Atomically precise photothermal nanomachines.

Interfacing molecular machines to inorganic nanoparticles can, in principle, lead to hybrid nanomachines with extended functions. Here we demonstrate a ligand engineering approach to develop atomically precise hybrid nanomachines by interfacing gold nanoclusters with tetraphenylethylene molecular rotors. When gold nanoclusters are irradiated with near-infrared light, the rotation of surface-decorated tetraphenylethylene moieties actively dissipates the absorbed energy to sustain the photothermal nanomachine with an intact structure and steady efficiency. Solid-state nuclear magnetic resonance and femtosecond transient absorption spectroscopy reveal that the photogenerated hot electrons are rapidly cooled down within picoseconds via electron-phonon coupling in the nanomachine. We find that the nanomachine remains structurally and functionally intact in mammalian cells and in vivo. A single dose of near-infrared irradiation can effectively ablate tumours without recurrence in tumour-bearing mice, which shows promise in the development of nanomachine-based theranostics.

Rational Design of 2D Metal Halide Perovskites with Low Congruent Melting Temperature and Large Melt-Processable Window.

Metal halide perovskites (MHPs) have garnered significant attention due to their distinctive optical and electronic properties, coupled with excellent processability. However, the thermal characteristics of these materials are often overlooked, which can be harnessed to cater to diverse application scenarios. We showcase the efficacy of lowering the congruent melting temperature (Tm) of layered 2D MHPs by employing a strategy that involves the modification of flexible alkylammonium through N-methylation and I-substitution. Structural-property analysis reveals that the N-methylation and I-substitution play pivotal roles in reducing hydrogen bond interactions between the organic components and inorganic parts, lowering the rotational symmetry number of the cation and restricting the residual motion of the cations. Additional I···I interactions enhance intermolecular interactions and lead to improved molten stability, as evidenced by a higher viscosity. The 2D MHPs discussed in this study exhibit low Tm and wide melt-processable windows, e.g., (DMIPA)2PbI4 showcasing a low Tm of 98 °C and large melt-processable window of 145 °C. The efficacy of the strategy was further validated when applied to bromine-substituted 2D MHPs. Lowering the Tm and enhancing the molten stability of the MHPs hold great promise for various applications, including glass formation, preparation of high-quality films for photodetection, and fabrication of flexible devices.

Molecular Engineering Regulation Achieving Out-of-Plane Polarization in Rare-Earth Hybrid Double Perovskites for Ferroelectrics and Circularly Polarized Luminescence.

Out-of-plane polarization is a highly desired property of two-dimensional (2D) ferroelectrics for application in vertical sandwich-type photoferroelectric devices, especially in ultrathin ferroelectronic devices. Nevertheless, despite great advances that have been made in recent years, out-of-plane polarization remains unrealized in the 2D hybrid double perovskite ferroelectric family. Here, from our previous work 2D hybrid double perovskite HQERN ((S3HQ)4EuRb(NO3)8, S3HQ = S-3-hydroxylquinuclidinium), we designed a molecular strategy of F-substitution on organic component to successfully obtain FQERN ((S3FQ)4EuRb(NO3)8, S3FQ = S-3-fluoroquinuclidinium) showing circularly polarized luminescence (CPL) response. Remarkably, compared to the monopolar axis ferroelectric HQERN, FQERN not only shows multiferroicity with the coexistence of multipolar axis ferroelectricity and ferroelasticity but also realizes out-of-plane ferroelectric polarization and a dramatic enhancement of Curie temperature of 94 K. This is mainly due to the introduction of F-substituted organic cations, which leads to a change in orientation and a reduction in crystal lattice void occupancy. Our study demonstrates that F-substitution is an efficient strategy to realize and optimize ferroelectric functional characteristics, giving more possibility of 2D ferroelectric materials for applications in micro-nano optoelectronic devices.

Probing the local structure of FLiBe melts and solidified salts by in situ high-temperature NMR.

