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A highly stereoselective synthesis of a cyclic dinucleotide (CDN) STING agonist containing two chiral thiophosphoramidate linkages is described. These rare, yet key functional groups were, for the first time, installed efficiently and with high diastereoselectivity using a specially designed P(V) reagent. By utilizing this strategy, the CDN was prepared in greater than sixteen-fold higher yield than the prior P(III) approach, with fewer hazardous reagents and chromatographic purifications.

Treatment of congenital pseudarthrosis of the tibia (CPT) still is full of challenges in pediatric orthopedist. Serum-derived exosomes (SDEs) have been proven to be participated in bone remodeling. However, the molecular changes in SDEs of CPT children and their pathologies have not been elucidated. In this study, SDEs were isolated and purified from CPT patients (CPT-SDEs) associated with neurofibromatosis type 1 (NF1) and normal children (Norm-SDEs). Then we obtained the proteomics profile of SDEs by combining liquid chromatography-tandem mass spectrometry (LC-MS/MS) and tandem mass tag label-based quantitation. In vitro, the efficacy of SDEs on osteoblastic differentiation of MC3T3-E1 cells and osteoclastogenesis ability of RAW264.7 cells were evaluated by quantitative real-time PCR (qRT-PCR) and cytochemical staining. In vivo, we used micro-CT to assess cortical bone mass and trabecular microstructures to reflect the influence of SDEs on bone remodeling after injection into the tail vein of rats. Based on proteomics analysis, 410 differentially expressed proteins, including 289 downregulated proteins and 121 upregulated proteins, were identified in the CPT-SDEs. These proteins have multiple biological functions associated with cellular metabolic processes, catalytic activity, and protein binding, which are important for cell differentiation and proliferation. In vitro, CPT-SDEs decreased the osteogenic differentiation of MC3T3-E1 cells and promoted the osteoclastogenesis of RAW264.7 cells. Injection of CPT-SDEs into the tail vein for two months resulted in bone loss in rats, as indicated by the decrease in trabecular and cortical bone mass. Our findings demonstrated the differences in proteins in SDEs between normal and CPT children with NF1. These differentially expressed proteins in CPT-SDEs contributed to deteriorating trabecular bone microstructures by inhibiting bone formation and stimulating bone resorption.

Breast cancer (BC), a common malignancy, is intractable at present. Cuprous oxide nanoparticles (Conps) are new nanoparticles crucial in inhibiting tumor progression according to early studies, but their role in BC remains unclear. Field emission-scanning electron microscopy (FESEM) and field emission–transmission electron microscopy (FETEM) were used for the morphological observation of Conps, and energy-dispersive X-ray spectroscopy was used for their elemental composition analysis. Multipoint nitrogen adsorption was used to determine the Brunauer–Emmet–Teller of Conps, and their mean hydrodynamic size and zeta potential in water and intact cell medium were determined by dynamic light scattering (DLS). 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, Cell Counting Kit-8, Transwell assay, and flow cytometry were used to determine the effects of Conps on the biological function of BC cells. Western blotting was used to determine the changes in apoptosis-related proteins. Using FESEM and FETEM based on DLS and zeta potential determination, Conps was successfully constructed. Conps significantly lowered the viability of BC cells in a dose-dependent manner, significantly inhibited cell proliferation, invasion, and migration activities, and induced cell apoptosis. Western blotting demonstrated that Conps up-regulated Bax and caspase-3 proteins and down-regulated Bcl-2 protein. The results suggest that Conps can suppress the proliferation, invasion, and migration of BC cells and accelerate their apoptosis. This is a new potential strategy for the clinical treatment of BC.

Oxidative transformations of HMF are key routes toward a wide variety of chemicals and biofuels through an environmental friendly process. Co3O4 NPs decorated Mn-Co-O solid solution, donated as Co3O4/MnXCo, was prepared by co-precipitation method and used as non-precious metal catalyst for base-free oxidation of HMF to FDCA in the presence of O2 and water. Comprehensive characterizations such as XRD, H2-TPR, O2-TPD, XPS, NH3/CO2-TPD and TEM were used to study materials properties especially the oxygen mobility and acidity-basicity. The effect of Mn/Co molar ratio in catalyst and the reaction conditions were investigated and optimized. In addition, the kinetics of the reaction was monitored to reveal the reaction route and rate-determining step. The variation of Mn/Co molar ratio was found to affect not only HMF conversion but also distribution of products. When the Mn/Co ratio was of 0.2, the Co3O4/Mn0.2Co catalyst showed the optimal catalytic performance (i.e., >99% yield of FDCA obtained under 1 bar O2 at 140 °C after 24 h) due to the highest content of both Lewis and Bronsted acid sites on the surface, leading to the strongest ability of HMF adsorption and COOH group formation, as well as the enhanced oxygen mobility. This catalyst was shown stable after a minor deactivation (≤8%) during six recycling uses and its activity can be entirely regenerated by calcination in air.

Bone fracture is one of the most common injuries. Despite the high regenerative capacity of bones, failure of healing still occurs to near 10% of the patients. Herein, we aim to investigate the modulatory role of neurofibromatosis type I gene (NF1) to osteogenic differentiation of bone marrow–derived mesenchymal stem cells (BMSCs) and new bone formation after fracture in a rat model. We studied the NF1 gene expression in normal and non‐union bone fracture models. Then, we evaluated how NF1 overexpression modulated osteogenic differentiation of BMSCs, autophagy activity, mTORC1 signalling and osteoclastic bone resorption by qRT‐PCR, Western blot and immunostaining assays. Finally, we injected lentivirus‐NF1 (Lv‐NF1) to rat non‐union bone fracture model and analysed the bone formation process. The NF1 gene expression was significantly down‐regulated in non‐union bone fracture group, indicating NF1 is critical in bone healing process. In the NF1 overexpressing BMSCs, autophagy activity and osteogenic differentiation were significantly enhanced. Meanwhile, the NF1 overexpression inhibited mTORC1 signalling and osteoclastic bone resorption. In rat non‐union bone fracture model, the NF1 overexpression significantly promoted bone formation during fracture healing. In summary, we proved the NF1 gene is critical in non‐union bone healing, and NF1 overexpression promoted new bone formation after fracture by enhancing autophagy and inhibiting mTORC1 signalling. Our results may provide a novel therapeutic clue of promoting bone fracture healing.

