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• A facile layer-by-layer method was developed to fabricate flexible conductive cotton fabric from chitosan and carbon nanotubes. • The fabric exhibited remarkable mechanical and electrical stability and could accurately detect human movements as a strain sensor. • The fabric can be used as a temperature sensor with reliable negative temperature sensing in the range of 30–100 °C. Layer-by-layer (LBL) assembly shows great potential in fabrication of flexible conductive cotton fabrics (FCCF) with carbon nanotubes (CNT) as conductive components but is limited because complicated chemical modification of CNT is usually required. Herein, we reported a facile and eco-friendly LBL approach to fabricating FCCF by dipping in chitosan (CS) aqueous solution and poly(sodium 4-styrenesulfonate) (PSS) wrapped CNT aqueous dispersion alternately. The FCCF with electrical conductivity higher than 30 S/m was achieved when 4 layers of CNT were coated on the cotton fabric (CF). The obtained FCCF possessed outstanding mechanical stability with electrical resistivity almost unchanged after exposure to 500 times mechanical abrasion and 500 circles of tape peeling. The FCCF showed excellent strain sensing performance with high sensitivity (with a gauge factor up to 35.1) and a fast response time (70 ms). It can be used as a strain sensor to accurately detect various human deformations such as finger bending and joint movements. The FCCF could be used as a temperature sensor in that it exhibited stable and reproducible negative temperature sensing behavior in the temperature range of 30–100 °C. [Display omitted] [ABSTRACT FROM AUTHOR]

A simple, stable, and high-sensitivity temperature sensor based on multimode interference (MMI) in a polymer optical fiber (POF) with higher-order mode excitation has been developed. In a single-mode-multimode-single-mode (SMS) structure, one of the two ends of the multimode POF with physical-contact (PC) connectors is connected to a silica single-mode fiber with an angled-PC (APC) connector to make use of higher-order propagation modes in the POF. Three configurations (no PC-APC, PC-APC at input, and PC-APC at output) are compared, and the maximal temperature sensitivity of 219.2 pm/°C, which is more than double the value of the standard (no PC-APC) SMS structure, is obtained. This result indicates that the temperature sensitivity can be stably enhanced at a low cost by the use of PC-APC connections. [ABSTRACT FROM AUTHOR]

In this paper we present a complete low-cost sensor system including fiber-optics, electronics, and data processing implemented on a simple microcontroller. The system can be operated stand-alone, showing real-time temperatures on a display or connected for data logging to a PC. Cheap ruby spheres or half-spheres from mass production are integrated in a small fiber-optic sensor head. All electronics including a high-power blue LED and a Si photodiode are easily integrated on a modified commercial add-on board on top of a Nucleo-64 development kit for STM32 microcontrollers. Temperature measurement is done by fitting the exponential decay of the ruby fluorescence after pulsed excitation. Calibration and testing was done in a climate chamber, achieving a temperature accuracy of 0.5 K within a range of -40°C to +80°C. [ABSTRACT FROM AUTHOR]

A new self-powered temperature-sensitive electronic-skin (e-skin) for real-time monitoring body temperature without external electricity power was fabricated from patterned polydimethylsiloxane/polyaniline (PDMS/PANI) nanostructures. The e-skin can be feasibly attached on the human body and driven by the mechanical motion energy through triboelectric effect. The outputting triboelectric impulse of the PDMS/PANI units is significantly dependent on the local surface temperature of the e-skin, serving as both the power source and temperature sensing signal. The outputting current of the e-skin increases with increasing surface temperature of the device. Under applied bending deformation, the response of the e-skin is up to 63.6 for 38.6 °C. The e-skin can detect minimum temperature change of 0.4 °C. The working mechanism can be ascribed to the coupling effect of triboelectric and semiconductor properties (tribotronic effect). A practical application of the e-skin attaching on the human body for detecting the body temperature range of 36.5–42.0 °C has been simply demonstrated. This work provides a viable method for real-time monitoring body temperature, and can promote the development of wearable temperature sensors and self-powered multifunctional nanosystems. [ABSTRACT FROM AUTHOR]

A wireless sensor network for condition monitoring and its corresponding sensor node powered by a vibration energy harvester producing about 100 \muW are presented. The sensor network utilizes an asynchronous beacon-detection based duty cycle control architecture to reduce power consumption and support ID-based TDMA while avoiding the need for timing synchronization between nodes. It also provides FDMA and fixed-time slot TDMA for further network flexibility. The sensor node transceiver includes a duty-cycle timing control unit to minimize power consumption; an LO-less, TDMA-capable, addressable beacon receiver; an FDMA-capable transmitter; and a low-power, universal sensor interface. The proposed sensor node, implemented in 0.13-\mum CMOS technology, achieves low power consumption and a high degree of flexibility without requiring calibration or the use of BAW or SAW filters. The sensor node is experimentally demonstrated to operate autonomously from the power provided by a piezoelectric vibration energy harvester with dimensions of 27\,\times\,23\,\times\,6.5 mm^3 excited by 4.5-m/s^2 acceleration at 40.8 Hz. The WSN condition monitoring behavior is measured with a capacitive temperature sensor, and achieves an effective temperature resolution of 0.36^\circC. [ABSTRACT FROM PUBLISHER]

Animals possess systems for sensing environmental temperature using temperature-sensitive ion channels called transient receptor potential channels (TRP5). Various TRPs have been identified and characterized in mammals. However, those of ectotherms, such as reptiles, are less well studied. Here, we identify the V subfamily of TRP (TRPV) in two reptile species: Japanese grass lizard (Takydromus tachydromoides) and Japanese four-lined ratsnake (Elaphe quadrivirgata). Phylogenetic analysis of TRPVs indicated that ectothermic reptilian TRPVs are more similar to those of endothermic chicken and mammals, than to other ectotherms, such as frog and fish. Expression analysis of TRPV4 mRNA in the lizard showed that its expression in tissues and organs is specifically controlled in cold environments and hibernation. The mRNA was ubiquitously expressed in seven tissuesiorgans examined. Both cold-treatment and hibernation lowered TRPV4 expression, but in a tissue/organ-specific manner. Cold-treatment reduced TRPV4 expression in tongue and muscle, while in hibernation it was reduced more widely in brain, tongue, heart, lung, and muscle. Interestingly, however, levels of TRPV4 mRNA in the skin remained unaffected after entering hibernation and cold-treatment, implying that TRPV4 in the skin may act as an environmental temperature sensor throughout the reptilian life cycle, including hibernation. This is the first report, to our knowledge, to describe reptilian TRPV4 in relation to hibernation. [ABSTRACT FROM AUTHOR]

The article presents a study which discusses improvement in temperature sensing of polymer fibre bragg grating (FBG) sensors with poly-dimethylsiloxane (PDMS) coating and mentions use of FBG sensors for sensing physical parameters such as temperature.