MapRecorder : analysing real-world usage of mobile map applications

This work was supported by Volkswagen Foundation [Lichtenbergprofessorship].Millions of people use mobile map applications like Google Maps on a regular basis. However, despite these applications' ubiquity, the literature contains very little information about how these applications are used in the real world. As such, many researchers and practitioners seeking to improve mobile map applications may not be able to identify important challenges and may miss major opportunities for innovation. To address this paucity of usage information, we collected and analysed data during unsupervised usage of Google Maps by replacing the standard application with a wrapped version called MapRecorder. In two studies we recorded data from locals and tourists using our application and collected over 580 minutes of actual application usage from 34 users, spanning 555 unique sessions. We identify typical usage scenarios, observe a large amount of map exploration and elucidate generalisable interaction patterns.Peer reviewe

Connective Memory Work on Justice for Mike Brown

This chapter addresses what I term the "connective memory work" carried out on Facebook page dedicated to achieving justice for Michael Brown, an African America teenager whose death at the gun of white police officer Darren Wilson in early August 2014 led to the Ferguson protests. The chapter outlines four types of connective memory work evident on the page. These types include the ‘memetic resurrection’ that involved the appropriation of iconic historical imagery alongside those of networked commemoration, digital archiving and curation, and crowd reconstruction. Central to this contribution the call to rethink the digital memory work practices of activists so as to integrate a concern for the agency of social media platforms themselves.<br/

Bacterial Toxicity of Potassium Tellurite: Unveiling an Ancient Enigma

Biochemical, genetic, enzymatic and molecular approaches were used to demonstrate, for the first time, that tellurite (TeO(3) (2−)) toxicity in E. coli involves superoxide formation. This radical is derived, at least in part, from enzymatic TeO(3) (2−) reduction. This conclusion is supported by the following observations made in K(2)TeO(3)-treated E. coli BW25113: i) induction of the ibpA gene encoding for the small heat shock protein IbpA, which has been associated with resistance to superoxide, ii) increase of cytoplasmic reactive oxygen species (ROS) as determined with ROS-specific probe 2′7′-dichlorodihydrofluorescein diacetate (H(2)DCFDA), iii) increase of carbonyl content in cellular proteins, iv) increase in the generation of thiobarbituric acid-reactive substances (TBARs), v) inactivation of oxidative stress-sensitive [Fe-S] enzymes such as aconitase, vi) increase of superoxide dismutase (SOD) activity, vii) increase of sodA, sodB and soxS mRNA transcription, and viii) generation of superoxide radical during in vitro enzymatic reduction of potassium tellurite

Catalases Are NAD(P)H-Dependent Tellurite Reductases

Reactive oxygen species damage intracellular targets and are implicated in cancer, genetic disease, mutagenesis, and aging. Catalases are among the key enzymatic defenses against one of the most physiologically abundant reactive oxygen species, hydrogen peroxide. The well-studied, heme-dependent catalases accelerate the rate of the dismutation of peroxide to molecular oxygen and water with near kinetic perfection. Many catalases also bind the cofactors NADPH and NADH tenaciously, but, surprisingly, NAD(P)H is not required for their dismutase activity. Although NAD(P)H protects bovine catalase against oxidative damage by its peroxide substrate, the catalytic role of the nicotinamide cofactor in the function of this enzyme has remained a biochemical mystery to date. Anions formed by heavy metal oxides are among the most highly reactive, natural oxidizing agents. Here, we show that a natural isolate of Staphylococcus epidermidis resistant to tellurite detoxifies this anion thanks to a novel activity of its catalase, and that a subset of both bacterial and mammalian catalases carry out the NAD(P)H-dependent reduction of soluble tellurite ion (TeO(3) (2−)) to the less toxic, insoluble metal, tellurium (Te°), in vitro. An Escherichia coli mutant defective in the KatG catalase/peroxidase is sensitive to tellurite, and expression of the S. epidermidis catalase gene in a heterologous E. coli host confers increased resistance to tellurite as well as to hydrogen peroxide in vivo, arguing that S. epidermidis catalase provides a physiological line of defense against both of these strong oxidizing agents. Kinetic studies reveal that bovine catalase reduces tellurite with a low Michaelis-Menten constant, a result suggesting that tellurite is among the natural substrates of this enzyme. The reduction of tellurite by bovine catalase occurs at the expense of producing the highly reactive superoxide radical

Deep Eutectic Solvents (DESs) and their applications [forthcoming]

Deep Eutectic Solvents (DESs) and Their Application

Virtual Patients and Sensitivity Analysis of the Guyton Model of Blood Pressure Regulation: Towards Individualized Models of Whole-Body Physiology

Mathematical models that integrate multi-scale physiological data can offer insight into physiological and pathophysiological function, and may eventually assist in individualized predictive medicine. We present a methodology for performing systematic analyses of multi-parameter interactions in such complex, multi-scale models. Human physiology models are often based on or inspired by Arthur Guyton's whole-body circulatory regulation model. Despite the significance of this model, it has not been the subject of a systematic and comprehensive sensitivity study. Therefore, we use this model as a case study for our methodology. Our analysis of the Guyton model reveals how the multitude of model parameters combine to affect the model dynamics, and how interesting combinations of parameters may be identified. It also includes a “virtual population” from which “virtual individuals” can be chosen, on the basis of exhibiting conditions similar to those of a real-world patient. This lays the groundwork for using the Guyton model for in silico exploration of pathophysiological states and treatment strategies. The results presented here illustrate several potential uses for the entire dataset of sensitivity results and the “virtual individuals” that we have generated, which are included in the supplementary material. More generally, the presented methodology is applicable to modern, more complex multi-scale physiological models

Revelations About Carotid Body Function Through its Pathological Role in Resistant Hypertension

Much recent attention has been given to the carotid body because of its potential role in cardiovascular disease states. One disease, neurogenic hypertension, characterised by excessive sympathetic activity, appears dependent on carotid body activity that may or may not be accompanied by sleep-disordered breathing. Herein, we review recent literature suggesting that the carotid body acquires tonicity in hypertension. We predict that carotid glomectomy will be a powerful way to temper excessive sympathetic discharge in diseases such as hypertension. We propose a model to explain that signalling from the ‘hypertensive’ carotid body is tonic, and hypothesise that there will be a sub-population of glomus cells that channel separately into reflex pathways controlling sympathetic motor outflows