Comparison of different flowability tests for powders for inhalation

A series of placebo powders for inhalation was characterized regarding bulk density and powder flowability using different techniques. The powders were of the ordered mixture type and were prepared by mixing a pharmaceutical carrier grade of lactose with different fractions of intermediate sized and fine (i.e., micronized) lactose. A modified Hausner Ratio was obtained by measurement of the poured and the compressed bulk densities. Other tests investigated were the angle of repose, the avalanching behaviour using the AeroFlow, and the yield strength using the Uniaxial tester. Furthermore, the relation between ordered mixture composition and flowability was examined.Of the methods investigated, the modified Hausner Ratio discriminates well between the investigated powders and seems to have the widest measuring range. It was also found that the poured and compressed bulk densities provide information about the packing of the particles in the powders. A good correlation was obtained between the modified Hausner Ratio and the angle of repose. The AeroFlow was suitable for powders with a low percentage of fine particles, but could not discriminate between the more cohesive powders. The Uniaxial tester, on the other hand, seems to be better suited for more cohesive powders.Regarding the powder composition, addition of micronized particles has a strong influence on the flowability of ordered mixtures, while intermediate sized particles have little impact on the powder flow.     

Simplified cloud-oriented virtual machine management with MLN

System administrators are faced with the challenge of making their existing systems power-efficient and scalable. Although cloud computing is offered as a solution to this challenge by many, we argue that having multiple interfaces and cloud providers can result in more complexity than before. This paper addresses cloud computing from a user perspective. We show how complex scenarios, such as an on-demand render farm and scaling web-service, can be achieved utilizing clouds but at the same time keeping the same management interface as for local virtual machines. Further, we demonstrate that by enabling the virtual machine to have its policy locally instead of in the underlying framework, it can move between otherwise incompatible cloud providers and sites in order to achieve its goals more efficiently.     

Principle Components and Importance Ranking of Distributed Anomalies

Correlations between locally averaged host observations, at different times and places, hint at information about the associations between the hosts in a network. These smoothed, pseudo-continuous time-series imply relationships with entities in the wider environment. For anomaly detection, mining this information might provide a valuable source of observational experience for determining comparative anomalies or rejecting false anomalies. The difficulties with distributed analysis lie in collating the distributed data and in comparing observables on different hosts, in different frames of reference. In the present work, we examine two methods (Principle Component Analysis and Eigenvector Centrality) that shed light on the usefulness of comparing data destined for different locations in a network.     

Numerical modeling of adhesive particle mixing

The discrete element method is used to investigate adhesive particle mixing in a system that includes large carrier particles and fine particle agglomerates in a Couette mixer. The simulation starts with 200 carriers and 10 agglomerates with 1000 fine particles each. During mixing, the agglomerates are broken, fractions adhere to the carriers, and there is continuous redistribution of fines between carriers. The focus is to obtain information on the quantity and quality of fine particles adhered to carriers by postprocessing the simulation data. Variation in the structure of agglomerates due to shearing is studied over mixing time. Findings indicate that major fraction of fine particles are dispersed evenly onto the surface of carriers and the rest are in form of free debris. A time‐dependent index is introduced to predict the degree of mixing. Finally, the adhesion force between carriers and coated layers is observed to have a peak at 1 nN. © 2017 American Institute of Chemical Engineers AIChE J, 63: 2599–2609, 2017     

Gestalt descriptions embodiments and medical image interpretation

In this paper I will argue that medical specialists interpret and diagnose through technological mediations like X-ray and fMRI images, and by actualizing embodied skills tacitly they are determining the identity of objects in the perceptual field. The initial phase of human interpretation of visual objects takes place during the moments of visual perception before we are consciously aware of the perceived. What facilitate this innate ability to interpret are experiences, learning and training that become humanly embodied skills. These embodied skills are actualized during the moments of visual perception. My argument is that biology, society and instruments constitute unique individual ontologies influencing specialist readings of the technological output, in other words, putting limits on the “truth-to-nature” relation, which is so much sought for in science.     

