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Tumor recurrence and unfavorable bacterial biofilm formation on implants after bone tumor resection remain challenging in clinical settings. However, this dilemma also provides inspiration for the development of bioactive implants and a new route for the management of bone tumors through biofilm formation. Here, based on the characteristic that bacteria prefer to adhere to implants, 3D‐printing bioceramic scaffolds modified with probiotic biofilms are designed to augment antitumor immunity. In comparison with Akkermansia muciniphila, Lactobacillus rhamnosus GG (LGG) is demonstrated to more easily form biofilms on bioceramics and is selected to engineer etched bioceramics. The LGG biofilm subjected to pasteurization guarantees good biocompatibility and enhanced doxorubicin (Dox) loading. Furthermore, the LGG biofilm combined with Dox imparts the scaffolds with multiple properties of direct chemo‐killing for tumor cells and potent immune activation. The modified scaffolds efficiently inhibit bone tumor recurrence and bone metastasis in murine tumor model receives surgical resection. Moreover, based on 3D‐printing technology, the probiotic biofilm modified scaffolds with adjustable shapes are also demonstrated to repair shape‐specific bone defects after tumor elimination. Collectively, the multifunctional 3D‐printing scaffolds realize the integrated treatment of tumor elimination and bone repair, providing a promising strategy for clinical treatment of bone tumors. [ABSTRACT FROM AUTHOR]

Macrocyclic molecule‐based host–guest systems, which provide contributions for the design and construction of functional supramolecular structures, have gained increasing attention in recent years. In particular, platinum(II) metallacycle‐based host–guest systems provide opportunities for chemical scientists to prepare novel materials with various functions and structures due to the well‐defined shapes and cavity sizes of platinum(II) metallacycles. However, the research on platinum(II) metallacycle‐based host–guest systems has been given little attention. In this article, we demonstrate the host–guest complexation between a platinum(II) metallacycle and a polycyclic aromatic hydrocarbon molecule, naphthalene. Taking advantage of metallacycle‐based host–guest interactions and the dynamic property of reversible Pt coordination bonds, a [2]rotaxane is efficiently prepared by employing a template‐directed clipping procedure. The [2]rotaxane is further applied to the fabrication of an efficient light‐harvesting system with multi‐step energy transfer process. This work comprises an important supplement to macrocycle‐based host–guest systems and demonstrates a strategy for efficient production of well‐defined mechanically interlocked molecules with practical values. [ABSTRACT FROM AUTHOR]

Volatile radioactive pollutants are posing great challenges to global environment. Volatile radioactive iodine, which is one of the primary environmental pollutants from nuclear power plants, spreads rapidly in water and air and increases risk to human health. Therefore, the research for appropriate adsorbents to capture iodine with long‐term storage is crucial. In this study, we report that easily obtained fluorinated leaning pillar[6]arene FP6 is a new adsorbent for iodine capture with robust moisture and thermal stability. Crystalline solid FP6 solid can capture not only volatile iodine in the air but also iodine dissolved in aqueous solutions with fast adsorption speed and high up‐take capacity. Host–guest interactions between FP6 and iodine indicates that iodine molecule is threaded into the cavity of the cyclic host FP6 to form a host‐guest complex driven by C−F ⋅⋅⋅ I halogen bonding interactions. Moreover, the regeneration of FP6 is simple and efficient, and it can be regenerated at least five times by simply heating under vacuum at 120 °C for 3 hours without losing iodine capture capacity. The excellent iodine pollutant removal ability demonstrates the promise of FP6 for pollutant treatment. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The construction of multi‐responsive supramolecular systems for drug delivery is a challenging task. In this work, a Pd2L4 metallacage 1·([BF4]−)4 with four pyrene units was first designed and synthesized through coordination‐driven self‐assembly. After the introduction of γ‐CD, a supramolecular amphiphile 1–γ‐CD was successfully constructed based on the host–guest molecular recognition between γ‐CD and the pyrene unit of 1·([BF4]−)4, which further self‐assembled into dual‐responsive supramolecular vesicles in aqueous solution. DOX·HCl was used as a model molecule to study the drug encapsulation and release behavior of the supramolecular vesicles. By adjusting the pH of the solution to acidic condition or adding a certain amount of α‐amylase, the vesicle structure was destroyed to achieve rapid and effective release of the drug molecules. This study provides an example for the rational design of efficient dual‐responsive supramolecular nanocarriers, which have potential application value in the field of controlled drug delivery. [ABSTRACT FROM AUTHOR]

