The negatively charged nitrogen-vacancy center is a leading quantum platform due to its excellent spin coherence and stable interactions. Understanding its ultrafast dynamics is crucial for quantum applications but presents significant challenges for both experimental characterization and atomic-scale modeling. Here, we employ real-time time-dependent density functional theory to investigate the coupled electron-phonon-spin dynamics in negatively charged nitrogen-vacancy centers. Laser excitation promotes minority-spin electrons within 100 fs, establishing a C3v-symmetry breaking charge ordering. Subsequently, ionic motion on the potential energy surface of the excited electrons generates both symmetric oscillations of carbon-nitrogen bonds and dynamic Jahn-Teller distortions with a C3v-symmetry breaking. These distortions subsequently induce nonlocal coherent phonons in the diamond lattice, which propagate with the C3v-symmetry breaking at the sound velocity ( ~ 2 Å/fs). Our simulations provide direct time-resolved visualization of these processes, offering novel insights into the microscopic interplay of electrons, phonons, and spins in nitrogen-vacancy centers.
Many anti-cancer clastogens are known to induce DNA replication stress and ultimately DNA double-strand breaks (DSBs), one of the most deleterious forms of DNA damage and threat to genome integrity. However, the mechanism(s) by which these chemicals cause DSB is unclear. Our previous work suggested that they induce DSB at transcriptionally up-regulated genes, particularly those oriented in a head-on configuration with respect to incoming replication. Here, we rigorously test this model by simultaneously mapping the transcriptome and genome-wide DSBs induced by six replication stress induders with diverse mechanisms of action (hydroxyurea, methyl-methane sulfonate, camptothecin, actinomycin, doxorubicin and methotrexate). Our data show that replication stress-induced DSBs are enriched in genic regions and show a positive correlation with active transcription histone marks, particularly histone H3 lysine 36 tri-methylation. We further demonstrated that camptothecin-induced DSBs were significantly reduced by deletion of Set2, the known H3K36 methyltransferase, and to a lesser extent, by deletion of Rpd3, a histone deacetylase recognizing H3K36 trimethylation. Our data provide support for a model where DSBs are driven by replication inhibitor-induced replication-transcription conflict. More importantly, they reveal active transcription histone markers as the impediments for replication fork progression, therefore a direct culprit for DSBs.
Tailored ultrafast laser pulses provide a powerful means of selectively breaking bonds in polyatomic molecules. However, traditional laser control strategies often assume that reactions begin from pure eigenstates or thermal ensembles. Here, we present a theoretical framework that combines an ultrashort infrared (IR) pulse train with a time-delayed ultraviolet (UV) pulse to achieve selective photodissociation in HOD─a prototypical system for mode-selective chemistry. Our approach utilizes nonresonant infrared (NIR) pulse trains to drive impulsive stimulated Raman scattering (ISRS), thereby generating coherent superpositions of the O-H and O-D stretching vibrational modes in the ground electronic state. These vibrational coherences enable UV-induced quantum interference: a time-delayed UV pulse projects the prepared vibrational states onto a repulsive electronic state, resulting in bond-selective photodissociation. By tuning the pulse delay and adjusting molecular orientation, we can steer the reaction pathway and, under optimal conditions, reduce the H/D product ratio to 0.3. Our findings underscore the critical roles of vibrational coherence and pulse shaping in controlling chemical reactivity and offer an analytically transparent perspective that connects vibrational-state preparation to dissociation branching ratios.
Highly stabilized tris(dialkylamino)-triazatriangulenium (A-TATA+) and tris(methoxy)-triazatriangulenium (MeO-TATA+) carbenium ions have been synthesized and characterized as fluorescent dyes. As a result of the extensive delocalization of positive charge in the planar triangulenium system and the presence of six strongly electron-donating groups, these new carbenium ions display extreme cation stability. A linear correlation between cation stability (pK R+) and reduction potential (E red) has been established for the trianguleniums, leading to an estimated pK R+ value of 32 for A-TATA+, making A-TATA+ the most stable carbenium ion reported to date, surpassing the previous record by 7 pK R+ units. Furthermore A-TATA+ displays unique dye properties in the blue spectral region, with intense absorption at 447 nm (ε = 84 000 cm-1 M-1), and a high fluorescence quantum yield at 460 nm (ϕ f = 45%).
