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Plants emit volatile organic compounds (VOCs) into the atmosphere, reaching approximately 109 tons of carbon per year. These biogenic VOCs exhibit significant chemical diversity, with terpenoids being the dominant group, and isoprene accounting for nearly half of the total biogenic VOCs. Due to its high chemical reactivity, isoprene has a strong impact on atmospheric quality and climate. Quercus (Fagaceae) species are the main isoprene emitters in the Northern Hemisphere. However, isoprene synthase has not been identified in the entire Fagaceae family. Even within a single genus such as Quercus, both isoprene-emitting and non-emitting species coexist, yet the molecular basis of this dichotomy remains unclear. Here, we report the identification of the IspS gene from the isoprene-emitting species Quercus serrata (QsIspS1) through seasonal transcriptome analysis and detailed biochemical characterization of the gene product. We also identified two genes with high sequence similarity to QsIspS1 in the genomes of non-emitting species: Q. glauca (QgIspS1-like) and Lithocarpus edulis (LeIspS1-like). We discovered mutations in these sequences that likely impair their function. Biochemical analysis revealed that QgIspS1-like is a monoterpene synthase, whereas LeIspS1-like is a pseudogene incapable of isoprene synthesis, explaining these plants' inability to emit isoprene. Furthermore, site-directed mutagenesis revealed an amino acid that plays a pivotal role in the substrate and product specificities of isoprene synthase. Our findings provide insight into the molecular mechanisms underlying isoprene emission diversity in Fagaceae.

Plants continuously emit volatile organic compounds (VOCs), which can influence the physiology and behavior of neighboring plants. While the ecological role of stress-induced VOCs is well established, the function of constitutive VOCs released by undamaged plants in mediating plant-plant interactions remains less understood. Here, we demonstrate that barley plants can detect the growth rate of undamaged conspecific neighbors through constitutive VOCs and respond by modulating their growth-defense trade-off accordingly. Exposure to volatiles from cultivars with contrasting growth (slow or fast) triggered distinct shifts in biomass accumulation and gene expression in receiver plants, whereas VOCs from cultivars with similar growth rates had negligible effects. Transcriptomic analysis revealed cultivar-specific transcriptional reprogramming of growth- and defense-related pathways, suggesting that constitutive VOCs convey information about emitter identity and competitive vigour that receiver plants use to adaptively reallocate resources and prime stress responses in anticipation of competition. These findings uncover a previously unrecognized role of constitutive VOCs as reliable cues of emitter identity and vigor, mediating adaptive responses in neighboring plants under competitive scenarios.

Previous studies using solvatochromic dyes as probes of diluted and succussed solutions have indicated that potencies produce an electric field and are also nullified by having a weak electric current passed through them. The objectives of the current study were to build and expand on these observations. In particular, it has been proposed that if potencies produce their own electric field, this is likely due to the presence of separated charges. On application of an electrical current these charges are predicted to recombine and in so doing emit light. A specially adapted single tube luminometer has been used to monitor photon emissions from potency solutions of Arsenicum album 10M (Ars 10M) and controls, using fluorescein to extend the detection range of the instrument. A sharp photon emission peak is detectable from solutions of Ars 10M on application of a 9v/18mA electric current. Potency solutions only show the peak on application of the electric current and control solutions show no peak. The presence of 10 µM fluorescein is necessary in order to see the emission peak. Calculations show the charge-pair concentration in solution is 10-14M, assuming one photon is emitted per charge-pair. For Ars 10M that has been subjected to an electric current, photon emission and loss of activity against the solvatochromic dye DMABR correlate. The sharp photon emission peak seen in solutions of Ars 10M, but not in control solutions, requires fluorescein to be present and indicates the photons emitted are in the ultraviolet range. The concentration of separate charge-pairs, calculated from the photon emission level, is approximately 10-14M. Their identity remains unknown at this time, but they appear to be responsible for the activity of Ars 10M, as determined by its action against DMABR, and by extrapolation its clinical activity.

