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The paddlewheel-type dimetal core ([M 2 ]) is a ubiquitous motif in the nodes in coordination polymers (CPs) and metal-organic frameworks (MOFs). However, their preparation has relied on ligand-substitution-labile metal ions owing to challenges associated with crystallization. Consequently, examples featuring ligand-substitution-inert metal ions, such as Ru or Rh, are scarce. This study presents the synthesis of novel reticular imine-linked CPs incorporating the paddlewheel-type diruthenium(II, II) ([Ru 2 II,II ]; 1-Ru) or dirhodium(II, II) ([Rh 2 II,II ]; 1-Rh) subunits. The synthetic approach involved a Schiff base dehydration condensation reaction between p-formylbenzoate-bridged [Ru 2 II,II ] or [Rh 2 of CO after 24 h of irradiation, whereas the 1-Rh system generated a lower amount of CO (3.2×10 II,II ] precursors (i. e., CHO-Ru and CHO-Rh, respectively) and 2,5-dimethyl-1,4-phenylenediamine in a 1 : 2 ratio. The catalytic activities of 1-Ru and 1-Rh for the photochemical reduction of CO 2 in a heterogeneous system depended on the metal site. The 1-Ru system exhibited exceptional selectivity, generating 3.0×10 4  μmol g -1 of CO after 24 h of irradiation, whereas the 1-Rh system generated a lower amount of CO (3.2×10 3  μmol g -1 ). The catalytic activity of 1-Ru ranked with that of all relevant catalytic systems. This study paves the way for the exploration of [Ru 2 II,II ]- or [Rh 2 II,II ]-based polymers with open metal site-dependent functional properties., (© 2024 The Authors. ChemSusChem published by Wiley-VCH GmbH.)

Aim: The study aimed to quantitatively clarify the effects of several weeks of static stretching on the flexibility of the rectus femoris muscle using shear wave elastography., Material and Methods: Fifteen healthy men (age: 26.4 ± 2.2 years) were instructed to perform 5 min of voluntary static stretching of their right rectus femoris muscles five times a week for four weeks. The participants adjusted their stretching inrectus femoris muscle tensity to a point immediately before experiencing discomfort or pain. The Young's modulus of the rectus femoris muscle and the knee-flexion range of motion were measured as indicators of flexibility. The Young's modulus was measured using shear wave elastography. Measurements were performed at baseline, as well as at two and four weeks after the stretching program started. A generalized linear mixed model was used to assess the change in the Young's modulus after the stretching program and the effects of the Young's modulus on the knee-flexion range of motion., Results: The Young's modulus of the rectus femoris muscle decreased after two and four weeks of stretching compared with the baseline ( p = 0.0004 and p <0.0001, respectively). The Young's modulus of the rectus femoris muscle and the four-week duration of stretching affected the knee-flexion range of motion ( p = 0.0242 and 0.0016, respectively)., Conclusions: Shear wave elastography quantitatively revealed that several weeks of static stretching increased the flexibility of the rectus femoris muscle in healthy men. A four-week static stretching regimen reduced the Young's modulus of the rectus femoris muscle and increased the knee-flexion range of motion., Competing Interests: Conflict of interest The authors do not report any financial or personal connections with other persons or organizations that might negatively affect the contents of this publication and/or claim authorship rights to this publication., (© 2024 Bungo Ebihara et al., published by Sciendo.)

Organic molecules with an aggregation-induced emission (AIE) property have been attracting much attention from the viewpoint of application to solid state emissive materials. For the AIE mechanism, quantum mechanical studies proposed the restriction of the intramolecular motion (RIM) model with the contribution of the conical intersection (CI) and deduced the importance of the restricted access to a conical intersection (RACI) in the potential energy surface (PES). Although these theoretical studies have contributed to the elucidation of AIE phenomena, direct detection of the reaction dynamics is indispensable to clarify the actual PES and the deactivation mechanism. Along this line, we investigated excited state dynamics of the AIE molecule with dibenzoylmethanatoboron difluoride complexes using time-resolved absorption spectroscopies in both visible and infrared (IR) regions. While the reference system of 1,3-bis(4-methoxyphenyl)methanatoboron difluoride (2aBF 2 ) showed strong emission in solution, the methyl-substituted derivative at the α-position of the dioxaborine ring (2amBF 2 ) led to the very weak fluorescence in solution but strong emission in the solid state. Time-resolved visible absorption measurements revealed a peak shift and broadening of the stimulated emission in the solution of 2amBF 2 , owing to the rapid change of the molecular geometry. With the temporal evolution of time-resolved IR absorption signals and density functional theory (DFT) calculation of these systems, it was deduced that 2amBF 2 has two stable geometries, namely, planar and bending, in the S 1 state and the bending geometry in the S 1 state led to rapid conversion to the S 0 state. These results support the RACI model in the aggregated states, leading to the AIE properties.

Although a widely used and important industrial chemical, carbon disulfide (CS2) also poses a number of hazards due to its volatility and toxicity. As such, the development of multifunctional materials for the selective capture and easy recognition of CS2 is one of the crucial issues. Herein, we demonstrate completely selective CS2 adsorption among trials involving H2O, alcohols, volatile organic compounds (including thiol derivatives), N2, H2, O2, CH4, CO, NO, and CO2. We also showcase its fine detection using remarkable luminescent response in an Au(I)-based metal-organic framework (MOF) of {ZnII(pz)[AuI(CN)2]2} (pz = pyrazine; 1) with a two-fold interpenetration network. Ex situ single crystal X-ray diffraction for 1 and CS2 accommodated 1 suggested that the Au···Au atoms are not only luminescent centers but also act as interaction sites for CS2 modulating the Au···Au contacts. These experiments revealed the specificity of CS2 and how changes in the CS2-induced structure. Based on the obtained structural formation, 1 exhibited a sensitive detecting ability for CS2 with an ultrafast response time of less than 10 s. Ex situ time-resolved photoluminescence analyses developed in this work implied that CS2 varied the energetic relaxation at the excited states related to the luminescent efficiency of the resultant MOF system., (© 2024 Wiley‐VCH GmbH.)

