Inexpensive Methodology Research Articles

Simplified Method for Kinetic and Thermodynamic Screening of Cardiotonic Steroids through the K+-Dependent Phosphatase Activity of Na+/K+-ATPase with Chromogenic pNPP Substrate.

The antitumor effect of cardiotonic steroids (CTS) has stimulated the search for new methods to evaluate both kinetic and thermodynamic aspects of their binding to Na+/K+-ATPase (IUBMB Enzyme Nomenclature). We propose a real-time assay based on a chromogenic substrate for phosphatase activity (pNPPase activity), using only two concentrations with an inhibitory progression curve, to obtain the association rate (kon ), dissociation rate (koff ), and equilibrium (Ki ) constants of CTS for the structure-kinetics relationship in drug screening. We show that changing conditions (from ATPase to pNPPase activity) resulted in an increase of Ki of the cardenolides digitoxigenin, essentially due to a reduction of kon In contrast, the Ki of the structurally related bufadienolide bufalin increased much less due to the reduction of its koff partially compensating the decrease of its kon When evaluating the kinetics of 15 natural and semisynthetic CTS, we observed that both kon and koff correlated with Ki (Spearman test), suggesting that differences in potency depend on variations of both kon and koff A rhamnose in C3 of the steroidal nucleus enhanced the inhibitory potency by a reduction of koff rather than an increase of kon Raising the temperature did not alter the koff of digitoxin, generating a ΔH‡ (koff ) of -10.4 ± 4.3 kJ/mol, suggesting a complex dissociation mechanism. Based on a simple and inexpensive methodology, we determined the values of kon , koff , and Ki of the CTS and provided original kinetics and thermodynamics differences between CTS that could help the design of new compounds. SIGNIFICANCE STATEMENT: This study describes a fast, simple, and cost-effective method for the measurement of phosphatase pNPPase activity enabling structure-kinetics relationships of Na+/K+-ATPase inhibitors, which are important compounds due to their antitumor effect and endogenous role. Using 15 compounds, some of them original, this study was able to delineate the kinetics and/or thermodynamics differences due to the type of sugar and lactone ring present in the steroid structure.

Simple calibration of fisheye lenses for hemispherical photography of the forest canopy

Canopy hemispherical photography (HP) is a technology for vegetation surveying that usually employs consumer-oriented devices. Variations on those devices are caused by technological advances and design. These variations, despite providing the potential for more reliable surveying, make the measurements challenging. The knowledge about how to standardize devices output is available, what is missing is a simple and inexpensive methodology to accomplish it. This is needed since the use of consumer-oriented devices creates an expectation of simplicity and affordability. To fill this methodology gap, we developed an easy-to-assemble calibration board of near-zero material cost (simple board) and outlined how to use it to develop device-specific functions: the projection function (fp) and the vignetting function (fv). The former relates view zenith angle (θ) with distance from image center, while fv models the radial decreasing of brightness known as vignetting effect. Explanations are accompanied by tailored R code. Altogether, we call it “the simple method”. Three devices were used to test it: a Nikon Coolpix 5700 with a FC-E9 converter (D1), a Nikon D610 with a Nikkor 8 mm fisheye lens (D2), and an iPhone 6 Plus with an Olloclip fisheye converter (D3). The reference data was taken with D1, corrected for vignetting effect with a photometric sphere and reprojected to the standard equidistant projection with a fv developed by Delta-T Devices (www.delta-t.co.uk). The root mean square error (RMSE) of the simple method were 0.55° θ and 0.021 relative radiance (RR) for D1; 1.8° θ and 0.1 RR for D2; and 2.1° θ and 0.066 RR for D3. This level of standardization will help to simplify the classification of canopy gaps, a key processing step in HP. And, if it is broadly adopted, will facilitate comparisons between independent studies and large time series.