暂无摘要（点击查看详情）
According to previous studies, urogenital symptoms, including nocturia, worsen with the menopause and depression and quality of life decrease in women experiencing nocturia. This study aimed to determine the impact of nocturia on depressive symptoms and quality of life in menopausal women. This case-control study was conducted 110 premenopausal and 141 postmenopausal, who attended a Family Health Center in Ankara, Turkey, between July and September 2021. A total 251 menopausal women were included through convenience sampling. We utilized the World Health Organization Quality of Life Scale (WHOQOL-BREF), the Beck Depression Inventory (BDI), and the Sociodemographic Information Form. This study complies with the STROBE guideline. In this study, the incidence of nocturia was higher in postmenopausal women (%69, 5) compared to premenopausal women (%49, 1). Except for the general health and physical health sub-dimension mean scores of the WHOQOL-BREF scale, other sub-dimension scores were statistically significantly lower in women with nocturia than in women without (p < 0.05). The mean BDI scores were statistically significantly higher in women with nocturia (p < 0.05). It was determined that nocturia negatively affects the quality of life and increases the depressive symptoms in menopausal women. Healthcare professionals should assess urologic symptoms and psychological symptoms, including depressive symptoms.
暂无摘要（点击查看详情）
Chiral perovskites have emerged as a highly promising family of materials for circularly polarized light (CPL) detection, owing to their unique combination of structural chirality and remarkable optoelectronic performance. However, breaking the linear scaling law between chiroptical activity and intrinsic conductivity with dimensionality remains a substantial challenge toward high-performance CPL detection. Herein, through dimensional engineering involving the incorporation of a large cage cation and a chiral bifunctional bulky cation, a series of chiral layered hybrid perovskites (R/S-BrBA)2EA n-1Pb n Br3n+1 (n = 1 to 3; R/S-BrBA+: 3-amino-1-bromobutanium; EA+: ethylammonium) has been successfully constructed. By incorporating oversized EA+ within the layered perovskite lattices, two new pairs of multilayered hybrid perovskites (R/S-BrBA)2EAPb2Br7 (2R/S) and (R/S-BrBA)2EA2Pb3Br10 (3R/S) have been synthesized, which exhibit remarkable semiconducting properties, including small optical absorption edges (2.79 and 2.69 eV) and high photoconductive on/off ratio (>102 and 103). Strikingly, cooperatively driven by the large cation-induced lattice expansion and bifunctional cation-introduced halogen⋯halogen interaction, the chirality transfer from the organic to inorganic sublattices increases, and the chiroptical activity with an asymmetric factor was enhanced by 5.7 times as the n value increased, breaking the linear scaling law. Benefiting from the dimensional engineering, exceptional self-powered CPL detection with an anisotropy factor (g Iph) of up to 0.278 has been achieved in a photoelectric device fabricated with 3R single crystals. This study provides a pathway for the development of chiral perovskites that integrate high chiroptical activity and remarkable intrinsic conductivity, thereby enabling high-anisotropy self-powered CPL detection.
Sugars play a pivotal regulatory role in floral bud dormancy release in Prunus mume, a process that critically determines subsequent flowering time. However, the precise molecular mechanisms linking sugar metabolism to this developmental transition remain poorly understood. To address this gap, we integrated physiological profiling and transcriptomic sequencing using two cultivars with contrasting flowering phenologies: the early-flowering 'Chaotang Gongfen' (CTGF) and the late-flowering 'Shichu Jin' (SCJ). Exogenous sugar treatments were applied separately to floral buds of the cultivar 'Yilian' to evaluate the effect of sugars on dormancy release. During dormancy release, glucose and sucrose contents increased progressively and showed significant positive correlations with bud break rates in both CTGF and SCJ (r > 0.75). Consistently, exogenous application of glucose and sucrose significantly accelerated bud break in 'Yilian', whereas mannose exhibited an inhibitory effect. Transcriptome analysis of CTGF and SCJ revealed significant enrichment of starch and sucrose metabolism, hormone signal transduction, and stress-responsive pathways. Key metabolic genes, notably the α-amylase gene PmAMY1-2 and the cell wall invertase genes PmCWINV1/4, were upregulated during this transition. Weighted gene co-expression network analysis (WGCNA) further identified PmFRK4, PmSUS6, and the aforementioned invertases as candidate genes within a sugar-associated regulatory module. Collectively, these findings support a model in which glucose and sucrose accumulation promotes endodormancy release via the transcriptional activation of starch and sucrose catabolic pathways. This study provides a theoretical framework for deciphering dormancy regulation in woody perennials and offers potential targets for the precise manipulation of flowering time.
