The cells of the cardiovascular system can experience temperature excesses of a few degrees during a diseased state or of tens of degrees during a thermal therapy treatment. These raised temperatures may be acute or of long duration. The multiple cell lines that compose each tissue then react, in approximate order of increasing thermal insult, by expressing heat shock proteins, undergoing apoptosis, or suffering necrosis. Mathematical models of the response of cells could aid in planning and designing thermal therapies. The multifactor nature of the cell response makes it challenging to develop such models. The models most used clinically are mathematically simple and based on the response of representative tissues. The model that might provide the most fundamental understanding of the biochemical response of cells requires many parameters, some of which are difficult to measure. None of the semiempirical models that provide improved prediction of cell fate have been widely accepted to plan therapies. There remain great opportunities for developing mathematical models cell response.

The movement of macromolecules and nutrients in the brain is essential for brain health. Several neurological diseases are associated with the accumulation of amyloid beta or other waste products within the brain parenchyma. Alzheimer's disease, for example, is associated with elevated levels of amyloid beta peptides and tau proteins. Similarly, the brain tissue of patients with Parkinson's disease has a significant presence of Lewy bodies, another type of aggregated protein. The pathophysiology of these diseases includes elevated levels of cytokines and inflammasomes. Some have suggested that the increased production of cerebrospinal fluid during sleep might pass through the brain parenchyma and thereby clear such amyloid beta and misfolded proteins through the glymphatic pathway. While the brain is without common lymph vessels, subarachnoid lymphatic vessels have been (re)discovered and this strongly supports exchange of cerebral spinal fluid between the lateral ventricles and the lymph system to increase flow of the interstitial fluid through the brain parenchyma. The brain also possesses unusually selective capillaries that are supported by astrocyte foot processes. These unusual features lead to mass transport in the brain being an area of active research. This chapter offers a review of the mechanics of mass transport in the brain parenchyma with specific consideration of the amyloid beta and related species.

Cryolipolysis (CLL) is a noninvasive clinical procedure for local reduction of adipose tissue. Paddles as cold as -10 degrees C are pressed against the skin to cool the subcutaneous adipose tissue (SAT) to similar to 10 degrees C, crystalize the stored triglycerides, and trigger apoptosis in the adipocytes. Occasional adverse effects occur following CLL. There is some uncertainty in the temperature profile during the procedure. Here, a Green's function solution of the one-dimensional (1D) Pennes equation is used to examine how uncertainties in thermal diffusivity and blood perfusion may change the temperature profile during CLL. Improved description of the temperature profile might aid in understanding the mechanisms leading to these adverse effects. The plausible range of values of blood perfusion adds significant uncertainty to the temperature profile during treatment.

General thermomechanical analyses of elastomers require both thermoelastic and thermophysical properties over a whole range of temperatures and finite deformations. In this paper, a device is described that can measure three components of thermal diffusivity of elastomers that are subject to the biaxial loads, causing finite strains of up to 100 percent, and temperatures from 20 to 100°C. Data analysis is accomplished by a Marquardt parameter estimation using a finite difference solution of the diffusion equation. Reported here are preliminary measurements of the out-of-plane spatial thermal diffusivity in natural gum rubber specimens subjected to uniaxial and equal biaxial loading.

This review summarizes published findings of the beneficial and harmful effects on the heart, lungs, immune system, kidney, liver, and central nervous system of 47 drugs that have been proposed to treat COVID-19. Many of the repurposed drugs were chosen for their benefits to the pulmonary system, as well as immunosuppressive and anti-inflammatory effects. However, these drugs have mixed effects on the heart, liver, kidney, and central nervous system. Drug treatments are critical in the fight against COVID-19, along with vaccines and public health protocols. Drug treatments are particularly needed as variants of the SARS-Cov-2 virus emerge with some mutations that could diminish the efficacy of the vaccines. Patients with comorbidities are more likely to require hospitalization and greater interventions. The combination of treating severe COVID-19 symptoms in the presence of comorbidities underscores the importance of understanding the effects of potential COVID-19 treatments on other organs.

While much progress has been made in improving the performance of cavities in the past decade, reproducible performance remains elusive. This renewal of “The cost of grain boundaries on the performance of superconducting cavities” examines in further depth the interactions between forming and annealing processes and functional performance at the scale of dislocation substructure and grain boundaries. There are five tasks identified in the renewal, which are: Characterization / analysis of current cavity technology: Effect of deformation, heat treatment, surface treatments, and residual damage on cavity function (Lee and Bieler) Characterization of dislocation mechanisms in single and bicrystals (Bieler) Quantifying effects of impurities and deformation mechanisms in Nb using density functional theory calculations (Solanki) Crystal plasticity constitutive model development (Pourboghrat and Eisenlohr) Modeling and measuring thermal conductivity in thin layers (Wright)