The dewetting damage of solid propellant under loading is a key factor affecting the constitutive properties of solid propellant, and it will weaken structural integrity of solid rocket motor charge. The quantitative characterization of its evolution process has always been a very active research field. In this study, a nonlinear ultrasonic (NLU) method is proposed to investigate and monitor in real‐time the nonlinear dynamic response of solid propellant. The NLU parameter, which can evolve dewetting damage, is expressed by some physical quantities such as the frequency peak, the propagation distance and so on, and is recorded at different strain in the tensile tests of the round rod solid propellant specimens. Then, the initial dewetting point, characteristic dewetting point and characteristic dewetting rate are defined to characterize the dewetting performance. The results show that NLU parameter changes continuously with the evolution of tensile process and increases sharply at the initial dewetting damage point. By analyzing the data, an empirical formula characterizing the variation law of NLU parameter with strain is proposed, which is well fitted to the experimental data under different strain rates. In addition, relevant numerical simulation is carried out, and the simulation results verify the feasibility of the NLU method. [ABSTRACT FROM AUTHOR]

Since the growing importance of phenazine derivatives, the efficient synthetic strategies for the preparation of phenazine derivatives have attracted great attention from organic methodology. Herein, we comprehensively review and summarize a series of sustainable and facile synthetic strategies of phenazine derivatives. Moreover, we further discuss the approach of preparation and the superiority of each strategy. [ABSTRACT FROM AUTHOR]

Aspartic acid and glutamic acid show critical impact in the central nervous system as excitatory neurotransmitters. The selective detection of aspartic acid and glutamic acid has a wide range of potential applications in the field of biomedicine. In this work, we report the highly selective detection of L‐Aspartic acid (L‐Asp) and L‐Glutamic acid (L‐Glu) in water is achieved by using a fluorescent nanoparticle constructed by a water‐soluble pillar[5]arene‐based host‐guest interactions. These nanoparticles show strong fluorescent emission in water. After the addition of L‐Asp or L‐Glu to a solution of the fluorescent nanoparticles, these nanoparticles transformed to nanosheets with weak fluorescent emission, resulting the highly selective detection of aspartic acid and glutamic acid in water. The detection limits of the fluorescent nanoparticles toward L‐Asp and L‐Glu were calculated to be 2.09×10−7 M and 4.03×10−7 M, respectively. This work provide an efficiency way for highly sensitive detection of L‐Asp and L‐Glu in water. [ABSTRACT FROM AUTHOR]

The detection of volatile aliphatic aldehydes is of significance because of their chemical toxicity, physical volatility and widespread applications in chemical industrial processes. In this work, the direct detection of aliphatic aldehydes is tackled using a pillar[5]arene‐based fluorescent supramolecular polymer with vaporchromic behavior. Thin films with strong orange‐yellow fluorescence are prepared by coating the linear supramolecular polymer on glass sheets. When the thin films are exposed to aliphatic aldehydes with different carbon chain lengths, they can selectively sensing n‐butyraldehyde (C4) and caprylicaldehyde (C8), accompanied by fluorescence quenching, indicating that the supramolecular polymer is a highly selective vapochromic response material for aliphatic aldehydes with long alkyl chains. [ABSTRACT FROM AUTHOR]

