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Seismic events disrupt the operation of water distribution networks. Proactive seismic rehabilitation decision-making methods are necessary to ensure maximum serviceability after a seismic event. Most recent proactive seismic rehabilitation decision-making models of water distribution networks are sensitive to network hydraulics and pipe fragilities. Although network hydraulics and pipe fragilities are influenced by pipe degradations, the effects of degradation on proactive seismic rehabilitation decision-making have not been studied. The probabilistic nature of the water pipe degradation makes the consideration of degradation challenging. This research aims to investigate the effects of the degradation of pipes on the seismic rehabilitation decision-making of water distribution networks. The methodology includes (1) designing simulation experiments; (2) integrating the effects of inside and outside degradation with seismic rehabilitation decision-making; and (3) conducting statistical analysis to identify the effects of integrating pipe degradation. The simulation experiments were designed to investigate the effects of degradation on the inside surface of pipes and the outside surface of pipes individually and combinedly. A simulated annealing (SA)–based optimization algorithm was used to identify the critical pipes and associated maximum serviceability for each experiment and each budget constraint. To assess the statistical significance of integrating degradation, two statistical tests were performed. The application of the proposed approach was illustrated on a benchmark network. The selected benchmark network consisted of cast iron pipe and ductile iron pipe. Degradation of cast iron pipe was considered in this study. This framework can be used for other materials. This study was based on five rehabilitation constraints with a focus on rehabilitation costs. The optimization algorithm was employed to identify critical pipes corresponding to each rehabilitation constraint. The results for each simulation experiment showed that the identified critical pipes differed. The associated maximum serviceability was reduced for the same budget constraints if outside and inside degradation were considered individually and combinedly. The associated maximum serviceability was reduced by 3%–4% because of the individual effect of outside or inside degradation, and 6%–7% because of the combined effect of inside and outside degradation. The changes in the identified critical pipes and associated maximum serviceability due to the consideration of outside and inside degradation imply the dependency of a proactive seismic rehabilitation decision-making model on outside and inside degradation. The statistical test results imply that the degradation of pipes in the water distribution network has an impact on seismic rehabilitation decision-making models of water distribution networks. Therefore, it is recommended to integrate the degradation effect with existing seismic rehabilitation decision-making models. [ABSTRACT FROM AUTHOR]

High-frequency speech information is susceptible to inaccurate perception in even mild to moderate forms of hearing loss. Some hearing aids employ frequency-lowering methods such as nonlinear frequency compression (NFC) to help hearing-impaired individuals access high-frequency speech information in more accessible lower-frequency regions. As such techniques cause significant spectral distortion, tests such as the S-Sh Confusion Test help optimize NFC settings to provide high-frequency audibility with the least distortion. Such tests have been traditionally based on speech contrasts pertinent to English. Here, the effects of NFC processing on fricative perception between English and Mandarin listeners are assessed. Small but significant differences in fricative discrimination were observed between the groups. The study demonstrates possible need for language-specific clinical fitting procedures for NFC. [ABSTRACT FROM AUTHOR]

The Handbook of the Sharing Economy, edited by Russell W. Belk, Giana M. Eckhardt, and Fluera Bardhi, provides a comprehensive overview of the sharing economy phenomenon. The book consists of twenty-nine essays written by academics and practitioners from around the world, covering various aspects of the sharing economy. It explores topics such as the nature of sharing, ownership and access, exchange practices, legal and regulatory issues, trust and reputation, and critical perspectives. The book offers valuable insights into the complex and multi-dimensional nature of the sharing economy and suggests areas for future research. It is recommended for both academics and practitioners interested in this emerging field. [Extracted from the article]

The sky is the limit with regards to the societal impact nanomaterials can have on the lives. However, in this study, it is shown that their potential is out of this world. The planet Mars has an abundant source of calcium sulfate minerals and in this work, it is shown that these deposits can be the basis of transformative nanomaterials to potentially support future space endeavors. Vitally, the methods applied are low cost and require no specialized instruments of great expertise, strengthening the potential involvement of nanotechnology in sustaining Martian inhabitation. Through a scalable eco‐friendly liquid processing technique performed on two common terrestrial gypsum, this simple method presented a cost‐efficient procedure to yield suspensions of large aspect ratio anhydrite nanobelts with long‐term stability that are characterized through scanning electron microscopy and Raman spectroscopy. Transmission electron microscopy shows nanobelts to have a mesocrystal structure, with distinct nanoparticle constituents making up the lattice. Unexpectedly, anhydrite nanobelts have remarkable electronic properties, namely a bandgap that is easily tuned between semiconducting (≈2.2 eV) and insulating (≈4 eV) behaviors through dimensional control measured via atomic force microscopy. To demonstrate the application potential of the nanobelts; optoelectronic, electrochemical, and nanocomposite measurements are made. [ABSTRACT FROM AUTHOR]

Whereas much research has looked at how recommendation systems influence online purchase intentions, this article illustrates the dual process model by which they occur. Using two studies, we fill the research void in interactive marketing by demonstrating how the dual processes of social proof and risk avoidance mediate the impact of recommendation labels on consumer decision-making contingent upon their level of involvement. Study 1 (n = 73), used a mixed-subjects design with a college student sample to demonstrate that both types of recommendation labels will lead to higher purchase intentions in an online setting. Most importantly, it provides evidence for the main effect of our theoretical model across different product categories. Study 2 (n = 160) provides support for our remaining four hypotheses by demonstrating the underlying process through which recommendation labels have a two-fold effect on purchase intentions. Specifically, the recommendation label increased the risk avoidance effect for high-involvement consumers and enhanced the social proof effect for low-involvement consumers. In both cases, the recommendation labels increased purchase intentions. Implications of our findings for theoretical and practical contributions and future directions are also explored. [ABSTRACT FROM AUTHOR]

This article calls for enhancing the horizon of Political Communication Studies, drawing attention to certain relation between the media, the state and the public in a globalised world. Focusing on private mainstream news television in post-liberalisation India, it tries to show how Media, in its singularised popular sense of sensationalising news, generating live-stream of public opinion, conducting parallel investigation of crimes, judging the sub judice and posing as sovereign by perennially endorsing the logic of self-regulation, tries to appropriate the functions, image and rhetoric of the state institutions (the executive, the judiciary and the legislature). The article primarily explores the quasi-executive functions to understand the role of a seemingly autonomous public in Indian democracy. The increasing tussle that we are witnessing between the executive, the legislature and the judiciary, the article argues, is to a large extent due to Media's claim to represent the public more effectively than any state institution, pushing "pillars of democracy" to fight with each other for their share of credit in serving the public. [ABSTRACT FROM AUTHOR]

