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The exceptional mechanical flexibility observed with certain organic crystals defies the common perception of single crystals as brittle objects. Here, we describe the morphostructural consequences of plastic deformation in crystals of hexachlorobenzene that can be bent mechanically at multiple locations to 360° with retention of macroscopic integrity. This extraordinary plasticity proceeds by segregation of the bent section into flexible layers that slide on top of each other, thereby generating domains with slightly different lattice orientations. Microscopic, spectroscopic and diffraction analyses of the bent crystal showed that the preservation of crystal integrity when stress is applied on the (001) face requires sliding of layers by breaking and re-formation of halogen–halogen interactions. Application of stress on the (100) face, in the direction where π ··· π interactions dominate the packing, leads to immediate crystal disintegration. Within a broader perspective, this study highlights the yet unrecognized extraordinary malleability of molecular crystals with strongly anisotropic supramolecular interactions. Crystals of hexachlorobenzene easily break when pressed on the (100) face, but bend to 360° without disintegrating when stress is applied on the (001) face. In the latter case this extraordinary malleability arises from the segregation and sliding of layers of molecules in the crystal, a process in which halogen–halogen interactions are broken and reformed.

Molecular crystals are not known to be as stiff as metals, composites and ceramics. Here we report an exceptional mechanical stiffness and high hardness in a known elastically bendable organic cocrystal [caffeine (CAF), 4-chloro-3-nitrobenzoic acid (CNB) and methanol (1:1:1)] which is comparable to certain low-density metals. Spatially resolved atomic level studies reveal that the mechanically interlocked weak hydrogen bond networks which are separated by dispersive interactions give rise to these mechanical properties. Upon bending, the crystals significantly conserve the overall energy by efficient redistribution of stress while perturbations in hydrogen bonds are compensated by strengthened π-stacking. Furthermore we report a remarkable stiffening and hardening in the elastically bent crystal. Hence, mechanically interlocked architectures provide an unexplored route to reach new mechanical limits and adaptability in organic crystals. This proof of concept inspires the design of light-weight, stiff crystalline organics with potential to rival certain inorganics, which currently seem inconceivable.

Chemiluminescence, a process of transduction of energy stored within chemical bonds of ground-state reactants into light via high-energy excited intermediates, is known in solution, but has remained undetected in macroscopic crystalline solids. By detecting thermally induced chemiluminescence from centimeter-size crystals of an organic peroxide here we demonstrate direct transduction of heat into light by thermochemiluminescence of bulk crystals. Heating of crystals of lophine hydroperoxide to ~115 °C results in detectable emission of blue-green light with maximum at 530 nm with low chemiluminescent quantum yield [(2.1 ± 0.1) × 10 ‒7  E mol ‒1 ]. Spectral comparison of the thermochemiluminescence in the solid state and in solution revealed that the solid-state thermochemiluminescence of lophine peroxide is due to emission from deprotonated lophine. With selected 1,2-dioxetane, endoperoxide and aroyl peroxide we also establish that the thermochemiluminescence is common for crystalline peroxides, with the color of the emitted light varying from blue to green to red. Chemiluminescence is known in solution, but has remained undetected in macroscopic crystalline solids so far. Here the authors demonstrate direct transduction of heat into light by thermochemiluminescence in a centimeter-size lophine hydroperoxide crystal.

Although airway management is important in pediatric resuscitation, the effectiveness of bag-mask ventilation (BMV) and advanced airway management (AAM), such as endotracheal intubation (ETI) and supraglottic airway (SGA) devices, for prehospital resuscitation of pediatric out-of-hospital cardiac arrest (OHCA) remains unclear. We aimed to determine the efficacy of AAM during prehospital resuscitation of pediatric OHCA cases. We searched four databases from their inception to November 2022 and included randomized controlled trials and observational studies with appropriate adjustments for confounders that evaluated prehospital AAM for OHCA in children aged <18 years in quantitative synthesis. We compared three interventions (BMV, ETI, and SGA) via network meta-analysis using the GRADE Working Group approach. The outcome measures were survival and favorable neurological outcomes at hospital discharge or 1 month after cardiac arrest. Five studies (including one clinical trial and four cohort studies with rigorous confounding adjustment) involving 4852 patients were analyzed in our quantitative synthesis. Compared with ETI, BMV was associated with survival (relative risk [RR] 0.44 [95% confidence intervals (CI) 0.25–0.77]) (very low certainty). There were no significant association with survival in the other comparisons (SGA vs. BMV: RR 0.62 [95% CI 0.33–1.15] [low certainty], ETI vs. SGA: RR 0.71 [95% CI 0.39–1.32] [very low certainty]). There was no significant association with favorable neurological outcomes in any comparison (ETI vs. BMV: RR 0.33 [95% CI 0.11–1.02]; SGA vs. BMV: RR 0.50 [95% CI 0.14–1.80]; ETI vs. SGA: RR 0.66 [95% CI 0.18–2.46]) (all very low certainty). In the ranking analysis, the hierarches for efficacy for survival and favorable neurological outcome were BMV > SGA > ETI. Although the available evidence is from observational studies and its certainty is low to very low, prehospital AAM for pediatric OHCA did not improve outcomes. •Network meta-analysis improves the detection power and accuracy by synthesizing direct and indirect comparisons.•Prehospital advanced airway management for pediatric OHCA does not improve outcomes.•Most of the available evidence was from observational studies.

