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Fluorinated drugs occupy a large and growing share of the pharmaceutical market. Here, we explore high-frequency, 60 to 111 kHz, 19F magic-angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy for the structural characterization of fluorinated active pharmaceutical ingredients in commercial formulations of seven blockbuster drugs: Celebrex, Cipro, Crestor, Levaquin, Lipitor, Prozac, and Zyvox. 19F signals can be observed in a single scan, and spectra with high signal-to-noise ratios can be acquired in minutes. 19F spectral parameters, such as chemical shifts and line widths, are sensitive to both the nature of the fluorine moiety and the formulation. We anticipate that the fast 19F MAS NMR-based approach presented here will be valuable for the rapid analysis of fluorine-containing drugs in a wide variety of formulations.

Purpose To develop a free-breathing whole-heart isotropic-resolution 3D late gadolinium enhancement (LGE) sequence with Dixon-encoding, which provides co-registered 3D grey-blood phase-sensitive inversion-recovery (PSIR) and complementary 3D fat volumes in a single scan of Methods A free-breathing 3D PSIR LGE sequence with dual-echo Dixon readout with a variable density Cartesian trajectory with acceleration factor of 3 is proposed. Image navigators are acquired to correct both inversion recovery (IR)-prepared and reference volumes for 2D translational respiratory motion, enabling motion compensated PSIR reconstruction with 100% respiratory scan efficiency. An intermediate PSIR reconstruction is performed between the in-phase echoes to estimate the signal polarity which is subsequently applied to the IR-prepared water volume to generate a water grey-blood PSIR image. The IR-prepared water volume is obtained using a water/fat separation algorithm from the corresponding dual-echo readout. The complementary fat-volume is obtained after water/fat separation of the reference volume. Ten patients (6 with myocardial scar) were scanned with the proposed water/fat grey-blood 3D PSIR LGE sequence at 1.5 T and compared to breath-held grey-blood 2D LGE sequence in terms of contrast ratio (CR), contrast-to-noise ratio (CNR), scar depiction, scar transmurality, scar mass and image quality. Results Comparable CRs (p = 0.98, 0.40 and 0.83) and CNRs (p = 0.29, 0.40 and 0.26) for blood-myocardium, scar-myocardium and scar-blood respectively were obtained with the proposed free-breathing 3D water/fat LGE and 2D clinical LGE scan. Excellent agreement for scar detection, scar transmurality, scar mass (bias = 0.29%) and image quality scores (from 1: non-diagnostic to 4: excellent) of 3.8 ± 0.42 and 3.6 ± 0.69 (p > 0.99) were obtained with the 2D and 3D PSIR LGE approaches with comparable total acquisition time (p = 0.29). Similar agreement in intra and inter-observer variability were obtained for the 2D and 3D acquisition respectively. Conclusion The proposed approach enabled the acquisition of free-breathing motion-compensated isotropic-resolution 3D grey-blood PSIR LGE and fat volumes. The proposed approach showed good agreement with conventional 2D LGE in terms of CR, scar depiction and scan time, while enabling free-breathing acquisition, whole-heart coverage, reformatting in arbitrary views and visualization of both water and fat information.

Purpose To implement a free-breathing sequence for simultaneous quantification of T 1 , T 2 , and T 2 ∗ for comprehensive tissue characterization of the myocardium in a single scan using a multi-gradient-echo readout with saturation and T 2 preparation pulses. Methods In the proposed Saturation And T 2 -prepared Relaxometry with Navigator-gating (SATURN) technique, a series of multi-gradient-echo (GRE) images with different magnetization preparations was acquired during free breathing. A total of 35 images were acquired in 26.5 ± 14.9 seconds using multiple saturation times and T 2 preparation durations and with imaging at 5 echo times. Bloch simulations and phantom experiments were used to validate a 5-parameter fit model for accurate relaxometry. Free-breathing simultaneous T 1 , T 2 , and T 2 ∗ measurements were performed in 10 healthy volunteers and 2 patients using SATURN at 3T and quantitatively compared to conventional single-parameter methods such as SASHA for T 1 , T 2 -prepared bSSFP, and multi-GRE for T 2 ∗ . Results Simulations confirmed accurate fitting with the 5-parameter model. Phantom measurements showed good agreement with the reference methods in the relevant range for in vivo measurements. Compared to single-parameter methods comparable accuracy was achieved. SATURN produced in vivo parameter maps that were visually comparable to single-parameter methods. No significant difference between T 1 , T 2 , and T 2 ∗ times acquired with SATURN and single-parameter methods was shown in quantitative measurements (SATURN T 1 = 1573 ± 86 ms , T 2 = 33.2 ± 3.6 ms , T 2 ∗ = 25.3 ± 6.1 ms ; conventional methods: T 1 = 1544 ± 107 ms , T 2 = 33.2 ± 3.6 ms , T 2 ∗ = 23.8 ± 5.5 ms ; P > . 2 ) CONCLUSION: SATURN enables simultaneous quantification of T 1 , T 2 , and T 2 ∗ in the myocardium for comprehensive tissue characterization with co-registered maps, in a single scan with good agreement to single-parameter methods.