Spatiotemporally dynamic microtubule acetylation underlies diverse physiological and pathological events. Despite its ubiquity, the molecular mechanisms that regulate the sole microtubule acetylating agent, α-tubulin-N-acetyltransferase-1 (α-TAT1), remain obscure. Here, we report that dynamic intracellular localization of α-TAT1 along with its catalytic activity determines efficiency of microtubule acetylation. Specifically, we newly identified a conserved signal motif in the intrinsically disordered C-terminus of α-TAT1, consisting of three competing regulatory elements--nuclear export, nuclear import, and cytosolic retention. Their balance is tuned via phosphorylation by CDK1, PKA, and CK2, and dephosphorylation by PP2A. While the unphosphorylated form binds to importins and resides both in cytosol and nucleus, the phosphorylated form binds to specific 14-3-3 adapters and accumulates in the cytosol for maximal substrate access. Unlike other molecules with a similar phospho-regulated signal motif, α-TAT1 uniquely uses the nucleus as a hideout. This allosteric spatial regulation of α-TAT1 function may help uncover a spatiotemporal code of microtubule acetylation in normal and aberrant cell behavior. [ABSTRACT FROM AUTHOR]

This research study aims to measure the Open Access (OA) friendliness of National Institutes of Technology (NITs) of India that are listed in the overall category of NIRF (National Institutional Ranking Framework), 2021 by taking into consideration four important OA parameters – i) OA publication share; ii) OA licensing scenario; iii) citation impact of OA publications; and iv) altmetric scores of OA publications. It deals with 64,485 publications of the selected 11 NITs during the period from 2012 to 2021 (10 years), citations received by these publications (5,42,638 citations), and altmetric attention scores of the documents (5,213 publications) during the period under study. A data carpentry tool, namely OpenRefine, and open access bibliographic/citation data sources such as Unpaywall, Dimensions, and Altmetric.com have been deployed to accomplish this large-scale study for ranking NITs by their Open Access Friendliness (OAF). The OAF indicator, as applied in this study, is a distributed weightage based 100-point scale built on top of the aforesaid OA parameters. The ranking framework shows that Sardar Vallabhbhai National Institute of Technology, Surat (est. in 1961) has achieved the top position with a score of 52.12 (out of 100), but in totality only 3 NITs (out of the selected 11 NITs) crossed the 50 per cent mark in the adapted OAF scale. [ABSTRACT FROM AUTHOR]

The present research aims to investigate the open access (OA) friendliness of the twenty-six (26) state universities that have been ranked in the National Institutional Ranking Framework's (2021) 'Overall Category' (Rank Band 1: Top 100). The open-access ranking framework, as designed, is based on four major OA areas: i) proportion of OA publications by a given state university; ii) use of a license in sharing OA publications; iii) citations received by OA publications; and iv) popularity of OA publications in socio-academic web-space as indicated by altmetric attention scores. Ten years (2012-2021) primary publication data for the 26 state universities from Scopus was collected. We analyzed a total of 1,57,971 publications; 1,60,723 citations received by these publications; and altmetric attention scores received by 26,996 publications from these 26 state universities listed in the NIRF 2021 overall category. It applies an open-source data wrangling tool (OpenRefine) and a number of ODbL-based (Open Database License) data sources to gather the necessary data elements required for this large-scale study. The study finds that almost 98% of the state universities enlisted in the top 100 overall category passed the 50 marks on a 100-point scale, and the newly established state universities' open access friendliness is greater than the older ones. The final open access friendliness ranking places King Georges Medical University at the top, with leading scores in areas I (share of OA publications) and III (OA citation share), while Panjab University has the highest value in Area II (use of license in OA publications) and Delhi Technological University has the highest value in Area IV (OA altmetric attention score). [ABSTRACT FROM AUTHOR]

Past earthquakes have revealed that earthquakes disrupt operations of underground water infrastructure systems. Assessment of the seismic vulnerability of underground water pipe networks plays a critical role in formulating preventive rehabilitation decision making to avoid high repair costs. Although existing seismic vulnerability assessment methods are sensitive to water pipe network uncertainties (e.g., uncertainties in nodal demand, reservoir head, and pipe roughness coefficient), the extent of the effects of these uncertainties on the postearthquake serviceability of the networks has not been examined. This research investigates the effects of water pipe network uncertainties on the seismic vulnerability assessment of networks. Transient ground displacements due to seismic wave propagation are considered for this investigation. The methodology includes seven steps: uncertainty identification and quantification, design of experiments, integrated multiphysics modeling, seismic repair rate calculations, Monte Carlo simulation, statistical analysis of the data (ANOVA and Tukey tests), and sensitivity analysis. Uncertainties in nodal demand, reservoir head, and pipe roughness coefficient were examined in this study. An integrated multiphysics model was created to simulate hydraulic network behavior and seismic vulnerability assessment. The approach was tested on two networks (New York Tunnel Network and Oberlin Network). The statistical analysis results indicated that the combined impact of the three selected water pipe network uncertainties on the seismic vulnerability assessment of networks is statistically significant. Nodal demand and pipe roughness coefficient uncertainties did not individually have a statistically significant effect. The individual effect of reservoir head uncertainty was statistically significant. Sensitivity analysis determined the minimum value of the coefficient of variation to have a statistically significant effect. Sensitivity analysis was divided into three parts to investigate the individual and combined effects of network uncertainties. The results from sensitivity analysis showed that a small uncertainty in reservoir head results in a statistically significant effect on seismic vulnerability assessment. By contrast, the coefficient of variation for uncertainties in nodal demand and pipe roughness has to be quite large to significantly affect seismic vulnerability assessment. Statistical analysis and sensitivity analysis results showed that water pipe network uncertainties have a statistically significant impact on seismic vulnerability assessment of networks. Hence, it is recommended to integrate water pipe network uncertainties with existing methods for assessing seismic vulnerabilities. [ABSTRACT FROM AUTHOR]

Flow stratigraphy has been carried out in the Rajmahal Traps from exploratory boreholes drilled for coal in the western sector of Bengal Basin. Different volcanic flows have been demarcated according to their broad megascopic characters. These flows are primarily basaltic in nature. It mainly contains plagioclase, augite along with magnetite and Ti-magnetite and shows porphyritic texture. Inter-trappean sediments are largely argillaceous in nature and restricted towards the lower part of this volcanic sequence. However, a prominent megacrystic plagioclase bearing basaltic flow zone occurs persistently in the middle part. It demarcates two separate modes of eruption in the entire volcanic sequence. Episodic volcanism during initial phase results intermittent deposition of inter-trappean sediments below this zone whereas eruption becomes fairly continuous during later stage which inhibits sedimentation above the megacrystic flow. As this megacrystic zone is very prominent and well persistent, it can be treated as marker horizon. [ABSTRACT FROM AUTHOR]