The American Board of Emergency Medicine (ABEM) has recently introduced a new Certifying Exam, which incorporates assessment of performance in a simulated clinical environment. Simulation-based assessments allow for reproducible, controlled evaluations. The residency program has a responsibility to prepare residents for the Certifying Exam and to verify resident competency. We sought to determine the feasibility of a simulation-based assessment program encompassing three domains (resuscitation, procedural skills, and communication) with assessments against pre-determined Minimum Competency Scores (MCS) to provide evidence for program director attestations of competence. Eight stations were chosen based on ABEM's Certifying Exam content, the Accreditation Council for Graduate Medical Education (ACGME) Milestones, and proposed Entrustable Professional Activities. Simulation-based case scenarios and assessment checklists were created with standard settings performed using the Mastery Angoff process. These stations were categorized into three different domains: resuscitation (Adult Medical, Pediatric Medical, Trauma, and Neonatal), procedural skills (Direct Laryngoscopy, Cricothyrotomy, and Central Venous Catheter Placement), and communication (Breaking Bad News). Results were summarized with descriptive statistics. Thirty emergency medicine residents at an academic Midwestern residency program underwent assessments over one year. None of the residents achieved the MCS on all eight assessments. Residents achieved the MCS on an average of 4.24 stations. There was large performance variability, particularly for the Pediatric Medical (27%-100% items correct), Neonatal Resuscitation (30%-100%), and Breaking Bad News (31%-100%) scenarios. A greater percentage of residents met the MCS for procedural assessments. This pilot study demonstrated the feasibility of a simulation-based assessment program designed to provide objective evidence of clinical competency. Assessment outcomes and associated feedback can be used by learners to guide the development of educational plans for performance improvement. Educators can use the resulting data to assess readiness for independent practice, prepare for the Certifying Exam, and identify content areas that may require additional program-wide education.
Constructing efficient conductive networks in flexible polymer matrices remains a central challenge in electromagnetic interference (EMI) shielding material design. In this work, a 'point-line' hybrid filler system combining conductive carbon black (CB) and multi-walled carbon nanotubes (MWCNTs) was incorporated into a silicone rubber matrix to systematically engineer the conductive network architecture. By optimising the CB/MWCNT blending ratio, a composite with a tensile strength of 8.5 MPa, elongation at break of 180%, and EMI shielding effectiveness of 50 dB was achieved at a 1:1 weight ratio. Further surface modification of the hybrid fillers using five surfactants, including sodium dodecylbenzene sulfonate (SDBS), cetyltrimethylammonium bromide (CTAB), polyvinylpyrrolidone (PVP), nonylphenol ethoxylate (NPEO), and octylphenol ethoxylate (OPEO), was systematically investigated. OPEO modification was proved the most effective, improving EMI shielding performance to 58 dB while enhancing tensile strength by 11.8% and elongation at break by 50%. These results demonstrate that rational filler hybridisation combined with targeted surfactant modification offers a practical and scalable route to high-performance flexible EMI shielding composites.
Russia's aggression against Ukraine has unfolded in two phases: the onset of the Donbas war and the annexation of Crimea in 2014, and the full-scale invasion in 2022. We examined the changes in Ukrainian scholarly publishing across these disruption periods. Using Web of Science Core Collection and InCites data (1991-2024), we analyzed publication trends in Ukraine and Croatia, disciplinary composition, leading universities, city-level output in occupied territories, and international collaboration. Interrupted time series (ITS) models were specified with breakpoints at 2014 and 2022. Ukraine's output increased from 331 articles in 1991 to 12,475 in 2021, then declined by 14.6% to 10,649 in 2024, whereas Croatia's output remained comparatively stable. The segmented ITS showed significant growth before 2014, a steeper upward trend after 2014, and a decline after 2022. Croatia showed continued growth with a smaller, non-significant post-2022 slowdown. In Ukraine, the largest post-2022 declines were observed in Physical Sciences and Social Sciences, while Engineering and Technology appeared more resilient. City-level analyses in occupied territories showed an early break in 2014 in Donetsk and Luhansk, while output linked to Simferopol and Sevastopol was rapidly reclassified after 2014, with records increasingly indexed under Russia. After 2022, collaboration with Russia collapsed, whereas partnerships with Poland, Germany, and the USA expanded. Ukrainian scholarly publishing showed phase-specific shifts in output and collaboration patterns that coincided with major geopolitical disruptions.