Measurements of singlet spin order decay rates are time consuming due to the long-lived nature of this form of order and the typical pseudo-2D mode of acquisition. Additionally, this acquisition modality is not ideal for experiments run on hyperpolarized order because of the single-shot nature of hyperpolarization techniques. We present a methodology based on spatial encoding that not only significantly reduces the duration of these experiments but also confers compatibility using spin hyperpolarization techniques. The method condenses in a single shot the variable delay array used to measure decay rates in conventional pseudo-2D relaxation experiments. This results in a substantial time saving factor and, more importantly, makes the experiment compatible with hyperpolarization techniques since only a single hyperpolarized sample is required. Furthermore, the presented method, besides offering savings on time and costs, avoids reproducibility concerns associated with repetition in the hyperpolarization procedure. The method accelerates the measurement and characterization of singlet order decay times, and, when coupled with hyperpolarization techniques, can facilitate the quest for systems with very long decay times.

This paper describes an uncertainty evaluation for axial location-dependent cutting edge radius and angle values extracted from structured light scans of a variable pitch endmill. Two cases are evaluated: 1) a single scan of the endmill is performed and that scan is manually fit five times to record the cutting edge geometry for all teeth on the endmill; and 2) five scans of the endmill are performed and each scan is manually fit a single time. Both cases therefore include five manual fits. The standard deviations in radius and angle values are used to represent the statistical uncertainty and the two cases are compared. The mean standard deviations in radius are 0.005 mm and 0.007 mm; the mean standard deviations in angle are 0.066 deg and 0.092 deg. As expected, the uncertainties are higher with additional scans. The scan results are then used in a time-domain simulation to predict the cutting force profiles for the variable pitch endmill. It is shown that the two cases provide similar agreement between prediction and measurement due to the small measurement uncertainties.

This work develops the general concept lattice for the problem concerning categorisation of objects according to their properties. Unlike the conventional approaches, such as the formal concept lattice and the rough set lattice, the general concept lattice is designed to adhere to the general principle that the information content should be invariant regardless how the variables/parameters are presented. Here, one will explicitly demonstrate the existence of such a construction by a sequence of fulfilments compatible with the conventional lattice structure. The general concept lattice promises to be a comprehensive categorisation for all the distinctive object classes according to whatever properties they are equipped with. It will be shown that one can always regain the formal concept lattice and rough set lattice from the general concept lattice. One also speaks of the tractability of the general concept lattice for both its lattice structure and logical content. The general concept lattice permits a feasible construction that can be completed in a single scan of the formal context, though the conventional formal-concept lattice and rough-set lattice can be regained from the general concept lattice. The logic implication deducible from the general concept lattice takes the form of μ 1 → μ 2 where μ 1 , μ 2 ∈ M ⁎ are composite attributes out of the concerned formal attributes M. Remarkable is that with a single formula based on the contextual truth 1 η one can deduce all the implication relations extractable from the formal context. For concreteness, it can be shown that any implication A → B ( A , B being subsets of the formal attributes M) discussed in the formal-concept lattice corresponds to a special case of μ 1 → μ 2 by means of μ 1 = ∏ A and μ 2 = ∏ B . Thus, one may elude the intractability due to searching for the Guigues-Duquenne basis appropriate for the implication relations deducible from the formal-concept lattice. Likewise, one may identify those μ 1 → μ 2 where μ 1 = ∑ A and μ 2 = ∑ B with the implications that can be acquired from the rough-set lattice. (Here, the product ∏ stands for the conjunction and the summation ∑ the disjunction.)

The brain’s vasculature is essential for brain health and its dysfunction contributes to the onset and development of many dementias and neurological disorders. While numerous in vivo imaging techniques exist to investigate cerebral haemodynamics in humans, phase-contrast magnetic resonance imaging (MRI) has emerged as a reliable, non-invasive method of quantifying blood flow within intracranial vessels. In recent years, an advanced form of this method, known as 4D flow, has been developed and utilised in patient studies, where its ability to capture complex blood flow dynamics within any major vessel across the acquired volume has proved effective in collecting large amounts of information in a single scan. While extremely promising as a method of examining the vascular system’s role in brain-related diseases, the collection of 4D data can be time-consuming, meaning data quality has to be traded off against the acquisition time. Here, we review the available literature to examine 4D flow’s capabilities in assessing physiological and pathological features of the cerebrovascular system. Emerging techniques such as dynamic velocity-encoding and advanced undersampling methods, combined with increasingly high-field MRI scanners, are likely to bring 4D flow to the forefront of cerebrovascular imaging studies in the years to come.