Herein, we report the synthesis and properties of triptycene-based C 3v - and C s -symmetric stable triradicals. SQUID magnetometry showed the propeller-shaped triradicals were both an antiferromagnetic equilateral triangle spin system with small spin-spin interactions J/k B ~-120 K and -106 K, leading to ca. 4/6 coexistence of the doublet/quartet states in thermal equilibrium at room temperature. The triradicals exhibited characteristic NIR absorption bands reaching 1000 nm, which was solely ascribed to the triradical in the doublet state by variable-temperature spectroscopic studies and quantum chemical calculations. Taking advantage of the spin-specific absorption feature, we found that the triradicals in the low-spin state undergo symmetry-breaking charge transfer, while those in the high-spin state fall into a monoradical-like excited state., (© 2024 Wiley-VCH GmbH.)

Soft materials that respond to external stimuli are promising candidates for next-generation actuators with human-friendly nature 1,2 . Among various stimuli to induce strain, light offers spatial selectivity, which allows versatile motion of a continuous body. However, spatial selectivity of photoactuation has been limited in two dimension due to the predominant absorption of photons by chromophores near a light source in accordance with Beer-Lambert law. Here, we report the deformation of crosslinked liquid-crystalline polymer films triggered by two-photon absorption. The films containing azotolane moieties show photoinduced deformation upon irradiation with fs laser pulses through two-photon absorption. The direction of photoinduced bending is controlled by depth-selective excitation with a focused laser beam. Furthermore, the mode of deformation is transformed from bending to twisting by irradiating spots near an edge of the film. Inhomogeneous photoirradiation with high spatial selectivity allows an infinite variation of three-dimensional motions even apart from preprogrammed behavior, which would be advantageous especially in application to microactuators., (© 2024. The Author(s).)

Molecule-based hybrid layered magnets provide an ideal platform for investigating the long-range spin-ordering process in low-dimensional magnetic systems. Within this context, a promising area of research is spin-sandwiched hybrid layered magnets. These materials offer the potential to explore how the spin, which is sandwiched between magnetic layers, is influenced by the internal magnetic fields generated by the magnetic layers. Herein, we report a layered ferrimagnet with intercalated biferrocenium ([bifc] + ) radicals, [bifc][{Ru 2 (2,3,5,6-F 4 ArCO 2 ) 4 } 2 (TCNQF 2 )] (1, TCNQF 2 = 2,5-difluorotetracyano- p -quinodimethane). The [{Ru 2 (2,3,5,6-F 4 ArCO 2 ) 4 } 2 (TCNQF 2 )] - moiety acts as a ferrimagnetic layer with S T = 3/2, composed of a paddlewheel [Ru 2 II,II (2,3,5,6-F 4 ArCO 2 ) 4 ] (2,3,5,6-F 4 ArCO 2 - = 2,3,5,6-tetrafluorobenzoate) with S = 1 and 2,5-difluoro-7,7,8,8-tetracyanoquinodimethanate (TCNQF 2 ˙ - ) units with S = 1/2 in a 2 : 1 ratio. The isostructural paramagnetic compound [bifc][{Rh 2 (2,3,5,6-F 4 ArCO 2 ) 4 } 2 (TCNQF 2 )] (2) consisting of diamagnetic [Rh 2 II,II (2,3,5,6-F 4 ArCO 2 ) 4 ] components was also synthesized. An investigation of the properties of 2 revealed minimal magnetic interaction between the [bifc] + and TCNQF 2 ˙ - components. Compound 1 displayed long-range ferrimagnetic ordering at the Curie temperature of 105 K without any frequency dependence on alternating current (AC) susceptibility, due to the combination of predominant ferrimagnetic ordering within the layer and interlayer ferromagnetic dipole interactions. However, subsequent stepwise magnetic ordering involving a strong AC frequency dependence was observed upon further cooling. These dynamic behaviors are associated with the ordering of two types of anisotropic [bifc] + spins between the ferrimagnetic layers, indicating that [bifc] + spin ordering is sensitive to anisotropic internal magnetic fields generated by the ferrimagnetic layers., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Objective: We aimed to clarify the relationship between the changes in echo intensity (EI) and Young's modulus of the soleus (SOL) muscle after ankle fracture surgery., Methods: Sixteen participants after ankle fracture surgery participated in this study (mean age: 46.8 ± 21.4 years). At three and five months after surgery, ankle range of motion (ROM), ankle strength, SOL muscle EI, and Young's modulus were measured, and changes in values were calculated. The EI was measured using the B-mode and ImageJ software (National Institutes of Health, Bethesda, MD), and Young's modulus was measured using shear wave elastography (SWE). The EI values corrected for subcutaneous fat thickness were calculated. Correlation and simple regression analysis were used to clarify the relationship between the amount of change in EI, the amount of change in Young's modulus, and the amount of change in ankle ROM., Results: Simple regression analysis showed that the amount of change in EI influenced the amount of change in Young's modulus of the SOL muscle (r = 0.623; p = 0.010) and the amount of change in ankle dorsiflexion ROM with the knee flexed (r = -0.702; p = 0.002)., Conclusion: The change in EI of the SOL muscle affected the change in Young's modulus after ankle fracture surgery. Clinically, changes in the EI may reflect changes in muscle stiffness., Competing Interests: Human subjects: Consent for treatment and open access publication was obtained or waived by all participants in this study. The Ethics Committee of Tsuchiura Kyodo General Hospital issued approval (2024FY32). The study was conducted in accordance with the Declaration of Helsinki. Animal subjects: All authors have confirmed that this study did not involve animal subjects or tissue. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Miyasaka et al.)