Objective. Arsenic trioxide (Pishuang, Pishi, arsenolite, As2O3, and CAS 1327-53-3), a naturally occurring and toxic mineral as a drug for more than 2000 years in China, has been found to have a valuable function in hepatocellular carcinoma (HCC) in recent years. However, its exact mechanism remains to be elucidated. Therefore, this study was intended to explore the potential anti-HCC mechanism of arsenic trioxide through network pharmacology. Methods. The potential targets of arsenic trioxide were collected from PubChem and TargetNet. HCC targets were obtained from the GeneCards database. Then, a protein-protein interaction (PPI) network of arsenic trioxide and HCC common targets was established using STRING. GO and KEGG pathway enrichment analyses were performed by the Database for Annotation, Visualization, and Integrated Discovery (DAVID). Finally, an arsenic trioxide-target-pathway-HCC network was built by Cytoscape 3.2.1, and network topological analysis was carried out to screen the key candidate targets. Results. A total of 346 corresponding targets of arsenic trioxide and 521 HCC-related targets were collected. After target mapping, a total of 52 common targets were obtained. GO analysis showed that the biological process was mainly involved in the negative regulation of cellular senescence, response to tumor necrosis factor, and cellular response to hypoxia. Molecular functions included NF-kappa B binding, enzyme binding, p53 binding, and transcription factor binding. Cellular components mainly were replication fork, ESC/E(Z) complex, RNA polymerase II transcription factor complex, and organelle membrane. KEGG pathways were mainly enriched in the PI3K-Akt signaling pathway, VEGF signaling pathway, p53 signaling pathway, HIF-1 signaling pathway, TNF signaling pathway, AMPK signaling pathway, NF-kappa B signaling pathway, FoxO signaling pathway, ErbB signaling pathway, and MAPK signaling pathway. In the arsenic trioxide-target-pathway-HCC network, targets such as AKT1, RAF1, RELA, TP53, and PTEN had a higher degree. Conclusions. Our study showed that key targets of arsenic trioxide were mainly involved in multiple biological processes and pathways. It provided a theoretical basis for the screening of drug targets.

Predicting gas permeabilities of polymers a priori is a long-standing challenge within the membrane research community that has important applications for membrane process design and ultimately widespread adoption of membrane technology. From early attempts based on free volume and cohesive energy to more recent group contribution methods, the ability to predict membrane permeability has improved in terms of accuracy. However, these models usually stay “within the paper”, i.e. limited model details are provided to the wider community such that adoption of these predictive platforms is limited. In this work, we combined an advanced polymer chemical structure fingerprinting method with a large experimental database of gas permeabilities to provide unprecedented prediction precision over a large range of polymer classes. No prior knowledge of the polymer is needed for the prediction other than the repeating unit chemical formula. In addition, we have incorporated this model into the existing Polymer Genome project to make it open to the membrane research community.

Two-dimensional (2D) layered zeolites are new forms of 3D zeolite frameworks. They can be pillared to form more open porous structures with increased access for reactants that are too big for the micropores of zeolites. The current pillaring procedure, however, requires intercalation of pillaring precursors by dispersing 2D zeolite in an alkoxide liquid and hydrolizing entrapped alkoxide to form inorganic oxide pillars in an aqueous alkaline solution. Both steps use excess solvents, generate significant waste, and require multiple synthesis and separation steps. Here we report a vapor-phase pillarization (VPP) process to produce pillared zeolites from 2D layered zeolite structures. The VPP process has ∼100% efficiency of alkoxide usage in the intercalation step, requires less (and, in some cases, zero) water addition in the hydrolysis step, does not require separation for product recovery, and generates no liquid waste. Furthermore, synthesis of pillared zeolites via the VPP process can be accomplished within a single apparatus with one-time operation. The pillared zeolite prepared by the VPP method preserved the zeolitic layered structure as well as acidity and showed enhancement in catalytic alkylation of mesitylene with benzyl alcohol compared to 2D layered zeolite without pillarization treatment.

Podocytes are essential components of the glomerular basement membrane. Epithelial-mesenchymal-transition (EMT) in podocytes results in proteinuria. Fibroblast growth factor 1 (FGF1) protects renal function against diabetic nephropathy (DN). In the present study, we showed that treatment with an FGF1 variant with decreased mitogenic potency (FGF1ΔHBS) inhibited podocyte EMT, depletion, renal fibrosis, and preserved renal function in two nephropathy models. Mechanistic studies revealed that the inhibitory effects of FGF1ΔHBS podocyte EMT were mediated by decreased expression of transforming growth factor β1 via upregulation of PPARγ. FGF1ΔHBS enhanced the interaction between PPARγ and SMAD3 and suppressed SMAD3 nuclei translocation. We found that the anti-EMT activities of FGF1ΔHBS were independent of glucose-lowering effects. These findings expand the potential uses of FGF1ΔHBS in the treatment of diseases associated with EMT.

The powertrain system is critical to the reliability of a battery electric vehicle (BEV). However, the BEV powertrain is a complex system, it includes the motor, motor controller, power distribution unit, battery system, etc. The failure of any of these components may result in the failure of the entire powertrain system and eventually cause serious traffic accidents on the road. However, how much does each component affect the reliability of the entire system, and which components are the most vulnerable in the entire system? These questions are still unanswered today. To develop a reliability design for a BEV powertrain system, it is essential to conduct detailed research by investigating the most vulnerable component parts of the entire powertrain. In the present study, a fault-tree model of the entire powertrain and its subsystems was developed. Based on this model, the failure rates of all components were calculated first. Then, trends in the reliability indices for the entire powertrain and its components were estimated against BEV service life. From the estimation results, we learned that with increased service time, the reliability of the entire powertrain system is indeed much lower than that of its individual subsystems. Moreover, through comparative research, we found that the battery module is the most unreliable component not only of the battery system, but the entire powertrain system. Additionally, it was interesting to find that the reliability of the motor components was higher than that of other subsystem components, but that the reliability indices for the entire motor were not the highest among all the powertrain subsystems studied in this paper. We believe the findings of the present study will be of great significance to an improved understanding of the reliability design and maintenance of BEVs.

