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The primary objective of the Ras Tanura Refinery Clean Fuels Project is to enable the Ras Tanura refinery--the largest refinery in Saudi Arabia--to produce transportation fuels that will be compliant [...]

Objective: To determine whether an irrigatedunbalanced antenna can create larger ablations than a conventional microwave antenna without overheating. Method: The microwave and ablation characteristics of a previously published multi-ring slot array (MRSA) ablation antenna, optimized for intravascular environments, were compared with a dielectric-insulated monopole antenna with no matching or balancing elements, creating the unbalanced monopole antenna. The two antennae were numerically simulated in an intravascular environment and tested inside a gel phantom for five repetitions for comparison. Each antenna assembly was $\text{900 mm}$ long, with a $\text{2.45 GHz}$ ablatingfrequency, with a microwave input power of $\text{60 W}$ for $\text{120 s}$ via a patient cable. Results: Gel experiments were consistent with numerical simulations, with the unbalanced monopole antenna possessing better microwave and ablative characteristics than the MRSA in a biological environment. Microwave input power to the device connector was attenuated from $\text{60 W}$ to $\text{40 W}$ due to patient cable losses. Removing matching elements improved input impedance at the test plane (Real, 52.20 $\pm$ $5.90 \;\Omega$ vs. 74.22 $\pm$ $43.25 \;\Omega$, p = 0.05648; Imaginary, −23.50 $\pm$ $2.63 \;\Omega$ vs. 14.92 $\pm$ $51.10 \;\Omega$, p = 0.1333) and the return loss (−12.79 $\pm$ $\text{0.45 dB}$ vs. 6.51 $\pm$ $\text{0.25 dB}$, p = $2.521 \times 10^{-7}$). The unbalanced monopole antenna created wide (18.28 $\pm$ $\text{0.57 mm}$ vs. 13.38 $\pm$ $\text{0.60 mm}$, p = $2.482 \times 10^{-5}$) and deeper (11.87 $\pm$ $\text{0.88 mm}$ vs. 9.41 $\pm$ $\text{0.98 mm}$, p = $1.616 \times 10^{-2}$) ablation lesions than the MRSA. Clinical Impact: Removing elements from an MRSA created an unbalanced monopole antenna that creates larger ablation lesions with improved microwave characteristics.

A generic out-of-sample error estimate is proposed for $M$-estimators regularized with a convex penalty in high-dimensional linear regression where $(\boldsymbol{X},\boldsymbol{y})$is observed and the dimension $p$and sample size $n$are of the same order. The out-of-sample error estimate enjoys a relative error of order $n^{-1/2}$in a linear model with Gaussian covariates and independent noise, either non-asymptotically when $p/n\le \gamma $or asymptotically in the high-dimensional asymptotic regime $p/n\to \gamma ^{\prime}\in (0,\infty )$. General differentiable loss functions $\rho $are allowed provided that the derivative of the loss is 1-Lipschitz; this includes the least-squares loss as well as robust losses such as the Huber loss and its smoothed versions. The validity of the out-of-sample error estimate holds either under a strong convexity assumption, or for the L1-penalized Huber M-estimator and the Lasso under a sparsity assumption and a bound on the number of contaminated observations. For the square loss and in the absence of corruption in the response, the results additionally yield $n^{-1/2}$-consistent estimates of the noise variance and of the generalization error. This generalizes, to arbitrary convex penalty and arbitrary covariance, estimates that were previously known for the Lasso.

Understanding kidney disease relies on defining the complexity of cell types and states, their associated molecular profiles and interactions within tissue neighbourhoods1. Here we applied multiple single-cell and single-nucleus assays (>400,000 nuclei or cells) and spatial imaging technologies to a broad spectrum of healthy reference kidneys (45 donors) and diseased kidneys (48 patients). This has provided a high-resolution cellular atlas of 51 main cell types, which include rare and previously undescribed cell populations. The multi-omic approach provides detailed transcriptomic profiles, regulatory factors and spatial localizations spanning the entire kidney. We also define 28 cellular states across nephron segments and interstitium that were altered in kidney injury, encompassing cycling, adaptive (successful or maladaptive repair), transitioning and degenerative states. Molecular signatures permitted the localization of these states within injury neighbourhoods using spatial transcriptomics, while large-scale 3D imaging analysis (around 1.2 million neighbourhoods) provided corresponding linkages to active immune responses. These analyses defined biological pathways that are relevant to injury time-course and niches, including signatures underlying epithelial repair that predicted maladaptive states associated with a decline in kidney function. This integrated multimodal spatial cell atlas of healthy and diseased human kidneys represents a comprehensive benchmark of cellular states, neighbourhoods, outcome-associated signatures and publicly available interactive visualizations.