Vocal sound production has been reported in juveniles of mammalian, avian, and nonavian sauropsid lineages. In this last taxon, studies concerning the ontogenetic development of vocalizations have mainly been focused on Crocodylia and Testudines. Less is known about Squamata, though this behavior has been recognized in a few juvenile gecko species, albeit only characterized in the Mediterranean House Gecko (Hemidactylus turcicus). In the present study, we identified the vocalizations emitted by the juvenile Balsas Basin Whiptail lizard (Aspidoscelis costatus costatus), a species endemic to Mexico. We sought to characterize the spectro-temporal variables of the juveniles' calls and determine whether these vocalizations occur during early ontogeny or are associated with a minimum snout-vent length. The study included 74 individuals (41 hatchlings, 33 juveniles); only 21 juveniles vocalized (16 females and 5 males). The calls possessed simple and complex modulation patterns and were only emitted when the individuals were seized. Thus, we classified them as distress calls. Sound production occurs before the first year of life. However, hatchlings did not vocalize, and individuals required a minimum snout-vent length to emit sound. Three nonmutually exclusive hypotheses are proposed to interpret these findings: 1) the vocal structure responsible for sound production develops during ontogeny; 2) juveniles do not have enough energy to vocalize, as this energy is primarily allocated for growth and maturation; and 3) juveniles only vocalize once an adequate size has been obtained, which allows calls to reach an effective intensity and/or duration.

Alpha-emitting radionuclides enable precise cancer therapy through high linear energy transfer and limited tissue penetration, damaging tumor cells while sparing healthy tissue. Diffusing Alpha-emitters Radiation Therapy (Alpha DaRT) features Ra-224 sources that are implanted directly into the tumor and emit alpha particles during radioactive decay. Alpha DaRT has demonstrated efficacy and safety in preclinical and early clinical trials across multiple tumor types, including skin, head and neck, and pancreatic cancers. Reliable and efficient methods for verifying Alpha DaRT source activity prior to treatment can help support accurate and consistent radiation delivery. The direct measurement of alpha particles from sources within an Alpha DaRT applicator is impractical due to their short range; however, gamma emissions from the Ra-224 sources can be used to infer radioactivity. This study established a protocol for verifying the source activity within Ra-224 Alpha DaRT applicators using a reentrant well-type ionization chamber, providing users with a practical method for detecting errors in source manufacturing or certificate paperwork without compromising applicator sterility. Ra-224 Alpha DaRT sources in sterile packaging (Flex and Needle applicators with 1-4 sources) were assessed. Source energy spectra and activities were verified using a high-purity germanium (HPGe) radiation detector. Calibration factors (kBq/pA) were established using an IVB1000 well-type ionization chamber with measurements conducted by placing single applicator sterile packages into the chamber with sources centered in the chamber's sweet spot and corrected for temperature, pressure, and leakage current. Quality assurance was performed on 26 Flex applicators using the established calibrations before the first clinical procedure. HPGe measurements agreed with vendor-stated activities. The average calibration coefficient using the IVB1000 chamber was 233 ± 3 kBq/pA for Flex and 597 ± 7 kBq/pA for Needle applicators. Calibration coefficients were consistent across two IVB1000 chambers. Source number dependence was observed, with calibration factors increasing by 1.7% ± 0.7% per source (Needle) and 2.7% ± 0.6% per source (Flex). Measurement repeatability was 3.3%. Applying the calibration to 26 Flex applicators before the first patient treatment yielded a 1.1 ± 5.8% (range: -7.5% to 11.4%) difference relative to the vendor's stated activity. A reentrant well-type ionization chamber is suitable for pre-treatment quality assurance of Ra-224 Alpha DaRT applicators, enabling verification of the vendor-stated activity while maintaining sterility within sealed packaging.

