Pointwise Mutual Information Based Metric and Decoding Strategy for Faithful Generation in Document Grounded Dialogs

A major concern in using deep learning based generative models for document-grounded dialogs is the potential generation of responses that are not \textit{faithful} to the underlying document. Existing automated metrics used for evaluating the faithfulness of response with respect to the grounding document measure the degree of similarity between the generated response and the document's content. However, these automated metrics are far from being well aligned with human judgments. Therefore, to improve the measurement of faithfulness, we propose a new metric that utilizes (Conditional) Point-wise Mutual Information (PMI) between the generated response and the source document, conditioned on the dialogue. PMI quantifies the extent to which the document influences the generated response -- with a higher PMI indicating a more faithful response. We build upon this idea to create a new decoding technique that incorporates PMI into the response generation process to predict more faithful responses. Our experiments on the BEGIN benchmark demonstrate an improved correlation of our metric with human evaluation. We also show that our decoding technique is effective in generating more faithful responses when compared to standard decoding techniques on a set of publicly available document-grounded dialog datasets.Comment: EMNLP 202

Safety evaluation of chromium picolinate in experimental rats

Background: Chromium, an essential trace mineral plays an important role in the metabolism of carbohydrate, fat and proteins. Chromium picolinate (Cr.Pic) is used in alternative medicine to treat chromium deficiency. Though Cr.Pic is increasingly used to treat diabetes and obesity, studies on its safety profile is limited.Methods: Acute toxicity study was conducted by oral administration of Cr.Pic (2000 mg/kg body weight). The animals were maintained another 14 days with once a day observation. For sub-chronic studies, test groups were treated with Cr.Pic 10 mg/kg/day for 90 days. Tests for hepatic and renal function were conducted. Effect of Cr.Pic on behavioural changes and motor co-ordination was done on every week. Histopathological studies were conducted on day 90 at the end of the experiment.Results: Acute toxicity study of Cr.Pic showed no signs of toxicity and mortality. Absence of any behavioural alteration or mortality during the period of 14 days indicates that Cr.Pic has no latent effect. Similar results were obtained with sub-chronic studies suggesting safety of Cr.Pic. Cr.Pic treated groups showed no changes in learning and motor co-ordination compared to the untreated group. No gross histopathological changes were seen in any group indicating safety of Cr.Pic.Conclusions: The present study conferred safety profile of Cr.Pic from normal results obtained in hepatic function, renal function, behavioural and histopathological studies, suggesting its safety

Repercussion of biofilm and antibiotic resistance in ventilator associated pneumonia

Background: Ventilator associated pneumonia contributes nearly half of all cases of hospital-acquired pneumonia. Drug resistance among ventilator associated pneumonia has obligation of device withdrawal in order to achieve clinical and microbiological cure. Aim of the study was to determine the relationship between antibiotic resistance of Endotracheal tube biofilm and pulmonary pathogens in ventilator-associated pneumonia.Methods: A descriptive analytical study of 100 clinically suspected VAP patients was done. Patients were divided into group-I and Group-II based on intubation duration for 1-5 days and 6-10 days respectively. Endotracheal aspirate (ETA) was collected from clinically diagnosed cases and processed as per standard microbiological techniques. Bacterial counts ≥106 CFU/ml for quantitative cultures was considered significant. Biofilm production was detected by tissue culture plate, tube method and Congo red method. Multi-variant analysis was done to find out the association of the various factors.Results: Klebsiella pneumoniae was the predominant bacteria isolated followed by Acinetobacter baumannii. 45% of Gram negative bacteria were β lactamase producers. In Biofilm production by tissue culture method, 72% of the isolates showed either strong or moderate biofilm formation. Multivariate analysis revealed that bacteria isolated from VAP occurring after 5 days of mechanical ventilation among prior antibiotic-treated patients were resistant to all the antibiotics tested.Conclusions: Bacterial aetiology, biofilm formation and drug resistance has ramification on outcome of ventilator associated pneumonia. Hence, advised that it is crucial to remove ET tube in regular interval to prevent biofilm formation and sequential cultures to obtain the microbiological information which enables better patient care.

Fiber guiding at the Dirac frequency beyond photonic bandgaps

Light trapping within waveguides is a key practice of modern optics, both scientifically and technologically. Photonic crystal fibers traditionally rely on total internal reflection (index-guiding fibers) or a photonic bandgap (photonic-bandgap fibers) to achieve field confinement. Here, we report the discovery of a new light trapping within fibers by the so-called Dirac point of photonic band structures. Our analysis reveals that the Dirac point can establish suppression of radiation losses and consequently a novel guided mode for propagation in photonic crystal fibers. What is known as the Dirac point is a conical singularity of a photonic band structure where wave motion obeys the famous Dirac equation. We find the unexpected phenomenon of wave localization at this point beyond photonic bandgaps. This guiding relies on the Dirac point rather than total internal reflection or photonic bandgaps, thus providing a sort of advancement in conceptual understanding over the traditional fiber guiding. The result presented here demonstrates the discovery of a new type of photonic crystal fibers, with unique characteristics that could lead to new applications in fiber sensors and lasers. The Dirac equation is a special symbol of relativistic quantum mechanics. Because of the similarity between band structures of a solid and a photonic crystal, the discovery of the Dirac-point-induced wave trapping in photonic crystals could provide novel insights into many relativistic quantum effects of the transport phenomena of photons, phonons, and electrons

Exploration of Anti-HIV Phytocompounds against SARS-CoV-2 Main Protease: Structure-Based Screening, Molecular Simulation, ADME Analysis and Conceptual DFT Studies