The segmentation of breast lesions is an important step in the computer‐aided analysis of the mammogram. The presence of noise in mammograms makes lesion detection challenging particularly for complex malignant lesions. Pre‐processing techniques can deal with the noise issue but distorts the important shape features. This motivates us to propose a novel hybrid approach by combining a convolution neural network (CNN) with connected component analysis (CCA) to segment malignant breast lesions without any pre‐processing to avoid any distortion in image sharpness at the initial stages. Two well‐known segmentation techniques namely, K‐means (KM) and Fuzzy c‐means (FCM) are also used to compare the results. From a pool of 1045 mammographic cancer images acquired from the Digital Database for Screening Mammography (DDSM), 1016 are used for training and validation, and 29 are used for testing. All three results (Hybrid, KM and FCM) are compared against the results by the expert Radiologist. The results indicate that, among various segmentation techniques, the proposed hybrid approach achieves the highest accuracy (90%), Matthew's correlation coefficient (0.79), Jaccard index (0.73) and the Dice similarity coefficient (0.84). Other performance evaluation techniques such as; precision, sensitivity, specificity, false‐positive rate, false discovery rate, negative predictive value and false‐negative rate also show the superior performance of the proposed hybrid approach. Statistical analysis (Mann–Whitney U test, T‐test, Chi‐square test, Kolmogorov–Smirnov test and Wilcoxon test), graphical analysis (Regression and Bland–Altman plots) and receiver operating characteristic curve further demonstrate the stability and consistency of the results. [ABSTRACT FROM AUTHOR]

• Production and entrapment of the CRAND protons at the low Earth orbit. • Event by event simulation procedure using Monte Carlo technique. • Comparison of trapped protons measured by PAMELA and simulated results. • Trapped proton distribuiton in the radiation belt and discussions on the features. The Cosmic Ray Albedo Neutron Decay (CRAND) is believed to be the principal mechanism for the formation of inner proton radiation belt – at least for relatively higher energy particles. We implement this mechanism in a Monte Carlo simulation procedure to calculate the trapped proton radiation at the low Earth orbits, through event-by-event interaction of the cosmic ray particles in the Earth's atmosphere and their transportation in the magnetosphere. We consider the generation of protons from subsequent decay of the secondary neutrons from the cosmic ray interaction in the atmosphere and their transport (and/or trapping) in the geomagnetic field. We address the computational challenges for this type of calculations and develop an optimized algorithm to minimize the computation time. We consider a full 3D description of the Earth's atmospheric and magnetic-field configurations using the latest available models. We present the spatial and phase-space distribution of the trapped protons considering the adiabatic invariants and other parameters at the low Earth orbits. We compare the simulation results with the trapped proton flux measurements made by PAMELA experiment at low Earth orbit and explain certain features observed by the measurement. [ABSTRACT FROM AUTHOR]

This document is a review of the book "Advanced Introduction to the Experience Economy" by Jon Sundbo. The book explores the concept of the experience economy, where businesses focus on creating and selling unique and engaging experiences rather than just goods and services. The author discusses the theoretical underpinnings of the experience economy, its relevance in various sectors such as tourism and culture, and the measurement of experiences within different sectors. The book also addresses the psychological, marketing, production, and digital aspects of the experience economy, as well as its macro factors and potential future developments. The reviewer suggests that a future edition should include a chapter on the metaverse and its impact on the experience economy. Overall, the book provides a comprehensive overview of the concept and its interdisciplinary nature. [Extracted from the article]

We performed a detailed modelling of the background counts observed in a phoswich scintillator X-ray detector at balloon altitude, used for astronomical observations, on board small scientific balloon. We used Monte Carlo simulation technique in Geant4 simulation environment, to estimate the detector background from various plausible sources. High energy particles and radiation generated from the interaction of Galactic Cosmic Rays with the atmospheric nuclei is a major source of background counts (under normal solar condition) for such detectors. However, cosmogenic or induced radioactivity in the detector materials due to the interaction of high energy particles and natural radioactive contamination present in the detector can also contribute substantially to the detector background. We considered detailed 3D modelling of the earth's atmosphere and magnetosphere to calculate the radiation environment at the balloon altitude and deployed a proper mass model of the detector to calculate the background counts in it. The calculation satisfactorily explains the observed background in the detector at 30 km altitude (atmospheric depth: 11.5 g/cm2) during the balloon flight experiment from a location near 14.5 ° N geomagnetic latitude. [ABSTRACT FROM AUTHOR]

The random intensity distribution observed due to the propagation of a coherent beam of light through a scattering medium is known as a speckle pattern. The interaction of speckles with a birefringent crystal, here, YVO4 results in the splitting of the speckles into e-ray and o-ray speckles. It is observed that the e-ray and o-ray speckles experience an angular shift with the rotation of the crystal and the amount of the shift depends on the rotation angle of the crystal. It is also found that the rate of the shift is different for e-ray and o-ray speckles, and is independent of the topological charge of the beam incident on the scattering medium. The observed rate of shift of the speckles is found to be same as that of the e-ray and o-ray beams. It is experimentally demonstrated that the rotation of a birefringent crystal can be tracked very accurately from the speckle correlation. [ABSTRACT FROM AUTHOR]

A technique based on the superposition of two uncorrelated speckle patterns and speckle contrast measurement is proposed and demonstrated to track the polarization rotation of an optical beam behind a scattering layer. One of the superposed speckle patterns is considered as reference, and it is shown that with the help of the reference speckle pattern of a known linear polarization, it is possible to track the polarization rotation behind a scattering layer in a non-invasive manner by measuring the contrast of the resultant speckle pattern. The working principle and the experimental demonstration of the proposed technique are presented, and the experimental results are compared with the theoretically predicted values. The performance of the proposed technique is quantitatively evaluated by determining the rotation of the polarization vector behind the scattering layer for two different cases, namely, polarization rotation by a half-wave plate and sugar solution of different concentrations, and good matches are found between the experimental results and the theoretical prediction. Issues like resolution of tracking the polarization vector rotation and determination of sugar solution concentration are also discussed in the context of the experimental results. The proposed technique can have potential applications in non-invasive sensing and biomedical studies. [ABSTRACT FROM AUTHOR]