Yokoi A, Miyasaka H, Ogawa H, Itoh S, Okazaki H, Sonoda S. Effect of combining an upper limb rehabilitation support robot with task-oriented training on severe upper limb paralysis after spinal cord infarction: A case report. Jpn J Compr Rehabil Sci 2024; 15: 42-48., Objective: This study examined the effect of an upper limb rehabilitation support robot and task-oriented training on treating a patient with severe upper limb paralysis after spinal cord infarction who required total assistance with self-care., Case: A 60-year-old man was diagnosed with watershed infarction in the C5-7 spinal cord region. He was admitted to our hospital 18 days after onset of the disease. The patient had severe paralysis of both upper limbs, and the total score for the Functional Independence Measure (FIM) motor items was 25 points. Regarding the Canadian Occupational Performance Measure (COPM), three goals were listed: "eating," "going to the toilet," and "raising one's hand in a meeting." The performance of "going to the toilet" was rated three points, and the performance and satisfaction of other items were one point. The intervention was practiced for 1 h/day, mainly items selected from COPM. The training using an upper limb rehabilitation support robot was added for 1 h/day. The upper limb rehabilitation support robot adjusted the range of motion and dosage according to the patient's motor function level and recovery status. About three months after admission, he improved until his upper limbs could be held in space on activities of daily living (ADL), and the total score for the FIM motor items improved to 81 points. The satisfaction and performance of all items listed as goals in COPM at the time of admission improved to ten points, and the patient was discharged 108 days after admission., Conclusions: The upper limb rehabilitation support robot training that matched the level of motor function improved the motor function and active range of motion (ROM). ADL generalization through task-oriented training helped improve self-care. The use of COPM for the training to enable the patient to acquire the ability to perform meaningful activities led to improved COPM performance and satisfaction., Competing Interests: Conflict of Interests: The authors have no conflict of interest directly relevant to the content of this article., (©2024 Kaifukuki Rehabilitation Ward Association.)

Background: Diabetic macular edema (DME) causes vision impairment and significant vision loss. Portable optical coherence tomography (OCT) has the potential to enhance the accessibility and frequency of DME screening, facilitating early diagnosis and continuous monitoring. This study aimed to evaluate the reliability of a portable OCT device (ACT100) in assessing DME compared with a traditional stationary OCT device (Cirrus 5000 HD-OCT plus). Methods: This prospective clinical investigation included 40 eyes of 33 patients with DME. Participants with significant refractive errors (myopia > -6.0 diopters or hyperopia > +3.0 diopters), vitreous hemorrhage, tractional retinal detachment, or other ocular diseases affecting imaging were excluded. Spectral-domain OCT was performed by a single examiner using both devices to capture macular volume scans under mydriasis. Central macular thickness (CMT) was evaluated using the analysis software for each device: Cirrus used version 6.0.4, and ACT100 used version V20. We analyzed inter-evaluator and inter-instrument agreements for qualitative assessments of the intraretinal fluid (IRF), subretinal fluid (SRF), and epiretinal membrane (ERM) using Cohen's kappa coefficient, whereas quantitative CMT assessments were correlated using Spearman's correlation coefficient. Results: Substantial inter-evaluator agreement for IRF/SRF (κ = 0.801) and ERM (κ = 0.688) with ACT100 and inter-instrument agreement (κ = 0.756 for IRF/SRF, κ = 0.684 for ERM) were observed. CMT values measured using ACT100 were on average 29.6 μm lower than that of Cirrus (285.8 ± 56.6 vs. 315.4 ± 84.7 μm, p < 0.0001) but showed a strong correlation (R = 0.76, p < 0.0001). Conclusions: ACT100 portable OCT demonstrated high reliability for DME evaluations, comparable to that of stationary systems.

Objective: Although shear-wave elastography (SWE) can be used to assess muscle stiffness, SWE assessments are expensive. Echo intensity (EI) is an indicator of muscle quality and can potentially be used to assess muscle stiffness. This study aimed to determine the relationship between the EI and Young's modulus of the soleus (SOL) muscle after ankle fracture surgery., Methods: Eighteen participants who had undergone ankle fracture surgery were evaluated (mean age: 48.8 ± 20.6 years). Three months post-surgery, Young's modulus and EI of the SOL muscle were measured using SWE and the combination of B-mode ultrasound and ImageJ software, respectively. EI and Young's modulus measurements were obtained with the participant kneeling with knees bent 90°, upper body supported on a table, and ankles dorsiflexed 10°. The regions of interest used to measure EI and Young's modulus were identical. The EI value corrected for the subcutaneous fat thickness was also calculated. Pearson's correlation coefficients were calculated to examine the relationship of Young's modulus with the uncorrected and corrected EI., Results: Although the uncorrected EI was correlated with Young's modulus of the SOL muscle (r = 0.567; p = 0.014), the corrected EI showed a stronger correlation (r = 0.637; p = 0.005). High intra-rater was also found reliability for the EI and Young's modulus measurements of the SOL muscle in participants after ankle fracture surgery., Conclusions: The EI and Young's modulus of the SOL muscle were positively correlated. In particular, the corrected EI showed a stronger correlation with Young's modulus than the uncorrected EI. Clinically, EI measurements may facilitate objective evaluation of muscle stiffness., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. The Ethics Committee of Tsuchiura Kyodo General Hospital issued approval with reference number 2024FY32. Animal subjects: All authors have confirmed that this study did not involve animal subjects or tissue. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Miyasaka et al.)

The high surface area, open pore-structure and atomic-level organization inherent in many covalent organic frameworks (COFs) make them an attractive polymer platform for developing functional materials. Herein, a chemically robust 2D COF (TpOMe-DAPQ COF) containing phenanthraquinone moieties was prepared by condensing 2,4,6-trimethoxy-1,3,5-benzenetricarbaldehyde (TpOMe) and 2,7-diamino-9,10-phenanthraquinone (DAPQ) using the convenient mechanochemical method. The poor charge-storage capacity of the pristine TpOMe-DAPQ COF was substantially improved by first investigating its redox-site accessibility (RSA) using different conductivity-enhancement methods, and then optimizing the amount of EDOT needed to perform an in-situ polymerization. The resulting composite (0.4EDOT@TpOMe-DAPQ) was characterized and its enhanced charge-storage capabilities enabled it to be used as an anode material in an aqueous Mn beaker-cell battery capable of delivering 0.76 V. This work outlines the rational design approach used to develop a functional charge-storage material utilizing a COF-based polymerization platform., (© 2024 The Authors. ChemPlusChem published by Wiley-VCH GmbH.)

