Changes In Environmental Temperature Research Articles

The Molecular Mechanism of Clock in Thermal Adaptation of Two Congeneric Oyster Species

Clock genes regulate physiological and metabolic processes by responding to changes in environmental light and temperature, and genetic variations in these genes may facilitate environmental adaptation, offering opportunities for resilience to climate change. However, the genetic and molecular mechanisms remain unclear in marine organisms. In this study, we investigated the role of a key clock gene, the circadian locomotor output cycles kaput (Clock), in thermal adaptation using DNA affinity purification sequencing (DAP-Seq) and RNA interference (RNAi)-based transcriptome analysis. In cold-adapted Crassostrea gigas and warm-adapted Crassostrea angulata, Clock was subject to environmental selection and exhibited contrasting expression patterns. The transcriptome analysis revealed 2054 differentially expressed genes (DEGs) following the knockdown of the Clock expression, while DAP-Seq identified 150,807 genes regulated by Clock, including 5273 genes located in promoter regions. The combined analyses identified 201 overlapping genes between the two datasets, of which 98 were annotated in public databases. These 98 genes displayed distinct expression patterns in C. gigas and C. angulata under heat stress, which were potentially regulated by Clock, indicating its role in a molecular regulatory network that responds to heat stress. Notably, a heat-shock protein 70 family gene (Hsp12b) and a tripartite motif-containing protein (Trim3) were significantly upregulated in C. angulata but showed no significant changes in C. gigas, further highlighting their critical roles in thermal adaptation. This study preliminarily constructs a thermal regulatory network involving Clock, providing insights into the molecular mechanisms of clock genes in thermal adaptation.

Differences in Physiological Characteristics and Heat Shock Protein Expression in Taiwan Swamp Buffaloes During Winter and Summer Seasons

Background: This study examined the respiratory rate, rectal temperature, and expression levels of heat shock protein 70 (HSP70) and heat shock protein 90 (HSP90), as revealed by ELISA, in Taiwan swamp buffaloes (Bubalus bubalis, swamp-type) during the winter (February) and summer (August) seasons of 2022 in Taiwan. Methods: Data were collected from Taiwan swamp buffaloes during the winter and summer seasons. Respiratory rate, rectal temperature, and protein expression levels were measured and analyzed. Results: The results revealed age-related differences in response to changes in environmental temperature. In winter, buffaloes aged <1 year exhibited significantly higher respiratory rates, rectal temperatures, and heat tolerance coefficients than female buffaloes aged 14 to 20 years (P < 0.05). In the summer season, buffaloes aged <1 year had significantly higher rectal temperatures (P < 0.05) and higher expression levels of HSP70 (from ELISA) than female buffaloes aged 6 to 9 years and 14 to 20 years (P < 0.05). Conclusion: The findings suggest that the age of Taiwan swamp buffaloes affects their physiological responses to heat stress, with younger buffaloes exhibiting greater physiological reactions to heat stress than older buffaloes.

Longitudinal single-cell RNA sequencing reveals a heterogeneous response of plasma cells to colonic inflammation.

A comprehensive understanding of the dynamic changes in plasma cells (PCs) during inflammation remains elusive. In this study, we analyzed the distinct responses of PCs across different phases of inflammation in a dextran sodium sulfate (DSS)-induced mouse colitis model. Six-week-old male C57BL/6 mice were treated with 2.2% DSS in distilled water for 5days to induce colitis, and colonic tissues were collected at the peak of inflammation, during recovery, and at the end of the recovery phase. Single-cell RNA sequencing was performed to investigate temporal changes in the gut immune environment. PCs were categorized into six subsets, with Ube2c+PCs displaying notable alterations during various inflammatory phases. Genes such as Pycard, Gpx1, Lgals3, and Chchd10 were significantly expressed in Ube2c+PCs and appeared critical in resolving DSS-induced inflammation. Transcription factors (TFs), including Atf4, Cebpg, Jund, and Klf6, exhibited high regulatory activity in Ube2c+PCs across inflammatory stages. Additionally, we identified an interaction between Chchd10 and C1qbp in PCs, which stabilized C1qbp, reduced reactive oxygen species (ROS) production, and potentially enhanced PC survival and function under inflammatory conditions. This study highlights dynamic quasi-temporal gene expression and TF regulation in PCs during colitis, providing insights for future PC-targeted immunotherapy research.

