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In optical imaging of solid tumors, signal contrasts derived from inherent tissue temperature differences have been employed to distinguish tumor masses from surrounding tissue. Moreover, with the advancement of active infrared imaging, dynamic thermal characteristics in response to exogenous thermal modulation (heating and cooling) have been proposed as novel measures of tumor assessment. Contrast factors such as the average rate of temperature changes and thermal recovery time constants have been investigated through an active thermal modulation imaging approach, yielding promising tumor characterization results in a xenograft mouse model. Here, to assess its clinical potential, we developed and deployed an endoscopic infrared thermal modulation imaging system, incorporating anti-reflection germanium lenses. Employing tissue cooling, we evaluated the feasibility of detecting in situ tumors in a syngeneic rectal tumor mouse model. Consequently, early-stage tumors were successfully localized and evaluated based on their heat signatures. Notably, tumors exhibited a higher rate of temperature change induced by thermal modulation compared to adjacent tissues. Through the introduction of this label-free technology, Infrared Thermal Modulation Endoscopy (ITME), our study showcased an effective method for optically delineating and assessing solid tumors. This innovative diagnostic technology holds significant promise for enhancing our ability to detect, classify, and characterize abnormal tissues., Competing Interests: Declarations. Competing interests: The authors declare no competing interests. Supplementary information: See Supplement file 1 for supporting content., (© 2025. The Author(s).)

This article presents the development of an artificial olfactory bulb (OB) using an electronic nose with thermally modulated metal-oxide sensors. Inspired by animal OBs, our approach employs thermal modulation to replicate the spatial encoding patterns of glomeruli clusters and subclusters. This new approach enhances the classification capabilities of traditional electronic noses and offers new insights for biomimetic olfaction. Molecular receptive range (MRR) analysis confirms that our artificial OB effectively mimics the glomerular distribution of animal OBs. Additionally, the incorporation of a short axon cell (SAC) network, inspired by the animal olfactory system, significantly improves lifetime sparseness and qualitative ability of the artificial OB through extensive lateral inhibition, providing a theoretical framework for enhanced olfactory performance., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Acting like thermal resistances, ferroelectric domain walls can be manipulated to realize dynamic modulation of thermal conductivity (k), which is essential for developing novel phononic circuits. Despite the interest, little attention has been paid to achieving room-temperature thermal modulation in bulk materials due to challenges in obtaining a high thermal conductivity switching ratio (k high /k low ), particularly in commercially viable materials. Here, room-temperature thermal modulation in 2.5 mm-thick Pb(Mg 1/3 Nb 2/3 )O 3 -xPbTiO 3 (PMN-xPT) single crystals is demonstrated. With the use of advanced poling conditions, assisted by the systematic study on composition and orientation dependence of PMN-xPT, a range of thermal conductivity switching ratios with a maximum of ≈1.27 is observed. Simultaneous measurements of piezoelectric coefficient (d 33 ) to characterize the poling state, domain wall density using polarized light microscopy (PLM), and birefringence change using quantitative PLM reveal that compared to the unpoled state, the domain wall density at intermediate poling states (0< d 33 33,max ) is lower due to the enlargement in domain size. At optimized poling conditions (d 33,max ), the domain sizes show increased inhomogeneity that leads to enhancement in the domain wall density. This work highlights the potential of commercially available PMN-xPT single crystals among other relaxor-ferroelectrics for achieving temperature control in solid-state devices., (© 2023 The Authors. Advanced Materials published by Wiley-VCH GmbH.)

This review article highlights the historical developments and current state of knowledge of an important neuromodulation technology: low-intensity focused ultrasound. Because compelling studies have shown that focused ultrasound can modulate neuronal activity non-invasively, especially in deep brain structures with high spatial specificity, there has been a renewed interest in attempting to understand the specific bioeffects of focused ultrasound at the cellular level. Such information is needed to facilitate the safe and effective use of focused ultrasound to treat a number of brain and nervous system disorders in humans. Unfortunately, to date, there appears to be no singular biological mechanism to account for the actions of focused ultrasound, and it is becoming increasingly clear that different types of nerve cells will respond to focused ultrasound differentially based on the complement of their ion channels, other membrane biophysical properties, and arrangement of synaptic connections. Furthermore, neurons are apparently not equally susceptible to the mechanical, thermal and cavitation-related consequences of focused ultrasound application-to complicate matters further, many studies often use distinctly different focused ultrasound stimulus parameters to achieve a reliable response in neural activity. In this review, we consider the benefits of studying more experimentally tractable invertebrate preparations, with an emphasis on the medicinal leech, where neurons can be studied as unique individual cells and be synaptically isolated from the indirect effects of focused ultrasound stimulation on mechanosensitive afferents. In the leech, we have concluded that heat is the primary effector of focused ultrasound neuromodulation, especially on motoneurons in which we observed a focused ultrasound-mediated blockade of action potentials. We discuss that the mechanical bioeffects of focused ultrasound, which are frequently described in the literature, are less reliably achieved as compared to thermal ones, and that observations ascribed to mechanical responses may be confounded by activation of synaptically-coupled sensory structures or artifacts associated with electrode resonance. Ultimately, both the mechanical and thermal components of focused ultrasound have significant potential to contribute to the sculpting of specific neural outcomes. Because focused ultrasound can generate significant modulation at a temperature <5°C, which is believed to be safe for moderate durations, we support the idea that focused ultrasound should be considered as a thermal neuromodulation technology for clinical use, especially targeting neural pathways in the peripheral nervous system., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Collins and Mesce.)