As a classically known mitogen, fibroblast growth factor 1 (FGF1) has been found to exert other pleiotropic functions such as metabolic regulation and myocardial protection. Here, we show that serum levels of FGF1 were decreased and positively correlated with fraction shortening in diabetic cardiomyopathy (DCM) patients, indicating that FGF1 is a potential therapeutic target for DCM. We found that treatment with a FGF1 variant (FGF1∆HBS) with reduced proliferative potency prevented diabetes-induced cardiac injury and remodeling and restored cardiac function. RNA-Seq results obtained from the cardiac tissues of db/db mice showed significant increase in the expression levels of anti-oxidative genes and decrease of Nur77 by FGF1∆HBS treatment. Both in vivo and in vitro studies indicate that FGF1∆HBS exerted these beneficial effects by markedly reducing mitochondrial fragmentation, reactive oxygen species (ROS) generation and cytochrome c leakage and enhancing mitochondrial respiration rate and β-oxidation in a 5’ AMP-activated protein kinase (AMPK)/Nur77-dependent manner, all of which were not observed in the AMPK null mice. The favorable metabolic activity and reduced proliferative properties of FGF1∆HBS testify to its promising potential for use in the treatment of DCM and other metabolic disorders.

Chirality control plays a critical role in developing stereoisomeric drugs. Due to the complexity and lack of predictability in chiral separations, column screening remains the gold standard to initiate chiral method development for active pharmaceutical ingredients (APIs) and synthetic intermediates. Chiral reversed-phase (RP) liquid chromatography (LC) has gained favor over other modes due to its versatility and compatibility in analyzing a wide range of chiral compounds in various matrices. Herein, we established a tier-based chiral RPLC screen strategy by constructing and analyzing a database of 101 chiral screens with a total of 3,401 entries (unique LC runs) for proprietary APIs or intermediates at Bristol Myers Squibb. Up to 17 polysaccharide-based chiral stationary phases (CSPs) and four mobile phases (MPs) have been screened with gradient elution. A selection of ten CSPs with two MPs was found sufficient to achieve successful separation for 82% of the total screens. Two RPLC screen tiers (Tier 1: AZ, OD, ID, and IG) and (Tier 2: AY, OJ, OZ, IA, IC, and IH) were proposed along with two MPs (acidic and neutral) to target ~70% hit rate for Tier 1, and ~80% for the combined set. We also implemented a user-friendly workflow to enable walk-up chiral RPLC screening with automated reports and system suitability tests.

Direct CO2 capture from atmospheric air is gaining increased attention as one of the most scalable negative carbon approaches available to tackle climate change if coupled with the sequestration of...

The use of nanoporous zeolitic imidazolate frameworks (ZIFs) in separation processes is attractive, but the presence of acid gases such as SOx or NOx in process streams can have detrimental effects. While we have recently developed a mechanistic picture of SOx–ZIF interactions, here we describe the remarkably different effects of NO2 on ZIFs. ZIFs with a representative range of SOx stabilities are all unstable—as defined by loss of crystallinity and porosity—in dry and humid NO2, whereas most ZIFs are stable in dry SOx and some even in humid SOx. A detailed mechanism is developed based on Fourier transform infrared spectroscopy and density functional theory calculations. H-abstraction by free radical NO2 and subsequent acidic species formation are the major degradation pathways, while adsorbed HNO3 formation in humid conditions is an additional pathway in hydrophilic ZIFs. These findings strongly suggest that new strategies to stabilize ZIFs/metal–organic frameworks toward NO2 attack are required.

Here, we describe the formation of zeolite LiX fiber sorbents and postfabrication activation at temperatures of 350–400 °C for use in air separations. Two polymers were considered as the support matrices for the LiX zeolites: Torlon (polyamide-imide) and Matrimid (polyimide). Torlon-based fiber sorbents exhibit approximately 4% mass loss during the high-temperature (370 °C) activation required for zeolites, which is close to the glass transition temperature of these polymers. This mass loss is accompanied by the formation of pyrolytic side products that ultimately resulted in contamination of the LiX crystals and a 73% reduction in N2 sorption capacity at ambient temperatures. In contrast, Matrimid was found to be suitable for fiber sorbent synthesis with only 10–15% reduction in N2 sorption capacity observed upon the thermal activation. A LiX loading of 73% in monolithic fibers (i.e., no bore) by weight was achievable. Experimental breakthrough tests at 25 °C were conducted on an activated fiber module c...

Parent and amine-functionalized analogues of metal–organic frameworks (MOFs), UiO-66(Zr), MIL-125(Ti), and MIL-101(Cr), were evaluated for their hydrogen sulfide (H2S) adsorption efficacy and post-exposure acid gas stability. Adsorption experiments were conducted through fixed-bed breakthrough studies utilizing multicomponent 1% H2S/99% CH4 and 1% H2S/10% CO2/89% CH4 natural gas simulant mixtures. Instability of MIL-101(Cr) materials after H2S exposure was discovered through powder X-ray diffraction and porosity measurements following adsorbent pelletization, whereas other materials retained their characteristic properties. Linker-based amine functionalities increased H2S breakthrough times and saturation capacities from their parent MOF analogues. Competitive CO2 adsorption effects were mitigated in mesoporous MIL-101(Cr) and MIL-101–NH2(Cr), in comparison to microporous UiO-66(Zr) and MIL-125(Ti) frameworks. This result suggests that the installation of H2S binding sites in large-pore MOFs could potenti...

The hydrogen sulfide composition in biogas ranges from 0 to 5% depending on the feed source to the biogas digester. To meet renewable natural gas specifications of 0–4 ppm of H2S content, technologies that remove H2S from raw biogas feeds are needed. This contribution assesses three adsorbents with similar textural and physical properties but with different amines grafted to the surface. Specifically, materials containing primary, secondary, and tertiary amines at the end of a propyl surface linker grafted on a silica support are explored. H2S adsorption isotherms and cyclic studies are presented for these materials, and it is shown that secondary amines have the best amine efficiency while tertiary amines are the most stable for H2S capture, of the materials studied. The results suggest the consideration of secondary and tertiary amines for the design of amine adsorbents suitable for H2S removal in dilute gas streams over multiple cycles.

The interaction between hydrogen sulfide and ZIF-8 was studied via structural characterizations and guest molecule diffusion measurements. It was found that hydrogen sulfide reacts with the ZIF-8 external particle surface to form a surface barrier that excludes the uptake of larger molecules (ethanol) and slows down the uptake of smaller molecules (carbon dioxide). Nonetheless, bulk transport properties were unaltered, as supported by pulsed field gradient nuclear magnetic resonance studies. Dispersion-corrected density functional theory calculations revealed that H2S is consumed by reactions occurring at the ZIF external surface. These reactions result in water and defect formation, both of which were found to be exothermic and independent of both crystallographic facets ({001} and {110}) and surface termination. We concluded that these surface reactions lead to structural and chemical changes to the ZIF-8 external surface that generate surface barriers to molecular transport.