The 2LiF-BeF2 (FLiBe) salt melt is considered the primary choice for a coolant and fuel carrier for the generation IV molten salt reactor (MSR). However, the basics of ionic coordination and short-range ordered structures have been rarely reported due to the toxicity and volatility of beryllium fluorides, as well as the lack of suitable high-temperature in situ probe methods. In this work, the local structure of FLiBe melts was investigated in detail using the newly designed HT-NMR method. It was found that the local structure was comprised of a series of tetrahedral coordinated ionic clusters (e.g., BeF42-, Be2F73-, Be3F104-, and polymeric intermediate-range units). Li+ ions were coordinated by BeF42- ions and the polymeric Be-F network through the analysis of the NMR chemical shifts. Using solid-state NMR, the structure of solid FLiBe solidified mixed salts was confirmed to form a 3D network structure, significantly similar to those of silicates. The above results provide new insights into the local structure of FLiBe salts, which verifies the strong covalent interactions of Be-F coordination and the specific structural transformation to the polymeric ions above 25% BeF2 concentration.

SENP5 deteriorates traumatic brain injury via SUMO2-dependent suppression of E2F1 SUMOylation.

Traumatic brain injury (TBI) represents a main public health concern during the past decade, attracting considerable interest because of its rising prevalence, wide-ranging risk factors and lifelong familial and societal influence. SUMO2 can conjugate to substrates upon various cellular stresses. Nevertheless, whether and how SUMO2-specific proteases partake in TBI is less understood. The aim of this study is to dissect the effects of SUMO-specific peptidase 5 (SENP5) on accentuating TBI in rats in an effort to unveil its underlying mechanism. SENP5 is overexpressed in hippocampal tissues of TBI rats, and inhibition of SENP5 reduces neurological function scores, decreases brain water content, inhibits apoptosis in hippocampal tissues, and attenuates brain injury caused in rats. Moreover, SENP5 inhibits the SUMOylation level of E2F transcription factor 1 (E2F1) and increases the protein expression of E2F1. Silencing of E2F1 blocks the p53 signaling pathway. Overexpression of E2F1 partially reverses the protective effect of sh-SENP5 on TBI in rats. These findings reveal an essential role of SENP5 and the SUMOylation status of E2F1 in the TBI development.

A Powder Self-Healable Hydrogel Electrolyte for Flexible Hybrid Supercapacitors with High Energy Density and Sustainability.

Ionic conductive hydrogel electrolyte is considered to be an ideal electrolyte candidate for flexible supercapacitor due to its flexibility and high conductivity. However, due to the lack of effective recycling methods, a large number of ineffective flexible hydrogel supercapacitors caused by some irreversible damages and dryness of hydrogel electrolyte are abandoned, which would induce heavy economic and environmental protection problems. Herein,a smart ionic conductive hydrogel (SPMA-Zn: ZnSO4 /sodium alginate/polymethylacrylic acid) is developed for flexible hybrid supercapacitor (SPMA-ZHS). The SPMA-Zn exhibits an excellent self-healing ability and can recover its electrochemical performance after multiple mechanical damages. More importantly, it possesses an outstanding powder self-healable property, which could easily regenerate the hydrogel electrolyte after powdering, and maintain stable electrochemical performance of SPMA-ZHS. Besides, the SPMA-ZHS displays excellent electrochemical performance with a wide and stable working voltage range of 0-2.2 V, high energy density of 164.13 Wh kg-1 at the power density of 1283.44 Wh kg-1 and good stability with a capacity retention of 95.3% after 5000 charge/discharge cycles at 10 A g-1 . The strategy in this work would provide a new insight in exploring flexible hydrogel electrolyte-based supercapacitor with good sustainability and high energy density for flexible wearable electronic devices.

NMR study on the cellulose dissolution mechanism in CaCl2·6H2O-LiCl molten salt hydrate.