In this Letter, we report on the demonstration of InGaN/AlGaN nanowire red light-emitting diodes, which exhibit high thermal robustness under extreme operating conditions. The devices emit at a wavelength of ~650 nm and maintain stable red electroluminescence over injection currents from 10 to 1000 mA. Temperature-dependent electroluminescence characterization reveals sustained emission from 25 °C to ~950 °C under ramped conditions with a minimal peak wavelength shift of ~3-5 nm and moderate spectral broadening of ~10 nm. The emission linewidth remains broad, with a full width at half maximum of ~94 nm across the entire temperature range. These results establish III-nitride nanowire LEDs as a robust platform for high-temperature red emission, with implications for optoelectronic systems operating in harsh environments, including aerospace, high-temperature industrial processes, and advanced sensing.

The ovarian follicles of Gymnocephalus cernua consist of a single oocyte surrounded by follicular cells (FCs), a basal lamina and thecal cells. To address the lack of knowledge regarding the early development of oocytes, the early, mid-, and late previtellogenic follicles were examined. The oocytes are polarized. In early previtellogenic oocytes the nuclei are eccentrically located and emit nuage to the cytoplasm (ooplasm), in close proximity to the follicular epithelium in the animal region. There, a micropylar cell responsible for the formation of the micropylar canal in the egg envelopes is determined. The mitochondria in the Balbiani body (Bb) form complexes with the perinuclear nuage on the opposite side of the nucleus, forming germline precursors (complexes of mitochondria and nuage-like material). In midprevitellogenic oocytes, the nucleus moves to a central position, continues to emit nuage, and the Bb forms a perinuclear ring. The mitochondria multiply and accumulate. Nuage, composed of threads appears and forms a spherical accumulation in close contact with the mitochondria. In late previtellogenic oocytes, the Bb enlarges and becomes fragmented. Fragments containing mitochondria, nuage, and complexes of mitochondria and nuage-like material, as well as Golgi complexes move to the ooplasm near the plasma membrane. The spherical accumulation of thread-like nuage is located at the vegetal pole. Various stages of autophagic degradation of mitochondria are present within autolysosomes (multilamellar bodies) in the Bb. These results support the hypothesis that the primary evolutionary role of the Bb is to select healthy mitochondria and transfer them to the next generation. The function of autolysosomes in the circulation and storage of membranes, and in the deposition of egg envelopes, is also discussed. Oocytes are covered by three primary egg envelopes, and their ultrastructure and deposition are described. Both the oocytes and the FCs are involved in this process.

Digital cameras1 and displays2 use picture elements (pixels3) that perform a single function: detecting or emitting light intensity. To exploit the full information content of electromagnetic waves, more advanced elements are required. This has driven the development of multifunctional components that, for example, simultaneously detect and emit intensity4,5 or extract intensity and spectral information6-8. However, no pixel exists that both senses and generates optical wavefronts with full control over amplitude, phase and polarization, limiting bidirectional control and feedback of sophisticated light fields. Here we present a route to such pixels by demonstrating a versatile platform of miniaturized diffractive elements based on Fourier optics9. We use plasmonic surface waves10, which propagate coherently11 and efficiently12-15 across metallic surfaces. When these plasmons are launched towards wavy microstructures16 designed with simple Fourier analysis, arbitrary and background-free optical wavefronts are generated. Conversely, incoming light can be sensed, and its amplitude, phase and polarization can be fully characterized. By combining or superposing several such components, we create multifunctional 'Fourier pixels' that provide compact and accurate control over the optical field. Our approach, which we extend to photonic waveguide modes, establishes a scalable, universal architecture for vectorially programmable pixels with applications in adaptive optics17,18, holographic displays19-21, optical communication22,23 and quantum information processing24.