Wild and cultivated Licorice ( Glycyrrhiza uralensis FISCH.) are the main source of licorice. In recent years, wild Glycyrrhiza plants have been seriously damaged and this has reduced the population. The cultivation of Licorice has been the best way to solve the problem of its shortage. The contents of glycyrrhizic acid greatly differs in licorices cultivated at different region of China. However, the contents of glycyrrhizic acid in cultivated licorice in china is lower than that of wild licorice. To produce the high quality cultivated licorices, researchers studied the factors affecting the glycyrrhizic acid produced in licorice. It was found that manganese (Mn) application improved the medicinal material yieldand quality especially the contents of the glycyrrhizic acid. In this paper, we investigated the effects of Mn on the accumulation of glycyrrhizic acid in medicinal materials based on the material ingredients distribution and also explored the mechanism. The influence of Mn on the relative contents of glycyrrhizic acid were significant except for day 30 while the influence is significant to the absolute contents all the time. The relative contents of glycyrrhizic acid increased while the contents of crude protein, crude fiber and total material ingredients decreased. The absolute contents of glycyrrhizic acid rose when crude protein contents increased. This implies that the contents of glycyrrhizic acid are in a close relationship with material ingredients. Mn application of appropriate concentration could stimulate the formation of primary metabolites, and then promote the secondary metabolism of G. uralensis which could lead to the formation and accumulation of glycyrrhizic acid in G. uralensis .

Porous organic cages (POCs) are emerging porous materials that exhibit intriguing properties in the areas of self-assembly, host–guest interaction, and solution processability. In this work, we explore the applicability of POCs as molecular porous supports for polymeric amines. We find that primary amines in poly(ethylenimine) (PEI) can undergo metathesis with the imine bonds present in POCs, resulting in non-porous products. This problem can be overcome by transforming the primary amines in PEI to tertiary amines via methylation. The methylated PEI (mPEI) forms homogeneous composites with amorphous scrambled porous organic cages (ASPOCs) without undesired reactions or phase separation. The microscopic structure of the composites is studied using molecular dynamics simulations. These composite materials are evaluated as adsorbents for low concentration SO2 (200 ppm) adsorption and show good thermal and cyclic stability.

The synthesis of hierarchical lamellar zeolites with a controlled meso-/microporous morphology and acidity is an expanding area of research interest for a wide range of applications. Here, we report a one-step synthesis of a hierarchical meso-/microporous lamellar MFI–Sn/Al zeolite (i.e., containing both Lewis acidic Sn- and Al-sites and a Bronsted acidic Al–O(H)–Si site) and its catalytic application for the conversion of glucose into 5-(ethoxymethyl)furfural (EMF). The MFI–Sn/Al zeolite was prepared with the assistance of a diquaternary ammonium ([C22H45–N+(CH3)2–C6H12–N+(CH3)2–C6H13]Br2−, C22-6-6) template in a composition of 100SiO2/5C22-6-6/18.5Na2O/xAl2O3/ySnO2/2957H2O (x = 0.5, 1, and 2; y = 1 and 2, respectively). The MFI–Sn/Al zeolites innovatively feature dual meso-/microporosity and dual Lewis and Bronsted acidity, which enabled a three-step reaction cascade for EMF synthesis from glucose in ethanol solvent. The reaction proceeded via the isomerization of glucose to fructose over Lewis acidic Sn sites and the dehydration of fructose to 5-hydroxymethylfurfural (HMF) and then the etherification of HMF and ethanol to EMF over the Bronsted acidic Al–O(H)–Si sites. The co-existence of multiple acidities in a single zeolite catalyst enabled one-pot cascade reactions for carbohydrate upgrading. The dual meso-/microporosity in the MFI–Sn/Al zeolites facilitated mass transport in processing of bulky biomass molecules. The balance of both types of acidity and meso-/microporosity realized an EMF yield as high as 44% from the glucose reactant.

Syntheses of porous organic cages (POCs) represent an important synthetic puzzle in dynamic covalent chemistry-based self-sorting. Improved understanding of the formation mechanisms of POCs can lead to control and rational design of cages with desired functionality. Herein, we explore the formation mechanisms of imine-based POCs using time-resolved electrospray mass spectrometry and electronic structure calculations at the density functional theory and correlated molecular orbital theory levels. We found that the synthesis of the [4 + 6] cycloimine cage CC3-R and the [2 + 3] cycloimine cage CC-pentane both proceed through similar intermediates via a series of consecutive reactions. The proposed reaction mechanisms are supported by electronic structure calculations. On the basis of our observations from both experiments and calculations, we propose a comprehensive method for designing and predicting new POC species. In addition, the observation of stable incomplete cages during CC3-R synthesis inspired us ...

Defect engineering in metal–organic frameworks (MOFs) is an emerging strategy that can be used to control physical or chemical characteristics of MOFs, including adsorption behavior and textural, mechanical, and conductive properties. Understanding the impact of defects on textural properties and chemical stability of MOFs is imperative to the development of MOFs with tunable defect sites. In this work, systematic adsorption measurements were performed with three adsorbate molecules (SO2, benzene, and cyclohexane) to investigate changes in the pore size of defective UiO-66. Compared to the parent UiO-66, the defective UiO-66 shows significant changes in adsorption capacities among the selected adsorbate molecules, demonstrating that pore size is significantly enlarged by the missing cluster defects. BET surface area analysis and DFT calculations were also performed to interrogate the chemical stability of the defective MOFs after exposure to water and acidic environments. This work shows that pore size ca...

The fabrication of porous molecules, such as metal-organic polyhedra (MOPs), porous organic cages (POCs) and others, has given rise to the potential for creating "solid solutions" of molecular fillers and polymers. Such solid solutions circumvent longstanding interface issues associated with mixed matrix membranes (MMMs), and are referred to as molecularly mixed composite membranes (MMCMs) to distinguish them from traditional two-phase MMMs. Early investigations of MMCMs highlight the advantages of solid solutions over MMMs, including dispersion of the filler, anti-plasticization of the polymer network, and removal of deleterious interfacial issues. However, the exact microscopic structure as well as the transport modality in this new class of membrane are not well understood. Moreover, there are clear engineering challenges that need to be addressed for MMCMs to transition into the field. In this Minireview, the authors outline several scientific and technological challenges associated with the aforementioned questions and their suggestions to tackle them.

