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Vascular access for hemodialysis is the lifeline for patients with end-stage renal disease (ESRD); therefore, maintenance of the vascular access is of the utmost importance. The dialysis circuit can be complicated by stenosis or thrombosis. In particular, central venous stenosis is frequently encountered in the vascular access of patients with ESRD, and this complication may require endovascular management. Conventional catheter-based venography may be inadequate for identifying dynamic forms of extrinsic compression and intravascular webs associated with these lesions. For these types of access complications, balloon angioplasty remains the first-line intervention, with stenting reserved for selected scenarios. Accurate assessment of the venous configuration is therefore important to ensure an adequate treatment response. Intravascular ultrasound (IVUS) has been shown to be beneficial in lower extremity venous interventions. The use of IVUS in dialysis access interventions is currently limited but may be indicated in selected challenging clinical situations. In this article, we discuss the potential uses of IVUS in the ESRD population based on our institutional experience and on the current literature.

IMPORTANCE: The youth mental health crisis is exacerbated for Latinx adolescents, a group whose families are targets of anti-immigrant rhetoric and policy. OBJECTIVE: To investigate how immigration-related stressors are associated with disruptions in parent-child relationships and, in turn, the mental health symptoms of Latinx adolescents. DESIGN, SETTING, AND PARTICIPANTS: Data for this prospective cohort study of adolescent-mother dyads were derived from surveys completed at 3 time points spanning 4 years (time 1 [T1] in 2018, time 2 [T2] in 2020, and time 3 [T3] in 2022). Mediation analyses estimated paths from immigration-related stressors to parent-child relationship qualities to mental health symptoms from early to late adolescence. Multivariable and multivariate linear models within a structural equation modeling framework regressed mediators and outcome variables on their own T1 values, offering a scientifically rigorous test of mediation. The setting was a school district in suburban Atlanta, Georgia, and included Latinx adolescents (ages 11-16 years) randomly selected from grade and gender strata. Data were analyzed from June 2023 to March 2024. EXPOSURES: The primary independent variables were T1 mother reports of anti-immigrant worry and behavioral modification and adolescent reports of family member detention or deportation. Mediating variables were the reports of parental support and parent-child conflict of T2 adolescents. MAIN OUTCOMES AND MEASURES: T3 adolescent reports of past 6-month internalizing and externalizing symptoms. RESULTS: A total of 547 Latinx adolescents (mean [SD] age, 13.3 [1.0] years; 303 female [55.4%]; 244 male [44.6%]) were included in this study. Response rates were 65.2% (547 of 839) among contacted parents and 95.3% (547 of 574) among contacted adolescents with parental permission. Four-year retention rates were 67% (366 of 547 adolescents) and 65% (177 of 271 mothers). Structural model results showed that T1 anti-immigrant worry and behavioral modification was associated with T3 increases in externalizing symptoms indirectly through T1 to T2 increases in parent-child conflict (β = 0.03; SE = 0.02; 95% CI, 0-0.08). For girls, T1 family member deportation or detention was associated with T1 to T3 increases in internalizing and externalizing symptoms indirectly through T1 to T2 declines in parental support (internalizing: β = 0.04; SE = 0.02; 95% CI, 0-0.08; externalizing: β = 0.03; SE = 0.02; 95% CI, 0-0.07). Sensitivity analyses supported structural model findings. CONCLUSION AND RELEVANCE: Results of this cohort study suggest that legislative bodies, the health care system, and educational institutions should implement safeguards to mitigate potential harm conferred by anti-immigrant environments for parent-child relationships and, in turn, Latinx adolescents’ mental health.

Chemical ionization (CI) atmospheric pressure interface mass spectrometry is a unique analytical technique for its low detection limits, softness to preserve molecular information, and selectivity for particular classes of species. Here, we present a fast polarity switching approach for highly sensitive online analysis of a wide range of trace species in complex samples using selective CI chemistries and high-resolution mass spectrometry. It is achieved by successfully coupling a multischeme chemical ionization inlet (MION) and an Orbitrap Fourier transform mass spectrometer. The capability to flexibly combine ionization chemistries from both polarities effectively extends the detectability compared to using only one ionization chemistry, as commonly used positive and negative reagent ions tend to be sensitive to different classes of species. We tested the performance of the MION-Orbitrap using reactive gaseous organic species generated by α-pinene ozonolysis in an environmental chamber and a standard mixture of 71 pesticides. Diethylammonium and nitrate are used as reagent ions in positive and negative polarities. We show that with a mass resolving power of 280,000, the MION-Orbitrap can switch and measure both polarities within 1 min, which is sufficiently fast and stable to follow the temporal evolution of reactive organic species and the thermal desorption profile of pesticides. We detected 23 of the 71 pesticides in the mixture using only nitrate as the reagent ion. Facilitated by polarity switching, we also detected 47 pesticides using diethylammonium, improving the total number of detected species to 59. For reactive organic species generated by α-pinene ozonolysis, we show that combining diethylammonium and nitrate addresses the need to measure oxygenated molecules in atmospheric environments with a wide range of oxidation states. These results indicate that the polarity switching MION-Orbitrap can promisingly serve as a versatile tool for the nontargeted chemical analysis of trace species in various applications.