Improvements in lithium-ion battery (LIB) safety rely on understanding the thermal runaway failure of the cells. Thermal abuse tests are done on LIBs to study their exothermic reaction kinetics and gaseous hazards. Typically, testing is conducted in either pressure vessels or accelerating rate calorimetry (ARC) systems. These experimental systems are often used with little cleaning between tests, raising questions about whether the accumulated or adhered vented products pose respiratory and other health concerns. Also, the guidelines on personal protective equipment (PPE) for researchers often do not specifically address hazards associated with LIB thermal abuse tests. There is a relative lack of data on what species might be re-emitted from these experimental systems and how standard PPE reduces exposure to any off-gassed species. To help answer some of these questions, this paper characterized gas emissions from a vessel containing LIB residue post-thermal runaway, detecting species including electrolyte solvents, dimethylcyclosiloxanes, and other low-volatility organic compounds. The most abundant species were ethylene carbonate (39 ppb) and propylene carbonate (34 ppb). None of the species concentrations from this well-ventilated vessel posed acute toxicity, but repeated exposure may result in chronic health impacts. Fabric samples from clothes exposed to the vessel headspace re-emit the adsorbed gases, which extends the duration of inhalation exposure for individuals. The low volatility of the species was further supported by partition coefficient values above one, indicating their persistence and dermal exposure risks. Respirator effectiveness against gases evolved from LIB residue was investigated. Suggestions on improving worker safety were given based on the results of this paper.

Quantum cascade lasers (QCLs) are semiconductor-heterostructure devices known for their emission in the mid-infrared and THz spectral regions. Due to their operating regime, their intrinsic linewidth is significantly narrower compared to bipolar semiconductor lasers. Here, we demonstrate that by implementing an external-cavity (EC) configuration based on a commercial diffraction grating, we have successfully induced a Fabry-Pérot QCL to emit on a single mode with a broadly-tunable wavelength in the range 4.29-4.44 μm. This very simple setup enhances the laser performance in terms of threshold current and emitted power. A detailed noise analysis has been carried out, which demonstrates that the EC configuration positively impacts the laser operation. In particular, the intrinsic linewidth is substantially reduced (by a factor of ~5), the full linewidth is also decreased (depending on the integration timescale), and the relative intensity noise is slightly reduced. These characteristics, which hold within the whole tuning range, make the EC-QCL a good candidate for spectroscopy applications where broad tunability and narrow linewidth are highly demanded.

Biomass-derived carbon quantum dots (BCDs) have attracted considerable research attention as a novel category of sustainable fluorescent nanomaterials, attributed to their adjustable photoluminescence, superior biocompatibility, and eco-friendly synthesis methods. BCDs are made from renewable biomass sources like plants, algae, animal byproducts, and microorganisms, following the principles of green chemistry. This makes them much better for the environment and cheaper to make than carbon dots made in the traditional way. The field still has three big problems, though: the luminescence mechanism is still not well understood, with different pathways like carbon-core and surface-state emissions not having a single theoretical framework; optical modulation strategies are still not well developed, with quantum yields often falling below 30% and poor batch-to-batch consistency making it hard to standardize applications; and not enough is known about in vivo metabolic pathways and long-term toxicity to allow for systematic toxicological evaluation and clinical translation. The complex luminescence mechanisms, including carbon-core-state, surface-state, molecular-state, and cross-linked enhanced emission (CEE), are thoroughly examined to clarify the structure-property relationships that dictate their optical behavior. By using controlled synthesis and surface modification techniques, BCDs can be made to emit light in the visible to near-infrared (NIR) range. This makes them perfect for use in different types of multimodal imaging, such as single-photon, multi-photon, and photoacoustic bioimaging. Their natural ability to emit light, along with their low toxicity to cells and high stability in light, makes it possible to see cells and tissues in high detail. We talk more about the problems we are having right now with standardizing synthesis and controlling optical properties with precision. Future research should concentrate on refining reaction conditions and clarifying luminescence mechanisms to promote the clinical application of BCDs as next-generation, sustainable imaging agents.