Terrestrial evidence for volcanogenic sulfate-driven cooling event ~30 kyr before the Cretaceous-Paleogene mass extinction.

Alongside the Chicxulub meteorite impact, Deccan volcanism is considered a primary trigger for the Cretaceous-Paleogene (K-Pg) mass extinction. Models suggest that volcanic outgassing of carbon and sulfur-potent environmental stressors-drove global temperature change, but the relative timing, duration, and magnitude of such change remains uncertain. Here, we use the organic paleothermometer MBT'5me and the carbon-isotope composition of two K-Pg-spanning lignites from the western Unites States, to test models of volcanogenic air temperature change in the ~100 kyr before the mass extinction. Our records show long-term warming of ~3°C, probably driven by Deccan CO2 emissions, and reveal a transient (<10 kyr) ~5°C cooling event, coinciding with the peak of the Poladpur "pulse" of Deccan eruption ~30 kyr before the K-Pg boundary. This cooling was likely caused by the aerosolization of volcanogenic sulfur. Temperatures returned to pre-event values before the mass extinction, suggesting that, from the terrestrial perspective, volcanogenic climate change was not the primary cause of K-Pg extinction.

Design and Experiment of a PLC-Based Intelligent Thermal Insulation Box for Nursing Piglets.

Local heating of the activity area for nursing piglets is crucial for piglet health and the energy efficiency of barn climate control. Traditional heating methods using lamps or covers lack precise control, result in significant energy waste, and cannot be dynamically adjusted according to piglet age or changing environmental temperatures. To address these issues, this study designed a Programmable Logic Controller (PLC)-based thermal insulation box for nursing piglets, utilizing a strip heater instead of the conventional round heating lamp. The design incorporates a movable thermal insulation box that dynamically adjusts the heater's power based on the real-time monitoring of environmental temperatures and target temperatures specific to piglet age. First, in a controlled laboratory environment, the study tested and compared the spatial temperature uniformity, temporal stability, and power consumption of the new thermal insulation box versus traditional heating methods. Subsequently, animal trials were conducted in a farrowing barn using eight sows with similar farrowing dates as test subjects. The new thermal insulation box was installed in one group, and the traditional heating lamp in the control group. During the trial, ambient temperature, insulation area temperature, piglet behavior, growth performance, and power consumption were recorded. The results showed that compared to the control group, the new system reduced average temperature fluctuations in the insulation area by 31.6% and spatial temperature variation by 78.3%. During animal trials, the average temperatures directly under the heater for the new system versus the control in the insulation area were 39.7 ± 0.2 °C and 30.2 ± 1.4 °C in the first week, 40.9 ± 0.5 °C and 31.6 ± 0.7 °C in the second week, and 32.3 ± 1.5 °C and 28.6 ± 1.7 °C in the third week-significantly (p < 0.05) higher in the test group. The new system also reduced total energy consumption by 58.3%. The usage rate of the thermal insulation area by piglets in the test and control groups was 47.5 ± 5.3% and 42.1 ± 6.6%. The daily weight gain of piglets in the test group was 9.8% higher than that of the control group, also significantly (p < 0.05) higher. This intelligent thermal insulation box enables precise and dynamic temperature control, reducing heating energy consumption and supporting improved piglet health and welfare.

Dynamic mechanical analysis of alginate/gellan hydrogels under controlled conditions relevant to environmentally sensitive applications.

