Search

This study aimed at examining how romantically involved Chinese young adults' dysfunctional individuation was associated with their and their partners' perceptions of romantic relationship satisfaction. We recruited 296 Chinese couples who were currently in heterosexual romantic relationships at the university. The couples completed self‐report measures of their dysfunctional individuation and relationship satisfaction. Results from the cross‐sectional actor–partner interdependence model (APIM) indicated that (a) for both genders, actor effects existed: Chinese young adults' dysfunctional individuation was negatively associated with their romantic relationship satisfaction; (b) in terms of partners' effects, women's dysfunctional individuation was negatively associated with men's perceptions of relationship satisfaction; but (c) men's dysfunctional individuation was not significantly associated with women's perceptions of relationship satisfaction. The findings were the first to reveal the actor and partner effects of dysfunctional individuation on romantic relationship satisfaction. The study results provided practical implications regarding how young adults can have satisfying romantic relationships. [ABSTRACT FROM AUTHOR]

Aim: With industrialization and spread of the westernized lifestyle, the number of people affected by non‐alcoholic fatty liver disease (NAFLD)/non‐alcoholic steatohepatitis (NASH) is growing rapidly in China; this has become a major public health concern. To better understand the burden and characteristics of NAFLD/NASH in China, we aim to perform a narrative review of the literature published in this field. Materials and Methods: We carried out a comprehensive electronic search of five English‐language and three Chinese‐language databases, to identify studies regarding NAFLD or NASH published from inception to November 30, 2022. Epidemiological studies of NAFLD/NASH in China were particularly noticed and summarized. We also searched the www.clinicaltrials.gov and www.chictr.org.cn websites for the registered trials on the treatment of the disease led by Chinese investigators or located in China. Results: The increasing rate of NAFLD prevalence in China is strikingly high, reaching more than twice that in western countries. The prevalence of NAFLD is nearly 30% of the general Chinese population, making it the leading cause of chronic liver diseases. The prevalence of NAFLD/NASH varies between provinces/regions, age groups, sexes, and individuals with different metabolic profiles. NAFLD co‐exists in many Chinese patients with chronic hepatitis B. Since 2020, more Chinese studies have used the term metabolic‐associated fatty liver disease (MAFLD), emphasizing the underlying metabolic disorders that occur concurrently with this disease. Several clinical trials involving lifestyle interventions, antidiabetic drugs, or traditional Chinese medicines, registered by Chinese investigators, have been completed or are ongoing. Moreover, several innovative targeted therapies developed in China are revolutionizing the treatment of NAFLD/NASH. Conclusions: NAFLD has cast a heavy burden on the Chinese healthcare system. Chinese scholars are making efforts to achieve the optimal management of this disease. [ABSTRACT FROM AUTHOR]

Chrysin (CHR) is a flavonoid with extensive pharmacological activity. The molecular formula of CHR is C15H10O4. CHR is reported to have antioxidative, antitumour and antiviral functions. To evaluate its potential function as a vaccine adjuvant, we prepared a melanoma vaccine using a soluble protein extract of B16F10 melanoma cells as antigen and CHR as an adjuvant. The melanoma model was developed after two immunizations, and it was discovered that combining B16F10 soluble protein antigen‐mixed CHR vaccine could inhibit tumour growth in the mouse model, and the overall survival rate was higher than that of the B16F10 antigen vaccine alone. In vivo and in vitro experiments were conducted to determine whether CHR functioned as an adjuvant by activating antigen‐presenting cells (APCs). We discovered that CHR activated APCs both in vivo and in vitro and may enhance Th1 cell function by activating the IL12‐STAT4 signal pathway, thereby enhancing the antitumour response of cytotoxic T lymphocytes (CTLs) in vivo. Next, to verify the critical role of CD8+ T cells in suppressing melanoma development, we transplanted CD8+ T cells from immunized mice to B16F10 tumour‐bearing mice and discovered that the survival rate of tumour‐bearing mice was significantly prolonged. In summary, our experimental results indicate that CHR can be used as a potential adjuvant to enhance antigen immunogenicity, inhibit B16F10 tumour growth in mice and improve tumour immune response. [ABSTRACT FROM AUTHOR]