Fully Convolutional Neural Networks (F-CNNs) achieve state-of-the-art performance for segmentation tasks in computer vision and medical imaging. Recently, computational blocks termed squeeze and excitation (SE) have been introduced to recalibrate F-CNN feature maps both channel- and spatial-wise, boosting segmentation performance while only minimally increasing the model complexity. So far, the development of SE blocks has focused on 2D architectures. For volumetric medical images, however, 3D F-CNNs are a natural choice. In this article, we extend existing 2D recalibration methods to 3D and propose a generic compress-process-recalibrate pipeline for easy comparison of such blocks. We further introduce Project & Excite (PE) modules, customized for 3D networks. In contrast to existing modules, Project & Excite does not perform global average pooling but compresses feature maps along different spatial dimensions of the tensor separately to retain more spatial information that is subsequently used in the excitation step. We evaluate the modules on two challenging tasks, whole-brain segmentation of MRI scans and whole-body segmentation of CT scans. We demonstrate that PE modules can be easily integrated into 3D F-CNNs, boosting performance up to 0.3 in Dice Score and outperforming 3D extensions of other recalibration blocks, while only marginally increasing the model complexity. Our code is publicly available on https://github.com/ai-med/squeeze_and_excitation. [ABSTRACT FROM AUTHOR]

The study of secondary particles produced by the cosmic-ray interaction in the Earth's atmosphere is very crucial as these particles mainly constitute the background counts produced in the high-energy detectors at balloon and satellite altitudes. In the present work, we calculate the abundance of cosmic-ray generated secondary particles at various heights of the atmosphere by means of a Monte Carlo simulation and use this result to understand the background counts in our X-ray observations using balloon-borne instruments operating near the tropical latitude (geomagnetic latitude: ~ 14.50 ° N). For this purpose, we consider a 3D description of the atmospheric and geomagnetic field configurations surrounding the Earth, as well as the electromagnetic and nuclear interaction processes using Geant4 simulation toolkit. Subsequently, we use a realistic mass model description of the detector under consideration, to simulate the counts produced in the detector due to secondary cosmic-ray particles. [ABSTRACT FROM AUTHOR]

Positioning and repositioning continue to be critical topics in business strategy, and yet a review of current business research syllabi from several institutions showed that very few institutions teach the analytical underpinnings of how perceptual maps can be created using multidimensional scaling and how they should be interpreted. At the outset, the author defines multidimensional scaling and reviews various software packages that are available to create such maps, followed by an overview of a sample assignment. Then the benefits to the students are discussed, followed by extensions in graduate and in online classes as well as the impact and effectiveness of the teaching innovation. [ABSTRACT FROM AUTHOR]

[Display omitted] • CeO 2 nanostructure tailored via hydrothermal synthesis conditions. • Improved activity in plasma-CO 2 methanation for CeO 2 nanoneedle and nanorod supports. • Higher O-exchange and lower dielectric permittivity boost the energy efficiency. • Nanostructure design is a promising way to enhance plasma-catalytic performance. Plasma-assisted CO 2 methanation has been recently presented as a highly promising route towards the electrification of power-to-gas processes, a key step in our transition to sustainable energy generation. Interesting results have been obtained via the combination of cold plasmas – such as Dielectric Barrier Discharge – and Ni-catalysts prepared using CeO 2 -containing oxides as support, well known for they ability towards oxygen exchange. In the present work, the physicochemical and dielectric properties of Ni/CeO 2 catalysts were tailored through the modification of the nanostructured morphology of pure CeO 2 , as an alternative to the use of dopants/promoters. Improved efficiency was observed in the presence of CeO 2 nanoneedles and nanorods exposing 〈0 1 1〉 facets, more prompt to oxygen exchange. The lower dielectric permittivity of these materials led to a more efficient management of adsorbed species during on-plasma operation, resulting in improved plasma-catalytic behavior. [ABSTRACT FROM AUTHOR]

The findings demonstrate that marketers should be aware of other cultural differences across global markets, even if some consumer behavior is consistent across cultures. Handbook on Cross-Cultural Marketing: Edited by Glen H. Brodowsky and Camille P. Schuster. Hewett and Allman in Chapter 9, empirically consider the issue of how consumers with holistic (interdependent) versus analytic (independent) cognitive thinking styles differentially process technology related information of new products in forming brand image evaluations. [Extracted from the article]

We introduce Bayesian QuickNAT for the automated quality control of whole-brain segmentation on MRI T1 scans. Next to the Bayesian fully convolutional neural network, we also present inherent measures of segmentation uncertainty that allow for quality control per brain structure. For estimating model uncertainty, we follow a Bayesian approach, wherein, Monte Carlo (MC) samples from the posterior distribution are generated by keeping the dropout layers active at test time. Entropy over the MC samples provides a voxel-wise model uncertainty map, whereas expectation over the MC predictions provides the final segmentation. Next to voxel-wise uncertainty, we introduce four metrics to quantify structure-wise uncertainty in segmentation for quality control. We report experiments on four out-of-sample datasets comprising of diverse age range, pathology and imaging artifacts. The proposed structure-wise uncertainty metrics are highly correlated with the Dice score estimated with manual annotation and therefore present an inherent measure of segmentation quality. In particular, the intersection over union over all the MC samples is a suitable proxy for the Dice score. In addition to quality control at scan-level, we propose to incorporate the structure-wise uncertainty as a measure of confidence to do reliable group analysis on large data repositories. We envisage that the introduced uncertainty metrics would help assess the fidelity of automated deep learning based segmentation methods for large-scale population studies, as they enable automated quality control and group analyses in processing large data repositories. [ABSTRACT FROM AUTHOR]

In a wide range of semantic segmentation tasks, fully convolutional neural networks (F-CNNs) have been successfully leveraged to achieve the state-of-the-art performance. Architectural innovations of F-CNNs have mainly been on improving spatial encoding or network connectivity to aid gradient flow. In this paper, we aim toward an alternate direction of recalibrating the learned feature maps adaptively, boosting meaningful features while suppressing weak ones. The recalibration is achieved by simple computational blocks that can be easily integrated in F-CNNs architectures. We draw our inspiration from the recently proposed “squeeze and excitation” (SE) modules for channel recalibration for image classification. Toward this end, we introduce three variants of SE modules for segmentation: 1) squeezing spatially and exciting channel wise; 2) squeezing channel wise and exciting spatially; and 3) joint spatial and channel SE. We effectively incorporate the proposed SE blocks in three state-of-the-art F-CNNs and demonstrate a consistent improvement of segmentation accuracy on three challenging benchmark datasets. Importantly, SE blocks only lead to a minimal increase in model complexity of about 1.5%, while the Dice score increases by 4%–9% in the case of U-Net. Hence, we believe that SE blocks can be an integral part of future F-CNN architectures. [ABSTRACT FROM AUTHOR]