Hydrogels are natural/synthetic polymer-based materials with a large percentage of water content, usually above 80%, and are suitable for many application fields such as wearable sensors, biomedicine, cosmetics, agriculture, etc. However, their performance is susceptible to environmental changes in temperature, relative humidity, and mechanical deformation due to their aqueous and soft nature. We investigate the mechanical response of both filled and unfilled alginate/gellan hydrogels using a combined axial-torsional rheometric approach with cylindrical samples of large length/diameter ratio under controlled temperature and relative humidity. Dynamic Mechanical Analysis (DMA) is performed on the same specimen in both torsion and extension under identical experimental conditions. This rheometric approach ensures consistent initial and boundary conditions, which are essential for a reliable estimation of viscoelastic moduli G* and E*, and their dependence on temperature, frequency, and relative humidity. Our findings indicate that humidity critically affects the mechanical response of the material due to sample volume shrinkage, necessitating corrections to the viscoelastic moduli. We also find temperature plays a role only at low/medium relative humidity values. The inclusion of fillers leads to a modest increase in the elasticity of the hydrogel, probably due to restricted water diffusion out of the sample. In connection with the latest, unfilled samples in breaking tests present only slippage due to twist-induced surface water excess, opposite to breakage events shown by filled samples, probably linked to restricted water diffusion.

Predicting adaptation and evolution of plasticity from temporal environmental change

Abstract Environmental change can drive evolutionary adaptation and determine geographic patterns of biodiversity. Yet at a time of rapid environmental change, our ability to predict its evolutionary impacts is incomplete. Temporal environmental change, in particular, involves a combination of major components such as abrupt shift, trend, cyclic change, and noise. Theoretical predictions exist for adaptation to isolated components, but knowledge gaps remain regarding their joint impacts. We extend classic evolutionary theory to develop a model for the evolution of environmental tolerance by the evolution of an underlying developmentally plastic trait, in response to major components of temporal change. We retrieve and synthesise earlier predictions of responses to isolated components, and generate new predictions for components changing simultaneously. Notably, we show how different forms of environmental predictability emerging from the interplay of cyclic change, stochastic change (noise) and lag between development and selection shape predictions. We then illustrate the utility of our model for generating testable predictions for the evolution of adaptation and plasticity when parameterised with real time series data. Specifically, we parameterise our model with daily time series of sea‐surface temperature from a global marine hotspot in southern Australia, and use model simulations to predict the evolution of thermal tolerance, and geographic differences in tolerance, in this region. By synthesising theory on evolutionary adaptation to temporal environmental change, and providing new insights into the joint effects of its different components, our framework, embedded in a Shiny app, offer a path to better predictions of biological responses to climate change.

Thermo-Responsive Polymer-Modified Carbon Nanofiber Electrodes with Autonomous and Heteronomous Switchable Selectivity for Catechol Derivatives