The thermal conductivity k of superconducting tantalum (Ta) behaves similarly to that of superconducting niobium (Nb), albeit at colder temperatures. This shift is due to the superconducting transition temperature of Ta being 4.48 K, versus 9.25 K for Nb. For example, the temperature of the phonon peak of properly treated Ta is about 1 K as opposed to a phonon peak at about 2 K for Nb. The typical value of k of Ta is smaller than Nb with the value at the phonon peak for Ta being O(10) W m-1 K-1. Like Nb, k is dominated by phonons at these temperatures. This lattice k can be modeled by the Boltzmann transport equation, solved here by a Monte Carlo method using the relaxation time approximation. The phonon dispersion relation is included and some of the individual scattering mechanisms due to boundaries, dislocations, and residual normal electrons are examined. Differences in the thermal response of deformed Ta, as compared with Nb, may be attributed to differences in dislocation densities of the two metals following similar levels of deformation. Boundary scattering dominates at the coldest temperatures. The phonon peak decreases and shifts to warmer temperatures with increasing deformation.

The cells of the cardiovascular system can experience temperature excesses of a few degrees during a diseased state or of tens of degrees during a thermal therapy treatment. These raised temperatures may be acute or of long duration. The multiple cell lines that compose each tissue then react, in approximate order of increasing thermal insult, by expressing heat shock proteins, undergoing apoptosis, or suffering necrosis. Mathematical models of the response of cells could aid in planning and designing thermal therapies. The multi-factor nature of the cell response makes it challenging to develop such models. The models most used clinically are mathematically simple and based on the response of representative tissues. The model that might provide the most fundamental understanding of the biochemical response of cells requires many parameters, some of which are difficult to measure. None of the semi-empirical models that provide improved prediction of cell fate have been widely accepted to plan therapies. There remain great opportunities for developing mathematical models cell response.

The thermal conductivity of Niobium (Nb) often experiences a local maximum (a phonon peak) at a temperature between 1.8 and 3 K. While the magnitude of the phonon peak has been shown to be related to the dislocation density and may be influenced by manufacturing processes, little has been discussed as to the temperature at which the peak occurs. In examining these phenomena, it has been determined that more explicit accounting of phonon–dislocation scattering in a popular model better represents the thermal conductivity at temperatures colder than 3 K. Scaled sensitivity coefficients show this term to have similar influence as the phonon-electron and phonon-boundary scattering terms. Results using the enhanced model also show an apparent threshold of dislocation density (Nd < 1012 m−2) below which there is little contribution to the thermal conductivity of Nb.

The physical and mechanical metallurgy underlying fabrication of large grain cavities for superconducting radio frequency accelerators is summarized, based on research of 1) grain orientations in ingots, 2) a metallurgical assessment of processing a large grain single cell cavity and a tube, 3) assessment of slip behavior of single crystal tensile samples extracted from a high purity ingot slice before and after annealing at 800 degrees C / 2 h, 4) development of crystal plasticity models based upon the single crystal experiments, and 5) assessment of how thermal conductivity is affected by strain, heat treatment, and exposure to hydrogen. Because of the large grains, the plastic anisotropy of deformation is exaggerated, and heterogeneous strains and localized defects are present to a much greater degree than expected in polycrystalline material, making it highly desirable to computationally anticipate potential forming problems before manufacturing cavities.

The goal of the Materials Science SRF Cavity Group of Michigan State University and the National Superconducting Cyclotron has been (and continues to be) to understand quantitatively the effects of process history on functional properties. These relationships were assessed via studies on Nb samples and cavity parts, which had various combinations of forming processes, welding, heat treatments, and surface preparation. A primary focus was on large-grain cavity building strategies. Effects of processing operations and exposure to hydrogen on the thermal conductivity has been identified in single and bi-crystal samples, showing that the thermal conductivity can be altered by a factor of 5 depending on process history. Characterization of single crystal tensile samples show a strong effect of crystal orientation on deformation resistance and shape changes. Large grain half cells were examined to characterize defect content and surface damage effects, which provided quantitative information about the depth damage layers from forming.

Niobium is the current material of choice for the fabrication of superconducting radio frequency (SRF) cavities used in SRF based accelerators. Although niobium specifications for this application have been well established, material properties of as-received materials can still vary substantially. Required for the FRIB accelerator, $13.2M of niobium materials (sheet, tube, and flange) have been contracted to several niobium vendors. The FRIB cavity designs require very large niobium sheets, increasing the difficulty in fabrication and potential for contamination. FRIB has developed and initiated plans to control niobium specifications and perform incoming acceptance checks to ensure quality is maintained. Acceptance results from several niobium shipments will be presented, looking at several production lots from the same vendor and across multiple vendors. Non-conforming results were observed and will be discussed including follow-up investigations and mitigation strategies to improve quality of future shipments.