Abstract Whole brain segmentation from structural magnetic resonance imaging (MRI) is a prerequisite for most morphological analyses, but is computationally intense and can therefore delay the availability of image markers after scan acquisition. We introduce QuickNAT, a fully convolutional, densely connected neural network that segments a MRI brain scan in 20 s. To enable training of the complex network with millions of learnable parameters using limited annotated data, we propose to first pre-train on auxiliary labels created from existing segmentation software. Subsequently, the pre-trained model is fine-tuned on manual labels to rectify errors in auxiliary labels. With this learning strategy, we are able to use large neuroimaging repositories without manual annotations for training. In an extensive set of evaluations on eight datasets that cover a wide age range, pathology, and different scanners, we demonstrate that QuickNAT achieves superior segmentation accuracy and reliability in comparison to state-of-the-art methods, while being orders of magnitude faster. The speed up facilitates processing of large data repositories and supports translation of imaging biomarkers by making them available within seconds for fast clinical decision making. Graphical abstract Image 1 Highlights • Introduces a deep learning based whole brain segmentation tool called QuickNAT, processing each 3D MRI T1 brain scans in 20 secs. • The high segmentation accuracy of QuickNAT was evaluated on 5 different benchmark datasets, containing a wide age range, subjects with different pathologies (AD, MCI and CN), and different scanners (1.5T and 3.0T). • QuickNAT can be effectively used for longitudinal studies as it performs well in test-retest and multi-center experiments. [ABSTRACT FROM AUTHOR]

An enzyme aggregate of alginate lyase (EC 4.2.2.3) from flavobactierium was prepared using ammonium sulfate. The resultant aggregates upon cross-linking with glutaraldehyde produced insoluble and catalytically active cross-linked enzyme aggregate (CLEA) enzyme. The catalytic activity and stability of the cross-linked enzyme aggregate of alginate lyase (CLEA-AL) was studied in the presence of various pH, temperatures and organic solvents. Reusability, storage stability and surface morphology of the CLEA-AL were also studied. The native enzyme and CLEA-AL exhibited maximum enzyme activity at pH of 6.3 and at a temperature of 40 °C. The CLEA-AL has good stability in nonpolar organic solvents and is thermally stable up to 50 °C over a period of 8 h. By encapsulating CLEA-AL into alginate hydrogel, we demonstrate that alginate hydrogels can be enzymatically degraded in a controlled fashion. The results also showed that degradation of alginate hydrogel with CLEA-AL incorporated beads is slower than native enzyme and therefore, CLEA-AL can be used for controlled degradation and release of various biologics from the degrading gel. [ABSTRACT FROM AUTHOR]

An efficient phenol degrading mixed bacterial culture was isolated from sludge sample collected from one of the refinery located in Assam, India. The mixed culture was found to consist of three bacterial strains. These were identified as Stenotrophomonas acidaminiphila , Brevibacterium sp . and Brucella sp . Batch phenol biodegradation experiments were carried out for a wide range of initial phenol concentrations after pH and temperature optimization. It was found that the mixed culture was able to degrade a maximum phenol concentration up to 1000 mg L −1 within 96 h while the maximum specific growth rate ( μ max ) was observed at 100 mg L −1 . The pH and temperature required for optimal phenol degradation was 6.5 and 37 °C respectively. The mixed culture degrades phenol via ortho -cleavage pathway by formation of an intermediate ( cis , cis- muconate) which was detected spectrophotometrically at 260 nm. The experimental data were validated by fitting the growth and substrate utilization curves with their corresponding simulated dynamic profiles obtained by solving Haldane's equation via MATLAB R2015a with μ max = 0.155 h −1 and K I = 400 mg L −1 . [ABSTRACT FROM AUTHOR]

The major contributions of this work are summarized below. • A new technique is developed to control the spatial coherence-polarization from intensity basis addition of speckle patterns. • The biggest advantage of this technique is the non-requirement of an interferometer for its implementation, unlike field basis addition based approaches. • The spatial coherence-polarization property is found to be dependent also on the sum of the polarization vectors' orientations of the constituent speckle patterns. • Speckles with lower spatial coherence than the original depolarized field can be generated using this technique. A technique based on an intensity basis addition of two speckle patterns with polarization diversity, which are filtered from a depolarized field, is developed to modulate the spatial coherence-polarization (CP) property of the superposed speckle pattern. It is proposed theoretically, and validated both experimentally and numerically that by tuning the polarization diversity of the constituent speckle patterns, a complete control over the spatial coherence of the superposed speckle pattern can be achieved, and the superposed speckles can be modulated from fully spatially coherent to spatially incoherent in a controlled fashion. It is also observed that if the original field is not completely depolarized, the achieved modulation of the spatial coherence not only depends on the mutual orientation of the polarization vectors of the constituent speckle patterns (as in the case of the field basis addition of speckles) but also on the sum of the polarization orientations. However, the achieved modulation is found to be similar to the case of the addition of speckle patterns in the field basis, if the original field is completely depolarized. This work may have potential application in biomedical imaging, where the intensity basis addition of speckle patterns is widely used to reduce the speckle noise. [ABSTRACT FROM AUTHOR]

Nanostructured ceramic particles, particularly, nanoparticles of calcium phosphate (CaP) remain an attractive option among the various types of non-viral gene delivery vectors studied because of their safety, biocompatibility, biodegradability, and ease of handling as well as their adsorptive capacity for DNA. We have accordingly developed an enhanced version of nanostructured calcium phosphates (NanoCaPs), by substituting known amounts of silicate for phosphate in the hydroxyapatite (HA) lattice (NanoSiCaPs). Results indicate that in addition to the excellent transfection levels exhibited by un-substituted NanoCaPs alone in vitro, an additional 20–50% increase in transfection is observed for NanoCaPs containing 8.3–50 mol% silicate aptly called NanoSiCaPs, owing to its rapid dissolution properties enabling nanoparticles escaping the lysosomal degradation. However, high silicate substitution (> 50 mol%) resulted in a drastic decline in transfection as the synthesized NanoCaPs deviated far from the characteristic hydroxyapatite phase formed as evidenced by the materials characterization results. [ABSTRACT FROM AUTHOR]

Propagation of a coherent light through an anisotropic random medium generates randomly polarized field, known as polarization speckle. In this paper, an experimental technique is proposed and demonstrated to recover the transmittance of a polarized object from polarization speckle. Recovery of the polarized object from polarization speckle is made possible by combining the far-field intensity correlation of the object speckle with off-axis holography to determine the complex coherence function of the speckle. The desired object speckle which is uniformly polarized is filtered from the polarization speckle using a polarizer. The results are compared with the case where the complex coherence function is determined in the absence of the polarizer. [ABSTRACT FROM AUTHOR]

