Anti-negation method for handling negation words in question answering system

The question answer (QA) system for a reading comprehension task tries to answer the question by retrieving the needed phrase from the given content. Precise answering is the key role of a QA system. An ambiguity is developed when we need to answer a negative question with a positive reply. The negation words change the polarity of the sentence, and hence, the scope of negation words is notable. This has paved the way for studying the role of ‘negation’ in the natural language processing (NLP) task. The handling of these words is considered a major part of our proposed methodology. In this paper, we propose an algorithm to retrieve and replace the negation words present in the content and query. A comparative study is done for performing word embedding over these words using various state-of-the-art methods. In earlier works when handling the negation the semantics of the sentences are changed. Hence, in this paper we try to maintain the semantics through our proposed methodology. The updated content is embedded into the bi-directional long short-term memory (Bi-LSTM) and thus makes the retrieving of an answer for a question answer system easier. The proposed work has been carried over the Stanford Negation, and the SQuAD dataset with a higher precision value of 96.2% has been achieved in retrieving the answers that are given in the dataset.

     

The Esterase PfeE,the Achilles’ Heel in the Battle for Iron between Pseudomonas aeruginosa and Escherichia coli

Bacteria access iron, a key nutrient, by producing siderophores or using siderophores produced by other microorganisms. The pathogen Pseudomonas aeruginosa produces two siderophores but is also able to pirate enterobactin (ENT), the siderophore produced by Escherichia coli. ENT-Fe complexes are imported across the outer membrane of P. aeruginosa by the two outer membrane transporters PfeA and PirA. Iron is released from ENT in the P. aeruginosa periplasm by hydrolysis of ENT by the esterase PfeE. We show here that pfeE gene deletion renders P. aeruginosa unable to grow in the presence of ENT because it is unable to access iron via this siderophore. Two-species co-cultures under iron-restricted conditions show that P. aeruginosa strongly represses the growth of E. coli as long it is able to produce its own siderophores. Both strains are present in similar proportions in the culture as long as the siderophore-deficient P. aeruginosa strain is able to use ENT produced by E. coli to access iron. If pfeE is deleted, E. coli has the upper hand in the culture and P. aeruginosa growth is repressed. Overall, these data show that PfeE is the Achilles’ heel of P. aeruginosa in communities with bacteria producing ENT.     

Transcranial Magnetic Stimulation of the Supplementary Motor Area in the Treatment of Obsessive-Compulsive Disorder: A Multi-Site Study

Recently, strategies beyond pharmacological and psychological treatments have been developed for the management of obsessive-compulsive disorder (OCD). Specifically, repetitive transcranial magnetic stimulation (rTMS) has been employed as an adjunctive treatment in cases of treatment-refractory OCD. Here, we investigate six weeks of low frequency rTMS, applied bilaterally and simultaneously over the sensory motor area, in OCD patients in a randomized, double-blind placebo-controlled clinical trial. Twenty-two participants were randomly enrolled into the treatment (ACTIVE = 10) or placebo (SHAM = 12) groups. At each of seven visits (baseline; day 1 and weeks 2, 4, and 6 of treatment; and two and six weeks after treatment) the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) was administered. At the end of the six weeks of rTMS, patients in the ACTIVE group showed a clinically significant decrease in Y-BOCS scores compared to both the baseline and the SHAM group. This effect was maintained six weeks following the end of rTMS treatment. Therefore, in this sample, rTMS appeared to significantly improve the OCD symptoms of the treated patients beyond the treatment window. More studies need to be conducted to determine the generalizability of these findings and to define the duration of rTMS’ clinical effect on the Y-BOCS. Clinical Trial Registration Number (NCT) at www.clinicaltrials.gov: {"type":"clinical-trial","attrs":{"text":"NCT00616486","term_id":"NCT00616486"}}NCT00616486.     

Structural and magnetic properties of Li2O–Fe2O3 ceramic nanostructures

xLi₂O–(1−x)α-Fe₂O₃ (x=0.1, 0.3, 0.5, and 0.7) nanoparticle systems were successfully synthesized by mechanochemical activation of Li₂O and α-Fe₂O₃ mixtures for 0–12 h of ball milling time. The study aims at exploring the formation of magnetic oxide semiconductors at the nanoscale, which is of crucial importance for catalysis, sensing and electrochemical applications. X-ray powder diffraction (XRD), Mössbauer spectroscopy and magnetic measurements were used to study the phase evolution of xLi₂O–(1−x)α-Fe₂O₃ nanoparticle systems under the mechanochemical activation process. Rietveld refinement of the XRD patterns yielded the values of the particle size as function of composition and milling times and indicated the presence of Li-substituted hematite and tetra lithium iron oxide LiFeO₂, along with the formation of multiple phases for large x values and long milling times. The Mössbauer studies showed that the spectrum of the mechanochemically activated composites evolved from a sextet for hematite to sextets and a doublet upon duration of the milling process with lithium oxide. Magnetic measurements recorded at 5 K to room temperature (RT) in an applied magnetic field of 50,000 Oe showed that the magnetization of the milled samples is larger at low temperatures than at RT and increases with decreasing particle size. Zero field cooling measurements made possible the determination of the blocking temperatures of the specimens as function of ball milling time and evidenced the occurrence of superparamagnetism in the studied samples. This result correlates well with the observed presence of a quadrupole-split doublet in the Mössbauer spectra.     