Background & ObjectivesCharacterizing the progression of coronary atherosclerosis is a critical public health goal. The most common quantitative summary, the CAC score, is modelled by a variety of statistical methods, both as a predictor of coronary events and as an outcome of behavioral and population-specific risk factors. Little attempt has been made, however, to ground these statistical models in the underlying physiology of arterial aging, which would allow us to describe the onset and growth of CAC over a patient's life.MethodsUsing a generative growth model for arterial plaque accumulation, we identify severe under-estimation in the age of initial onset and rate of progression (doubling time) of CAC growth with standard ln(CAC + 1) or ln(CAC | CAC > 0) models, and use this growth model to motivate new statistical approaches to CAC using logistic and log-linear mixture regressions. We compare statistical models directly by computing their average parameter biases using 540 growth trajectory simulations (113,760 patients, 268,200 observations).ResultsWhile all models used can successfully estimate the influence of risk factors with minimal bias, we demonstrate substantial improvements in predictive accuracy in the timing of CAC onset and progression with logistic regression and linked hurdle-lognormal mixture regression, compared with standard ln(CAC + 1) or ln(CAC | CAC > 0) models.ConclusionsUsing models that can account for patient-specific onset and progression rates, accurate descriptions of CAC trajectories can be made even in cross-sectional (single scan per patient) designs, with substantial clinical and epidemiological utility.

OBJECTIVES As part of the 75-Selenium homocholic acid taurine (SeHCAT) study, counts are acquired as a baseline to allow the calculation of the retention at 7 days. In this work, we evaluated whether it was possible to replace the baseline image with a predictive model based on the patient's height and weight. METHOD Height and weight data from 723 patients scanned at three hospitals using seven gamma cameras were compiled. A number of different models were trialled, with fitting parameters determined by regression. A predictive model based on height and logarithm of weight was found to have the best correlation with the measured counts in the 3-h study. RESULTS There was a strong correlation (R2 = 0.91) between the measured counts and the predicted counts using a model based on height and logarithm of weight. Treating the standard SeHCAT test result as the gold standard, the test result when predicted baseline counts were used had a sensitivity and specificity of 97.5 and 98.0%, respectively, at a threshold of 15%. In total 694/723 (96.0%) of patients had no change to their severity grading when using the predicted baseline counts. CONCLUSION This work presents a model that was able to predict the counts in the 3 h SeHCAT study for patients on seven gamma cameras. This can enable a single scan study, giving significant savings to patient and staff time and imaging resources.

A straightforward digital method of evaluating wear volume loss is described. This method allows the measurement of the wear by analyzing only the three-dimensional scan dataset of the worn specimen without needing a separate baseline scan. Compared to the conventional method, involving superimposition of the two datasets scanned before and after the wear test, this method can reduce labor and accuracy errors caused by repeated scans and superimposition procedures. Further, this analysis can be conducted using free computer-aided design software, which makes it more efficient for the analysis of wear volume loss of restorative materials.

Multiple image averaging (MIA) is a new approach to improve OCT angiography (OCTA) imaging. The aim of this work was to analyze the impact of MIA on image quality and quantitative OCTA parameters. Twenty eyes from 20 healthy volunteers (55.65 ± 14.8 years) were prospectively enrolled. Imaging was performed using two commercially available OCTA devices (Canon OCT HS-100, Optovue AngioVue) using a uniform imaging protocol. Each participant had two single scans of the macula (3 × 3mm, Canon and Optovue) as well as five continuous single scan imaging procedures (3 × 3mm each) using the Canon device. Three out of five of these images with highest quality were manually chosen and then automatically processed by the Canon device using MIA. The superficial retinal plexus of the single scans and of MIA images was analyzed with regard to the device’ own image quality scores (IQS), peak signal-to-noise ratio (PSNR), the size of the foveolar avascular zone (FAZ), and vessel density (VD). Image acquisition times were recorded. Parameters were compared between the devices and the different imaging protocols. Average acquisition time was significantly higher for the MIA compared with the single measurements (29.09 ± 10.19 seconds (s) (MIA) vs. 5.56 ± 2.17 s (Canon single scan) vs. 20.28 ± 6.81 s (Optovue) (p < 0.001)). IQS showed no significant differences between the devices and between the recording protocols. PSNR was 12.38 ± 0.20 (Canon single scan), 13.01 ± 0.36 (Canon MIA), and 14.34 ± 0.60 (Optovue) (p < 0.001 between the groups). Mean FAZ area in Canon single scans was 0.29 ± 0.06 mm2, 0.27 ± 0.07 mm2 using MIA, and 0.27 ± 0.08 mm2 using the Optovue device. There was no significant difference between mean FAZ measurements before and after averaging (Canon single scan vs. MIA, p = 0.168). VD of the parafoveal area using MIA was significantly lower compared with both single scans (p < 0.001). MIA can improve PSNR, but it also reduces imaging speed and significantly affects VD measurements. Therefore, when comparing OCTA data, the use of uniform imaging protocols is required.