Lewy bodies (LBs) and glial cytoplasmic inclusions (GCIs) are specific aggregates found in Parkinson’s disease (PD) and multiple system atrophy (MSA), respectively. These aggregates mainly consist of α-synuclein (α-syn) and have been reported to propagate in the brain. In animal experiments, the fibrils of α-syn propagate similarly to prions but there is still insufficient evidence to establish this finding in humans. Here, we analysed the protein structure of these aggregates in the autopsy brains of patients by synchrotron Fourier-transform infrared micro-spectroscopy (FTIRM) analysis without extracting or artificially amplifying the aggregates. As a result, we found that the content of the β-sheet structure in LBs in patients with PD was significantly higher than that in GCIs in patients with MSA (52.6 ± 1.9% in PD vs. 38.1 ± 0.9% in MSA, P  < 0.001). These structural differences may provide clues to the differences in phenotypes of PD and MSA.

Molecular crystals are not known to be as stiff as metals, composites and ceramics. Here we report an exceptional mechanical stiffness and high hardness in a known elastically bendable organic cocrystal [caffeine (CAF), 4-chloro-3-nitrobenzoic acid (CNB) and methanol (1:1:1)] which is comparable to certain low-density metals. Spatially resolved atomic level studies reveal that the mechanically interlocked weak hydrogen bond networks which are separated by dispersive interactions give rise to these mechanical properties. Upon bending, the crystals significantly conserve the overall energy by efficient redistribution of stress while perturbations in hydrogen bonds are compensated by strengthened π -stacking. Furthermore we report a remarkable stiffening and hardening in the elastically bent crystal. Hence, mechanically interlocked architectures provide an unexplored route to reach new mechanical limits and adaptability in organic crystals. This proof of concept inspires the design of light-weight, stiff crystalline organics with potential to rival certain inorganics, which currently seem inconceivable. Molecular crystals are typically less stiff than metals or ceramics. Here the authors report an organic elastically bendable co-crystal with stiffness comparable to low-density metals, hardness similar to stainless steel and reveal the molecular mechanism which lead to these mechanical properties.

Spin liquid (SL) systems have been the subject of much attention recently, as they have been theoretically predicted to not freeze, even at 0 K. Despite extensive searches being made for such a system, only a few candidates have been found. All of these candidates share geometrical frustrations that are based on triangular lattices. We applied vibrational spectroscopy to one of the candidates of a molecule-based SL system, and we compared its results against three antiferromagnetic compounds and four charge-ordered compounds. All of their structural motifs belong to triangular lattices. The C=C stretching modes in the SL state indicated that there were charge and lattice fluctuations. These fluctuations were suppressed but non-negligible in the AF compounds. This finding is potentially significant, as it indicates that a hidden lattice and charge fluctuation are the driving force of a geometrical frustration, which eventually leads to a SL state.

We analyzed edible potato starch and observed the interaction between its granular structure and water molecules. We studied the changes caused by gelatinization during heating and stirring using microscopy, micro‐FT‐IR spectroscopy, and X‐ray scattering techniques. A wide range of spatial scales was revealed using these various techniques. The rate of gelatinization varied significantly and was dependent on the starch concentration. The process of adsorption of water on starch molecules was studied using the humidity‐controlled FT‐IR spectroscopy technique. Furthermore, by comparing the X‐ray scattering profiles of dry and wet granules, the 9‐nm repeat “cluster” structure was studied. A gradual collapse of the granules occurred during the processes of heating and stirring. A clustered smectic structure and a smectic‐like structure were observed in the opaque gel after gelatinization. Upon further heating, a transparent gel was obtained after the melting of the cluster. We analyzed edible potato starch and observed the interaction between its granular structure and water molecules. A wide range of spatial scales was revealed using various techniques such as X‐ray scattering and FT‐IR measurements. We could succeed gelatinization and gelation process with a wide spatial scale.

Autosomal recessive primary microcephaly 5 (MCPH5) is caused by pathogenic variants in ASPM. Using whole-exome sequencing, we diagnosed two siblings with MCPH5. A known pathogenic variant (NM_018136.4: c.9697C > T, p.(Arg3233*)) and a novel pathogenic variant (c.1402_1406del, p.(Asn468Serfs*2)) of ASPM were identified in affected siblings with normal intelligence. Their pathogenic variants were not located in the critical regions of ASPM, but the relationship between the genotypes and their normal intelligence was unclear.