355 research outputs found

    Dynamics of semifluxons in Nb long Josephson 0-pi junctions

    Full text link
    We propose, implement and test experimentally long Josephson 0-pi junctions fabricated using conventional Nb-AlOx-Nb technology. We show that using a pair of current injectors, one can create an arbitrary discontinuity of the Josephson phase and in particular a pi-discontinuity, just like in d-wave/s-wave or in d-wave/d-wave junctions, and study fractional Josephson vortices which spontaneously appear. Moreover, using such junctions, we can investigate the \emph{dynamics} of the fractional vortices -- a domain which is not yet available for natural 0-pi-junctions due to their inherently high damping. We observe half-integer zero-field steps which appear on the current-voltage characteristics due to hopping of semifluxons.Comment: Fractional vortices in conventional superconductors ;-

    BETWEEN BROADCASTING POLITICAL MESSAGES AND INTERACTING WITH VOTERS

    Get PDF
    Politicians across Western democracies are increasingly adopting and experimenting with Twitter, particularly during election time. The purpose of this article is to investigate how candidates are using it during an election campaign. The aim is to create a typology of the various ways in which candidates behaved on Twitter. Our research, which included a content analysis of tweets (nā€‰=ā€‰26,282) from all twittering Conservative, Labour and Liberal Democrat candidates (nā€‰=ā€‰416) during the 2010 UK General Election campaign, focused on four aspects of tweets: type, interaction, function and topic. By examining candidates' twittering behaviour, the authors show that British politicians mainly used Twitter as a unidirectional form of communication. However, there were a group of candidates who used it to interact with voters by, for example, mobilizing, helping and consulting them, thus tapping into the potential Twitter offers for facilitating a closer relationship with citizens

    Influence of Methomyl (Copter 90%) on certain biochemical activities and histological structures of land snails Monacha cartusiana

    Full text link
    This manuscript was conducted to spotlight the toxic effect of two sub-lethal concentrations of Methomyl (Copter) LC20 (0.075 g/L) and LC40 (0.180 g/L) on some biochemical parameters and histological alterations for land snail Monacha Cartusiana (Muller, 1774). Land snails belong to the class Gastropoda and Phylum Mollusca. This study cleared that both the used concentrations (of Copter) caused a significant increase for activities of three enzymes: alkaline phosphatase (ALP), alanine amino transaminase (ALT), and Aspartate amino transaminase (AST) after 24, 48, and 72 h from exposure starting. In contrast, a total protein (TP) activity decreased at exposure for two concentrations at all lethality periods. Both concentrations of Copter (0.0.75 g/L and 0.180 g/L) have shown histological changes for land snail tissues after 96 h of exposure; digestive gland, hermaphrodite gland, foot, and mantle. Degeneration, rupture, and vacuolization for digestive cells have been shown; furthermore, hemolytic infiltration in connective tissue will be recognized for the digestive gland. The Oocyte and sperm show degenerated with deformation in the connective tissue of the hermaphrodite gland. Likewise, deformation in the muscle fiber layer of the foot in the land snail distorts the epidermis and mucus gland suffering from necrosis. Moreover, mantle shows rapture in epidermis layer, deformed in muscle fiber layer, and vacuolization and necrosis take place in mucus gland. Ā© 2021 The Author(s

    Outlier detection and classification in sensor data streams for proactive decision support systems

    Get PDF
    A paper has a deal with the problem of quality assessment in sensor data streams accumulated by proactive decision support systems. The new problem is stated where outliers need to be detected and to be classified according to their nature of origin. There are two types of outliers defined; the first type is about misoperations of a system and the second type is caused by changes in the observed system behavior due to inner and external influences. The proposed method is based on the data-driven forecast approach to predict the values in the incoming data stream at the expected time. This method includes the forecasting model and the clustering model. The forecasting model predicts a value in the incoming data stream at the expected time to find the deviation between a real observed value and a predicted one. The clustering method is used for taxonomic classification of outliers. Constructive neural networks models (CoNNS) and evolving connectionists systems (ECS) are used for prediction of sensors data. There are two real world tasks are used as case studies. The maximal values of accuracy are 0.992 and 0.974, and F1 scores are 0.967 and 0.938, respectively, for the first and the second tasks. The conclusion contains findings how to apply the proposed method in proactive decision support systems

    Emerging Anthelmintic Resistance in Poultry: Can ethnopharmacological approaches offer a solution?