Sophisticated switchable interfaces enable to develop advanced micromachines and biodevices. In the electrochemistry field, functional electrodes switchable by basically either environmental stimuli, such as changes in temperature and pH, or artificial input signals, such as a specific wavelength and magnetic field, have attracted great attention to develop sensors with tunable sensitivity or selectivity and fuel cells with tunable power output in the past few decades. Recently, we have developed thermo- and photo-responsive cup-stacked carbon nanofiber electrodes modified with thermo-responsive poly(N-isopropylacrylamide) (PNIPA/CSCNF electrodes) [1]. PNIPA is known to be reversibly switched between hydrophilic expanded coil structure and hydrophobic collapsed globule structure by environmental temperature changes. CSCNFs have been used as not only electroactive electrode materials but also photothermal conversion materials of near-infrared (NIR) light. Redox species, such as a hydrophilic [Fe(CN)6]3–/4– ion, easily diffused to the CSCNF electrode surface across the swollen PNIPA layer because of its hydrophobic hydration at 25 ˚C without NIR light irradiation, leading to the larger current responses. However, in an electrolyte solution at 45 ˚C and even 25 ˚C with NIR light (> 940 nm) irradiation, the contracted structure of PNIPA was formed because of its hydrophobic interaction, resulting in suppressing transport of the redox species to the CSCNF electrode surface due to its steric hindrance and hydrophobicity. Therefore, the obtained PNIPA/CSCNF electrode allowed to control the activation and inhibition of the electrochemical process for the diffusional redox probe by both alternating surrounding temperature and irradiating the electrode surface with NIR light (Figure 1). If two chemicals with similar structures but different octanol-water partition coefficient log K ow, such as catechol (Mw = 111, Log K ow = 0.88) and dopamine (Mw = 153, Log K ow = –0.98) known as one of the neurotransmitters, contain in the same solution, the present electrode might enable to detect separately. In the present work, we examined autonomous and heteronomous switchable selectivity for catechol and dopamine at the thermo- and photo-responsive PNIPA/CSCNF electrode. As a result, both catechol and dopamine permeated to the CSCNF electrode surface through the swollen PNIPA layer at 25 ˚C, causing their electrochemical signal readout. In contrast, transport of dopamine was selectively suppressed to the CSCNF electrode surface by exposing PNIPA to temperature at 45 ˚C or NIR light irradiation to the CSCNF electrode surface even at 25 ˚C due to the steric hindrance and hydrophobicity of the collapsed globule structure of the PNIPA layer. The electrochemical signal for catechol was therefore observed preferentially. We thus expected that the present electrode would be applied to electrochemical sensors with autonomous and heteronomous switchable selectivity for catechol-based neurotransmitters. [1] K. Komori, R. Ihara, S. Hirao, M. Liu, Y. Toyota, M. Nakata, Y. Tani, and K. Shiraishi, J. Electroanal. Chem., 992, 116704 (2022). Figure 1

Adaptive Control of Multimodal Permanent Magnet Synchronous Motor Based on Embedded Neural Network

Permanent magnet synchronous motors (PMSMs) occupy a core position in various industrial and household equipment due to their excellent energy efficiency, high-power density, and low-noise characteristics. However, facing dynamic factors such as load fluctuations, environmental temperature changes, and manufacturing tolerances, the stability and optimization of its operational efficiency have become a major challenge. To address these issues, this study innovatively proposes a multimodal adaptive control strategy based on embedded neural networks, aiming to enhance the adaptability of PMSM to complex working environments through intelligent learning and optimized decision-making. The core of the research is to construct a control system based on embedded neural networks, which can capture the characteristics of PMSM in different operating modes in real time and learn the corresponding optimal control strategy. The advantages of embedded neural networks lie in their compact model design and efficient computing power, making them highly suitable for resource-constrained motor control systems. Through multimodal learning, the system can recognize and adapt to various states of motor operation, such as start-up, acceleration, steady-state operation, and deceleration, thereby achieving precise control of motor performance.

Study on the impact of humidity on dust dispersion in open-pit mining under different environmental temperatures

To investigate the impact of changes in environmental temperature and humidity on the dust migration patterns during the open-pit mining and loading process, a 1:1 simulation model of open-pit mining and loading was established using SCDM software, based on actual working conditions. Fluent software was used to study the airflow velocity field and dust migration patterns under different temperature and humidity conditions. The simulation results were validated by on-site measurements of dust concentration, with the error values at selected measurement points all within 20%. The results indicate that as relative humidity increases, the dust dispersion capacity decreases, with a more significant reduction in high-temperature environments. Dust concentration is higher in the plane at heights of 3 m to 6 m, and dust tends to accumulate within a range of approximately 10–15 m around the ore transport vehicle. As relative humidity increases from 20% to 80%, the dust concentration within the height range of 3–6 m gradually decreases. At lower environmental temperatures, dust is less likely to settle and tends to move upwards above 6 m. As the environmental temperature increases, dust tends to settle near the ore transport vehicle.

Dual-Responsive PIL Films with Gold Nanoparticles: Tailoring Electrical Responses to pH and Thermal Stimuli.