As there is a rising interest in upgrading cellulose to high-performance bio-products, the studies on innovative reaction media and processes have been leaping forward. Green solvents in terms of cellulose dissolution and brief processes for upgrading are critical to green chemistry. However, most solvent systems generally exhibit defects in harsh pH operating windows with limited temperature ranges, environmental pollution, long reaction times, complicated processes, etc. In this work, we have provided a novel molten salt hydrate (CaCl2·6H2O-LiCl) as a green solvent and investigated the role of hydrated molten salts in the dissolution process via the solid state nuclear magnetic resonance (NMR) technique. The cellulose could be dissolved in CaCl2·6H2O-LiCl molten salt hydrated at 120 °C with 3.0% solubility and regenerated in-situ by cooling down to ambient temperature. The regenerated cellulose exhibited a high solubility and excellent stability. From 7Li single pulse NMR experiments, it was observed that two types of Li+ existed in the cellulose dissolution, and the Li+ significantly impacted the dissolving process and the dissolution ability of cellulose. This work would provide an environmental-friendly strategy to prepare cellulose solutions for biocompatible cellulose materials.

Deuterated Covalent Organic Frameworks with Significantly Enhanced Luminescence.

Luminescent covalent organic frameworks (COFs) find promising applications in chemical sensing, photocatalysis, and optoelectronic devices, however, the majority of COFs are non or weakly emissive owing to the aggregation-caused quenching (ACQ) or the molecular thermal motion-based energy dissipation. Here, we report a previously unperceived approach to improve luminescence performance of COFs by introducing isotope effect, which is achieved through substitution of hydrogen from high-frequency oscillators X-H (X=O, N, C) by heavier isotope deuterium. Combining the "bottom-up" and in situ deuteration methods generates the first deuterated COF, which exhibits an impressively 19-fold enhancement in quantum yield over that of the non-deuterated counterpart. These results are interpreted by theoretical calculations as the consequence of slower C/N-D and OD⋅⋅⋅O vibrations that impede the nonradiative deactivation process. The proposed strategy is proved applicable to many other types of emissive COFs.

Donepezil protects glycerol-induced acute renal failure through the cholinergic anti-inflammatory and nitric oxide pathway in rats.

OBJECTIVES: Inflammation as well as oxygen metabolite play important roles in renal injury during pathogenesis of rhabdomyolysis induced myoglobinuric acute renal failure (ARF). The aim of this study was to investigate the protective effects of donepezil on immune responses in rats with glycerol-induced ARF. METHODS: Sixty male rats were randomly divided into six groups, the rats were given normal saline (10 ml/kg, i.m.), glycerol (50%, 10 ml/kg, i.m.), glycerol plus dexamethasone (0.1 mg/kg, i.g.), and glycerol plus donepezil (1, 5 and 10 mg/kg, i.g.) respectively. After two weeks of glycerol injections, the kidney tissues and blood samples were harvested for future biochemical and pathology analysis. The levels of creatinine (Cr) and urea nitrogen (BUN) in plasma, the content of malondialdehyde (MDA), glutathione (GSH), and superoxide dismutase (SOD) activity, total nitric oxide synthase (TNOS), inducible nitric oxide synthase (iNOS), endothelial NO synthase (eNOS) were evaluated in renal tissues. In addition, interleukin-6 (IL-6), tumor necrosis factors-α (TNF-α) in renal tissues were also determined. RESULTS: Donepezil treatment protected rats from renal dysfunction in a dose-dependent manner and through the cholinergic anti-inflammatory pathway. Additionally, donepezil significantly reduced tubular damages, prevented neutrophil infiltration and decreased productions of the IL-6, TNF-α, nitric oxide content and oxidative damage. CONCLUSIONS: These data indicate that donepezil exerts a protective anti-inflammatory effect during ARF through the cholinergic pathway and Nitric oxide pathway. In addition, this study could provide an opportunity to overcome the effect of surgical cholinergic denervation during kidney transplantation and other injury.

Semiconducting 2D Triazine-Cored Covalent Organic Frameworks with Unsubstituted Olefin Linkages.