The increased anthropogenic emission level of CO 2 urges the development of CO 2 -responsive materials, but is it possible to regulate the inherent electronic properties through weak physisorption of a ubiquitous gas such as CO 2 ? Herein, we intended to answer this imperative question by the first case of CO 2 -actuated variable spin-state stabilisation in an interdigitated Hofmann-type coordination polymer [Fe II Pd(CN) 4 L 2 ] (1, L = methyl isonicotinate), showing a wide shift in transition temperature ( T eq ) from 178 K at P CO 2 = 0 kPa to 229 K at P CO 2 = 100 kPa. Interestingly, the emergence of a stepped behaviour in the heating process below P CO 2 = 10 kPa and overlapping magnetic susceptibility values above P CO 2 = 10 kPa elucidate the selective LS state stabilisation solely correlated with the extent of CO 2 accommodation. Based on the magnetic response and phase transition diagrams obtained under respective P CO 2 , a plausible scenario of the spin-state switching can be interpreted as (1 ls + ) → (1 hs + ) → 1 hs at P CO 2 ≤ 10 kPa, → 1 hs at 100 kPa < P CO 2 ≥ 32 kPa and → → 1 hs at 100 kPa, where 1 and 1' represent CO 2 -free and CO 2 -encapsulated states, respectively. The cooperative CO 2 sorption with SCO based on the varied CO 2 pressure corroborates a novel case for developing CO 2 -responsive magnetic materials henceforth., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Understanding physicochemical property changes based on reaction kinetics is required to design materials exhibiting desired functions at arbitrary timings. In this work, we investigated the photodimerization of anthracene derivatives in single crystals. Single crystals of 9-cyanoanthracene (9CA) and 9-anthraldehyde (9AA) exhibited reaction front propagation on the optical length scale, while 9-methylanthracene and 9-acetylanthracene crystals underwent spatially homogeneous conversion. Moreover, the sigmoidal behavior in the absorbance change associated with the reaction was much pronounced in the case of 9CA and 9AA and correlated with the observation of heterogeneous reaction progress. A kinetic analysis based on the Finke-Watzky model showed that the effective quantum yield of the photochemical reaction changes by more than an order of magnitude during the course of the reaction in 9CA and 9AA. Both the reaction front propagation and nonlinear kinetic behavior could be rationalized in terms of the difference in the cooperativity of the reactions. We propose a plausible mechanism for the heterogeneous reaction progress in single crystals that depends on the magnitude of the conformational change required for reaction. Our results provide useful information to understand the connection between photochemical reaction progress in the crystalline phase and the dynamic changes in the physicochemical properties., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Background: Recent studies have suggested that N-methyl-D-aspartate (NMDA) receptors are involved in the cell proliferation in several tumors. However, there have been no reports demonstrating the expression of NR1 subunit of the NMDA receptor in large cell neuroendocrine carcinoma (LCNEC)., Case Presentation: Here, we report the first elderly case of paraneoplastic anti-NMDA receptor encephalitis associated with LCNEC of the lung with NR1 expression. Of note, NR1 subunit expression in the tumor cells of the present case was confirmed by immunohistochemistry (IHC). Radiation therapy and immunotherapies, such as corticosteroids and intravenous immunoglobulin (IVIG), shrank the tumors and improved neurological symptoms in the present case. Additionally, we also confirmed the expression of NR1 in the tumor cells obtained from three other cases with LCNEC of the lung at our hospital by IHC., Conclusion: Our IHC results indicate that LCNEC generally expresses NR1 subunit and NMDA receptor may be involved in the tumor development and growth., (© 2024. The Author(s).)

Background: Drivers with dementia are at a higher risk of motor vehicle accidents. The characteristics of driving behaviour of patients with mild cognitive impairment (MCI) and Alzheimer's disease (AD) have not been fully elucidated. We investigated driving ability and its relationship with cognitive function and magnetic resonance imaging (MRI) morphometry indicators., Methods: The driving abilities of 19 patients with AD and 11 with amnestic MCI (aMCI) were evaluated using a driving simulator. The association between each driving ability parameter and the Mini-Mental State Examination (MMSE) score or voxel-based specific regional analysis system for AD (VSRAD) was assessed., Results: Patients with AD made a significantly higher number of operational errors than those with aMCI in attention allocation in the complex task test (P = 0.0008). The number of operational errors in attention allocation in the complex task test significantly and negatively correlated with MMSE scores in all participants (r = -0.4354, P = 0.0162). The decision time in the selective reaction test significantly and positively correlated with the severity and extent of medial temporal structural atrophy (r = 0.4807, P = 0.0372; r = 0.4862, P = 0.0348; respectively)., Conclusion: An increase in the operational errors for attention allocation in the complex task test could be a potential indicator of progression from aMCI to AD. Atrophy of the medial temporal structures could be a potential predictor of impaired judgement in driving performance in aMCI and AD. A driving simulator could be useful for evaluating the driving abilities of individuals with aMCI and AD., (© 2024 Japanese Psychogeriatric Society.)

Optical coherence tomography (OCT) is an indispensable instrument in ophthalmology; however, some facilities lack permanent OCT devices. ACT100, a portable SD-OCT system, allows for medical examinations at hospitals that do not have OCT and house calls. We investigated the usefulness of ACT100 by examining the reproducibility of retinal thickness measurements in 35 healthy participants with normal eyes using ACT100 and Cirrus. Using two OCTs, the OCT imaging of both eyes of each subject was performed. Macular retinal thickness was evaluated using the average value in nine lesions of the Early Treatment Diabetic Retinopathy Study (ETDRS) circle. Both models captured images in all cases. In the right eye, mean retinal thickness was significantly lower than in the ACT100 group in all regions; however, the measured values correlated well. The intraclass correlation coefficients showed the same high reliability as the Cirrus. The coefficients of variation (CVs) of both models showed little variation and high stability; however, the CV of ACT100 was significantly higher. The left eye was almost identical. Macular retinal thickness measured using ACT100 showed slightly greater variability than that by Cirrus; the reproducibility was good and correlated well with that of Cirrus. This technique is a suitable alternative to conventional OCT.

The effect of whole-body vibration (WBV) stretching on soleus (SOL) muscle stiffness remains unclear. Therefore, we aimed to investigate the acute and long-term effects of stretching with WBV on SOL muscle stiffness. This study employed a repeated-measures experimental design evaluating 20 healthy young males. SOL muscle stretching with WBV was performed for 5 min per day (1 min per set, five sets) over 4 weeks, for 4 days a week. Participants stretched the SOL muscle with ankle dorsiflexion in a loaded flexed knee position on a WBV device. Data were obtained to examine acute effects before stretching, immediately after stretching, and at 5, 10, 15, and 20 min. Moreover, data were obtained to examine the long-term effects before stretching, immediately after the completion of the 4-week stretching program, and at 2 and 4 weeks later. SOL muscle stiffness was measured using Young's modulus with shear wave elastography. The acute effect of SOL muscle stretching with WBV persisted for up to 20 min. Additionally, the long-term effect of stretching was better maintained than the acute effect, which was effective for up to 4 weeks ( p < 0.001). Clinically, continuous stretching with WBV may be used to improve SOL muscle stiffness in rehabilitation programs.

