have challenged pre-existing ideas about PTSD's latent structure. Factor analytic research currently supports two four factor models. One particular model contains a dysphoria factor which has been associated with depression and anxiety. The symptoms in this factor have been hailed as less specific to PTSD. The scope of this article is therefore to present a short screening instrument, based on this research; Posttraumatic Stress Disorder (PTSD) - 8 items. The PTSD-8 is shown to have good psychometric properties in three independent samples of whiplash patients (n=1710), rape victims (n=305), and disaster victims (n=516). Good test-rest reliability is also shown in a pilot study of young adults from families with alcohol problems (n=56).

  13. Capillary condensation of short-chain molecules.

    Science.gov (United States)

    Bryk, Paweł; Pizio, Orest; Sokolowski, Stefan

    2005-05-15

    A density-functional study of capillary condensation of fluids of short-chain molecules confined to slitlike pores is presented. The molecules are modeled as freely jointed tangent spherical segments with a hard core and with short-range attractive interaction between all the segments. We investigate how the critical parameters of capillary condensation of the fluid change when the pore width decreases and eventually becomes smaller than the nominal linear dimension of the single-chain molecule. We find that the dependence of critical parameters for a fluid of dimers and of tetramers on pore width is similar to that of the monomer fluid. On the other hand, for a fluid of chains consisting of a larger number of segments we observe an inversion effect. Namely, the critical temperature of capillary condensation decreases with increasing pore width for a certain interval of values of the pore width. This anomalous behavior is also influenced by the interaction between molecules and pore walls. We attribute this behavior to the effect of conformational changes of molecules upon confinement.

  14. Narrow resonances and short-range interactions

    International Nuclear Information System (INIS)

    Gelman, Boris A.

    2009-01-01

    Narrow resonances in systems with short-range interactions are discussed in an effective field theory (EFT) framework. An effective Lagrangian is formulated in the form of a combined expansion in powers of a momentum Q 0 | 0 --a resonance peak energy. At leading order in the combined expansion, a two-body scattering amplitude is the sum of a smooth background term of order Q 0 and a Breit-Wigner term of order Q 2 (δε) -1 which becomes dominant for δε 3 . Such an EFT is applicable to systems in which short-distance dynamics generates a low-lying quasistationary state. The EFT is generalized to describe a narrow low-lying resonance in a system of charged particles. It is shown that in the case of Coulomb repulsion, a two-body scattering amplitude at leading order in a combined expansion is the sum of a Coulomb-modified background term and a Breit-Wigner amplitude with parameters renormalized by Coulomb interactions.

  15. Short-Term Saved Leave Scheme

    CERN Multimedia

    2007-01-01

    As announced at the meeting of the Standing Concertation Committee (SCC) on 26 June 2007 and in http://Bulletin No. 28/2007, the existing Saved Leave Scheme will be discontinued as of 31 December 2007. Staff participating in the Scheme will shortly receive a contract amendment stipulating the end of financial contributions compensated by save leave. Leave already accumulated on saved leave accounts can continue to be taken in accordance with the rules applicable to the current scheme. A new system of saved leave will enter into force on 1 January 2008 and will be the subject of a new implementation procedure entitled "Short-term saved leave scheme" dated 1 January 2008. At its meeting on 4 December 2007, the SCC agreed to recommend the Director-General to approve this procedure, which can be consulted on the HR Department’s website at the following address: https://cern.ch/hr-services/services-Ben/sls_shortterm.asp All staff wishing to participate in the new scheme a...

  16. Short-Term Saved Leave Scheme

    CERN Multimedia

    HR Department

    2007-01-01

    As announced at the meeting of the Standing Concertation Committee (SCC) on 26 June 2007 and in http://Bulletin No. 28/2007, the existing Saved Leave Scheme will be discontinued as of 31 December 2007. Staff participating in the Scheme will shortly receive a contract amendment stipulating the end of financial contributions compensated by save leave. Leave already accumulated on saved leave accounts can continue to be taken in accordance with the rules applicable to the current scheme. A new system of saved leave will enter into force on 1 January 2008 and will be the subject of a new im-plementation procedure entitled "Short-term saved leave scheme" dated 1 January 2008. At its meeting on 4 December 2007, the SCC agreed to recommend the Director-General to approve this procedure, which can be consulted on the HR Department’s website at the following address: https://cern.ch/hr-services/services-Ben/sls_shortterm.asp All staff wishing to participate in the new scheme ...

  17. Short-term energy outlook, July 1998

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-07-01

    The Energy Information Administration (EIA) prepares The Short-Term Energy Outlook (energy supply, demand, and price projections) monthly for distribution on the internet at: www.eia.doe.gov/emeu/steo/pub/contents.html. In addition, printed versions of the report are available to subscribers in January, April, July and October. The forecast period for this issue of the Outlook extends from July 1998 through December 1999. Values for second quarter of 1998 data, however, are preliminary EIA estimates (for example, some monthly values for petroleum supply and disposition are derived in part from weekly data reported in EIA`s Weekly Petroleum Status Report) or are calculated from model simulations that use the latest exogenous information available (for example, electricity sales and generation are simulated by using actual weather data). The historical energy data, compiled in the July 1998 version of the Short-Term Integrated Forecasting System (STIFS) database, are mostly EIA data regularly published in the Monthly Energy Review, Petroleum Supply Monthly, and other EIA publications. Minor discrepancies between the data in these publications and the historical data in this Outlook are due to independent rounding. 28 figs., 19 tabs.