Tartrazine (E-102) and Sunset Yellow (E-110) are widely used synthetic azo food dyes, yet concerns remain regarding their hematological and genotoxic effects, particularly following repeated and combined exposure. This study evaluated the hematological toxicity and genotoxic potential of Tartrazine and Sunset Yellow, administered individually and in combination, using complementary in vitro and in vivo endpoints. In the in vitro design, lymphocytes from healthy donors were exposed to 250, 500, and 750 μg/mL of Tartrazine and Sunset Yellow, individually and in combination, for 3 h. In the in vivo study, Wistar rats were orally exposed to Tartrazine (3.75 and 15 mg/kg), Sunset Yellow (1.75 and 7 mg/kg), or their combinations for 7 and 21 days. Hematological parameters, including hemoglobin (Hb), RBCs count, hematocrit (Hct), and leukocyte profiles, were measured. Genotoxicity was assessed using the comet assay to detect DNA strand breaks and the micronucleus assay to assess fixed chromosomal damage. In vitro, both dyes induced significant DNA damage following individual and combined exposure. Similarly, in vivo, both dyes produced significant dose- and time-dependent hematological alterations, with Sunset Yellow producing more pronounced effects than Tartrazine. Combined exposure resulted in the greatest hematological disturbances. The comet assay revealed significant increases in DNA strand breaks, particularly following combined treatment, whereas micronucleus frequency was not significantly altered compared with controls. These findings indicate that short-term exposure to Tartrazine and Sunset Yellow disrupts hematological homeostasis and induces transient DNA damage, highlighting the need for further studies to evaluate the health implications of combined exposure to synthetic food dyes.
The Janus monolayers have recently attracted substantial interest due to their unique asymmetric structures and intriguing physical properties. In this work, we explore the thermoelectric properties of the Janus monolayer ZrBrI, using first-principles calculations and Boltzmann transport theory. We demonstrate that the system maintains good dynamic and thermal stability, as evidenced by the absence of imaginary phonon modes and small lattice fluctuation at a higher temperature of 600 K. The hybrid functional calculations reveal that the monolayer exhibits a relatively small indirect gap of 1.22 eV, and the energy bands near the conduction band minimum exhibit double degeneracy with weak dispersions, which is very beneficial for enhancing the n-type power factor. Meanwhile, a relatively lower lattice thermal conductivity is found due to strong lattice anharmonicity caused by the antibonding state and the symmetry breaking of the structure. Collectively, a larger ZT value of 3.9 at 600 K can be realized for the n-type Janus monolayer ZrBrI at an optimal concentration of 1.89×1013 cm-2, highlighting its promising thermoelectric application in the intermediate temperature region.
This study investigates a thermal management strategy for butyl/chloroprene rubber (IIR/CR) bladder compounds by incorporating hexagonal boron nitride (h-BN) as a thermally conductive filler to enhance heat transfer efficiency. Compounds containing 0, 10, 25, and 33 wt% h-BN were prepared via solution mixing to ensure uniform dispersion and subsequently vulcanized using a hot press. The materials were characterized in terms of morphology, cure behavior using a moving die rheometer (MDR), thermal conductivity, crosslink density, mechanical properties, and dynamic mechanical analysis (DMA). The incorporation of h-BN significantly enhanced thermal performance, nearly doubling the thermal conductivity at 33 wt%. MDR measurements demonstrated that this improved heat transfer capability accelerated the thermal onset of vulcanization, effectively reducing scorch time. Mechanical testing revealed a systematic increase in stiffness at application-relevant low strain levels (25-50%), attributed to hydrodynamic reinforcement, accompanied by a progressive increase in elongation at break. This enhanced extensibility is associated with the presence of lamellar h-BN platelets, which facilitate stress redistribution and promote dynamic chain mobility under deformation. DMA showed that h-BN incorporation increased the storage modulus and intensified the Payne effect, confirming the formation of a robust physical filler network. Overall, the incorporation of h-BN delivers a formulation pathway for energy-efficient tire curing bladders by significantly improving heat transfer efficiency and dimensional stability.