The synthesis of hierarchical meso-/microporous zeolite materials with spatially controlled morphology, meso-/microporosity, and acidity is an expanding area of research interest for a wide range of applications. Here, we report a one-step dual template synthesis method for integration of 3-dimensional (3D) BEA nanosponge and ultra-thin 2D lamellar MFI into a new type of hierarchical meso-/microporous zeolite composite structures. Specifically, the 2D layered MFI nanosheets were laid over the surface of or interdigitated into the 3D BEA particles in the bulk BEA nanosponge-lamellar MFI (BBLM) zeolite structure, which generated a unique morphology of interconnected micropores and mesopores underneath the ‘skinning’ shell (∼3–10 nm) of MFI nanosheets. The BBLM zeolites have higher mesoporosity than either bare BEA or lamellar MFI zeolites. The micropore size decreases with increasing lamellar MFI component in the composite. The fraction of external acid sites of BBLM zeolite composite, represented by the percentage of active sites accessible to bulky organic base molecules, decreases with increasing MFI component. Additionally, the types of acid sites are diversified in the BBLM composites compared to either bare BEA or lamellar MFI zeolites. The catalysis tests using conversion of benzyl alcohol in mesitylene showed that BBLM zeolites had significant higher activity and durability than single zeolites or their physical mixture. The BBLM zeolite composite provides a good model catalyst with integrated 2D-3D structures and meso-/microporosity for studying a series of important catalytic reactions in hierarchical zeolites. The one-step dual template synthesis method described herein is versatile and facile, which may prove to be a general platform for hierarchical zeolite composite design at the unit-cell scales of zeolites and with potentially broader applicability to other porous materials.

BACKGROUND Piperine has been reported to inhibit proliferation and induce apoptosis in various cancer cells. This study aimed to explore the efficacy and underlying mechanism of piperine in human gastric cancer. MATERIAL AND METHODS MTT assay was performed to examine the effect of piperine (concentrations of 0-300 μM) on the proliferation of human gastric cancer SNU-16 cells and normal human gastric epithelial GES-1 cells. Flow cytometry and Western blot were used to determine cell apoptosis and the expression level of protein (Cyto C, cleaved PARP, cleaved caspase-3, Bax, Bcl-2, Bad, Bcl-xl, PI3K, pPI3K, Akt, and pAkt), respectively. To further investigate the anti-tumor mechanism of piperine in SNU-16 cells, we used a small-molecule Akt activator SC79 in this study. The in vivo mechanism of piperine against gastric cancer was evaluated using a xenograft tumor model. RESULTS The results showed that piperine inhibited proliferation and induced apoptosis of SNU-16 cells. Piperine upregulated the protein expression of Bax, Bad, Cyto C, cleaved PARP, and cleaved caspase-3, but downregulated the protein expression of Bcl-2, Bcl-xl, pPI3k, and pAkt. However, SC79 reversed the function of piperine on the apoptosis-related proteins. An in vivo study revealed that, compared with the control group, the tumor volume of mice treated with piperine was significantly reduced. Piperine enhanced cleaved caspase-3 expression but decreased Ki-67 expression in a dose-dependent manner. Moreover, the nontoxicity effect of piperine was confirmed by H&E staining analysis in kidney and heart tissues of mice. CONCLUSIONS Our findings suggest that piperine inhibits proliferation and induces apoptosis of human gastric cancer cells through inhibition of the PI3K/Akt signaling pathway.

Porous organic cages (POCs) are individual soluble, porous molecules. When fabricated into mixed-matrix membranes (MMMs), the soluble POC molecules have the potential to exhibit intimate molecular-level mixing with the polymer matrix. POCs have only recently been incorporated into mixed matrix membrane materials, but this process has not yet resulted in significant improvements of membrane performance. Now, vertex-functionalized amorphous scrambled porous organic cages (ASPOCs) have been utilized as membrane performance enhancers and the amorphous ASPOC mixtures are observed to distribute throughout the matrix without any indication of particle formation or agglomeration, creating unique, molecularly mixed composite membranes. Overall, the molecularly mixed composite membrane provide significant increases in both membrane permeability and selectivity, offering new avenues for creation of membranes with unique properties in industrially relevant separations.

A comparison of selectivity in catalytic conversion of benzyl alcohol in mesitylene on hybrid lamellar-bulk MFI (HLBM) zeolite materials containing dual meso-/microporosity showed that the external Bronsted acidity in meso-/microporous MFI zeolites effectively impacts on selectivity of the parallel alkylation and etherification reactions. HLBM zeolites, consisting of crystalline bulk microporous core and lamellar mesoporous shell, not only catalyzed the parallel reactions on the external environments (external surface and mesopore) but also catalyzed the etherification reaction in the internal environment (micropore) as illustrated by the completely suppressed alkylation and retained residual etherification reactions after 2,6-di-tert-butylpyridine (DTBP) poisoning. A systematic study of HLBM zeolites with tunable meso-/microporous domain sizes achieved by a dual template assisted synthesis revealed that parallel alkylation and etherification reactions are tailored by the tunable external surface area and external acidity of the HLBM zeolites. The external alkylation and etherification reaction rates as a function of cumulative DTBP addition suggested the presence of Bronsted acid sites with different strengths on external environments of the HLBM zeolites, which influenced the external etherification reaction, but not as significantly as the alkylation reaction. The evidence shown here for the involvement of external acidity in catalyzing parallel reactions and for the role of external acidity with variable strengths in HLBM zeolite materials extends the scope of observed catalytic behaviors of meso-/microporous zeolite materials beyond those reflecting transport effects and accessibility of acid sites.

Background/Aims: MicroRNAs (miRNAs) have been shown to participate in the development of pancreatic ductal adenocarcinoma (PDAC) by modulating multiple cellular processes. Increased miR-224 expression enhances proliferation and metastasis in human cancers. This study aimed to investigate the role of miR-224 and its underlying mechanism of action in PDAC. Methods: BrdU, MTT, and cell migration assays were performed to determine cell proliferation, viability, and migration, respectively. The binding sites of miR-224 were identified using a luciferase reporter system, whereas protein expression of target genes was determined by immunoblotting and immunofluorescence analyses. A BALB/c nude mouse xenograft model was used to evaluate the role of miR-224 in vivo. Results: We demonstrated that miR-224 expression was enhanced in PDAC cells and tissues, and was related to migration and proliferation. Noticeably, miR-224 overexpression promoted the proliferation, migration, and metastasis of Panc1 cells, while miR-224 inhibition had the reverse effect on PDAC cells. Moreover, we found that thioredoxin-interacting protein (TXNIP) is a target of miR-224. The results also indicated that miR-224 inversely regulated TXNIP by binding directly to its 3′-untranslated region, which resulted in the activation of hypoxia-inducible factor 1α (HIF1α). Further, either TXNIP re-expression or HIF1α depletion abolished the effects of miR-224 on the proliferation and migration of PDAC cells in vitro and in vivo. Regarding the relationship of TXNIP and HIF1α, we found that TXNIP mediated the nuclear export of HIF1α and its degradation by forming a complex with HIF1α. Conclusion: The miR-224-TXNIP-HIF1α axis may be useful in developing novel therapies for PDAC.