Abstract.Ultrasound has been established as an important diagnostic tool in assessing vascular abnormalities. Standard B-mode and Doppler techniques have inherent limitations with regards to detection of slow flow and small vasculature. Contrast-enhanced ultrasound (CEUS) is a complementary tool and is useful in assessing both the macro- and microvascular anatomy of the aorta. CEUS can also provide valuable physiological information in real-time scanning sessions due to the physical and safety profiles of the administered microbubbles. From a macrovascular perspective, CEUS has been used to characterize aortic aneurysm rupture, dissection and endoleaks post-EVAR repair. With regard to microvasculature CEUS enables imaging of adventitial vasa vasorum thereby assessing aortic inflammation processes, such as monitoring treatment response in chronic periaortitis. CEUS may have additional clinical utility since adventitial vasa vasorum has important implications in the pathogenesis of aortic diseases. In recent years, there have been an increasing number of studies comparing CEUS to cross-sectional imaging for aortic applications. For endoleak surveillance CEUS has been shown to be equal or in certain cases superior in comparison to CT angiography. The recent advancement of CEUS software along with the ongoing development of drug-eluting contrast microbubbles has allowed improved targeted detection and real-time ultrasound guided therapy for aortic vasa vasorum inflammation and neovascularization in animal models. Therefore, CEUS is uniquely suited to comprehensively assess and potentially treat aortic vascular diseases in the future.

Ultrasound (US) remains a valuable modality for the assessment of vascular diseases, with conventional sonographic techniques such as grayscale and Doppler US used extensively to assess carotid atherosclerosis and abdominal aortic aneurysms. However, conventional US techniques are inherently limited by factors such as operator dependency and limited field of view. There is an increasing interest in the use of advanced sonographic techniques such as contrast-enhanced US (CEUS) and 3-dimensional (3D) US to mitigate some of these limitations. Clinical applications of advanced sonographic techniques include surveillance of abdominal aortic aneurysm, post-endovascular aortic repair, and carotid atherosclerotic plaques. Recently published studies have demonstrated that CEUS and 3D US are superior to conventional US and comparable to computed tomography for certain vascular applications. Further research is required to fully validate the application of advanced sonographic techniques in evaluating various atherosclerotic diseases.

The Asmari reservoir in Haftkel field is one of the most prolific naturally fractured reservoirs in the Zagros folded zone in the southwest of Iran. The primary production was commenced in 1928 and continued until 1976 with a plateau rate of 200,000 bbl/day for several years. There was an initial gas cap on the oil column. Gas injection was commenced in June 1976 and so far, 28% of the initial oil in place have been recovered. As far as we concerned, fracture network is a key factor in sustaining oil production; therefore, it needs to be characterized and results be deployed in designing new wells to sustain future production. Multidisciplinary fracture evaluation from well to reservoir scale is a great privilege to improve model’s accuracy as well as enhancing reliability of future development plan in an efficient manner. Fracture identification and modeling usually establish at well scale and translate to reservoir using analytical or numerical algorithms with the limited tie-points between wells. Evaluating fracture network from production data can significantly improve conventional workflow where limited inter-well information is available. By incorporating those evidences, the fracture modeling workflow can be optimized further where lateral and vertical connectivity is a concern. This paper begins with the fracture characterization whereby all available data are evaluated to determine fracture patterns and extension of fracture network across the field. As results, a consistent correlation is obtained between the temperature gradient and productivity of wells, also convection phenomenon is confirmed. The findings of this section help us in better understanding fracture network, hydrodynamic communication and variation of temperature. Fracture modeling is the next step where characteristics of fractures are determined according to the structural geology and stress directions. Also, the fault’s related fractures and density of fractures are determined. Meanwhile, the results of data evaluation are deployed into the fracture model to control distribution and characteristics of fracture network, thereby a better representation is obtained that can be used for evaluating production data and optimizing development plan.