Detecting Global Events with Bayesian Changepoint Detection on Flight Data

As a means of enhancing the intelligence community’s ability to be prepared and prompt in the detection of global events, we present a Bayesian changepoint detection methodology to detect anomalous activity in open-source flight data. We demonstrate a computationally inexpensive methodology to monitor a geographic location for changes in flight activity over time and demonstrate its utility in a case study of the 2022 Russian invasion of Ukraine. Beyond flight data, the methodology described in this paper shows the potential to generate near real-time situational awareness using open-source time series data streams. This paper was previously published and presented in the Donald R. Keith Memorial Capstone Conference at USMA in May of 2023.

Play in the reading room: Utilizing soft modeling compound to teach musculoskeletal anatomy and pathology.

Musculoskeletal (MSK) anatomy and pathology from a radiology perspective can be difficult to conceptualize and understand due to the challenge of visualizing 3D structures in stacks of 2D imaging. Consequently, trainees may benefit from inexpensive methods that can help trainees better visualize MSK anatomy and pathology. The purpose of this study is to provide proof of concept for inexpensive methodology to help learners such as radiology residents quickly and inexpensively understand musculoskeletal anatomy and pathology. This can help trainees become better at applying musculoskeletal knowledge to clinical practice. Soft-modeling compounds such as Play-Doh® was utilized in a variety of colors with pottery tools to recreate 3D models of challenging MSK anatomy and pathology for trainees. Qualitative feedback from the residents was collected. Eighteen different pathological conditions across six major bone structures were modeled with a soft modeling compound. Residents qualitatively identified the experience as educational in terms of helping them better understand MSK pathology and positive in terms of making learning fun, less stressful, and memorable due to uniqueness of the learning modality. Residents report challenges modeling complex anatomical features and pathology via this methodology. Radiology residents and other learners can enhance their knowledge of musculoskeletal anatomy and pathology via utilization of inexpensive soft modeling compounds. This may offer a cheaper and more time sensitive alternative to current 3-dimensional hardware and software technologies being developed for educational purposes. Additional work needs to be done to examine the utility of this methodology across larger and diverse groups of learners.

THE EFFECTIVENESS OF LEAN SIX SIGMA IMPLEMENTATION IN HEALTH-CARE FACILITIES

This study was conducted to investigate the effectiveness of implementing Lean Six Sigma within the field of health care facilities. Lean Six Sigma is a powerful tool that can increase the organization performance. In this study A systematic review was performed in accordance with current best practices through close adherence to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. This study was found that the implementation of Lean Six Sigma enables the hospital to reduce the consumption of plasminogen by 69%, block utilization was increase by 13%-28%, book appointment increases by 24-276%, time saving were increase by 17% to 21%. And for service quality in blood collection was increased by 55% housewide. Lean Six Sigma is an inexpensive methodology to implement, it can bring many benefits to the organization in the health-care facilities. The successful implementation of Lean Six Sigma was able to reduce waste, reduce defect rate, increasing the quality of service, and reduce process variability that led to patient satisfaction and cost effective.
 Keywords: lean six sigma, health-care facility, productivity, efficiency

Rapid and Simple Buffer Exchange Using Cation-Exchange Chromatography to Improve Point-of-Care Detection of Pharmacological Agents.

