Use of Ficus Septica Leaf Extract for Biological Control of Anthracnose Disease in Carica Papaya Caused by Colletotrichum spp

The fig (Ficus septica) is a widespread wild plant whose leaf extract contains bioactive compounds with antifungal properties, including alkaloid and phenolic compounds, both of which are antioxidants. Colletothricum spp. is a pathogenic fungus found in cultivated plants that can cause anthracnose, a plant disease. Papaya (Carica papaya) is one of the cultivated plants that frequently displays symptoms of anthracnose disease caused by Colletothricum spp. The focus of this research was to determine whether F. septica leaf extract could inhibit the growth of Colletothricum spp. on C. papaya. The antifungal activity of F. septica leaf extract against Colletothricum spp. was measured using the well diffusion method. The extract concentrations, which were determined by measuring the extract’s MIC value, were 0.5%, 1%, 2%, 3%, 4% and 5% (b/v), with methanol and synthetic fungicides serving as controls. According to the findings, the MIC value of the F. septica leaf extract on Colletothricum spp. growth was 0.4%, with an inhibition zone of 2.37 mm. Meanwhile, the inhibition zones formed by the F. septica leaf extract treatment were 2.5 mm, 3.4 mm, 7.6 mm, 9.7 mm, 12.7 mm, and 13.5 mm, respectively, and 0 mm for the negative control and 30 mm for the positive control. According to the analysis of variance results, all of the treatments produced results that were significantly different from those of the negative control, and the 4% extract was the most effective in vitro. We conclude that F. septica crude leaf extract contains bioactive compounds with antifungal properties and it can be used as a safe alternative to control Carica papaya anthracnose disease. Keywords: anthracnose, Carica papaya, Colletothricum spp., Ficus septica

Rapid and Highly Selective Detection of Heavy Metal Ions in Drinking Water using Nanosensor Based Colorimetric Assay

Owing to excessive usage, over time, heavy metal ions have brought on serious environmental issues as well as health hazards in living systems. Sources of drinking watergetting contaminated by heavy metals is one of the most prominent concerns among these. Hence, constructing an accurate method for the determination of heavy metals in water bodies is of great importance. In the current context, several quantitative techniques like atomic absorption spectrometry, high-performance liquid chromatography and chemiluminescence are available for this purpose. However, these methods have certain drawbacks such as long assay time, high cost and the need of sophisticated instruments and well-trained personnel. Therefore, the development of a simple, cost effective and efficient method for the detection of heavy metal ions is desirable in order to delimit its harmful effects. This study is conducted with the aim of developing a nanosensor to account for this cause. Out of various nanomaterials used in sensing applications, silver nanoparticles (AgNPs) are particularly outstanding as they possess unique optical performance. AgNPs were synthesised by reduction of silver nitrate using hydroxylamine hydrochloride. Synthesized AgNPs were then surface functionalised with two distinct ligands on two separate occasions, namely, L-cysteine and 4-mercaptobenzoic acid (4-MBA). Both these ligands contain a thiol group which displays high affinity for Ag surfaces and a carboxyl group which can interact with the surrounding, or in this case, to act as a sensor formetal ions. These nanoprobes were tested against standards of various metal ions. The presence of Cd2+ induces the aggregation of L-cysteine functionalised AgNPs whereas 4-MBA functionalised AgNPs undergo aggregation in the presence of Cr3+ ions. In both these instances, AgNPs get linked together by “carboxylate-metal ion-carboxylate” coordinative couplings, resulting in a colour change from yellow to deep orange. The concentration of the respective metal ion in each case could be monitored by the colorimetric response obtained by UV-Vis spectroscopy or even naked eyes and the detection limit is as low as 1 ppm. This novel detection system could be successfully applied to determine Cd2+ and Cr3+in drinking water.Keywords: Silver nanoparticles, Cadmium ions, Chromium ions, Nanosensor, Colorimetr