The stress‐dominance hypothesis (SDH) predicts that environmental filtering will dominate in harsh habitats, while limiting similarity is more important in favourable environments. Here, we test the generality of the SDH to disentangle the relative importance of these two ecological processes along a sand desertification gradient. Data were collected from randomly selected locations in a desert steppe community in Northwest China. In this region, intense habitat fragmentation has resulted in a series of original soil habitat patches called soil islands. These soil islands typically contain Sierozem soils historically subjected to low (L), medium (M), and high (H) levels of sand desertification. Along this sand desertification gradient, soil properties and leaf traits (LDMC, leaf dry matter content; SLA, specific leaf area; LC, leaf carbon concentration; LP, leaf phosphorus concentration; and LN, leaf nitrogen concentration) were measured. We then tested for trait and phylogenetic convergence or divergence using a null model approach. Along the sand desertification gradient, trait convergence trend decreased, while trait divergence trend increased. Similarly, the phylogenetic convergence trends decreased. Traits displaying convergence included LDMC, SLA, and LCC, while LP and LN displayed divergence. The strength of LDMC convergence was negatively correlated with community weighted mean trait values (CWM) for LDMC. In contrast, the strength of LN divergence was positively correlated with CWM for LN. Our results pertaining to LDMC and LN support the SDH. Along the sand desertification gradient, the strength of environmental filtering gradually decreased, while the intensity of limiting similarity gradually increased. [ABSTRACT FROM AUTHOR]

Introduction: In this study we investigated whether burst-modulated wide-pulse neuromuscular electrical stimulation (NMES) can improve the H-reflex and activation efficiency of sensory fibers.Methods: NMES-induced electromyography (EMG) was recorded from hindpaw plantar muscles in 11 anesthetized rats. A burst-modulated wide pulse (mWP) with three carrier frequencies (2 kHz, 5 kHz, and 10 kHz) and a continuous wide-pulse (WP) were delivered to the tibial nerve of each rat. The evoked Hoffman (H)-reflexes were measured to evaluate nerve activation efficiency using the H-reflex recruitment curve (HRC).Results: Relative to WP simulation, mWP stimulation required less electrical charge to excite sensory fibers and improved the H-reflex recruitment. Greater electrical charge and smaller recruitment gains were obtained with increased carrier frequency of mWP.Discussion: mWP NMES can improve stimulation efficiency and improve recruitment of sensory fibers on tibial nerve stimulation, which may help to optimize NMES stimulus parameters. [ABSTRACT FROM AUTHOR]

A novel supramolecular polymer metallogel (QP5‐AlG) has been constructed by cross‐linking of bis‐8‐hydroxyquinoline functionalized pillar[5]arene with Al3+. The metallogel QP5‐AlG shows light blue aggregation induced emission (AIE) in DMSO/H2O binary solution. Interestingly, the QP5‐AlG shown multiple external stimuli‐responsive behaviors such as temperature, guest compounds, acid, base and so on. The QP5‐AlG can be used as a fluorescent material for detection of Fe3+, F‐, trifluoroacetic acid (TFA) and triethylamine (TEA) by different fluorescence states ("on" or "off"). The (limits of lowest detection) LOQs of the QP5‐AlG for Fe3+, F‐, TFA and TEA are in the range of 4.39 × 10‐9‐1.82 × 10‐7 M. More interestingly, a QP5‐AlG‐based rewritable and erasable fluorescent platform was demonstrated, which offers a potential testbed for performing "write‐erase‐write" cycles multiple times. This study provides insight into the development of novel multifunctional supramolecular materials. [ABSTRACT FROM AUTHOR]

A novel approach for in situ generation of AgI quantum dots by the confinement of a pillar[5]arene‐based supramolecular polymer network has been successfully developed. The supramolecular polymer network (SPN‐QP) was constructed by using a bis‐8‐hydroxyquinoline‐modified pillar[5]arene derivative as a host (H‐QP) and a bis‐pyridinium‐modified decane as guest (G‐PD). The SPN‐QP shows ultrasensitive response for Ag+. The limit of detection is about 7.44×10−9 M..Interestingly, when I− was added to the SPN‐QP+Ag+ system, an unexpected strong warm‐white fluorescence emission was observed. After carefu investigation, we found that the strong warm‐white fluorescence emission could be attributed to the in situ formation of AgI quantum dots under the confinement of the supramolecular polymer network (SPN‐QP). Based on this approach, ultrasensitive detection of I− was realized. The limit of detection for I− is 4.40×10−9 M. This study provides a new way for the preparation of quantum dots under the confinement of supramolecular polymer network as well as ultrasensitive detection of ions by in situ formation of quantum dots. [ABSTRACT FROM AUTHOR]