Atmospheric and vacuum distillation consume more than 1,100&#x2009;TWh&#x2009;year-1 and emit more than 160 million metric tonnes of CO2 equivalent annually1,2, making membrane-based pre-fractionation a compelling retrofit strategy for lowering the energy and carbon intensity of petroleum refining3-10. Here we demonstrate that porous polyacrylonitrile (PAN) membranes, typically used as support layers, achieve effective molecular refining of crude oil at steady state. Under tangential flow, PAN membranes exhibited high crude oil permeances of up to 0.591&#x2009;&#xb1;&#x2009;0.040&#x2009;l&#x2009;m-2&#x2009;h-1&#x2009;bar-1, a more than 23-fold increase over the previous benchmark (<0.1&#x2009;l&#x2009;m-2&#x2009;h-1&#x2009;bar-1)1,11, selectively yielding enriched lighter hydrocarbon fractions such as naphtha and kerosene. This unexpected selectivity arises from the dynamic deposition of heavy hydrocarbons within the initially approximately 15-nm surface mesopores, which narrows the pore diameter to sub-2-nm dimensions. Depth-resolved chemical identification reveals selective accumulation of n-alkanes, suggesting a self-limiting pore constriction mechanism that stabilizes selective transport pathways. Once the n-alkane deposition is stabilized, selective enrichment of raw crude oils occurs with sustained stability over 4&#x2009;weeks. Process simulations show that PAN-membrane-based pre-fractionation could reduce energy by 31.6%, cooling water by 20.7% and CO2 emissions by 37.6% compared with traditional atmospheric distillation.

TNF-&#x3b1; (Tumor Necrosis Factor) is a proinflammatory cytokine that amplifies inflammatory response and promotes leukocyte recruitment. TNF-&#x3b1; is primarily produced by activated macrophages, among others, in response to infection, inflammation, or tissue damage. Given its central role in normal and abnormal immune responses, it is the target of several therapeutics, such as adalimumab and etanercept. TNF-&#x3b1; is also a prognostic and diagnostic biomarker associated with rheumatoid arthritis, Alzheimer's disease, multiple sclerosis, several kidney diseases, cancers, type 2 diabetes, sepsis, and others. Because TNF-&#x3b1; levels change dynamically during inflammatory responses, tools capable of sensitive and spatially resolved detection could enable improved monitoring of immune activity and disease progression. Single-walled carbon nanotubes (SWCNT) are cylindrical carbon lattices that emit distinct near-infrared bandgap photoluminescence. In this work, we evaluated three aptamer-based sensor constructs, plus an additional two iterations of one aptamer sequence, and two antibody-based sensor constructs for TNF-&#x3b1; that use SWCNT near-infrared photoluminescence signal transduction. Several, but not all, of these aptamer and antibody-based sensors sensitively and selectively detected TNF-&#x3b1; in human and bovine serum in a physiologically relevant range, and we found that their sensing was impacted by both passivation and incorporating an exogenous quencher onto the aptamer sequence. This study highlights the importance and challenges of translating previously-validated molecular recognition elements to new detection conditions, in this case on the surface of SWCNT and in challenging serum conditions. It also validated a lead sensor, the VR11-SWCNT aptamer construct with or without quencher chemistry and with surface passivation, that builds upon constructs that failed in serum. These results demonstrate a strategy toward synthesis of nanoscale optical sensors capable of detecting TNF-&#x3b1;. We anticipate that the sensors evaluated here will have utility in both the diagnosis and study of inflammation-driven chronic disease, while the sensor assessment framework will help drive the broader field of molecularly specific diagnostics.

The rapid and sustainable construction of highly functionalized fluorophores remains a key challenge in organic synthesis. We detail a concise, metal-free synthetic platform for the preparation of unsymmetrical pyrrolyl-pyridine boron difluoride (BOPP) complexes from simple chalcone precursors. Central to this methodology is the optimization of a thiamine-mediated Stetter reaction under mild sonication, which efficiently generates key 1,4-diketone intermediates. Subsequent Paal-Knorr cyclization and BF3 complexation afford the desired BOPP dyes in good to excellent overall yields. This modular synthetic approach enabled facile expansion of the BOPP library, overcoming the inherent limitations of conventional cross-coupling methods. The synthesized BOPP fluorophores emit brightly in both solution and the solid state, featuring highly tunable emission profiles and large Stokes shifts of up to 88 nm. Supported by density functional theory (DFT) calculations, this study highlights the robustness of the synthetic protocol and establishes the unsymmetrical BOPP scaffold as a versatile platform for the development of next-generation fluorescent probes and functional optical materials.