This paper considers discovering frequent itemsets in transactional databases and addresses the time complexity problem by using high performance computing (HPC). Three HPC versions of the Single Scan (SS) algorithm are proposed. The first one (GSS) implements SS on a GPU (Graphics Processing Unit) architecture using an efficient mapping between thread blocks and the input data. The second approach (CSS) implements SS on a cluster architecture by scheduling independent jobs to workers in a cluster. The third, (CGSS) accelerates the frequent itemset mining process by using multiple cluster nodes equipped with GPUs. Moreover, three partitioning strategies are proposed to reduce GPU thread divergence and cluster load imbalance. Results show that CGSS outperforms SS, GSS, and CSS in terms of speedup. Specifically, CGSS provides up to a 350 times speedup for low minimum support values on large datasets. GCSS demonstrably outperforms the state-of-the-art HPC-based algorithms on big databases.

Forest disruption caused by pest insects is a common disaster occurring in plantations, and is a threatening factor to forest health. Therefore, a precise method for monitoring individual tree health and estimating disturbance severity is urgently needed. Theoretically, terrestrial laser scanning (TLS) is a promising tool in high resolution remote sensing, which can provide information regarding the structural change of the affected trees with millimeter precision. However, few studies have explored the potential of TLS application in this field, especially when using only mono-temporal data. In this study, a single-scan TLS data-based method was developed and validated to classify defoliation at both individual-tree scale and plot scale. The objects were classified into three classes: healthy/slightly defoliated, moderately defoliated and severely defoliated. Sixty features were extracted from TLS data and optimized to six (individual-tree scale) and five (plot scale) explanatory variables by using a Random Forest method to accomplish the classification. By this approach, individual trees can be classified into three defoliation levels with 80% overall accuracy (kappa value 0.70), while plot-scale classification had 94% overall accuracy (kappa value 0.91). Point distribution characteristics proposed in this method were among the most important features for defoliation estimation. Evidently, the methods presented in this study are capable of providing satisfactory estimates of defoliation severity, and supporting a precise inventory and monitoring of forest health.

This pilot study aimed to prove the complementary value of a novel Gallium-labeled heterodimeric peptide, Ga-NOTA-3P-TATE-RGD, in detection and evaluation of tumors with somatostatin receptor subtype 2 or integrin αvβ3 overexpression, including non-small cell lung cancer (NSCLC), small-cell lung cancer (SCLC), neuroendocrine tumor (NET), and neuroendocrine carcinoma (NEC).With institute review board approval and written informed consent, 32 patients with pathologically diagnosed lung cancer (18 NSCLC, 14 SCLC) and 12 patients with neuroendocrine neoplasm (8 NET, 4 NEC) patients were recruited to undergo Ga-NOTA-3P-TATE-RGD PET/CT. For comparison, the NSCLC patients also underwent Ga-NOTA-TATE PET/CT, the SCLC patients underwent Ga-NOTA-RGD PET/CT, and the neuroendocrine neoplasm patients underwent F-FDG PET/CT within 3 days. The maximum standardized uptake value (SUV) of the primary tumor (T) and mean SUV of the blood pool (B) were measured, and the T/B ratios were calculated for comparison.In the primary tumors of NSCLC, the T/B ratios of Ga-NOTA-3P-TATE-RGD were significantly higher than those of Ga-NOTA-TATE (4.54 ± 3.00 versus 4.10 ± 2.83, P = 0.0058). In SCLC, the T/B ratios of Ga-NOTA-3P-TATE-RGD were significantly higher than those of Ga-NOTA-RGD (6.06 ± 6.09 versus 2.65 ± 1.19, P = 0.0344). In NET, the T/B ratios of Ga-NOTA-3P-TATE-RGD were 36.13 ± 33.84, significantly higher than those of F-FDG (2.91 ± 1.71, P = 0.0234). In NEC, there were no significant difference between the T/B ratios of Ga-NOTA-3P-TATE-RGD (4.80 ± 0.85) and those of F-FDG (3.56 ± 0.74, P = 0.1833).This proof-of-concept study preliminarily demonstrates the efficacy of the dual targeting Ga-NOTA-3P-TATE-RGD PET/CT in the evaluation of lung cancer and neuroendocrine neoplasm in a single scan.

