31 research outputs found
Dielectrophoretic assembly of insulinoma cells and fluorescent nanosensors into three-dimensional pseudo-islet constructs
No full textDielectrophoretic forces, generated by radio-frequency voltages applied to micromachined, transparent, indium tin oxide electrodes, have been used to condense suspensions of insulinoma cells (BETA-TC-6 and INS-1) into a 10times10 array of three-dimensional cell constructs. Some of these constructs, measuring ~150 mum in diameter, 120 mum in height and containing around 1000 cells, were of the same size and cell density as a typical islet of Langerhans. With the dielectrophoretic force maintained, these engineered cell constructs were able to withstand mechanical shock and fluid flow forces. Reproducibility of the process required knowledge of cellular dielectric properties, in terms of membrane capacitance and membrane conductance, which were obtained by electrorotation measurements. The ability to incorporate fluorescent nanosensors, as probes of cellular oxygen and pH levels, into these 'pseudo-islets' was also demonstrated. The footprint of the 10times10 array of cell constructs was compatible with that of a 1536 microtitre plate, and thus amenable to optical interrogation using automated plate reading equipment
Dielectrophoretic tweezer for isolating and manipulating target cells
No full textThe ability to isolate and accurately position single cells in three dimensions is becoming increasingly important in many areas of biological research. The authors describe the design, theoretical modelling and testing of a novel dielectrophoretic (DEP) tweezer for picking out and relocating single target cells. The device is constructed using facilities available in most electrophysiology laboratories, without the requirement of sophisticated and expensive microfabrication technology, and offers improved practical features over previously reported DEP tweezer designs. The DEP tweezer has been tested using transfected HEI-193 human schwannoma cells, with visual identification of the target cells being aided by labelling the incorporated gene product with a green fluorescent protei
Devices and techniques for the dielectrophoretic characterisation and manipulation of cells
No full textEThOS - Electronic Theses Online ServiceGBUnited Kingdo
Death by a Thousand Cuts? Green Tech, Traditional Knowledge, and Genocide
No full textTraditional Knowledge is a system of knowledge that is passed down through generations of Indigenous and Ethnic Minority Peoples throughout the world. A subset of Traditional Knowledge is Traditional Ecological Knowledge. These knowledge systems are incorporated throughout various international instruments and are considered vital to ways of life for Indigenous and Ethnic Minority Peoples. The author examines the elimination of Traditional Knowledge as a result of green technology. With discussions surrounding ways to obtain “net zero” in response to climate change, the author (re)introduces the notion that the irresponsible push for carbon zero technologies has a horrendous impact on the homelands of Indigenous and Ethnic Minority Peoples and leads to the eradication of Traditional Knowledge systems and its subset, Traditional Ecological Knowledge, thereby resulting in genocide. The author suggests that the actus reus element in genocide should be expanded to include elimination of Traditional Knowledge
Dielectrophoresis: A Review of Applications for Stem Cell Research
No full textDielectrophoresis can discriminate distinct cellular identities in heterogeneous populations, and monitor cell state changes associated with activation and clonal expansion, apoptosis, and necrosis, without the need for biochemical labels. Demonstrated capabilities include the enrichment of haematopoetic stem cells from bone marrow and peripheral blood, and adult stem cells from adipose tissue. Recent research suggests that this technique can predict the ultimate fate of neural stem cells after differentiation before the appearance of specific cell-surface proteins. This review summarises the properties of cells that contribute to their dielectrophoretic behaviour, and their relevance to stem cell research and translational applications.</p
A New Future? The Catholic Church, Grassroots Justice, and Accountability
No full textBetween the 1970s and 1980s, Guatemalans, particularly the indigenous populations, were targets of a state-sponsored genocide. Several years after the genocide, Catholic Bishop Juan Gerardi of Guatemala City took the lead in creating the Recovery of Historical Memory Project which was an independent investigation into the events of the genocide. Gerardi was murdered before the report was made public. This paper will briefly discuss Gerardi’s work and his contribution to local justice in Guatemala. The author will then explore what contributions the Catholic Church could make in creating similar fact-finding missions. Could a grassroots mechanism such as the one Gerardi created be a more effective response in particular situations, given the political gridlock of local and national governments? This paper will explore this question and utilize an ongoing situation to examine whether it could be more effective than a government body
A New Dawn? Statelessness and Assam
No full textThis article explores the ongoing crisis of statelessness that has been created because of a petition made by the people of Assam, India to update the electoral rolls in the state. As a result of the process, which has been approved by the Supreme Court of India, an estimated 4 million people have become stateless. The government has stated that these 4 million people risk deportation back to Bangladesh. This article will briefly examine the history of the situation that has unfolded in Assam; discuss the role of statelessness and how it may lead to genocide, underscoring the importance to act and find robust solutions. Finally, the author will conclude by discussing potential actions that India should take in order to resolve future cases of statelessness, specifically examining the Global Compact on Refugees and other instruments provided for within international refugee law. 
