Our objective was to determine whether the chemoreflex from human muscle is elicited by small graded reductions in muscle blood flow (MBF) during mild exercise or whether this reflex has an obvious threshold associated with large changes in femoral venous lactate and H+ levels (i.e., as in dogs with high muscle oxidative capacity). Seven subjects exercised supine at 40, 87, and 142 W; lower body positive pressure (LBPP) was applied in 3-min steps at 25, 35, 45, and 50-60 mmHg with the lower body and the cycle ergometer in a sealed box. Estimated MBF (Fick) fell by 5.3 +/- 4.3 to 19.9 +/- 3.8% at four levels of LBPP over three work rates. Mean arterial pressure (MAP), heart rate (HR), and plasma norepinephrine (NE) concentration rose with increasing LBPP. MAP was significantly correlated with femoral venous pH, lactate, O2 tension, and O2 content during moderate and heavy exercise, without an apparent threshold. Percentage decreases in muscle vascular conductance exceeded the decreases in MBF twofold, indicating significant opposition to reduction in MBF by the chemoreflex. Approximately 50% of the correction of MBF back toward control (i.e., at 0 LBPP) could be explained by increased cardiac output, calculated from the rise in HR; the remaining correction could be attributed to both sympathetic vasoconstriction (indicated by high NE levels) and to mechanical effects of partial occlusion. Results suggest that in humans stepwise reductions in MBF gradually elicit muscle chemoreflexes with no apparent threshold at these levels of exercise.

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Of the build out of humanity predicted up to the end of the century, a substantial portion will occur within informal urban settlements – areas characterised by poor access to infrastructure and services. There is a pressing need to better understand how and with what implications the growing proliferation of Internet of Things (IoT) technologies, as a component of smart urbanism, are being applied to address the challenges of these areas. The following paper addresses this research gap, showing how IoT technology is reconfiguring trust within water and energy infrastructures in Nairobi. We apply work on informal urban infrastructures and smart urbanism to three case studies, producing novel insights into how IoT technologies reconfigure connections between users, providers and infrastructures. This reconfiguration of trust smooths chronic infrastructural uncertainties and generates reliability within informal settlements and, in doing so, leads to increased personal economies. We conclude by considering how these examples provide insights into the implications of IoT for everyday urbanisms in informal settlements and how these insights relate to global smart city debates more widely.

For many researchers, conducting fieldwork can often form a significant component of data collection. With a rich history across many disciplines, fieldwork has received significant reflexive examination, notably around when it is conducted in dangerous areas or used for researching high-risk situations. Less attended to, however, are the equally disruptive but less dangerous situations that researchers can face, such as conducting fieldwork during political turmoil. The aim of this paper is to explore the impact of political turmoil on fieldwork, and reflectively examine both the consequences of this and possible ways of mitigation. Through examining fieldwork notes and journals, the findings identified that despite political turmoil's significant disruption on processes of data collection, the researcher utilised notions of flexible positionalities and developed adaptive methodologies to circumvent these challenges. The paper provides new insights for managing the impact of disruption on fieldwork from political turmoil and encourages the continuation of publications focusing on reflective fieldwork accounts.