The current COVID-19 pandemic has highlighted the power, speed, and simplicity of point-of-care (POC) diagnostics. POC diagnostics are available for a wide range of targets, including both drugs of abuse as well as performance-enhancing drugs. For pharmacological monitoring, minimally invasive fluids such as urine and saliva are commonly sampled. However, false positives or negatives caused by interfering agents excreted in these matrices may confound results. For example, false positives have, in most cases, prevented the use of POC diagnostics for pharmacological agent detection; the consequence is that centralized labs are instead tasked to perform these screenings, resulting in significant delays between sampling and testing. Thus, a rapid, simple, and inexpensive methodology for sample purification is required for the POC to reach a field-deployable tool for the pharmacological human health and performance assessments. Buffer exchange is a simple, rapid approach to remove interfering agents, but has traditionally been difficult to perform on small pharmacological molecules. Therefore, in this communication, we use salbutamol, a performance-enhancing drug, as a case example to demonstrate the efficacy of ion-exchange chromatography as a technique to perform buffer exchange for charged pharmacological agents. This manuscript demonstrates the efficacy of this technique leveraging a commercial spin column to remove interfering agents found in simulant urines, such as proteins, creatinine, and urea, while retaining salbutamol. The utility and efficacy of the method was then confirmed in actual saliva samples. The eluent was then collected and run on the lateral flow assays (LFAs), improving the reported limit of detection by over 5× (new lower limit of detection of 10 ppb compared to reported 60 ppb by the manufacturer) while simultaneously removing noise due to background interfering agents.

Use of caller ID and text messaging from cell phones to increase response rates in patient surveys

Background: High response rates for patient surveys are required in medical literature to ensure non-response bias is minimised. It is often difficult to achieve a satisfactory response rate as patient engagement in surveys is decreasing. A major barrier to phone surveys is getting patients to answer calls from unknown numbers. Purpose: To design a methodology which boosts response rates for telephone-based patient surveys. Research Design: We prospectively analysed the effectiveness of our methodology for increasing patient participation using caller ID and text messanging. Study Sample: Two waves totalling 1313 patients were contacted for participation in a patient survey for a descriptive quantitative and qualitative cohort study using our developed methadology. Data Analysis: We analysed the timepoints at which successful contact was made when using caller ID and text messanging. Results: We achieved a call answer rate of 85.4%, which was a 70.8% increase when compared to a similar patient cohort contacted via blocked caller ID (i.e. with privacy settings). Conclusion: We have developed a simple, inexpensive methodology which, when tested outside the Australian setting and for other projects, shows promise for increasing patient survey response rate.

Democratization of Copper Analysis in Grape Must Following a Polymer-Based Lab-on-a-Chip Approach

Quality control in the food industry is of the upmost importance from the food safety, organoleptic and commercial viewpoints. Accordingly, the development of in situ, rapid, and costless analytical tools is a valuable task in which we are working. Regarding this point, the copper content of grape must has to be determined by wineries along the wine production process. For this purpose, grape must samples are sent to laboratories where the copper content is measured usually by flame atomic absorption spectrometry or by inductively coupled plasma mass spectrometry. We herein propose a straightforward, rapid, and inexpensive methodology based both on a film-shaped colorimetric polymer sensor and a smartphone method that at the same time can be used by unskilled personnel. The sensory polymer films change their color upon dipping them on the grape must, and the color evolution is analyzed using the digital color parameters of a picture taken to the film with a smartphone. Furthermore, the analytical procedure is automatically carried out by a smartphone app. The limit of detection of copper of the polymer sensor is 0.08 ppm. Following this approach, 18 production samples coming from the French Groupe ICV company were studied. The copper content of the samples was analyzed by the usual procedure carried out by the company (flame atomic absorption spectrometry) and by the method proposed in this work, ranging this content from 0.41 to 6.08 ppm. The statistical study showed that the results of both methods are fully consistent, showing the validity of the proposed method for the determination of copper in grape must within the frame of wine production wineries and industries.

Abstract P6-04-02: Ki67 Assessment Protocol: Companion Diagnostic Biomarker for LUMINA Prospective Cohort Study

