Recording advances for neural prosthetics

An important challenge for neural prosthetics research is to record from populations of neurons over long periods of time, ideally for the lifetime of the patient. Two new advances toward this goal are described, the use of local field potentials (LFPs) and autonomously positioned recording electrodes. LFPs are the composite extracellular potential field from several hundreds of neurons around the electrode tip. LFP recordings can be maintained for longer periods of time than single cell recordings. We find that similar information can be decoded from LFP and spike recordings, with better performance for state decodes with LFPs and, depending on the area, equivalent or slightly less than equivalent performance for signaling the direction of planned movements. Movable electrodes in microdrives can be adjusted in the tissue to optimize recordings, but their movements must be automated to be a practical benefit to patients. We have developed automation algorithms and a meso-scale autonomous electrode testbed, and demonstrated that this system can autonomously isolate and maintain the recorded signal quality of single cells in the cortex of awake, behaving monkeys. These two advances show promise for developing very long term recording for neural prosthetic applications

Undergraduate module on nutrition education and communication for Africa: Profiles of potential students

To be adequately nourished, individuals need to have access to sufficient and good quality food. They also need to have an understanding of what constitutes a good diet for health, and have the skills and motivation to make good food choices. Nutrition education equips people to make such choices. Building countries’ capacities to provide effective nutrition education and promote healthy diets is part of the work carried out by the Nutrition Division of the Food and Agriculture Organization (FAO) of the United Nations. The FAO Effective Education for Nutrition in Action (ENACT) project is assisting countries to develop institutional and professional capacities in nutrition education in Africa by producing a basic module on nutrition education at undergraduate level for use by national universities and other training institutions. The course materials will be available for online, face-to-face or blended use and are being piloted and revised to improve and adapt them to local context and consumer need. Creating a learner profile is an accepted step in course design, particularly important in situations where course developers do not have close contact with the students, as in this case. The ENACT learner profile was compiled from replies to a short questionnaire of 32 questions administered to a sample of students. The respondents were the actual piloting students, or were representative of those who would be piloting the course. One hundred and twenty eight responses were received from universities in Ethiopia, Ghana, Kenya, Nigeria, Tanzania and Uganda, approximately 20 per university. On average, respondents answered 96% of the questions in the questionnaire. Information was obtained on areas such as students’ social/cultural  interests; food and nutrition experience and expertise; food and eating habits; ideas of nutrition education and training in nutrition education; and study preferences. In addition, the profile of a typical learner in each country (including age, gender and information on socio-economic  background, urban/rural background and English proficiency) was compiled from the questionnaires and from additional information supplied by the tutors. The study findings have helped the course developers to select course content and structure learning activities to meet students’ needs and circumstances.Key words: professional training, nutrition education, Afric

Possible Metal/Insulator Transition at B=0 in Two Dimensions

We have studied the zero magnetic field resistivity of unique high- mobility two-dimensional electron system in silicon. At very low electron density (but higher than some sample-dependent critical value, $n_{cr}\sim 10^{11}$ cm$^{-2}$), CONVENTIONAL WEAK LOCALIZATION IS OVERPOWERED BY A SHARP DROP OF RESISTIVITY BY AN ORDER OF MAGNITUDE with decreasing temperature below 1--2 K. No further evidence for electron localization is seen down to at least 20 mK. For $n_s<N_{cr}$, the sample is insulating. The resistivity is empirically found to SCALE WITH TEMPERATURE BOTH BELOW AND ABOVE $n_{cr}$ WITH A SINGLE PARAMETER which approaches zero at $n_s=n_{cr}$ suggesting a metal/ insulator phase transition.Comment: 10 pages; REVTeX v3.0; 3 POSTSCRIPT figures available upon request; to be published in PRB, Rapid Commu

Maternal mortality in the rural Gambia, a qualitative study on access to emergency obstetric care

BACKGROUND: Maternal mortality is the vital indicator with the greatest disparity between developed and developing countries. The challenging nature of measuring maternal mortality has made it necessary to perform an action-oriented means of gathering information on where, how and why deaths are occurring; what kinds of action are needed and have been taken. A maternal death review is an in-depth investigation of the causes and circumstances surrounding maternal deaths. The objectives of the present study were to describe the socio-cultural and health service factors associated with maternal deaths in rural Gambia. METHODS: We reviewed the cases of 42 maternal deaths of women who actually tried to reach or have reached health care services. A verbal autopsy technique was applied for 32 of the cases. Key people who had witnessed any stage during the process leading to death were interviewed. Health care staff who participated in the provision of care to the deceased was also interviewed. All interviews were tape recorded and analyzed by using a grounded theory approach. The standard WHO definition of maternal deaths was used. RESULTS: The length of time in delay within each phase of the model was estimated from the moment the woman, her family or health care providers realized that there was a complication until the decision to seeking or implementing care was made. The following items evolved as important: underestimation of the severity of the complication, bad experience with the health care system, delay in reaching an appropriate medical facility, lack of transportation, prolonged transportation, seeking care at more than one medical facility and delay in receiving prompt and appropriate care after reaching the hospital. CONCLUSION: Women do seek access to care for obstetric emergencies, but because of a variety of problems encountered, appropriate care is often delayed. Disorganized health care with lack of prompt response to emergencies is a major factor contributing to a continued high mortality rate

