Metallized printed microstructures for precision biomedical recording and stimulation

Implantable electrodes are the central tool for many techniques and treatments in biomedical research and medicine. There is a trend in these tools towards arrays of tissue-penetrating microelectrodes with low geometric surface areas for purposes of both increasing the specificity of recording/stimulation and reducing tissue damage due to insertion trauma and reactive immune responses. However, smaller electrode sizes present new constraints – both difficulty in fabrication as well as significant limitations on effective charge storage/injection capacities as well as higher impedances, making smaller electrodes less capable of easily passing charge safely and efficiently. Fabricating structures on the scale of tens of microns and below poses significant challenges compared to well established machining at larger sizes. Established sets of techniques such as classic MEMS processes are limited to relatively specific shapes, with significant limitations in their ability to produce curved surfaces and surfaces which are not composed of highly distinct stepped layers. We developed a method for improvement of impedance and charge storage capacity of flat electrodes without affecting geometric surface area (footprint) using Resonant Direct Laser Writing (rDLW) 3D printing to fabricate high surface area 3D structures, which were then rendered conductive. The ability to perform DLW printing at a range of laser powers on opaque reflective surfaces is demonstrated, previously a known limitation of direct laser writing. This is demonstrated through a variety of example prints. This capability opens the door to many new possibilities in micron resolution polymer printing which were previously inaccessible, with potentially far reaching ramifications for microfabrication

Introduction: 'Some for All Rather than More for Some'? Contested Pathways and Politics since the 1990 New Delhi Statement

This introduction reviews the experience of the water and sanitation sector since the 1990 New Delhi Statement – Some for All Rather than More for Some. It explores the policy pathways and contested politics that took place as a result of three key years in the early 1990s, from the issuing of the New Delhi Statement in 1990, through the Dublin Statement on Water and Sustainable Development in 1992, to the output of the Earth Summit held in Rio de Janeiro. These key events have shaped policy and practice over a period of two decades, including generating major contestation over the idea of water as an economic good. Past lessons suggest that the wider global water and sanitation community needs to rethink approaches and emphases, shifting from targets and global pronouncement to issues concerning sustainability, global/local mismatches, contested knowledges, equity, politics and power

Printable microscale interfaces for long-term peripheral nerve mapping and precision control

The nascent field of bioelectronic medicine seeks to decode and modulate peripheral nervous system signals to obtain therapeutic control of targeted end organs and effectors. Current approaches rely heavily on electrode-based devices, but size scalability, material and microfabrication challenges, limited surgical accessibility, and the biomechanically dynamic implantation environment are significant impediments to developing and deploying advanced peripheral interfacing technologies. Here, we present a microscale implantable device – the nanoclip – for chronic interfacing with fine peripheral nerves in small animal models that begins to meet these constraints. We demonstrate the capability to make stable, high-resolution recordings of behaviorally-linked nerve activity over multi-week timescales. In addition, we show that multi-channel, current-steering-based stimulation can achieve a high degree of functionally-relevant modulatory specificity within the small scale of the device. These results highlight the potential of new microscale design and fabrication techniques for the realization of viable implantable devices for long-term peripheral interfacing.https://www.biorxiv.org/node/801468.fullFirst author draf

Printable microscale interfaces for long-term peripheral nerve mapping and precision control

Modulation of peripheral nervous system signalling has many applications in medicine, neurobiology and machine-man interfaces. Here the authors develop a microscale implantable device for chronic interfacing with a small diameter nerve, and show multi-week in vivo recording and control of activity

Sociology and international relations: legacies and prospects

While sociological concepts have often been implicitly used in International Relations (IR), recent years have seen a more explicit engagement between IR and Sociology. As with any such interdisciplinary assignation, there are both possibilities and challenges contained within this move: possibilities in terms of reducing IR's intellectual autism and opening the discipline towards potentially fertile terrain that was never, actually, that distant; challenges in that interdisciplinary raiding parties can often serve as pseudonyms for cannibalism, shallowness and dilettantism. This forum reviews the sociological turn in IR and interrogates it from a novel vantage point—how sociologists themselves approach IR concepts, debates and issues. Three sociological approaches—classical social theory, historical sociology and Foucauldian analysis—are critically deployed to illuminate IR concerns. In this way, the forum offers the possibility of (re)establishing exchanges between the two disciplines premised on a firmer grasp of social theory itself. The result is a potentially more fruitful sociological turn, one with significant benefits for IR as a whole

The water poverty index: development and application at the community scale

The article details the development and uses of the water poverty index (WPI). The index was developed as a holistic tool to measure water stress at the household and community levels, designed to aid national decision makers, at community and central government level, as well as donor agencies, to determine priority needs for interventions in the water sector. The index combines into a single number a cluster of data directly and indirectly relevant to water stress. Subcomponents of the index include measures of: access to water; water quantity, quality and variability; water uses (domestic, food, productive purposes); capacity for water management; and environmental aspects. The WPI methodology was developed through pilot projects in South Africa, Tanzania and Sri Lanka and involved intensive participation and consultation with all stakeholders, including water users, politicians, water sector professionals, aid agency personnel and others. The article discusses approaches for the further implementation of the water poverty index, including the possibilities of acquiring the necessary data through existing national surveys or by establishing interdisciplinary water modules in school curricula. The article argues that the WPI fills the need for a simple, open and transparent tool, one that will appeal to politicians and decision makers, and at the same time can empower poor people to participate in the better targeting of water sector interventions and development budgets in general