Anatomizing extracellular polymer of Calothrix desertica with its anti-oxidation and anti-nutrient profiling

Calothrix desertica having a semilunar apical heterocyst is proficient at excreting 1.2 g/L of extracellular polymers (EPsC) in 45 days. The refined EPsC constitutes 430 mg/g of glycogen, 390 mg/g of protein, and 14.6 mg/g of glycoproteins (GPs). The glycoprotein estimation of EPsC was performed by two step hydrolysis methods with H2SO4. The peak between 10 mAU to 20 mAU in HPLC, 1400 cm-1 to 1700 cm-1 in FTIR, and 40kDa- 35kDa bands in SDS-PAGE authenticates the presence of glycoproteins in the EPsC. The EPsC agglomerate of 1000 nm to 3000 nm size with a Zeta potential of -20 mV to 5 mV was determined using DLS. Further EPsC of nanosizes of 30 nm to 150 nm in 50,000 X and 20 nm to 40 nm in 60,000 X was measured using FE- SEM. The DPPH assay and H2O2 scavenging assay showed 73.1% and 70.8% of anti-oxidant activity in EPsC, which is coequally efficient as standard gallic acid. EPsC biopolymer can also be used as a potential reducing agent, as per the anti-nutrient activity studies

Knowledge, attitude and practices of postgraduates, interns and nurses, on adverse drug reaction reporting in a tertiary care hospital: a comparative study

Background: Pharmacovigilance is multidisciplinary field of the detection, assessment, understanding, and prevention of adverse drug reactions (ADRs). The incidences of ADRs about 95% are undocumented worldwide. However, there is a lack of information on ADR burden in developing countries due to lack of resources, infrastructure, and expertise.Methods: A cross-sectional questionnaire-based study was conducted on 90 staff nurses 90interns and 90 postgraduates. The validated questionnaire contained items to check knowledge including 7 questions, 9 questions to analyze attitude and 5 for practices. Comparison between knowledge, attitude and practice data obtained from resident doctors and nurses was performed using Chi square test.Results: A total of 270 healthcare professionals participated in the study. In our study the participants had good knowledge regarding the purpose of monitoring and reporting ADRs etc. The result shows that health care professionals felt reporting of ADRs is a professional obligation and all ADRs should be reported. There was no significant difference in the knowledge and attitude between interns and nurses but few questionnaires show significant variations between post graduate and staff nurse. The practice of ADR reporting was significantly higher in postgraduate compared to nurses.Conclusions: This study concluded that post graduate, intern and staff nurse had good knowledge and positive attitude towards pharmacovigilance and ADR reporting, but unfortunately the actual practice of ADR reporting is still deficient among staff nurse and intern. This can be improved by adequate training and motivation

Analysis of the Stability of Openings Excavated in Anisotropic Rocks

Openings excavated in rocks with anisotropic strength are often affected by serious instability, related to slip along the weakness planes. The Jaeger criterion, which is a discontinuous approach, is widely used in the mining and oil and gas industry, because is based on well-known rock strength parameters. However, this model cannot capture features related to the stability of openings drilled in some anisotropic rocks with the combined effect of the in situ state of stress. The Hoek & Brown criterion, adapted to anisotropic rocks, is a continuous criterion that can describe the complex behavior of different types of anisotropy exhibited by rock material. Here we interpreted the results of triaxial tests carried out on a shale and we defined the parameters of the Jaeger criterion and the modified Hoek & Brown criterion. We investigated the stability of boreholes drilled in this shale by varying the in situ state of stress and we compared the results of the two criteria. We found that the Hoek & Brown criterion can appropriately describe the behavior of this shale and can predict more accurately the width of the instability of openings excavated in different conditions