Polycyclic aromatic hydrocarbons (PAHs) are fragments of graphene that have attracted considerable attention as a new class of carbon-based materials. The functionalization of edge positions in PAHs is important to enable the modulation of physical and chemical properties essential for various applications. However, straightforward methods that combine functional group tolerance and regioselectivity remain sought after. Here we report a photochemical approach for the direct alkylation of carbon-hydrogen bonds in PAHs that takes place in a regiospecific manner, an outcome that has never been achieved in related thermal reactions. A reaction mechanism involving a single electron transfer process from photo-excited PAHs to sulfones, and a rationale for the origin of regioselectivity are proposed on the basis of spectroscopic analyses and theoretical calculations., Competing Interests: The authors declare no conflicts of interest., (This journal is © The Royal Society of Chemistry.)

Near-infrared two-photon absorption and excited state dynamics of a fluorescent diarylethene (fDAE) derivative were investigated by time-resolved absorption and fluorescence spectroscopies. Prescreening with quantum chemical calculation predicted that a derivative with methylthienyl groups (mt-fDAE) in the closed-ring isomer has a two-photon absorption cross-section larger than 1000 GM, which was experimentally verified by Z-scan measurements and excitation power dependence in transient absorption. Comparison of transient absorption spectra under one-photon and simultaneous two-photon excitation conditions revealed that the closed-ring isomer of mt-fDAE populated into higher excited states deactivates following three pathways on a timescale of ca. 200 fs: (i) the cycloreversion reaction more efficient than that by the one-photon process, (ii) internal conversion into the S 1 state, and (iii) relaxation into a lower state (S 1 ' state) different from the S 1 state. Time-resolved fluorescence measurements demonstrated that this S 1 ' state is relaxed to the S 1 state with the large emission probability. These findings obtained in the present work contribute to extension of the ON-OFF switching capability of fDAE to the biological window and application to super-resolution fluorescence imaging in a two-photon manner., (© 2024. The Author(s).)

Practicing walking in a safety suspension device allows patients to move freely and without excessive reliance on a therapist, which requires correcting errors and may facilitate motor learning. This opens the possibility that patients with subacute stroke may improve their walking ability more rapidly. Therefore, we tested the hypothesis that overground gait training in a safety suspension device will result in achieving faster supervision-level walking than gait training without the suspension device. Twenty-seven patients with stroke admitted to the rehabilitation ward with functional ambulation categories (FAC) score of 2 at admission were randomly allocated to safety suspension-device group (SS group) or conventional assisted-gait training group (control group). In addition to regular physical therapy, each group underwent additional gait training for 60 min a day, 5 days a week for 4 weeks. We counted the days until reaching a FAC score of 3 and assessed the probability using Cox regression models. The median days required to reach a FAC score of 3 were 7 days for the SS group and 17.5 days for the control group, which was significantly different between the groups ( P  < 0.05). The SS group had a higher probability of reaching a FAC score of 3 after adjusting for age and admission motor impairment (hazard ratio = 3.61, 95% confidence interval = 1.40-9.33, P  < 0.01). The gait training with a safety suspension device accelerates reaching the supervision-level walking during inpatient rehabilitation. We speculate that a safety suspension device facilitated learning by allowing errors to be experienced and correct in a safe environment., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

In [Mn(5-MeOsalen)(Cl)] 2 (dibenzo[24]crown-8), dibenzo[24]crown-8 formed a supramolecule via multi-point interactions with the [Mn(5-MeOsalen)(Cl)] dimer. The dimer was magnetically isolated with S T = 4 and weak interdimer magnetic interactions. The crystal exhibited single-molecule magnet behaviour with an anisotropic barrier of 26(1) K, which is the highest among the Mn-salen series reported to date.

Background: Stiffness of the soleus muscle (SOL) and Achilles tendon (AT) are associated with Achilles tendinitis and medial tibial stress syndrome. Therefore, reliable SOL and AT stiffness measurements are important for monitoring clinical progress. However, little is known about the absolute reliability of the stiffness measurements of SOL and AT in different ankle positions. This study aimed to determine the absolute reliability of the Young's modulus measurements of the SOL and AT in different ankle positions in healthy young males., Methods: This study included 33 healthy young males. SOL and AT stiffnesses were measured using Young's modulus and shear-wave elastography (SWE). Measurements were taken while the participants were kneeling, with their knees flexed to 90°, and the upper body supported by a table. Ultrasound images were recorded at ankle dorsiflexion angles of -10°, 0°, and 10°. The same measurements were repeated 15 min after the first measurement. Bland-Altman plots were used to verify the type or amount of error and 95 % confidence interval of the minimal detectable change (MDC 95 ) values of the measurements., Results: Bland-Altman plots identified that there was no fixed or proportional bias and that there was good agreement between the first- and second-time measurements of the SOL and AT, respectively, among all angles. The MDC 95 of the Young's modulus of SOL at -10°, 0°, and 10° of ankle dorsiflexion were 5.6 kPa, 7.0 kPa, and 10.1 kPa, respectively, and AT were 15.8 kPa, 16.4 kPa, and 17.8 kPa, respectively., Conclusion: Young's modulus measurements of the SOL and AT using SWE can be used to quantify elastic properties with high confidence. Clinically, assessing changes in the Young's moduli of the SOL and AT using SWE may help determine the effectiveness of interventions., Competing Interests: The authors declare no conflict of interest., (© 2024 Asia Pacific Knee, Arthroscopy and Sports Medicine Society. Published by Elsevier (Singapore) Pte Ltd.)