Plants emit a wide range of volatile organic compounds, among which isoprene is the most abundant and atmospherically influential. Although oak species are major contributors to isoprene emission, there is considerable variation in isoprene emission capacity within the Fagaceae family. To unravel the evolutionary origins of isoprene emission, we investigated the molecular evolution of terpene synthase (TPS) genes across eight species within the Fagaceae. We identified a TPS-b subclade in which potential isoprene synthase (IspS) activity evolved independently in two gene lineages within subgenus Quercus. Ancestral sequence reconstruction revealed that the acquisition of a diagnostic amino acid residue for IspS function arose convergently in these lineages and was subject to positive selection, suggesting adaptive evolution. Ancestral-enzyme assays targeting the gene lineage with high gene expression revealed that the early protein primarily produced monoterpenes from geranyl diphosphate (GPP), whereas their descendants shifted substrate preference to dimethylallyl diphosphate (DMAPP), evolving into dedicated isoprene synthases. Our results indicate that IspS activity was not ancestral in Fagaceae, but evolved approximately 56 million years ago within the subgenus Quercus, and has been retained ever since. These findings emphasize the roles of enzyme structural innovation and regulatory shifts in the diversification of volatile terpenoid biosynthesis.

This article examines Thomas Morgan's medical ideas in the context of Newtonian iatromechanism in late seventeenth and early eighteenth-century Britain. In existing historiography, Morgan has been studied as a deist, but his medical writings have received little attention. In fact, Morgan has been classified as a Newtonian iatromechanist, but viewed as a minor figure in comparison with other Newtonians such as Archibald Pitcairne, George Cheyne, and James Keill. Such an assessment is partly due to the fact that Morgan did not have a social connection with Isaac Newton while others did, but also because Morgan's medical writing has been considered second-class and largely repeating earlier Newtonian works. However, close examination shows that though Morgan shared some common grounds with his predecessors, he developed original interpretations in many areas. Just like Pitcairne and his followers, Morgan looked upon an animal body as a complicated living machine whose life lay in the proper circulation of blood and other fluids through the small pipes distributed throughout the body. However, Morgan differed in that he, more than others, saw heat as an important factor in physiology. He thought that fire was condensed light and that the subtle substance of elementary fire was diffused through the universe. Heated air, or the air containing elementary fire breathed in acted as an expansive force to counterbalance the attractive forces between small particles in the animal body. According to Morgan, fever, which was considered a distinct disease at the time, was caused when the heated air in the blood was not properly evacuated or when the warmed body fluids were not cooled down. Morgan also argued that the main agent of digestion was the heat operating in the stomach. His heat-based interpretation was novel but fitted into the existing understanding of physical matters including the animal body, and it provided explanation about some physiological phenomena which were not fully explained before. The explanatory power of Morgan's medical writing earned him a good reputation as a physician among his contemporaries. In the context of the transition from iatromechanism to vitalism, part of Morgan's heat-based physiology may be considered as contributing to the shift, by proposing that the capacity to maintain body heat - that is, the ability to absorb, retain, and emit elementary fire and air - belonged solely to the living body.

Developmental plasticity allows organisms to adjust their phenotypes to match environmental conditions, but how sensory cues program specific physiological systems remains poorly understood. In Australian zebra finches, incubating parents emit heat calls during extreme temperatures, and embryos exposed to these acoustic signals develop enhanced thermal tolerance and altered growth trajectories as adults, a striking example of anticipatory programming. We hypothesized that heat call exposure alters embryonic hypothalamic gene expression, given this brain region's central role in integrating environmental signals and regulating metabolism, thermoregulation and growth. We exposed zebra finch embryos to playback of parental heat calls or control calls during late incubation and used RNA-sequencing of hypothalamic tissue to identify transcriptional responses. Contrary to predictions of widespread neuroendocrine reprogramming, heat call exposure produced targeted changes: robust downregulation of genes regulating vascular smooth muscle contraction and cytoskeletal dynamics, with coordinated isoform switching. Cell-type analyses revealed these molecular changes localized to vascular endothelial cells, smooth muscle cells and ependymal cells, the cellular components that control cerebral blood flow and regulate the brain's vascular barrier. Gene expression patterns suggest increased vascular plasticity that may protect against heat-induced cellular damage. Remarkably, these adaptive modifications occurred in response to an acoustic signal alone, without thermal exposure. Our results provide transcriptional evidence that prenatal acoustic cues may program cerebrovascular function through cell type-specific gene regulation, providing a novel mechanism for sensory-mediated developmental plasticity. This targeted vascular programming may represent a conserved strategy for anticipatory adaptation to predictable thermal challenges across endothermic vertebrates.