The ever-expanding pandemic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has gained attention as COVID-19 and caused an emergency in public health to an unmatched level to date. However, the treatments used are the only options; currently, no effective and licensed medications are available to combat disease transmission, necessitating further research. In the present study, an in silico-based virtual screening of anti-HIV bioactive compounds from medicinal plants was carried out through molecular docking against the main protease (Mpro) (PDB: 6LU7) of SARS-CoV-2, which is a key enzyme responsible for virus replication. A total of 16 anti-HIV compounds were found to have a binding affinity greater than −8.9 kcal/mol out of 150 compounds screened. Pseudohypericin had a high affinity with the energy of −10.2 kcal/mol, demonstrating amino acid residual interactions with LEU141, GLU166, ARG188, and GLN192, followed by Hypericin (−10.1 kcal/mol). Moreover, the ADME (Absorption, Distribution, Metabolism and Excretion) analysis of Pseudohypericin and Hypericin recorded a low bioavailability (BA) score of 0.17 and violated Lipinski’s rule of drug-likeness. The docking and molecular simulations indicated that the quinone compound, Pseudohypericin, could be tested in vitro and in vivo as potent molecules against COVID-19 disease prior to clinical trials.This was also supported by the theoretical and computational studies conducted. The global and local descriptors, which are the underpinnings of Conceptual Density FunctionalTheory (CDFT) have beenpredicted through successful model chemistry, hoping that they could be of help in the comprehension of the chemical reactivity properties of the molecular systems considered in this study.Fil: Murali, Mahadevamurthy. University Of Mysore; IndiaFil: Gowtham, Hittanahallikoppal Gajendramurthy. Nrupathunga University; IndiaFil: Shilpa, Natarajamurthy. University Of Mysore; IndiaFil: Krishnappa, Hemanth Kumar Naguvanahalli. University Of Mysore; IndiaFil: Ledesma, Ana Estela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Centro de Investigación en Biofísica Aplicada y Alimentos. - Universidad Nacional de Santiago del Estero. Centro de Investigación en Biofísica Aplicada y Alimentos; ArgentinaFil: Jain, Anisha S.. University Of Mysore; IndiaFil: Shati, Ali A.. King Khalid University; Arabia SauditaFil: Alfaifi, Mohammad Y.. Vacsera Holding Company; EgiptoFil: Elbehairi, Serag Eldin I.. Jss Academy Of Higher Education And Research; IndiaFil: Achar, Raghu Ram. Pirogov Russian National Research Medical University; RusiaFil: Silina, Ekaterina. Universitat de Les Illesbalears; EspañaFil: Stupin, Victor. Centro de Investigaciónen Materiales Avanzados; MéxicoFil: Ortega Castro, Joaquín. Jss Academy Of Higher Education And Research; IndiaFil: Frau, Juan. Universitat de Les Illesbalears; EspañaFil: Flores Holguín, Norma. Centro de Investigaciónen Materiales Avanzados; MéxicoFil: Amruthesh, Kestur Nagaraj. University Of Mysore; IndiaFil: Shivamallu, Chandan. Jss Academy Of Higher Education And Research; IndiaFil: Kollur, Shiva Prasad. University Of Mysore; IndiaFil: Glossman Mitnik, Daniel. Centro de Investigaciónen Materiales Avanzados; Méxic

Pairing symmetry and properties of iron-based high temperature superconductors

Pairing symmetry is important to indentify the pairing mechanism. The analysis becomes particularly timely and important for the newly discovered iron-based multi-orbital superconductors. From group theory point of view we classified all pairing matrices (in the orbital space) that carry irreducible representations of the system. The quasiparticle gap falls into three categories: full, nodal and gapless. The nodal-gap states show conventional Volovik effect even for on-site pairing. The gapless states are odd in orbital space, have a negative superfluid density and are therefore unstable. In connection to experiments we proposed possible pairing states and implications for the pairing mechanism.Comment: 4 pages, 1 table, 2 figures, polished versio

Safety of Postoperative Administration of Human Urinary Trypsin Inhibitor in Lung Cancer Patients with Idiopathic Pulmonary Fibrosis

Patients with idiopathic pulmonary fibrosis (IPF) undergoing pulmonary resection for lung cancer carry risks of acute exacerbations of IPF (AE) postoperatively. Currently, agents which may attenuate AE are actively sought. Urinary trypsin inhibitor, ulinastatin, is a synthetic glycoprotein which may potentially inhibit various inflammatory factors associated with the development and progression of IPF. The present study was done to evaluate the effects of administration of high dose ulinastatin in lung cancer patients with IPF immediately following lung resection.Patients with IPFs radiologically diagnosed on high resolution CT, and histologically diagnosed resectable lung cancers, were eligible for the study. The effects of escalating doses of ulinastatin 3×10(5), 6×10(5), and 9×10(5) units/body/day, administered postoperatively for 3 days were evaluated. The endpoints were safety and feasibility.Nine patients were evaluated, in cohorts of 3 patients per dosage. Postoperative follow up ranged from 3 to 12 months (median 9 months). The postoperative courses were uneventful in all patients. No subjective adverse events such as abdominal symptoms or skin rashes, or objective adverse events as per serum laboratory tests, such as liver or kidney dysfunctions potentially attributable to ulinastatin administration were observed. AE was seen in one patient at 3 months after surgery, but since this occurred shortly after administration of chemotherapy, it was considered to be attributable to the chemotherapy rather than surgery.Ulinastatin administration after lung resection in lung cancer patients with IPF was considered to be safe and feasible. Further study is planned at the highest dose of this study to evaluate efficacy.UMIN.ac.jp/ctr/UMIN000002410