  18. Short-term energy outlook, January 1999

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-01-01

    The Energy Information Administration (EIA) prepares the Short-Term Energy Outlook (energy supply, demand, and price projections) monthly. The forecast period for this issue of the Outlook extends from January 1999 through December 2000. Data values for the fourth quarter 1998, however, are preliminary EIA estimates (for example, some monthly values for petroleum supply and disposition are derived in part from weekly data reported in EIA`s Weekly Petroleum Status Report) or are calculated from model simulations that use the latest exogenous information available (for example, electricity sales and generation are simulated by using actual weather data). The historical energy data, compiled in the January 1999 version of the Short-Term Integrated Forecasting System (STIFS) database, are mostly EIA data regularly published in the Monthly Energy Review, Petroleum Supply Monthly, and other EIA publications. Minor discrepancies between the data in these publications and the historical data in this Outlook are due to independent rounding. The STIFS model is driven principally by three sets of assumptions or inputs: estimates of key macroeconomic variables, world oil price assumptions, and assumptions about the severity of weather. Macroeconomic estimates are produced by DRI/McGraw-Hill but are adjusted by EIA to reflect EIA assumptions about the world price of crude oil, energy product prices, and other assumptions which may affect the macroeconomic outlook. By varying the assumptions, alternative cases are produced by using the STIFS model. 28 figs., 19 tabs.

  19. Measuring Short-term Energy Security

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    Ensuring energy security has been at the centre of the IEA mission since its inception, following the oil crises of the early 1970s. While the security of oil supplies remains important, contemporary energy security policies must address all energy sources and cover a comprehensive range of natural, economic and political risks that affect energy sources, infrastructures and services. In response to this challenge, the IEA is currently developing a Model Of Short-term Energy Security (MOSES) to evaluate the energy security risks and resilience capacities of its member countries. The current version of MOSES covers short-term security of supply for primary energy sources and secondary fuels among IEA countries. It also lays the foundation for analysis of vulnerabilities of electricity and end-use energy sectors. MOSES contains a novel approach to analysing energy security, which can be used to identify energy security priorities, as a starting point for national energy security assessments and to track the evolution of a country's energy security profile. By grouping together countries with similar 'energy security profiles', MOSES depicts the energy security landscape of IEA countries. By extending the MOSES methodology to electricity security and energy services in the future, the IEA aims to develop a comprehensive policy-relevant perspective on global energy security. This Brochure provides and overview of the analysis and results. Readers interested in an in-depth discussion of methodology are referred to the MOSES Working Paper.

  20. Developing Short Films of Geoscience Research

    Science.gov (United States)

    Shipman, J. S.; Webley, P. W.; Dehn, J.; Harrild, M.; Kienenberger, D.; Salganek, M.

    2015-12-01

    In today's prevalence of social media and networking, video products are becoming increasingly more useful to communicate research quickly and effectively to a diverse audience, including outreach activities as well as within the research community and to funding agencies. Due to the observational nature of geoscience, researchers often take photos and video footage to document fieldwork or to record laboratory experiments. Here we present how researchers can become more effective storytellers by collaborating with filmmakers to produce short documentary films of their research. We will focus on the use of traditional high-definition (HD) camcorders and HD DSLR cameras to record the scientific story while our research topic focuses on the use of remote sensing techniques, specifically thermal infrared imaging that is often used to analyze time varying natural processes such as volcanic hazards. By capturing the story in the thermal infrared wavelength range, in addition to traditional red-green-blue (RGB) color space, the audience is able to experience the world differently. We will develop a short film specifically designed using thermal infrared cameras that illustrates how visual storytellers can use these new tools to capture unique and important aspects of their research, convey their passion for earth systems science, as well as engage and captive the viewer.

  1. Short wavelength FELs using the SLAC linac

    International Nuclear Information System (INIS)

    Winick, H.; Bane, K.; Boyce, R.

    1993-08-01

    Recent technological developments have opened the possibility to construct a device which we call a Linac Coherent Light Source (LCLS); a fourth generation light source, with brightness, coherence, and peak power far exceeding other sources. Operating on the principle of the free electron laser (FEL), the LCLS would extend the range of FEL operation to much aborter wavelength than the 240 mn that has so far been reached. We report the results of studies of the use of the SLAC linac to drive an LCLS at wavelengths from about 3-100 nm initially and possibly even shorter wavelengths in the future. Lasing would be achieved in a single pass of a low emittance, high peak current, high energy electron beam through a long undulator. Most present FELs use an optical cavity to build up the intensity of the light to achieve lasing action in a low gain oscillator configuration. By eliminating the optical cavity, which is difficult to make at short wavelengths, laser action can be extended to shorter wavelengths by Self-Amplified-Spontaneous-Emission (SASE), or by harmonic generation from a longer wavelength seed laser. Short wavelength, single pass lasers have been extensively studied at several laboratories and at recent workshops

  2. Vanishing honey bees: Is the dying of adult worker bees a consequence of short telomeres and premature aging?

    Science.gov (United States)

    Stindl, Reinhard; Stindl, Wolfgang

    2010-10-01

    Einstein is often quoted to have said that without the bee, mankind would have but 4years to live. It is highly unlikely that he made this comment, which was even mentioned in a Lancet article on honey bees. However, the current vanishing of the bees can have serious consequences for human health, because 35% of the human diet is thought to benefit from pollination. Colony collapse disorder (CCD) in honey bees is characterized by the rapid decline of the adult bee population, leaving the brood and the queen poorly or completely unattended, with no dead bodies in or around the hive. A large study found no evidence that the presence or amount of any individual pesticide or infectious agent occurred more frequently or abundantly in CCD-affected colonies. The growing consensus is that honey bees are suffering from comprised immune systems, which allow various infectious pathogens to invade. The question remains, what causes immunosuppression in many colonies of Apis mellifera in North America and Europe? Telomeres are protective DNA structures located at eukaryotic chromosome tips that shorten in the somatic tissues of animals with age. Lifelong tissue regeneration takes place in Apis mellifera, and worker bees have been shown to senesce. In humans, a vast amount of literature has accumulated on exhausted telomere reserves causing impaired tissue regeneration and age-associated diseases, specifically cancer and immunosuppression. Therefore, we propose a new causative mechanism for the vanishing of the bees: critically short telomeres in long-lived winter bees. We term this the telomere premature aging syndrome. Copyright 2010 Elsevier Ltd. All rights reserved.