A series of experimental results of field-reversed configurations (FRCs) on a KMAX (Keda Mirror with AXisymmetricity) tandem mirror machine are reported. Single-side FRC translation processes with three different gas species were measured by avalanche photodiodes. Consistent with the theoretical prediction, the measured FRC speeds were inversely proportional to the square root of the ion mass. However, the speeds of the hydrogen FRC increased even in a uniform magnetic field region while the speeds of the helium and argon FRCs decreased. Possible mechanisms are discussed. The speed of the second pass due to the reflection of the mirror fields was found to be ~1/3 of the first pass speed. The internal magnetic fields were measured for a colliding-merging argon FRC, and the results show that, even for very slow-moving FRCs, merging can occur.

A dual template synthesis strategy was employed to achieve one-step design of meso- and microporous MFI nanosheet assemblies with tailored morphology, mesoporosity, and catalytic activity. A molecular template (tetrapropylammonium hydroxide, TPAOH) and a polyquaternary ammonium surfactant ([C22H45–N+(CH3)2–C6H12–N+(CH3)2–C6H13]Br2, C22–6–6) were used as cotemplates in the synthesis with a composition of 30Na2O/1Al2O3/100SiO2/10C22–6–6/xTPAOH/4000H2O/18H2SO4. By tuning the concentration of TPAOH (x) from 0 to 20, the morphology of the as-obtained MFI nanosheet assemblies changed from intertwined, to house-of-cards-like, and to dense packing plates. The N2 isotherms showed the hysteresis loop at the range of P/P0 = 0.45–1.0 increases, reaches a maximum, and then decreases with increasing x values, indicating a systematic tailoring of the mesoporosity with TPAOH concentrations. Under strict kinetic control, the rates and apparent activation energies of the ethanol activation in zeolite nanosheet assemblies w...

Dye-sensitized solar cells were fabricated using F-doped TiO2 electrodes. The X-ray diffraction patterns of the F doped TiO2 is almost the same as that of pure TiO2, showing that F has little influence on the formation of anatase titania. The influence of dopant F on band energetics and photoelectrochemical properties of nanostructured TiO2 electrodes was investigated. Compared with pure TiO2 electrodes, the Efb of F-doped TiO2 electrodes shifted little in electrolytes containing LiClO4. The total trap densities were remarkably decreased as TiO2 electrodes were doped with F. Finally the F-doped TiO2 electrodes were sensitized with Ru[L2(NCS)2], L = 2,2′-bipyridine-4,4′-dicarboxylic acid and their photoelectrochemical properties were studied. Experiment results showed that the content of F plays an important role in the photoelectrochemical properties. The highest conversion efficiency of 8.07% was obtained with F-doped TiO2 electrodes containing F0.05 (molar ratio) under irradiation of 100 mW cm−2 white light, about 11.3% higher than that of pure TiO2 electrodes.

Both known and new CC3-based porous organic cages are prepared and exposed to acidic SO2 in vapor and liquid conditions. Distinct differences in the stability of the CC3 cages exist depending on the chirality of the diamine linkers used. The acid catalyzed CC3 degradation mechanism is probed via in situ IR and a degradation pathway is proposed and supported with computational results. CC3 crystals synthesized with racemic mixtures of diaminocyclohexane exhibited enhanced stability compared to CC3-R and CC3-S. Confocal fluorescent microscope images reveal that the stability difference in CC3 species originates from an abundance of mesoporous grain boundaries in CC3-R and CC3-S, allowing facile access of aqueous SO2 throughout the crystal, promoting decomposition. These grain boundaries are absent from CC3 crystals made with racemic linkers.

Molecular modification with polyethylene glycol (PEGylation) is an effective approach to improve protein biostability, in vivo lifetime and therapeutic potency. In the present study, the recombinant human acid fibroblast growth factor (rhaFGF) was site-selectively PEGylated with 20 kDa mPEG-butyraldehyde. Mono-PEGylated rhaFGF was purified to near homogeneity by Sephadex G 25-gel filtration followed by a Heparin Sepharose TM CL-6B affinity chromatography. PEGylated rhaFGF has less effect than the native rhaFGF on the stimulation of 3T3 cell proliferation in vitro; however, its relative thermal stability at normal physiological temperature and structural stability were significantly enhanced, and its half-life time in vivo was significantly extended. Then, the physiological function of PEGylated rhaFGF on diabetic-wound healing was evaluated in type 1 diabetic Sprague Dawley rats. The results showed that, compared with the group of animal treated with native rhaFGF, the group treated with PEGylated rhaFGF exhibited better therapeutic efficacy with shorter healing time, quicker tissue collagen generation, earlier and higher transforming growth factor (TGF)-β expression, and dermal cell proliferation. In addition, in vivo analysis showed that both native and PEGylated rhaFGF were more effective in the wound healing in the diabetic group compared with the nondiabetic one. Taken together, these results suggest that PEGylation of rhaFGF could be a more effective approach to the pharmacological and therapeutic application of native rhaFGF.

A series of polyimides (PIs) with low dielectric constant were synthesized via a polycondensation from two new unsymmetric phthalic-thioether-naphthalic dianhydride isomers which were synthesized from 3- or 4-chlorophthalic anhydride by a four-step procedure. The introduction of the unsymmetric phthalic-thioether-naphthalic dianhydride into polymer backbone is regarded as an effective way to increase the free volume and decrease the intermolecular force and packing ability of the resulting polymers. Thus, the novel PIs exhibit low dielectric constant, low moisture absorption good solubility, high modulus, and high glass transition temperature. The polyimides show good solubility in phenol, dipolar aprotic solvents, and other common organic solvents. In addition, the isomeric effect of 3- and 4-thioether-linked phthalic anhydride on the properties of PIs was discussed.