Abstract Introduction: Luminal A breast cancer is associated with low proliferation, indolent disease biology and limited benefit from chemotherapy. The LUMINA prospective study recently demonstrated a very low 5 year local recurrence rate (2.3%) in women ≥55 years with grade I-II, T1N0 luminal A breast cancer (defined as ER ≥ 1%, PR>20%, HER2 negative and Ki67 index ≤ 13.25%) treated with breast conservation surgery and endocrine therapy without radiation, supporting the safe omission of radiation in this molecularly defined low risk group. Here, we report the protocol for multicentre Ki67 scoring, the embedded integral companion diagnostic employed in LUMINA. Methodology: Ki67 immunohistochemistry was performed on full-face sections at one of the 3 labs and scored by pathologists using an adaptation of the International Ki67 Working Group (IKWG) method. Prior to the start of the study, quality assurance and quality control programs were set up to standardize staining and scoring protocols. All pathologists completed the IKWG training and calibration exercise using a tissue microarray-based series of 18 breast cancers. Inter-laboratory variability was assessed annually during the study period on a set of 9 breast cancer cases with a range of Ki67 scores that purposely over-represented the 13.25% threshold. Stained slides were scanned and images annotated to demarcate invasive carcinoma. Next, 5 random, non-overlapping, 1 mm virtual cores were generated via software and 100 nuclei assessed per core using a keyboard-based counting aid. Ki67 index was derived as the percentage of all counted tumor nuclei that are positively stained. For cases with high Ki67 heterogeneity, additional virtual cores were generated and scored and a 95% confidence interval (CI) of Ki67 index was estimated. The goal was to confidently assign a case as luminal A (≤13.25%) or B (> 13.5%). If the 95% CI crossed 13.25% a recount was performed by an additional pathologist. Results: Quality Assurance Programs: Mean Ki67 index across all cases, labs and years was 13% with high concordance across specimens and score ranges. Observed intra-class correlation coefficients (ICC) were ≥ 0.9, showing near perfect agreement in quantitative Ki67 evaluation. About the 13.25% cutpoint, the observed Kappa statistics were ≥ 0.7 indicating excellent agreement for assignment of luminal A vs. B status. A sub-study was conducted to compare the method of randomly selected virtual fields with the IKWG ‘global weighted score’ method for visual assessment of full-face sections. For this purpose, the 9 quality control cases were reassessed by the same pathologist using the updated IKWG method. Results showed an ICC of 0.96 (0.95% CI: 0.91-0.98) indicating that the Ki67 score generated by the methodology employed in LUMINA trial is highly concordant with the IKWG scoring methodology validated for use on full face sections. Ki67 index summary statistics across LUMINA: Of the 724 eligible cases, 69% (n=500) were assigned as luminal A (median Ki67=7.5%; IQR 5.2-9.8%) and 31% (n=224) as luminal B (median Ki67=19%; IQR 17-23%). Median pathologist scoring time was 4 minutes/case; 45% of cases required scoring of > 5 virtual cores. Per protocol, 39% cases where the initial CI crossed 13.25% were rescored by additional pathologist for final luminal A consensus assignment. Conclusions: Ki67 is a practical biomarker for identifying molecularly defined low-risk luminal A cancers. Our structured quality assurance approach for the trial led to excellent reproducibility and concordance among decentralized labs, supporting applicability of a distributed, inexpensive methodology beyond clinical trial settings and in resource restricted environments. Citation Format: Torsten Nielson, Samuel Leung, Nazia Riaz, Zuzana Kos, Anita Bane, Timothy J. Whelan. Ki67 Assessment Protocol: Companion Diagnostic Biomarker for LUMINA Prospective Cohort Study [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P6-04-02.

Efficient capture of recombinant SARS-CoV-2 receptor-binding domain (RBD) with citrate-coated magnetic iron oxide nanoparticles.