All-solid-state batteries (ASSBs) show great potential as high-energy and high-power energy-storage devices but their attainable energy/power density at room temperature is severely reduced because of the sluggish kinetics of lithium-ion transport. Here a thermally modulated current collector (TMCC) is reported, which can rapidly cold-start ASSBs from room temperature to operating temperatures (70-90 °C) in less than 1 min, and simultaneously enhance the transient peak power density by 15-fold compared to one without heating. This TMCC is prepared by integrating a uniform, ultrathin (≈200 nm) nickel layer as a thermal modulator within an ultralight polymer-based current collector. By isolating the thermal modulator from the ion/electron pathway of ASSBs, it can provide fast, stable heat control yet does not interfere with regular battery operation. Moreover, this ultrathin (13.2 µm) TMCC effectively shortens the heat-transfer pathway, minimizes heat losses, and mitigates the formation of local hot spots. The simulated heating energy consumption can be as low as ≈3.94% of the total battery energy. This TMCC design with good tunability opens new frontiers toward smart energy-storage devices in the future from the current collector perspective., (© 2022 Wiley-VCH GmbH.)

Many materials used in a wide range of fields consist of polymers that feature great structural complexity. One particularly suitable technique for characterising these complex polymers, that often feature correlated distributions in e.g. microstructure, chemical composition, or molecular weight, is comprehensive two-dimensional liquid chromatography (LC × LC). For example, using a combination of reversed-phase LC and size-exclusion chromatography (RPLC × SEC). Efficient and sensitive LC × LC often requires focusing of the analytes between the two stages. For the analysis of large-molecule analytes, such as synthetic polymers, thermal modulation (or cold trapping) may be feasible. This approach is studied for the analysis of a styrene/butadiene "star" block copolymer. Trapping efficiency is evaluated qualitatively by monitoring the effluent of the trap with an evaporative light-scattering detector and quantitatively by determining the recovery of polystyrene standards from RPLC × SEC experiments. The recovery was dependant on the molecular weight and the temperatures of the first-dimension column and of the trap, and ranged from 46% for a molecular weight of 2.78 kDa to 86% (or up to 94.5% using an optimized set-up) for a molecular weight of 29.15 kDa, all at a first-dimension-column temperature of 80 °C and a trap temperature of 5 °C. Additionally a strategy to reduce the pressure pulse from the modulation has been developed, bringing it down from several tens of bars to only a few bar., Competing Interests: Declaration of Competing Interest All authors declare no conflicts of interests., (Copyright © 2021. Published by Elsevier B.V.)

The solid-state-modulator is a consumable-free thermal modulator, used within the context of comprehensive two-dimensional gas chromatography. Its consumable-free nature is guaranteed by the presence of a thermal-electric cooler device located between two heated chambers, everything located outside the gas chrpmatograph oven. The aim of the present research is to evaluate the solid-state-modulator modulation performance in relationship to different modulation capillary geometries. For this purpose, two coated modulation capillaries with the same length, but with different internal diameters (0.25 and 0.18 mm) were used. The effects of gas linear velocity, modulator temperature, and modulation period were evaluated in several applications involving standard alkanes and a sample of diesel fuel. Fundamental gas chromatography parameters (peaks widths, resolution) were measured under the different experimental conditions. Detailed information is provided on gas flow optimization, with particular emphasis on the efficiency of chromatography band reinjection onto the second-dimension column. The results obtained from the present investigation highlight how the modulation capillary characteristics have a great impact on the overall comprehensive two-dimensional gas chromatography separation. Specifically, considering the results herein attained, the use of a 0.18 mm ID × 0.18 μm d f modulation column is advisable compared to a 0.25 mm ID × 0.25 μm d f one., (© 2021 Wiley-VCH GmbH.)