Introduction Blended instruction is a powerful tool that is still underused in adult and continuing technical education. In this article, I share my experience and the process Kim Kaycee and [...]

ABSTRACTHistorical information is the key input for risk analysis with respect to developing the risk model as well as in the risk management process, i.e. identification of effective risk mitigating measures. Casualty databases are today still the primary source of this information on accidents and incidents. Accident investigation reports provide more detailed information on the accident scenario and facilitating improved risk analysis. Casualty information by IMO GISIS, IHS Markit and LMIU for the period 1990–2020 and containerships of more than 999 GT had been re-analyzed and information categorized for allowing statistical analysis of causes. A taxonomy had been developed for the consistent categorization of information and used to present accident causes in a more structured way. Appropriate statistics regarding the main causes for major types considering collision, contact, grounding, fire, explosion and failure of machinery equipment are presented in this paper. Historical trends and quantitative casualty characteristics are reported.

I want to thank you for your September/October issue. While I've never really noticed a lack of women of colour in your magazine, seeing so many women who have the [...]

Marine aviation logistics is undergoing a vast change in order to solve the root problems of aviation logistics and ensure that Marine aviation units have the necessary logistics support wherever they are located. The transformation is required in order to respond to ever-increasing operational requirements.

This study aimed to determine the feasibility of using radioablation for arrhythmogenic a substrate modification.

Ventricular arrhythmias are the leading cause of sudden cardiac death. Current treatment strategies for ventricular tachycardia, including antiarrhythmic drugs and catheter ablation, have limited efficacy in patients with structural heart disease. Noninvasive ablation with the use of externally applied radiation (cardiac radioablation) has emerged as a promising and novel approach to treating recurrent ventricular tachycardias. However, the heart is generally an “organ at risk” for radiation treatments, such that very little is known on the effects of radiotherapy on cardiac ultrastructure and electrophysiologic properties. Furthermore, there has been limited interaction between the fields of cardiology and radiation oncology and physics. The advent of cardiac radioablation will undoubtedly increase interactions between cardiologists, cardiac electrophysiologists, radiation oncologists and physicists. There is an important knowledge gap separating these specialties, but scientific developments, technical optimisation, and improvements depend on intense multidisciplinary collaboration. This manuscript seeks to review the basic of radiation physics and biology for cardiovascular specialists in an effort to facilitate constructive scientific and clinical collaborations to improve patient outcomes.

Advances in artificial intelligence (AI) and medical imaging have opened new avenues for the diagnosis and management of prostate cancer. In particular, AI technology can enhance the performance of fusion magnetic resonance imaging–targeted biopsy of the prostate, and has the potential to enhance the usability and precision of this biopsy technique, guide treatment decisions, and further advance prostate cancer care.

Planetary roller screws combine efficiency and reliability to handle heavy loads at high speeds which make them ideal for rugged applications. Planetary roller screws have threaded screw shaft, nut and rollers that are designed to allow planetary roller motion. This feature eliminates the need for recirculation thus requiring fewer components and providing longer life. The primarily cause for planetary roller screw failure is misalignment., Planetary roller screws handle heavy loads and high speeds. Linear actuators come in many different designs, but for rugged applications planetary roller screws are often a best choice. They have [...]

The configurational instability of allenyl copper reagents is unveiled. An experimental study highlights the crucial role of Li+and of the reaction temperature in the control of the configurational stability of allenyl copper reagents. A judicious choice of the reaction conditions allows efficient dynamic kinetic resolution processes and gives a one-pot access to homopropargylic alcohols or amines bearing up to four contiguous defined stereogenic centers.