  3. Validating a Cantonese short version of the Zarit Burden Interview (CZBI-Short) for dementia caregivers.

    Science.gov (United States)

    Tang, Jennifer Yee-Man; Ho, Andy Hau-Yan; Luo, Hao; Wong, Gloria Hoi-Yan; Lau, Bobo Hi-Po; Lum, Terry Yat-Sang; Cheung, Karen Siu-Lan

    2016-09-01

    The present study aimed to develop and validate a Cantonese short version of the Zarit Burden Interview (CZBI-Short) for Hong Kong Chinese dementia caregivers. The 12-item Zarit Burden Interview (ZBI) was translated into spoken Cantonese and back-translated by two bilingual research assistants and face validated by a panel of experts. Five hundred Chinese dementia caregivers showing signs of stress reported their burden using the translated ZBI and rated their depressive symptoms, overall health, and care recipients' physical functioning and behavioral problems. The factor structure of the translated scale was identified using principal component analysis and confirmatory factor analysis; internal consistency and item-total correlations were assessed; and concurrent validity was tested by correlating the ZBI with depressive symptoms, self-rated health, and care recipients' physical functioning and behavioral problems. The principal component analysis resulted in 11 items loading on a three-factor model comprised role strain, self-criticism, and negative emotion, which accounted for 59% of the variance. The confirmatory factor analysis supported the three-factor model (CZBI-Short) that explained 61% of the total variance. Cronbach's alpha (0.84) and item-total correlations (rho = 0.39-0.71) indicated CZBI-Short had good reliability. CZBI-Short showed correlations with depressive symptoms (r = 0.50), self-rated health (r = -0.26) and care recipients' physical functioning (r = 0.18-0.26) and disruptive behaviors (r = 0.36). The 12-item CZBI-Short is a concise, reliable, and valid instrument to assess burden in Chinese dementia caregivers in clinical and social care settings.

  4. The short short story as a teaching resource for the acquisition of grammar in SFL

    Directory of Open Access Journals (Sweden)

    María Nayra Rodríguez Rodríguez

    2016-07-01

    Full Text Available In the present article we intend to make a reflection on the introduction of target language literature in foreign language classrooms. We will analyze the use of short-short stories as a didactic resource in Spanish as Foreign Language classrooms. To this end, we will research different teaching methodologies that have been implemented and investigate the validity of this genre as a suitable material for teaching grammar. We will make an approximation to Focus on Form as an effective approach, which integrates grammar teaching within a communicative context.

  5. ECONOMIC IMPACT ANALYSIS OF GDOT’S SHORT LINE RAILROADS

    Science.gov (United States)

    2018-04-01

    Short line railroads are critical to Georgias transportation infrastructure and support the efficient movement of goods into and out of the State. Twenty-nine short line railroads operate in Georgia, six of which operate either partially or totall...

  6. Evaluation of Short Term Memory Span Function In Children

    OpenAIRE

    Barış ERGÜL; Arzu ALTIN YAVUZ; Ebru GÜNDOĞAN AŞIK

    2016-01-01

    Although details of the information encoded in the short-term memory where it is stored temporarily be recorded in the working memory in the next stage. Repeating the information mentally makes it remain in memory for a long time. Studies investigating the relationship between short-term memory and reading skills that are carried out to examine the relationship between short-term memory processes and reading comprehension. In this study information coming to short-term memory and the factors ...

  7. Tester Detects Steady-Short Or Intermittent-Open Circuits

    Science.gov (United States)

    Anderson, Bobby L.

    1990-01-01

    Momentary open circuits or steady short circuits trigger buzzer. Simple, portable, lightweight testing circuit sounds long-duration alarm when it detects steady short circuit or momentary open circuit in coaxial cable or other two-conductor transmission line. Tester sensitive to discontinuities lasting 10 microseconds or longer. Used extensively for detecting intermittent open shorts in accelerometer and extensometer cables. Also used as ordinary buzzer-type continuity checker to detect steady short or open circuits.

  8. Synchronous Condenser Allocation for Improving System Short Circuit Ratio

    DEFF Research Database (Denmark)

    Jia, Jundi; Yang, Guangya; Nielsen, Arne Hejde

    2018-01-01

    With converter-based renewable energy sources increasingly integrated into power systems and conventional power plants gradually phased out, future power systems will experience reduced short circuit strength. The deployment of synchronous condensers can serve as a potential solution. This paper...... presents an optimal synchronous condenser allocation method for improving system short circuit ratio at converter point of common coupling using a modified short circuit analysis approach. The total cost of installing new synchronous condensers is minimized while the system short circuit ratios...

  9. Teaching English Using Local Culture Content Short Story

    OpenAIRE

    Sanda, Silfi

    2009-01-01

    This paper is mainly about the use of local culture content short story in developing students' English proficiency and some activities that can be employed for this purpose. The local culture exposed in the short story is the traditional woven clothes of Palembang, Songket in term of process and product. The short story used in this topic is Cek Ipah "The Palembang Songket Weaver". This short story is authors' original work telling about everyday live of palembang songket weaver which covers...