Metabolic syndrome (MetS) is a major public health burden worldwide and associated with brain abnormalities. Although insulin resistance is considered a pivotal feature of MetS, its role in the pathogenesis of MetS‐related brain alterations in the general population is unclear. Therefore, in 973 participants (mean age 52.5 years) of the population‐based Rhineland Study, we assessed brain morphology in relation to MetS and insulin resistance, and evaluated to what extent the pattern of structural brain changes seen in MetS overlap with those associated with insulin resistance. Cortical reconstruction and volumetric segmentation were obtained from high‐resolution brain images at 3 Tesla using FreeSurfer. The relations between metabolic measures and brain structure were assessed through (generalized) linear models. Both MetS and insulin resistance were associated with smaller cortical gray matter volume and thickness, but not with white matter or subcortical gray matter volume. Age‐ and sex‐adjusted vertex‐based brain morphometry demonstrated that MetS and insulin resistance were related to cortical thinning in a similar spatial pattern. Importantly, no independent effect of MetS on cortical gray matter was observed beyond the effect of insulin resistance. Our findings suggest that addressing insulin resistance is critical in the prevention of MetS‐related brain changes in later life. [ABSTRACT FROM AUTHOR]

A series of novel monodisperse, structurally well defined vinylene‐linked phenothiazine oligomers containing up to 7 phenothiazine units have been designed and synthesized by Heck reaction and McMurry reaction with a convergent approach. These conjugated oligomers showed a progressive bathochromic shift of the absorption maxima and high fluorescence quantum yields in solutions. Notably, the oligomers without strong donor and acceptor units exhibit two‐photon absorption properties, and the two‐photon absorption cross sections (δ) increase with the number of covalently linked phenothiazine units, and δ reaches up to 2071 GM for the one with 7 phenothiazine units at 800 nm. The oligomers might be used as models to study structure–property relationship for their corresponding polymers or applied in organic electronic materials. [ABSTRACT FROM AUTHOR]

Fluorescent organic molecules with C3-symmetry consisting of tris{2-cyano-2-[4-(dodecyloxybenzoylamino)phenyl]-1-ethenyl}phenylbenzene (CN-DBAPPBn, n = 1, 2, 3) were synthesized. It was observed that these compounds can spontaneously self-assemble into organogels in many organic solvents. Scanning electron microscopy (SEM), light microscopy, and fluorescence microscopy images of the air-dried gels showed the presence of either heavily entangled amorphous or fibrous structures, or rods. FTIR, UV/Vis absorption, excitation and emission spectra suggest that π-π interactions and H-bonding are the driving forces for the formation of the gel phases. Moreover, spherical or cubic fluorescent nanoparticles based on CN-DBAPPBn were prepared by using a reprecipitation method in a mixture of tetrahydrofuran and water. It is interesting that aggregation-induced emission behavior of CN-DBAPPBn was detected in both the gel phase and in the nanoparticle suspensions. The fluorescent molecular aggregates of CN-DBAPPBn with different architectures and emission properties fabricated by using these self-assembling methods could find potential applications in sensors and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the ability of propolis‐coated ureteric stents to solve complications, especially urinary tract infections (UTIs) and crusting, in patients with long‐term indwelling ureteric stents through antimicrobial and anti‐calculus activities. Materials and Methods: Polyurethane (PU) ureteric stents were immersed in the ethanol extract of propolis (EEP), a well‐known antimicrobial honeybee product, and subjected to chemical, hydrophilic, and seismic tests. The antimicrobial activity of the EEP coating was then examined by in vitro investigation. Proteus mirabilis infection was induced in rats within uncoated and EEP‐coated groups, and the infection, stone formation, and inflammation were monitored at various time points. Results: The characterisation results showed that the hydrophilicity and stability of the EEP surface improved. In vitro tests revealed that the EEP coating was biocompatible, could eliminate >90% of bacteria biofilms attached to the stent and could maintain bacteriostatic properties for up to 3 months. The in vivo experiment revealed that the EEP‐coating significantly reduced the amount of bacteria, stones, and salt deposits on the surface of the ureteric stents and decreased inflammation in the host tissue. Conclusions: Compared with clinically used PU stents, EEP‐coated ureteric stents could better mitigate infections and prevent encrustation. Thus, this study demonstrated that propolis is a promising natural dressing material for ureteric stents. [ABSTRACT FROM AUTHOR]