In this study, nanoemulsions (NEs) of Trachyspermum copticum(TCEO-NE), Mentha pulegium(MPEO-NE) and Satureja hortensis(SHEO-NE) essential oils were formulated and characterized. Their chemical composition was analyzed by gas chromatography/mass spectrometry. The NEs were formulated by ultrasound method using 15% EO (w/w), 80% water (w/w) and 5% surfactant (w/w). The droplet size, zeta potential, polydispersity index (PDI) and surface tension were measured. The NEs were characterized by ATR-FTIR. Their antimicrobial activity against four food-borne pathogens and their antioxidant effect were examined by DDPH and FRAP assays. MPEO-NE showed the smallest droplet size (125.40 nm) and the lowest PDI (0.37). The count of S. aureusdecreased from 6.52 to 3.54 log cfu/ml after 2 h likely due to the presence of pulegone, germacrene D and isopulegone in M. pulegiumEO while TCEO-NE had the most desirable IC50 value measured by FRAP test and 82.47% inhibitory activity against DPPH at concentration of 3 μg/ml. This high antioxidant activity could be attributed to thymol, limonene and α-terpinene in T. copticumEO. The results revealed that TCEO-NE and MPEO-NE could be incorporated into the food packaging materials to increase the shelf life of foods because of their favorable properties, antimicrobial and antioxidant activities. Therefore, they can be considered as natural alternatives for synthetic preservatives, however, some investigations are necessary to evaluate their use in food, potential health risks, and consumer acceptance.

ObjectiveTo improve the quality and participation in pediatric rheumatology research, patient-prioritized studies should be emphasized. We collaborated with United States–based pediatric rheumatology advocacy organizations to survey patients and caregivers of children with rheumatic diseases to identify what research topics were most important to them.MethodsWe conducted Web-based surveys and focus groups (FG) of patients and caregivers of children with juvenile myositis (JM), juvenile arthritis (JA), and childhood-onset systemic lupus erythematosus (cSLE). Surveys were emailed to listservs and posted to social media sites of JM, JA, and cSLE patient advocacy organizations. An initial survey asked open-ended questions about patient/caregiver research preferences. Responses were further characterized through FG. A final ranking survey asked respondents to rank from a list of research themes the 7 most important to them.ResultsThere were 365 JM respondents, 44 JA respondents, and 32 cSLE respondents to the final ranking survey. The top research priority for JM was finding new treatments, and for JA and cSLE, the priority was understanding genetic/environmental etiology. The 3 prioritized research themes common across all disease groups were medication side effects, disease flare, and disease etiology.ConclusionPatient-centered research prioritization is recognized as valuable in conducting high-quality research, yet there is a paucity of data describing patient/family preferences, especially in pediatrics. We used multimodal methodologies to assess current patient/caregiver research priorities to help frame the agenda for the pediatric rheumatology research community. Patients and caregivers from all surveyed disease groups prioritized the study of medication side effects, disease flares, and disease etiology.

Since its introduction, contrast‐enhanced ultrasound (CEUS) has gained an important role in the diagnosis and management of abdominal and pelvic diseases. Contrast‐enhanced ultrasound can improve lesion detection rates as well as success rates of interventional procedures when compared to conventional ultrasound alone. Additionally, CEUS enables the interventionalist to assess the dynamic enhancement of different tissues and lesions, without the adverse effects of contrast‐enhanced computed tomography, such as exposure to ionizing radiation and nephrotoxicity from iodinated contrast material. This review article describes the various applications and advantages of the use of CEUS to enhance performance of ultrasound‐guided interventions in the abdomen and pelvis.

In this report, design and assembly of a simple, easy-to-make and low-cost piezoelectric actuator (PZA) with one degree of freedom for application in phase-shifting interferometry is described. The PZA is designed in a way that its components can easily be manufactured and assembled. In the developed PZA, a series of ring-shaped piezo-ceramics are assembled inside a stainless steel case and through a couple of plate springs are preloaded. Planar electrodes are cut from a thin beryllium copper plate using wire-cut EDM and used on top and bottom sides of each ceramic plate. The supply voltage is applied to the electrodes by a designed control electronic circuit connected directly to a computer through a standard parallel port. A graphical user interface is developed in the MATLAB environment for controlling the converter. The electromechanical response of the PZA is studied by applying a calibration procedure based on using a Michelson interferometer. It is shown that by increasing the DC voltage from 0 to 200 V, the PZA has a good linear response. By using the PZA for strain field measurement in a rectangular steel plate, it is shown that the linear response of the designed PZA makes it a suitable candidate for use in Carré phase-shifting interferometry.