Experimental and numerical analyses of magnesium alloy hot workability

AbstractDue to their hexagonal crystal structure, magnesium alloys have relatively low workability at room temperature. In this study, the hot workability behavior of cast-extruded AZ31B magnesium alloy is studied through hot compression testing, numerical modeling and microstructural analyses. Hot deformation tests are performed at temperatures of 250 °C to 400 °C under strain rates of 0.01 to 1.0 s−1. Transmission electron microscopy is used to reveal the presence of dynamic recrystallization (DRX), dynamic recovery (DRY), cracks and shear bands. To predict plastic instabilities during hot compression tests of AZ31B magnesium alloy, the authors use Johnson–Cook damage model in a 3D finite element simulation. The optimal hot workability of magnesium alloy is found at a temperature (T) of 400 °C and strain rate (ε˙) of 0.01 s−1. Stability is found at a lower strain rate, and instability is found at a higher strain rate

Energetics Based Spike Generation of a Single Neuron: Simulation Results and Analysis

Existing current based models that capture spike activity, though useful in studying information processing capabilities of neurons, fail to throw light on their internal functioning. It is imperative to develop a model that captures the spike train of a neuron as a function of its intracellular parameters for non-invasive diagnosis of diseased neurons. This is the first ever article to present such an integrated model that quantifies the inter-dependency between spike activity and intracellular energetics. The generated spike trains from our integrated model will throw greater light on the intracellular energetics than existing current models. Now, an abnormality in the spike of a diseased neuron can be linked and hence effectively analyzed at the energetics level. The spectral analysis of the generated spike trains in a time–frequency domain will help identify abnormalities in the internals of a neuron. As a case study, the parameters of our model are tuned for Alzheimer’s disease and its resultant spike trains are studied and presented. This massive initiative ultimately aims to encompass the entire molecular signaling pathways of the neuronal bioenergetics linking it to the voltage spike initiation and propagation; due to the lack of experimental data quantifying the inter dependencies among the parameters, the model at this stage adopts a particular level of functionality and is shown as an approach to study and perform disease modeling at the spike train and the mitochondrial bioenergetics level

Radiofrequency ablation for Barrett's oesophagus related neoplasia with the 360 Express catheter: initial experience from the United Kingdom and Ireland—preliminary results

BACKGROUND: Radio-frequency ablation (RFA) for Barrett's oesophagus (BE)-related neoplasia is currently used after endoscopic resection of visible neoplasia. The HALO 360 balloon has been used to ablate long segment BE. The Barrx™ 360 Express RFA self-sizing catheter ('RFA Express') may potentially allow quicker ablation times and improved treatment outcomes. The aim of this paper is to present real world data on the use of the 360 Express Device. METHODS: Centres in the UK and Ireland submitted cases where the RFA Express was used. The primary outcome was regression of BE at 3 months. Secondary outcomes were the rate of symptomatic stricture formation and resolution of intestinal metaplasia (CR-IM) and dysplasia (CR-D) at End of Treatment (EoT). RESULTS: 11 centres submitted 123 consecutive patients. 112 had a follow up endoscopy. The median age was 67 years (IQR 62-75). 3 dosimetries were used. The mean reduction in Circumferential (C) length was 78% ± 36 and mean reduction in Maximal length (M) was 55% ± 36. 17 patients (15%) developed strictures requiring dilation. There was a higher rate of stricture formation when the 12 J energy was used (p < 0.05). 47 patients had EoT biopsies, 40 (85%) had CR-D and 34(76%) had CR-IM. CONCLUSIONS: The RFA 360 Express catheter shows reduction in length of baseline BE at 3 months after index treatment, and eradication of intestinal metaplasia and dysplasia at 12 months similar to other studies with earlier devices. It appears that the symptomatic stricture rate is slightly higher than previous series with the HALO 360 catheter. This study was performed as part of the HALO registry and has been approved by the Research Ethics Committee - MREC Number 08/H0714/27 Local project reference 08/0104 Project ID 15,033 IRAS Number 54678 EudraCT 2009-015980-1. Registered on ISRCTN as below: ISRCTN93069556. https://doi.org/10.1186/ISRCTN93069556