    Get PDF
    Limited pharmacological studies have been conducted on plant species used against poultry helminths. The objective of this study was to provide a basis for plant based anthelmintics as possible alternatives against poultry anthelmintic resistance. The study justified the need for alternative anthelmintics. The study places emphasis on the increasing anthelmintic resistance, mechanism of resistance, and preparational protocols for plant anthelmintics and their associated mechanism of action. Pharmaceutical studies on plants as alternative therapies for the control of helminth parasites have not been fully explored especially in several developing countries. Plants from a broad range of species produce a wide variety of compounds that are potential anthelmintics candidates. Important phenolic acids have been found in Brassica rapa L. and Terminalia avicenniodes Guill. and Perri that affect the cell signaling pathways and gene expression. Benzo (c) phenanthridine and isoquinoline alkaloids are neurotoxic to helminths. Steroidal saponins (polyphyllin D and dioscin) interact with helminthic mitochondrial activity, alter cell membrane permeability, vacuolation and membrane damage. Benzyl isothiocyanate glucosinolates interfere with DNA replication and protein expression, while isoflavones from Acacia oxyphylla cause helminth flaccid paralysis, inhibit energy generation, and affect calcium utilization. Condensed tannins have been shown to cause the death of nematodes and paralysis leading to expulsion from the gastro-intestinal tract. Flavonoids from Chenopodium album L and Mangifera indica L act through the action of phosphodiesterase and Ca(2+)-ATPase, and flavonoids and tannins have been shown to act synergistically and are complementary to praziquantel. Artemisinins from Artemisia cina O. Berg are known to disrupt mitochondrial ATP production. Terpenoids from Cucurbita moschata L disrupt neurotransmission leading to paralysis as well as disruption of egg hatching. Yeast particle encapsulated terpenes are effective for the control of albendazole-resistant helminths

    High RBM3 expression in prostate cancer independently predicts a reduced risk of biochemical recurrence and disease progression

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>High expression of the RNA-binding protein RBM3 has previously been found to be associated with good prognosis in breast cancer, ovarian cancer, malignant melanoma and colorectal cancer. The aim of this study was to examine the prognostic impact of immunohistochemical RBM3 expression in prostate cancer.</p> <p>Findings</p> <p>Immunohistochemical RBM3 expression was examined in a tissue microarray with malignant and benign prostatic specimens from 88 patients treated with radical prostatectomy for localized disease. While rarely expressed in benign prostate gland epithelium, RBM3 was found to be up-regulated in prostate intraepithelial neoplasia and present in various fractions and intensities in invasive prostate cancer. High nuclear RBM3 expression was significantly associated with a prolonged time to biochemical recurrence (BCR) (HR 0.56, 95% CI: 0.34-0.93, <it>p </it>= 0.024) and clinical progression (HR 0.09, 95% CI: 0.01-0.71, <it>p = </it>0.021). These associations remained significant in multivariate analysis, adjusted for preoperative PSA level in blood, pathological Gleason score and presence or absence of extracapsular extension, seminal vesicle invasion and positive surgical margin (HR 0.41, 95% CI: 0.19-0.89, <it>p </it>= 0.024 for BCR and HR 0.06, 95% CI: 0.01-0.50, <it>p = </it>0.009 for clinical progression).</p> <p>Conclusion</p> <p>Our results demonstrate that high nuclear expression of RBM3 in prostate cancer is associated with a prolonged time to disease progression and, thus, a potential biomarker of favourable prognosis. The value of RBM3 for prognostication, treatment stratification and follow-up of prostate cancer patients should be further validated in larger studies.</p