A material that can simultaneously detect and remove toxic heavy metal Hg2+ ions are still needed in urgent. Herein, we report that an efficient, simple and water‐soluble phenazine hydrochloride (DAPH) chemosensor for colorimetric and fluorogenic detection of Hg2+ in pure water. The fluorescent and UV‐vis detection limits for Hg2+ are low. Meanwhile, the chemosensor is able to effectively remove Hg2+ in pure water through inductively coupled plasma (ICP) analysis. A series of experimental results showed that the chemosensor successfully used to real‐time detect and remove toxic heavy metal Hg2+ ions from water via a simple deprotonation and destroyed phenazine‐based hydrochloride π−π stacking interactions. In addition, the fabricated silica gel plates are also demonstrated excellent selectivity towards Hg2+ ion without interfering. [ABSTRACT FROM AUTHOR]

Nowadays, reducing the fire hazard and improving the mechanical strength of rigid polyurethane foams (RPUFs) at the same time are important research direction in the fields of safety materials. Expandable graphite (EG) is an effective flame retardant for RPUF, but would destroy the compatibility of the matrix. In this article, EG is capsuled by melamine cyanurate (MCA) and then microencapsulated expandable graphite (MCEG) is obtained, which is added into RPUF. The mechanical properties of composites were evaluated by compressive strength test, torsion strength test and shear stress test. The fire characteristics including smoke and heat production of RPUF composites were studied using cone calorimeter test. And the thermal decomposition and flammable properties were further evaluated using thermogravimetric analysis and limiting oxygen index. The results show that the mechanical properties of RPUF containing MCEG are similar with RPUF and better than RPUF containing EG. Furthermore, MCA cover would impede expanding of EG, which weakens the protective and insulation effects of expanding layer. Therefore, the composites containing MCEG decompose faster and produce more smoke than the composites containing EG. However, MCA and EG have the synergistic enhancing effect on the flame retardant property of composite. POLYM. COMPOS., 40:E1006–E1014, 2019. © 2018 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

ABSTRACT: The original flax fibers (FF) and the modified FFs were subjected to the treatment with the flame retardant, were used to improve the performance of rigid polyurethane foams (RPUF). The mechanical properties of composites were evaluated by compressive strength test, torsion strength test, and shear stress test. The fire characteristics (smoke and heat production) were studied using cone calorimeter. And the thermal decomposition and flammable properties were further evaluated using thermogravimetric analysis and limiting oxygen index. The results showed that the FF could improve the mechanical properties of RPUF and had a good prospect in reducing the fire hazard for RPUF. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46436. [ABSTRACT FROM AUTHOR]

One main source of cyanide (CN−) exposure for mammals is through the plant consumption; thus, the sensitive and selective cyanide detection in plant tissue is a significant and urgent work. Here, a simple sensor N′‐(2,4‐dihydroxybenzylidene)naphtha[2,1‐b]furan‐2‐carbohydrazide (Q1‐3) was designed and synthesized for selective and sensitive dual‐channel detection of cyanide in aqueous medium (DMSO/H2O, 1:9, v/v). Acylhydrazone and phenolic hydroxyl groups on Q1‐3 are the recognition sites, and naphthofuran group is the signal report group. The intramolecular charge transfer between the benzene group and naphthofuran group was impeded because of the electron‐withdrawing groups (hydroxyl) on sensor Q1‐3. Interestingly, the sensor Q1‐3 exhibited an intramolecular charge transfer absorption band at 400 nm and emission band at 500 nm, respectively, directly realizing an “OFF–ON” response after the deprotonation process induced by cyanide anions in aqueous medium (DMSO/H2O, 1:9, v/v). Notably, this sensor was successfully applied to detect cyanide anions in food samples, which proves a very simple and selective platform for on‐site monitoring of cyanide in agriculture samples. In addition, the test strips and silica gel plates based on Q1‐3 were also fabricated, which could act as test kits and silica gel plates for convenient and efficient detection of cyanide anions. [ABSTRACT FROM AUTHOR]