Several vaccines against COVID-19 use a recombinant SARS-CoV-2 receptor-binding domain (RBD) as antigen, making the purification of this protein a key step in their production. In this work, citrate-coated magnetic iron oxide nanoparticles were evaluated as nano adsorbents in the first step (capture) of the purification of recombinant RBD. The nanoparticles were isolated through coprecipitation and subsequently coated with sodium citrate. The citrate-coated nanoparticles exhibited a diameter of 10 ± 2 nm, a hydrodynamic diameter of 160 ± 3 nm, and contained 1.9 wt% of citrate. The presence of citrate on the nanoparticles' surface was confirmed through FT-IR spectra and thermogravimetric analysis. The crystallite size (10.1 nm) and the lattice parameter (8.3646 Å) were determined by X-ray diffraction. In parallel, RBD-containing supernatant extracted from cell culture was exchanged through ultrafiltration and diafiltration into the adsorption buffer. The magnetic capture was then optimized using different concentrations of nanoparticles in the purified supernatant, and we found 40 mg mL-1 to be optimal. The ideal amount of nanoparticles was assessed by varying the RBD concentration in the supernatant (between 0.113 mg mL-1 and 0.98 mg mL-1), which resulted in good capture yields (between 83 ± 5% and 94 ± 4%). The improvement of RBD purity after desorption was demonstrated by SDS-PAGE and RP-HPLC. Furthermore, the magnetic capture was scaled up 100 times, and the desorption was subjected to chromatographic purifications. The obtained products recognized anti-RBD antibodies and bound the ACE2 receptor, proving their functionality after the developed procedure.

Electrodeposition of PEDOT:ClO4 on non-noble tungsten microwire for nerve and brain recordings

A novel simple and inexpensive methodology based on electrodeposition of PEDOT is presented to improve the properties of tungsten microwires, making them a safe and accessible tool in electrophysiology studies.

Comparison of the genetic characteristics of directly measured and Fourier-transform mid-infrared-predicted bovine milk fatty acids and proteins.

Fourier-transform mid-infrared (FT-MIR) spectroscopy is a high-throughput and inexpensive methodology used to evaluate concentrations of fat and protein in dairy cattle milk samples. The objective of this study was to compare the genetic characteristics of FT-MIR predicted fatty acids and individual milk proteins with those that had been measured directly using gas and liquid chromatography methods. The data used in this study was based on 2,005 milk samples collected from 706 Holstein-Friesian × Jersey animals that were managed in a seasonal, pasture-based dairy system, with milk samples collected across 2 consecutive seasons. Concentrations of fatty acids and protein fractions in milk samples were directly determined by gas chromatography and high-performance liquid chromatography, respectively. Models to predict each directly measured trait based on FT-MIR spectra were developed using partial least squares regression, with spectra from a random selection of half the cows used to train the models, and predictions for the remaining cows used as validation. Variance parameters for each trait and genetic correlations for each pair of measured/predicted traits were estimated from pedigree-based bivariate models using REML procedures. A genome-wide association study was undertaken using imputed whole-genome sequence, and quantitative trait loci (QTL) from directly measured traits were compared with QTL from the corresponding FT-MIR predicted traits. Cross-validation prediction accuracies based on partial least squares for individual and grouped fatty acids ranged from 0.18 to 0.65. Trait prediction accuracies in cross-validation for protein fractions were 0.53, 0.19, and 0.48 for α-casein, β-casein, and κ-casein, 0.31 for α-lactalbumin, 0.68 for β-lactoglobulin, and 0.36 for lactoferrin. Heritability estimates for directly measured traits ranged from 0.07 to 0.55 for fatty acids; and from 0.14 to 0.63 for individual milk proteins. For FT-MIR predicted traits, heritability estimates were mostly higher than for the corresponding measured traits, ranging from 0.14 to 0.46 for fatty acids, and from 0.30 to 0.70 for individual proteins. Genetic correlations between directly measured and FT-MIR predicted protein fractions were consistently above 0.75, with the exceptions of C18:0 and C18:3 cis-3, which had genetic correlations of 0.72 and 0.74, respectively. The GWAS identified trait QTL for fatty acids with likely candidates in the DGAT1, CCDC57, SCD, and GPAT4 genes. Notably, QTL for SCD were largely absent in the FT-MIR predicted traits, and QTL for GPAT4 were absent in directly measured traits. Similarly, for directly measured individual proteins, we identified QTL with likely candidates in the CSN1S1, CSN3, PAEP, and LTF genes, but the QTL for CSN3 and LTF were absent in the FT-MIR predicted traits. Our study indicates that genetic correlations between directly measured and FT-MIR predicted fatty acid and protein fractions are typically high, but that phenotypic variation in these traits may be underpinned by differing genetic architecture.