  10. Numerical challenges of short range wake field calculations

    Energy Technology Data Exchange (ETDEWEB)

    Lau, Thomas; Gjonaj, Erion; Weiland, Thomas [Technische Universitaet Darmstadt (Germany). Institut fuer Theorie Elektromagnetischer Felder (TEMF)

    2011-07-01

    For present and future accelerator projects with ultra short bunches the accurate and reliable calculation of short range wake fields is an important issue. However, the numerical calculation of short range wake fields is a numerical challenging task. The presentation gives an overview over the numerical challenges and techniques for short range wake field calculations. Finally, some simulation results obtained by the program PBCI developed at the TU Darmstadt are presented.

  11. Sorting signed permutations by short operations.

    Science.gov (United States)

    Galvão, Gustavo Rodrigues; Lee, Orlando; Dias, Zanoni

    2015-01-01

    During evolution, global mutations may alter the order and the orientation of the genes in a genome. Such mutations are referred to as rearrangement events, or simply operations. In unichromosomal genomes, the most common operations are reversals, which are responsible for reversing the order and orientation of a sequence of genes, and transpositions, which are responsible for switching the location of two contiguous portions of a genome. The problem of computing the minimum sequence of operations that transforms one genome into another - which is equivalent to the problem of sorting a permutation into the identity permutation - is a well-studied problem that finds application in comparative genomics. There are a number of works concerning this problem in the literature, but they generally do not take into account the length of the operations (i.e. the number of genes affected by the operations). Since it has been observed that short operations are prevalent in the evolution of some species, algorithms that efficiently solve this problem in the special case of short operations are of interest. In this paper, we investigate the problem of sorting a signed permutation by short operations. More precisely, we study four flavors of this problem: (i) the problem of sorting a signed permutation by reversals of length at most 2; (ii) the problem of sorting a signed permutation by reversals of length at most 3; (iii) the problem of sorting a signed permutation by reversals and transpositions of length at most 2; and (iv) the problem of sorting a signed permutation by reversals and transpositions of length at most 3. We present polynomial-time solutions for problems (i) and (iii), a 5-approximation for problem (ii), and a 3-approximation for problem (iv). Moreover, we show that the expected approximation ratio of the 5-approximation algorithm is not greater than 3 for random signed permutations with more than 12 elements. Finally, we present experimental results that show

  12. Crystal structure of clustered regularly interspaced short palindromic repeats (CRISPR)-associated Csn2 protein revealed Ca2+-dependent double-stranded DNA binding activity.

    Science.gov (United States)

    Nam, Ki Hyun; Kurinov, Igor; Ke, Ailong

    2011-09-02

    Clustered regularly interspaced short palindromic repeats (CRISPR) and their associated protein genes (cas genes) are widespread in bacteria and archaea. They form a line of RNA-based immunity to eradicate invading bacteriophages and malicious plasmids. A key molecular event during this process is the acquisition of new spacers into the CRISPR loci to guide the selective degradation of the matching foreign genetic elements. Csn2 is a Nmeni subtype-specific cas gene required for new spacer acquisition. Here we characterize the Enterococcus faecalis Csn2 protein as a double-stranded (ds-) DNA-binding protein and report its 2.7 Å tetrameric ring structure. The inner circle of the Csn2 tetrameric ring is ∼26 Å wide and populated with conserved lysine residues poised for nonspecific interactions with ds-DNA. Each Csn2 protomer contains an α/β domain and an α-helical domain; significant hinge motion was observed between these two domains. Ca(2+) was located at strategic positions in the oligomerization interface. We further showed that removal of Ca(2+) ions altered the oligomerization state of Csn2, which in turn severely decreased its affinity for ds-DNA. In summary, our results provided the first insight into the function of the Csn2 protein in CRISPR adaptation by revealing that it is a ds-DNA-binding protein functioning at the quaternary structure level and regulated by Ca(2+) ions.

  13. Crystal Structure of Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-associated Csn2 Protein Revealed Ca[superscript 2+]-dependent Double-stranded DNA Binding Activity

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Ki Hyun; Kurinov, Igor; Ke, Ailong (Cornell); (NWU)

    2012-05-22

    Clustered regularly interspaced short palindromic repeats (CRISPR) and their associated protein genes (cas genes) are widespread in bacteria and archaea. They form a line of RNA-based immunity to eradicate invading bacteriophages and malicious plasmids. A key molecular event during this process is the acquisition of new spacers into the CRISPR loci to guide the selective degradation of the matching foreign genetic elements. Csn2 is a Nmeni subtype-specific cas gene required for new spacer acquisition. Here we characterize the Enterococcus faecalis Csn2 protein as a double-stranded (ds-) DNA-binding protein and report its 2.7 {angstrom} tetrameric ring structure. The inner circle of the Csn2 tetrameric ring is {approx}26 {angstrom} wide and populated with conserved lysine residues poised for nonspecific interactions with ds-DNA. Each Csn2 protomer contains an {alpha}/{beta} domain and an {alpha}-helical domain; significant hinge motion was observed between these two domains. Ca{sup 2+} was located at strategic positions in the oligomerization interface. We further showed that removal of Ca{sup 2+} ions altered the oligomerization state of Csn2, which in turn severely decreased its affinity for ds-DNA. In summary, our results provided the first insight into the function of the Csn2 protein in CRISPR adaptation by revealing that it is a ds-DNA-binding protein functioning at the quaternary structure level and regulated by Ca{sup 2+} ions.