Establishing an sp2-carbon-bonding pattern is one of the efficient accesses to various organic semiconducting materials. However, the less-reversible carbon-carbon bond formation makes it still challenging to spatially construct a well-defined organic framework with π-extended two-dimensional (2D) structure through solution process. Here, a Knoevenagel condensation approach to synthesize two new 2D covalent organic frameworks (COFs) connected by unsubstituted carbon-carbon double bond linkages through activating the methyl carbons of a 2,4,6-trimethyl-1,3,5-triazine monomer is presented. The resulting sp2-carbon-linked triazine-cored 2D sheets are vertically stacked into high-crystalline honeycomb-like structures, endowing this kind of COF with extended π-delocalization, tunable energy levels, as well as high surface areas, regular open channels, and chemical stabilities. On the other hand, their microfibrillar morphologies allow for the facile manipulation of thin films as photoelectrodes without additive. Accordingly, such kinds of COF-based photoelectrodes exhibit photocurrents up to ∼45 µA cm-2 at 0.2 V vs RHE as well as rapid charge transfer rates, in comparison with imine-linked COF-based photoelectrodes. In addition, both COFs are applicable for conducting photocatalytic hydrogen generation from water splitting by visible-light irradiation.

Preoperative systemic inflammation score (SIS) is superior to neutrophil to lymphocyte ratio (NLR) as a predicting indicator in patients with esophageal squamous cell carcinoma.

BACKGROUND: The aim of this study was to assess the prognostic significance of preoperative systemic inflammation score (SIS) on patients with esophageal squamous cell carcinoma (ESCC). METHODS: A total of 357 ESCC patients who accepted radical esophagectomy between January 2008 and December 2009 at our institution were recruited in the analysis. The cut-off finder application was used to calculate the optimal cutoff values. The Chi-squared test or Fisher's exact test were used to analyze categorical variables. Overall survival (OS) was calculated using the Kaplan-Meier method and the log-rank test. Multivariate analysis was calculated using Cox regression analysis model. A model combining SIS was created and its performance was evaluated using the Akaike information criterion (AIC) and concordance index (C-index). RESULTS: The median follow-up time was 58 months (range, 1-84 months). The 5-year OS rate was 50% (95% CI, 49.94-50.06%). The optimal cut-off values for preoperative neutrophil to lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR) and serum albumin (Alb) were 2.27, 3.79 and 36.55, respectively. Univariate analyses revealed that gender (P = 0.047), T stage (P < 0.001), N stage (P < 0.001), vascular invasion (P < 0.001), tumor location (P = 0.018), tumor length(P < 0.001), NLR (P = 0.006), LMR (P = 0.007), serum Alb (P = 0.001), and SIS (P < 0.001) were significantly associated with OS. Independent prognostic factors for OS were T stage, N stage, tumor location, tumor length, and SIS. However, NLR was not an independent prognostic factor in multivariate analysis. The model combining SIS had smaller AIC and higher C-index compared to the model without SIS, which suggesting that the adding the SIS to the multivariate model increasing the predictive accuracy of the OS in the ESCC patients treated with radical esophagectomy and 3-field lymphadenectomy (3-FL). CONCLUSIONS: SIS may treat as a novel prognostic factor than NLR for ESCC patients who underwent radical esophagectomy and 3-FL. However, Larger-scale studies are needed to validate these findings.

Donepezil Attenuates Obesity-Associated Oxidative Stress and Central Inflammation and Improves Memory Deficit in Mice Fed a High-Fat Diet.

BACKGROUND/AIMS: Obesity is associated with chronic inflammation and cognitive decline, and is considered a major risk factor for neurodegeneration. Meanwhile, neuroinflammation is important in the pathogenesis and progression of neurodegenerative diseases. METHODS: In this study, we tested the hypothesis that donepezil would attenuate central inflammation and oxidative damage and improve memory deficit in high-fat diet (HFD)-fed mice. After 16 weeks on a HFD, C57BL/6J mice were given either donepezil (3 mg/kg, i.p.) or saline for 4 weeks in parallel to a control diet (CD) group. Thereafter, the step-through test was used to assess learning and memory function. RESULTS: In the brain of HFD-fed mice, levels of the proinflammatory cytokines interleukin 16 and tumor necrosis factor α were reduced by donepezil treatment. Similarly, HFD-induced protein levels of advanced glycation end-products and oxidative stress in the brain were significantly decreased by donepezil treatment. CONCLUSION: Our results indicate that donepezil may reverse obesity-related central inflammation and oxidative damage and improve memory deficit in HFD-fed mice.