The applications of metal-organic frameworks (MOFs) as sulfur hosts focus on pristine MOFs and their carbonization products for establishing high-performance lithium-sulfur batteries (LSBs). However, the mechanism that modulates the specific nanostructures and the compositions at different treatment temperatures still needs further exploration. In this work, we modulate the pyrolysis products of UiO-66-NH 2 @rGO (U@rGO) at a predetermined specific temperature by thermogravimetric (TG) analysis and systematically investigate their microstructure and chemical characteristic evolution. The composite processed at 300 °C (U@rGO-P300) results in the rearrangement of an octahedral nanophase into an amorphous material while retaining a large number of functional groups of -NH 2 and COO-, which lead to an additional nanostructure interface and a high Brunauer-Emmett-Teller (BET) surface area of 298.4 m 2 g -1 . Moreover, the newly created abundant suboxidative Zr 3+ atom sites serve as the polysulfide anchor and transfer mediator active sites. The assembled LSBs could deliver a capacity of 906.1 and retain 801.7 mA h g -1 after 300 cycles at 1C with a low fading rate of around 0.05% per cycle and an improved rate performance of 619.1 mA h g -1 at 4C. The Li + diffusion coefficients are significantly increased by 10-60 times. This work provides a simple route to activate the metal sites in the MOF category with a suboxidative state, leading to intriguing and unanticipated properties.

A new signal processing technique has been developed for resistive metal oxide (MOX) gas sensors to enable high-bandwidth measurements and enhanced selectivity at PPM levels (<5 PPM VOCs). An embedded micro-heater is thermally pulsed from a temperature of 225 to 350 °C, which enables the chemical reaction kinetics of the sensing film to be extracted using a fast Fourier transform. Signal processing is performed in real-time using a low-cost microcontroller integrated into a sensor module. Three sensors, coated with SnO₂, WO₃ and NiO respectively, were operated and processed at the same time. This approach enables the removal of long-term baseline drift and is more resilient to changes in ambient temperature. It also greatly reduced the measurement time from ~10 s to 2 s or less. Bench-top experimental results are presented for 0 to 200 ppm of acetone, and 0 ppm to 500 ppm of ethanol. Our results demonstrate our sensor system can be used on a mobile robot for real-time gas sensing.

The present research is based on the use of a recently developed comprehensive two-dimensional gas chromatography thermal modulator, which is defined as solid-state modulator. The transfer device was installed on top of a single gas chromatography oven, while benchtop low-resolution time-of-flight mass spectrometry was used to monitor the compounds exiting the second analytical column. The solid-state modulator was first described by Luong et al. in 2016, and it is a moving modulator that does not require heating and cooling gases to generate comprehensive two-dimensional gas chromatography data. The accumulation and remobilization steps occur on a trapping capillary, this being subjected to thermoelectric cooling and micathermic heating. In this study, the effects of the gas linear velocity on the modulation performance were evaluated by using two different uncoated trapping capillaries, viz., 0.8 m × 0.25 mm id and 0.8 m × 0.20 mm id. Solid-state modulator applications were carried out on a standard solution containing n-alkanes (C 9, C 10, C 12 ), and on a sample of diesel fuel. The results indicated that the type of trapping capillary and gas velocity have a profound effect on modulation efficiency., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The volatile composition of honeybush (Cyclopia) species was studied by comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC×GC-TOF-MS). Headspace-solid phase micro-extraction (HS-SPME) was used to extract the volatile compounds from tea infusions prepared from the three species C. genistoides, C. maculata and C. subternata. A total of 287 compounds were identified, 101 of which were confirmed using reference standards, while the remainder were tentatively identified using mass spectral and retention index (RI) data. The identification power of TOF-MS enabled the tentative identification of 147 compounds for the first time in honeybush tea. The majority of the compounds identified were common to all three Cyclopia species, although there were differences in their relative abundances, and some compounds were unique to each of the species. In C. genistoides, C. maculata and C. subternata 265, 257 and 238 compounds were identified, respectively. Noteworthy was the tentative identification of cinnamaldehyde in particular C. maculata samples, which points to the likely contribution of this compound to their distinct sensory profiles. This study emphasises the complexity of honeybush tea volatile composition and confirms the power of GC×GC combined with TOF-MS for the analysis of such complex samples., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The applicability of comprehensive two-dimensional gas chromatography (GC×GC) using a single-stage thermal modulator was explored for the analysis of honeybush tea (Cyclopia spp.) volatile compounds. Headspace solid phase micro-extraction (HS-SPME) was used in combination with GC×GC separation on a non-polar × polar column set with flame ionisation (FID) detection for the analysis of fermented Cyclopia maculata, Cyclopia subternata and Cyclopia genistoides tea infusions of a single harvest season. Method optimisation entailed evaluation of the effects of several experimental parameters on the performance of the modulator, the choice of columns in both dimensions, as well as the HS-SPME extraction fibre. Eighty-four volatile compounds were identified by co-injection of reference standards. Principal component analysis (PCA) showed clear differentiation between the species based on their volatile profiles. Due to the highly reproducible separations obtained using the single-stage thermal modulator, multivariate data analysis was simplified. The results demonstrate both the complexity of honeybush volatile profiles and the potential of GC×GC separation in combination with suitable data analysis techniques for the investigation of the relationship between sensory properties and volatile composition of these products. The developed method therefore offers a fast and inexpensive methodology for the profiling of honeybush tea volatiles. Graphical abstract Surface plot obtained for the GC×GC-FID analysis of honeybush tea volatiles.