  14. In Search of Decay in Verbal Short-Term Memory

    Science.gov (United States)

    Berman, Marc G.; Jonides, John; Lewis, Richard L.

    2009-01-01

    Is forgetting in the short term due to decay with the mere passage of time, interference from other memoranda, or both? Past research on short-term memory has revealed some evidence for decay and a plethora of evidence showing that short-term memory is worsened by interference. However, none of these studies has directly contrasted decay and…

  15. Validity of Two WPPSI Short Forms in Outpatient Clinic Settings.

    Science.gov (United States)

    Haynes, Jack P.; Atkinson, David

    1983-01-01

    Investigated the validity of subtest short forms for the Wechsler Preschool and Primary Scale of Intelligence in an outpatient population of 116 children. Data showed that the short forms underestimated actual level of intelligence and supported use of a short form only as a brief screening device. (LLL)

  16. 30 CFR 56.12065 - Short circuit and lightning protection.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Short circuit and lightning protection. 56... Electricity § 56.12065 Short circuit and lightning protection. Powerlines, including trolley wires, and telephone circuits shall be protected against short circuits and lightning. ...

  17. 30 CFR 57.12065 - Short circuit and lightning protection.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Short circuit and lightning protection. 57... MINES Electricity Surface Only § 57.12065 Short circuit and lightning protection. Powerlines, including trolley wires, and telephone circuits shall be protected against short circuits and lightning. ...

  18. 26 CFR 1.6655-5 - Short taxable year.

    Science.gov (United States)

    2010-04-01

    ... Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Additions to the Tax, Additional Amounts, and Assessable Penalties § 1.6655-5 Short taxable... beginning with its initial short taxable year to the time it files its tax return for its initial short...

  19. Low frequency interference between short synchrotron radiation sources

    Directory of Open Access Journals (Sweden)

    F. Méot

    2001-06-01

    Full Text Available A recently developed analytical formalism describing low frequency far-field synchrotron radiation (SR is applied to the calculation of spectral angular radiation densities from interfering short sources (edge, short magnet. This is illustrated by analytical calculation of synchrotron radiation from various assemblies of short dipoles, including an “isolated” highest density infrared SR source.

  20. Short Term Airing by Natural Ventilation

    DEFF Research Database (Denmark)

    Heiselberg, Per; Perino, M.

    2010-01-01

    The need to improve the energy efficiency of buildings requires new and more efficient ventilation systems. It has been demonstrated that innovative operating concepts that make use of natural ventilation seem to be more appreciated by occupants. Among the available ventilation strategies...... that are currently available, buoyancy driven, single-sided natural ventilation has proved to be very effective and can provide high air change rates for temperature and Indoor Air Quality (IAQ) control. However, to promote a wider distribution of these systems an improvement in the knowledge of their working...... airflow rate, ventilation efficiency, thermal comfort and dynamic temperature conditions. A suitable laboratory test rig was developed to perform extensive experimental analyses of the phenomenon under controlled and repeatable conditions. The results showed that short-term window airing is very effective...

  1. [Flexor tendon repair: a short story].

    Science.gov (United States)

    Moutet, F; Corcella, D; Forli, A; Mesquida, V

    2014-12-01

    This short story of flexor tendon repair aims to illustrate hesitations and wanderings of this surgery. Obviously tendon repair was very early considered, but it developed and diffused rather lately. It became a routine practice only in 20th century. This was due on the one hand, in Occident, to the Galen's dogmatic interdiction, on the other hand, to the repair difficulties of this paradoxical structure. Actually tendon is made of fibroblasts and collagen (sticky substances), and then its only goal is to move. According to this necessity, whatever the used techniques are, gliding is the final purpose. Technical evolutions are illustrated by historical contributions to flexor tendon surgery of several "giants" of hand surgery. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  2. Treatment of short-lived radioactive wastes

    International Nuclear Information System (INIS)

    Yamaguchi, Chiri

    1976-01-01

    Recently short life nuclides have come to be utilized increasingly as diagnostic radioisotopes, and Tc-99m (half-life; 6.05 hours) and Ga-67 (half-life 7.79 hours) are replacing the most nuclides fomerly used in vivo test. Such development of radioactive products inevitably causes the rapid increase of their wastes. At present, the radioactive wastes produced by hospitals and university laboratories in Japan are collected by the Japan Radioisotope Association, and treated by the Japan Atomic Energy Research Institute. These wastes are divided into combustibles and incombustibles to store in the store house in the Japan Atomic Energy Research Institute. The present law in Japan contains the contradiction which treats the matter with one several millionth of radioactivity after decay same as the original radioactive matter. Thus solid must be stored permanently, while gas and liquid can be discharged after dilution. (Kobatake, H.)

  3. Short Rayleigh Length Free Electron Lasers

    CERN Document Server

    Crooker, P P; Armstead, R L; Blau, J

    2004-01-01

    Conventional free electron laser (FEL) oscillators minimize the optical mode volume around the electron beam in the undulator by making the resonator Rayleigh length about one third of the undulator length. This maximizes gain and beam-mode coupling. In compact configurations of high-power infrared FELs or moderate power UV FELs, the resulting optical intensity can damage the resonator mirrors. To increase the spot size and thereby reduce the optical intensity at the mirrors below the damage threshold, a shorter Rayleigh length can be used, but the FEL interaction is significantly altered. A new FEL interaction is described and analyzed with a Rayleigh length that is only one tenth the undulator length, or less. The effect of mirror vibration and positioning are more critical in the short Rayleigh length design, but we find that they are still within normal design tolerances.