Abstracts from the 50th European Society of Human Genetics Conference: Posters

International audienc

Hybrid additive manufacturing of 3D electronic systems

A novel hybrid additive manufacturing (AM) technology combining digital light projection (DLP) stereolithography (SL) with 3D micro-dispensing alongside conventional surface mount packaging is presented in this work. This technology overcomes the inherent limitations of individual AM processes and integrates seamlessly with conventional packaging processes to enable the deposition of multiple materials. This facilitates the creation of bespoke end-use products with complex 3D geometry and multi-layer embedded electronic systems. Through a combination of four-point probe measurement and non-contact focus variation microscopy, it was identified that there was no obvious adverse effect of DLP SL embedding process on the electrical conductivity of printed conductors. The resistivity maintained to be less than 4  ×  10−4 Ω centerdot cm before and after DLP SL embedding when cured at 100 °C for 1 h. The mechanical strength of SL specimens with thick polymerized layers was also identified through tensile testing. It was found that the polymerization thickness should be minimised (less than 2 mm) to maximise the bonding strength. As a demonstrator a polymer pyramid with embedded triple-layer 555 LED blinking circuitry was successfully fabricated to prove the technical viability

The impacts of environmental warming on Odonata: a review

Climate change brings with it unprecedented rates of increase in environmental temperature, which will have major consequences for the earth's flora and fauna. The Odonata represent a taxon that has many strong links to this abiotic factor due to its tropical evolutionary history and adaptations to temperate climates. Temperature is known to affect odonate physiology including life-history traits such as developmental rate, phenology and seasonal regulation as well as immune function and the production of pigment for thermoregulation. A range of behaviours are likely to be affected which will, in turn, influence other parts of the aquatic ecosystem, primarily through trophic interactions. Temperature may influence changes in geographical distributions, through a shifting of species' fundamental niches, changes in the distribution of suitable habitat and variation in the dispersal ability of species. Finally, such a rapid change in the environment results in a strong selective pressure towards adaptation to cope and the inevitable loss of some populations and, potentially, species. Where data are lacking for odonates, studies on other invertebrate groups will be considered. Finally, directions for research are suggested, particularly laboratory studies that investigate underlying causes of climate-driven macroecological patterns

Women-focused development intervention reduces delays in accessing emergency obstetric care in urban slums in Bangladesh: a cross-sectional study

<p>Abstract</p> <p>Background</p> <p>Recognizing the burden of maternal mortality in urban slums, in 2007 BRAC (formally known as Bangladesh Rural Advancement Committee) has established a woman-focused development intervention, Manoshi (the Bangla abbreviation of mother, neonate and child), in urban slums of Bangladesh. The intervention emphasizes strengthening the continuum of maternal, newborn and child care through community, delivery centre (DC) and timely referral of the obstetric complications to the emergency obstetric care (EmOC) facilities. This study aimed to assess whether Manoshi DCs reduces delays in accessing EmOC.</p> <p>Methods</p> <p>This cross-sectional study was conducted during October 2008 to January 2009 in the slums of Dhaka city among 450 obstetric complicated cases referred either from DCs of Manoshi or from their home to the EmOC facilities. Trained female interviewers interviewed at their homestead with structured questionnaire. <it>Pearson's </it>chi-square test, <it>t</it>-test and Mann-Whitney test were performed.</p> <p>Results</p> <p>The median time for making the decision to seek care was significantly longer among women who were referred from home than referred from DCs (9.7 hours vs. 5.0 hours, p < 0.001). The median time to reach a facility and to receive treatment was found to be similar in both groups. Time taken to decide to seek care was significantly shorter in the case of life-threatening complications among those who were referred from DC than home (0.9 hours vs.2.3 hours, p = 0.002). Financial assistance from Manoshi significantly reduced the first delay in accessing EmOC services for life-threatening complications referred from DC (p = 0.006). Reasons for first delay include fear of medical intervention, inability to judge maternal condition, traditional beliefs and financial constraints. Role of gender was found to be an important issue in decision making. First delay was significantly higher among elderly women, multiparity, non life-threatening complications and who were not involved in income-generating activities.</p> <p>Conclusions</p> <p>Manoshi program reduces the first delay for life-threatening conditions but not non-life-threatening complications even though providing financial assistance. Programme should give more emphasis on raising awareness through couple/family-based education about maternal complications and dispel fear of clinical care to accelerate seeking EmOC.</p