Wireless battery free fully implantable multimodal recording and neuromodulation tools for songbirds

Wireless battery free and fully implantable tools for the interrogation of the central and peripheral nervous system have quantitatively expanded the capabilities to study mechanistic and circuit level behavior in freely moving rodents. The light weight and small footprint of such devices enables full subdermal implantation that results in the capability to perform studies with minimal impact on subject behavior and yields broad application in a range of experimental paradigms. While these advantages have been successfully proven in rodents that move predominantly in 2D, the full potential of a wireless and battery free device can be harnessed with flying species, where interrogation with tethered devices is very difficult or impossible. Here we report on a wireless, battery free and multimodal platform that enables optogenetic stimulation and physiological temperature recording in a highly miniaturized form factor for use in songbirds. The systems are enabled by behavior guided primary antenna design and advanced energy management to ensure stable optogenetic stimulation and thermography throughout 3D experimental arenas. Collectively, these design approaches quantitatively expand the use of wireless subdermally implantable neuromodulation and sensing tools to species previously excluded from in vivo real time experiments.

INVESTIGATION OF LOCALIZED SKIN TEMPERATURE DISTRIBUTION ACROSS THE TRANSTIBIAL RESIDUAL LIMB

BACKGROUND: Interventions to resolve thermal discomfort as a common complaint in amputees are usually chosen based on the residual limb skin temperature while wearing prosthesis; whereas, less attention has been paid to residual limb skin temperature while outside of the prosthesis. The objective of this study was to explore the localized and regional skin temperature over the transtibial residual limb (TRL) while outside of the prosthesis. METHODOLOGY: Eight unilateral transtibial adults with traumatic amputation were enrolled in this cross-sectional study. Participants sat to remove their prostheses and rested for 30 minutes. Twelve sites were marked circumferentially in four columns (anterolateral, anteromedial, posteromedial, and posterolateral) and longitudinally in three rows (proximal, middle, and distal) over the residual limb and used for attachment of analog thermistors. Skin temperature was recorded and compared for 11 minutes. Furthermore, the relationship of skin temperature with participants’ demographic and clinical characteristics was explored. FINDINGS: The whole temperature of the TRL was 27.73 (SD=0.83)°C. There was a significant difference in skin temperature between anterior and posterior columns. Likewise, the distal row was significantly different from the proximal and middle rows. The mean temperature at the middle and distal zones of the anteromedial column had the highest and lowest skin temperatures (29.8 and 26.3°C, p<0.05), respectively. The mean temperature of the whole TRL had no significant relationships (p>0.05) with participants’ demographic and clinical characteristics. CONCLUSIONS: An unequal distribution of temperature over the TRL was found with significantly higher and lower temperatures at its anterior column and distal row, respectively. This temperature pattern should be considered for thermoregulation strategies. Further investigation of the residual limb temperature with and without prosthesis, while considering muscles thickness and blood perfusion rate is warranted. Layman's Abstract The socket is a plastic hard-shell interface between the residual limb, the remaining part of the amputated limb, and a prosthesis. Heat buildup inside the prosthetic socket and perspiration of the residual limb are major discomforts in amputees when wearing a prosthesis. The majority of prior research measured residual limb skin temperature while the prosthesis was worn. However, less attention has been paid to skin temperature without prostheses. Skin temperature of eight adults with one-sided traumatic below-knee amputation was measured. Participants sat and removed their prostheses. Twelve anatomical sites were marked circumferentially in four columns and longitudinally in three rows over the residual limb and used for temperature recording using temperature sensors. The whole temperature of the residual limb was 27.73 (SD=0.83)°C. Skin temperature was higher at anterior columns compared to posterior columns. Similarly, the distal row of the residual limb had the lowest temperature compared to its middle and proximal rows. From a localized standpoint, the middle part at the anterior medial surface of the residual limb had the highest temperature, whereas the distal part at the anterior-medial surface had the lowest skin temperature. There was no noticeable relationship between the average of the residual limb skin temperature and participants’ demographic and clinical characteristics. Some strategies need to be developed to regulate and control heat dissipation over the residual limb's surface when amputees do not wear prostheses. Further temperature recording research by considering muscle thickness and arterial blood flow rate of the residual limb with and without prosthesis is suggested. Article PDF Link: https://jps.library.utoronto.ca/index.php/cpoj/article/view/35070/27313 How To Cite: Ghoseiri K, Allami M, Murphy J.R, Page P, Button D.C. Investigation of localized skin temperature distribution across the transtibial residual limb. Canadian Prosthetics & Orthotics Journal. 2021;Volume 4, Issue 1, No.2. https://doi.org/10.33137/cpoj.v4i1.35070 Corresponding Author: Duane C Button, PhDSchool of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John’s, Newfoundland, Canada.E-mail: [email protected]: https://orcid.org/0000-0001-6402-8545

Investigation of Thermal Fields at Phase Boundaries in Powder Mixtures that are Subject to Melting and Chemical Transformation

An important part of the process of parts hardening by the induction surfacing method is the heating of hard alloy particles and flux in charge mixture. The article describes comprehensive studies on measurement and simulation of temperatures at phase boundaries in complex melting and heat-sensitive powder mixtures. To record the temperature in the induction surfacing process, it is proposed to apply CA micro-thermocouple method and the thermal indication method using SHS compositions. The developed methods for complex temperature recording in the process of induction surfacing allow to determine the melting temperature of the charge mixture and its single components.

Smart Vehicle Automation Using Internet of Things

The field of automobile automation, though relatively new, has taken over the world by storm with the advent of driverless cars and smart vehicles. While these vehicles provide various automation features like autopilot, auto cruise control and automatic braking which enhance the driving experience and ensure safety, there are not many provisions for further safety, driver protection and problem prevention. Keeping this in mind, we have proposed a very inexpensive model to monitor the driver’s state and the in-vehicle safety, with an automatic braking system, using various sensors—gas (detecting highly poisonous toxic gases), IR (seatbelts), alcohol (if the driver is drunk), temperature/flame (for fire inside and temperature recording), humidity, LDR (automatic headlights) and ZIGBEE (automatic braking). A 12 V DC motor (wheel) controlled by L298N. The vehicle status and the motor stop reason is displayed in a basic LCD display. The data collected in all these sensors is displayed in the cloud for analyses. Arduino was used for interconnection, automation and system control. NodeMCU for cloud connection. The whole system is powered by a 5 V power source.

High-power, Short-duration Radiofrequency Ablation for the Treatment of AF

High-power, short-duration (HPSD) ablation for the treatment of AF is emerging as an alternative to ablation using conventional ablation generator settings characterised by lower power and longer duration. Although the reported potential advantages of HPSD ablation include less tissue oedema and collateral tissue damage, a reduction in procedural time and superior ablation lesion formation, clinical studies of HPSD ablation validating these observations are limited. One of the main challenges for HPSD ablation has been the inability to adequately assess temperature and lesion formation in real time. Novel catheter designs may improve the accuracy of intra-ablation temperature recording and correspondingly may improve the safety profile of HPSD ablation. Clinical studies of HPSD ablation are on-going and interpretation of the data from these and other studies will be required to ascertain the clinical value of HPSD ablation.