  4. Separation of short-lived fission products

    International Nuclear Information System (INIS)

    Tamai, Tadaharu; Ohyoshi, Emiko; Ohyoshi, Akira; Kiso, Yoshiyuki; Shinagawa, Mutsuaki.

    1976-01-01

    A rbief review is presented on the various methods of separation available for both gaseous and liquid states, for the separation of short-lived fission products formed by binary fission of neutron irradiated uranium. The means available for gaseous state are the hot atom reaction, the hydride method and on-line mass separation. For liquid state, use can be made of precipitation, ionic or atomic exchange, solvent extraction and paper electrophoresis. Particular reference is made to electrophoretic separation of ions produced by fission in aqueous solution of uranium. The principle of electrophoretic separation and the procedures for separating the element of interest from the other fission products are outlined, with reference made to the results obtained with the method by the present authors. The elements in question are alkalines, alkaline earths, rare earths, halogens, selenium and

  5. Using Short Videos to Teach Research Ethics

    Science.gov (United States)

    Loui, M. C.

    2014-12-01

    Created with support from the National Science Foundation, EthicsCORE (www.natonalethicscenter.org) is an online resource center for ethics in science and engineering. Among the resources, EthicsCORE hosts short video vignettes produced at the University of Nebraska - Lincoln that dramatize problems in the responsible conduct of research, such as peer review of journal submissions, and mentoring relationships between faculty and graduate students. I will use one of the video vignettes in an interactive pedagogical demonstration. After showing the video, I will ask participants to engage in a think-pair-share activity on the professional obligations of researchers. During the sharing phase, participants will supply the reasons for these obligations.

  6. Deterministic nonlinear systems a short course

    CERN Document Server

    Anishchenko, Vadim S; Strelkova, Galina I

    2014-01-01

    This text is a short yet complete course on nonlinear dynamics of deterministic systems. Conceived as a modular set of 15 concise lectures it reflects the many years of teaching experience by the authors. The lectures treat in turn the fundamental aspects of the theory of dynamical systems, aspects of stability and bifurcations, the theory of deterministic chaos and attractor dimensions, as well as the elements of the theory of Poincare recurrences.Particular attention is paid to the analysis of the generation of periodic, quasiperiodic and chaotic self-sustained oscillations and to the issue of synchronization in such systems.  This book is aimed at graduate students and non-specialist researchers with a background in physics, applied mathematics and engineering wishing to enter this exciting field of research.

  7. Short-term forecasting of internal migration.

    Science.gov (United States)

    Frees, E W

    1993-11-01

    A new methodological approach to the forecasting of short-term trends in internal migration in the United States is introduced. "Panel-data (or longitudinal-data) models are used to represent the relationship between destination-specific out-migration and several explanatory variables. The introduction of this methodology into the migration literature is possible because of some new and improved databases developed by the U.S. Bureau of the Census.... Data from the Bureau of Economic Analysis are used to investigate the incorporation of exogenous factors as variables in the model." The exogenous factors considered include employment and unemployment, income, population size of state, and distance between states. The author concludes that "when one...includes additional parameters that are estimable in longitudinal-data models, it turns out that there is little additional information in the exogenous factors that is useful for forecasting." excerpt

  8. Economics of solar energy: Short term costing

    Science.gov (United States)

    Klee, H.

    The solar economics based on life cycle costs are refuted as both imaginary and irrelevant. It is argued that predicting rates of inflation and fuel escalation, expected life, maintenance costs, and legislation over the next ten to twenty years is pure guesswork. Furthermore, given the high mobility level of the U.S. population, the average consumer is skeptical of long run arguments which will pay returns only to the next owners. In the short term cost analysis, the house is sold prior to the end of the expected life of the system. The cash flow of the seller and buyer are considered. All the relevant factors, including the federal tax credit and the added value of the house because of the solar system are included.

  9. Origin of Short-Perihelion Comets

    Science.gov (United States)

    Guliyev, A. S.

    2011-01-01

    New regularities for short-perihelion comets are found. Distant nodes of cometary orbits of Kreutz family are concentrated in a plane with ascending node 76 and inclination 267 at the distance from 2 up to 3 a.u. and in a very narrow interval of longitudes. There is a correlation dependence between q and cos I concerning the found plane (coefficient of correlation 0.41). Similar results are received regarding to cometary families of Meyer, Kracht and Marsden. Distant nodes of these comets are concentrated close three planes (their parameters are discussed in the article) and at distances 1.4; 0.5; 6 a.u. accordingly. It is concluded that these comet groups were formed as a result of collision of parent bodies with meteoric streams. One more group, consisting of 7 comets is identified. 5 comet pairs are selected among sungrazers.

  10. Nonlocality and short-range wetting phenomena.

    Science.gov (United States)

    Parry, A O; Romero-Enrique, J M; Lazarides, A

    2004-08-20

    We propose a nonlocal interfacial model for 3D short-range wetting at planar and nonplanar walls. The model is characterized by a binding-potential functional depending only on the bulk Ornstein-Zernike correlation function, which arises from different classes of tubelike fluctuations that connect the interface and the substrate. The theory provides a physical explanation for the origin of the effective position-dependent stiffness and binding potential in approximate local theories and also obeys the necessary classical wedge covariance relationship between wetting and wedge filling. Renormalization group and computer simulation studies reveal the strong nonperturbative influence of nonlocality at critical wetting, throwing light on long-standing theoretical problems regarding the order of the phase transition.

  11. Nonlocality and Short-Range Wetting Phenomena

    Science.gov (United States)

    Parry, A. O.; Romero-Enrique, J. M.; Lazarides, A.