Structurally ordered soft materials that respond to complementary stimuli are susceptible to control over their spatial and temporal morphostructural configurations by intersectional or combined effects such as gating, feedback, shape‐memory, or programming. In the absence of general and robust design and prediction strategies for their mechanical properties, at present, combined chemical and crystal engineering approaches could provide useful guidelines to identify effectors that determine both the magnitude and time of their response. Here, we capitalize on the purported ability of soft intermolecular interactions to instigate mechanical compliance by using halogenation to elicit both mechanical and photochemical activity of organic crystals. Starting from (E)‐1,4‐diphenylbut‐2‐ene‐1,4‐dione, whose crystals are brittle and photoinert, we use double and quadruple halogenation to introduce halogen‐bonded planes that become interfaces for molecular gliding, rendering the material mechanically and photochemically plastic. Fluorination diversifies the mechanical effects further, and crystals of the tetrafluoro derivative are not only elastic but also motile, displaying the rare photosalient effect. [ABSTRACT FROM AUTHOR]

Structurally ordered soft materials that respond to complementary stimuli are susceptible to control over their spatial and temporal morphostructural configurations by intersectional or combined effects such as gating, feedback, shape‐memory, or programming. In the absence of general and robust design and prediction strategies for their mechanical properties, at present, combined chemical and crystal engineering approaches could provide useful guidelines to identify effectors that determine both the magnitude and time of their response. Here, we capitalize on the purported ability of soft intermolecular interactions to instigate mechanical compliance by using halogenation to elicit both mechanical and photochemical activity of organic crystals. Starting from (E)‐1,4‐diphenylbut‐2‐ene‐1,4‐dione, whose crystals are brittle and photoinert, we use double and quadruple halogenation to introduce halogen‐bonded planes that become interfaces for molecular gliding, rendering the material mechanically and photochemically plastic. Fluorination diversifies the mechanical effects further, and crystals of the tetrafluoro derivative are not only elastic but also motile, displaying the rare photosalient effect. [ABSTRACT FROM AUTHOR]

Background: Modified titanium substrates with titanium dioxide nanotubes have broad usage as implant surface treatment and as drug- delivery systems. Their performance in most of these applications is highly dependent on there morphology. Macrophage behavior was thought to be regulated by nanostructured titanium which has been considered as a very promising candidates for dental implants. Aim/Hypothesis: To investigate effects of hydrogenated TiO2 nanotubes on macrophage behavior, secretion and expression of pro- inflammatory cytokines and chemokines. Material and Methods: Macrophage- like J744A.1 cells were cultured on three types of Ti surface- hydrogenated TiO2 nanotubes, unmodified TiO2 nanotubes, and Ti substrates (as control) for 4, 24 and 48 hours. Macrophage adhesion and proliferation were assessed using CCK-8 assay. Levels of pro-inflammatory cytokines (TNF- a, IL- 1b and IL- 6) and chemokines (MCP-1 and MIP-1a) secreted into the supernatant were measured using the Cytometric Bead Arrays kit. TNF-a, MCP-1 and MIP- a gene expression were quantitatively analysed by real- time PCR. Results : These show that TiO2 nanotube surfaces, especially hydrogenated TiO2 nanotubes, benefited macrophage adhesion and prolifera-tion, and reduced protein secretion and mRNA expression of pro- inflammatory cytokines and chemokines. Conclusions and Clinical Implications : TiO2 nanotube surfaces, especially hydrogenated TiO2 nanotubes, reduced inflammatory response in vitro, which might induce rapid osseointegration in implants with hydrogenated TiO2 nanotube surfaces in vivo. [ABSTRACT FROM AUTHOR]

Generally, the potential reactive "olefin pairs" in the molecular crystals satisfying Schmidt's criteria could undergo topological [2+2] cycloaddition. In this study, another factor that affects the photodimerization reactivity of chalcone analogues was found. The cyclic chalcone analogues of (E)‐2‐(2,4‐dichlorobenzylidene)‐2,3‐dihydro‐1H‐inden‐1‐one (BIO), (E)‐2‐(naphthalen‐2‐ylmethylene)‐2,3‐dihydro‐1H‐inden‐1‐one (NIO), (Z)‐2‐(2,4‐dichlorobenzylidene)benzofuran‐3(2H)‐one (BFO), and (Z)‐2‐(2,4‐dichlorobenzylidene)benzo[b]thiophen‐3(2H)‐one (BTO) have been synthesized. While the geometrical parameters for the molecular packing of the above four compounds did not exceed Schmidt's criteria, [2+2] cycloaddition did not occur in the crystals of BIO and BTO. The single crystal structures and Hirshfeld surface analyses revealed that interactions of C=O⋅⋅⋅H (CH2) existed between adjacent molecules in the crystal of BIO. Therefore, the carbonyl and methylene groups linked with one carbon atom in carbon‐carbon double bond were tightly confined in the lattice, acting as a tweezer to inhibit free movement of the double bond and suppressing [2+2] cycloaddition. In the crystal of BTO, similar interactions of Cl⋅⋅⋅S and C=O⋅⋅⋅H (C6H4) prevented free movement of the double bond. In contrast, the intermolecular interaction of C=O⋅⋅⋅H only exists around the carbonyl group in the crystals of BFO and NIO, leaving the C=C double bonds to move freely and allowing the occurrence of [2+2] cycloaddition. Driven by photodimerization, the needle‐like crystals of BFO and NIO displayed evident photo‐induced bending behavior. This work demonstrates that the intermolecular interactions around carbon‐carbon double bond affect the [2+2] cycloaddition reactivity except for Schmidt's criteria. These findings provide valuable insights into the design of photomechanical molecular crystalline materials. [ABSTRACT FROM AUTHOR]