Herein, we introduce a model of electronic spin isomers, the electronic counterpart of nuclear spin isomers, by using a stable organic diradical. The diradical, composed of two benzotriazinyl radicals connected by a rigid triptycene skeleton, exhibits a small singlet-triplet energy gap of -3.0 kJ/mol, indicating ca. 1:1 coexistence of the two spin states at room temperature. The diradical shows characteristic near-IR absorption bands, which are absent in the corresponding monoradical subunit. Variable temperature measurements revealed that the absorbance of the NIR band depends on the abundance of the singlet state, allowing us to identify the NIR band as the singlet-specific absorption band. It enables photoexcitation of one of the two spin states coexisting in thermal equilibrium. Transient absorption spectroscopy disclosed that the two spin states independently follow qualitatively different excited-state dynamics. These results demonstrate a novel approach to the design and study of electronic spin isomers based on organic diradicals., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

We herein report a method for site-selective photo-crosslinking of a DNA duplex. A stilbene pair was introduced into a DNA duplex and a ruthenium complex was conjugated with a triplex-forming oligonucleotide. We demonstrated that [2+2] photocycloaddition of the stilbene pair occurred upon irradiation with visible light when the ruthenium complex was in close proximity due to triplex formation. No reaction occurred when the ruthenium complex was not in proximity to the stilbene pair. The wavelength of visible light used was of lower energy than the wavelength of UV light necessary for direct excitation of stilbene. Quantum chemical calculation indicated that ruthenium complex catalyzed the photocycloaddition via triplet-triplet energy transfer. Site selectivity of this photo-crosslinking system was evaluated using a DNA duplex bearing two stilbene pairs as a substrate; we showed that the site of crosslinking was precisely regulated by the sequence of the oligonucleotide linked to the ruthenium complex. Since this method does not require orthogonal photoresponsive molecules, it will be useful in construction of complex photoresponsive DNA circuits, nanodevices and biological tools., (© 2024 Wiley‐VCH GmbH.)

The self-assembled state of molecules plays a pivotal role in determining how inherent molecular properties transform and give rise to supramolecular functionalities and has long attracted attention. However, understanding the influence of morphologies spanning the nano- to mesoscopic scales of supramolecular assemblies derived from identical intermolecular interactions has been notoriously challenging due to dynamic structural change and monomer exchange of assemblies in solution. In this study, we demonstrate that curved one-dimensional molecular assemblies (supramolecular polymers) of lengths of around 70-200 nm, originating from the same luminescent molecule, exhibit distinct photoluminescent properties when they form closed circular structures (toroids) versus when they possess chain termini in solution (random coils). By exploiting the difference in kinetic stability between the toroids and random coils, we developed a dialysis protocol to selectively purify the former. It was revealed that these terminus-free closed structures manifest higher energy and more efficient luminescence compared with their mixed state with random coils. Time-resolved fluorescence measurements unveiled that random coils, due to their dynamic structural fluctuation in solution, generate local defects throughout the main chain, leading to luminescence from lower energy levels. In mixtures of the two assemblies, luminescence was exclusively observed from such a lower energy level of random coils, a result attributed to energy transfer between the assemblies. This work emphasizes that for identical supramolecular assemblies, only averaged properties have traditionally been considered, but their structures at the nano- to mesoscopic scale are important especially if they have a certain degree of shape persistency even in solution.

A new synthetic route for constructing functional paddlewheel diruthenium(II,II) complexes ([RuII,II2]) was developed by utilizing Schiff base condensation reactions of formyl-substituted benzoate-bridged [RuII,II2] complexes with various aromatic monoamines under mild conditions. Cyclic voltammetry and DFT calculations revealed that the attached Schiff base groups significantly affected the electronic states of the resulting [RuII,II2] complexes.

The optimal time to ambulation remains unclear for intensive care unit (ICU) patients following abdominal surgery. While previous studies have explored various mobilization techniques, a direct comparison between ambulation and other early mobilization methods is lacking. Additionally, the impact of time to ambulation on complications and disuse syndrome prevention requires further investigation. This study aimed to identify the optimal time to ambulation for ICU patients after abdominal surgery and considered its potential influence on complications and disuse syndrome. We examined the relationship between time to ambulation and hospital length of stay (LOS). Patients were categorized into the nondelayed (discharge within the protocol time) and delayed (discharge later than expected) groups. Data regarding preoperative functioning, postoperative complications, and time to discharge were retrospectively collected and analyzed. Of the 274 postsurgical patients managed in the ICU at our hospital between 2018 and 2020, 188 were included. Time to ambulation was a significant prognostic factor for both groups, even after adjusting for operative time and complications. The area under the curve was 0.72, and the cutoff value for time to ambulation was 22 h (sensitivity, 68%; specificity, 77%). A correlation between time to ambulation and complications was observed, with both impacting the hospital LOS (model 1: p < 0.01, r = 0.22; model 2: p < 0.01, r = 0.29). Specific cutoff values for time to ambulation will contribute to better surgical protocols.

Porous magnets that undergo a magnetic phase transition in response to gaseous adsorbates are desirable for the development of sustainable sensing and memory devices. Familiar gases such as O 2 and CO 2 are one class of target adsorbates because of their close association with life sciences and environmental issues; however, it is not easy to develop magnetic devices that respond to these ubiquitous gases. To date, only three examples of gas-responsive magnetic phase transitions have been demonstrated: (i) from a ferrimagnet to an antiferromagnet, (ii) its vice versa (i.e., change of magnetic phase), and (iii) from a ferrimagnet to a paramagnet (i.e., erasure of the magnetic phase). However, the creation of a magnet, meaning the change from a nonmagnet to a magnet by O 2 or CO 2 gas adsorption and magnetic switching by this phenomenon have not yet been explored. Herein, we report a CO 2 -induced antiferromagnet modified from a paramagnetic charge-flexible layered compound, [{Ru 2 (2,4-F 2 PhCO 2 ) 4 } 2 TCNQ(OEt) 2 ] ( 1 ; 2,4-F 2 PhCO 2 - = 2,4-difluorobenzoate; TCNQ(OEt) 2 = 2,5-diethoxy-7,7,8,8-tetracyanoquinodimethane), where three molar equivalents of CO 2 was accommodated at a CO 2 pressure of 100 kPa. The magnetic change originates from charge fluctuation due to the transfer of electrons moving from the electron-donor to the electron-acceptor unit or vice versa, resulting in a change in the electron distribution induced by CO 2 adsorption/desorption in the donor-acceptor-type charge transfer framework. Owing to the reversible electronic state change upon CO 2 adsorption/desorption, these magnetic phases are switched, accompanied by modification of the electrical conductivity, which is boosted by the CO 2 accommodation. This is the first example of the creation of a CO 2 -responsive magnet, which is promising for novel molecular multifunctional devices.

