56 research outputs found
A CMOS-based neural implantable optrode for optogenetic stimulation and electrical recording
This paper presents a novel integrated optrode for simultaneous optical stimulation and electrical recording for closed -loop optogenetic neuro-prosthetic applications. The design has been implemented in a commercially available 0.35Ī¼m CMOS process. The system includes circuits for controlling the optical stimulations; recording local field potentials (LFPs); and onboard diagnostics. The neural interface has two clusters of stimulation and recording sites. Each stimulation site has a bonding point for connecting a micro light emitting diode (Ī¼LED) to deliver light to the targeted area of brain tissue. Each recording site is designed to be post-processed with electrode materials to provide monitoring of neural activity. On-chip diagnostic sensing has been included to provide real-time diagnostics for post-implantation and during normal operation
Research priorities for improving infant and young child feeding in humanitarian emergencies
Background
There are many challenges during emergencies to ensure that optimal infant and young child feeding is protected, promoted and supported, but there is a dearth of evidence on strategies and programmes to improve Infant and Young Child Feeding in Emergencies (IYCF-E) and a need to determine research priorities.
Methods
Based on interviews with key informants who are experts in the subject, we developed a list of 48 research questions on IYCF-E. A framework, following the Child Health and Nutrition Research Initiative method to set priorities in child health research, was developed to rank the research questions. Four criteria were applied to create a ranking based on answerability, operational relevance, disease burden reduction and prevention, and originality. Using an on-line survey, prioritisation of research questions was done by 27 people from 14 NGOs, universities and research institutions, and UN organisations.
Results
The top-ten research questions identified focused on the following:
ā¢ Use of cash-transfer to buy breast-milk substitutes;
ā¢ Effectiveness of complementary feeding strategies;
ā¢ Long-term effect of IYCF-E interventions;
ā¢ Design of IYCF-E programmes in a context where breastfeeding rates are low and breast milk substitutes use is high;
ā¢ Design of effective re-lactation interventions;
ā¢ Provision of psychological support to young childrenās care-takers;
ā¢ Determination of number of beneficiaries and coverage of IYCF-E programmes;
ā¢ Pros and cons of distributing ready-to-use infant formula compared with distributing powdered infant formula plus kit for safer use of BMS, when use of infant formula is necessary;
ā¢ Assessment of the impact of specific IYCF-E programmes on nutritional status, morbidity and mortality;
ā¢ Linking and mainstreaming IYCF-E interventions with other sectors such as health, WASH, food security and child protection.
Conclusion
The questions found by this study could form the basis of future research on IYCF-E and could be integrated into the agenda of relevant stakeholders. Results of studies based on these questions will be fundamental to fill the evidence gap in IYCF-E, improve IYCF-E programming and ultimately contribute to the reduction in morbidity and mortality among infants and young children in humanitarian emergencies
High speed single pixel imaging with advanced microLED digital light projector
We demonstrate high speed single pixel imaging using an advanced microLED-on-CMOS array. We show 128x128 pixel image reconstruction at an effective frame rate of 3.8fps and lower resolution reconstructions at over 120fps. The method is demonstrated to be compatible with common compressive imaging techniques
High speed single pixel imaging using a MicroLED-on-CMOS light projector
Achieving high frame-rate operation in single pixel imaging schemes normally demands significant compromises in the flexibility of the imaging system, requiring either complex optical setups or a hardware-limited pattern mask set. Here, we demonstrate a single pixel imaging capability with pattern frame-rates approaching 400 kfps with a recently developed microLED light projector and an otherwise simple optical setup. The microLED array has individually addressable pixels and can operate significantly faster than Digital Micromirror Devices, allowing flexibility with regards to the pattern masks employed for imaging even at the fastest frame-rates. Using a full set of Hadamard or Noiselet patterns, we demonstrate 128 Ć 128 pixel images being generated at 7.3 fps. We generate a pattern set specifically for the light projector using deep learning tools and use these patterns to demonstrate single pixel imaging at almost 800 fps
An optrode with built-in self-diagnostic and fracture sensor for cortical brain stimulation
This paper proposes a self-diagnostic subsystem for a new generation of brain implants with active electronics. The primary objective of such probes is to deliver optical pulses to optogenetic tissue and record the subsequent activity, but lifetime is currently unknown. Our proposed circuits aim to increase the safety of implanting active electronic probes into human brain tissue. Therefore, prolonging the lifetime of the implant and reducing the risks to the patient. The self-diagnostic circuit will examine the optical emitter against any abnormality or malfunctioning. The fracture sensor examines the optrode against any rapture or insertion breakage. The optrode including our diagnostic subsystem and fracture sensor has been designed and successfully simulated at 350nm AMS technology node and sent for manufacture
Effect of 8-Week Endurance, Resistance and Concurrent Trainings on Serum Leptin Concentration Changes and Some Regulator Hormones of Blood Glucose in Athlete Male Students
Introduction: The purpose of the present study was to compare the effect of three different types of training programs on serum leptin concentration changes and some regulator hormones of blood glucose in athlete male students.
Methods: In this quasi-experimental study, 32 athlete male students were randomly divided into 4 groups: endurance (END), resistance (RES), concurrent (CON) and control (CONT). In an 8-week training, subjects in END group performed 4 sessions per week running on treadmill with 65% heart rate maximum for 45 minutes; RES group received 4 sessions per week consisting of a 9-item circuit resistance of 4 sets with 12 repetitions and intensity of 60% and one repetition maximum . Moreover, CON group performed both of RES and END training protocols. Blood samples were taken before, immediately and 24 hours after last session training. The study results were analyzed using repeated measures Anova (Pā¤0.05).
Results: Immediately after exercise, serum leptin concentration decreased significantly in all groups (Pā¤0.05), whereas 24 hours after exercise it increased that was significant in END and RES groups (Pā¤0.001). Cortisol levels increased immediately after exercise though that was not significant. In contrary, it decreased 24 hours after training that was significant just in RES group (Pā¤0.035). Insulin levels decreased, though, not significantly immediately after exercise, whereas it increased 24 hours after exercise significantly in END (Pā¤0.045) and RES groups (Pā¤0.004). Growth hormone also increased immediately and 24 hours after exercise which was not significant in any groups.
Conclusion: Serum leptin levels revealed higher decrease in CON group compared to other groups that is probably due to high intensity and long exercise period and more adipose tissue reduction
Gain enhancement of circular waveguide antennas using near-zero index metamaterials
In this article, a rigorous analytical methodology is introduced for designing near-zero refractive index metamaterials (NZIMs). Our proposed NZIM media is realized by three stacked layers of perforated metallic surfaces, each layer composed of a fishnet-like periodic array of square holes. By a proper design of such structures, a low refractive index medium is achieved at their corresponding plasma frequency. The low refractive index property is studied by retrieving the effective parameters of NZIM via inversion techniques, which gives an effective near-zero refractive index, at an operating frequency of 1.5 GHz. Then, the designed NZIM is used for gain enhancement of a circular waveguide antenna. The analysis shows that the proposed platform can enhance the directivity of our antenna by 3 dB while maintaining the return loss <ā20 dB. Ā© 2019 Wiley Periodicals, Inc
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