Three groups of chalcone derivatives and their analogues involving halogen atoms (X=F, Cl, Br) have been synthesized. Firstly, the nearly planar acyclic chalcone derivatives were inclined to undergo photo‐induced stereospecific [2+2] cycloaddition, which triggered the crystals to exhibit macroscopic motions of bending or cracking. In particular, the single‐crystal‐to‐single‐crystal transformation happened upon UV irradiation of the crystals, which was helpful for the understanding photomechanical effects. Cyclic 3,4‐dihydronaphthalene‐based chalcone analogues possess a more twisted conformation, and they tend to undergo trans‐cis isomerization. No photomechanical effect was observed for the crystals of the cyclic chalcone analogues due to the lower isomerization rate. The twist degree of chroman‐based molecules was in between of the first two, [2+2] cycloaddition and trans‐cis isomerization simultaneously took place in crystals. Photo‐induced bending and twisting were observed for the crystals of chroman‐based chalcone analogues. Therefore, the differences in molecular dihedral angles in α,β‐unsaturated ketones were responsible for their photochemical characters and in turn to tune the photomechanical effects. In this work, a bridge between the molecular structures and solid‐state photochemical reactions triggered photomechanical crystals is built. [ABSTRACT FROM AUTHOR]

BACKGROUND This research compared four new apple selections with 16 established apples using descriptive analysis ( DA), instrumental analyses and preference mapping, in order to identify suitable selections for commercialization and further research. RESULTS DA revealed that the new apple selections ( PARC1, PARC2, PARC3, PARC4) were very similar in texture/mouthfeel (T) but differed in their flavor (F) and appearance (A) characteristics. Preference mapping revealed that consumers' T preferences were driven primarily by crispness, juiciness and lack of skin toughness, while F preferences were driven by sweetness, lack of tartness and presence of fruity flavor. Consumers' A preferences were driven by a high percentage of red color and degree of striping. The majority of consumers had similar T (82-85%) and F (88-92%) preferences for the early- and mid/late-harvest apples. In contrast, consumers' A preferences were differentiated into three subgroups (60%, 24%, 16%) for the early-harvest apples, but not for the mid/late-harvest apples. The new apple selections were among those most liked for T, F and A. CONCLUSION This early-stage consumer research confirmed that the new apples were comparable, if not superior, to the established apples. As such, it provided the necessary feedback to industry to proceed with commercialization and optimization of cultural and storage practices. © 2015 Her Majesty the Queen in Right of Canada Journal of the Science of Food and Agriculture © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The photomechanical effects of crystals of halogen‐substituted 9‐anthracenecarbonitrile were investigated. The needle‐like crystals of 10‐fluoroanthracene‐9‐carbonitrile (FCNA) bend rapidly under irradiation with 365 nm, 410 nm light and even white light, and the bent crystal could almost recover to its original shape upon exposure to 254 nm light or heating. The reversible photo‐induced mechanical behaviors originated from [4+4] cycloaddition and the reverse reaction. This type of photoactuator, in response to light irradiation over a broad wavelength range from UV to the visible region, might have important applications in biomimetic systems, biomedicine, artificial muscles, and smart microrobotics. The rapid photo‐induced mechanical movements of the crystals inspired us to fabricate a hybrid polymer film of polyvinylidene difluoride incorporated with the microcrystals of FCNA, which not only showed bending toward or away from the light source depending on the initial bending direction of the film, but also could lift small objects induced by remote light. [ABSTRACT FROM AUTHOR]