The Paleoproterozoic Dhala structure with an estimated diameter of ~11 km is a confirmed complex impact structure located in the central Indian state of Madhya Pradesh in predominantly granitic basement (2.65 Ga), in the northwestern part of the Archean Bundelkhand craton. The target lithology is granitic in composition but includes a variety of meta-supracrustal rock types. The impactites and target rocks are overlain by ~1.7 Ga sediments of the Dhala Group and the Vindhyan Supergroup. The area was cored in more than 70 locations and the subsurface lithology shows pseudotachylitic breccia, impact melt breccia, suevite, lithic breccias, and postimpact sediments. Despite extensive erosion, the Dhala structure is well preserved and displays nearly all the diagnostic microscopic shock metamorphic features. This study is aimed at identifying the presence of an impactor component in impact melt rock by analyzing the siderophile element concentrations and rhenium-osmium isotopic compositions of four samples of impactites (three melt breccias and one lithic breccia) and two samples of target rock (a biotite granite and a mafic intrusive rock). The impact melt breccias are of granitic composition. In some samples, the siderophile elements and HREE enrichment observed are comparable to the target rock abundances. The Cr versus Ir concentrations indicate the probable admixture of approximately 0.3 wt.% of an extraterrestrial component to the impact melt breccia. The Re and Os abundances and the 187Os/188Os ratio of 0.133 of one melt breccia specimen confirm the presence of an extraterrestrial component, although the impactor type characterization still remains inconclusive. [ABSTRACT FROM AUTHOR]

Objective Severe aplastic anemia ( SAA) is a rare immune-regulated disease characterized by severe pancytopenia and bone marrow failure, caused by destruction of hematopoietic cells by the activated T lymphocytes. Linker for activation of T cells ( LAT), a transmembrane adaptor protein, plays a key role in T-cell and mast cell functions. However, it remains unclear how LAT may change in patients with SAA. This study aims at understanding the role of lymphocyte LAT in SAA. Methods The expression of LAT, related signaling molecules, and T-cell effector molecules was determined by flow cytometry. LAT m RNA was evaluated by quantitative real-time PCR. Cytokine production by cultured T cells was determined by ELISA. Results Patients with SAA had an increased levels of LAT and both total phosphorylated LAT and of the related molecule ( ZAP-70) in circulating T cells compared with normal controls. In patients with SAA, the expression of LAT was positively associated with the expression of perforin and granzyme B in CD8+ T cells. Inhibition of LAT expression in T cells from patients with SAA decreased the activation of the CD4+ and CD8+ T-cell subsets. Overexpression of LAT in T cells from normal controls increased the activation of CD4+ and CD8+ T-cell subsets with increased apoptosis of K562 cells in coculture. Conclusions Our findings demonstrate that dysregulation of LAT expression and activation may contribute to over-function of T cells, imbalance of Th1/Th2 subsets and thus lead to hematopoiesis failure in SAA. Immunosuppressive therapy dramatically reduced the expression of LAT making it an attractive therapeutic target in SAA. [ABSTRACT FROM AUTHOR]

A facile and simple catalyst-free protocol has been developed for the condensation of 1,2-diketones with aromatic 1,2-diamines in polyethylene glycol (PEG), providing quinoxaline derivatives in good yields. The important features of the methodology are broad substrates scope, simple workup, catalyst free, environmentally benign, and no requirement for metal catalysts. It is noteworthy that the cyclization reaction of 1,2-diketones with aliphatic 1,2-diamines is also conducted smoothly to afford pyrazines in good yields under the standard conditions. In addition, PEG could be recovered easily and was reused without evident loss in activity [ABSTRACT FROM AUTHOR]

Spent coal-based activated carbon from the silicon industry has been used as raw material for the regeneration of activated carbon, with carbon dioxide as the regenerating agent. The regeneration process was optimised using response surface methodology and the optimum regeneration conditions were: regeneration temperature 985 °C; regeneration time 120 min; and carbon dioxide flow rate of 600 ml/min. The iodine number and yield of the activated carbon obtained under the optimum regeneration conditions were 1071 mg/g and 67%, with a Brunauer-Emmet-Teller surface area of 1270 m2/g and pore volume of 0.91 cm3/g. The regenerated carbon was tested for the removal of Methylene Blue dyes. The maximum adsorption capacity was found to be 395 mg/g and the equilibrium data fitted to the Langmuir isotherm model. The kinetic data indicated that the best fit corresponds to the pseudo-second-order kinetic model. [ABSTRACT FROM AUTHOR]