Mycotoxin risk assessment for the purpose of setting international regulatory standards

The 2003 Council for Agricultural Science and Technology Mycotoxin report states that one 21st century goal is the development of uniform regulations worldwide for foodborne mycotoxin contamination. This study informs that endeavor by a risk assessment and economic analysis of two important mycotoxins: fumonisins and aflatoxins. The goals are to identify the nations that would be most heavily impacted by tighter mycotoxin regulations, examine costs and benefits as a function of regulatory stringency, and address risk-risk tradeoffs between health benefits and economic losses from compliance with those regulations. Among industrial nations, the United States would experience the heaviest economic losses from more precautionary mycotoxin standards. Environmental conditions in the developing world, however, are more conducive to mycotoxin accumulation in crops. Contrary to concerns expressed among policymakers, the less developed countries that would likely experience the greatest loss from tighter mycotoxin standards are not sub-Saharan African nations, but China and Argentina. If a fumonisin standard of 0.5 mg/kg were adopted worldwide, total export losses from fumonisins in corn may exceed 300 million dollars annually: 3-fold higher than if the less stringent U.S. standard of 2 mg/kg were adopted. Likewise, export losses from aflatoxins in peanuts may exceed 450 million dollars under the current EU regulatory standard of 4 microg/kg: almost 5-fold higher than if the U.S. standard of 20 microg/kg were adopted. Stricter standards are unlikely to improve health significantly. In developing nations such as China where hepatitis B and C are prevalent, tighter aflatoxin standards may increase health risks until improved control methods for aflatoxins are found, as high-quality crops may be exported instead of being consumed domestically.     

The effects of social category norms and stereotypes on explanations for intergroup differences.

A 2-stage model of the construction of explanations for differences between groups is presented. Category norms affect which of 2 groups becomes "the effect to be explained," and stereotypes shape attributions about that group. In 3 experiments, 288 participants wrote explanations for differences between gay and straight men. Explanations focused on gay men who were also judged to have more mutable attributes. However, these effects were not correlated. Participants focused explanations on straight men when explicitly instructed to do so (Experiment 1). Explanations focused on both groups equally when the gay men constituted the numerically larger sample, when gay men were more typical of the overarching category (i.e., people with AMS) than straight men, or when more straight men were described as performing the behavior (Experiment 2). Stereotype-consistent information prompted more essentialist references and fewer reconstructive references to gay men than did stereotype-inconsistent information (Experiment 3). The relevance of this model for theories of norms, stereotypes, and for the conduct of social science is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Folding and activity of the hammerhead ribozyme

The hammerhead is the smallest of the nucleolytic ribozymes, that undergo backbone cleavage by a transesterification reaction in the presence of magnesium ions. The RNA is induced to fold into its active conformation by the binding of metal ions in two stages. These generate domain 2, the scaffold on which the ribozyme is built, and domain 1, the active centre of the ribozyme. Further local structural rearrangement during the activation of the ribozyme is suggested by a number of crystal structures. The 10(5)-fold rate enhancement is probably brought about by a combination of metal-ion participation and stereochemical factors in the environment of the folded RNA structure.     

Perspektiven der Plasmamedizin

Prospects of plasma medicine: Applications of Tissue Tolerable Plasmas (TTP) Based on the current knowledge on the physical properties and biological effects of tissue tolerable plasma (ttp) potential perspectives of plasma medicine are discussed. Currently, the foundations for the following medical applications of ttp are developed by an interdisciplinary research team: Prevention and/or treatment of diseases such as chronic wounds, skin and mucosal infectious diseases, localized tumors, promotion of angiogenesis, and tissue ablation Inhibition and/or elimination of biofilms by prevention of biofilm development due to surface treatment and/or plasma steered application of antimicrobial active layers with drug delivery function on foreign objects implanted into humans (implantable prosthesis, contact lenses, stents etc.) as well as elimination of biofilms by direct action of ttp on surfaces and tissues (chronic wounds, tooth surface, prosthesis) promotion of the incorporation of implants into viable tissue by changing the surface of materials (hydrophobicity) Promotion of penetration of topically applied drugs with therapeutic results Assessment of veterinary indications Improved cleaning performance in reprocessing of medical devices by surface modification.     

Synthetic Fluids for High Capacity Traction Drives

A series of fluids having coefficients of traction in rolling contact devices higher by 30% or more than those of the best previously available oils have been developed. These fluids have good oxidation stability in the 300–350 F range, are compatible with standard engineering materials and have viscosity characteristics suitable for industrial or vehicular applications.

The screening test methods used for determination of coefficient of traction in the development of these fluids are described.