Double-chambered right ventricle (DCRV), a form of right ventricular outflow obstruction that sometimes accompanies a ventricular septal defect (VSD), is associated with superior and rightward displacement of the septal insertion of the moderator band. It was hypothesized that this superior displacement is present and identifiable by echocardiography in patients with VSD even before right ventricular outflow tract obstruction develops. Eight patients who had a previous echocardiographic study showing a VSD alone were echocardiographically diagnosed as having DCRV. Their initial echocardiographic studies were reviewed, and superior displacement of the moderator band was quantified by measuring the distance between the pulmonary valve and moderator band, normalized to tricuspid anulus diameter. These measurements were compared with those from the initial studies of the following 3 other groups: (1) an age-matched group of 10 patients with no structural heart disease; (2) an age-matched group of 10 patients with a VSD who did not develop DCRV; and (3) a group (not age-matched) of 10 patients with VSD and DCRV in whom subpulmonary obstruction was present on the initial study. The 8 patients who eventually developed subpulmonary obstruction had significant superior displacement of the moderator band at the time of their initial echocardiogram compared with that of the 2 age-matched control groups (p Superior displacement of the moderator band is quantifiable by 2-dimensional echocardiography and may help to predict which infants with a VSD are at risk to develop subpulomonary obstruction.

Recent advancements in the delivery of therapeutics for retinal diseases include the development of injectable hydrogels, networks of one or more hydrophilic polymers that contain a high-volume fraction of water. These systems are of particular interest due to their biocompatibility, permeability to water-soluble metabolites, and function as minimally invasive injectable delivery vehicles. Recently, hydrogels for ophthalmic applications have been developed that display a controlled release of factors necessary for cellular survival and proliferation. Understanding the relationship between the volume water fraction and the physical, chemical, and diffusion properties of the hydrogel scaffold could aid in the improvement of existing drug delivery treatments for retinal regeneration. In this study, we compared the diffusion and release of human epidermal growth factor (hEGF) encapsulated in different injectable homogenous and heterogenous hydrogels, namely gelatin-hydroxyphenyl propionic acid (Gtn-HPA) and hyaluronic acid-tyramine (HA-Tyr)-based hydrogels. These experimental results were compared with the measured stiffness and water content of these hydrogels and applied to different diffusion theories of polymers to determine the model of best fit. We find that the normalized diffusion and release of hEGF increases with free water content in injectable hydrogels: ranging from 0.176 at 41% free water in HA-Tyr to 0.2 at 53% free water in Gtn-HPA, whereas it decreases with hydrogel stiffness: 600 Pa for Gtn-HPA and 1440 Pa for HA-Tyr. Further, we compared our experimental data with theoretical diffusion models. We found that homogeneous theoretical models, notably the hydrodynamic model (giving a normalized diffusion close to 0.2), provide the most suitable explanation for the measured solute diffusion coefficient.Impact statementDiffusion in a three-dimensional system is a key factor in designing new hydrogel-based materials. It allows to control and predict diffusion in implants and delivery systems. However, very little is done to explore and test the diffusion since it is a complex process. Many models can predict solute diffusion; however, practical application using these models has not yet been done. We have shown the variation of these models in a practical extent, which could have a tremendous impact on designing biomaterial for biological application as it allows one to understand the diffusion of injected drugs and growth factors.

The advent of personalized medicine has driven the development of novel approaches for obtaining detailed cellular and molecular information from clinical tissue samples. Tissue cytometry is a promising new technique that can be used to enumerate and characterize each cell in a tissue and, unlike flow cytometry and other single-cell techniques, does so in the context of the intact tissue, preserving spatial information that is frequently crucial to understanding a cell's physiology, function, and behavior. However, the wide-scale adoption of tissue cytometry as a research tool has been limited by the fact that published examples utilize specialized techniques that are beyond the capabilities of most laboratories. Here we describe a complete and accessible pipeline, including methods of sample preparation, microscopy, image analysis, and data analysis for large-scale three-dimensional tissue cytometry of human kidney tissues. In this workflow, multiphoton microscopy of unlabeled tissue is first conducted to collect autofluorescence and second-harmonic images. The tissue is then labeled with eight fluorescent probes, and imaged using spectral confocal microscopy. The raw 16-channel images are spectrally deconvolved into 8-channel images, and analyzed using the Volumetric Tissue Exploration and Analysis (VTEA) software developed by our group. We applied this workflow to analyze millimeter-scale tissue samples obtained from human nephrectomies and from renal biopsies from individuals diagnosed with diabetic nephropathy, generating a quantitative census of tens of thousands of cells in each. Such analyses can provide useful insights that can be linked to the biology or pathology of kidney disease. The approach utilizes common laboratory techniques, is compatible with most commercially-available confocal microscope systems and all image and data analysis is conducted using the VTEA image analysis software, which is available as a plug-in for ImageJ.