Biphasic mixtures of crystalline β-tricalcium magnesium phosphate (β-TCMP) and an amorphous calcium magnesium phosphate have been synthesized and reported to support enhanced hMSC differentiation in comparison to β-tricalcium phosphate (β-TCP) due to the release of increased amounts of bioactive ions. In the current study, completely amorphous β-TCMP has been synthesized which is capable of releasing increased amounts of Mg 2 + and PO 4 3 − ions, rather than a biphasic mixture as earlier reported. The amorphous phase formed was observed to crystallize between temperatures of 400–600 °C. The scaffolds prepared with amorphous β-TCMP were capable of supporting enhanced hMSC proliferation and differentiation in comparison to commercially available β-TCP. However, a similar gene expression of mature osteoblast markers, OCN and COL-1, in comparison to biphasic β-TCMP was observed. To further study the role of Mg 2 + and PO 4 3 − ions in regulating hMSC osteogenic differentiation, the capability of hMSCs to mineralize in growth media supplemented with Mg 2 + and PO 4 3 − ions was studied. Interestingly, 5 mM PO 4 3 − supported mineralization while the addition of 5 mM Mg 2 + to 5 mM PO 4 3 − inhibited mineralization. It was therefore concluded that the release of Ca 2 + ions from β-TCMP scaffolds also plays a role in regulating osteogenic differentiation on these scaffolds and it is noted that further work is required to more accurately determine the exact role of Mg 2 + in regulating hMSC osteogenic differentiation. [ABSTRACT FROM AUTHOR]

Biphasic mixtures of either Mg 2 + or combined Mg 2 + and Sr 2 + cation substituted β-tricalcium phosphate (β-TCP) and amorphous calcium phosphate (ACP) were prepared using a low temperature chemical phosphatizing and hydrolysis reaction approach. Scaffolds prepared using the cation substituted calcium phosphates were capable of supporting similar levels of human mesenchymal stem cell proliferation in comparison to commercially available β-TCP. The concentrations of Mg 2 + , Sr 2 + , and PO 4 3 − released from these scaffolds were also within the ranges desired from previous reports to support both hMSC proliferation and osteogenic differentiation. Interestingly, hMSCs cultured directly on scaffolds prepared with only Mg 2 + substituted β-TCP were capable of supporting statistically significantly increased alkaline phosphatase activity, osteopontin, and osteoprotegerin expression in comparison to all compositions containing both Mg 2 + and Sr 2 + , and commercially available β-TCP. hMSCs cultured in the presence of scaffold extracts also exhibited similar trends in the expression of osteogenic markers as was observed during direct culture. Therefore, it was concluded that the enhanced differentiation observed was due to the release of bioactive ions rather than the surface microstructure. The role of these ions on transforming growth factor-β and bone morphogenic protein signaling was also evaluated using a PCR array. It was concluded that the release of these ions may support enhanced differentiation through SMAD dependent TGF-β and BMP signaling. [ABSTRACT FROM AUTHOR]

Ionic substitutions in hydroxyapatite (HA) scaffolds and self-setting cements containing Sr 2 + ions incorporated are particularly of interest in bone regeneration. To date, the approach widely used to incorporate Sr 2 + ions into HA cements has been the addition of Sr 2 + containing salts, such as SrCO 3 , SrCl 2 ∙ 6H 2 O, or SrHPO 4 . However, this approach is dependent upon the relative solubility of Sr 2 + containing salts with respect to calcium phosphate (CaP) precursors. Therefore, in the current study Sr 2 + substituted dicalcium phosphate dihydrate (DCPD) was first synthesized and directly reacted with tetracalcium phosphate (TTCP) to form Sr 2 + substituted HA forming cements. Rietveld refinement indicated that after one week of aging in phosphate buffered saline, cements prepared with and without Sr 2 + were composed of 75% HA and 25% unreacted TTCP by weight. Cements prepared with 10% Sr 2 + DCPD exhibited increased compressive strengths in comparison to unsubstituted cements. Increased MC3T3-E1 proliferation and differentiation were also observed on the cements prepared with increasing Sr 2 + content. It was concluded that both the scaffold microstructure and Sr 2 + ion release supported osteogenic differentiation. With respect to osteoclastic differentiation, no statistically significant differences in TRAP activity or cell morphology were observed. This suggests that the amount of Sr 2 + released may have been too low to influence osteoclast formation in comparison to unsubstituted cements. The results obtained herein demonstrate that the use of Sr 2 + substituted DCPD precursors rather than individually separate Sr 2 + containing salts may be a useful approach to prepare Sr 2 + containing HA cements. [ABSTRACT FROM AUTHOR]

Calcium phosphate based cements (CPCs) are frequently used as bone void fillers for non-load bearing segmental bone defects due to their clinically relevant handling characteristics and ability to promote natural bone growth. Macroporous CPC scaffolds with interconnected pores are preferred for their ability to degrade faster and enable accelerated bone regeneration. Herein, a composite CPC scaffold is developed using newly developed resorbable calcium phosphate cement (ReCaPP) formulation containing degradable microspheres of bio-compatible poly (lactic-co-glycolic acid) (PLGA) serving as porogen. The present study is aimed at characterizing the effect of in-vitro degradation of PLGA microspheres on the physical, chemical and structural characteristics of the composite cements. The porosity measurements results reveal the formation of highly interconnected macroporous scaffolds after degradation of PLGA microspheres. The in-vitro characterizations also suggest that the degradation by products of PLGA reduces the pH of the local environment thereby increasing the dissolution rate of the cement. In addition, the in-vitro vancomycin release from the composite CPC scaffold suggests that the drug association with the composite scaffolds can be tuned to achieve control release kinetics. Further, the study demonstrates control release lasting for longer than 10 weeks from the composite cements in which vancomycin is encapsulated in PLGA microspheres. [ABSTRACT FROM AUTHOR]