Introduction The term “carotidynia” has been used to describe a symptom or a nosologic entity characterized by pain in the lateral neck region and over the carotid bifurcation. Recent advances in diagnostic imaging and the introduction of diagnostic criteria have led to the adoption of term “Transient perivascular inflammation of the carotid artery” (TIPIC) syndrome.Method A retrospective analysis of the Radiology Department’s database was performed to identify cases with the diagnosis of TIPIC syndrome. The purpose was to identify ultrasound images including B-mode technique, colour, power Doppler technique and contrast-enhanced ultrasound (CEUS).Findings In total, five patients with the diagnosis of TIPIC syndrome are presented in this review. TIPIC syndrome is a clinic-radiologic entity characterized by pain over the carotid area, a symptom referring to a wide differential diagnosis where imaging plays a crucial role for proper diagnosis and treatment. Characteristic imaging findings on conventional ultrasound and CEUS are presented in this review.Discussion TIPIC syndrome can be investigated with virtually any imaging modality. Ultrasound typically reveals perivascular infiltration and a hypoechoic intimal plaque, while no significant luminal narrowing is appreciated. Computed tomography angiography and magnetic resonance angiography also demonstrate these vascular wall changes primarily affecting the distal common carotid artery, the carotid bulb and possibly the internal carotid artery proximal part. Contrast enhancement is a very characteristic and constant finding of TIPIC lesions, suggestive of the inflammatory nature of the disease and can be appreciated on computed tomography angiography and magnetic resonance angiography. CEUS has been recently used and successfully observed contrast enhancement of the lesions, similar to computed tomography angiography and magnetic resonance angiography.Conclusion Ultrasound remains the first-line modality for the evaluation of TIPIC syndrome, capable of providing all the information needed, especially if supplemented with the administration of microbubbles so that the enhancement of lesions can be evaluated.

A large prospective multicentre cohort study with systematic follow-up recently reported a 2.3% two-year cumulative incidence of chronic thromboembolic pulmonary hypertension (CTEPH) after acute pulmonary embolism (PE). The present investigation aimed to determine the reported prevalence and incidence of CTEPH diagnosis after acute PE in real-world practice over a twelve-year period.

To evaluate the benefits of arterial phase imaging and parenchymal blood volume (PBV) maps acquired by C-arm computed tomography during TACE procedure in comparison to cross-sectional imaging (CSI) using CT or MRI. From January 2014 to December 2016, a total of 29 patients with HCC stage A or B (mean age 65 years; range 47 to 81 years, 86% male) were included in this study. These patients were referred to our department for TACE treatment and received peri-interventional C-arm CT. Dual phase findings of each lesion in terms of overall image quality, conspicuity, tumor size and feeding arteries were compared between arterial phase imaging and PBV using 5-point semi-quantitative Likert-scale, whereby pre-interventional CSI served as reference standard. A significantly higher overall image quality of the PBV maps compared to arterial phase C-arm CT acquisitions (4.34 (±0.55) vs. 3.93 (±0.59), p= 0.0032) as well as a higher conspicuity of HCC lesions (4.27 ± 0.74 vs. 3.83 ± 1.08, p< 0.0001) was observed. Arterial phase imaging led to an overestimation of tumor size (mean size, 26.5 ± 15.9 mm) compared to PBV (24.9 ± 15.2 mm, p= 0.0004) as well as CSI (25.2 ± 15.1 mm), p= 0.021). Regarding detectability of tumor feeding arterial vessels, significantly more feeding vessels were detected in arterial phase C-arm CT (n= 1.67 ± 0.92 vessels) compared to PBV maps (n= 1.27 ± 0.63 vessels) (p= 0.0001). One lesion was missed in pre-interventional CT imaging, but detected by C-arm CT. The combination of PBV maps and arterial phase images acquired by C-arm CT during TACE procedure enables precise detection of the majority of HCC lesions and tumor feeding arteries and has therefore the potential to improve patient outcome.