A systematic review on the use of quantitative imaging to detect cancer therapy adverse effects in normal-appearing brain tissue

Cancer therapy for both central nervous system (CNS) and non-CNS tumors has been previously associated with transient and long-term cognitive deterioration, commonly referred to as ‘chemo fog’. This therapy-related damage to otherwise normal-appearing brain tissue is reported using post-mortem neuropathological analysis. Although the literature on monitoring therapy effects on structural magnetic resonance imaging (MRI) is well established, such macroscopic structural changes appear relatively late and irreversible. Early quantitative MRI biomarkers of therapy-induced damage would potentially permit taking these treatment side effects into account, paving the way towards a more personalized treatment planning.

This systematic review (PROSPERO number 224196) provides an overview of quantitative tomographic imaging methods, potentially identifying the adverse side effects of cancer therapy in normal-appearing brain tissue. Seventy studies were obtained from the MEDLINE and Web of Science databases. Studies reporting changes in normal-appearing brain tissue using MRI, PET, or SPECT quantitative biomarkers, related to radio-, chemo-, immuno-, or hormone therapy for any kind of solid, cystic, or liquid tumor were included. The main findings of the reviewed studies were summarized, providing also the risk of bias of each study assessed using a modified QUADAS-2 tool. For each imaging method, this review provides the methodological background, and the benefits and shortcomings of each method from the imaging perspective. Finally, a set of recommendations is proposed to support future research.

     

Digital assessment in higher education

Statistics show there is a clear relationship between higher education and employment in Norway, especially for people with disabilities. The use of digital assessment solutions is increasing in Norwegian higher education. The overall goal of this study is therefore to highlight the potential for improvement of current practices related to universal design, both for providers of digital assessment solutions and for higher education institutions. Based on a case study of practices in Norwegian higher education sector, this article reviews existing requirements for ensuring universal design in digital assessment solutions, prototypes an approach to evaluating universal design quality (UD-Q) of two major Norwegian digital assessment solutions and investigates the compliance between providers’ self-assessments from interviews and UD-Q evaluation scores. The article presents two contributions: (1) an improved set of requirements for universal usability when procuring digital assessments solutions and (2) UD-Q, a stepwise feature analysis-based expert inspection method for evaluating the UD-Q of digital assessment solutions.     

Simulation of dry powder inhalers: Combining micro‐scale,meso‐scale and macro‐scale modeling

The flow of carrier particles, coated with active drug particles, is studied in a prototype dry powder inhaler. A novel, multiscale approach consisting of a discrete element model (DEM) to describe the particles coupled with a dynamic large eddy simulation (LES) model to describe the dynamic nature of the flow is applied. The model consists of three different scales: the micro‐scale, the meso‐scale, and the macro‐scale. At the micro‐scale, the interactions of the small active drug particles with larger carrier particles, with the wall, with the air flow, and with each other is thoroughly studied using discrete element modeling and detailed computational fluid dynamics (CFD), i.e., resolving the flow structures around the particles. This has led to the development of coarse‐grained models, describing the interaction of the small active drug particles at the larger scales. At the meso‐scale the larger carrier particles, and all of their interactions are modeled individually using DEM and CFD‐LES. Collisions are modeled using a visco‐elastic model to describe the local deformation at each point of particle‐particle contact in conjunction with a model to account for cohesion. At the macro‐scale, simulations of a complete prototype inhaler are carried out. By combining the relevant information of each of the scales, simulations of the inhalation of one dose from a prototype inhaler using a patient relevant air flow profile show that fines leave the inhaler faster than the carrier particles. The results also show that collisions are not important for particle‐particle momentum exchange initially but become more important as the particles accelerate. It is shown that for the studied prototype inhaler the total release efficiency of the fine particles is between 10 and 30%, depending on the Hamaker constant, using typical settings for the properties of both particles. The results are also used to study regions of recirculation, where carrier particles can become trapped, and regions where fines adhere to the wall of the device. © 2016 American Institute of Chemical Engineers AIChE J, 63: 501–516, 2017     

On the usefulness of off-the-shelf computer peripherals for people with Parkinson’s Disease

People who suffer from Parkinson’s Disease face many challenges using computers, and mice are particularly problematic input devices. This article describes usability tests of standard peripherals for use by people with Parkinson’s Disease in order to identify optimal combinations with respect to the needs of this user group. The results are used to determine their effect upon inertia, muscle stiffness, tremor, pain, strain and coordination and show that widely available equipment could significantly improve mouse pointer control for many users. The results reflect the diversity of challenges experienced by computer users with Parkinson’s Disease, and also illustrate how projector-based technology may improve computer interaction without risking strain injuries.