The taxane family of compounds, including paclitaxel, docetaxel (Taxotere), and cabazitaxel (Jevtana), are common drugs used in chemotherapy for the frontline treatment of most major types of cancer. Alopecia, the dramatic loss of hair, is a common side effect that became a symbol of the suffering of many cancer patients. Concerted efforts have been made to understand the mechanism of taxane toxicity to hair follicles and, thus, prevention methods. Taxanes act by stabilizing cellular microtubules, which consequently cause mitotic arrest and then failure, as microtubules play critical functions in chromosome segregation. Hair follicle matrix cells are highly proliferative and thus are exceedingly sensitive to taxanes. We review the cellular mechanism-based strategies under investigation to counter taxane-induced hair follicle damage. These include the application of cyclin kinase inhibitors to block mitotic entry, the practical method using scalp cooling to reduce exposure of scalp hair follicles to drugs during infusion, the requirement of p53 action for hair follicle damage, and the recently discovered method of using low-intensity ultrasound to break taxane-stabilized microtubules and thus reverse taxane toxicity in hair follicle matrix cells. The concept of low-intensity ultrasound as an antidote to taxanes may have the potential to provide a practical and compelling strategy to counter alopecia in cancer treatment using taxanes. Tweet: Taxanes (paclitaxel/docetaxel) are powerful microtubule-stabilizing cancer drugs, but they also cause adverse effects, including alopecia. New research discoveries of temporary microtubule disruption by low-intensity ultrasound may counteract taxane toxicity and prevent alopecia during cancer chemotherapy. "Mechanistic-based strategies for the prevention of taxane-induced hair follicle damage in cancer chemotherapy" OUTLINE: 1. Taxane/paclitaxel mechanism of action in cancer therapy. 2. Taxane side effects: Alopecia (hair loss). 3. p53 dependence of taxane-induced hair follicle damage. 4. Research efforts to counter taxane -induced alopecia by CDK4/6i. 5. Prevention of taxane chemotherapy side effects using scalp cooling. 6. Discovery of low-intensity ultrasound as an antidote for taxane cytotoxicity, and potential prevention of alopecia in chemotherapy using taxanes. 7. Summary and prospective.
Eucommia ulmoides gum (EUG), a sustainable plant-derived natural polymer, was functionalized via three distinct routes, including vulcanization, epoxidation, and hydroxylation to yield vulcanized (VEUG), epoxidized (EEUG), and hydroxylated EUG (HEUG), respectively. We systematically characterized the effects of modification route and degree on the chemical structure, crystallization behavior, thermal stability, hydrophilicity, and mechanical properties of functionalized EUG and further evaluated the high/low-temperature performance, microstructure, and mechanical properties of the corresponding modified asphalt binders (VEMA, EEMA, HEMA) as a function of modifier type and loading. For VEUG, C-S cross-linking networks formed during vulcanization suppress EUG crystallization, enabling a rigid-plastic to elastic transition, while high-temperature cleavage of C-S bonds reduces its initial thermal stability. For EEUG, epoxidation breaks C=C double bonds and introduces epoxy groups to strengthen intermolecular interactions; subsequent ring-opening grafting of hydroxyl groups onto EEUG yields HEUG, which forms additional cross-links via dynamic hydrogen bonds. Increasing modification degree for both EEUG and HEUG reduces their number- and weight-average molecular weights with narrower distribution, diminishes crystallinity, enhances thermal stability and hydrophilicity, and drives a rigid-plastic to elastic transition, characterized by decreased strength (0.65 MPa < σHEUG < σEEUG < 10.18 MPa) and markedly improved ductility (143.6% < εEEUG < 262.0%, 679.9% < εHEUG < 1360.3%). In asphalt binders, VEUG's cross-linked network endows VEMA with refined more abundant bee-like microstructures, drastically boosting high- and low-temperature performance: relative to pristine EUG-modified asphalt (EUGMA), VEMA's DMT modulus decreases by 94%, and adhesion increases by 87%. EEMA forms covalent bonds with polar asphalt components via epoxy groups, while HEMA constructs a hydrogen-bonded cross-linked network; both effectively inhibit asphaltene aggregation. With increasing modifier loading, EEMA and HEMA exhibit increased modulus, reduced adhesion, and gradually improved high- and low-temperature performance, except for the non-significant high-temperature enhancement of HEMA at higher loadings.
