Gated Detection Measurements of Phosphorescence Lifetimes

A low-cost, gated system for measurements of phosphorescence lifetimes is presented. An extensive description of the system operating principles and metrological characteristics is given. Remarkably, the system operates without optical filtering of the LED excitation source. A description of a practical system is also given and its performance is discussed. Because the device effectively suppresses high-level background fluorescence and scattered light, it is expected to find wide-spread application in bioprocess, environmental and biomedical fields

The impact of non-steroidal anti-inflammatory drugs use in elderly cardiovascular patients: an observational study from tertiary care in South India

Background: Long-term use of NSAIDs, by patients having cardiovascular conditions, has shown to increase the risk of cardiovascular events and increased risk of death. Hence, the study was conducted to determine the complications related to NSAID use by the elderly patients with cardiovascular disease (CVD).Methods: The study was a single-center prospective observational study conducted November 2017 to October 2018. Elderly patients (>60 years) suffering from various CVDs and reported NSAID intake daily for at least one month were included. A questionnaire included demographic, treatment related history and complete details of NSAIDs intake including nature, dose, indication, source etc. The same questionnaire was again filled at the end of one-year follow-up.Results: A total of 100 participants were included in the study. The mean age was 72±8.6 years. Majority of the patients (93%) had hypertension, and 69% of the patient had previous MI.  Five NSAIDs (diclofenac, ibuprofen, mefenamic acid, naproxen, and ketorolac) were used routinely. At least one over the counter NSAID used was reported by 86%, 57% were prescribed at least one NSAIDs by their orthopaedics and physicians. At the end of 1-year follow-up, authors found that 71% had MI (2% increase), 4% developed reinfarction, 20% had severe left ventricular failure (4% increase), 7% had atrial fibrillation (1% increase), and 2% patients died and 63% patients reported raise in systolic blood pressure by 5mmHg.Conclusions: High prevalence of concomitant NSAID use among elderly CVD patients, which might be contributing towards increase in CVS morbidity and mortality

A Novel Method for Ultrasonic Imaging of Flaws in Coarse Grain Austenitic Stainless Steels

Ultrasonic detection and imaging of flaws in thick coarse grained austenitic stainless steel components is challenging due to very high scattering. Spectral and wavelet transform based methods have been traditionally applied to reduce the noise to detect flaws. We propose a novel ensemble empirical mode decomposition based signal processing method for adaptive detection of flaws in coarse grained austenitic stainless steel. We have analyzed ultrasonic signals obtained from stainless steel specimens of different grain size (30-200 µm) with and without flaws. The ultrasonic signals lie in two different scattering regimes with wavelength to grain size ratio of 1.8 (near stochastic scattering) to 3 (far Rayleigh scattering). The analysis gave an idea to use particular numbers of intrinsic mode functions (IMFs) in conjunction with minimization approach for the reconstruction of ultrasonic signal. We have verified the usefulness of this method by analyzing the signals obtained from 200 µm grain size specimen with artificial defects. The proposed method has been successfully employed for adaptive detection of flaws in a 50 mm thick coarse grain austenitic stainless steel specimen and for imaging of flaws

Vector Quantization Methods for Access Point Placement in Cell-Free Massive MIMO Systems

We examine the problem of uplink cell-free access point (AP) placement in the context of optimal throughput. In this regard, we formulate two main placement problems, namely the sum rate and minimum rate maximization problems, and discuss the challenges associated with solving the underlying optimization problem with the help of some simple scenarios. As a practical solution to the AP placement problem, we suggest a vector quantization (VQ) approach. The suitability of the VQ approach to cell-free AP placement is investigated by examining three VQ-based solutions. First, the standard VQ approach, that is the Lloyd algorithm (using the squared error distortion function) is described. Second, the tree-structured VQ (TSVQ), which performs successive partitioning of the distribution space is applied. Third, a probability density function optimized VQ (PDFVQ) procedure is outlined, which enables efficient, low complexity, and scalable placement, and is aimed at a massive distributed multiple-input-multiple-output (MIMO) scenario. While the VQ-based solutions do not solve the cell-free AP placement problems explicitly, numerical experiments show that their sum and minimum rate performances are good enough, and offer a good starting point for gradient-based optimization methods. Among the VQ solutions, PDFVQ, with advantages over the other VQ methods, offers a good trade-off between sum and minimum rates.Comment: This work has been submitted to the IEEE for possible publication. Copyright may be transferred without notice, after which this version may no longer be accessibl

Ratiometric Alcohol Sensor based on a Polymeric Nile Blue

We present a sterilizable ratiometric fluorescent ethanol sensor with sensitivity over a wide range (0-100%) of ethanol concentration v/v. The sensor is composed of a near infra red fluorescent solvatochromic dye, nile blue methacrylamide polymerized into a polyethylene (glycol) dimethacrylate matrix. The dye can typically exhibit two or more wavelength dependent shifts in the fluorescence intensities based on its different micropolar environments. Two different concentrations of the nile blue methacrylamide dye were prepared and polymerized into homogenous films. The fluorescence properties of the two different films were investigated with a view to determining their ethanol sensing capabilities. The sensor was immersed in a water-ethanol solvent mixture. Excitation of the dye was performed at 470 nm. The range of emission wavelengths was 480-800 nm. The ratio of the fluorescence intensities at 620 nm and 554 nm was obtained for ethanol concentrations varying from 0-100% and the calibration curve of the ratiometric fluorescence intensities over the entire concentration range of ethanol was plotted. A ratiometric intensity change of over 33% has been obtained for pure ethanol compared to that obtained for pure water. The sensor response was rapid (≤10 minutes). The sterilizable ethanol sensor exhibits good potential for on-line monitoring of the ethanol generated in an LB fermentation chamber

Purple urine bag syndrome- changing hue!