Objectives The goal of this study was to evaluate the diagnostic accuracy of stress computed tomography myocardial perfusion (CTP) for the detection of functionally significant coronary artery disease (CAD) by using invasive coronary angiography (ICA) plus invasive fractional flow reserve (FFR) as the reference standard in consecutive intermediate- to high-risk symptomatic patients. Background Stress CTP recently emerged as a potential strategy to combine the anatomic and functional evaluation of CAD in a single scan. Methods A total of 100 consecutive symptomatic patients scheduled for ICA were prospectively enrolled. All patients underwent rest coronary computed tomography angiography (CTA) followed by stress static CTP with a whole-heart coverage CT scanner (Revolution CT, GE Healthcare, Milwaukee, Wisconsin). Diagnostic accuracy and overall effective dose were assessed and compared versus those of ICA and invasive FFR. Results The prevalence of obstructive CAD and functionally significant CAD were 69% and 44%, respectively. Coronary CTA alone demonstrated a per-vessel and per-patient sensitivity, specificity, negative predictive value, positive predictive value, and accuracy of 98%, 76%, 99%, 63%, and 83% and of 98%, 54%, 96%, 68%, and 76%, respectively. Combining coronary CTA with stress CTP, per-vessel and per-patient sensitivity, specificity, negative predictive value, positive predictive value, and accuracy were 91%, 94%, 96%, 86%, and 93% and 98%, 83%, 98%, 86%, and 91%, with a significant improvement in specificity, positive predictive value, and accuracy in both models. The mean effective dose for coronary CTA and stress CTP were 2.8 ± 1.4 mSv and 2.5 ± 1.1 mSv. Conclusions The inclusion of stress CTP for the evaluation of patients with an intermediate to high risk for CAD is feasible and improved the diagnostic performance of coronary CTA for detecting functionally significant CAD.

Synthetic magnetic resonance imaging (MRI) allows the production of images with any contrast from a single scan after quantification. The combined T2-weighted image (T2WI) and fluid-attenuated inversion recovery (FLAIR) image is expected to have an improved contrast between the normal-appearing white matter (WM) and WM lesion (WML). The purpose of this study was to determine whether optimal T2 contrast-weighted images (SyFLAIR3) comprising the combined T2WI and FLAIR image generated using synthetic MRI could improve contrast in the WM region. Numerical simulations were performed to estimate the contrast-to-noise ratio (CNR) between the WM and WML and cerebrospinal fluid (CSF) ratio at any echo time (TE) using SyFLAIR3. The CNR and CSF ratio for SyFLAIR3 was compared with those for FLAIR and double inversion recovery (DIR) images in ten volunteers. In numerical simulations, the CNR for SyFLAIR3 was increased in the T2WI and FLAIR images with long TEs, and the CSF ratio was decreased on those with short TEs. An in vivo study indicated that the CNR for SyFLAIR3 using T2WI and FLAIR images with an optimized combination of TEs was significantly higher than those for FLAIR and DIR images; whereas, the CSF ratio for the optimized SyFLAIR3 was not significantly different from that for the FLAIR images. The use of SyFLAIR3 improves the contrast within the region of the WM without the need for additional scanning in synthetic MRI.

A single scan has been performed in Differential Scanning Calorimetry (DSC) at a heating rate of 15oC/min under non-isothermal conditions to investigate the crystallization kinetics of glassy Se90Sb10-xAgx alloys (where x = 2, 4, 6, 8). For this purpose, Handerson’s theory based on non-isothermal method for thermal analysis of single-scan DSC data has been used. The activation energy of crystallization and order parameter has been determined and composition dependence of these parameters has been discussed.

Cardiovascular magnetic resonance is a versatile tool that enables noninvasive characterization of cardiac tissue structure and function. Parametric mapping techniques have allowed unparalleled differentiation of pathophysiological differences in the myocardium such as the delineation of myocardial fibrosis, hemorrhage, and edema. These methods are increasingly used as part of a tool kit to characterize disease states such as cardiomyopathies and coronary artery disease more accurately. Currently conventional mapping techniques require separate acquisitions for T1 and T2 mapping, the values of which may depend on specifics of the magnetic resonance imaging system hardware, pulse sequence implementation, and physiological variables including blood pressure and heart rate. The cardiac magnetic resonance fingerprinting (cMRF) technique has recently been introduced for simultaneous and reproducible measurement of T1 and T2 maps in a single scan. The potential for this technique to provide consistent tissue property values independent of variables including scanner, pulse sequence, and physiology could allow an unbiased framework for the assessment of intrinsic properties of cardiac tissue including structure, perfusion, and parameters such as extracellular volume without the administration of exogenous contrast agents. This review seeks to introduce the basics of the cMRF technique, including pulse sequence design, dictionary generation, and pattern matching. The potential applications of cMRF in assessing diseases such as nonischemic cardiomyopathy are also briefly discussed, and ongoing areas of research are described.