Fluorescence spectroscopy characterization of turbine oil (Caltex Regal R&O 68) used in Samanala Dam hydropower plant in Sri Lanka

The energy crisis is a major issue not only in Sri Lanka but also globally. One of the major issues pertaining to this crisis is the extant use of nonrenewable sources such as oil, coal and natural gas. Hydro power is a major renewable energy source that can be used to generate the electricity requirements of Sri Lanka. It is necessary for a hydropower turbine to function efficiently without any failures to generate electricity. The lubricants used in gearboxes of turbines play a major role in the proper functioning of hydropower turbines. Here, researchers have studied spectroscopic differences of new and discarded Caltex Regal R & O 68 using Raman spectroscopy, Fourier Transform InfraRed (FTIR) spectroscopy and fluorescence spectroscopy. Among spectra obtained from above spectroscopic techniques, the spectra obtained from fluorescence spectroscopy had a significant difference between two lubricant samples. The highest fluorescence intensity was recorded in the fresh/ new oil sample while the lowest intensity was in the oil which was discarded by the hydro turbines. Additionally, in this study, it was revealed how fluorescence intensity of turbine oil (Caltex Regal R&O 68) used in Samanala hydropower plant station varies with different temperatures 100 °C, 120 °C, 140 °C, and 200 °C. Moreover, 1-Naphthalenamine, N – phenyl was identified as the fluorophore used in Caltex Regal R&O 68 lubricant. Therefore, the fluorescence technique can be used as a tool for monitoring the quality of  hydropower turbine oils. KEYWORDS: Oil degradation, Antioxidants, Fluorescence intensity, Renewable energy, Fluorophor

Mapping and ablation of atrial tachyarrhythmias : from signal to substrate

Biosense Webster/Johnson & Johnson Medical BV, St Jude Medical Nederland BV, Guidant Nederland BV, Boston Scientific Nederland, Merck, Sharp & Dome, Bard Electrophysiology, Philips Medical Systems, AstraZeneca BV, Schering Plough, Siemens, Servier, Astellas Pharmas, Toshiba Medical Systems Nederland BV, Medtronic BV and Vitatron.UBL - phd migration 201

Direction- and rate-dependent fractionation during atrial fibrillation persistence: Unmasking cardiac anisotropy?

This human case is the first to illustrate morphological manifestations of direction- and rate-dependent anisotropic conduction in high-resolution unipolar atrial potentials. Premature impulses induced low-amplitude, fractionated extracellular potentials with exceptionally prolonged durations in a 76-year old longstanding persistent patient with atrial fibrillation (AF), demonstrating direction-dependency of anisotropic conduction. An increased pacing frequency induced presence of similar fractionated potentials, reflecting rate-dependent anisotropy and inhomogeneous, slow conduction. Pacing with different rates and from different sites could aid in identifying nonuniform anisotropic tissue and thus the substrate of AF

Human metapneumovirus: Mechanisms and molecular targets used by the virus to avoid the immune system

Indexación: Scopus.This work was supported by Comisión Nacional de Investigación Científica y Tecnolígica (CONICYT) N◦21151028 and FONDECYT (N◦1070352 and N◦1170964) and the Millennium Institute on Immunology and Immunotherapy (P09/016-F).Human metapneumovirus (hMPV) is a respiratory virus, first reported the year 2001. Since then, it has been described as one of the main etiological agents that causes acute lower respiratory tract infections (ALRTIs), which is characterized by symptoms such as bronchiolitis, wheezing and coughing. Susceptible population to hMPV-infection includes newborn, children, elderly and immunocompromised individuals. This viral agent is a negative-sense, single-stranded RNA enveloped virus, that belongs to the Pneumoviridae family and Metapneumovirus genus. Early reports-previous to 2001-state several cases of respiratory illness without clear identification of the responsible pathogen, which could be related to hMPV. Despite the similarities of hMPV with several other viruses, such as the human respiratory syncytial virus or influenza virus, mechanisms used by hMPV to avoid the host immune system are still unclear. In fact, evidence indicates that hMPV induces a poor innate immune response, thereby affecting the adaptive immunity. Among these mechanisms, is the promotion of an anergic state in T cells, instead of an effective polarization or activation, which could be induced by low levels of cytokine secretion. Further, the evidences support the notion that hMPV interferes with several pattern recognition receptors (PRRs) and cell signaling pathways triggered by interferon-associated genes. However, these mechanisms reported in hMPV are not like the ones reported for hRSV, as the latter has two non-structural proteins that are able to inhibit these pathways. Several reports suggest that viral glycoproteins, such as G and SH, could play immune-modulator roles during infection. In this work, we discuss the state of the art regarding the mechanisms that underlie the poor immunity elicited by hMPV. Importantly, these mechanisms will be compared with those elicited by other common respiratory viruses. © 2018 Frontiers Media S.A. All rights reserved.https://www.frontiersin.org/articles/10.3389/fimmu.2018.02466/ful