Partial charge fluctuations in the charge-ordered state of a material, often triggered by structural disorders and/or defects, can significantly alter its physical characteristics, such as magnetic long-range ordering. However, it is difficult to post-chemically fix such accidental partial fluctuations to reconstruct a uniform charge-ordered state. Herein, we report CO 2 -aided charge ordering demonstrated in a CO 2 -post-captured layered magnet, [{Ru 2 (o-ClPhCO 2 ) 4 } 2 {TCNQ(OMe) 2 }] ⋅ CO 2 (1⊃CO 2 ; o-ClPhCO 2 - =ortho-chlorobenzoate; TNCQ(OMe) 2 =2,5-dimethoxy-7,7,8,8-tetracyanoquinodimethane). Pristine porous layered magnet 1 had a partially charge-fluctuated ordered state, which provided ferrimagnetic ordering at T C =65 K. Upon loading CO 2 , 1 adsorbed one mole of CO 2 , forming 1⊃CO 2 , and raising T C to 100 K. This was because of the vanishing charge fluctuations without significantly changing the framework structure. This research illustrates the post-accessible host-guest chemistry delicately combined with charge, spin, and lattice ordering in a spongy magnet. Furthermore, it highlights how this innovative approach opens up new possibilities for technology and nanoscale magnetism manipulation., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

We have demonstrated in the present report that dielectric microparticles exhibited orbital rotation in the light field of non-coaxially configured two counter-propagating laser beams both in numerical simulations and experiments. A series of computational simulations indicated that when irradiated with two non-coaxially counter-propagating parallel laser beams with the same intensity distributions in the absence of thermal (Brownian) motion, a microparticle did not exhibit orbital rotation due to the symmetry of the optical field. However, the computations predicted that a microparticle exhibited one directional orbital rotation in the presence of thermal motion because of the symmetry breaking of the optical force acting on the particle. This spontaneous orbital rotation was experimentally demonstrated for 1-µm dielectric particles in water at room temperature., (© 2023. The Author(s).)

Expression of room-temperature phosphorescence (RTP) in organic materials requires complicated molecular design and specific intermolecular interactions, and therefore types of RTP materials are restricted. This work presents cage-like sodalite-type porous organic salts (s-POSs) as host materials for luminescent molecules to induce RTP, using tetrasulfonic acid with an adamantane core and triphenylmethylamines that are modified with substituents in the para-positions of benzene rings (TPMA-X). By adding a representative luminescent molecule (pyrene) to a reaction solution during construction of s-POSs, the molecule is incorporated in a facile manner. s-POSs with a heavy halogen atom (X: Iodine) on the pore surface give heavy atom effects, suppression of thermal vibration, and protection from oxygen, for the incorporated molecule, which induce its RTP even in air. This strategy can be applied to various luminescent molecules, which may lead to the achievement of RTP of various colors., (© 2023 Wiley-VCH GmbH.)

The resonance between an electronic transition of a micro/nanoscale object and an incident photon flux can modify the radiation force exerted on that object, especially at an interface. It has been theoretically proposed that a non-linear stimulated emission process can also induce an optical force, however its direction will be opposite to conventional photon scattering/absorption processes. In this work, we experimentally and theoretically demonstrate that a stimulated emission process can induce a repulsive pulling optical force on a single trapped dye-doped particle. Moreover, we successfully integrate both attractive pushing (excited state absorption) and repulsive pulling (stimulated emission) resonance forces to control the overall exerted optical force on an object, validating the proposed non-linear optical resonance theory. Indeed, the results presented here will enable the optical manipulation of the exerted optical force with exquisite control and ultimately enable single particle manipulation., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Iron(ii) spin cross-over (SCO) compounds combine a thermally driven transition from the diamagnetic low-spin (LS) state to the paramagnetic high-spin (HS) state with a distinct change in the crystal lattice volume. Inversely, if the crystal lattice volume was modulated post-synthetically, the spin state of the compound could be tunable, resulting in the inverse effect for SCO. Herein, we demonstrate such a spin-state tuning in a breathing cyanido-bridged porous coordination polymer (PCP), where the volume change resulting from guest-induced gate-opening and -closing directly affects its spin state. We report the synthesis of a three-dimensional coordination framework {[Fe II (4-CNpy) 4 ] 2 [W IV (CN) 8 ]·4H 2 O} n (1·4H 2 O; 4-CNpy = 4-cyanopyridine), which demonstrates a SCO phenomenon characterized by strong elastic frustration. This leads to a 48 K wide hysteresis loop above 140 K, but below this temperature results in a very gradual and incomplete SCO transition. 1·4H 2 O was activated under mild conditions, producing the nonporous {[Fe II (4-CNpy) 4 ] 2 [W IV (CN) 8 ]} n (1) via a single-crystal-to-single-crystal process involving a 7.3% volume decrease, which shows complete and nonhysteretic SCO at T 1/2 = 93 K. The low-temperature photoswitching behavior in 1 and 1·4H 2 O manifested the characteristic elasticity of the frameworks; 1 can be quantitatively converted into a metastable HS state after 638 nm light irradiation, while the photoactivation of 1·4H 2 O is only partial. Furthermore, nonporous 1 adsorbed CO 2 molecules in a gated process, leading to {[Fe II (4-CNpy) 4 ] 2 [W IV (CN) 8 ]·4CO 2 } n (1·4CO 2 ), which resulted in a 15% volume increase and stabilization of the HS state in the whole temperature range down to 2 K. The demonstrated post-synthetic guest-exchange employing common gases is an efficient approach for tuning the spin state in breathing SCO-PCPs., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Miyasaka H, Nakagawa Y, Okazaki H, Sonoda S. Influence of sitting posture on anterior buttock sliding during wheelchair propulsion of hemiplegic stroke patients. Jpn J Compr Rehabil Sci 2023; 14: 54-59., Objectives: This study investigated the influence of different sitting postures on wheelchair propulsion ability., Methods: The subjects were stroke patients who scored at least 2 points on the Stroke Impairment Assessment Set for abdominal muscle strength and trunk verticality and 3 points for non-paralytic side lower-limb muscle strength. Moreover, the patients were divided by their everyday wheelchair propulsion posture: Lean on Back Support (LBS); n = 8), those who leaned their back against the back support; and non-LBS ( n = 11), those who moved their back away from the back support. For the wheelchair propulsion method, straight one-hand, one-leg propulsion was used on the non-paralyzed side for 10 m, followed by turning around a target 3 m ahead on each of the paralyzed and non-paralyzed sides. We then compared the propulsion times, number of propulsions, and difference in length from the front end of the patella on the non-paralyzed side to the front end of the seat surface (buttock sliding distance) between the groups., Results: The buttock sliding distance was significantly shorter in the non-LBS group than in the LBS group in the paralyzed and non-paralyzed side turning tasks ( p < 0.05). Propulsion times, number of propulsions, and grip strength did not differ significantly between the groups., Conclusion: Even in patients with good trunk function, propulsion while leaning against the back support can easily result in anterior buttock sliding, leading to a secondary risk of injury. These results suggest that it is necessary to provide guidance on the propulsion posture and seating to hold the trunk vertically to minimize anterior sliding during propulsion., Competing Interests: Conflict of Interest: The authors have no conflict of interest directly relevant to the content of this article., (©Kaifukuki Rehabilitation Ward Association 2023.)

