Challenges of long-term vascular access in pediatric hemodialysis: Recommendations for practitioners

Kidney transplantation is the preferred treatment of end-stage renal disease in children. However, time to transplant varies, making a well-functioning long-term vascular access essential for performing hemodialysis efficiently and without disruption until a kidney becomes available. However, establishing long-term vascular access in pediatric patients can present distinct challenges due to this population's unique characteristics, such as smaller body size and lower-diameter blood vessels. There are three main pediatric long-term vascular access options, which include central venous catheters (CVC), arteriovenous fistula (AVF), and arteriovenous graft (AVG). CVC are currently the most widely used modality, although various studies and guidelines recommend AVF or AVG as the preferred option. Although AVF should be used whenever possible, it is crucial that clinicians consider factors such as patient size, physical exam findings, comorbidities, predicted duration of treatment to decide on the most optimal long-term vascular access modality. This article reviews the three long-term vascular access methods in children and the benefits and complications of each.     

Efficient online cycle detection technique combining with Steensgaard points‐to information

Pointer analysis is a key static analysis during compilation. Several client analyses and transformations rely on precise pointer information to optimize programs. Therefore, it is paramount to improve the efficiency of pointer analysis. A critical piece of an inclusion‐based pointer analysis is online cycle detection. The efficiency of pointer analysis is significantly influenced by the efficacy of detecting cycles. Existing approaches perform poorly when they guess cycle formation in the constraint graph. Thus, the number of false cycle‐detection triggers of the state‐of‐the‐art methods is considerably high (over 99% on Standard Performance Evaluation Corporation (SPEC) benchmarks). In this paper, we propose bootstrapping as a way to improve cycle detection predictability of pointer analysis. The main idea is to run a sequence of increasingly precise analyses to feed into the next more precise analysis to improve the efficiency of the latter analysis. In this process, we develop a new notion of pointer equivalence called constraint equivalence. Using Steensgaard's fast unification algorithm as the bootstrap, we devise a new cycle detection method for Andersen's inclusion‐based analysis. We measure the effectiveness of our approach using a suite of programs including SPEC 2000 benchmarks and two open‐source programs, and find that our method can reduce the number of false cycle detections by almost 22× compared with a state‐of‐the‐art method. This leads to an overall analysis time improvement of 18% on an average. Copyright © 2015 John Wiley & Sons, Ltd.     

A lithium poly(pyromellitic acid borate) gel electrolyte membrane for lithium-ion batteries

Lithium poly(pyromellitic acid borate) (PPAB) was synthesized via polymerization of lithium tetramethanolatoborate and silylated pyromellitic acid. The synthesized material was characterized by Fourier transformation infrared spectroscopy, ¹¹B nuclear magnetic resonance, scanning electron microscopy, and thermogravimetric analysis. And electrochemical characterizations were carried out on the blended PPAB/PVDF-HFP membrane. The PPAB-based composite membrane exhibits high lithium ionic conductivity, a broad electrochemical window and a high lithium-ion transference number. The battery cells assembled with the PPAB/PVDF-HFP/EC:PC composite membrane as the electrolyte perform reasonably well not only at elevated temperature but also at room temperature with good cyclability and discharge capacity, making the material suitable for applications in lithium-ion batteries.     

Automatic recognition of machining features from a solid model using the 2D feature pattern

Feature recognition systems are now widely identified as a cornerstone for conceiving an automated process planning system. Various techniques have been reported in the literature, but a few of them acquired a status of generic methodology. A flexible and robust approach is demanded for recognising a wide variety of features, e.g., non-interacting, interacting circular and slanting features. This research aims to exploit the concept of the ray - firing technique, in which a 2D surface pattern for each feature is generated and information is extracted from these patterns to correlate it with the corresponding machining features. The system first defines a virtual surface and then probing rays are dropped from each point of this surface to the 2.5D features of the B-rep solid model. According to the length of rays between the bottom face of the 2.5D machining features and the virtual surface, 2D feature patterns are formed for each machining feature. Finally, features are recognised using an algorithm described in this article. Different types of examples have been considered to demonstrate the effectiveness of the proposed approach.     

Analysis of Radiative Transport in a 2-D Cylindrical Participating Medium Subjected to Collimated Radiation

This article deals with the numerical analysis of radiative transport in a 2-D axisymmetric cylindrical enclosure containing absorbing, emitting, and scattering medium. The participating medium receives collimated radiation from the top boundary of the enclosure. Attenuation of the collimated radiation in the medium gives rise to the diffuse radiation. Thus, the governing radiative transfer equation accounts for both collimated and diffuse radiation. The radiative transfer equation is solved using the modified discrete ordinate method. Effects of extinction coefficient, scattering albedo, and aspect ratio on radial and axial distributions of heat flux and incident radiation are studied. In all cases, results are validated against those available in the literature. Modified discrete ordinate method has been found to provide accurate results.     

The MEK5/ERK5 Pathway in Health and Disease

The MEK5/ERK5 mitogen-activated protein kinases (MAPK) cascade is a unique signaling module activated by both mitogens and stress stimuli, including cytokines, fluid shear stress, high osmolarity, and oxidative stress. Physiologically, it is mainly known as a mechanoreceptive pathway in the endothelium, where it transduces the various vasoprotective effects of laminar blood flow. However, it also maintains integrity in other tissues exposed to mechanical stress, including bone, cartilage, and muscle, where it exerts a key function as a survival and differentiation pathway. Beyond its diverse physiological roles, the MEK5/ERK5 pathway has also been implicated in various diseases, including cancer, where it has recently emerged as a major escape route, sustaining tumor cell survival and proliferation under drug stress. In addition, MEK5/ERK5 dysfunction may foster cardiovascular diseases such as atherosclerosis. Here, we highlight the importance of the MEK5/ERK5 pathway in health and disease, focusing on its role as a protective cascade in mechanical stress-exposed healthy tissues and its function as a therapy resistance pathway in cancers. We discuss the perspective of targeting this cascade for cancer treatment and weigh its chances and potential risks when considering its emerging role as a protective stress response pathway.     

Two-dimensional single-crystalline Zn hexagonal nanoplates: size-controllable synthesis and X-ray diffraction study

We synthesized two-dimensional (2D) Zn hexagonal nanoplates using the thermal metal-vapor deposition technique. An increase and decrease in the surface area and thickness of the 2D Zn hexagonal nanoplates were shown with elevated annealing temperatures, indicating their sizes to be controlled using the annealing treatment. X-Ray diffractometry (XRD) studies revealed the crystalline nature of the 2D Zn hexagonal nanoplates and the diffraction intensity of the (002) lattice plane, which increased parabolically with elevated annealing temperatures.