The present study was aimed to investigate phytochemical screening and to evaluate reducing power, cytotoxicity and antifungal activities of the petroleum ether and aqueous extracts of leaves and stems of Kalanchoe pinnata Linn (Crassulaceae). The qualitative phytochemical tests showed the presence of alkaloid, glycoside, gums, saponins, reducing sugar and tannins in the petroleum ether crude extract of Kalanchoe pinnata Linn while alkaloid, glycoside, steroid, saponins, tannins were present in the aqueous extract of Kalanchoe pinnata Linn. It was observed that both extracts of the studied plant possessed cytotoxic activity. In brine shrimp lethality bioassay, the LC50 (μg/ml) and LC90 (μg/ml) of the petroleum ether and aqueous extract of Kalanchoe pinnata Linn, were 25.12μg/ml& LC90: 177.83μg/ml respectively. The aqueous extract of the medicinal plant also showed lethality against the brine shrimp nauplii (LC50: 25.12μg/ml& LC90: 173.78μg/ml). Moreover, the extracts showed significant reducing power. It was also identified that the petroleum ether and aqueous extracts of Kalanchoe pinnata Linn showed antifungal activity. The obtained results provide a support for the use of this plant in traditional medicine. The plant studied can be a potential source of biologically active compounds as antifungal, anticancer agent and pesticide. [ABSTRACT FROM AUTHOR]

Background: Myopia is one of the most common causes of visual impairment worldwide.It is proved in earlier studies that the eye shape is different in myopic and nonmyopic children even at a very young age, with the former manifesting asymmetric axial globe elongation and the latter global expansion but limited information is available regarding hypermetropia. Aim: To find out the variations of axial ocular dimensions in relation to age, sex, height and to demonstrate any possible correlation of body mass index (BMI) in myopic hypermetropic and emmetropic patients. Settings: It is a cross-sectional observational study. Materials and Methods: All the patients attending eye OPD in the Regional Institute of Ophthalmology (R.I.O.), Medical College, Kolkata, West Bengal, India from June2010 to May 2011.Axial dimensions were measured by B-mode USG. Refractive status was measured.Age, gender, height and BMI were also observed. After collecting all the data,all the variables were summarised by descriptive statistics followed by correlation testing by Pearson's Correlation Coefficient r. Results: Height was positively correlated with axial length, anterior chamber depth, vitreous chamber depth ;age was positively correlated with axial length, vitreous chamber depth and negatively correlated with anterior chamber depth. Subjects with higher BMI tended to had refractions that were more hypermetropic. Conclusion: The findings of the present study can highlight not only the normal range of the different ocular parameters namely axial length, anterior chamber depth, vitreous chamber depth and lens thickness but their variation with age, gender, height and weight. [ABSTRACT FROM AUTHOR]

A low temperature aqueous approach was used to synthesize nanocrystalline, high surface area Mg 2 + substituted β-tricalcium phosphate (β-TCMP) to assess its potential use as a synthetic bone graft substitute. X-ray diffraction indicated that β-TCMP was the predominant crystalline phase formed. However, thermal analysis revealed the presence of a secondary amorphous phase which increased with increasing Mg 2 + concentration. Further analysis by Rietveld refinement indicated that the level of ionic substitution of Ca 2 + by Mg 2 + was significantly lower than the amount of Mg 2 + measured using elemental analysis, confirming the formation of a Mg 2 + rich secondary amorphous phase. MC3T3-E1 proliferation on substrates prepared using β-TCMP was assessed using the MTT assay. In comparison to commercially available β-TCP, increased proliferation was observed on samples prepared with 50% Mg, despite elevated Mg 2 + and PO 4 3 − concentrations in culture media. Alkaline phosphatase (ALP) activity and qRT-PCR were used to study the effect of varying Mg 2 + substitution on osteogenic differentiation. Cells cultured on β-TCMP substrates prepared with increased Mg 2 + concentrations expressed significantly increased levels of ALP activity and osteogenic genes such as, osteocalcin, collagen-1, and Runx2, in comparison to those cultured on commercially available β-TCP. [ABSTRACT FROM AUTHOR]

Bioremediation of crude oil contaminated soil is an effective process to clean petroleum contaminant from the environment. In this study, we isolated 39 native crude oil degrading bacteria from different crude oil contaminated soils. From 16S rDNA sequences, we confirmed that the isolated bacteria belong to the genera Lysinibacillus , Brevibacillus , Bacillus , Paenibacillus , Stenotrophomonas , Alcaligenes , Delftia , Achromobacter and Pseudomonas . Four most effective strains (designated as AS03, N108, N002 and N78) were used for batch culture and microcosm evaluation. Gas chromatography analysis, further confirmed that the strain AS03, N108, N002 and N78 were able to degrade crude oil under both shake culture and microcosm study. Under microcosm, the soil quality was further improved significantly in the treatments of BF1-Mix (N108-AS03) and BF2-Mix (N002-N78). The improvement of soil quality was also confirmed by earthworm mortality bioassay and in plant test on rice ( Oryza sativa) and mung ( Vigna radiata ). These findings demonstrated that the combine use of crude oil degrading bacteria along with nutrient supplements could revive crude oil contaminated soil effectively in large scale. [ABSTRACT FROM AUTHOR]

Highlights: [•] The novel microalga, S. obliquus SA1 was cultivated in large scale (open system). [•] SA1 showed tolerance to 35% CO2 concentration. [•] Biomass production at 35% CO2 was superior to the relevant literature reports. [•] Extracellular (periplasmic) carbonic anhydrase activity was more prominent in SA1. [•] Enhanced lipid and chlorophyll production was observed with increase in inlet CO2. [Copyright &y& Elsevier]

Abstract: Calcium phosphate (CaP) coatings have been studied to tailor the uncontrolled non-uniform corrosion of Mg based alloys while simultaneously enhancing bioactivity. The use of immersion techniques to deposit CaP coatings is attractive due to the ability of the approach to coat complex structures. In the current study, AZ31 substrates were subjected to various pretreatment conditions prior to depositing Sr2+ doped and undoped CaP coatings. It was hypothesized that the bioactivity and corrosion protection of CaP coatings could be improved by doping with Sr2+. Heat treatment to elevated temperatures resulted in the diffusion of alloying elements, Mg and Zn, into the pretreated layer. Sr2+ doped and undoped CaP coatings formed on the pretreated substrates consisted of biphasic mixtures of β-tricalcium phosphate (β-TCP) and hydroxyapatite (HA). Electrochemical corrosion experiments indicated that the extent of Sr2+ doping and pretreatment both influenced the corrosion protection. Cytotoxicity was evaluated with MC3T3-E1 mouse preosteoblasts and human mesenchymal stem cells (hMSCs). For both cell types, proliferation decreased upon increasing the Sr2+ concentration. However, both osteogenic gene and protein expression significantly increased upon increasing Sr2+ concentration. These results suggest that Sr2+ doped coatings are capable of promoting osteogenic differentiation on degradable Mg alloys, while also enhancing corrosion protection, in comparison to undoped CaP coatings. [Copyright &y& Elsevier]