An Experimental Study of Bubble Rise Characteristics in non – Newtonian (Power-Law) Fluids

Air bubbles are used in chemical, biochemical, environmental, food process such as sugar industries for improving the heat and mass transfer. In particular, the bubble rise characteristics in massecuite - a fluid made from sugar crystals and sugar syrup have a great influence on vacuum pan operation which is an important process for the production of raw sugar in sugar industries. An experimental study of the bubble rise characteristics in xanthan gum solutions, a non-Newtonian (Power-Law) massecuite equivalent fluid are presented in this paper. The main characteristics, i.e. the bubble velocity, the bubble trajectory, and the drag relationship were investigated as a function of volume of air bubbles. The bubble rise velocity and trajectory were measured using a combination of non-intrusive (high speed photographic) method and digital image processing. The parameters that significantly affect the rise of air bubble are identified. The effect of different bubble volumes and liquid heights on the bubble rise velocity and bubble trajectory are analysed and discussed. A relationship between the Reynolds number and the drag coefficient is presented and discussed

Catheter ablation of right ventricular outflow tract tachycardia using contact force guidance

Outflow tract tachycardias (OTT) originating from the right or left ventricular outflow tract are thought to be benign. However, symptoms can be disabling and deterioration of left ventricular function may occur with a high arrhythmia burden. Catheter ablation has a high acute success rate of up to 90 %, but recurrences are not uncommon [1, 2]. Novel catheter designs, and mapping and ablation technologies aim to improve procedural outcome, lower the complication rate, and increase the long-term success rate [3]. The TactiCath (R) catheter (TactiCath (R), Endosense, SA Meyrin/Geneva, Switzerland, distributed by Biotronik, Berlin, Germany) is a contact force (CF) sensing radiofrequency ablation catheter that provides real-time assessment of tip-to-tissue CF during ablation [4]. Until now, it has only been used in ablation of supraventricular tachycardias, mainly atrial fibrillation. In this report, we describe the case of a patient who underwent successful ablation of right ventricular OTT and ventricular premature beats (VPBs) using CF guidance. To the best of our knowledge, this is the first case ever described of OTT ablation using CF with the TactiCath (R) catheter

The future of tourism in light of increasing natural disasters.

Purpose: This paper aims to highlight the need to better understand the determinants of adopting (more) collaborative, integrated approaches in strategic destination management plans and operational business procedures which is to improve destination and business resilience towards the growing frequency, increasing number and accelerating impacts of natural disasters around the world. Design/methodology/approach: The paper reviews literature on the topic of tourism planning, development and management in light of natural disasters. Findings: The paper pinpoints a number of factors that hamper the adoption of a (better) integrated and (more) collaborative framework of disaster and destination management among tourism stakeholders. It further proposes how these factors can at least partially be addressed and highlights the role of scholarly research in this endeavour. Originality/value: The paper highlights the determinants of adopting more integrated and collaborative approaches to managing natural disasters by individual tourism businesses and entire tourist destinations and proposes how these can be harnessed