Partial circulatory support is a promising concept for the treatment of heart failure patients. A better understanding of induced hemodynamic changes is essential for optimizing treatment efficacy. Computational fluid dynamics (CFD) is an alternative method to gain insight into flow phenomena difficult to obtain in vivo. In 10 patients implanted with a Circulite Synergy Micro-pump (HeartWare, Framingham, Massachusetts) (a continuous flow partial circulatory assist device connecting the left atrium to the right subclavian artery), transient CFD simulations were performed. Patients were divided into two groups depending on their cardiac output (CO; high CO group: 5.5 ± 1.1 L/min, low CO group: 1.7 ± 0.7 L/min). The partial assist device provided a supporting flow of 1.5 ± 0.8 L/min. Support was highest at diastole and decreased during systole because of a collision of the blood flows from the partial assist device and the CO. Reversed flow counteracting the flow of the device was significantly higher for the high CO group (mean flow in peak systole: −2.18 ± 1.08 vs.0.23 ± 0.59 L/min; p= 0.002) showing an inverse correlation between CO and amount of reversed flow during peak systole (R= −0.7; p< 0.02). The flow collision lead to higher total pressures at the point of collision and consequently in the Circulite outflow graft. The CFD simulations allow quantifying hemodynamic alterations in patients with partial support consisting of a flow collision, thereby reducing effectiveness of the circulatory support. Partial support in heart failure patients alternates their hemodynamics not only in providing support for the circulation but also inducing unfavorable changes in flow patterns.

Abstract.The pulmonary arteries are affected by a variety of congenital and acquired abnormalities. Multiple state-of-the art imaging modalities are available to evaluate these pulmonary arterial abnormalities, including computed tomography (CT), magnetic resonance imaging (MRI), echocardiography, nuclear medicine imaging and catheter pulmonary angiography. In part one of this two-part series on state-of-the art pulmonary arterial imaging, we review these imaging modalities, focusing particularly on CT and MRI. We also review the utility of these imaging modalities in the evaluation of pulmonary thromboembolism.

Abstract.Although pulmonary embolism is the most common abnormality of the pulmonary artery, there is a broad spectrum of other congenital and acquired pulmonary arterial abnormalities. Multiple imaging modalities are now available to evaluate these abnormalities of the pulmonary arteries. CT and MRI are the most commonly used cross-sectional imaging modalities that provide comprehensive information on several aspects of these abnormalities, including morphology, function, risk-stratification and therapy-monitoring. In this article, we review the role of state-of-the-art pulmonary arterial imaging in the evaluation of non-thromboembolic disorders of pulmonary artery.

This paper presents a study on the development of a side buffer to absorb the impact energy of colliding railcars. Buffers are essential elements for improving the traveling comfort of passengers and extending the service life of a wagon chassis. In designing the buffer’s energy absorption characteristics, a combination of a hydraulic damper and a stack of disc springs (Belleville springs) were utilized. Disc springs have nonlinear load–deflection characteristics; by stacking them in series and parallel arrangements, the desired load–deflection characteristics can be achieved. The finite element method was employed to evaluate the performance of the designed buffer in terms of force–stroke and kinetic, strain, and viscous energies for 5, 7, and 9 km/h impact velocities. Simulation results proved that the designed buffer ensures the requirements of EN 15551 easily for various collision speeds. Low level of acceleration values and small peak collision forces proved that the proposed buffer has superior performance in comparison with the existing buffers in service by improving the shock absorption and crashworthiness features of railcars.

Recurrent neural networks (RNN) are the backbone of many text and speech applications. These architectures are typically made up of several computationally complex components such as; non-linear activation functions, normalization, bi-directional dependence and attention. In order to maintain good accuracy, these components are frequently run using full-precision floating-point computation, making them slow, inefficient and difficult to deploy on edge devices. In addition, the complex nature of these operations makes them challenging to quantize using standard quantization methods without a significant performance drop. We present a quantization-aware training method for obtaining a highly accurate integer-only recurrent neural network (iRNN). Our approach supports layer normalization, attention, and an adaptive piecewise linear (PWL) approximation of activation functions, to serve a wide range of state-of-the-art RNNs. The proposed method enables RNN-based language models to run on edge devices with 2×improvement in runtime, and 4×reduction in model size while maintaining similar accuracy as its full-precision counterpart.

With the advent of deep learning applications on edge devices, researchers actively try to optimize deep learning model deployment on low-power and restricted memory devices. There are established compression methods such as quantization, pruning, and architecture search that leverage commodity hardware. Apart from conventional compression algorithms, one may redesign the operations of deep learning models, leading to more efficient hardware implementation. To this end, we propose EuclidNet, an efficient computing method designed to be implemented on hardware that replaces multiplication, with squared difference. We show that EuclidNet is aligned with matrix multiplication and can be used as a measure of similarity in the case of convolutional layers. Furthermore, we show that under various transformations and noise scenarios, EuclidNet exhibits the same performance compared to the deep learning models designed with multiplication operations.