A kinetically-stabilized nitrogen-doped triangulene cation derivative has been synthesized and isolated as the stable diradical with a triplet ground state that exhibits near-infrared emission. As was the case for a triangulene derivative we previously synthesized, the triplet ground state with a large singlet-triplet energy gap was experimentally confirmed by magnetic measurements. In contrast to the triangulene derivative, the nitrogen-doped triangulene cation derivative is highly stable even in solution under air and exhibits near-infrared absorption and emission because the alternancy symmetry of triangulene is broken by the nitrogen cation. Breaking the alternancy symmetry of triplet alternant hydrocarbon diradicals by a nitrogen cation would therefore be an effective strategy to create stable diradicals possessing magnetic properties similar to the parent hydrocarbons but with different electrochemical and photophysical properties., (© 2023 Wiley-VCH GmbH.)

The effects of lipopolysaccharide (LPS) from Rhodobacter sphaeroides , a purple non-sulfur bacterium (PNSB), on the gene expression of the root of rice ( Oryza sativa ) were investigated by next generation sequencing (NGS) RNA-seq analysis. The rice seeds were germinated on agar plates containing 10 pg/mL of LPS from Rhodobacter sphaeroides NBRC 12203 (type culture). Three days after germination, RNA samples were extracted from the roots and analyzed by RNA-seq. The effects of dead (killed) PNSB cells of R. sphaeroides NBRC 12203 T at the concentration of 10 1 cfu/mL (ca. 50 pg cell dry weight/mL) were also examined. Clean reads of NGS were mapped to rice genome (number of transcript ID: 44785), and differentially expressed genes were analyzed by DEGs. As a result of DEG analysis, 300 and 128 genes, and 86 and 8 genes were significantly up- and down-regulated by LPS and dead cells of PNSB, respectively. The plot of logFC (fold change) values of the up-regulated genes of LPS and PNSB dead cells showed a significant positive relationship (r 2 = 0.6333, p < 0.0001), indicating that most of the effects of dead cell were attributed to those of LPS. Many genes related to tolerance against biotic (fungal and bacterial pathogens) and abiotic (cold, drought, and high salinity) stresses were up-regulated, and the most strikingly up-regulated genes were those involved in the jasmonate signaling pathway, and the genes of chalcone synthase isozymes, indicating that PNSB induced defense response against biotic and abiotic stresses via the jasmonate signaling pathway, despite the non-pathogenicity of PNSB.

Background and Objective : Achilles tendon (AT) stiffness can reduce ankle dorsiflexion. However, whether AT stiffness affects the ankle dorsiflexion angle at a maximum squat depth remains unclear. Therefore, we aimed to investigate the relationship between the Young's modulus of the AT and ankle dorsiflexion angle at the maximum squat depth in healthy young males using shear-wave elastography (SWE). Materials and Methods : This cross-sectional study included 31 healthy young males. AT stiffness was measured using the Young's modulus through SWE. The ankle dorsiflexion angle at the maximum squat depth was measured as the angle between the vertical line to the floor and the line connecting the fibula head and the lateral malleolus using a goniometer. Results : Multiple regression analysis identified the Young's modulus of the AT at 10° of ankle dorsiflexion (standardized partial regression coefficient [ β ] = -0.461; p = 0.007) and the ankle dorsiflexion angle in the flexed knee ( β = 0.340; p = 0.041) as independent variables for the ankle dorsiflexion angle at maximum squat depth. Conclusions : The Young's modulus of the AT may affect the ankle dorsiflexion angle at the maximum squat depth in healthy young males. Therefore, improving the Young's modulus of the AT may help increase the ankle dorsiflexion angle at maximum squat depth.

The phenomenon of crystal melting by light irradiation, known as photo-induced crystal-to-liquid transition (PCLT), can dramatically change material properties with high spatiotemporal resolution. However, the diversity of compounds exhibiting PCLT is severely limited, which hampers further functionalisation of PCLT-active materials and the fundamental understandings of PCLT. Here, we report on heteroaromatic 1,2-diketones as the new class of PCLT-active compounds, whose PCLT is based on conformational isomerisation. In particular, one of the diketones demonstrates luminescence evolution prior to crystal melting. Thus, the diketone crystal exhibits dynamic multistep changes in the luminescence colour and intensity during continuous ultraviolet irradiation. This luminescence evolution can be ascribed to the sequential PCLT processes of crystal loosening and conformational isomerisation before macroscopic melting. Single-crystal X-ray structural analysis, thermal analysis, and theoretical calculations of two PCLT-active and one inactive diketones revealed weaker intermolecular interactions for the PCLT-active crystals. In particular, we observed a characteristic packing motif for the PCLT-active crystals, consisting of an ordered layer of diketone core and a disordered layer of triisopropylsilyl moieties. Our results demonstrate the integration of photofunction with PCLT, provide fundamental insights into the melting process of molecular crystals, and will diversify the molecular design of PCLT-active materials beyond classical photochromic scaffolds such as azobenzenes., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)