Purpose: To noninvasively evaluate the effects of corneal hydration and collagen crosslinking (CXL) on the mechanical behavior of the cornea. Setting: Cleveland Clinic Cole Eye Institute, Cleveland, Ohio, USA. Design: Experimental study. Methods: An optical coherence elastography (OCE) technique was used to measure the displacement behavior of 5 pairs of debrided human donor globes in 3 serial states as follows: edematous, normal thickness, and after riboflavin–ultraviolet-A–mediated CXL. During micromotor-controlled axial displacements with a curved goniolens at physiologic intraocular pressure (IOP), serial optical coherence tomography scans were obtained to allow high-resolution intrastromal speckle tracking and displacement measurements over the central 4.0 mm of the cornea. Results: With no imposed increase in IOP, the mean lateral to imposed axial displacement ratios were 0.035 μm/μm ± 0.037 (SD) in edematous corneas, 0.021 ± 0.02 μm/μm in normal thickness corneas, and 0.014 ± 0.009 μm/μm in post-CXL corneas. The differences were statistically significant (P<.05, analysis of variance) and indicated a 40% increase in lateral stromal resistance with deturgescence and a further 33% mean increase in relative stiffness with CXL. Conclusions: Serial perturbations of the corneal hydration state and CXL had significant effects on corneal biomechanical behavior. With an axially applied stress from a nonapplanating contact lens, displacements along the direction of the collagen lamellae were 2 orders of magnitude lower than axial deformations. These experiments show the ability of OCE to quantify clinically relevant mechanical property differences under physiologic conditions. Financial Disclosures: Proprietary or commercial disclosures are listed after the references. [ABSTRACT FROM AUTHOR]

Purpose: To theoretically compare the corneal stress distribution of laser in situ keratomileusis (LASIK) with the stress distribution of small-incision lenticule extraction. Setting: Cleveland Clinic Cole Institute, Cleveland, and The Ohio State University, Columbus, Ohio, USA. Design: Computational modeling study. Methods: A finite-element anisotropic collagen fiber–dependent model of myopic surgery using patient-specific corneal geometry was constructed for LASIK, small-incision lenticule extraction, and a geometry analog model with unaltered material properties from preoperative but with postoperative geometry including thickness. Surgical parameters, magnitude of myopic correction, LASIK flap thickness, and lenticule depth in small-incision lenticule extraction were varied. Two sets of models, 1 with uniform and 1 with depth-dependent material properties, were constructed. Results: Stress distribution between small-incision lenticule extraction simulations and the geometry analog model were similar. In contrast, LASIK consistently reduced stress in the flap and increased stress in the residual stromal bed (RSB) compared with the geometry analog model. An increase in flap thickness or lenticule depth resulted in a greater increase in RSB stress in the LASIK model than in the small-incision lenticule extraction model. Conclusions: Small-incision lenticule extraction may present less biomechanical risk to the residual bed of susceptible corneas than comparable corrections involving LASIK flaps. Deeper corrections in the stroma may be possible in small-incision lenticule extraction without added risk for ectasia. Financial Disclosures: Proprietary or commercial disclosures are listed after the references. [ABSTRACT FROM AUTHOR]

Purpose: To test the hypothesis that spatially selective corneal stromal stiffening can alter corneal astigmatism and assess the effects of treatment orientation, pattern, and material model complexity in computational models using patient-specific geometries. Setting: Cornea and Refractive Surgery Service, Academic Eye Institute, Cleveland, Ohio, USA. Design: Computational modeling study. Methods: Three-dimensional corneal geometries from 10 patients with corneal astigmatism were exported from a clinical tomography system (Pentacam). Corneoscleral finite element models of each eye were generated. Four candidate treatment patterns were simulated, and the effects of treatment orientation and magnitude of stiffening on anterior curvature and aberrations were studied. The effect of material model complexity on simulated outcomes was also assessed. Results: Pretreatment anterior corneal astigmatism ranged from 1.22 to 3.92 diopters (D) in a series that included regular and irregular astigmatic patterns. All simulated treatment patterns oriented on the flat axis resulted in mean reductions in corneal astigmatism and depended on the pattern geometry. The linear bow-tie pattern produced a greater mean reduction in astigmatism (1.08 D ± 0.13 [SD]; range 0.74 to 1.23 D) than other patterns tested under an assumed 2-times increase in corneal stiffness, and it had a nonlinear relationship to the degree of stiffening. The mean astigmatic effect did not change significantly with a fiber- or depth-dependent model, but it did affect the coupling ratio. Conclusions: In silico simulations based on patient-specific geometries suggest that clinically significant reductions in astigmatism are possible with patterned collagen crosslinking. Effect magnitude was dependent on patient-specific geometry, effective stiffening pattern, and treatment orientation. Financial Disclosures: Proprietary or commercial disclosures are listed after the references. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the performance of corneal hysteresis (CH), corneal resistance factor, and 16 investigator-derived Ocular Response Analyzer (ORA) variables in distinguishing keratoconus (KC) from the nondiseased state. Design: Retrospective case series. Participants: Fifty-four eyes of 27 unaffected patients and 49 eyes of 25 KC patients from the Instituto de Olhos, Rio de Janeiro, Brazil. Methods: Sixteen candidate variables were derived from exported ORA signals to characterize putative indicators of biomechanical behavior. Area under the receiver operating characteristic curve (AUC) and the Z statistic were used to compare diagnostic performance. Main Outcome Measures: Discriminant value of standard and derived ORA variables as measured by AUC. Results: Fifteen of 16 candidate variables performed significantly better than chance (AUC, >0.5) at discriminating KC. Diagnostic performance was greatest for a custom variable related to the depth of deformation as defined by the minimum applanation signal intensity during corneal deformation (concavitymin; mean AUC ± standard error, 0.985±0.002) and a new measure incorporating the pressure-deformation relationship of the entire response cycle (hysteresis loop area, 0.967±0.002). Z statistics assessing the discriminative value of each of the top 5 variables demonstrated superiority to CH (AUC, 0.862±0.002). Concavitymin had the best overall predictive accuracy (cutoff value, 50.37; 94.9% sensitivity, 91.7% specificity, and 93.2% test accuracy), and the top 4 variables demonstrated the most consistent relationships to KC severity. Conclusions: Investigator-derived ORA variables related to the depth of deformation and the pressure-deformation relationship demonstrated very high test accuracy for detecting the presence of KC. Beyond their diagnostic value, the candidate variables described in this report provide mechanistic insight into the nature of the ORA signal and the characteristic changes in corneal dynamics associated with KC. [ABSTRACT FROM AUTHOR]