Photodynamic therapy (PDT) is a noninvasive and effective approach for cancer treatment. The main bottlenecks of clinical PDT are poor selectivity of photosensitizer and inadequate oxygen supply resulting in serious side effects and low therapeutic efficiency. Herein, a thermal-modulated reactive oxygen species (ROS) strategy using activatable human serum albumin-chlorin e6 nanoassemblies (HSA-Ce6 NAs) for promoting PDT against cancer is developed. Through intermolecular disulfide bond crosslinking and hydrophobic interaction, Ce6 photosensitizer is effectively loaded into the HSA NAs, and the obtained HSA-Ce6 NAs exhibit excellent reduction response, as well as enhanced tumor accumulation and retention. By the precision control of the overall body temperature instead of local tumor temperature increasing from 37 °C to 43 °C, the photosensitization reaction rate of HSA-Ce6 NAs increases 20%, and the oxygen saturation of tumor tissue raise 52%, significantly enhancing the generation of ROS for promoting PDT. Meanwhile, the intrinsic fluorescence and photoacoustic properties, and the chelating characteristic of porphyrin ring can endow the HSA-Ce6 NAs with fluorescence, photoacoustic and magnetic resonance triple-modal imaging functions. Upon irradiation of low-energy near-infrared laser, the tumors are completely suppressed without tumor recurrence and therapy-induced side effects. The robust thermal-modulated ROS strategy combined with albumin-based activatable nanophotosensitizer is highly potential for multi-modal imaging-guided PDT and clinical translation., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Stochastic resonance is a mechanism whereby a weak signal becomes detectable through the addition of noise. It is common in many macroscopic biological phenomena, but here we ask whether it can be observed in a microscopic biological phenomenon, protein folding. We investigate the folding kinetics of the protein VlsE, with a folding relaxation time of about 0.7 seconds at 38 °C in vitro. First we show that the VlsE unfolding/refolding reaction can be driven by a periodic thermal excitation above the reaction threshold. We detect the reaction by fluorescence from FRET labels on VlSE and show that accurate rate coefficients and activation barriers can be obtained from modulated kinetics. Then we weaken the periodic temperature modulation below the reaction threshold, and show that addition of artificial thermal noise speeds up the reaction from an undetectable to a detectable rate. We observe a maximum in the recovered signal as a function of thermal noise, a stochastic resonance. Simulation of a small model-protein, analysis in an accompanying theory paper, and our experimental result here all show that correlated noise is a physically and chemically plausible mechanism by which cells could modulate biomolecular dynamics during threshold processes such as signaling., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Comprehensive two-dimensional gas chromatography (GC×GC) with a temperature-programmed microfabricated thermal modulator (μTM) is demonstrated. The 0.78 cm(2), 2-stage μTM chip with integrated heaters and a PDMS coated microchannel was placed in thermal contact with a solid-state thermoelectric cooler and mounted on top of a bench scale GC. It was fluidically coupled through heated interconnects to an upstream first-dimension ((1)D) PDMS-coated capillary column and a downstream uncoated capillary or second-dimension ((2)D) PEG-coated capillary. A mixture of n-alkanes C6-C10 was separated isothermally and the full-width-at-half-maximum (fwhm) values of the modulated peaks were assessed as a function of the computer-controlled minimum and maximum stage temperatures of μTM, Tmin and Tmax, respectively. With Tmin and Tmax fixed at -25 and 100°C, respectively, modulated peaks of C6 and C7 had fwhm values<53 ms while the modulated peaks of C10 had a fwhm value of 1.3s, due to inefficient re-mobilization. With Tmin and Tmax fixed at 0 and 210°C, respectively, the fwhm value for the modulated C10 peaks decreased to 67 ms, but C6 and C7 exhibited massive breakthrough. By programming Tmin from -25 to 0°C and Tmax from 100 to 220°C, the C6 and C7 peaks had fwhm values≤50 ms, and the fwhm for C10 peaks remained<95 ms. Using the latter conditions for the GC×GC separation of a sample of unleaded gasoline yielded resolution similar to that reported with a commercial thermal modulator. Replacing the PDMS phase in the μTM with a trigonal-tricationic room temperature ionic liquid eliminated the bleed observed with the PDMS, but also reduced the capacity for several test compounds. Regardless, the demonstrated capability to independently temperature program this low resource μTM enhances its versatility and its promise for use in bench-scale GC×GC systems., (Copyright © 2016 Elsevier B.V. All rights reserved.)