In recent years, stimuli-responsive poly(ionic liquids) (PILs) have attracted great attention. The stimuli-dependent properties, particularly the electrical properties, of multiresponsive PILs incorporating functionalized nanoparticles, however, have been less investigated. In this work, we present the synthesis, characterization, and application of PIL films incorporating pH- and thermoresponsive hybrid materials composed of gold nanoparticles functionalized with poly(2-(dimethylamino)ethyl methacrylate) (Au@PDMAEMA). The Au@PDMAEMA nanoparticles exhibit distinct responsiveness to changes in environmental pH and temperature, thereby altering the electrical properties of the PIL films blended with responsive gold nanoparticles (PIL w/Au). This research not only fills a gap in the study of electrical properties of multiresponsive nanoparticle-incorporated PILs but also extends the potential applications of PILs in various fields, including smart sensors and electronic devices.

Archival, autonomously-deployed acoustic monitoring systems at the University of New Hampshire

The ocean is continuously changing, and multiple dynamic processes influence the underwater environment over time scales that may vary from minutes to years. As the generation, propagation, and scattering of sound in the ocean is closely tied to the environment, underwater acoustic signals also change over multiple time scales. The Center for Acoustics Research and Education at the University of New Hampshire is developing and deploying autonomous active and passive acoustic sensing platforms to conduct long-term monitoring of the environment in the Gulf of Maine. The platforms are deployed from surface vessels and rest on the seafloor, making measurements at regular intervals. The platforms vary in configuration but contain acoustic sensors (passive hydrophones and active, split-aperture echosounders at multiple frequencies, current profilers) and non-acoustic sensors (cameras, CTDs). This presentation will provide an overview of these platforms, their deployment, operation, and applications of the data to understand temporal changes in the underwater environment.

Nanofluidic Thermoelectric Transducer with Ultrahigh and Tunable Sensitivity.

Thermosensitive transient receptor potential (thermoTRP) ion channels can transduce external thermal stimuli to neural electrical signals, allowing organisms to detect and respond to changes in environmental temperature. Reproducing such ionic machinery holds promise for advancing the design of highly efficient low-grade thermal energy harvesters and ultrasensitive thermal sensors. However, there still exist challenges for artificial nanofluidic architectures to achieve comparable thermoelectric performance. Here, we report nanofluidic thermoelectric transducers with ultrahigh and tunable sensitivities controlled by electrostatic gating in graphene nanochannels. The equivalent Seebeck coefficient can be significantly boosted and reaches 1 order of magnitude higher than the current state of the art, even beyond thermoTRP ion channels. The improvement is attributed to substantial slippage on the highly charged graphene surface, leading to enhanced electrokinetic ion transport inside the graphene channel, which is confirmed by a scaling theory for thermoelectric coupling as well as molecular dynamic simulations. The dependence of the nanofluidic thermoelectric on the concentration, channel size, and cation types is also investigated to further clarify the underlying mechanism.

Cooperative Control of Bioelectrocatalytic Activity for Thermo- and Photo-Switchable Cup-Stacked Carbon Nanofiber Electrodes Modified with Phase Transition Polymer and Heme Peptide.

Empowering biocatalyst-modified electrodes with the ability to both enforce and perceive will enable the development of intrinsically switchable bioelectrode systems, which exhibit autonomous and heteronomous actions specific to living organisms. However, the electrocatalytic activity of switchable bioelectrodes reported so far has been controlled by changes in the rate of substrate transport to biocatalysts. Here, we prepared a cup-stacked carbon nanofiber (CSCNF) electrode modified with a thermoresponsive N-isopropylacrylamide-based polymer containing peroxidase model compounds (HP). As CSCNFs worked as a converter from near-infrared (NIR) light to heat, bioelectrocatalytic activity of the electrode to H2O2 reduction was reversibly controlled by changes in the amount of electroactive HP, based on expanded and contracted states of the polymers induced by not only environmental temperature changes but also external NIR light irradiation. This intrinsically switchable bioelectrode technique would hold promise for adding new performances in electrochemical biosensors and biofuel cells, for example, autonomous and heteronomous tunable sensitivity and capacity.