A Small Lattice Change Induces Significant Dynamic Changes of CH3NH3+ Caged in Hybrid Perovskite Crystals: Toward Understanding the Interplay between Host Lattices and Guest Molecules.

Two perovskite-type compounds, (MA)2[B'Co(CN)6] (MA = methylammonium, B' = K(I) and Na(I)), have very similar structures, but exhibit marked differences in the phase and dielectric transitions. Solid state 2H NMR studies reveal the detailed dynamic changes of the caged methylammonium (MA) cations before and after the phase transitions, which are correlated with the different dielectric states of the compounds. Using solid state 59Co NMR, the dynamic changes of the host lattices before and after the transitions, which accompany the changes in the dynamics of the caged MA cations, are unveiled, demonstrating the intriguing interplay between the MA cations and the host lattices. On the basis of these observations, the molecular origins of the dielectric transitions are discussed in detail.

Fast Lithium-Ion Transportation in Crystalline Polymer Electrolytes.

Fast lithium-ion transportation is found in the crystalline polymer electrolytes, α-CD-PEOn /Li+ (n=12, 40), prepared by self-assembly of α-cyclodextrin (CD), polyethylene oxide (PEO) and Li+ salts. A detailed solid-state NMR study combined with the X-ray diffraction technique reveals the unique structural features of the samples, that is, a) the tunnel structure formed by the assembled CDs, providing the ordered long-range pathway for Li+ ion transportation; b) the all-trans conformational sequence of the PEO chains in the tunnels, attenuating significantly the coordination between Li+ and the EO segments. The origin of the fast lithium-ion transportation has been attributed to these unique structural features. This work demonstrates the first example in solid polymer electrolytes (SPEs) for "creating" fast ion transportation through material design and will find potential applications in the design of new ionconducting SPE materials.

Functional Characteristics, Electrophysiological and Antennal Immunolocalization of General Odorant-Binding Protein 2 in Tea Geometrid, Ectropis obliqua.

As one of the main lepidopteran pests in Chinese tea plantations, Ectropisobliqua Warren (tea geometrids) can severely decrease yields of tea products. The olfactory system of the adult tea geometrid plays a significant role in seeking behaviors, influencing their search for food, mating partners, and even spawning grounds. In this study, a general odorant-binding protein (OBP) gene, EoblGOBP2, was identified in the antennae of E. obliqua using reverse transcription quantification PCR (RT-qPCR). Results showed that EoblGOBP2 was more highly expressed in the antennae of males than in females relative to other tissues. The recombinant EoblGOBP2 protein was prepared in Escherichia coli and then purified through affinity chromatography. Ligand-binding assays showed that EoblGOBP2 had a strong binding affinity for some carbonyl-containing tea leaf volatiles (e.g., (E)-2-hexenal, methyl salicylate, and acetophenone). Electrophysiological tests confirmed that the male moths were more sensitive to these candidate tea plant volatiles than the female moths. Immunolocalization results indicated that EoblGOBP2 was regionally confined to the sensilla trichoid type-II in the male antennae. These results indicate that EoblGOBP2 may be primarily involved in the olfactory activity of male E. obliqua moths, influencing their ability to sense tea leaf volatiles. This study provides a new perspective of insect GOBPs and implies that olfactory function can be used to prevent and control the tea geometrid.

Exhaled Nitric Oxide Is Useful in Symptomatic Radioactive Pneumonia: A Retrospective Study.

The aim was to defect the exhaled nitric oxide (eNO) prediction value of symptomatic radioactive pneumonia (SRP). 64 cases of lung cancer or esophagus cancer, who had the primary radiotherapy (intensity-modulated radiation therapy), were included from 2015 June to 2016 January. During the following, the patients were divided: the symptomatic radiation pneumonia group (SRP, with the CTCAE v4.0 score > 2) and the asymptomatic radiation pneumonia group (ASRP, with CTCAE v4.0 score ≤ 1). All the patients were measured eNO before and at the end of thoracic radiotherapy and gain the posttherapy eNO value and the eNO ratio (posttherapy eNO value/pretherapy eNO value), then the predictive values of eNO toward SRP were measured using the receiver-operating characteristic (ROC). 17 cases were included in the SRP group and the other 47 were included in the ASRP group. The posttherapy eNO was 29.35 (19~60) bbp versus 20.646 (11~37) (P < 0.001), and the ratio was 1.669 (0.61~3.5) versus 0.920 (0.35~1.5) (P < 0.01) (symptomatic versus asymptomatic). ROC showed that the cutoff value of SRP was 19.5 bbp (posttherapy eNO, area under concentration-time curve (AUC) = 0.879) and 1.305 (eNO ratio, AUC = 0.774), which meant that posttherapy eNO and eNO ratio were useful in finding SRP.