The polymorphs of 2ClChMe‐4 in Form I (ribbon‐like crystal) and Form II (block‐like crystal) were prepared, and they exhibited curling/flipping and expansion upon heating on account of single‐crystal‐to‐single‐crystal transformations. The irreversible phase transformations occurred separately at 53.2 °C and 57.8 °C for the crystals in Form I and Form II, during which the molecular conformation of 2ClChMe‐4 changed and the molecules slipped along the (100) plane. Movement at the molecular level resulted in changes of cell parameters, which in turn led to macroscopic motions of the crystals upon heating. Additionally, the ribbon‐like crystals of 2ClChMe‐4 showed photo‐induced bending driven by [2+2] cycloaddition. Accordingly, an actuator showing reversible bending behavior was fabricated triggered by light and heat successively. Like biomimetic self‐actuators, such multi‐stimuli mechanical responsive molecular crystals might have potential applications in soft robots, artificial muscles and microfluidic systems. [ABSTRACT FROM AUTHOR]

The phloem, located within the vascular system, is critical for delivery of nutrients and signaling molecules throughout the plant body. Although the morphological process and several factors regulating phloem differentiation have been reported, the molecular mechanism underlying its initiation remains largely unknown. Here, we report that the small peptide‐coding gene, CLAVATA 3 (CLV3)/EMBEYO SURROUNDING REGION 25 (CLE25), the expression of which begins in provascular initial cells of 64‐cell‐staged embryos, and continues in sieve element‐procambium stem cells and phloem lineage cells, during post‐embryonic root development, facilitates phloem initiation in Arabidopsis. Knockout of CLE25 led to delayed protophloem formation, and in situ expression of an antagonistic CLE25G6T peptide compromised the fate‐determining periclinal division of the sieve element precursor cell and the continuity of the phloem in roots. In stems of CLE25G6T plants the phloem formation was also compromised, and procambial cells were over‐accumulated. Genetic and biochemical analyses indicated that a complex, consisting of the CLE‐RESISTANT RECEPTOR KINASE (CLERK) leucine‐rich repeat (LRR) receptor kinase and the CLV2 LRR receptor‐like protein, is involved in perceiving the CLE25 peptide. Similar to CLE25, CLERK was also expressed during early embryogenesis. Taken together, our findings suggest that CLE25 regulates phloem initiation in Arabidopsis through a CLERK‐CLV2 receptor complex. [ABSTRACT FROM AUTHOR]

Spirofluorene‐cored bis(difluoroboron β‐diketonate) complexes bearing terminal carbazoles (CbzBSF) and tert‐butylcarbazoles (TCbzBSF) have been synthesized. It was found that only TCbzBSF could form organogels in cyclohexane and methylcyclohexane, suggesting that tert‐butylcarbazole was essential for its organogelation directed by weak π–π interactions. It is worth noting that TCbzBSF could entrap ca. 5800 molecules of methylcyclohexane per gelator molecule, so this fully conjugated complex without traditional gelation group could be considered as a supergelator. The gained organogel showed reversible thixotropic and temperature‐dependent sol‐gel transitions. In particular, the orange red fluorescence of the xerogel‐based film of TCbzBSF could be quenched when exposed to gaseous aromatic amines of aniline, N‐methylaniline, and N,N‐dimethylaniline. The detection limit for aniline vapor of the xerogel‐based film was as low as 0.56 ppb. [ABSTRACT FROM AUTHOR]

Abstract: An alkoxyl radical guided strategy for site‐selective functionalization of unactivated methylene and methine C−H bonds enabled by an FeII‐catalyzed redox process is described. The mild, expeditious, and modular protocol allows efficient remote aliphatic fluorination, chlorination, amination, and alkynylation of structurally and electronically varied primary, secondary, and tertiary hydroperoxides with excellent functional‐group tolerance. The application for one‐pot 1,4‐hydroxyl functionalization of non‐oxygenated alkane substrates initiated by aerobic C−H oxygenation is also demonstrated. [ABSTRACT FROM AUTHOR]

Abstract: An alkoxyl radical guided strategy for site‐selective functionalization of unactivated methylene and methine C−H bonds enabled by an FeII‐catalyzed redox process is described. The mild, expeditious, and modular protocol allows efficient remote aliphatic fluorination, chlorination, amination, and alkynylation of structurally and electronically varied primary, secondary, and tertiary hydroperoxides with excellent functional‐group tolerance. The application for one‐pot 1,4‐hydroxyl functionalization of non‐oxygenated alkane substrates initiated by aerobic C−H oxygenation is also demonstrated. [ABSTRACT FROM AUTHOR]