This study sought to determine whether a novel impedance thermal imaging system (ITIS) provides an impedance measurement that is better correlated with lesion dimensions than circuit impedance during radiofrequency (RF) ablation.

Chronic kidney disease (CKD) and acute kidney injury (AKI) are common, heterogeneous, and morbid diseases. Mechanistic characterization of CKD and AKI in patients may facilitate a precision-medicine approach to prevention, diagnosis, and treatment. The Kidney Precision Medicine Project aims to ethically and safely obtain kidney biopsies from participants with CKD or AKI, create a reference kidney atlas, and characterize disease subgroups to stratify patients based on molecular features of disease, clinical characteristics, and associated outcomes. An additional aim is to identify critical cells, pathways, and targets for novel therapies and preventive strategies. This project is a multicenter prospective cohort study of adults with CKD or AKI who undergo a protocol kidney biopsy for research purposes. This investigation focuses on kidney diseases that are most prevalent and therefore substantially burden the public health, including CKD attributed to diabetes or hypertension and AKI attributed to ischemic and toxic injuries. Reference kidney tissues (for example, living-donor kidney biopsies) will also be evaluated. Traditional and digital pathology will be combined with transcriptomic, proteomic, and metabolomic analysis of the kidney tissue as well as deep clinical phenotyping for supervised and unsupervised subgroup analysis and systems biology analysis. Participants will be followed prospectively for 10 years to ascertain clinical outcomes. Cell types, locations, and functions will be characterized in health and disease in an open, searchable, online kidney tissue atlas. All data from the Kidney Precision Medicine Project will be made readily available for broad use by scientists, clinicians, and patients.

The use of kidney histopathology for predicting kidney failure is not established. We hypothesized that the use of histopathologic features of kidney biopsy specimens would improve prediction of clinical outcomes made using demographic and clinical variables alone.

This study sought to identify midmyocardial arrhythmogenic substrates by examining the frequency content of unipolar endocardial surface electrograms, comparing sites with transmural scar versus sites with intramural excitable substrate (IES) as identified during needle catheter ablation for ventricular tachycardia (VT).

Catheter ablation is an effective therapy for atrial fibrillation (AF). However, risks remain, and improved efficacy is desired. Stereotactic body radiotherapy (SBRT) is a well‐established therapy used to noninvasively treat malignancies and functional disorders with precision. We evaluated the feasibility of stereotactic radioablation for treating paroxysmal AF. Two patients with drug‐refractory paroxysmal AF underwent pulmonary vein isolation with SBRT. After placement of a percutaneous active fixation temporary pacing lead tracking fiducial, computed tomography (CT) angiography was performed to define left atrial anatomy. A tailored planning treatment volume was created to deliver contiguous linear ablations to isolate the pulmonary veins and posterior wall. Patients were treated on an outpatient basis in the radioablation suite. Clinical follow‐up was performed through at least 24 months after therapy. Both patients successfully underwent SBRT planning and treatment without significant early or long‐term side effects up to 48 months of follow‐up. One patient had AF recurrence after 6 months free of arrhythmia, while the second patient remains free of AF after 24 months with fibrosis detected on MRI scan consistent with the ablation lesion set. An incidentally noted small pericardial effusion occurred in one patient. Stereotactic radioablation may be feasible for the treatment of drug‐refractory AF. Further evaluation is warranted. We evaluated the feasibility of stereotactic radioablation for treating paroxysmal atrial fibrillation. Two patients with drug‐refractory paroxysmal atrial fibrillation underwent pulmonary vein isolation with SBRT and followed for more than 24 months; one patient remained free of AF, with MRI findings consistent with left atrial fibrosis at ablation sites. We conclude that it is feasible to apply radioablation to the treatment of AF and further evaluation is warranted.