Magnetic Torque-Driven All-Terrain Microrobots.

All-terrain microrobots possess significant potential in modern medical applications due to their superior maneuverability in complex terrains and confined spaces. However, conventional microrobots often struggle with adaptability and operational difficulties in variable environments. This study introduces a magnetic torque-driven all-terrain multiped microrobot (MTMR) to address these challenges. By coupling the structure's multiple symmetries with different uniform magnetic fields, such as rotating and oscillating fields, the MTMR demonstrates various locomotion modes, including rolling, tumbling, walking, jumping, and their combinations. Experimental results indicate that the robot can navigate diverse terrains, including flat surfaces, steep slopes (up to 75°), and gaps over twice its body height. Additionally, the MTMR performs well in confined spaces, capable of passing through slits (0.1 body length) and low tunnels (0.25 body length). The robot shows potential for clinical applications like minimally invasive hemostasis in internal bleeding and thrombus removal from blood vessels through accurate cargo manipulation capability. Moreover, the MTMR can carry temperature sensors to monitor environmental temperature changes in real time while simultaneously manipulating objects, displaying its potential for in-situ sensing and parallel task implementation. This all-terrain microrobot technology demonstrates notable adaptability and versatility, providing a solid foundation for practical applications in interventional medicine.

Individual methanogenic granules are whole-ecosystem replicates with reproducible responses to environmental cues

BackgroundIn this study, individual methanogenic (anaerobic), granular biofilms were used as true community replicates to assess whole-microbial-community responses to environmental cues. The aggregates were sourced from a lab-scale, engineered, biological wastewater treatment system, were size-separated, and the largest granules were individually subjected to controlled environmental cues in micro-batch reactors (μBRs).ResultsIndividual granules were identical with respect to the structure of the active community based on cDNA analysis. Additionally, it was observed that the active microbial community of individual granules, at the depth of 16S rRNA gene sequencing, produced reproducible responses to environmental changes in pH, temperature, substrate, and trace-metal supplementation. We identified resilient and susceptible taxa associated with each environmental condition tested, as well as selected specialists, whose niche preferences span the entire trophic chain required for the complete anaerobic degradation of organic matter.ConclusionsWe found that single anaerobic granules can be considered highly-replicated whole-ecosystems with potential usefulness for the field of microbial ecology. Additionally, they act as the smallest whole-community unit within the meta-community of an engineered bioreactor. When subjected to various environmental cues, anaerobic granules responded reproducibly allowing for rare or unique opportunities for high-throughput studies testing whole-community responses to a wide range of environmental conditions.

Research on the oxidation process of micro-boron below the melting point temperature

The ignition and combustion characteristics of boron and the energy release rate of boron-based fuel are closely related to the surface oxide layer of boron. To understand the oxidation process of boron below its melting point, the slow oxidation process of boron under different temperature and humidity storage conditions and the fast oxidation process under high-temperature conditions were investigated. The results indicate that the surface oxide layer mainly comprises boron (B), boron suboxides (BxOy), and boron trioxide (B2O3). When the degree of oxidation is low, BxOy and B are the main components. After deep oxidation, BxOy almost disappeared. The thickness and composition of the surface oxide layer vary with changes in environmental temperature, humidity, and aging time. The effect of temperature increase on the growth rate of the oxide layer thickness is significantly greater than that of moisture. With the prolongation of boron aging treatment time, the onset, end, and maximum weight gain rate temperatures of the boron thermal oxidation process all slightly decrease. As the ambient temperature increases, the formation of the oxide layer transitions from a unidirectional diffusion mechanism of oxygen into the interior of boron particles to a bidirectional diffusion mechanism of molten oxide and oxygen.

Temperature change regulates pollen fertility of a PTGMS rice line PA64S by modulating the ROS homeostasis and PCD within the tapetum.