Spatial distribution of particulate matter on winter nights in Temuco, Chile: Studying the impact of residential wood-burning using mobile monitoring

Temuco, a medium-sized city in the south of Chile, is heavily impacted by residential wood-burning particularly in winter, which causes strong episodes of air pollution. We spatially characterized the distribution of particulate matter (PM) during winter nights in Temuco using mobile measurements. In winter 2016 (June 8-July 15th), continuous monitors for PM ≤ 2.5 μm (PM2.5) and ultrafine particles <0.1 μm (UFP) were deployed in a vehicle along with a positioning system during 20 nights (20:00 to 2:00) in assigned routes that crossed the city and additional sampling was conducted at a central site. Measurements were expressed as concentrations and ratios to central site concentrations and collapsed by spatial grids of 50, 100, 200, and 400 m. Average PM2.5 concentrations were ∼100 μg m−3, while UFP ∼30,000 counts cm−3. Some neighborhoods had concentrations of PM2.5 nearly double those measured at a centrally located site, while other neighborhoods had less than half the measured level. We identified hotspots and cold spots of PM2.5 and UFP throughout the urban area—and observed some neighborhoods in which over 20% of the area was categorized as a hotspot for one of the pollutants (14 for PM2.5 and 11 for UFP out of 34). Using mobile monitoring—a relatively simple and inexpensive methodology— we characterized the spatial distribution of pollutants and likely clusters for the time period, which may guide future spatial campaigns and help targeting local interventions aimed at air pollution mitigation.

AUTOMATED ADAPTIVE LIGHT CONTROL FOR AUTOMOBILES

The purpose of this paper is to discuss the design and operation of self-adaptive lights systems in automobiles. The primary goal of this approach is to present an inexpensive methodology for illuminating blind spots and to make the objects visible in dark while driving and during periods of significant diminished visibility in dark locations, thereby avoiding accidents. The reasons for most road accidents without the control of a driver would be due to high beam lights approaching from the vehicles in the opposite direction and the fog causing invisibility of road depending on weather condition and since the beams are focused in a particular direction, it would be difficult in curves to handle the worst situations in driving. To address this problem, motorized headlights that turn according to the steering wheel of a car with adjustable brightness, and depending on atmospheric moisture, fog light is controlled and automatic dim and dip option is used on the basis of opposite vehicle's beam are being proposed as a solution.

Using citizen science to study a mesocarnivore: the jungle catFelis chausin Sri Lanka

AbstractWe used citizen science and inexpensive methodology to assess the distribution of the jungle catFelis chaus, a relatively common species in Sri Lanka but the least studied of the four wild cat species occurring in the country. We obtained three types of records of the jungle cat: geo-referenced photographs of the species from the public; sightings obtained from print and social media, and provided via an online sighting form; and sightings by field biologists. We combined the 112 unique records obtained in this way with the 21 records from the 2012 National Red List distribution map of the species, and usedMaxEntto predict habitat suitability for the species. The new sightings were primarily in drier regions, expanding the known extent of occurrence for this species in Sri Lanka. Of the new sightings, 7.1% were road kills. Distance to nearest riverine forest, annual precipitation and distance to the nearest reservoir were the most important variables explaining habitat suitability. These findings validate our hypotheses that the species is more widespread than demonstrated previously and also ranges in human-dominated landscapes outside protected areas. Our study provides a model for how ecological and behavioural information for common species can be obtained inexpensively and incorporated into species distribution models. Studies of species such as the jungle cat, which are neither threatened nor charismatic, will help ensure that we keep common species common.

Cervical Cancer Diagnostics Healthcare System Using Hybrid Object Detection Adversarial Networks.