Introduction Flattening of the trochlear tali is clinically observed as structural and functional changes advance in patients with hemarthropathy of the ankle. However, the degree of this flattening has not yet been quantified, and distribution of the morphological changes across the talus not yet defined. Materials and methods Chronologically sequential MR images of both a hemophilic patient group (N=5) and a single scan from a non-diseased, sex-matched, control group (N=11) were used to take four measurements of the trochlear talus morphology at three locations (medial, central and lateral) along the sagittal plane. Three ratios of interest were defined from these to assess whether the talar dome flattens with disease. The control group MRI measurements were validated against literature data obtained from CT scans or planar X-Rays. The influence of disease on talar morphology was assessed by direct comparison of the hemophilic cases with the control group. Results The values for all three ratios, in all locations, differed between the control and the hemophilic group. Flattening was indicated in the hemophilic group in the medial and lateral talus, but differences in the central talus were not statistically significant. Conclusions This work demonstrates that morphological assessment of the talus from MR images is similar to that from CT scans or planar X-Rays. Talar flattening does occur with hemarthropathy, especially at the medial and lateral edges of the joint surface. General flattening of the trochlear talus was confirmed in this small patient sample, however the degree and rate of change is unique to each ankle. This article is protected by copyright. All rights reserved.

Recently, polarization sensitive Second Harmonic Generation (pSHG) microscopy has become a powerful tool for the study of the noncenterosymmetric biological structures. This is due to the fact that pSHG has some intrinsically benefits such as high resolution and contrast, and it can also penetrate deeply inside the sample in a noninvasive manner. One drawback for the pSHG technique is that the imaging procedure is not fast enough to study in vivo samples or to monitor the dynamics of different tissues. This issue imposes some limitations on using the pSHG technique to study in vivo samples. Fortunately, recently Single Scan polarization sensitive Second Harmonic Generation (SS-pSHG) technique has been introduced as a fast alternative for the conventional pSHG technique. In this article, the results obtained from ex vivo biological samples of starch, human cornea and animal tendon have been compared in a pixel-to-pixel manner using pSHG and SS-pSHG techniques in forward direction. Even though the samples used here are ex vivo, the results of this study promise that the polarization sensitive SHG microscopy techniques have a great potential to study biological tissues in a noninvasive procedure. This issue is more important especially in the cases that samples are in vivo.

Urgent environmental challenges and emerging additive manufacturing (AM) technologies push research towards more performant and new materials. In the field of metallurgy, high entropy alloys (HEAs) have recently represented a topic of intense research because of their promising properties, such as high temperature strength and stability. Moreover, this class of multi-principal element alloys (MPEAs) have opened up researcher community to unexplored compositional spaces, making prosper literature of high-throughput methodologies and tools for rapidly screening large number of alloys. However, none of the methods has been aimed to design new MPEAs for AM process known as selective laser melting (SLM) so far. Here we conducted nanoindentation testing on single scan tracks of elemental powder blends and pre-alloyed powders after ball milling of AlTiCuNb and AlTiVNb. Results show that nanoindentation can represent an effective technique to gain information about phase evolution during laser scanning, contributing to accelerate the development of new MPEAs.

Objective: The epidemiology of sub-aneurysmal aortic dilatation (SAA) 25 - 29 mm is not fully understood, and the management of SAA is debated. Lack of evidence is particularly problematic in the screening setting. This study aimed to evaluate the long term outcome of men with screen detected SAAs, focusing on progression to an abdominal aortic aneurysm (AAA), and on the AAAs reaching the threshold diameter for surgical repair. Methods: Between 2006 and 2015, all 65 year old men with a screen detected SAA in middle Sweden were re-examined with ultrasound after five and 10 years. The primary outcomes were expansion to AAA >= 30 mm and progression to AAA >= 55 mm. Secondary outcomes were risk factors for progression, repair rate, and mortality. Results: A total of 1 020 65 year old men with a SAA were identified, of whom 940 (92.2%; 95% confidence interval 91.0 - 93.8) had follow up. The Kaplan-Meier estimated incidence of AAA >= 30 mm development after the five year follow up (which was de facto carried out after a mean of 4.9 years) was 65.8% (61.6 - 69.4), all < 55 mm. The corresponding KM-estimated incidence after the 10 year follow up (carried out after a mean of 11.9 years) was 95.1% (90.1 - 97.4), and 29.7% (18.0 - 39.7) reached >= 55 mm. All 41 SAAs eventually expanding to >= 55 mm were >= 30 mm at the five year follow up. Of these, 32 had surgical repair with 100% survival, six have scheduled repairs, and three (7.3%) were unfit for repair. The KM estimated all cause mortality rates at five and 10 years were 7.0% and 17.9%, respectively, with no proven AAA related deaths. Conclusion: A majority of SAAs eventually progress to an AAA, of which 30% are estimated to eventually reach the threshold for repair within 10 years. A follow up policy with an ultrasound examination after five years can safely and effectively identify those SAAs at risk of developing into clinically significant AAAs needing repair and may be considered for anyone with reasonably good life expectancy.