Acute kidney injury (AKI) is an important contributor to the development of chronic kidney disease (CKD). There is a need to understand molecular mediators that drive recovery and progression to CKD. In particular, the regulatory role of miRNAs in AKI is poorly understood. miRNA and mRNA sequencing were performed on biobanked human kidney tissues obtained in the routine care of subjects with a diagnosis of AKI, minimal change disease (MCD), or without known kidney disease in nephrectomy (Ref) tissue. mRNA analysis revealed that Ref tissues exhibited an injury signature similar to AKI, and not identified in MCD samples. The transcriptomic signature of human AKI was enriched in pathways involved in cell adhesion, epithelial-to-mesenchymal transition, and cell cycle arrest (e.g., CDH6, ITGB6, CDKN1A). In AKI, upregulation of miR-146a, miR-155, miR-142, miR-122 was associated with pathways involved in immune cell recruitment, inflammation, and epithelial-to-mesenchymal transition. miR-122 and miR-146 are associated with downregulation of DDR2and IGFBP6, genes involved in recovery and progression of kidney disease. These data provide integrated miRNA signatures that complement mRNA and other epigenetic data available in kidney atlases.

Fluorescence lifetime imaging microscopy (FLIM) provides additional contrast for fluorophores with overlapping emission spectra. The phasor approach to FLIM greatly reduces the complexity of FLIM analysis and enables a useful image segmentation technique by selecting adjacent phasor points and labeling their corresponding pixels with different colors. This phasor labeling process, however, is empirical and could lead to biased results. In this Letter, we present a novel and unbiased approach to automate the phasor labeling process using an unsupervised machine learning technique, i.e., K-means clustering. In addition, we provide an open-source, user-friendly program that enables users to easily employ the proposed approach. We demonstrate successful image segmentation on 2D and 3D FLIM images of fixed cells and living animals acquired with two different FLIM systems. Finally, we evaluate how different parameters affect the segmentation result and provide a guideline for users to achieve optimal performance.

Grazing land models can assess the provisioning and trade-offs among ecosystem services attributable to grazing management strategies. We reviewed 12 grazing land models used for evaluating forage and animal (meat and milk) production, soil C sequestration, greenhouse gas emission, and nitrogen leaching, under both current and projected climate conditions. Given the spatial and temporal variability that characterizes most rangelands and pastures in which animal, plant, and soil interact, none of the models currently have the capability to simulate a full suite of ecosystem services provided by grazing lands at different spatial scales and across multiple locations. A large number of model applications have focused on topics such as environmental impacts of grazing land management and sustainability of ecosystems. Additional model components are needed to address the spatial and temporal dynamics of animal foraging behavior and interactions with biophysical and ecological processes on grazing lands and their impacts on animal performance. In addition to identified knowledge gaps in simulating biophysical processes in grazing land ecosystems, our review suggests further improvements that could increase adoption of these models as decision support tools. Grazing land models need to increase user-friendliness by utilizing available big data to minimize model parameterization so that multiple models can be used to reduce simulation uncertainty. Efforts need to reduce inconsistencies among grazing land models in simulated ecosystem services and grazing management effects by carefully examining the underlying biophysical and ecological processes and their interactions in each model. Learning experiences among modelers, experimentalists, and stakeholders need to be strengthened by co-developing modeling objectives, approaches, and interpretation of simulation results.