Photoperiod and temperature-sensitive male sterility rice is an important line for two-line hybrid rice, and the changes in the cultivation temperature strictly control its pollen fertility. However, the mechanism by which temperature variation regulates pollen fertility is still unclear. This study obtained stable fertile PA64S(F) and sterile PA64S(S) rice from PA64S by controlling temperature changes. PA64S(F) shows a normal anther development and fertile pollen under low temperature (21°C), and PA64S(S) shows delayed degradation of the tapetum cells, leading to abnormal pollen wall formation and ubisch development under normal temperature (28°C). The accumulation of reactive oxygen species (ROS) positively correlates with the programmed cell death (PCD) process of tapetum cells. The delayed accumulation of ROS in the PA64S(S) tapetum at early stages leads to a delayed initiation of the PCD process. Importantly, we localized ascorbic acid (ASA) accumulation in the tapetum cells and determined that ASA is a major antioxidant for ROS homeostasis. ROS-inhibited accumulation plants (PA64S-ASA) demonstrated pollen sterility, higher ASA and lower ROS accumulation in the tapetum, and the absence of PCD processes in the tapetum cell. Abnormal changes in the tapetum of PA64S(S) rice disrupted metabolic pathways such as lipid metabolism, cutin and wax synthesis, sugar accumulation, and phenylpropane, affecting pollen wall formation and substance accumulation, suggesting that the timely accumulation of ROS is critical for male fertility. This study highlights the central role of ROS homeostasis in fertility alteration and also provides an avenue to address the effect of environmental temperature changes on pollen fertility in rice.

Zero-power infrared switch with two-phase microfluidic flow and a 2D material thermal isolation layer

Wireless sensor nodes (WSNs) play an important role in many fields, including environmental monitoring. However, unattended WSNs face challenges in consuming power continuously even in the absence of useful information, which makes energy supply the bottleneck of WSNs. Here, we realized zero-power infrared switches, which consist of a metasurface and two-phase microfluidic flow. The metasurface can recognize the infrared signal from the target and convert it into heat, which triggers the two-phase microfluidic flow switch. As the target is not present, the switch is turned off. The graphene/MoS2/graphene 2D material heterostructure (thickness <2 nm) demonstrates an exceptionally high thermal resistance of 4.2 K/W due to strong phonon scattering and reduces the heat flow from the metasurface to the supporting substrate, significantly increasing the device sensitivity (the displacement of the two-phase microfluidic flow increases from ~1500 to ~3000 µm). The infrared switch with a pair of symmetric two-phase microfluidic flows can avoid spurious triggering resulting from environmental temperature changes. We realized WSNs with near-zero standby power consumption by integrating the infrared switch, sensors, and wireless communication module. When the target infrared signal appears, the WSNs are woken and show superb visual/auditory sensing performance. This work provides a novel approach for greatly lengthening the lifespan of unattended WSNs.

Low-loss and low-temperature sintering of SrNb2V2O11 with a large positive τf value as an effective temperature compensator

Novel SrNb2V2O11 microwave dielectric was synthesized and proposed as a temperature compensator for Low-temperature cofired ceramics (LTCC)/Ultra-low-temperature cofired ceramics (ULTCC) applications. The X-ray diffractometer (XRD) patterns matched well with the SrNb2V2O11 phase, exhibiting a monoclinic structure and Cc space group over the entire experiment. The presence of the Nb-rich second phase at 850 °C was attributed to the melting of the samples. The microwave dielectric properties were highly correlated with the chemical bond parameters, which were intensively investigated using the P-V-L theory. The specimen sintered at 820 °C reveals dielectric properties, combining an εr of 74.5, Q × f of 13,000 GHz, and τf of 517 ppm/°C. The large positive τf can make the ceramic an effective temperature compensator for LTCC applications. Moreover, the medium-high εr value can also act as a practical material for dielectric resonators used in the base stations, where a stable environment and limited temperature changes are crucial.