Frequent pattern mining (FPM) is one of the most important areas in the field of data mining. Several FPM algorithms have been proposed in the literature by many researchers. In most of the approaches, data set is scanned repeatedly in almost every steps of the algorithm that leads to high time complexity. That is why, processing huge amount of data using those algorithms may not be a suitable option. Hence, a novel FPM algorithm is proposed in this paper that improves efficiency by decreasing the time complexity as compared to classical frequent pattern mining algorithm. The proposed FPM algorithm converts the real-world data set into a binary matrix in a single scan, then join operation is performed to obtain the candidate itemsets. Further, AND operation is performed on the candidates to obtain frequent itemsets. Further more, using our proposed algorithm, interesting association rules can be derived.

Fast IPv4 scanning has enabled researchers to answer a wealth of security and networking questions. Yet, despite widespread use, there has been little validation of the methodology's accuracy, including whether a single scan provides sufficient coverage. In this paper, we analyze how scan origin affects the results of Internet-wide scans by completing three HTTP, HTTPS, and SSH scans from seven geographically and topologically diverse networks. We find that individual origins miss an average 1.6-8.4% of HTTP, 1.5-4.6% of HTTPS, and 8.3-18.2% of SSH hosts. We analyze why origins see different hosts, and show how permanent and temporary blocking, packet loss, geographic biases, and transient outages affect scan results. We discuss the implications for scanning and provide recommendations for future studies.

While many drugs and metabolites contain nitrogen, harnessing their diagnostic 15N NMR signature for their characterization is underutilized because of inherent detection difficulties. Here, we demonstrate how precise ultralow field signal amplification by reversible exchange (±0.2 mG) in conjunction parahydrogen and an iridium precatalyst of the form IrCl(COD)(NHC) with the coligand d9-benzylamine allows the naturally abundant 15N NMR signatures of pyridine, pyrazine, metronidazole, and acetonitrile to be readily detected at 9.4 T in single NMR observations through >50% 15N polarization levels. These signals allow for rapid and precise reagent quantification via a response that varies linearly over the 2-70 mM concentration range.

Research Highlights: The present study case investigates the differences occurring when tree&rsquo, s biophysical parameters are extracted through single and multiple scans. Scan sessions covered mountainous and hill regions of the Carpathian forests. Background and Objectives: We focused on analyzing stems, as a function of diameter at breast height (DBH) and the total height (H), at sample plot level for natural forests, with the purpose of assessing the potential for transitioning available methodology to field work in Romania. Materials and Methods: We performed single and multiple scans using a FARO Focus 3D X130 phase shift terrestrial laser scanner at 122kpts and 0.3:0.15 mm noise compression ratio, resulting in an average point density of 6pts at 10m. The point cloud we obtained underpinned the DBH and heights analysis. In order to reach values similar to those measured in the field, we used both the original and the segmented point clouds, postprocessed in subsamples of different radii. Results: Pearson&rsquo, s correlation coefficient above 0.8 for diameters showed high correlation with the field measurements. Diameter averages displayed differences within tolerances (0.02m) for 10 out of 12 plots. Height analysis led to poorer results. For both acquisition methods, the values of the correlation coefficient peaked at 0.6. The initial hypothesis that trees positioned at a distance equivalent to their height can be measured more precise, was not valid, no increase in correlation strength was visible for either heights or diameters as the distance from scanner varied (r = 0.52). Conclusions: With regard to tree biophysical parameters extraction, the acquisition method has no major influence upon visible trees. We emphasize the term &ldquo, visible&rdquo, as an increase in the number of acquisitions led to an increased number of detected trees (16% in old stands and 29% in young stands).

There are many diseases associated with lungs or thoracic cavity and the diagnosis of these diseases at once becomes difficult for any medical profusion. The most common way of screening done when the thoracic cavity comes into the picture is Chest Radiography. However, diagnosing multiple diseases from a single scan becomes difficult. This paper proposes an intelligent machine learning-based model which tries to detect 14 chest diseases out from a single radiograph with greater accuracy. This paper makes use of advanced deep learning techniques like neural networks, masking algorithms, etc. to assure higher performances.

In this paper, a novel network based on gated recurrent unit (GRU) is proposed for separating single-scan dual-tracer PET mixed images. Compared to conventional methods, this method can separate dual-tracer that are simultaneously injected or even labeled with the same marker, and do not require arterial blood input function. The proposed 4-layer network denoises the time activity curves (TACs) extracted from the dynamic dual-tracer reconstruction images with noise by pre-training the parameters in the first and second layer, and then uses TAC time information for dual-tracer separation. During the training stage, we optimize the network by minimizing the mean square error (MSE) objective function of the separated predicted value and ground truth. Monte Carlo is used to simulate the PET sampling environment with the mixed dual-tracer \({^{62}}\)Cu-ATSM+\({^{62}}\)Cu-PTSM and \({^{18}}\)F-FDG+\({^{11}}\)C-MET. Calculating the bias and variance to quantitatively analyze the results, we demonstrate that this method is more robust and better separation than the similar methods.