Purple Urine Bag Syndrome (PUBS) is a unique disease entity characterised by purple discoloration of urine secondary to recurrent urinary tract infections with indigo and indirubin producing bacteria and is predominantly seen in constipated, chronically debilitated and catheterised women with alkaline urine. This syndrome indicates underlying recurrent urinary tract infections (UTIs) associated with higher incidence of mortality and morbidity than urinary tract infection alone without this occurrence. This article is about an elderly hypothyroid woman with PUBS and reviews the need to be aware of this entity

An Analysis of Global High Technology Leadership and the Role of Governmental Incentives

The United States has long been considered a pioneer in emerging technologies. But there is an abundance of literature to document that other nations are catching up and that developing nations adopt advanced technologies by leapfrogging state of the art technology platforms. Countries such as Japan, Korea and more recently China, have emerged as contenders for technology leadership in various areas. In this paper, we first analyze the literature to identify the key factors that determine global technology leadership. Based on the literature, we develop a model to analyze the relationship between these factors and technology leadership. In addition, we propose that government support, such as incentives and expenditure on R&D etc., impact this relationship and strengthen it. We use panel data analysis to test this relationship and our findings indicate that R&D and main science and technology indicators (MSTI) are significant determinants of technology leadership. This work presents several implications and a path forward for global technology leadership

Examining the influence of Moral Foundations on Polarization in Social Media Discourse: A context of vigilantism

In August 2022, Kyle Rittenhouse\u27s vigilantism in Kenosha, Wisconsin, resulted in two fatalities and one injury, sparking heightened public security concerns and eliciting intense moral reactions. These moral impulses tend to contribute to extreme judgments of right or wrong, thereby fostering polarization on social media. The phenomenon of polarization, recognized as a component of social cybersecurity, has recently gained attention. This study explores the impact of five Moral Foundations on polarization following vigilantism, utilizing moral foundation theory and vector autoregression (VAR) in the analysis of social media discourse. Our findings reveal that these Moral Foundations significantly influence polarization dynamics. This insight holds implications for both research and the development of practical strategies for managing the societal consequences of polarization on social media

Comparisons of optically monitored small-scale stirred tank vessels to optically controlled disposable bag bioreactors

<p>Abstract</p> <p>Background</p> <p>Upstream bioprocesses are extremely complex since living organisms are used to generate active pharmaceutical ingredients (APIs). Cells in culture behave uniquely in response to their environment, thus culture conditions must be precisely defined and controlled in order for productivity and product quality to be reproducible. Thus, development culturing platforms are needed where many experiments can be carried out at once and pertinent scale-up information can be obtained.</p> <p>Results</p> <p>Here we have tested a High Throughput Bioreactor (HTBR) as a scale-down model for a lab-scale wave-type bioreactor (CultiBag). Mass transfer was characterized in both systems and scaling based on volumetric oxygen mass transfer coefficient (k_La) was sufficient to give similar DO trends. HTBR and CultiBag cell growth and mAb production were highly comparable in the first experiment where DO and pH were allowed to vary freely. In the second experiment, growth and mAb production rates were lower in the HTBR as compared to the CultiBag, where pH was controlled. The differences in magnitude were not considered significant for biological systems.</p> <p>Conclusion</p> <p>Similar oxygen delivery rates were achieved in both systems, leading to comparable culture performance (growth and mAb production) across scales and mode of mixing. HTBR model was most fitting when neither system was pH-controlled, providing an information-rich alternative to typically non-monitored mL-scale platforms.</p

Great Divisions: The Evolution of Polarization During the Man-made Emergency of January 6, 2021.

Polarization, which refers to the formation of two opposing groups based on the users' beliefs and opinions, has a growing body of literature. However, social media polarization differs from offline polarization in that beliefs change almost instantaneously on social media as a result of events unfolding. We investigate the uses of social media communication that has resulted in polarized opinions among individuals prior to, during, and after the January 6th Capitol riots. Analyses of the dominant narratives on Twitter surrounding the incident reveal a high level of polarization throughout the unfolding of the event, with increased polarization possibly attributable to the onset of the crisis. We also observed that polarization is a dynamic phenomenon: as an event unfolds, polarization changes, and knowing how it changes is important for timely crisis resolution. We propose three measures of polarization that could be used to examine polarization accurately during a crisis