    The ligational behavior of an isatinic quinolyl hydrazone towards copper(II)- ions

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The importance of the isatinic quinolyl hydrazones arises from incorporating the quinoline ring with the indole ring. Quinoline ring has therapeutic and biological activities whereas, the indole ring occurs in Jasmine flowers and Orange blossoms. As a ligand, the isatin moiety is potentially ambidentate and can coordinate the metal ions either through its lactam or lactim forms. In a previous study, the ligational behavior of a phenolic quinolyl hydrazone towards copper(II)- ions has been studied. As continuation of our interest, the present study is planned to check the ligational behavior of an isatinic quinolyl hydrazone.</p> <p>Results</p> <p>New homo- and heteroleptic copper(II)- complexes were obtained from the reaction of an isatinic quinolyl hydrazone (HL) with several copper(II)- salts <it>viz. </it>ClĖ‰, BrĖ‰, NO<sub>3</sub>Ė‰, ClO<sub>4</sub><sup>-</sup>, SO<sub>4</sub><sup>2- </sup>and AcO<sup>-</sup>. The obtained complexes have O<sub>h</sub>, T<sub>d </sub>and D<sub>4h</sub>- symmetry and fulfill the strong coordinating ability of ClĖ‰, BrĖ‰, NO<sub>3</sub>Ė‰ and SO<sub>4</sub><sup>2- </sup>anions. Depending on the type of the anion, the ligand coordinates the copper(II)- ions either through its lactam (NO<sub>3</sub>Ė‰ and ClO<sub>4</sub><sup>-</sup>) or lactim (the others) forms.</p> <p>Conclusion</p> <p>The effect of anion for the same metal ion is obvious from either the geometry of the isolated complexes (O<sub>h</sub>, T<sub>d </sub>and D<sub>4h</sub>) or the various modes of bonding. Also, the obtained complexes fulfill the strong coordinating ability of ClĖ‰, BrĖ‰, NO<sub>3</sub>Ė‰ and SO<sub>4</sub><sup>2- </sup>anions in consistency with the donor ability of the anions. In case of copper(II)- acetate, a unique homoleptic complex (<b>5</b>) was obtained in which the AcO<sup>- </sup>anion acts as a base enough to quantitatively deprotonate the hydrazone. The isatinic hydrazone uses its lactim form in most complexes.</p

    Racism, anti-racist practice and social work: articulating the teaching and learning experiences of Black social workers

    Get PDF
    In the mid 1990s a Black practice teacher programme was established in Manchester and Merseyside with the primary aim to increase the number of Black practice teachers in social work organisations, and in turn provide a supportive and encouraging learning environment for Black student social workers whilst on placement. In the northā€west of England research has been undertaken, to establish the quality of the practice teaching and student learning taking place with Black practice teachers and students. This paper is an exploration of the ideas generated within the placement process that particularly focused on the discourse of racism and antā€racist practice. Black students and practice teachers explain their understanding of racism and antiā€racist practice within social work. From the research, the paper will critique some of the ideas concerning antiā€racism. In particular, it will question whether antiā€racist social work practice needs to be reā€evaluated in the light of a context with new migrants, asylum seekers and refugees. It will concluded, by arguing that whilst the terms antiā€racism, Black and Minority Ethnic have resonance as a form of political strategic essentialism, it is important to develop more positive representations in the future

    Folding-competent and folding-defective forms of Ricin A chain have different fates following retrotranslocation from the endoplasmic reticulum