We pose 4 questions for the clinician diagnosing and monitoring glaucoma, and supply evidence-based answers. The first question is: "When do you perform a 10-2 (2-degree grid) visual field (VF) test?" We argue the best answer is: anyone you would do, or have done, a 24-2 (6-degree grid) VF on should have both a 24-2 and a 10-2 VF within the first 2 visits. Second, "When do you perform an optical coherence tomography (OCT) scan of the macula?" We argue that, if you are performing an OCT test, then it should include both the macula and disc, either as a single scan or as 2 scans, one centered on the macula and the other on the disc. Third, "How do you know if the VF and OCT tests agree?" The poor answer is, "I use summary statistics such as 24-2 mean deviation and global or quadrant average of retinal nerve fiber layer (RNFL) thickness." It is much better to topographically compare abnormal regions on the OCT to abnormal regions on the VF. Finally, the fourth question is: "When do you look at OCT images?" We argue that, at a minimum, the clinician should be directly examining an image of the circumpapillary RNFL, and this image should be sufficiently large and with sufficient resolution so that local damage can be seen, and the segmentation evaluated.

In vivo quantification of glutamate (Glu) and γ-aminobutyric acid (GABA) using MRS is often achieved using two separate sequences: a short-echo point resolved spectroscopy (PRESS) acquisition for Glu and a Mescher-Garwood PRESS (MEGA-PRESS) acquisition for GABA. The purpose of this study was to examine the agreement of Glu and Glx (the combined signal of glutamate + glutamine) quantified from two different GABA-edited MEGA-PRESS acquisitions (GABA plus macromolecules, GABA+, TE = 68 ms, and macromolecule suppressed, MMSup, TE = 80 ms) with Glu and Glx quantified from a short-echo PRESS (PRESS-35, TE = 35 ms) acquisition. Fifteen healthy male volunteers underwent a single scan session, in which data were acquired using the three acquisitions (GABA+, MMSup and PRESS-35) in both the sensorimotor and anterior cingulate cortices using a voxel size of 3 × 3 × 3 cm3 . Glx and Glu were quantified from the MEGA-PRESS data using both the OFF sub-spectra and the difference (DIFF) spectra. Agreement was assessed using correlation analyses, Bland-Altman plots and intraclass correlation coefficients. Glx quantified from the OFF sub-spectra from both the GABA+ and MMSup acquisitions showed poor agreement with PRESS-35 in both brain regions. In the sensorimotor cortex, Glu quantified from the OFF sub-spectra of GABA+ showed moderate agreement with PRESS-35 data, but this finding was not replicated in the anterior cingulate cortex. Glx and Glu quantified using the DIFF spectra of either MEGA-PRESS sequence were in poor agreement with the PRESS-35 data in both brain regions. In conclusion, Glx and Glu measured from MEGA-PRESS data generally showed poor agreement with Glx and Glu measured using PRESS-35.

One of the tenets of spine surgery is that if a joint is proven to be a pain generator, a fusion of the joint will most likely alleviate pain. Sacroiliac joint pain (SIJ) is very difficult to diagnose, as it manifests as back and leg pain and the diagnosis is not made just from a single scan or a test but from history, physical examination, imaging, and confirmatory injections. Modern techniques to fuse the SIJ via a minimally invasive, percutaneous placement of implants across the joint is being evaluated to be an excellent alternative to open, classic techniques. This chapter reviews the nuances of this technique.

Purpose Most clinical MR examinations require acquisition of different image contrasts. For abdominal exams, the scans are conventionally performed as separate acquisitions using respiratory gating or repeated breath holding, which can be time-inefficient and challenging for patients. Here, a hybrid imaging approach is described that creates T2 - and T1 -weighted images from a single scan and allows for free-breathing acquisition. Theory and methods T2 -weighted data is collected using 3D fast spin-echo (FSE) acquisition with motion-robust radial stack-of-stars sampling. The wait time between the FSE trains is used to acquire T1 -weighted gradient-echo (GRE) data. Improved robustness is achieved by extracting a respiratory signal from the GRE data and using it for motion-weighted reconstruction. Results As validated in simulations and phantom scans, GRE acquisition in the wait time has minor effect on the signal strength and contrast. Volunteer scans at 1.5T showed that T2 - and T1 -weighted hybrid imaging is feasible during free-breathing. Furthermore, it has been demonstrated in a patient that hybrid imaging with T1 -weighted Dixon acquisition is possible. Conclusion The described hybrid sequence enables comprehensive T2 - and T1 -weighted imaging in a single scan. In addition to free-breathing abdominal examination, it promises value for clinical applications that are frequently affected by motion artifacts.