In this research, a novel polyarylene ether nitrile (PEN) coating material was fabricated through a facile stepwise polymerization method, which provides metallic substrates used in the oil industry with remarkable corrosion protection performance. A variety of characterization techniques were employed to evaluate the comprehensive properties of the PEN coating materials against a commercially established high-temperature-resistant epoxy coating. Based on the TGA curves, the PEN3 coating exhibited a T5% value of 521 °C, which was 44.72% higher than that of the epoxy coating. According to the tensile experiment, the PEN coatings demonstrated improved mechanical performance, achieving tensile strength and breaking elongation values of 89.37 MPa and 7.14% (PEN3), respectively, while the epoxy achieved values of 18.67 MPa and 0.32%, respectively. EIS tests revealed that all the PEN coatings exhibited superior corrosion resistance compared to the epoxy coating. Among them, the PEN3 coating remained intact without failure and showed the highest impedance value (5.665 × 107 Ω·cm2), which was two orders of magnitude higher than epoxy. Our research confirmed that the PEN coating material provided enhanced corrosion resistance, thermal stability and mechanical properties, positioning it as an alternative option to replace epoxy coating in prolonging the service life of steel piping in oil field applications.
Transistor-based computing faces a fundamental energy-resolution trade-off: lowering the conductance reduces the programming energy (Eprog) but simultaneously narrows the dynamic range (Gmax/Gmin) required for multilevel state discrimination. A memristor offers analog programmability, but it suffers from the same limitation because reducing the conductance decreases Gmax/Gmin, degrading the learning accuracy. Here, a path-decoupled III-V van der Waals (vdW) memtransistor overcomes this constraint via the spatial separation of the ionic and electronic transport pathways. Using HxK1-xGaSb2, K+ vacancies confined to the vdW gap serve as mobile ionic species, while holes conduct within the covalently bonded [GaSb2] layers. This decoupling yields a high K+ diffusivity and enables memristive switching at markedly reduced voltages. The memristive window Gmax/Gmin-which is set by ionic motion-remains invariant under gate modulation, whereas Eprog decreases via electrostatic control of the channel conductance. Consequently, the synaptic plasticity and neuromorphic inference maintain a high accuracy (>80%), while Eprog is reduced by more than an order of magnitude. The results establish ionic-electronic path decoupling as a general strategy for breaking the accuracy-energy trade-off in emerging neuromorphic hardware and position III-V vdW materials, which are promising candidates for application in low-energy, artificial intelligence accelerators.
In modern office environments, maintaining adequate air quality is essential for cognitive performance and overall well-being. However, the physiological effects of ventilation (CO2 control) during short daytime breaks, particularly midday naps, remain insufficiently explored. This study aimed to investigate the impact of ventilation on autonomic nervous system (ANS) activity using heart rate variability (HRV) metrics. A crossover experiment was conducted with six office workers (mean age: 28 ± 2 years). Two conditions were compared: Condition A (with ventilation/CO2 control) and Condition B (without ventilation). The experimental protocol consisted of three phases: Phase 1 (desk work, 11:00-12:00), Phase 2 (nap, 12:00-13:00, including a 20-25 min nap), and Phase 3 (post-nap desk work, 13:00-14:00). HRV indices (SDNN, RMSSD, CVRR, LF, HF, and LF/HF) were calculated from 5-min segments within each phase. A two-way mixed ANOVA revealed a significant main effect of ventilation on the LF/HF ratio during the post-nap phase (p = 0.0050, η2p = 0.9901), indicating improved autonomic stability upon awakening. Furthermore, a three-way mixed ANOVA (Sex × Order × Condition) showed that pNN50, an index of parasympathetic activity, exhibited significant interactions during the nap phase, including Condition × Sex (p = 0.0092) and the three-way interaction (p = 0.0333). Significant Order effects were also observed for heart rate (HR) across all phases (p < 0.05), suggesting habituation to the experimental environment. These findings indicate that ventilation is a critical environmental factor influencing physiological recovery during midday naps. Optimizing air quality may enhance autonomic regulation and improve the restorative effects of short daytime sleep in office settings. These findings should be interpreted as exploratory due to the small sample size (n = 6). While LF/HF was used as an index of autonomic balance, its physiological interpretation remains debated and should be considered with caution.