Details on a compact memory architecture aimed at high-performance, low-cost embedded DRAM for subquarter-micron generations will be presented at the Custom Integrated Circuits Conference this week. The following article contains […]

The dynamic interaction between swash and beach groundwater is fundamental to understanding wave runup and sediment transport processes. A numerical model that simultaneously resolves free surface and porous media flow for a variably saturated subsurface is presented. The novel numerical model, SedOlaFlow, is developed by merging the existing two‐phase, Eulerian sediment transport model, SedWaveFoam, with the surface wave solver, olaFlow. SedOlaFlow is validated with large wave flume surface and subsurface data for dam‐break driven swash over permeable gravel and sand beaches. Sediment size significantly impacts the swash‐groundwater relationship through infiltration/exfiltration and subsurface processes which modulate runup. Model results demonstrate that vertical infiltration into the upper unsaturated beach leads to a delayed groundwater table response to swash in the sand beach. Pressure fluctuations in the sand beach are not directly indicative of the swash depth or groundwater table and exfiltration may occur even when the swash depth is non‐zero. Groundwater circulation induced by a single swash event is non‐uniform and highly dynamic in the variably saturated vadose zone. Elevated ambient groundwater levels generally increase swash extent and duration. These findings establish the existence of a bi‐directional relationship between swash and groundwater flows and have significant implications on the effects of sea level rise on coastal flooding. In order to understand and accurately predict coastal hazards, it is crucial to study how waves and beach groundwater interact in the swash zone. The swash zone is the area of the beach that is intermittently covered and uncovered by waves. This region is highly complex and challenging to study with both surface flows (i.e., swash) and subsurface flows (i.e., beach groundwater) that are time‐varying, turbulent, and interconnected. Researchers have extensively investigated how surface flows affect beach groundwater and sediment mobility. However, the influence of beach groundwater on swash flow behaviors is not well understood. A numerical model (SedOlaFlow) was developed to study swash and beach groundwater interactions. Measurements from laboratory experiments conducted on gravel and sand beaches were used to validate SedOlaFlow. Swash and beach groundwater behavior are significantly influenced by beach sediment size and permeability (i.e., how easily fluid flows through sediment). Rapid pressure changes within the sand beach cause the beach groundwater table to rise. Swash that infiltrates through the beach creates complicated flow patterns within the sand beach. Model results show higher groundwater levels may increase the maximum distance and time waves travel on the beach. This has significant implications for understanding and managing coastal vulnerability. A novel numerical model (SedOlaFlow) that resolves free surface and porous media flow for a variably saturated subsurface is presentedSediment size and permeability effects on the swash–groundwater relationship and subsurface flow are isolated by model experimentsAmbient groundwater levels impact swash extent and duration, confirming a bi‐directional relationship between swash and groundwater flows A novel numerical model (SedOlaFlow) that resolves free surface and porous media flow for a variably saturated subsurface is presented Sediment size and permeability effects on the swash–groundwater relationship and subsurface flow are isolated by model experiments Ambient groundwater levels impact swash extent and duration, confirming a bi‐directional relationship between swash and groundwater flows

Kidney biopsy remains the gold standard for uncovering the pathogenesis of acute and chronic kidney diseases. However, the ability to perform high resolution, quantitative, molecular and cellular interrogation of this precious tissue is still at a developing stage compared to other fields such as oncology. Here, we discuss recent advances in performing large-scale, three-dimensional (3D), multi-fluorescence imaging of kidney biopsies and quantitative analysis referred to as 3D tissue cytometry. This approach allows the accurate measurement of specific cell types and their spatial distribution in a thick section spanning the entire length of the biopsy. By uncovering specific disease signatures, including rare occurrences, and linking them to the biology in situ, this approach will enhance our understanding of disease pathogenesis. Furthermore, by providing accurate quantitation of cellular events, 3D cytometry may improve the accuracy of prognosticating the clinical course and response to therapy. Therefore, large-scale 3D imaging and cytometry of kidney biopsy is poised to become a bridge towards personalized medicine for patients with kidney disease.

This article presents a systematic approach for assessing the maturity of manufacturing technologies. A methodology is proposed that is based on modelling the capability of the individual processes and technology interfaces between them. It is inspired by a capability maturity model which has been applied successfully in the field of software engineering. The methodology was developed to assess the maturity levels of individual processes and the combined maturity of pairs or chains of processes. To demonstrate its validity, it was applied for assessing the maturity of technologies in the micro and nano manufacturing domain. The results demonstrated its applicability as a tool for evaluating the maturity of micro and nano manufacturing pairs and their constituent processes. Also, it was shown that the methodology can be employed for identifying process pairs, suitable for integration in process chains, together with their potential weaknesses.