Ionic conductivity of ß-cyclodextrin-polyethylene-oxide/alkali-metal-salt complex.

Highly conductive, crystalline, polymer electrolytes, ß-cyclodextrin (ß-CD)-polyethylene oxide (PEO)/LiAsF6 and ß-CD-PEO/NaAsF6 , were prepared through supramolecular self-assembly of PEO, ß-CD, and LiAsF6 /NaAsF6 . The assembled ß-CDs form nanochannels in which the PEO/X(+) (X=Li, Na) complexes are confined. The nanochannels provide a pathway for directional motion of the alkali metal ions and, at the same time, separate the cations and the anions by size exclusion.

HT-NMR Studies of the Be-F Coordination Structure in FNaBe and FLiBe Mixed Salts.

Molten NaF-BeF2 salt is widely considered a promising candidate to replace FLiBe in molten salt reactor applications, which is crucial to reducing the operating costs of the molten salt reactor. Studies on beryllium compounds are rarely conducted due to their volatility and high toxicity. Herein, the Be-F coordination structure of NaF/BeF2 mixed salts was investigated in-depth through various HT-NMR and solid-state NMR methods, which are optimized to be appropriate for the detection of beryllium compounds. It was found that Na2BeF4 and NaBeF3 crystals were transformed into amorphous tetrahedral coordinated networks when there was an increase in the BeF2 concentration in the mixed salts. The main coordinate structure comparisons between FNaBe and FLiBe were analyzed, which exhibit high similarity due to the covalent effect of Be-F bonding, demonstrating the theoretical feasibility of applying FNaBe salts as a substitute for FLiBe in MSR systems. In addition, the transition from the crystal phase to the amorphous phase occurred at a lower BeF2 concentration for FNaBe than that for FLiBe. This was further verified by the results of ab initio molecular dynamics (AIMD) simulation that FNaBe melts had more disordered structures, thus causing slight changes in their physical properties.

L-citrulline protects against glycerol-induced acute renal failure in rats.

There is an increasing evidence that oxidative stress plays an important role in the pathogenesis of rhabdomyolysis-induced acute renal failure (ARF). In this study, protective effects of L-citrulline on glycerol-induced ARF in rats were investigated. Six groups of rats were employed in this study: group 1 served as a control; group 2 was only given glycerol (50%, 10 mL/kg, i.m.); group 3 was given glycerol plus dexamethasone (0.1 mg/kg, i.g.) as positive reference drug, starting at the same time as the glycerol injections; the last three groups were given glycerol plus L-citrulline (300, 600, and 900 mg/kg, i.g.) respectively, starting at the same time as the glycerol injections. The injections of glycerol were only once, and after glycerol injections the i.g. administrations of dexamethasone and L-citrulline were repeated every 24 h for 7 days. After 7 days of glycerol injections, the blood samples and kidney tissues were harvested for future biochemical and pathology analyses. The levels of creatinine (Cr) and urea nitrogen (BUN) in plasma, the content of malondialdehyde (MDA), glutathione (GSH), nitric oxide (NO), the activity of total nitric oxide synthase (TNOS), inducible nitric oxide synthase (iNOS), endothelial NO synthase (eNOS), and superoxide dismutase (SOD) were evaluated in kidney tissues. Consequently, administrations of L-citrulline improved an impaired intrarenal oxygenation and kidney function compared with the glycerol group, and prevented the renal oxidative stress damage as well as severe functional and morphological renal deterioration. Therefore, L-citrulline might have potential application in the amelioration of glycerol-induced ARF.