    2004-08-01

    We propose a nonlocal interfacial model for 3D short-range wetting at planar and nonplanar walls. The model is characterized by a binding-potential functional depending only on the bulk Ornstein-Zernike correlation function, which arises from different classes of tubelike fluctuations that connect the interface and the substrate. The theory provides a physical explanation for the origin of the effective position-dependent stiffness and binding potential in approximate local theories and also obeys the necessary classical wedge covariance relationship between wetting and wedge filling. Renormalization group and computer simulation studies reveal the strong nonperturbative influence of nonlocality at critical wetting, throwing light on long-standing theoretical problems regarding the order of the phase transition.

  12. Short course review and the future

    Energy Technology Data Exchange (ETDEWEB)

    Corden, Pierce S. [Center for Science, Technology and Security Policy, American Association for the Advancement of Science, Washington, DC 20005 (United States)

    2014-05-09

    The presentations at the short course that were the basis of the present Proceedings covered many critical issues related to the objective of eliminating nuclear weapons as a means of ensuring global security and stability. This paper is based on the concluding talk, which briefly reviewed the course, offered a net assessment of where the project of elimination - a policy objective for nearly all the world's states - stands, and discussed some of the factors that need to be dealt with in achieving a nuclear weapon free world. These include understanding what 'proliferation' means and how it has changed over time, how the spread of nuclear weapons has proceeded over time, both 'vertical' in numbers and 'horizontal' to additional countries, what way the 'vector' of reversing proliferation is pointing, and the roles of nuclear energy and international governance.

  13. Nanowire failure: long = brittle and short = ductile.

    Science.gov (United States)

    Wu, Zhaoxuan; Zhang, Yong-Wei; Jhon, Mark H; Gao, Huajian; Srolovitz, David J

    2012-02-08

    Experimental studies of the tensile behavior of metallic nanowires show a wide range of failure modes, ranging from ductile necking to brittle/localized shear failure-often in the same diameter wires. We performed large-scale molecular dynamics simulations of copper nanowires with a range of nanowire lengths and provide unequivocal evidence for a transition in nanowire failure mode with change in nanowire length. Short nanowires fail via a ductile mode with serrated stress-strain curves, while long wires exhibit extreme shear localization and abrupt failure. We developed a simple model for predicting the critical nanowire length for this failure mode transition and showed that it is in excellent agreement with both the simulation results and the extant experimental data. The present results provide a new paradigm for the design of nanoscale mechanical systems that demarcates graceful and catastrophic failure. © 2012 American Chemical Society

  14. Measurements of Short-Lived Fission Isomers

    Science.gov (United States)

    Finch, Sean; Bhike, Megha; Howell, Calvin; Krishichayan, Fnu; Tornow, Werner

    2016-09-01

    Fission yields of the short lived isomers 134mTe (T1 / 2 = 162 ns) and 136mXe (T1 / 2 = 2 . 95 μs) were measured for 235U and 238U. The isomers were detected by the γ rays associated with the decay of the isomeric states using high-purity germanium detectors. Fission was induced using both monoenergetic γ rays and neutrons. At TUNL's High-Intensity Gamma-ray Source (HI γS), γ rays of 9 and 11 MeV were produced . Monoenergetic 8 MeV neutrons were produced at TUNL's tandem accelerator laboratory. Both beams were pulsed to allow for precise time-gated spectroscopy of both prompt and delayed γ rays following fission. This technique offers a non-destructive probe of special nuclear materials that is sensitive to the isotopic identity of the fissile material.

  15. Short-term plasticity in auditory cognition.

    Science.gov (United States)

    Jääskeläinen, Iiro P; Ahveninen, Jyrki; Belliveau, John W; Raij, Tommi; Sams, Mikko

    2007-12-01

    Converging lines of evidence suggest that auditory system short-term plasticity can enable several perceptual and cognitive functions that have been previously considered as relatively distinct phenomena. Here we review recent findings suggesting that auditory stimulation, auditory selective attention and cross-modal effects of visual stimulation each cause transient excitatory and (surround) inhibitory modulations in the auditory cortex. These modulations might adaptively tune hierarchically organized sound feature maps of the auditory cortex (e.g. tonotopy), thus filtering relevant sounds during rapidly changing environmental and task demands. This could support auditory sensory memory, pre-attentive detection of sound novelty, enhanced perception during selective attention, influence of visual processing on auditory perception and longer-term plastic changes associated with perceptual learning.

  16. Short range order in liquid pnictides

    International Nuclear Information System (INIS)

    Mayo, M; Makov, G; Yahel, E; Greenberg, Y

    2013-01-01

    Liquid pnictides have anomalous physical properties and complex radial distribution functions. The quasi-crystalline model of liquid structure is applied to interpret the three-dimensional structure of liquid pnictides. It is shown that all the column V elements can be characterized by a short range order lattice symmetry similar to that of the underlying solid, the A7 structure, which originates from a Peierls distorted simple cubic lattice. The evolution of the liquid structure down the column as well as its temperature and pressure dependence is interpreted by means of the effect of thermodynamic parameters on the Peierls distortion. Surprisingly, it is found that the Peierls effect increases with temperature and the nearest neighbour distances exhibit negative thermal expansion. (paper)

  17. Magnetic Resonance Fingerprinting with short relaxation intervals.

    Science.gov (United States)

    Amthor, Thomas; Doneva, Mariya; Koken, Peter; Sommer, Karsten; Meineke, Jakob; Börnert, Peter