Abstract: New diarylethene derivatives containing benzoxazole (NBO) and benzothiazole (NBT) have been synthesized. Light‐induced trans–cis isomerization of NBO and NBT took place in crystals, and only induced the needle‐like crystals of NBO to bend backwards away from the UV light source. The movement of the atoms was deemed to take place during the isomerization of NBO; hence, strain would be produced and accumulated rapidly in the surface of crystals exposed to UV light. The uniform release of strain led to the bending of needle‐like crystals. The light‐induced trans–cis isomerization efficiency of NBT was too low to drive the motion of crystals, which might have originated from the large repulsion between naphthyl and benzothiazole. These results provide a new platform for the transformation of light energy into mechanical energy in molecular crystals through the unimolecular photochemical reaction of diarylethene derivatives. [ABSTRACT FROM AUTHOR]

Novel luminescent organogelators based on nucleoside functionalized with carbazole (UC8, UC12 and UC16) were designed and synthesized. Their gelation ability was tested and it was found that both UC12 and UC16 could form stable organogels in toluene/petroleum ether. The UV-vis absorption, fluorescence emission and IR spectral changes during the gelation of UC12 proved that the self-assembly was driven by H- bonding. The morphology of the xerogel UC16 obtained from toluene/petroleum ether (v/v = 1/1) displayed tough rod-like microstructures, and 3D networks formed from lots of nanofibers were observed for the xerogel UC16 obtained from toluene/petroleum ether (v/v = 2/1). It was interesting that the obtained organogels emitting blue light could be destroyed by the addition of F-, accompanied with the declining the emission intensity. Therefore, these organogels could be used as sensory materials to recognize F-. [ABSTRACT FROM AUTHOR]

Aims: To perform a meta‐analysis of randomized controlled trials (RCTs), including 6 recently published large‐scale cardiovascular outcome trials (CVOTs), to evaluate the risk of pancreatic cancer with incretin‐based therapies in patients with type 2 diabetes (T2DM). Materials and Methods: For the period January 1, 2007 to May 1, 2017, the PubMed, Embase, Cochrane Central Register and ClininalTrials.gov databases were searched for RCTs in people with T2DM that compared incretin drugs with placebo or other antidiabetic drugs, with treatment and follow‐up durations of ≥52 weeks. Two reviewers screened the studies, extracted the data and assessed the risk of bias independently and in duplicate. Results: A total of 33 studies (n = 79 971), including the 6 CVOTs, with 87 pancreatic cancer events were identified. Overall, the pancreatic cancer risk was not increased in patients administered incretin drugs compared with controls (Peto odds ratio [OR] 0.67, 95% confidence interval [CI] 0.44‐1.02). In the 6 CVOTs, 79 pancreatic cancer events were identified in 55 248 participants. Pooled estimates of the 6 CVOTs showed an identical tendency (Peto OR 0.65, 95% CI 0.42‐1.01). Notably, in the subgroup of participants who received treatment and follow‐up for ≥104 weeks, 84 pancreatic cancer events were identified in 59 919 participants, and a lower risk of pancreatic cancer was associated with incretin‐based therapies (Peto OR 0.62, 95% CI 0.41‐0.95). Conclusions: Treatment with incretin drugs was not associated with an increased risk of pancreatic cancer in people with T2DM. Instead, it might protect against pancreatic malignancy in patients treated for ≥104 weeks. [ABSTRACT FROM AUTHOR]

We report interesting photomechanical behaviors of the dynamic molecular crystals of ( E)-2-(2,4-dichlorostyryl)benzo[d]oxazole ( BOACl24). The photosalient effect of the rod-like crystal based on a metal-free olefin driven by photodimerization is observed. Moreover, the needle-like crystals of BOACl24 exhibit a reversible bending away from a UV light source. The nanofibers curl easily under UV irradiation in an organogel, in which the photo-induced rolling of a small slice occurs. This suggests that the rapid release of the accumulated strain during photodimerization may lead to a photosalient effect, and the bending or curling happens when the strain is released slowly. Notably, [2+2] cycloaddition takes place between two different conformational isomers of BOACl24 on account of the rotation of the benzoxazole ring around the C−C bond in an excited state before photodimerization. Such topo-photochemical reaction has not been reported elsewhere. [ABSTRACT FROM AUTHOR]