The petroleum-rich Liaodong Bay basin in Northeast China consists of three depressions (sub-basins) and two uplifts. The Liaozhong depression is the main area of hydrocarbon generation. To date, oil and gas production is mostly from Liaoxi uplift. Early exploration efforts in the deeper portion of the basin indicated that the reservoir quality was poor. However, this study indicates that four distinct zones of secondary porosity and permeability develop in all the depressions and uplifts. The zones of secondary porosity in the depression are relatively deeper than those depths of the same zones in the uplift. Correlations among porosity, permeability, diagenetic stages, evolution of clay minerals, changes in pressure, and thermal maturation indicate the four distinct secondary porosity zones are related to diagenetic evolution, organic matter evolution, clay minerals transformation, overpressure and early hydrocarbon charge. The secondary porosity zones were mainly attributed to the dissolution of the carbonate cement, feldspar and unstable minerals, hydrocarbon generation, and rapid transformation of clay minerals. This result implies that the potential reservoirs with good quality are present in the deeper overpressured portions of the Liaozhong depression.

The kinetics for the complete combustion of methane was studied on a Pd foil in the regions where the oxide and then the metal were the bulk stable phases. The use of a model catalyst allowed the kinetics to be studied at higher temperatures than are possible on supported catalysts since heat and mass transport limitations could be avoided for this nonporous model catalyst. For all reaction conditions, CH4 and O2 reaction orders remained the same at about 0.7 and 0, respectively. With PdO as the stable phase, the water reaction order increased from -1 to 0 and the apparent activation energy (Ea) decreased from 125 to 30 kJ mol(-1) as the reaction temperature increased from 600 to 880 K. We propose that as the temperature is increased water desorbs from the sites responsible for combustion and as a result water inhibition and Ea decrease. To investigate the rate of reaction on Pd versus PdO, the rates were measured around the Pd-PdO transition temperature. The turnover rate decreased from 3.0 s(-1) to 0.3 s(-1) at the transition temperature (907 K with 1.5 Torr O2 and 0.30 Torr CH4) when PdO decomposed to Pd metal, showing that PdO was more active than Pd metal for methane oxidation at this temperature. The reaction orders for Pd metal in the range of 933-1003 K were 0.7, 0, and 0 for methane, water, and O2, respectively, with an apparent activation energy of 125 kJ mol(-1). Thus, the turnover rate and Ea changes suggest that the reaction mechanism for methane oxidation on Pd is different from the one on PdO.

The interaction between silica and palladium following complete oxidation of methane or following reduction in H2 was investigated on a polycrystalline palladium foil and on supported Pd/SiO2 catalysts. During methane oxidation, oxidized silicon covered the palladium oxide surface as observed by TEM on Pd/SiO2 catalysts and by XPS on palladium foil. On the Pd foil, the source of silica was a silicon impurity, common on bulk metal samples. The migration of oxidized silicon onto PdO deactivated the catalysts by blocking the active sites for methane oxidation. Silicon oxide overlayers were also observed covering the Pd surface after reduction of Pd/SiO2 by H2 at 923 K.

The surface area of Pd(111) and Pd(110) single crystals increased after oxidation in O 2 transformed them to PdO. The surface area of the oxide decreased after complete reduction in H 2 . The techniques of STM, TPD, XPS, AES, and LEED were employed to study the Pd(111) and Pd(110) single-crystal surfaces after they were subjected to O 2 oxidation, methane combustion, and H 2 reduction. The surface area of the treated palladium single crystals was measured by 18 O isotope exchange and by direct measurements using the STM image. These two methods showed agreement within 20%. After oxidation in O 2 (100 and 150 Torr) at 600 K, the surface area for both Pd(111) and Pd(110) single crystals increased by a factor of approximately two. The effect was more pronounced on the Pd(111) surface. The oxidized surfaces were covered with 3- to 4-nm semispherical oxide agglomerates that formed a “cauliflower-like” structure 10–20 nm in size. Similar surface structures were observed after exposure of the Pd single crystals to a lean O 2 and CH 4 reaction mixture (O 2 :CH 4 =10:1). Thus, the oxidized single crystal becomes amorphous. Reduction in H 2 decreased the surface area of the preoxidized Pd(111) and Pd(110) crystals. An amorphous metallic surface was produced after H 2 reduction at 373 K, whereas a smooth surface with characteristic single-crystal features was observed after reduction at 673 K. These experiments suggest that oxidizing a Pd metal catalyst or reducing an oxidized Pd catalyst, for example, before palladium metal surface area measurement, will affect the surface area of the sample. It also shows that the increase in surface area on Pd catalysts after oxidation treatment is caused by surface roughening.

Fibroblast growth factor 2 (FGF-2) has a neurotrophic effect on dopaminergic neurons in vitro and in vivo, and exhibits beneficial effects in animal models of neurodegenerative disorders such as Parkinson’s disease (PD). The poor stability and short half-life of FGF-2, however, have hampered its clinical use for neurological diseases. In the present study, we modified native recombinant human FGF-2 (rhFGF-2) by covalently attaching polyethylene glycol (PEG) polymers, named PEGylation, to enhance its neuroprotection efficacy in 6-hydroxydopamine (6-OHDA)-induced model of PD. In vitro, PEG-rhFGF-2 performed better biostability in 6-OHDA-induced PC-12 cells than native rhFGF-2. The in vivo data showed that, compared with native rhFGF-2, PEGylated rhFGF-2 was more efficacious in preventing 6-OHDA-induced lesion upon tyrosine hydroxylase-positive neurons in the substantia nigra (SN), improving the apomorphine-induced rotational behavior and the 6-OHDA-induced decline in tissue concentration of dopamine (DA) and its metabolites. Importantly, our data showed that the superior pharmacological activity of PEGylated rhFGF-2 is probably due to its greater permeability through the blood–brain barrier and better in vivo stability compared to native rhFGF-2. The enhanced stability and bioavailability of PEGylated rhFGF-2 make this molecule a great therapeutic candidate for neurodegenerative diseases such as PD and mood disorders.

This study describes the optimum conditions at the staining time and the signal intensity for using 8-anilino-1-naphthalenesulfonate (ANS) as a fluorescent probe to detect proteins in SDS-PAGE. Using the optimized protocol, protein can be easily detected by short time fixing (20 min) and washing (2 × 5 min), followed by 10 min of staining. As low as 1-2 ng of the protein band can be detected, approximately thirty-fold higher than that of the original protocol. Furthermore, the compatibility of the staining method with MS was also explored by comparing the peptide mass fingerprinting results data of serial dilutions of BSA and ovalbumin stained by ANS with SYPRO Ruby.

