ABSTRACT

A telemetry system based on Bluetooth Low Energy (BLE) was constructed to simultaneously collect locomotor activity and physiological signals of small animal cohorts for circadian rhythm experiments; it consists of miniature transmitters and mobile phone with customized App. The continuous sampling signals obtained from the 3-axis acceleration and temperature sensors in the transmitters are sent to the mobile phone in real-time through Internet of Things (IoT) for temporary storage and then imported into the computer for summary and rhythm analysis by the general open-source mathematical software. Unlike expensive and complicated commercial telemetry systems with industrial wireless standards, no special data receivers and software are needed. In our validation experiment, six rats were divided into two groups under natural dark and light-dark cycles. For two consecutive weeks, the transmitter mounted on the head of the rat-recorded locomotor activity, skin temperature, and ambient temperature of each rat at a frequency of 6 Hz. After processing with Local Weighted Regression Scatter Smoothing (LOWESS) and Fast Fourier Transform (FFT) filtering, single cosinor and multi-components cosinor were then used to assess and characterize the circadian rhythm. The results showed that the rhythm values of the two groups of rats coincided with the corresponding light-dark cycle, and that the system was robust to data loss and error from BLE communication failures. Therefore, the proposed system provides a light-weight framework for long-term circadian rhythm monitoring in free-moving rodents to further simplify and promote experimental chronobiology animal studies.

摘要

构建了基于蓝牙低功耗（BLE）的遥测系统，以同时收集小动物群的运动活动和生理信号以进行昼夜节律实验；它由微型发射机和带有定制App的手机组成。从变送器中的3轴加速度和温度传感器获得的连续采样信号通过物联网（IoT）实时发送到手机以进行临时存储，然后导入到计算机中以进行摘要和节奏分析。通用开源数学软件。与具有工业无线标准的昂贵和复杂的商业遥测系统不同，不需要特殊的数据接收器和软件。在我们的验证实验中 将六只大鼠在自然黑暗和明暗循环下分为两组。连续两个星期，将发射器安装在大鼠的头上，以6 Hz的频率记录每只大鼠的运动活动，皮肤温度和环境温度。经过局部加权回归散射平滑（LOWESS）和快速傅立叶变换（FFT）滤波处理后，然后使用单余弦和多分量余弦来评估和表征昼夜节律。结果表明，两组大鼠的节律值与相应的明暗周期一致，并且该系统对于数据丢失和BLE通信失败所造成的错误具有鲁棒性。因此，