    2017-09-01

    The aim of this study was to investigate a technique for improving the performance of Magnetic Resonance Fingerprinting (MRF) in repetitive sampling schemes, in particular for 3D MRF acquisition, by shortening relaxation intervals between MRF pulse train repetitions. A calculation method for MRF dictionaries adapted to short relaxation intervals and non-relaxed initial spin states is presented, based on the concept of stationary fingerprints. The method is applicable to many different k-space sampling schemes in 2D and 3D. For accuracy analysis, T 1 and T 2 values of a phantom are determined by single-slice Cartesian MRF for different relaxation intervals and are compared with quantitative reference measurements. The relevance of slice profile effects is also investigated in this case. To further illustrate the capabilities of the method, an application to in-vivo spiral 3D MRF measurements is demonstrated. The proposed computation method enables accurate parameter estimation even for the shortest relaxation intervals, as investigated for different sampling patterns in 2D and 3D. In 2D Cartesian measurements, we achieved a scan acceleration of more than a factor of two, while maintaining acceptable accuracy: The largest T 1 values of a sample set deviated from their reference values by 0.3% (longest relaxation interval) and 2.4% (shortest relaxation interval). The largest T 2 values showed systematic deviations of up to 10% for all relaxation intervals, which is discussed. The influence of slice profile effects for multislice acquisition is shown to become increasingly relevant for short relaxation intervals. In 3D spiral measurements, a scan time reduction of 36% was achieved, maintaining the quality of in-vivo T1 and T2 maps. Reducing the relaxation interval between MRF sequence repetitions using stationary fingerprint dictionaries is a feasible method to improve the scan efficiency of MRF sequences. The method enables fast implementations of 3D spatially

  18. Robust Short-Lag Spatial Coherence Imaging.

    Science.gov (United States)

    Nair, Arun Asokan; Tran, Trac Duy; Bell, Muyinatu A Lediju

    2018-03-01

    Short-lag spatial coherence (SLSC) imaging displays the spatial coherence between backscattered ultrasound echoes instead of their signal amplitudes and is more robust to noise and clutter artifacts when compared with traditional delay-and-sum (DAS) B-mode imaging. However, SLSC imaging does not consider the content of images formed with different lags, and thus does not exploit the differences in tissue texture at each short-lag value. Our proposed method improves SLSC imaging by weighting the addition of lag values (i.e., M-weighting) and by applying robust principal component analysis (RPCA) to search for a low-dimensional subspace for projecting coherence images created with different lag values. The RPCA-based projections are considered to be denoised versions of the originals that are then weighted and added across lags to yield a final robust SLSC (R-SLSC) image. Our approach was tested on simulation, phantom, and in vivo liver data. Relative to DAS B-mode images, the mean contrast, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) improvements with R-SLSC images are 21.22 dB, 2.54, and 2.36, respectively, when averaged over simulated, phantom, and in vivo data and over all lags considered, which corresponds to mean improvements of 96.4%, 121.2%, and 120.5%, respectively. When compared with SLSC images, the corresponding mean improvements with R-SLSC images were 7.38 dB, 1.52, and 1.30, respectively (i.e., mean improvements of 14.5%, 50.5%, and 43.2%, respectively). Results show great promise for smoothing out the tissue texture of SLSC images and enhancing anechoic or hypoechoic target visibility at higher lag values, which could be useful in clinical tasks such as breast cyst visualization, liver vessel tracking, and obese patient imaging.

  19. Why do short term workers have high mortality?

    DEFF Research Database (Denmark)

    Kolstad, Henrik; Olsen, Jørn

    1999-01-01

    or violence, the rate ratios for short term employment were 2.30 (95% Cl 1.74-3.06) and 1.86 (95% Cl 1.35-2.56), respectively. An unhealthy lifestyle may also be a determinant of short term employment. While it is possible in principle to adjust for lifestyle factors if proper data are collected, the health......Increased mortality is often reported among workers in short term employment. This may indicate either a health-related selection process or the presence of different lifestyle or social conditions among short term workers. The authors studied these two aspects of short term employment among 16...

  20. Preferred Hosts for Short-Period Exoplanets

    Science.gov (United States)

    Kohler, Susanna

    2015-12-01

    In an effort to learn more about how planets form around their host stars, a team of scientists has analyzed the population of Kepler-discovered exoplanet candidates, looking for trends in where theyre found.Planetary OccurrenceSince its launch in 2009, Kepler has found thousands of candidate exoplanets around a variety of star types. Especially intriguing is the large population of super-Earths and mini-Neptunes planets with masses between that of Earth and Neptune that have short orbital periods. How did they come to exist so close to their host star? Did they form in situ, or migrate inwards, or some combination of both processes?To constrain these formation mechanisms, a team of scientists led by Gijs Mulders (University of Arizona and NASAs NExSS coalition) analyzed the population of Kepler planet candidates that have orbital periods between 2 and 50 days.Mulders and collaborators used statistical reconstructions to find the average number of planets, within this orbital range, around each star in the Kepler field. They then determined how this planet occurrence rate changed for different spectral types and therefore the masses of the host stars: do low-mass M-dwarf stars host more or fewer planets than higher-mass, main-sequence F, G, or K stars?Challenging ModelsAuthors estimates for the occurrence rate for short-period planets of different radii around M-dwarfs (purple) and around F, G, and K-type stars (blue). [Mulders et al. 2015]The team found that M dwarfs, compared to F, G, or K stars, host about half as many large planets with orbital periods of P 50 days. But, surprisingly, they host significantly more small planets, racking up an average of 3.5 times the number of planets in the size range of 12.8 Earth-radii.Could it be that M dwarfs have a lower total mass of planets, but that mass is distributed into more, smaller planets? Apparently not: the authors show that the mass of heavy elements trapped in short-orbital-period planets is higher for M