J. Neurochem. (2011) 119, 644-653. Abstract Excessive astrogliosis is a major impediment to axonal regeneration in CNS disorders. Overcoming this inhibitory barrier of reactive astrocytes might be crucial for CNS repair. Up-regulation and activation of epidermal growth factor receptor (EGFR) has been shown to trigger quiescent astrocytes into reactive astrocytes in response to several neural injuries. In this study, we investigated the effects of EGFR blockade in cultured astrocytes exposure to oxygen-glucose deprivation/reoxygenation (OGD/R) and in the rat middle cerebral artery occlusion (MCAO) model. Astrocytes in primary culture were used for OGD/R model and adult male Sprague-Dawley rats were used for MCAO model. Cell cycle progression of astrocytes in vitro was studied by flow cytometric analysis. Expression of phosphorylated epidermal growth factor receptor (p-EGFR), glial fibrillary acidic protein (GFAP), and cell proliferation-related molecules in vitro and in vivo were evaluated by immunostaining and western blot analysis. Neuronal apoptosis after MCAO was determined by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) method. Neurologic scores and infarct volumes post-ischemia were assessed in the rat MCAO model. Astrocytes became activated in the cultured astrocytes exposure to OGD/R and in the rat brain after MCAO, accompanied with phosphorylation of EGFR. EGFR blockade significantly decreased expression of p-EGFR, inhibited cell cycle progression of astrocytes, and reduced reactive astrogliosis in vitro and in vivo. EGFR inhibition also reduced infarct volumes and improved neurologic scores of rats after MCAO. Our findings indicated that blocking EGFR pathway might attenuate reactive astrogliosis through inhibiting cell cycle progression and protect against ischemic brain injury in rats. [ABSTRACT FROM AUTHOR]

A middle-aged woman presented at our facility and was diagnosed after surgery with lung papillary adenocarcinoma. Seven years earlier, she had suffered from autoimmune hemolytic anemia ( AIHA), which was refractory. Following lung surgery, the AIHA was cured. [ABSTRACT FROM AUTHOR]

Recycled poly(ethylene terephthalate) (PET), subjected to the treatment with the flame retardant first, was used to reinforce the rigid polyurethane foams (RPUFs). Different loadings of PET fibers (3–12 wt %) of different lengths (5, 10, 15, and 20 mm) were added into RPUF. The mechanical properties of composites were studied by compressive strength test and shear stress test. The flame‐retardant properties were evaluated by cone calorimeter and limited oxygen index test. The results showed that the proper addition of PET fibers could improve the mechanical and flame‐retardant properties of the material. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47758. Compressive strength of RPUF containing various fibers. [ABSTRACT FROM AUTHOR]

Compared to previously reported methodologies, the present, environmentally benign method features a simple workup, a wide range of substance scope and no need of any catalysts. [ABSTRACT FROM AUTHOR]

Mannich reaction of N-methyl-N′-nitroguanidine (I) in the presence of alkaline catalysts provides access to the title oxadiazine (III) and triazine derivative (IV). [ABSTRACT FROM AUTHOR]

The title compound C18H14N2O2, forms centrosymmetric dimers via inter­molecular O—H⋯N hydrogen bonds, with an O⋯N distance of 2.688 (3)Å and an O—H⋯N angle of 163°. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The construction of multi‐responsive supramolecular systems for drug delivery is a challenging task. In this work, a Pd2L4 metallacage 1·([BF4]−)4 with four pyrene units was first designed and synthesized through coordination‐driven self‐assembly. After the introduction of γ‐CD, a supramolecular amphiphile 1–γ‐CD was successfully constructed based on the host–guest molecular recognition between γ‐CD and the pyrene unit of 1·([BF4]−)4, which further self‐assembled into dual‐responsive supramolecular vesicles in aqueous solution. DOX·HCl was used as a model molecule to study the drug encapsulation and release behavior of the supramolecular vesicles. By adjusting the pH of the solution to acidic condition or adding a certain amount of α‐amylase, the vesicle structure was destroyed to achieve rapid and effective release of the drug molecules. This study provides an example for the rational design of efficient dual‐responsive supramolecular nanocarriers, which have potential application value in the field of controlled drug delivery. [ABSTRACT FROM AUTHOR]