We report interesting photomechanical behaviors of the dynamic molecular crystals of (E)-2-(2,4-dichlorostyryl)benzo[d]oxazole (BOACl24). The photosalient effect of the rod-like crystal based on a metal-free olefin driven by photodimerization is observed. Moreover, the needle-like crystals of BOACl24 exhibit a reversible bending away from a UV light source. The nanofibers curl easily under UV irradiation in an organogel, in which the photo-induced rolling of a small slice occurs. This suggests that the rapid release of the accumulated strain during photodimerization may lead to a photosalient effect, and the bending or curling happens when the strain is released slowly. Notably, [2+2] cycloaddition takes place between two different conformational isomers of BOACl24 on account of the rotation of the benzoxazole ring around the C−C bond in an excited state before photodimerization. Such topo-photochemical reaction has not been reported elsewhere. [ABSTRACT FROM AUTHOR]

We have synthesized a series of new β-iminoenolates and their corresponding difluoroboron complexes without any traditional gelation moieties, and some of them were able to gelatinize organic solvents. It was found that the presence of halogen atoms as substituents had a significant effect on gelation ability. In particular, bromo-containing compounds 4 A and 4 B exhibited excellent gelation abilities compared with other halogen-substituted gelators. By analyses of the single-crystal structure, the PXRD pattern of the xerogel, and electronic spectral changes during gelation, we deemed that π-π, C−H⋅⋅⋅F, and C−H⋅⋅⋅Br interactions were the driving forces for the gelation of 4 B. Interestingly, ( Z)-1-(4-bromophenyl)-2-(3-methylpyrazin-2-yl)ethen-1-ol ( 8 A), prepared in this work, is the lowest-molecular-weight organogelator to have been reported. It should be noted that although β-iminoenolates 3 A- 5 A are nonemissive in solution, they emit strong yellow light in organogels, which suggests aggregation-induced emissive activity, whereas the difluoroboron complexes 3 B- 5 B show strong fluorescence in solutions, organogels, and xerogel-based films. Moreover, we found that the emission of 4 B in a nanofiber-based film could be quenched significantly upon exposure to gaseous trifluoroacetic acid and that the decay time and detection limit were 0.5 s and 0.17 ppm, respectively. Thus, through this work we have provided a new strategy for the design of nontraditional π gelators by introducing halogen atoms into π-conjugated systems with moderate polarities. [ABSTRACT FROM AUTHOR]

An L-phenylalanine derivative ( C12PhBPCP) consisting of a strong emission fluorophore with benzoxazole and cyano groups is designed and synthesized to realize dual responses to volatile acid and organic amine vapors. The photophysical properties and self-assembly of the said derivative in the gel phase are also studied. C12PhBPCP can gelate organic solvents and self-assemble into 1 D nanofibers in the gels. UV/Vis absorption spectral results show H-aggregate formation during gelation, which indicates strong exciton coupling between fluorophores. Both wet gel and xerogel emit strong green fluorescence because the cyano group suppresses fluorescence quenching in the self-assemblies. Moreover, the xerogel film with strong green fluorescence can be used as a dual chemosensor for quantitative detection of volatile acid and organic amine vapors with fast response times and low detection limits owing to its large surface area and amplified fluorescence quenching. The detection limits are 796 ppt and 25 ppb for gaseous aniline and trifluoroacetic acid (TFA), respectively. [ABSTRACT FROM AUTHOR]

Nanofibers based on phenanthroimidazole derivatives PCC, PDC, and PSC were fabricated by organogelation processes, and their fluorescence sensory properties towards acid were investigated. It was found that the emission of PCC in the nanofiber-based film could be quenched significantly upon exposure to gaseous TFA due to the formation of protonated PCC, in which ICT (intramolecular charge transfer) would occur. On the other hand, TFA vapor led to the emitting colors of PDC and PSC in the nanofiber-based films to turn to yellow and green from sky blue and blue, respectively. Additionally, we found that the decay times of PCC were 0.1 s and 1.9 s in probing the saturated vapor of TFA in nanofiber-based film and in spin-coated film, respectively. The results suggested that the high surface-to-volume ratio and large interspace in the nanofiber-based networks favored the enhanced adsorption, accumulation, and diffusion of gaseous molecules, resulting in such a high performance. [ABSTRACT FROM AUTHOR]