In semiconductors where three-phonon decay channels are suppressed, a mechanism termed "hot-phonon delocalization" induced by higher-order anharmonic decays emerges as the dominant process governing carrier thermalization. By combining ab initio solutions of the time-dependent coupled electron-phonon Boltzmann transport equations with femtosecond stimulated Raman spectroscopy, this study demonstrates that four-phonon couplings can substantially reshape the non-equilibrium carrier dynamics in semiconductors with significant phonon gaps, such as BAs and BSb. The results show that momentum-redistribution channels, specifically o+o&#x2192;o+o and o+a&#x2192;o+a, effectively delocalize hot phonons that initially accumulate in long-wavelength states by spreading them across the Brillouin zone. This behavior is fundamentally different from the conventional picture, where hot-phonon relaxation is assumed to be governed primarily by emission processes. This mechanism suppresses hot-phonon accumulation and enhances the efficiency of three-phonon Ridley- and Vall&#xe9;e-Bogani-type decays, mitigating the phonon bottleneck effect and ultimately improving Joule heating efficiency. In BAs, four-phonon coupling increases the energy dissipation rate of optical phonons nearly 70-fold, reducing phonon reabsorption and enabling high-energy electrons and holes to continuously emit optical phonons, as supported by our proposed phenomenological model. Consequently, the onset of phonon reabsorption heating is delayed from 6.0 to 12.9&#xa0;ps. These findings provide a comprehensive understanding of carrier thermalization, revealing that hot-phonon delocalization governs energy-exchange pathways in wide-phonon-gap semiconductors on the picosecond timescale.

The distribution coefficients (log Kd) of per- and polyfluoroalkyl substances (PFAS) were investigated in 84 soils from around Lyon, France. This area is located adjacent to an industrial facility that uses various PFAS in its production processes and that has been known to emit PFAS. A total of 77 target PFAS were analyzed in soil leachates using ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry (UHPLC-Orbitrap Q Exactive). While total PFAS concentrations in soil ranged from 3.8 to 175&#x202f;&#x3bc;g&#x202f;kg-1 dry weight, the corresponding concentrations transferred to the aqueous phase ranged from 3.0 to 1215&#x202f;ng&#x202f;L-1. A clear predominance of perfluoroalkyl carboxylic acids (PFCAs), including PFHxA, PFHpA, PFNA, PFPeA, and PFOA, was observed in the aqueous phase following soil-water equilibration across all soil types. The data were used to determine solid-liquid partitioning coefficients that can be used to model downward mobility of the PFAS. The resulting log Kd for the PFCAs (C3-C11) varied from 0.08 to 3.41&#x202f;mL&#x202f;g-1, while values for PFSAs (specifically PFBS (C4), PFHxS (C6), and PFOS (C8)) varied between 0.80 and 4.94&#x202f;mL&#x202f;g-1. Spearman's rank correlations between Kd values and soil properties (pH and SOC) for the 14 detected PFAS revealed that soil pH is a primary factor influencing PFAS partitioning, with statistically significant negative correlations for PFHxA and PFDA and highly significant negative correlations for PFBA, PFNA, PFUnDA, and PFHxS. In contrast, SOC (%) generally showed no significant influence on PFAS partitioning, except for PFBS and PFOA, which exhibited a strong, highly significant positive correlation.