Cervical cancer is one of the common cancers among women and it causes significant mortality in many developing countries. Diagnosis of cervical lesions is done using pap smear test or visual inspection using acetic acid (staining). Digital colposcopy, an inexpensive methodology, provides painless and efficient screening results. Therefore, automating cervical cancer screening using colposcopy images will be highly useful in saving many lives. Nowadays, many automation techniques using computer vision and machine learning in cervical screening gained attention, paving the way for diagnosing cervical cancer. However, most of the methods rely entirely on the annotation of cervical spotting and segmentation. This paper aims to introduce the Faster Small-Object Detection Neural Networks (FSOD-GAN) to address the cervical screening and diagnosis of cervical cancer and the type of cancer using digital colposcopy images. The proposed approach automatically detects the cervical spot using Faster Region-Based Convolutional Neural Network (FR-CNN) and performs the hierarchical multiclass classification of three types of cervical cancer lesions. Experimentation was done with colposcopy data collected from available open sources consisting of 1,993 patients with three cervical categories, and the proposed approach shows 99% accuracy in diagnosing the stages of cervical cancer.

A low-effort and inexpensive methodology to determine beam separation distance of multi-foci FLDI

A new method is presented to measure the separation distance between probing volumes of closely spaced multi-foci Focused Laser Differential Interferometers (FLDI). The accuracy and precision of this distance measurement directly translate into the quality of convection velocity measurements performed by means of arrays of FLDI. The suggested method is based on the detection of a propagating weak blast wave, generated with a simple and inexpensive apparatus using an automotive spark plug. Demonstration is conducted using an FLDI with two foci (D-FLDI). The generated blast wave is probed at multiple distances from its source to verify its weakening into an acoustic pulse, which offers ideal conditions to the proposed methodology. D-FLDI separation distance measurement using the new approach is compared to measurements using beam profiler images and to the alternative currently established in the literature, based on the FLDI response to a moving weak lens. Tests are made on varying internal configurations of the D-FLDI, while the distance between the two systems is kept constant. Results show the present method to have improved accuracy and robustness in comparison with the moving lens approach, while requiring significantly less effort. Measured separation distances obtained from blast wave detections in a single location are within 0.5 % of the reference value measured through the beam profiler. This procedure is therefore a practical and reliable alternative to the measurement using beam profiler imaging, with similar quality. Its advantages concern associated costs, flexibility when measuring in constrained spaces such as in proximity to walls, and applicability to systems in which beam imaging is not an option, such as multi-point line FLDI.

Detection of huanglongbing of citruses (Citrus sp.) through Sentinel-2satellite images in Huimanguillo, Tabasco, Mexico

Objective: Develop a fast, practical, and inexpensive methodology for determining plants with HLB symptoms by exploring the potential use of Sentinel-2 satellite images. Design/Methodology/Approach: Sentinel-2 images were used to perform a supervised classification to discriminate healthy Persian lime trees and trees with HLB molecularly verified by qPCR, and other land uses in the citrus growing area of Huimanguillo, Tabasco. Results: The results showed that in the green (560nm), red (665 nm), and near-infrared (705 nm) band regions, the spectral response of trees with HLB is higher than that of healthy trees. Likewise, there is an area of 26.96 and 12 981 hectares of Persian lime affected and free of HLB, respectively, with an accuracy of 0.84 % and a Kappa coefficient of 0.83. Field verification corroborated three plantations where plants with HLB were previously detected and are currently in production. Study Limitations/Implications: The study was carried out in the season of less cloud cover, as this is a limiting factor for the image analysis since it can lead to inadequate tracking of the affected area. Findings/Conclusions: The results showed that it is possible to differentiate Persian lime plants affected by HLB from healthy plants using Sentinel-2 satellite images

Tween 80 Improves the Acid-Fast Bacilli Quantification in the Magnetic Nanoparticle-Based Colorimetric Biosensing Assay (NCBA).