Two L-phenylalanine derivatives with 5,8-bis(2-(carbazol-3-yl)vinyl)quinoxaline ( PCQ) and 5,8-bis[2-(carbazol-3-yl)]-2,3-dimethylquinoxaline ( DCQ) as fluorophores were synthesized, and their photophysical properties were measured and compared. The two compounds were found to gelate some organic solvents and self-assemble into 1D nanofibers in gels. The wet gel of PCQ emitted a weak orange fluorescence, but the DCQ gel had a strong green one. This result can be due to the presence of two methyl groups and the nonplanar conformation of fluorophore in DCQ. The gel film of DCQ also showed significantly stronger fluorescence than that of PCQ. Thus, the wet gel and xerogel film of DCQ were selected to study their sensing properties to acids. The yellow wet gel of DCQ transformed into a brown sol upon the addition of 0.2 equiv trifluoroacetic acid (TFA), accompanied by emission quenching. The xerogel film of DCQ rapidly responded to volatile acids, such as TFA, HCl, and HOAc. The fluorescence of the xerogel film was gradually quenched with increased concentration of volatile acid vapors. The fibrous film exhibited low detection limits for volatile acid. The detection limits of the thin films for TFA, HCl, and HOAc reached 43, 122, and 950 ppb, respectively. [ABSTRACT FROM AUTHOR]

The simplest carbazole-based organogelator C1 (9-hexadecyl-9 H-carbazole) has been synthesized and can self-assemble into nanofibers in the gel phase directed by balanced π-π interactions. To extend the conjugation of the π gelator, we prepared linear carbazole-based trimer C3 and pentamer C5, which also exhibited gelation behavior in some organic solvents upon ultrasound stimulation. It is found that the xerogel of C3 emits strong blue light under UV irradiation. Notably, the emission of C3 in nanofiber-based films can be quenched upon exposure to vapors of TNT and DNT. The steady-state Stern-Volmer plots of C3 in toluene revealed that the fluorescent quenching induced by aromatic nitro compounds is due to photoinduced electron transfer. Therefore the emitting nanofibers fabricated from linear carbazole by organogelation can be used as fluorescent sensors to detect explosives. [ABSTRACT FROM AUTHOR]

We study the photophysical characters of two oligofluorenes-functionalized anthracenes molecules with different fluorine-vinylene ( FV) units, which exhibits that 'excimer' state appears in the solution after photoexcitation. The dynamic data shows that two mechanisms are responsible for the generation of 'excimer'. The fast one is controlled by the arene-arene interaction between molecules and the slow one is influenced by the diffusion motion of molecules. Increasing the number of FV units may suppress the DM-dependent 'excimer' and enhance the yield of intrinsic fluorescence, which finally improves the fluorescence property of molecules in solution. [ABSTRACT FROM AUTHOR]

The effects of π-spacer and electron donor groups on the photophysical behaviors of fluorenone-based linear conjugated oligomers have been systemically investigated. Solvent-dependent steady-state measurements exhibit that the fluorene vinylene ( FV) spacer and the electron-donating ability of donor group are able to modulate the spectral features of oligomers and the fluorescence quantum yield could decrease with the increasing of the solvent polarity. Meanwhile, quantum chemical calculation simulates their absorption spectra, and analyzes their electron transition components simultaneously. The transient absorption measurements focus on the photoexcitation dynamics of these oligomers in the toluene solution, which show that an intramolecular charge transfer state exists in the relaxation process of excited states, and its generation process could accelerate with the introduction of FV spacer and the enhancement of donor strength. [ABSTRACT FROM AUTHOR]

Background : Modified titanium substrates with titanium dioxide nanotubes have broad usage as implant surface treatment and drug delivery system. Their performance in most of these application is highly dependent on their morphology, nanotube dimension, and wettability. Aim/Hypothesis : To improve the drug-loading capacity and accelerate bone integration with titanium, in this study, we hydrogenated anodized titanium dioxide nanotubes (TNTs) by a thermal treatment. Material and Methods: Three groups were examined, namely- hydrogenated TNTs (H2-TNTs, test), unmodified TNTs (air- TNTs, control), and Ti substrates (Ti control). Results : Our results showed that oxygen vacancies were present in all the nanotubes. The quantity of -OH groups greatly increased after hydrogenation. Furthermore, the protein adsorption and loading capacity of the H2- TNTs were considerably enhanced as compared with the properties of the air-TNTs ( P < 0.05). Additionally, time-of-flight secondary ion mass spectrometry (TOF- SIMS) was used to investigate the interactions of TNTs with proteins. During the protein- loading process, the H2- TNTs not only enabled rapid protein adsorption, but also decreased the rate of protein elution compared with that of the air-TNTs. We found that the H2-TNTs exhibited better biocompatibility than the air-TNT and Ti groups. Both cell adhesion activity and alkaline phosphatase activity were significantly improved toward MG-63 human osteoblast-like cells as compared with the control groups (P < 0.05). Conclusions and Clinical Implications : Therefore, we conclude that hydrogenated TNTs can greatly improve the loading capacity of bioactive molecules and MG-63 cell proliferation. [ABSTRACT FROM AUTHOR]