Keratinocyte growth factor 1 (KGF-1) has proven useful in the treatment of pathologies associated with dermal adnexae, liver, lung, and the gastrointestinal tract diseases. However, poor stability and short plasma half-life of the protein have restricted its therapeutic applications. While it is possible to improve the stability and extend the circulating half-life of recombinant human KGF-1 (rhKGF-1) using solution-phase PEGylation, such preparations have heterogeneous structures and often low specific activities due to multiple and/or uncontrolled PEGylation. In the present study, a novel solid-phase PEGylation strategy was employed to produce homogenous mono-PEGylated rhKGF-1. RhKGF-1 protein was immobilized on a Heparin-Sepharose column and then a site-selective PEGylation reaction was carried out by a reductive alkylation at the N-terminal amino acid of the protein. The mono-PEGylated rhKGF-1, which accounted for over 40% of the total rhKGF-1 used in the PEGylation reaction, was purified to homogeneity by SP Sepharose ion-exchange chromatography. Our biophysical and biochemical studies demonstrated that the solid-phase PEGylation significantly enhanced the in vitro and in vivo biostability without affecting the over all structure of the protein. Furthermore, pharmacokinetic analysis showed that modified rhKGF-1 had considerably longer plasma half-life than its intact counterpart. Our cell-based analysis showed that, similar to rhKGF-1, PEGylated rhKGF-1 induced proliferation in NIH 3T3 cells through the activation of MAPK/Erk pathway. Notably, PEGylated rhKGF-1 exhibited a greater hepatoprotection against CCl(4)-induced injury in rats compared to rhKGF-1.

The aim of the present study was to investigate the apoptosis of human ovarian cancer cell lines, A2780 and CP70, induced by a novel curcumin analogue, B19. The proliferation of cells was detected with methyl thiazolyl tetrazolium (MTT) assay and apoptosis was examined by flow cytometry. Reactive oxygen species (ROS) were assessed by the fluorescent indicator DCF-DA. The protein expression of the endoplasmic reticulum (ER) stress pathways, GRP78, XBP-1, ATF-4 and CHOP, was examined with Western blotting. A growth inhibitory effect was observed after treatment with B19 in a dose-dependent manner and with more potential than curcumin. At 20 µM, B19 induced significant apoptosis in CP70 cells. Furthermore, B19 induced the ER stress response, while curcumin had no effect on ER stress. These results suggest that B19 has more effective antitumor properties than curcumin, and is associated with the activation of ER stress and ROS in ovarian cancer cells.

There is increasing evidence indicating that inflammatory processes are involved in the development and progression of diabetic complications. However, effective anti-inflammatory treatments for patients who have diabetic complications have yet been practically identified. Curcumin is a main component of Curcuma longa with numerous pharmacological activities. Previously, we synthesized a novel curcumin analogue (B06) that exhibited an improved pharmacokinetic and enhanced anti-inflammatory activity compared to curcumin. The present study aimed to test the hypothesis that B06 may reduce high-glucose-induced inflammation and inflammation-mediated diabetic complications. In vitro, pretreatment with B06 at a concentration of 5 μM significantly reduced the high-glucose-induced overexpression of inflammatory cytokines in macrophages. This anti-inflammatory activity of B06 is associated with its inhibition of c-Jun N-terminal kinase/nuclear factor κB activation. In vivo, despite that B06 administration at 0.2 mg · kg(-1) · d(-1) for 6 weeks did not affect the blood glucose profile of diabetic rats, the B06-treated animals displayed significant decreases in inflammatory mediators in the serum, kidney, and heart and renal macrophage infiltration. This was accompanied with an attenuation of diabetes-induced structural and functional abnormalities in the kidney and heart. Taken together, these data suggest that the novel derivative B06 might be a potential therapeutic agent for diabetic complications via an anti-inflammatory mechanism and support the potential application in diabetic complication therapy via anti-inflammatory strategy.

As one of fibroblast growth factor (FGF) family members, FGF21 has been extensively investigated for its potential as a drug candidate to combat metabolic diseases. In the present study, recombinant human FGF21 (rhFGF21) was modified with polyethylene glycol (PEGylation) in order to increase its in vivo biostabilities and therapeutic potency. At N-terminal residue rhFGF21 was site-selectively PEGylated with mPEG20 kDa-butyraldehyde. The PEGylated rhFGF21 was purified to near homogeneity by Q Sepharose anion-exchange chromatography. The general structural and biochemical features as well as anti-diabetic effects of PEGylated rhFGF21 in a type 2 diabetic rat model were evaluated. By N-terminal sequencing and MALDI-TOF mass spectrometry, we confirmed that PEG molecule was conjugated only to the N-terminus of rhFGF21. The mono-PEGylated rhFGF21 retained the secondary structure, consistent with the native rhFGF21, but its biostabilities, including the resistance to physiological temperature and trypsinization, were significantly enhanced. The in vivo immunogenicity of PEGylated rhFGF21 was significantly decreased, and in vivo half-life time was significantly elongated. Compared to the native form, the PEGylated rhFGF21 had a similar capacity of stimulating glucose uptake in 3T3-L1 cells in vitro, but afforded a significantly long effect on reducing blood glucose and triglyceride levels in the type 2 diabetic animals. These results suggest that the PEGylated rhFGF21 is a better and more effective anti-diabetic drug candidate than the native rhFGF21 currently available. Therefore, the PEGylated rhFGF21 may be potentially applied in clinics to improve the metabolic syndrome for type 2 diabetic patients.

A zeolite@metal–organic framework (ZSM-5@UiO-66) core–shell composite has been synthesized for the first time by solvothermal growth of UiO-66 on the surface of ZSM-5 particles. The acidity from ZSM-5 and the basicity from the amine groups in UiO-66 obtained by post-synthetic modification of the metal clusters, endow a bifunctionality on ZSM-5@UiO-66 for cascade reactions.

Determination of the postmortem interval (PMI) is crucial for investigating homicide. However, there are currently only limited methods available. Especially, once the PMI exceeds the duration of pre-adult development of the flies with the adult emergence, its determination is very approximate. Herein, we report the regular changes in hydrocarbon composition during the weathering process of the puparia in the field in Chrysomya megacephala (Fabricius) (Diptera: Calliphoridae), one of the common species of necrophagous flies. Correlation analysis showed that the relative abundance of nearly all of the branched alkanes and alkenes decreased significantly with the weathering time. Especially, for 9 of the peaks, over 88% of the variance in their abundance was explained by weathering time. Further analysis indicated that the regular changes caused mainly by the different weathering rates of various hydrocarbons. Additionally, the weathering rates were found to depend on the chemical structure and molecular weight of the hydrocarbons. These results indicate strongly that hydrocarbon analysis is a powerful tool for determining the weathering time of the necrophagous fly puparia, and is expected to markedly improve the determination of the late PMI.