Despite its reduced sensitivity, sputum smear microscopy (SSM) remains the main diagnostic test for detecting tuberculosis in many parts of the world. A new diagnostic technique, the magnetic nanoparticle-based colorimetric biosensing assay (NCBA) was optimized by evaluating different concentrations of glycan-functionalized magnetic nanoparticles (GMNP) and Tween 80 to improve the acid-fast bacilli (AFB) count. Comparative analysis was performed on 225 sputum smears: 30 with SSM, 107 with NCBA at different GMNP concentrations, and 88 with NCBA-Tween 80 at various concentrations and incubation times. AFB quantification was performed by adding the total number of AFB in all fields per smear and classified according to standard guidelines (scanty, 1+, 2+ and 3+). Smears by NCBA with low GMNP concentrations (≤1.5 mg/mL) showed higher AFB quantification compared to SSM. Cell enrichment of sputum samples by combining NCBA-GMNP, incubated with Tween 80 (5%) for three minutes, improved capture efficiency and increased AFB detection up to 445% over SSM. NCBA with Tween 80 offers the opportunity to improve TB diagnostics, mainly in paucibacillary cases. As this method provides biosafety with a simple and inexpensive methodology that obtains results in a short time, it might be considered as a point-of-care TB diagnostic method in regions where resources are limited.

Speciation and Antibiotic Susceptibility Pattern of Coagulase Negative Staphylococci in a Tertiary Care Hospital of Manipur, India

Introduction: Coagulase Negative Staphylococci (CoNS) are common opportunistic pathogens. They are increasingly being recognised as nosocomial pathogens and are associated with multiple antimicrobial resistance mechanisms particularly methicillin resistance. Therefore, rapid and reliable identification upto the species level is necessary to predict the potential pathogenicity or antibiotic susceptibility of each clinical isolate. Aim: Isolation and speciation of CoNS from various clinical samples, and to determine their antibiotic susceptibility pattern. Materials and Methods: This study was a hospital-based crosssectional study carried out in the Department of Microbiology, Jawaharlal Nehru Institute of Medical Sciences (JNIMS), Imphal, Manipur, India, during the period from September 2017- August 2019. CoNS isolates were identified using conventional microbiological procedures and speciation was done following the scheme of Kloos and Schleifer. Antibiotic susceptibility was determined by using the Kirby Bauer’s disk diffusion method. Detection of methicillin resistance among CoNS was performed using cefoxitin disk (30 µg) diffusion method. Data analysis was done using descriptive statistics. Results: CoNS isolates were identified from different clinical specimens, which included 88 (65.2%) from urine, 37 (27.5%) from blood, 3 (2.2%) from pus, 2 (1.5%) from catheter tip, 2 (1.5%) from wound swab, 1 (0.7%) each from aural swab, sputum and ascitic fluid. Predominant isolates were Staphylococcus epidermidis (40.7%) followed by Staphylococcus haemolyticus (19.3%), Staphylococcus hominis (11.9%), Staphylococcus xylosus (7.4%), Staphylococcus saprophyticus (6.0%), Staphylococcus schleiferi (5.2%), Staphylococcus simulans (4.4%), Staphylococcus warneri (3.0%), Staphylococcus lugdunensis (0.7%), Staphylococcus capitis (0.7%) and Staphylococcus cohnii (0.7%). Most isolates were resistant to penicillin (84.5%) and erythromycin (59.3%), and least to tigecycline (2.2%). No resistance to vancomycin and linezolid was seen. Methicillin sensitive CoNS (MSCoNS) was detected in 79 (58.5%) isolates and methicillin resistant CoNS (MRCoNS) in 56 (41.5%) isolates. Conclusion: This study demonstrated the occurrence of various species of CoNS in our healthcare set up with varying antimicrobial susceptibility pattern. Therefore, there is a need for accurate identification to species level by simple, inexpensive methodology and their antibiogram.