Bringing Scheme programming to the iPhone—Experience

The iPhone SDK provides a powerful platform for the development of applications that make use of iPhone capabilities, such as sensors, GPS, Wi‐Fi, or Bluetooth connectivity. We observe that so far the development of iPhone applications has mostly been restricted to using Objective‐C. However, developing applications in plain Objective‐C on the iPhone OS suffers from limitations, such as the need for explicit memory management and lack of syntactic extension mechanism. Moreover, when developing distributed applications in Objective‐C, programmers have to manually deal with distribution concerns, such as service discovery, remote communication, and failure handling. In this paper, we discuss our experience in porting the Scheme programming language to the iPhone OS and how it can be used together with Objective‐C to develop iPhone applications. To support the interaction between Scheme programs and the underlying iPhone APIs, we have implemented a language symbiosis layer that enables programmers to access the iPhone SDK libraries from Scheme. In addition, we have designed high‐level distribution constructs to ease the development of distributed iPhone applications in an event‐driven style. We validate and discuss these constructs with a series of examples, including an iPod controller, a maps application, and a distributed multiplayer Scrabble‐like game. We discuss the lessons learned from this experience for other programming language ports to mobile platforms. Copyright © 2011 John Wiley & Sons, Ltd.     

Data Work: How Energy Advisors and Clients Make IoT Data Accountable

We present fieldwork findings from the deployment of an interactive sensing system that supports the work of energy advisors who give face-to-face advice to low-income households in the UK. We focus on how the system and the data it produced are articulated in the interactions between professional energy advisors and their clients, and how they collaboratively anticipate, rehearse, and perform data work. In addition to documenting how the system was appropriated in advisory work, we elaborate the ‘overhead cost’ of building collaborative action into connected devices and sensing systems, and the commensurate need to support discrete workflows and accountability systems to enable the methodical incorporation of the IoT into collaborative action. We contribute an elaboration of the social, collaborative methods of data work relevant to those who seek to design and study collaborative IoT systems.     

The Roles of Coenzyme Q in Disease: Direct and Indirect Involvement in Cellular Functions

Coenzyme Q (CoQ) is a key component of the respiratory chain of all eukaryotic cells. Its function is closely related to mitochondrial respiration, where it acts as an electron transporter. However, the cellular functions of coenzyme Q are multiple: it is present in all cell membranes, limiting the toxic effect of free radicals, it is a component of LDL, it is involved in the aging process, and its deficiency is linked to several diseases. Recently, it has been proposed that coenzyme Q contributes to suppressing ferroptosis, a type of iron-dependent programmed cell death characterized by lipid peroxidation. In this review, we report the latest hypotheses and theories analyzing the multiple functions of coenzyme Q. The complete knowledge of the various cellular CoQ functions is essential to provide a rational basis for its possible therapeutic use, not only in diseases characterized by primary CoQ deficiency, but also in large number of diseases in which its secondary deficiency has been found.     

New avenue for mid-UV-range detection of underivatized carbohydrates and amino acids in capillary electrophoresis

Capillary electrophoresis (CE) appeared as an interesting alternative to chromatographic methods for carbohydrate analysis, but it can be difficult to implement, because of the lack of easily ionizable functions and chromophore groups. Recently, a promising method was proposed by Rovio et al. for the CE separation under extremely high alkaline conditions of neutral carbohydrates under their alcoholate form and their direct UV detection [Rovio et al. Electrophoresis 2007, 28, 3129-3135; and Rovio et al. J. Chromatogr. A 2008, 1185, 139-144], which is claimed to be due to the absorption of enediolate at 270 nm. Even so, most of the detected compounds in Rovio's paper (for example, sucrose) cannot give such enediolate, lacking a carbonyl group. In this work, a deeper insight was paid to the understanding of detection mechanism. In effect, unusual detection phenomena were observed in comparing reducing and nonreducing carbohydrate behaviors, which pointed to the existence of photochemical reactions in the detection window. A more systematic study of the influence of many parameters (carbohydrate nature, electrolyte pH, residence time in the detection window, and capillary diameter) was undertaken. In addition to this, most of this work was performed under cathodic (reversed) electro-osmotic flow conditions (using Polybrene-modified capillaries), to obtain much faster separations than under Rovio's conditions. This study also opens up new avenues for the detection in mid-UV range of non-UV-absorbing compounds bearing reducing moieties, such as amino acids.     

Analysis of the use of voltammetric results as a steady state approximation to evaluate kinetic parameters of the hydrogen evolution reaction

The use of the voltammetric response j^vol(η) of a potentiodynamic sweep at a slow scan rate vs in place of a steady state polarization curve j^ss(η) for the determination of the kinetic parameters of the hydrogen evolution reaction is analyzed. It is proposed to consider jvol(η,vs)≅jss(η) when the condition 0.99≤jvol(η,vs)/jss(η)≤1.01 is verified in the overpotentials range η ≤ −0.05 V. It has been also established a simple relationship between the maximum admissible scan rate and the equilibrium polarization resistance R_p. Finally, the application of this criterion on different electrodes is described and discussed.     

Design of Engineered Elastomeric Substrate for Stretchable Active Devices and Sensors

In the field of flexible electronics, emerging applications require biocompatible and unobtrusive devices, which can withstand different modes of mechanical deformation and achieve low complexity in the fabrication process. Here, the fabrication of a mesa‐shaped elastomeric substrate, supporting thin‐film transistors (TFTs) and logic circuits (inverters), is reported. High‐relief structures are designed to minimize the strain experienced by the electronics, which are fabricated directly on the pillars' surface. In this design configuration, devices based on amorphous indium‐gallium‐zinc‐oxide can withstand different modes of deformation. Bending, stretching, and twisting experiments up to 6 mm radius, 20% uniaxial strain, and 180° global twisting, respectively, are performed to show stable electrical performance of the TFTs. Similarly, a fully integrated digital inverter is tested while stretched up to 20% elongation. As a proof of the versatility of mesa‐shaped geometry, a biocompatible and stretchable sensor for temperature mapping is also realized. Using pectin, which is a temperature‐sensitive material present in plant cells, the response of the sensor shows current modulation from 13 to 28 °C and functionality up to 15% strain. These results demonstrate the performance of highly flexible electronics for a broad variety of applications, including smart skin and health monitoring.