    Get PDF
    We report that a toxic polypeptide retaining the potential to refold upon dislocation from the endoplasmic reticulum (ER) to the cytosol (ricin A chain; RTA) and a misfolded version that cannot (termed RTAĪ”), follow ER-associated degradation (ERAD) pathways in Saccharomyces cerevisiae that substantially diverge in the cytosol. Both polypeptides are dislocated in a step mediated by the transmembrane Hrd1p ubiquitin ligase complex and subsequently degraded. Canonical polyubiquitylation is not a prerequisite for this interaction because a catalytically inactive Hrd1p E3 ubiquitin ligase retains the ability to retrotranslocate RTA, and variants lacking one or both endogenous lysyl residues also require the Hrd1p complex. In the case of native RTA, we established that dislocation also depends on other components of the classical ERAD-L pathway as well as an ongoing ERā€“Golgi transport. However, the dislocation pathways deviate strikingly upon entry into the cytosol. Here, the CDC48 complex is required only for RTAĪ”, although the involvement of individual ATPases (Rpt proteins) in the 19S regulatory particle (RP) of the proteasome, and the 20S catalytic chamber itself, is very different for the two RTA variants. We conclude that cytosolic ERAD components, particularly the proteasome RP, can discriminate between structural features of the same substrate

    The ligational behavior of a phenolic quinolyl hydrazone towards copper(II)- ions

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The heterocyclic hydrazones constitute an important class of biologically active drug molecules. The hydrazones have also been used as herbicides, insecticides, nematocides, redenticides, and plant growth regulators as well as plasticizers and stabilizers for polymers. The importance of the phenolic quinolyl hydrazones arises from incorporating the quinoline ring with the phenolic compound; 2,4-dihydroxy benzaldehyde. Quinoline ring has therapeutic and biological activities whereas, phenols have antiseptic and disinfectants activities and are used in the preparation of dyes, bakelite and drugs. The present study is planned to check the effect of the counter anions on the type and geometry of the isolated copper(II)- complexes as well as the ligational behavior of the phenolic hydrazone; 4-[(2-(4,8-dimethylquinolin-2-yl)hydrazono)methyl] benzene-1,3-diol; (H<sub>2</sub>L).</p> <p>Results</p> <p>A phenolic quinolyl hydrazone (H<sub>2</sub>L) was allowed to react with various copper(II)- salts (Clā€¾, Brā€¾, NO<sub>3</sub>ā€¾, ClO<sub>4</sub>ā€¾, AcOā€¾, SO<sub>4</sub><sup>2-</sup>). The reactions afforded dimeric complexes (ClO<sub>4</sub>ā€¾, AcOā€¾ ), a binuclear complex (NO<sub>3</sub>ā€¾ ) and mononuclear complexes (the others; Clā€¾, Brā€¾, SO<sub>4</sub><sup>2-</sup>). The isolated copper(II)- complexes have octahedral, square pyramid and square planar geometries. Also, they reflect the strong coordinating ability of NO<sub>3</sub>ā€¾, Clā€¾, Brā€¾, AcOā€¾ and SO<sub>4</sub><sup>2- </sup>anions. Depending on the type of the anion, the ligand showed three different modes of bonding <it>viz</it>. (NN)<sup>0 </sup>for the mononuclear complexes (<b>3, 4, 6</b>), (NO)<sup>- </sup>with O- bridging for the dimeric complexes (<b>1, 5</b>) and a mixed mode [(NN)<sup>0 </sup>+ (NO)<sup>- </sup>with O- bridging] for the binuclear nitrato- complex (<b>2</b>).</p> <p>Conclusion</p> <p>The ligational behavior of the phenolic hydrazone (H<sub>2</sub>L) is highly affected by the type of the anion. The isolated copper(II)- complexes reflect the strong coordinating power of the SO<sub>4</sub><sup>2-</sup>, AcOā€¾, Brā€¾, Clā€¾ and NO<sub>3</sub>ā€¾ anions. Also, they reflect the structural diversity (octahedral, square pyramid and square planar) depending on the type of the counter anion.</p
    • ā€¦
    corecore